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How to speak to Human Singtel Customer Officer

Just to reblog this post on how to contact a human Singtel customer service operator. Do share it with your friends/relatives as it can be **extremely** difficult to contact Singtel during times of need.

Singapore Maths Tuition

If you try calling the Singtel hotline 1688, you will spend most of your time to navigate the maze of options trying to speak to a human Singtel Customer Officer. I have not managed to successfully find the option to speak to a human Singtel Chat Agent through the hotline, if you know the method please comment below!

Also, do not bother speaking to “Shirley” on the Contact Us page (https://www.singtel.com/contact-us). It is quite clear Shirley is not a human, but just a bot.

The Trick to Chat with a Human Singtel Customer Officer

  1. Go to the Contact Us page.
  2. Click on Ask Shirley
  3. Type “can i chat with customer service officer”.
  4. Type in the category of your question, e.g. “billing”, “voucher”, etc.
  5. Whatever Shirley says, just click “Submit Enquiry”
  6. Bingo! You are now connected to a Human Chat Agent!

From trial and error, this is the easiest…

View original post 52 more words

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“In my daughter’s school, no one scored A1 for Higher Chinese for the recent GCE O Levels”

O Level Higher Chinese Distinction Rate

Quite surprising to see news on Kiasuparents that the distinction rate for ‘O’ Levels HCL is so low.

Case study 1)

In the below case study, zero students scored A1 for Higher Chinese in the recent O Levels. This is very surprising since even in neighborhood schools, we would expect there to be at least a few students strong in Chinese. For example for Mathematics, even in neighborhood schools there is guaranteed to be at least a few students scoring A1.

In my DD’s (dear daughter) school, no one scored A1 for Higher Chinese for the recent GCE O Levels.

This is very surprising becos there are students who are very academically inclined and some have shown consistent strength in the subject over the 4 years in secondary school.

I wonder how other secondary schools perform in this subject. Or did MOE raised the standard or the school is just unlucky where their students exam papers were marked by an unusually strict examiner/marker?

Source: https://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=40&t=67330&start=2750

Case Study 2)

The below case study is also very surprising since SAP schools are known to have a heavy emphasis on Chinese language and culture, usually leading to excellence in the Chinese subject. Examples of top SAP schools include Dunman High, Catholic High, Chung Cheng High School (Main), etc.

The distinction (rate) for HCL in my DS school is 29.6%. Considering that he is from a SAP school with strong Chinese culture.. this is quite low.. but to be fair.. with 8-9 subjects to manage and knowing that C6 will get you the 2 bonus points.. how many kids will aim for A1? My DS got C6 and he is happy that he got his 2 bonus points..

Source: https://www.kiasuparents.com/kiasu/forum/viewtopic.php?f=40&t=67330&start=2750


Do check out our blog post on O Level Bell Curve.

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Boeing mocked Lion Air calls for more 737 Max training before crash

Source: Straits Times

JAKARTA (BLOOMBERG) – Indonesia’s Lion Air considered putting its pilots through simulator training before flying the Boeing 737 Max but abandoned the idea after the planemaker convinced them in 2017 it was unnecessary, according to people familiar with the matter and internal company communications.

The next year, 189 people died when a Lion Air 737 Max plunged into the Java Sea, a disaster blamed in part on inadequate training and the crew’s unfamiliarity with a new flight-control feature on the Max that malfunctioned.

Read more at: https://www.straitstimes.com/world/united-states/boeing-mocked-lion-air-calls-for-more-737-max-training-before-crash

Quite unbelievable that such lack of regard for safety was demonstrated by Boeing. Note that the above news is taken from a major newspaper in Singapore, the Straits Times.

Another news by Bloomberg: Boeing’s 737 Max Software Outsourced to $9 -an-Hour Engineers.

The real reason Boeing 737 Max crashed twice is a software problem!

According to the video below, the real reason why the Boeing 737 Max crashed twice is none other than a software problem! (The software called MCAS keeps pushing the nose of the airplane downwards.)

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Paul Krugman Masterclass Review

URL: Paul Krugman Teaches Economics and Society

Paul Robin Krugman is an American economist who is the Distinguished Professor of Economics at the Graduate Center of the City University of New York, and a columnist for The New York Times. His notable awards include the Nobel Prize for Economics!

Students studying economics in high school or university are highly recommended to watch his Masterclass lessons (link to Masterclass website). It is always good to listen to insights from masters who have experienced economics at the highest level.

Prof. Krugman is also the author of a university level textbook titled Economics (co-written with Robin Wells):

He also writes several popular economic books for laymen, such as The Return of Depression Economics and the Crisis of 2008, where he predicts that the world’s economy is sliding into a deep recession (recall he is a Nobel Prize winner in Economics, not just any “bogus” author!). He also gives tips on how to avoid catastrophe in this case.

A detailed video review of Paul Krugman’s Masterclass is available below:

Link to his masterclass here: Masterclass Official Website (Krugman Economics)

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Shopee Promo Code

Herewith is a code for Shopee SG offer:

Promo Code: IACNYNEW
$8 off with min. spend of $16
Valid from 2 Jan 2020, 00:00 to 31 Jan 2020, 23:59

Click on this link to enter the official Shopee website: Shopee.sg

(Please use the link above directly, thanks!)

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O Level Bell Curve

Is there “bell curve” for O Levels / A Levels or not?

The answer is “it depends on how you define bell curve”! Technically, no, bell curve is not used but something very similar called “grade boundaries” is being used to determine who gets A1 or A.

Read the below blog post for more information!

Singapore Maths Tuition

Source: https://www.reddit.com/r/singapore/comments/73cmgi/o_level_bellcurve/

It is well known that the “bell curve” is applied to the O Levels result. The most notorious example is E Maths, where 90+ or high 80s is required for the top grade of A1. The traditional mark of 75 is only enough for B3/B4 in the actual O levels.

Update: According to official sources, “grade boundaries” instead of bell curve is being applied to O Levels / A Levels. Technically, there is a subtle difference between the two since the bell curve refers to the normal distribution in statistics. Hence, technically, “bell curve” is not applied to O levels. However, for laymen, “grade boundaries” and “bell curve” are essentially the same thing, meaning that the percentage of A1s or As is being externally controlled by the examiners in the form of “grade boundaries”. It is definitely not the case that 75 marks is sufficient for A1…

View original post 329 more words

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Free Exam Papers Latest Update

We have revamped our popular page on Free Exam Papers / Free Test Papers, fixing broken links and ensuring that the links to the PDF exam papers are updated.

Basically, the page above will help you to save money in obtaining free exam papers at virtually no cost. The only cost is paper and ink to print out the exam paper.

The Free Exam Papers listed covers majority of levels (Primary, Secondary, JC) and topics (Languages, Sciences, Maths, Humanities).

It is highly recommended to download the free exam papers as soon as possible, in advance, since from experience such sites can go down at any moment.

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Biggest Fairprice store in Singapore

Biggest NTUC Fairprice in Singapore

My previous post on Biggest Sheng Siong Outlet became quite popular. Hence, I decide to write a related post on the largest Fairprice supermarket (also known as NTUC supermarket) in Singapore.

No. 1 Largest Fairprice in Singapore: VivoCity

It is quite universally agreed that the largest Fairprice store in Singapore currently is the one at VivoCity, replacing the Giant store that was previously there. It is reported in the news that the Fairprice Xtra hypermarket is the largest in Singapore currently as of late 2019. Source of news is at: Largest FairPrice Xtra hypermarket opens at VivoCity.

I have been to the Fairprice in VivoCity, and it is indeed big. However, the layout of the store is quite “open” and “sparse” in the sense that there are many open spaces and the food item shelves are spaced wide apart. Hence, in terms of dense stocking and amount of items, it may not be as “big” as the next followup, the second largest Fairprice in Singapore.

No. 2 Largest Fairprice in Singapore: Ang Mo Kio Hub

With a bit of logical deduction, we can deduce that the second largest Fairprice in Singapore is the one at Ang Mo Kio Hub, also known as AMK Hub.

A few blog posts online still list AMK Hub Fairprice as the largest Fairprice (before the opening of the Vivocity Fairprice). For instance:

Fairprice Xtra has its biggest outlet located in Ang Mo Kio Hub. The total area of the hypermarket is 7150 square metres. In comparison, a full sized standard Olympic swimming pool is 1250 square metres. That is almost 6 full sized swimming pools.

Source: https://goodyfeed.com/4-things-you-probably-didnt-know-about-fairprice-xtra/

Hence, if AMK Hub Fairprice Xtra used to be the largest Fairprice, it makes perfect sense that it is now the second largest Fairprice after the one at VivoCity.

Largest Fairprice in the West

Jurong Point has a very big Fairprice that is open 24 hours. Its address is Address: 63 Jurong West Central 3, #03 – 01, Singapore 648331.

It may be unbelievable, but Jurong Point has another Fairprice in the same building, located at 1 Jurong West Central 2, #B1 – 09, Singapore 648886. Hence, it is quite guaranteed that whatever you need can be found in Jurong Point. If you combine the two Fairprice together, it is quite certain that the largest Fairprice in the West is at Jurong Point (both Fairprice outlets lumped together as one).

Another large Fairprice is found in JEM (Jurong East). Its address is at Jem: 50 Jurong Gateway Road #B1-21/22 & #B3-01, 608549. The location is better than the Jurong Point Fairprice for most Singaporeans, unless you are living in the extreme West (e.g. Boon Lay region). The large Fairprice in JEM has live seafood, including Boston lobsters, certain fish like tilapia, etc.


If you know other large Fairprice supermarkets, do comment below! In particular, it may be of great interest which is the largest Fairprice Finest, or normal Fairprice supermarket.

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Best Pattern Recognition and Machine Learning Book (Bishop)


Pattern Recognition and Machine Learning (Information Science and Statistics)

The above book by Christopher M. Bishop is widely regarded as one of the most comprehensive books on Machine Learning. At over 700 pages, it has coverage of most machine learning and pattern recognition topics.

It is considered very rigorous for a machine learning (data science) book, but yet has a lighter touch than a pure mathematics or theoretical computer science book. Hence, it is perfect as a reference book or even textbook for students self learning the subject from the ground up (i.e. students who want to understand instead of just blindly apply algorithms).

A brief overview of the contents covered (taken from the contents page of the book):

  1. Introduction

  2. Probability Distributions

  3. Linear Models for Regression

  4. Linear Models for Classification

  5. Neural Networks

  6. Kernel Methods

  7. Sparse Kernel Machines

  8. Graphical Models

  9. Mixture Models and EM

  10. Approximate Inference

  11. Sampling Methods

  12. Continuous Latent Variables

  13. Sequential Data

  14. Combining Models

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Sum of two metrics is a metric

It is quite straightforward to prove or verify that the sum of two metrics (distance functions) is still a metric.

Suppose d_1(x,y) and d_2(x,y) are metrics. Define d(x,y)=d_1(x,y)+d_2(x,y).

Positive-definite

d(x,y)\geq 0+0=0.

d(x,y)=0 \iff d_1(x,y)=d_2(x,y)=0 \iff x=y.

Symmetry

d(x,y)=d_1(y,x)+d_2(y,x)=d(y,x).

Triangle Inequality

\begin{aligned}    d(x,y) &\leq d_1(x,z)+d_1(z,y)+d_2(x,z)+d_2(z,y)\\    &=[d_1(x,z)+d_2(x,z)]+[d_1(z,y)+d_2(z,y)]\\    &=d(x,z)+d(z,y)    \end{aligned}

Note that it follows by induction that the sum of any finite number of metrics (e.g. three, four or five metrics) is still a metric.

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Yusheng Promotion: 8 pax at only S$18.90 (A-One Claypot House)

[S$18.90](▼35%)🎁[A-One Claypot House]Prosperity Abalone Yu Sheng Serving up to 8 pax.(U.P $28.90).

WWW.QOO10.SG

This is quite a good deal (top seller on Qoo10). A-One is a well-known Chinese restaurant famous for their claypot dishes. The list of ingredients is quite extensive as well (includes abalone).

Do read the 1859 mostly positive reviews before you make your final decision!

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Crying Koala Saved by Woman (Australian bushfire)

This looks like scene from hell! Poor koala is burnt by the bushfire. I didn’t know koala can make crying sounds.

To donate, please go to the official WWF website:

https://www.wwf.org.au/get-involved/bushfire-emergency#/

It is estimated by experts that koalas will go extinct by 2050 (or earlier)!

#bushfire

What happened to the Koala rescued from the bush fire?

Very unfortunately, the Koala rescued (named Lewis), has passed away on November 26 due to euthanasia for the severe burn injuries. Rest in peace.

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Python save csv to folder

In Python (pandas), saving a .csv file to a particular folder is not that hard, but then it may be confusing to beginners.

The packages we need to import are:

import pandas as pd
import os.path

Say, your folder name is called “myfolder”, and the dataframe you have is called “df”. To save it insider “myfolder” as “yourfilename.csv”, the following code does the job:

df.to_csv(os.path.join('myfolder','yourfilename.csv'))

The reason this may be difficult for beginners is that beginners may not know of the existence of the os.path.join method, which is the recommended method for joining one or more path components.

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IP Math Syllabus (Integrated Programme Mathematics)

Students and parents new to IP (Integrated Programme) may be confused on what is the Mathematics syllabus of IP Math. Indeed, it is very confusing as every school has its own syllabus. In general, the syllabus as a whole is not that different from ‘O’ level Mathematics, but the order in which the school teaches is unique to each school.

In general, the topics can be divided as follows, following the famous assessment book “Mathematics (Integrated Programme)” by Wong-Ng Siew Hiong who is a teacher at RI. This is one of the very few IP Math books available in local bookstores.

Secondary 3 IP Math Syllabus

  1. Geometrical Properties of Circles
  2. Solutions to Quadratic Equations
  3. Matrices & Simultaneous Equations
  4. Quadratic Functions, Inequalities & Roots of Equations
  5. Sets
  6. Relations & Functions
  7. Indices & Surds
  8. Exponential, Logarithmic & Modulus Functions
  9. Polynomials & Partial Fractions
  10. Graphical Solutions & Transformations
  11. Circular Measure
  12. Plane Geometry
  13. Coordinate Geometry & Equations of Circles
  14. Linear Law
  15. Trigonometry
  16. Further Trigonometry

Secondary 4 IP Math Syllabus

  1. Binomial Theorem
  2. Probability
  3. Statistics
  4. Vectors
  5. Differentiation Techniques
  6. Differentiation and its Applications
  7. Integrated Techniques
  8. Applications of Integration
  9. Integration Applications — Area and Kinematics
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Cheap alternative to Dyson Vacuum (Xiaomi DREAME V9 Pro)

Though Singapore is a relatively rich country, many people still find Dyson Vacuum Cleaners unaffordable since it is well over a thousand dollars.

Fortunately, there is a cheap and good alternative to Dyson Vacuum Cleaners (with many positive reviews): Xiaomi DREAME V9 Pro. (Some people actually claim that it is more powerful than Dyson vacuums! See the video at the end of this post.)

For example, an actual review by a Singaporean states:

My friend got it for her 3-room flat and she said this vacuum cleaner not bad. She gave me the courage to purchase it as I have been considering for a long time. After I received it, a test-out session became vacuum the whole house (it still has 1 bar battery when it arrived). The maneuvering is smooth, which let me vacuum the whole 4-rm flat effortlessly. I am a lady, so it should be fine for most people. Thumbs up!

Source: https://qoo.tn/BaT8BW/Q100000595

[S$219.00](▼46%)Xiaomi DREAME V9 Pro Cordless Vacuum Cleaner | 20 000 Pa Suction Power | Long Battery Life

WWW.QOO10.SG


It is almost compulsory for every household in Singapore to have a vacuum cleaner, since our hot and humid climate makes dust mites grow and reproduce very fast if we don’t vacuum away the dust. In addition, many young children tend to have some form of childhood asthma in Singapore.

Do read all the reviews of the Xiaomi cordless vacuum cleaner before making your decision!

For international buyers, you may find the Xiaomi Dreame V9 on Amazon as well:

Dreame V9 Pro Cordless Vacuum Hyper Clean Cordless Cleaner, Super for All Carpet and Hardwood Floor Stick Vacuum with Powerful Digital Motor, Handheld with Rechargeable Lithium Ion Battery

Below is the YouTube reviewer who claims that the Xiaomi Dreame V9 is more powerful than Dyson in terms of suction:

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Ohm Electricity Renewal

Just renewed my subscription to Ohm Energy today.

Use the below Ohm Promo code if you decide to switch to Ohm: *Ohm Promo Code: OHMREF25CC5A

Here are some advantages of choosing Ohm:

  • Switching to Ohm will not cause any disruption to your electricity supply. Your electricity comes from the national power grid which will continue to be operated and delivered by SP Group.
  • You will receive your electricity at your premises from Ohm during the Supply Term of your Agreement with us.
  • Your security deposit is collected and retained by SP Group on our behalf. If you were purchasing from a retailer other than SP Group or a retailer that is using SP Group for billing services before switching to Ohm, the initial security deposit will be equivalent to 65% of the security deposit as determined and published by SP Group for its residential premises utilities account. If you were purchasing electricity from SP Group at the regulated tariff or from a retailer that is using SP Group for billing services before switching to Ohm, SP Group will allocate 65% of the security deposit that you have set aside with them as our Ohm security deposit. You don’t need to do anything.
  • SP Group acts as our billing agent. This means that your Ohm electricity charges will still appear on the same bundled utilities bill that you get from SP Group. SP Group will also be collecting your monthly payments and operating our Customer Care.
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Tetra Vacation Food Review (Holiday Fish Food)

Just wanted to give a positive review for the Tetra Vacation “Slow Release Feeder” Holiday fish food, which feeds up to 14 days.

I went for a vacation for around 12 days, and came back to zero fish/snail/shrimp deaths, and perfectly healthy fish!

The fish I had were:

  • 5 neon tetras
  • 2 lambchop rasboras
  • 2 Rili Shrimp
  • 1 Amano Shrimp
  • 2 Horned Nerite Snails

All were surviving well after the vacation. It was quite clear that the shrimp and snails were able to eat the food as well (I saw them eating the food, as well as their poop on the feeding dish).

Tips for using the Tetra Vacation fish food

  1. I think the key is not to put too much. If you only have a few tetras, estimated of 1/8 of the entire block will be more than enough. The entire block is overkill and may increase the chances of polluting the water.
  2. Buy a plastic dish (food safe), such as Melamine Plastic Sauce Dishes, 1 oz, 2-3/4″, White (Set of 15) to hold the food and prevent contact with substrate. I found that this reduces the chance of the Tetra holiday food turning mouldy. This is a cheap but still viable alternative to the proper method which is to use a Shrimp feeding dish such as Senzeal 2X Aquarium Glass Shrimp Feeding Dish Bowls Reptiles Water Food Dish Feeder Bowl Round.

Tetra Vacation food packaging looks like the ones below:


Tetra Vacation Tropical Slow Release Feeder, 2.12-Ounce


Tetravacation 14-Day Feeder For Tropical Fish. 4 Pack (4.24 Oz Total).

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Useful Apps Homeschooling Parents Can Use to Help Their Children Learn

Useful Apps Homeschooling Parents Can Use to Help Their Children Learn

There are many educational apps that are available to help students with various activities, but very few of them were specific to homeschooling parents. As I was researching apps that can make the lives of homeschooling parents easier, I came across this list of apps that I thought were very useful.

List of Useful Apps for Children Homeschooling

Each of them serves a different purpose and let’s broadly explore how they can be useful for homeschooled children.

Explore the free resources available to homeschool children

Given the rise in popularity in digital media and the Internet, many families are now resorting to free resources that are available online. Without the need to go to a formal school, parents now opt to take advantage of the online courses for kids that are freely available. There are several benefits to homeschooling children of different ages, especially in terms of cost.

As a parent, if you are not working full time and decide to do it on your own, you could homeschool for free using various resources available at your disposal.

Resources to help homeschooling parents working full time

Homeschooling as a working parent can be quite a challenge especially if you are employed full time. Chances are that you may not find enough time to homeschool your children. This would be more difficult if both parents are working full time. Fortunately, there are many homeschooling programs carried out by professionals that help working parents to homeschool their kids.

Depending on the field that your child chooses to pursue, you can hire a specialist in a particular area and hire their services for a fee. Additionally, you could consider subscribing to online courses that have a set of scheduled lessons that your kids can work their way through. For instance, Udemy and Coursera have a ton of free and paid courses from well-recognized universities that you could make use of. However, it is important that you maintain a strict schedule to ensure they are on track.

Use apps that specifically help students achieve great results

If you have a smart device such as a phone or a tablet, you can make good use of it if you have the relevant apps installed. There are homeschooling apps that are dedicated to helping your children learn more interactively at home.

For example, Khan Academy provides plenty of material on various subjects which can be extremely helpful for children should you decide to make them learn on their own. However, as a parent, you will need to make sure that you organize the schedule and checklists constantly which can be quite daunting tasks. Apps such as Wunderlist can be very useful as it helps you manage a to-do list very easily.

Additionally, you will also need to ensure you have controls on balancing your children’s time on and off the school. Apps such as FamilyTime allow you to set limits on screen time, including bedtime restrictions, and it even lets you lock your kids’ phones when they are supposed to be doing homework.

If you also need a working calendar that helps you organize various events and activities that your children need to take as part of the homeschooling program, you can use Cozi that syncs the calendars of all the members in the family so everyone is updated on each other’s schedule. This way, it can be easier for each member to share the responsibilities easily. It’s indeed a helpful homeschooling tool that can help you and your family be more organized.

Conclusion

With many online resources and tools available, homeschooling your kids doesn’t have to be a difficult task as it used to be. If you have them in place with the necessary arrangements, you can easily breeze helping your child homeschool.

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Ohm Promo Code YouTube video

Ohm Promo Code: OHMREF25CC5A

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Ohm Energy Review

For those who are still hesitating on whether to switch to Ohm, I have collated all our previous blog posts on why you should choose Ohm, also known as Ohm Energy:

Website: https://ohm.sg/price-plans-select

*Ohm Promo Code: OHMREF25CC5A

  1. Ohm vs Geneco vs Tuas Power vs Keppel
  2. Fixed Ohm vs Ohm Discount
  3. Ohm Electricity Review
  4. Ohm $20 Promo Code: OHMREF25CC5A

The sooner you switch to Ohm, the more money you will save. Do help your older relatives (who may not be computer literate) switch to Ohm as soon as possible. There is literally zero benefit in staying with SP services as it is definitely more expensive.

A typical family would see about 20%-30% monthly savings in electricity bill (see this news article).

*Ohm Promo Code: OHMREF25CC5A

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Ohm vs Geneco vs Tuas Power vs Keppel

*Ohm Promo Code: OHMREF25CC5A

Firstly, just a disclosure that I am a happy customer of Ohm since 1 Nov 2018 (see my Ohm review blog post). Everything, from payment to electricity supply, is virtually perfect and hassle-free. It is very easy and quick to sign up online.

The purpose of this blogpost is to compare Ohm vs the other major electricity providers. All conclusions will be supported by factual numbers from the respective official websites, as far as possible. The final decision will be entirely up to you, the reader. If you decide to choose Ohm, do use the below discount coupon code to enjoy $20 savings:

*Ohm Promo Code: OHMREF25CC5A

Note that there are many price plans (fixed, discount off tariff, etc.) hence we will only be comparing discount plans for convenience (very popular and cost-effective plan for most users). Discount plans essentially guarantee that you will be paying less than if you stayed with SP Services. For Fixed Plans there is a small but nonzero risk that the SP Services Tariff may drop so much that your Fixed Plan is more expensive than the SP Service Tariff.

One important thing to note is that:

Ohm absorbs the transmission loss. (Basically electrical energy is lost as heat while traveling through the cable, Ohm absorbs this and charges consumer based on metered usage. This is worth approximately 3.4% savings.)

Source: https://mathtuition88.com/2018/11/01/ohm-20-promo-code-ohmref25cc5a/ which is in turn taken from https://www.ohm.sg/news.

Ohm vs Geneco

For many reasons, Geneco is the number one comparison made to Ohm, due to several similarities (they both have a strong online presence and referral program).

Ohm has an upper hand in the discount-off tariff rate, since the Ohm Discount is 25% off SP (Singapore Power) tariff, while Geneco’s discount is 22% off tariff.

(By the way, we have a detailed analysis of why Ohm Discount is currently better than Fixed Ohm: Fixed Ohm vs Ohm Discount.)

To top it off, there is additional 1.5% discount when you renew your Ohm discount plan:

12-month Ohm Discount – Additional 1.5% discount on prevailing 12-month Ohm Discount rate (at point of renewal) throughout Supply Term

Source: https://ohm.sg/promotions

Ohm Discount off tariff is 25%.

Geneco discount rate is 22%.

Conclusion: Ohm (King of “Discount-off Tariff” Plans) wins!

Ohm vs Tuas Power

Tuas Power, similar to Geneco, has a 22% off tariff plan. To their credit, Tuas does have a 1% cashback plan with POSB Everyday Card.

Simple math will tell you that Discount Ohm (25% + 1.5% upon renewal) is still better in this case.

22% Discount off Tariff for Tuas Power.

Conclusion: Ohm (King of “Discount-off Tariff” Plans) wins!

Ohm vs Keppel

Keppel electric also has 22% off tariff plan.

Keppel Electric 22% off tariff plan.

Conclusion: Ohm (King of “Discount-off Tariff” Plans) wins!

As you can see from the screenshots above (taken from the actual official websites), the Discount Ohm plan is virtually unbeatable in the Singapore market in the “Discount-off Tariff” category.

To be fair, we need to state that the Fixed Ohm plan may not be the very best in Singapore, but is still very competitive nonetheless (just a few cents off the cheapest in Singapore).

Do share this with your relatives/friends who are about to switch electricity providers! It just takes 10 minutes of your time, but can save potentially thousands of dollars.

Ohm website: https://www.ohm.sg/price-plans-select

*Ohm Promo Code: OHMREF25CC5A

Ohm vs Other Electricity Providers

As of 3 Oct 2019, there are 12 electricity retailers (https://blog.moneysmart.sg/budgeting/open-electricity-market-singapore/):

  1. Best Electricity Supply Pte Ltd
  2. Diamond Energy Merchants Pte Ltd
  3. Geneco (by Seraya Energy Pte Ltd)
  4. iSwitch Pte Ltd
  5. Keppel Electric Pte Ltd
  6. Ohm Energy Pte Ltd
  7. PacificLight Energy Pte Ltd
  8. Sembcorp Power Pte Ltd
  9. Senoko Energy Supply Pte Ltd
  10. Sunseap Energy Pte Ltd
  11. Tuas Power Supply Pte Ltd
  12. Union Power Pte Ltd

Basically, you will need to check up one by one, to see their updated plans and how they compare to Ohm. Remember to check for the fine print and see if they absorb transmission loss or not (that alone is worth 3.4% savings, which Ohm provides). Ohm is very transparent in their plans, which is another plus for Ohm — they do not hide important details in “fine print”.

Some plans are very fanciful (e.g. free tablet computer, iPad, etc) but do not provide best value for money. It is much better to stick with a plain plan that provides maximum savings (e.g. Discount Ohm), and use the savings to buy the free gift/iPad yourself if you really want it.

Basically, anyone who really sits down and do the number-crunching can tell that Ohm (in particular Discount Ohm) is a very good choice and one of the best in Singapore. How Ohm achieves this is they spend low on advertising (you will never see a Ohm promoter on the streets asking you to sign up). With those savings in advertising costs, they pass it on to the consumer (you) in terms of lower prices.


Ohm website: https://www.ohm.sg/price-plans-select

*Ohm Promo Code: OHMREF25CC5A

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Ulgrim guide

Ulgrim is one of the lesser used legends in Brawlhalla, but I think he is probably one of the easiest legends for beginners (and also viable at high levels).

Reason being his two weapons lance and axe are very easy to land hits. Lance is great at horizontal approaches, many people at rank gold and below do not know how to properly counter lance. Axe is shorter range than lance (but still has decent range) and has very wide hit boxes. Both lance and axe are not combo-heavy (essentially both weapons only have a couple of combos) so there is no need for much “practicing combos”.

There is some criticism about his lance sigs (only the neutral sig is good). However, his axe sigs are very good (neutral sig and down sig are excellent, side sig is ok).

Both in 1v1 and 2v2, Ulgrim is very playable for beginners. He is above average (6 points) in all stats except dexterity.

Basically, in the “neutral game” you can use lance to rack up damage, and then switch to the axe for the kill. For weapons that lance is very disadvantaged against (e.g. blasters or axe), use axe instead all the way. See this Lance Matchup Tier List for more info. For low levels (gold and below), as mentioned above, virtually no one knows how to counter lance, so you can still use lance very effectively against any weapon.

Beginner Ulgrim Guide

This method can work up to gold.

Lance: Just try to keep doing side air/down air. It is very easy to for you to hit, and very hard for your opponent to counter.

Axe: Try doing Nlight or Slight->Dlight. If your opponent is very jumpy, try to catch them with Dlight.

For a detailed Ulgrim guide, do check out the video below:

One of the top YouTubers, Cosolix, has also recently switched to Ulgrim as his main.

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SimplyGo App Review and Suggestion

SimplyGo is a wonderful app that allows you to use your Mastercard/ Visa credit cards as an “Ez-link” for public transport.

Currently, certain credit cards do have “cashback” for SimplyGo, in particular:

Contactless spending cashback cards: DBS Live Fresh, DBS Visa Debit Card, StanChart Spree Card. These are cards that give you bonus cashback on contactless payment, i.e. Visa PayWave, Apple Pay etc. Currently, SimplyGo transactions are counted as contactless payments too.

Source: https://blog.moneysmart.sg/transportation/transitlink-simplygo-abt/

SimplyGo Monthly Total Expenditure

Currently, possibly the only drawback of SimplyGo is that the fees reporting (both in your credit card statement and also in the app) is quite messy. Basically, it is not totaled up in a nice manner.

MoneySmart also has a similar comment:

Yep, it’s a complete mess. The transactions seem to go through at random intervals instead of something sensible, like 1-week intervals, so it’s hard for me to tell if there are any potentially fraudulent charges or any other errors.

Source: MoneySmart

For those who need to total up your monthly transport expenditure (for your own tracking), you will need to do so rather manually by calculator or excel spreadsheet, typing in every single entry you see on the App. It would be great if the App can do it automatically (total up the monthly expenditure) for the commuters’ convenience. From the programmer’s perspective, it shouldn’t be that hard to total up (essentially just doing addition)?

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DIY Box to Quiet Aquarium Air Pump

The air pump I am using currently is the Ocean Free Zero Noise Z-1000. It is actually already quite quiet (around 4o-45 decibels measured on a free iPhone app “dBMeter”).

I decided to create a DIY box to further absorb the sounds. Materials used are:

  • Phone box (iPhone box cover used here, but probably any similar sized box works)
  • Scissors (to cut holes for the air tubing and power cord to pass through)
  • Corrugated plastic board (black). Initially I wanted to make a cover, but the pump was too tall to cover it. Hence, I added some corrugated plastic boards to raise the height of the box.
  • Some black foam (I think it was part of the aquarium packaging) to line the inside of the box, for sound absorption.
  • Corrogated plastic board and black foam was also used to make a “base” for the phone box. (I am not entirely sure if this helps or not, just thinking in the line of reducing physical vibrations.)
  • Cloth from old shirt (blue) to line the inside of the corrugated plastic board, again to absorb sound.

In the end, I decided not to have a cover, to prevent overheating. Currently, there should be ample air flow as the box is essentially open top.

Results are quite ok, noticeably softer sound. Approximately around 5 decibels reduction in sound from the “dBMeter” app, to around 35-40 decibels. Probably it is quite hard to go lower than that since even a relatively quiet room is around 20-30 decibels.

Pictures are below:

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Sellfy free account to be discontinued

Just received some news from Sellfy:

Hi there,

We have important news about your Sellfy account and your store https://sellfy.com/mathtuition88

You have been on our transaction fee only plan (Legacy plan) since you signed up for Sellfy. We are truly thankful for being with us all this time!

Due to considerable technical adjustments in our platform and supporting services, we are forced to discontinue the Legacy plan on February 1st, 2020 and switch into supporting subscription-based plans only https://sellfy.com/pricing/. We no longer offer Legacy plan for new users since March, 2016.


Most likely, we won’t be continuing with Sellfy after February 1st, 2020.

Hence, this is the last 1-2 months to purchases math notes/material from our online store: https://sellfy.com/mathtuition88 if you are interested. Thank you for the support!

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2 types of chi-squared test

Most people have heard of chi-squared test, but not many know that there are (at least) two types of chi-squared tests.

The two most common chi-squared tests are:

  • 1-way classification: Goodness-of-fit test
  • 2-way classification: Contingency test

The goodness-of-fit chi-squared test is to test proportions, or to be precise, to test if an an observed distribution fits an expected distribution.

The contingency test (the more classical type of chi-squared test) is to test the independence or relatedness of two random variables.

The best website I found regarding how to practically code (in R) for the two chi-squared tests is: https://web.stanford.edu/class/psych252/cheatsheets/chisquare.html

I created a PDF copy of the above site, in case it becomes unavailable in the future:

Chi-squared Stanford PDF

Best Videos on each type of Chi-squared test

Goodness of fit Chi-squared test video by Khan Academy:

Contingency table chi-square test:

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Ohm Energy Referral Competition (2 Dec 2019 – 2 Feb 2020)

Just to share this Ohm Energy Referral Competition. If you are not a Ohm electricity user, sign up using the promo code OHMREF25CC5A now to begin the competition!

Also read my blog article explaining why Ohm is the best electricity supplier in Singapore: Ohm $20 Promo Code: OHMREF25CC5A.


We would like to thank you again for giving us the highest rating in the Energy Market Authority’s Customer Satisfy Survey. To show our appreciation, we will be rolling out 3 concurrent competitions from 2nd December 2019 with attractive cash prizes up for grabs.

Your Personal Referral code is: OHMREF25CC5A

Do access our Customer Portal Login to verify your referral code.

1. All-in Referral Competition (“All-in”) – All referral registered from the start of the Open Electricity Market soft launch on 1 April 2018 through 2nd February 2020 will be counted towards the prizes.

2. Fresh Referral Competition (“Fresh”) – All referrals registered between 2nd December 2019 through 2nd February 2020 will be counted towards the prizes.

At the end of the competition, the Top 10 referrers from each category, All-in and Fresh, will win cash prizes from Ohm according to the table below.

“Fresh Competition” Cash Prize “All-in Competition” Cash Prize
Top Referrer S$1000 S$1000
2nd Place S$500 S$500
3rd Place S$300 S$300
4th – 5th Place S$200 S$200
6th – 10th Place S$100 S$100

3. Periodic winners – We will also select a winner for six interval periods. The counter will reset every period and we will pick the customer with most referrals registered in that period. In the event of a tie, the award will be divided equally amongst the winners:

Period 1: 02 Dec 2019 to 15 Dec 2019 – S$40 cash prize

Period 2: 16 Dec 2019 to 29 Dec 2019 – S$50 cash prize

Period 3: 30 Dec 2019 to 12 Jan 2020 – S$60 cash prize

Period 4: 13 Jan 2020 to 19 Jan 2020 – S$80 cash prize

Period 5: 20 Jan 2020 to 26 Jan 2020 – S$90 cash prize

Period 6: 27 Jan 2020 to 02 Feb 2020 – S$100 cash prize

For all 3 competitions, eligible referrals must be keyed into the promotion code field at the point of registration as we are unable to retrospectively change or input referral codes. A referral is only eligible if we can detect that it has been applied in our systems and the customer’s transfer is confirmed by SP Services. Any manual credit to an account will not be counted as a referral.

Do visit our existing Referral Programme Terms and Conditions at Refer Us to A Friend and Ohm Referral Competition Terms and Conditions here for more details.

We wish you the best of luck and a great festive season!

Warm Regards,
Team Ohm

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Fixed Ohm vs Ohm Discount

Many people have decided to switch to Ohm electricity, but are still confused which plan to take. The two best plans are Fixed Ohm and Ohm Discount.

Personally, I think Ohm Discount is the better one, with this blog post detailing my calculations: Ohm $20 Promo Code: OHMREF25CC5A.


*Ohm Promo Code: OHMREF25CC5A

After extensive research, I find that Ohm is one of the best alternative electricity suppliers. Choose either Fixed Ohm or Discount Ohm depending on your likings. I chose Discount Ohm as I have a feeling that the tariffs may drop. Fixed Ohm is also very good, and in fact better if tariffs rise.


The blog MoneySmart have also made their calculations and concluded that at this point in time, Discount Ohm is superior to Fixed Ohm.

Ohm Energy’s discount of 25% off is the best in the market, compared to other retailers who are offering only 22% or 23%. Yup, this means your bill will always be 25% less than whatever SP charges, which sounds awesome.

Right now, the tariff is 25.07¢ for Oct to Dec 2019, which actually makes the Ohm Discount plans cheaper than their fixed price plans, quite the anomaly in the electricity market.

Source: https://blog.moneysmart.sg/budgeting/ohm-energy-review/


Simply Ohm vs Market Ohm review

Other than Ohm Discount and Fixed Ohm, there are actually two other plans Simply Ohm and Market Ohm. Without going into too much details, we may just say that these two plans are not nearly as good as Ohm Discount or Fixed Ohm. You may read the MoneySmart article above for more details, basically they are more expensive in most cases for the average consumer.

Conclusion: Ohm Discount is Clear Winner, followed by Fixed Ohm

For the average consumer, it is safe to say that Ohm Discount is the plan you should go for. Both my blog article on Ohm, and MoneySmart comes to this exact same conclusion.

Fixed Ohm may be actually better in the event that tariffs start to rise significantly, but in the near future that does not seem to be happening (based on the trends). Simply Ohm and Market Ohm are very specialized plans targeted at very special cases, currently they are no match for Ohm Discount nor Fixed Ohm.

Do sign up for Ohm now using the promo code below!

*Ohm Promo Code: OHMREF25CC5A

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Melafix Review and Research

Melafix is quite a popular medication in the aquarium hobby, by the company API. Chances are most people have at least heard about it. However, there is remarkably little information on this medication online, and whatever information is scattered and not centralized.


API MELAFIX Fish remedy For Bacterial Infection in Freshwater Aquarium 16-Ounce Bottle

What is Melafix and what is Melafix’s ingredient?

The active ingredient in Melafix is Melaleuca oil at 1.0% concentration. We can easily then see how Melafix got its name. Melaleuca oil comes from the a tree in the Melaleuca genus, which includes the popular “tea tree” from which “tea tree oil” is derived. Note that there is a technicality where “contrary to popular opinion it is not made from the common Tea treeMelaleuca alternifolia, but from Melaleuca leucadendra, also known as the Cajeput Tree” (Wikipedia).

Melafix Research

There seems to be not much research done on Melafix. One of the few research papers is the following:

The use of Melafix on goldfish and clownfish appears to be safe as no adverse effects were noted during the experimental period. The results also showed that Melafix has no effect on the water-quality parameters tested. In vitro efficacy studies were conducted by determining the minimum inhibitory concentration and minimum bactericidal concentration of Melafix on various pathogens. The study revealed that Melafix had no significant bactericidal or inhibitory effect on any of the pathogens tested. This observation suggests that anecdotal benefits of Melafix are not owing to antibacterial activity.

Source: https://www.sciencedirect.com/science/article/abs/pii/S1557506315000269

The above paper seems to show negative results (no antibacterial activity of Melafix), but at least there is no harmful effects on the fish nor water parameters. The effect of Melafix may not be due to the antibacterial activity per se, but possibly the healing and regenerative aspects of it, or boosting the fish’s immune system and regrowth of tissue.

A paper showing positive effects of Melafix is the following:

In particular, a combination treatment of Melafix® and Pimafix® was highly effective at reducing in vitro survival of parasites from 15 to 2 h and eradicating 95% of gyrodactylids in vivo. The unexpected high efficacy of this combination treatment is likely explained by the high content of terpenes and phenol propanoids in the cajuput and West Indian bay oils, as well as the anti-helminthic properties of the emulsifier Crovol PK 70. Hence, Melafix® and Pimafix® effectively reduce gyrodactylid burdens on fish, increasing the chances of efficient disease control in ornamental fish.

Source: https://www.int-res.com/articles/dao2015/115/d115p129.pdf

Yet another paper is not on Melafix, but on its active constituent Cajeput oil:

Main antibacterially active agents obtained from plants-Cajeput essential oil–1,8 cineol, linalool, alpha-terpineol and terpinen-4-ol, for example from Melalleuce leucadendron (Myrtaceae) as well as essential oil from Ocimum gratissimum (Labiatae) were combined in tests in vitro with selected antibiotics. Above mentioned plant products were found to be effective medicaments for local application in modern medical practice. Combinations with antibiotics potentiated their therapeutical action. On the basis of tests in vitro the synergistic action of these two kinds of medicaments, i.e., preparations traditionally used for a few last decades–antibiotics–might be well applied for therapeutical needs.

Source: https://europepmc.org/abstract/med/1293213

Hence, the above link supports the view that Cajeput oil (active ingredient of Melafix) does have antibacterial properties!

Anecdotal Evidence of Melafix

Judging by Amazon reviews (https://amzn.to/34G4Ubr), many people do claim that Melafix works in curing their fish of fin rot, popeye, and various other ailments.

The biggest advantages of Melafix are as follows:

  • Does not kill beneficial filter bacteria
  • Does not stain water (colorless)
  • Shrimp safe
  • Snail safe
  • Plant safe
  • All natural

The most “powerful” medication is of course fish antibiotics, but that is the last resort as there are many side effects of antibiotics, including possible wiping out all filter bacteria, and development of resistant bacteria.

An example of fish antibiotics is API General Cure, which is a very powerful fish medication that can treat very serious diseases such as “hole in the head”.


API GENERAL CURE Freshwater and Saltwater Fish Powder Medication 10-Count Box

Melafix Reviews

The below is an amazing case of recovery from popeye (eye dangling out) treated by Melafix.

It was absolutely the worst case of Popeye I have ever see with the eye protruding almost 3/8 of an inch and hanging down.. It was so nasty looking that the wife & kids wouldn’t go near the tank as the sight made them feel sick.. I was nearly to the point of putting it down as I figured it would surely get worse and if there was some type of infection involved, I didn’t want to contaminate the tank.

I decided to treat the tank with a product made by API called Melafix. This is an antibacterial made from the extract of Tea Trees. I only used 1/2 the recommended dose as to not create any major impact to the rest of my tank and system.

Long story short, within 2 days of the treatment I thought I noticed a change and saw the fish actually eat. I treated the tank again after 3 days and the eye definitely improved.. After the second treatment I just watch with amazement as the fish made a complete recovery within two week with no sign what so ever the initial problem.

Source: https://www.reef2reef.com/threads/severe-pop-eye.261687/

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Ohm $20 Promo Code: OHMREF25CC5A

Singapore Maths Tuition

*Ohm Promo Code: OHMREF25CC5A

After extensive research, I find that Ohm is one of the best alternative electricity suppliers. Choose either Fixed Ohm or Discount Ohm depending on your likings. I chose Discount Ohm as I have a feeling that the tariffs may drop. Fixed Ohm is also very good, and in fact better if tariffs rise.

Benefits of Ohm:

  1. Their discount off tariff rate is currently the best at 22% (Update: discount is now 25%)!
  2. Very smooth transition as they are partners with SP group. For instance, there is no need for any paper work nor additional payment of deposit.
  3. Very nicely done website. Signing up is immediate, just fill in some personal details online and you will get the Welcome Email in less than 15 minutes.
  4. Ohm absorbs the transmission loss. (Basically electrical energy is lost as heat while travelling through the cable, Ohm absorbs this and charges consumer…

View original post 238 more words

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Ohm Electricity Review

I have been using Ohm as my electricity supplier since 01 Nov 2018. So far everything has been going 100% super smoothly. Cheaper electricity bills, and integrated billing system with SP services. Ohm has been processing everything efficiently in the background.

Their website design is super sleek and modern. Very easy to use.

*Ohm Promo Code: OHMREF25CC5A

Highly recommend everyone to go with Ohm as their electricity provider. Just spend 10 minutes of your time to switch now, the potential savings in the long run can add up to hundreds if not thousands of dollars. Good thing is everything is online, there is no need to go down to any location nor any physical paper work. It is also applicable to citizens, foreigners, PR, basically anyone who lives in Singapore.

If you have an extensive network of friends/relatives, their referral network is also amazing for you. You will get $20 off your electricity bill (and your friend too), with no upper limit and no expiry date. Imagine, if you have 500 loyal facebook friends who sign up through you, you will get $10k off your electricity bill, which may be enough to last your entire lifetime in most cases.

See my detailed review and also promo code here: Ohm $20 Promo Code: OHMREF25CC5A

*Ohm Promo Code: OHMREF25CC5A

After extensive research, I find that Ohm is one of the best alternative electricity suppliers. Choose either Fixed Ohm or Discount Ohm depending on your likings. I chose Discount Ohm as I have a feeling that the tariffs may drop. Fixed Ohm is also very good, and in fact better if tariffs rise.

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Aquarium Salt dosage for Planted Tanks

As a general rule of thumb start with 1 tablespoon per 5-7 gallons of aquarium water. This is a safe dose for all fish and plants including salt sensitive corydoras.

Source: https://www.ibcbettas.org/aquarium-salt-the-healthy-preventative-v-2-0/

In terms of milliliters, it is approximately:

15 ml of salt for a 20 liter tank (5 US gallon tank)

5 ml of salt for a 7 liter tank (2 US gallon tank)

There are various arguments whether cooking salt can be used in place of aquarium salt. Personally, I use normal cooking salt (non-iodized) and so far it works fine (no fish nor shrimp nor snails have died).


Example of a 5 Gallon tank:

Example of a 2 Gallon tank:

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Oven Power Trip

Bosch Oven Power Trip

Apparently, it is quite common in Singapore (and other tropical countries like Malaysia, Indonesia) that the electric oven cause a power trip (or short circuit) due to the high humidity. Basically, the heating element tends to attract moisture, and if the moisture accumulates too much it will cause a power trip. Since the humidity in the tropics is very high, the chances of this happening is also quite high.

There are two kinds of oven power trips:

  1. Oven power trips after a certain time (e.g. 5 minutes) from turning it on
  2. Oven causes power trip immediately upon switching on power

Clearly, Case 2 is more serious than Case 1. There is a simple solution for Case 1 Oven Power Trips that you may try: first switch on the oven to low temperature (50 degrees Celsius) to dry out the moisture. Only after reaching that temperature, then slowly turn up the temperature. This may solve your problem to stop the oven power trips.

For Case 2 Oven Power Trips, it is more serious, most likely you will need to call a professional to replace the heating element. For my case, I called the Bosch service repair on Friday, and they were able to come on Monday to repair the oven. It took less than half an hour, and it was free since my oven was still within the two year warranty period.

How to Prevent Future Oven Power Trips

To prevent future power trips or short circuits from occurring in the future, the ideal case is to use the oven more frequently (in all modes!). By “in all modes” I mean that you should use all of the modes, including the upper heater, lower heating element, and/or fans. This was emphasized by the Bosch repair man. (Previously I was only using one single mode, the “fan” mode.)

At the very least, one should still use the oven at least once a month (even if it is empty inside), to dry out the moisture, for a period of 10 to 30 minutes (recommended by many online sources as well as the Bosch repair man).

 


Bosch HBL5451UC 500 30″ Stainless Steel Electric Single Wall Oven – Convection

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Popular packages in R and Python for Data Science

Most of the time, users of R and Python will rely on packages and libraries as far as possible, in order to avoid “reinventing the wheel”. Packages that are established are also often superior and preferred, due to lower chance of errors and bugs.

We list down the most popular and useful packages in R and Python for data science, statistics, and machine learning.

Packages in R

  • arules
  • arulesViz
  • car
  • caret
  • cluster
  • corrplot
  • ggplot2
  • lattice
  • perturb
  • psych
  • readr
  • recommenderlab
  • reshape2
  • ROCR
  • rpart
  • rpart.plot
  • tidyverse

Python Packages

  • factor_analyzer
  • math
  • matplotlib
  • numpy
  • pandas
  • scipy
  • seaborn
  • sklearn
  • statsmodels
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Recall & Precision vs Sensitivity & Specificity

Other than accuracy rate, there are various metrics for machine learning to measure how “accurate” the model is.

Some popular ones for binary classification are sensitivity (true positive rate) and specificity (true negative rate).

In computer science, recall and precision are also common metrics.

It can be quite confusing to remember offhand what each metric means, and how they are related.

To summarize, the following are equivalent (for binary classification):

sensitivity = recall of positive class

specificity = recall of negative class

Sample source: https://onlinelibrary.wiley.com/doi/pdf/10.1002/cmdc.201700180

Other than the above metrics mentioned, there are also many other metrics, such as F1 score, etc.

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LaTeX Table Style Guidelines

Drawing LaTeX tables is well known to be quite troublesome. Fortunately, there are some excellent tools online to generate LaTeX code for tables, e.g. Convert Excel to LaTeX.

Even after that, there are some stylistic dilemmas, for instance how many borders to include in the table?

I found this powerpoint slide that summarizes very nicely what to do (and what not to do) to create a nice LaTeX table. Source: https://inf.ethz.ch/personal/markusp/teaching/guides/guide-tables.pdf

Most Important Guidelines for Making Tables with LaTeX

  • Avoid vertical lines
  • Avoid “boxing up” cells, usually 3 horizontal lines are enough: above, below, and after heading (see examples in the guide above)
  • Avoid double horizontal lines
  • Enough space between rows
  • If in doubt, align left

The above 5 guidelines were invaluable and cleared up my doubts on how to make a nice table using LaTeX.

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Express vs Normal Academic for borderline PSLE score

Just to share this old post on the dilemma of choosing Express vs Normal Academic (for borderline PSLE scores). Both choices have pros and cons and hence must be pondered carefully.

Singapore Maths Tuition

For students scoring in the borderline of around 190- 200 PSLE score, there is a dilemma of going to Express stream in a neighborhood school, or Normal Academic N(A) in a more established school. Note that even good schools like Anderson, ACS (Barker) do have N(A) streams.

Here are some advices from people who have experience:

Source: Hardwarezone

First opinion says that N(A) in a good school is better:

“NA in good school

i myself is living example

in the end my parent chose express at neighborhood school

in the end that school is a s**** school. i cannot keep up with studies.

by secondary 2 i drop to NA

then stuck with the lousy neighborhood school and my whole life got ruin until now

if i can go back time i sure chose NA at good school”

This post (from Hardwarezone) made a good argument of why express stream…

View original post 606 more words

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Ways To Turn Writing Inspiration Into Money

A good writer is gifted with imagination and the ability to capture the imagination of readers. A lot of these writers begin writing as a hobby. However, some have found a way of converting this hobby into an economic activity that brings revenue. You may take up freelance writing job or engage in other activities that will pay for the effort and skill you already possess.

Image

Writers have multiple options when looking for places to apply their skills. The options will depend on personal interests, available time, and the willingness to venture into a particular field, among other factors. Here are the options available to talented writers who wish to make a few dollars from their skills. 

Blogger

Open a blog where you share regular content with followers and readers. A lot of blogging platforms have emerged online that writers can use to launch their careers. A writer may also choose social media as a starting point for his or her blogging career. 

A blogger needs to identify the perfect niche for his or her blog. It should come out of interest so that your articles are insightful to read. Choose a unique style that your readers can identify with and always look forward to reading your articles. 

Writer

Individuals, businesses, and entrepreneurs are looking for the skilled persons who can tell their stories in writing. It means that a writer will never lose the opportunity to make money. You must possess the best skills that will enable you to meet your client’s expectations. 

Choose a niche and master the content needs for the area. For instance, a product reviewer will know what potential customers are looking for in a review. A content writer also understands the rules for producing the best description of merchandise. Your prowess in a given area will determine the number of clients who come looking for your services. Expert writers earn handsome returns. 

Editor

Editing is a skill that few have mastered. It requires a professional who understands the rules of writing and has a third eye to spot subtle mistakes. Editing eliminates errors that would distort communication leading to misreporting or misinformation. Experienced writers can take up editing roles and enjoy excellent returns. 

Ghostwriter 

Some individuals and institutions lack the time or skill to write but would desire to produce scripts and books. Ghostwriters are paid to complete the task but not take credit for the work. You have to master writing skills in a specific area like blogging, books, and such other genres. 

Trainer 

A lot of people desire to improve their writing skills. They are looking for mentors and trainers who can help them sharpen their writing skills. Since you understand writing and have specialized in a particular area, you can teach other persons looking for guidance or assist them in improving their skills. 

The amount of money earned from writing prowess depends on your area of choice and the ability to monetize the platforms you use. The money can be earned online or offline. Adapt to the latest writing tricks to improve your chances of making more money. 

 

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Singaporean van Gogh – Mr Sim Kah Lim

Sim Kah Lim 2019 Update
Found 2 more excellent updated videos on Mr Sim Kah Lim, the artist.

Singapore Maths Tuition

This is an amazing story of an amazing artist. His passion for painting is so great, according to his therapist he wants to paint 24/7 without eating or sleeping. I find his paintings of Singapore River very good.

“Bumboats on Old Singapore River”

“Singapore River of a Previous Era”

SINGAPORE: For nearly 35 years, Mr Sim Kah Lim’s world has been the walls of his ward at the Institute of Mental Health (IMH).

Outside, changes have swept the landscape, old buildings falling and new ones rising – skylines and shorelines of a 21st-century nation transformed.

But in his mind’s eye – and in his bold-stroked acrylic and watercolour paintings – Mr Sim’s homeland is one where bumboats still crowd the Singapore River, ferrying goods and passengers; and where Chinatown’s open-air markets thrive and its five-foot ways are bustling with locals, not tourists.

They are pictures, frozen in time and memory, from…

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Narrow Leaf Java Fern vs Normal Java Fern

It is well known that the Java Fern has different “varieties” — such as “trident”, “Windelov”, “Narrow Leaf” and “Needle Leaf”.

I kept normal Java Fern, as well as “Narrow Leaf” Java Fern in Singapore, at a temperature of around 29 to 30 degrees Celsius (85-86 Fahrenheit).

I found that the Normal Java Fern does well (nice green color, and grows baby plantlets), but the “Narrow Leaf” Java Fern does not do well (becomes browner and even blacker by the day).

I checked online and at least four other people have experienced this:

I think cooler temperatures might be the answer. My narrow leaf in syd are lush green and pearling like mad in temps of 25 celsius. In KL, 28-29 celsius, they grow a little, turn brown sometimes and are a bit of a hassle to keep. My normal java fern does well in any temps/conditions, just the narrow leaf, more demanding. Has anyone grew nice long narrow leaf in warm temps? Those in LFS have them in air conditioned rooms.

Source: http://www.aquaticquotient.com/forum/showthread.php/21779-Narrow-leaf-Java-Fern


Narrow Leaf Java Fern does better in cooler temperatures (around 25 degrees Celsius)

Other anecdotal evidence that Narrow Leaf Java Fern may do better in cooler waters:

Wes,

I’ve had a lot of success with Java Ferns and Narrow Leaf Java Ferns (NLJF) in my tank.

My tank is high-light (288Watts for 80gallon) and has lots of CO2 (3bps). I dose it with TMG almost every week. I tie the JF on driftwood and also bury them in my substrate, either way it grows well. Kwek Leong did share with me that growing them in substrate will produce longer leaves for NLJF and that holds true in my tank. I place them very new my water outlet as I read somewhere that the JF thrives in that environment. Also, I have a chiller that keeps my water temp at around 24.5-25.0C.

Hope this helps!

Cheers,

Roger

Another post:

I knew of a tank that grow Narrow Leaf Java Fern very well and the conditions are like what Roger has too. Under these conditions, they grow very rapidly and the leafs are jade green and very clean (no spots at all).

Yet another post:

I used to have prolific growth of Narrow Leaf Java Ferns in my tank. I don’t think CO2 injection is necessary but the ferns probably do better under low light and cold water.

Source: http://www.aquaticquotient.com/forum/showthread.php/49107-Best-conditions-for-Java-Fern

Methylene Blue and Narrow Leaf Java Fern

Something else interesting that I found out is that methylene blue seems to affect narrow leaf Java Fern negatively, but not normal Java Fern. Basically, the Methylene blue seems to stain the narrow leaf Java Fern, and lead to its demise. I tried this out inadvertently while dosing my fish tanks with methylene blue to cure ich.

The Narrow Leaf Java Fern is on the right of my fish tank in the video below (it was still in an ok state at that time):


I think the conclusion is that Narrow Leaf Java Fern is a slightly more demanding plant when it comes to temperature (does not do well above 27-28 Celsius). Due to global warming, many countries in the tropics are now stuck with 30 degrees Celsius temperature almost all year round, hence the normal Java Fern may be a better choice.

It also sort of makes sense in terms of plant biology. Usually plants with “thin” leaves tend to be those that live in colder/cooler weather such as pine trees. While plants with big wide leaves are those that live in hot tropical weather (such as banana tree). Using this “logic”, I would suppose that needle leaf Java Fern also does better in cooler waters.

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How to Balance College and Work and Find Some Spare Time

No one said it would be easy, but if you’re looking for ways on how to balance college and work, use these tips to improve time management.

A recent survey revealed that the majority of students work while attending college. Learning how to balance college and work on a full-time basis is your key to achieving success with less student loan debt.

According to this survey, 24.4% of students claimed they were fully responsible for funding their education. If your dream depends on you getting a degree, please know that your goal is still within reach.

Attending school and working full-time isn’t easy, but any effort you invest in this endeavor will pay off big time. You, too, deserve to feel the pride of graduating with a degree.

Here are some tips on how to balance work and college full-time.

How to Balance College and Work: Time Management

Knowing how to balance work and college means mastering time management. Developing time management skills involves planning and budgeting your time well. When you have 2 schedules to juggle, you must keep track of both to succeed.

Make sure you either write down your work hours or mark them on your phone’s calendar. Use a college schedule maker to create a visual reminder of your class schedule.

Print several copies of this schedule, including a copy to carry with you and another copy to hang up in your workspace.

Designated Workspace Hours

Anyone who’s aware of how to balance school and work in college has a designated space where they complete their work. This space is organized, clean, and stocked with supplies. It’s also free of distractions, so getting work done is more doable there.

A designated workspace like this helps you be more productive. Once you get into the habit of doing schoolwork there, your brain starts associating that space with getting homework done. Then simply entering this workspace will kick your brain right into “homework mode.”

Carve out time that you’ll commit to spending in your workplace. During this time, you’ll study and complete homework. School is just as important as work, so you need to devote time to it.

This way, you won’t have to rush and can work on this next tip.

Sleep Schedule and “Me” Time

Make sure you maintain a regular sleep schedule. Also, try to enjoy some “me” time whenever you get the chance. Your schedule is already packed, so there’s no need to cram more stuff into your day.

Sure, caffeine will help you stay awake. But no amount of caffeine will energize you as much as a good night’s sleep can.

Work on your assignments as soon as possible instead of procrastinating. Getting work done on time reduces your need to rush or pull an all-nighter.

You Are a Success in Progress

The CDC recommends that you get at least 7 hours of sleep per 24-hour period. You can’t truly know how to balance college and work if you’re not getting enough sleep.

If you do pull an all-nighter, make sure you get sleep as soon as possible. An erratic sleep schedule will eventually hurt your work/academic performance.

Give yourself some credit⁠ and check out our resume and networking tips. It’ll improve your chances of landing a better job.

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Bend It Like Beckham: How to Become a Pro Soccer Player

How to Become a Pro Soccer Player

Ever wanted to bend it like Beckham? Turns out, you can with the right training and dedication. Read on to learn how to become a pro soccer player.

Sure, a lot of people dream about becoming a professional athlete. But, most of them don’t have what it takes to go pro and wind up giving up on their dreams.

Becoming a pro soccer player requires a little bit more than a love for the game; it takes a lot of hard work, patience, and determination.

If you think you have what it takes to make it in the big league, but aren’t sure where to begin, we’re here to help you chart your course.

Here’s everything you need to know about how to become a professional soccer player.

Be Ready to Dedicate Yourself

If you’re serious about becoming a professional soccer player, you’re going to need to be ready to give your life over to your sport.

In the years leading up to and during your pro career, you’re going to need to eat, sleep, and breathe soccer. Your body is now your most important tool, and you’ll need to do everything you can to hone it and mold it into a soccer-playing machine.

You’ll need to put together a strict training regimen, and spend a few hours every day practicing.

Outside of training, you’ll need to change your eating and sleeping habits to make sure you’re taking proper care of your body. That means giving up late nights and junk food.

If you think you can handle molding your life around your sport, you can begin to pursue your professional career.

Join a Club or a Team

You can’t walk up to a recruiter and insist you can play at a professional level. You’re going to have to prove it. And, the best way to show off your soccer skills is by joining a local team or a club.

Playing minor league or college level soccer is one of the best ways to get noticed on the field. That said, playing university sports can pose the additional challenge of balancing classes on top of your practice time.

If you make your university’s team, you’ll want to sit down with a college schedule maker to plan your classes and study time around your soccer career.

Joining a team will also help you work on your communication and teamwork. These skills are essential when playing a professional level sport.

On top of that, a team will have the resources available to help you get in touch with club owners and recruiters.

Train On and Off the Field

If you want a chance at going pro, you’re going to need to train outside of team practices.

Work with your coach or professional trainer to construct a good crosstraining program. You’ll also want to go over the best activities you can do to help your body recover on your rest days.

Sticking to a rigorous training program can be tough. But, all your hard work will be worth it the first time you don your pro uniform.

Build Your Network

Finally, like with most careers, it’s not always about what you can do, it’s about who you know.

Go to networking events, talk to your coaches about your goals, and prepare a highlight reel to send out to various clubs and recruiters.

Building a network is one of the best ways to bring your pro soccer dreams to life.

Becoming a Pro Soccer Player

If you want to become a pro soccer player, the most important thing you can do is maintain belief in yourself and your goals.

Reaching the professional level can take years. And during that time you’re probably going to face a lot of rejection. But, if you never doubt yourself and keep working toward your goal, you’ll eventually reach it.

Are you looking for more advice on how to take your game to the next level? We’ve got you covered.

Check out the rest of our blog for more helpful articles today!

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Fish at Yale-NUS Eco pond

Some very interesting fish (South American cichlids?) at the Yale-NUS Eco-pond. It is quite an unknown place, located deep inside U-Town. Not many people know of its existence. Do check it out if you pass by NUS.

At around the 1:45 mark in the video, you can see some juvenile cichlids eating algae growing on the rock.

Some photos of the Yale-NUS Ecopond:

The pond is behind this large circular fountain.

 

There is also this rare tree (supposedly the only one in Singapore) right behind the pond, called “Margaritaria indica”. I think only expert botanists can tell what is so special about this tree. To laymen (like me), it looks like any ordinary tree.

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How to make work-life balance work (TED talk)

Quotes from the talk:

  • “People are working long hard hours at jobs they hate, to earn money to buy things they don’t need, to impress people they don’t like”

A book by the same speaker:


Fat, Forty, and Fired: One Man’s Frank, Funny, and Inspiring Account of Losing His Job and Finding His Life

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Amazing method to unblock stuffy nose

Added another great way to unblock nose. This is a new method called Nasal Septum Mobilization invented by Dr Alan Mandell.

Singapore Maths Tuition

Out of all the methods I checked on YouTube, this method seems to be the most effective in terms of instantly unblocking your nose.

Basically pinch your nose and sway, until you are almost out of breath, then breath in through your nose. I find it very effective.

This method is very good also: Nasal Septum Mobilization invented by Dr Alan Mandell. It is quite a novel method, so far I have only seen it on his YouTube channel and not anywhere else. I think it may work for people with Deviated Septum as a natural remedy. Basically, the way it works is by moving the septum so as to create a “motion” to unblock the nose.

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LaTeX Horizontal Flowchart (Workflow)

Source: https://tex.stackexchange.com/questions/368482/one-horizontal-line-flow-chart?rq=1

Just found an excellent source on how to draw a simple (slightly fanciful) horizontal flowchart using LaTeX (TikZ).

The output is very neat:

The code is reproduced here (in case the original source gets deleted):

\documentclass[tikz, margin=3mm]{standalone}
\usetikzlibrary{arrows.meta,
                chains,
                positioning,
                shapes.geometric
                }
% for fancy looks of data storages
\begin{document}
    \begin{tikzpicture}[
    node distance = 5mm and 7mm,
      start chain = going right,
 disc/.style = {shape=cylinder, draw, shape aspect=0.3,
                shape border rotate=90,
                text width=17mm, align=center, font=\linespread{0.8}\selectfont},
  mdl/.style = {shape=ellipse, aspect=2.2, draw},
  alg/.style = {draw, align=center, font=\linespread{0.8}\selectfont}
                    ]
    \begin{scope}[every node/.append style={on chain, join=by -Stealth}]
\node (n1) [disc] {Training\\ data};
\node (n2) [alg]  {Learning\\ algorithm};
\node (n3) [mdl]  {Model};
\node (n4) [disc] {Test\\ data};
\node (n3) [mdl]  {Accuracy};
    \end{scope}
\node[below=of n2]  {Step 1: Training};
\node[below=of n4]  {Step 2: Tresting};
    \end{tikzpicture}
\end{document}
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Chinese Tutor (has experience in tutoring NYGH/RGS/RI students)

Singapore Maths Tuition

Chinese Tuition Singapore
新加坡华文补习老师
Tutor: Ms Gao (高老师)

Ms Gao is a patient tutor, and also effectively bilingual in both Chinese and English.

A native speaker of Mandarin, she speaks clearly with perfect accent and pronunciation. She is also well-versed in Chinese history, idioms and proverbs.

Ms Gao is able to teach Chinese at the Secondary school level (Chinese and Higher Chinese). She will teach in an exam-oriented style, but will also try her best to make the lesson interesting for the student.

Ms Gao has taught students from: Nanyang Girls’ High (NYGH), RGS, RI, and other schools.

Contact:

HP: 98348087

Email: chinesetuition88@gmail.com

Website : https://chinesetuition88.com/
(Preferably looking for students staying in the West side of Singapore)

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Amazing method to unblock stuffy nose

Out of all the methods I checked on YouTube, this method seems to be the most effective in terms of instantly unblocking your nose.

Basically pinch your nose and sway, until you are almost out of breath, then breath in through your nose. I find it very effective.

This method is very good also: Nasal Septum Mobilization invented by Dr Alan Mandell. It is quite a novel method, so far I have only seen it on his YouTube channel and not anywhere else. I think it may work for people with Deviated Septum as a natural remedy. Basically, the way it works is by moving the septum so as to create a “motion” to unblock the nose.

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Cai Yun Zhui Yue Piano Sheet Music (PDF)

This is a classical piano tune that is masterfully transcribed (by arranger Wang Jianzhong 王建中). In English, it is also called “Colourful Clouds Chasing the Moon”. In Chinese, it is called 彩云追月.

The transcription is really very nice, the harmony and the melody of the original tune is preserved and even enhanced. Few piano scores for Chinese music can achieve this effect.

The sheet music (or piano score) is originally from http://www.everyonepiano.com, we simply convert to PDF for the convenience of those who are seeking it:

PDF Sheet Music Score for Cai Yun Zhui Yue: Cai Yun Zhui Yue PDF

I checked that this version is the same as the one performed by Li Yundi:

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