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Is CCA important in JC?

CCA enhances the overall portfolio of the student, but at the end of the day, the foundation of the portfolio is still ‘A’ levels.

Especially for local uni admission, CCA is not really taken into consideration.

For top tier scholarships / top local courses, it would require good ‘A’ level results + good CCA though.

Question from JC1 student on Kiasuparents: “but the school focuses a lot on other areas of development like CCA and etc so i want to know that is it really that important cos i don’t feel like taking part in all these activities anyone got experience in these areas??”:

I would think for majority of students, it would be better to prioritize to get:
Good ‘A’ level results & Mediocre CCA
rather than Mediocre ‘A’ level results & Good CCA.

Of course, if one is all-rounded, one can aim for the ideal goal of:
Good ‘A’ level results & Good CCA.
(To be realistic, not everyone can achieve that…)

The only exception is if one’s CCA results is so excellent (e.g. win top award at national or international level), it can potentially lead to special case arrangements for university admission even with poor ‘A’ level results. Note that this is probably a 0.1% case scenario for top CCA performers, a typical “President of CCA group” position may not suffice, let alone an ordinary member of the CCA.

CCA training hours can vary widely among different CCAs. I have seen students with CCA that can last up to 9pm or later on weekdays. This can be extremely tiring considering that school starts at 7am next day. Someone succinctly summarized on Kiasuparents that: “In conclusion, the minimal you need to do is to choose a CCA with only one session per week and make yourself physically present on that day.

Physics Exam Papers

Free Exam Papers (Physics)

Do check out our main page on Free Exam Papers as well!

‘O’ Level / Prelim Physics Exam Papers

  1. Maths Physics Hub
    Quite a large collection of recent (2017) Physics Exam Papers, ranging from top schools (ACS, Nan Chiau, etc.) as well as neighborhood schools (Fuhua, Zhonghua, Xinmin, etc.).
  2. Test Papers Free
    A large collection of Pure Physics as well as Combined Science (Physics) exam papers. No login is required, however the interface is a bit messy. But you should be able to find quite a few Physics Test Papers.
  3. https://testpapers.com.sg/
    A treasure trove of school papers (including Physics Pure and Combined, Express and Normal Academic (NA)). Needs login to download.

‘A’ Level / Prelim Physics Exam Papers

  1. http://tinyurl.com/holygrailrepo2
    This weirdly titled Google Drive (“Electric Boogaloo”) contains a mega-database of JC Prelim papers for Physics. Exam papers ranges from H1 to H3, and from the years 2008 to 2019.

Note: The Free Physics Test Papers listed above are hosted on external sites independently. Sometimes, the site may be down or the link may be broken.

 

Poll Results: How many marks to get ‘A’ for H2 Math

Almost 100 people have voted on the poll on “How many marks to get ‘A’ for H2 Math“.

The results show that the majority (57.6%) of voters think it takes at least 75 marks to get ‘A’ for H2 Math. Notably, a significant percentage (27.17%) think that it takes 80 marks and above to get ‘A’ for H2 Math.

Students who have taken the H2 Math exam can actually estimate the cut-off point for ‘A’ grade quite well. Basically, the worked solutions are typically released by seniors/tutors, and students can estimate their own marks rather easily. Then, they can compare with their actual grade received.

Nevertheless, the above is just a poll, it may not be 100% accurate and it also depends on the difficulty of that year’s exam. An easier exam would naturally lead to a higher mark required for ‘A’ grade for H2 Maths.

Is there bell curve for ‘A’ levels?

This is a tricky question. The technically correct answer is that there is no bell curve, but there is a similar thing called “grade boundaries”. It is like certain schools saying that they have no Midyear Exam, but there is a “Block Test”. Read more about whether there is bell curve for ‘O’ and ‘A’ levels.

WordPress New Editor Review

WordPress has released a new editor called “Gutenberg”. While WordPress should definitely be applauded for its new innovation, personally I find it more convenient to just use the Classic editor instead. Perhaps it is just a matter of habit. Basically, I find the learning curve not justified for basic blog posts. I would need to see a truly impressive application of the “blocks” in order to switch over to the new editor.

WordPress New Editor Disable

If you search on Google, one of the most popular search terms is actually “wordpress new editor disable”! This shows that many people are actually trying to disable the new WordPress editor completely! Personally, what I do is I first create a new post (by default it is the new editor), save post, and then edit it using the Classic Editor.

Do vote in the poll above and it would be interesting to see the results!

Aquatic Avenue Review

Aquatic Avenue Facebook: https://www.facebook.com/AquaticAvenue/

I have been there personally once. Had a good impression as they had exotic fish not commonly found elsewhere. (For example, Gertrude Rainbowfish (Pseudomugil gertrudae), Celestial Pearl Danio, etc.) They are also specialized in shrimp and plants. It was my first time seeing the Gertrude Rainbowfish, and I was absolutely fascinated.

The guy (not sure of his name) there was clearly knowledgeable about fish (much more knowledgeable than me). Taught me a bit about how to keep Celestial Pearl Danio. The owner was friendly, and can see that he is passionate about the fish and aquarium hobby.

Also, ordered plants online from them. Their plants are of good quality, and labelled correctly. For example, my Ludwigia Super Red was bought from them. It was grown submersed (underwater), and was of good quality (had roots, leaves are bright red color).

For comparison, many other aquarium shops in Singapore don’t label their plants, as well as sell non-aquatic plants. (I as a beginner was “scammed” twice, once with Malayan Aqua Fern, and another time with Alternanthera Sessilis.) Had they been labeled, a simple Google check would suffice to know that they are non-aquatic.

Currently, they do have a free delivery promotion (no minimum purchase), so do check them out on their Facebook or online store.

Overall, I would say that they are more of a premium aquarium store, they have great quality and range of rare exotic fish and plants.

There is one negative review of them in a blog online (dated 2014), that was certainly not my experience in 2019. In 2019/2020, my review of Aquatic Avenue is definitely positive.

Overall Review of Aquatic Avenue:
Very Good!

  • Exotic and rare fish
  • Exotic and rare plants (properly labeled and grown)
  • Quality fish and plants
  • Premium high-end aquarium shop, prices are still affordable
  • Friendly and knowledgeable staff

If you decide to visit them (after the virus situation stabilizes), do check out the nearby Redhill coffeeshop as well. There are many vintage hawker food there which are of good quality, and at very affordable prices.

Easy Floating Plant: Salvinia

This plant Salvinia (to be precise Salvinia Molesta or Giant Salvinia) is a super easy floating plant. It has 3 forms: Primary, Secondary, Tertiary Forms. I started with Tertiary Form Salvinia, and now have a lot of Primary Form Salvinia, as well as a few Secondary Form Salvinia.

I find that Salvinia is an easy floating plant because:

1) It only requires medium light

2) It has 3 forms and will evolve to the form that is most suited for your tank. The Tertiary Form is usually for outdoor ponds.

3) It is ok with getting a bit wet. Many other floating plants must be completely dry or else they may rot.

4) It has short roots. Hence, there is no need to trim its roots.

5) Easy to remove if you don’t want it. Most of its leaves are linked together. Hence you can remove all the leaves in a few grabs. This is in contrast to duckweed, which is notorious for being hard to remove.


I find that the Primary Form of Giant Salvinia is quite similar to Salvinia Minima, and the Secondary Form of Giant Salvinia is quite similar to Salvinia Natans! Could they be the same species?

Tropica also sells this version of Salvinia which they call it Salvinia auriculata.


24 Water Spangles (Salvinia Minima), Live Aquarium/Aquatic/Floating/Pond/Beginner Plant by G&Z

Key Topics for IP Additional Mathematics

The following are some of the most important topics for Integrated Programme (IP) Additional Mathematics. Also applicable for the usual ‘O’ level Additional Mathematics.

Notice that Secondary 3 topics are very important as well, for the final Promo or ‘O’ levels. This can be a major problem for students who only start to study seriously in Secondary 4 — it can be a tough job to catch up with the important Secondary 3 topics.

Secondary 3 topics

  • Binomial Theorem
  • Indices and Logarithms
  • Coordinate Geometry of Circles
  • Linear Law

Secondary 4 topics

  • Trigonometry: R formula and Graphs
  • Differentiation and its Applications
  • Integration and its applications (including area under the curve)

Motivational Quote: Work can never be completed

The following are some motivational quotes by Dr. APJ Abdul Kalam, former president of India. The source is from Pinterest. I have also translated some of the quotes into Chinese.

I believe the quotes make perfect sense! Hope you find it motivational and useful as well.


Love your job but don’t love your company, because you may not know when your company stops loving you.

热爱你的工作,但不要爱你的公司,因为你不知道公司何时停止爱你。


Work is a never-ending process. It can never be completed.

工作是一个永无止境的过程。 它永远无法完成。

Interest of a client is important, so is your family.

客户的利益很重要,您的家人也很重要。

If you fall in your life, neither your boss nor client will offer you a helping hand; your family and friends will.

如果你在生活上遇到挫折,老板和客户都不会给你帮助;您的家人和朋友会。

Life is not only about work, office and client. There is more to life. You need time to socialize, entertain, relax and exercise. Don’t let life be meaningless.

生活不仅是围绕着工作,办公室和客户。 生命还有更多意义。 您需要时间进行社交,娱乐,放松和锻炼。 不要让生活变得毫无意义。

You did not study hard and struggle in life to become a machine.

你努力学习和奋斗,不是为了成为一台机器。

Easy Red Low Tech Plant: Ludwigia Super Red

Ludwigia Super Red, also known as Ludwigia Palustris or Ludwigia sp. red (mini) is one of the easiest low tech red plants. Due to its small size, it is suitable for nano tanks (with trimming).

It is rated “easy” by Tropica. In comparison, most other red plants are rated “Medium” or “Advanced”.

I am trying out this low tech easy red plant without CO2. Future updates will be posted on this page as well.

Day 1:

Ludwigia Super Red 1st day in low tech tank!

Day 2:

This is the second day of growing Ludwigia Palustris, also known as Ludwigia Super Red (sp. red mini). I think new growth has already appeared at the top of the stems! The new growth seems not so red though, maybe my light is not strong enough.

Day 4:

Currently, it is day 4 of growing it. I dose basic fertilizers like Tropica Premium, Seachem Potassium (weekly) and also Seachem Root Tabs (once every few months). I think the plant is adapting to the new environment, I did notice a bit of melting going on.



New Ludwigia sp. Mini ‘Super Red’ Live Aquarium Freshwater Plants Rare Repens Rubin


Mainam Ludwigia Repens Super Red Freshwater Plants Bundle Tropical Aquatic Plant Decorations

Deviated Septum Natural Treatment and Remedies

Deviated Septum refers to the condition where the nasal septum (the bone and cartilage that divide the nasal cavity of the nose in half) is slanted or tilted to one side. The symptoms are typically nasal congestion or stuffiness in one side of the nose. Mild deviated septum is actually very common, 80% of people have it. Moderate to severe deviated septum may lead to nasal problems.

Deviated septum can be typically diagnosed through an X-ray or by nasal endoscopy. Currently, the main treatment for deviated septum is septoplasty, which is a surgical procedure. Due to the surgery involved, quite many people with deviated septum are not keen to undergo the procedure unless it is really serious.

Deviated septum is not a major illness, but the symptoms (of nose congestion) can be very annoying, and also may lead to related problems like sinus infections.

In my personal experience, the deviated septum itself is not the main cause of nose blockage. After all, air molecules are tiny, no matter how narrow is the nose passage, definitely air can pass through it. It is the associated problems of nasal turbinate swelling, and also other nose tissue (such as polyps) swelling and blocking the nose passage that causes the main problem of nasal blockage.

I have compiled a list of natural treatments and remedies that I have personally tried and found to relieve the symptoms of deviated septum. Hope it helps, and if you have other tips, you are welcome to leave a comment below.


Medical Disclaimer: This content is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding deviated septum or other medical conditions.


1) Nose Unblocking Exercises

I have previously blogged about this on Amazing method to unblock stuffy nose. This should be the first method you try since it is totally free and does not require any special equipment.

Basically, pinch your nose and sway, until you are almost out of breath, then breath in through your nose. This has scientific basis, by allowing carbon dioxide to build up and naturally clear your nose by constricting the blood vessels in your nose.

Another method is 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.

2) Nasal Sinus Rinse or Spray

Due to deviated septum, there is a high chance that mucus / dust particles can get “stuck” on the side of the nose that is narrower. Without help, it can be stuck there for a long time and lead to sinus infections, nose blockage, or allergic reactions.

One way to loosen the mucus and wash away the dirt particles is via Sinus Rinse. This is actually a modern version of Neti Pots, which is an ancient Indian Ayurvedic treatment. The classic brand for Sinus Rinse is NeilMed, which is very convenient with pre-packed saline salts for the sinus rinse. (Rinsing with pure water is not recommended as it will be painful. Adding saline salts will make the rinse more comfortable as it has the same osmotic pressure as the human body.)


NeilMed Sinus Rinse – A Complete Sinus Nasal Rinse Kit

A related method to sinus rinse is sinus spray. It is a low-volume method of spraying salt water into the nose. The advantages is that it is more convenient to perform (no need to be near water source or sink). The disadvantage is that it may not be as effective as the high-volume sinus rinse in terms of dislodging particles in the nose.


Stérimar Nasal Hygiene Set of 2x100ml

3) Vicks Inhaler

Vicks inhaler is a menthol-based scented stick, that has the effect of creating a “cooling” effect in the nose, hence immediately creating a sensation of the nose being unblocked. It also has mild decongesting properties. I find that it does reduce the symptoms of nose block due to deviated septum.


Vicks Vapoinhaler Portable Nasal Inhaler, 2 Count – Non-Medicated Vapors to Breathe Easy

The above 3 methods are considered non-medical in nature. Basically, safe to try as long as you follow the instructions in the labels.

4) Decongestants / Anti-histamines

When the nasal blockage is serious, one may try decongestants, which can typically be found in pharmacies without a doctor’s prescription. An example is pseudoephedrine, which can be found in medications like Robitussin, or Clarityn-D.

Anti-histamines can also help to reduce nasal turbinate swelling due to allergy. (Nasal turbinate swelling, also known as nasal turbinate hypertrophy, makes deviated septum worse by making the already narrow nasal passage even more congested.) Clarityn-D also contains the anti-histamine loratadine.


Not Recommended

It is usually not recommended to use Afrin nasal sprays or similar products. It is well known that it can lead to “rebound effect”, meaning that your problem becomes worse when stopping the spray.


The above are just personal natural remedies that I have tried, and found effective in combating deviated septum symptoms. Hope it helps!

Simple Powerpoint Templates White Background

I am a huge fan of simple, minimalistic Powerpoint templates with white background.

Why white background: Basically it is more convenient for printing (save ink), as well as it looks more elegant and professional.

However, most Powerpoint templates are too “flashy” or “colorful”.

On the other hand, the most basic template (just pure white background) is too dull and boring.

Simple Elegant Powerpoint templates

Actually the official Microsoft website has quite a few nice templates. The problem is that less than 5% of them satisfy the criteria of being simple, elegant, and white background.

Two that I found are:

  1. Echo design template
  2. Eclipse design template

If you know other good Powerpoint templates, please share in the comments below!

Diary of a PhD Taxi Driver: True Stories From Singapore’s Most Educated Cabdriver

I recall that this was very big news around 10 years ago. Basically, the author Dr. Cai Mingjie was a research scientist with a PhD from Stanford, specializing in Life Sciences (biochemistry and cell biology). However, he was fired/retrenched at the height of his career, for reasons that were largely unknown. He did not manage to find a job initially and became a taxi driver in November 2008, which he persisted for around six months. (He managed to find another job, though non-academic, subsequently.)

He started a blog called “A Singapore Taxi Driver’s Diary” (now deactivated), which became hugely popular. Subsequently, he published his blog as a book which is featured below.

For a free preview of his stories, one can actually click on the Amazon book preview to read a couple of the short stories. The stories are quite insightful, and motivational in a way. Taxi drivers have a unique perspective since they are able to observe all strata of society on a daily basis.

The free preview on Amazon has the following stories:

  • Day One (first day of working as taxi driver)
  • Broken Barrier and Two Unforgettable Customers
  • Preface & Epilogue (which describes the interesting background of the author)


Diary of a Taxi Driver: True Stories From Singapore’s Most Educated Cabdriver

Overall, the author deserves deep respect for being 能屈能伸, being able to take temporary setbacks; able to bow and rise at will. After all, being a taxi driver is a honest job.


I think the above book and news represented the start of the “bursting of the bubble” of Life Sciences, at least in Singapore. (If a life science researcher with Stanford PhD has problem finding jobs, how about those with lesser qualifications?) For those who recall, life sciences was hugely popular as a major around 10-20 years ago (2000-2010). Many JC students, including many of my classmates/acquaintances would choose it as their major in University. The life sciences department was one of the largest compared to other sciences like Physics or Chemistry. It turned out that the job opportunities in Life Sciences was not that plenty, and many would end up in careers totally unrelated to Life Sciences / biology.


Read also:

iMovie Transition Glitch

iMovie “Corrupted” Frames between two video clips

iMovie is a great free movie editor for Mac. However, an annoying bug is that when two video clips are put together, there can often be “corrupted” frames, glitch, or even choppy video between the two clips.

Simple solution to iMovie Transition Glitch

There are some complicated solutions online, such as re-importing the video clips in certain formats.

However, a simple solution that I tried and tested to work in most cases is to try trimming off a few seconds from the start of the affected video clip. Or even adding a transition effect where the problem arises may work.

To explain more precisely, suppose the problem arises in between A -> B, where A and B are video clips. Then, you can try trimming off a few seconds off the start of video clip B, or adding a transition effect between A and B. (If there is already a transition from A -> B, try removing it!)

Another solution to iMovie Transition Bug

Another solution that I tried and works in some cases, is to export the movie via File -> Share in Best (ProRes) Quality, with Better Quality Compress.

Best (ProRes) Quality and Better Quality Compression may solve your iMovie glitching bugs.

Other solutions to iMovie Bugs between Video transitions

If you have other solutions that you have seen or tried out, please share it in the comments below!

Eheim Air Pump 200 Review

Recently upgraded my air pump to the Eheim Air Pump 200, with dual output. My previous air pump was not strong enough to power 2 sponge filters simultaneously.

This Eheim Air Pump is very strong. In fact, it is almost too strong, I had to lower to the lowest setting for my 2 gallon nano tank. For the 5 gallon tank, I select the medium setting, and angle the output towards the wall. The sponge filter output was made to be above the water level (there is less turbulence this way).

Overall, this air pump is very good and quiet. Do expect some noise though, it is not totally silent. I would say it has the same noise level as a fan, which is totally acceptable. Also, I find that the 2 adjustable valves are not totally independent, when I adjust one valve it will affect the other output as well.

Review: The Eheim Air Pump is a highly recommended air pump for fish keepers with 2 aquariums.

The Eheim 200 Air Pump is also labelled as Eheim PHL207184. There is a more powerful Eheim 400 (twice the output), but based on my review most aquariums under 50 gallons should not require such a powerful pump (maybe 50 gallons and above may need it).

Eheim PHL207184, 4.00 x 6.00 x 4.00 inches, Black

Interesting Linear Algebra Theorems

Diagonalizable & Minimal Polynomial

A matrix or linear map is diagonalizable over the field F if and only if its minimal polynomial is a product of distinct linear factors over F.

Characteristic Polynomial

Let A be an n\times n matrix. The characteristic polynomial of A, denoted by p_A(t), is the polynomial defined by \displaystyle p_A(t)=\det(tI-A).

Cayley-Hamilton Theorem

Every square matrix over a commutative ring satisfies its own characteristic equation:

If A is an n\times n matrix, p(A)=0 where p(\lambda)=\det(\lambda I_n-A).

Stray Feeding Drive May 2020 (SoSD)

Official URL: https://petguru.com.sg/2020/04/20/stray-feeding-drive-2020/

There are indeed more stray dogs than you imagine in Singapore. With the Trap-Neuter-Release-Manage (TNRM) Programme, we aim to reduce the number of strays out there over time. SOSD works closely with stray feeders in different parts of Singapore, in order to trap the dogs, especially the feral ones. Very often, these dogs have learnt to trust their feeders, and catching them would only be possible with the help and cooperation of the feeders who feed them daily.

Amidst the fight against COVID-19, we hope to extend a helping hand to our thankless stray feeders. 365 days a year, the stray feeders painstakingly prepare the daily meals for the stray doggies that they feed, before making their rounds around industrial areas, construction sites or forested areas to deliver food straight to the doggies’ bellies.

If you’ve been wondering how you can chip in during this difficult period, why not make a contribution to ease the pockets of the feeders?

For $98, you can purchase 1 large bag of dog kibbles, to feed 1 stray dog for 40 days.

Simply place your order below, and make payment via PayPal. Orders will close at 2359hrs on 31 May 2020, Sunday. When the donation drive ends, SOSD will coordinate the collection directly with the stray feeders at our supplier’s warehouse.

Please note that tax deduction is not applicable.

Read more at: https://petguru.com.sg/2020/04/20/stray-feeding-drive-2020/

WordPress Twenty Ten Theme Replacement

WordPress Twenty Ten Theme Retired

The WordPress Twenty Ten Theme was my favorite for a long time. However, it is now retired, meaning that it is no longer updated or supported by WordPress. Hence, it is recommended to switch to a newer theme.

WordPress Theme similar to Twenty Ten

I find that the Twenty Sixteen theme is quite similar to Twenty Ten in terms of layout. It has the signature top header as well as right sidebar classic layout. After much consideration and testing out other themes, I decided to switch to the Twenty Sixteen theme!

It does take some time to get used to the theme. The theme has a very clean and minimalistic look. In fact, the only downside I would say is that the 2016 WordPress theme is a bit too minimalistic, there is not enough colors other than white.

Loki the dog euthanized

Recently, there is a sad news in Singapore about the euthanasia of a perfectly healthy dog called Loki, for purported “aggression”.

To read more, just google the following keywords:

  • loki dog
  • loki dog singapore
  • loki dog euthanasia
  • loki dog put to sleep
  • #justiceforloki hashtag on Twitter

You can also find more information on the Exclusively Mongrels Limited Facebook page. Exclusively Mongrels was the organization that Loki came from (Loki was a stray dog). One of the volunteers at Exclusively Mongrels was brave to speak out about Loki’s euthanasia, but unfortunately he is now being accused by the owners for “doxxing”.

Do sign this petition on “More stringent regulations for putting dogs to sleep in Singapore“!

#JusticeForLoki: Help Exclusively Mongrels Raise Funds for Loki

Mega Database of JC Prelim Papers

Just to reblog this post on where to find “A Level Free Exam Papers”. The link below is literally the biggest collection of JC Prelim ‘A’ level papers I have ever seen. Both H1, H2 and even the occasional H3 exam paper can be found, for multiple subjects. Do download while it is still available!

Singapore Maths Tuition

Link:  http://tinyurl.com/holygrailrepo2

This weirdly titled Google Drive (“Electric Boogaloo”) contains a mega-database of JC Prelim papers for most if not all subjects, even esoteric subjects like “Theatre Studies and Drama”. Exam papers ranges from H1 to H3, and from the years 2008 to 2019.

Do download in advance if you need the material, from experience such Google Drives tend to “disappear” from time to time.


We have included the above link in the Free Exam Papers / Free Test Papers page, containing other large sources of Free Exam Papers.

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Cool Math Games

Some games are fun but not educational.

On the other hand, some games are educational but not fun!

This very popular website Cool Math Games is a combination of fun and educational!

Benefit of Cool Math Games

  • Their games are all browser-based, there is no need to download anything. It can be played on your Internet Explorer or Chrome browser.
  • They have a wide range of different games, ranging from Numbers, Logic, Trivia, and Strategy.
  • Their games are kid-friendly and educational.

Cool Math Games Example

This games “Swap Sums” is suitable for lower elementary school kids (age 5-10). It starts off easy, but the later stages are actually quite challenging. For example, the stage below actually requires some thinking to get it right.

This is the Swap Sums game from Cool Math Games.

Cool Math Games Review

Children naturally love to play games. When I was a child, my favorite activity was to play computer games. Hours can just fly by when playing games. When playing games that are educational at the same time, it can hugely benefit a child in terms of increasing his/her interest in the subject.

Hence, parents are encouraged to let their child play educational games, such as Cool Math Games, to relax as well as to learn. Most children learn better when the content is fun and engaging.

Fake Micro SD Card!

Recently, bought a suspected fake SanDisk Micro SD Card on Qoo10 (Singapore online retailer).

Apparently, fake Micro SD cards (used for cameras as storage) are very common, even on Amazon and eBay. A popular estimate is that 1/3 of all micro SD cards on the market are fake!

The one I bought was a 16 GB SanDisk microSD card. Basically, according to this website, “The 16GB SanDisk branded item is a fake. There is no 16GB micro SD product in the SanDisk product line — it is a fake.

What made me quite angry is that not only it is fake, it couldn’t work as well! (If it were fake but worked well, I could close one eye…) Both my Xiaomi Camera and also the card reader I got could not even detect it. The card reader with the fake microSD card could not be detected by either PC or Mac.

I think the main visible difference between the real SanDisk Micro SD and the fake is that:

  • The real microSD card has a imprinted rectangle box on its flip side (see the 1st video below for more details, the real one is on the right).
  • If you shine a light on the front face, it should say “Made in China” for the real Sandisk microSD card (see the 2nd video below).

Other differences include:

  • The fake microSD card has lower speed and volume (for example it could be rated 64GB but only has 2GB space!)
  • Lower printing quality on the fake microSD card

The authorities should really crack down on these fake SD cards. It is getting harder and harder to distinguish between the real and the fakes, some of the fakes replicate 99% of the real product up to the design of the packaging.

中学快捷华文O-Level 试卷二答题注意事项 (Tips for O-level Chinese Paper 2 answering techniques)

Chinese Tuition Singapore

综合填空

综合填空中需要从4 个选项中选取答案正确的那一项。选择正确答案时,需要考虑以下因素:

1,词义: 词的意思是不是符合题目。词义要通顺。(这是最基本的)

2,词性:判断要选的词语是褒义,贬义还是中性词。该填入名词,动词,形容词还是副词。

3,搭配:注意一些词语的常见搭配和固定搭配。比如:硕果+累累 或者累累硕果,严峻的考验,顽强的毅力等。还有一些词语是有特定范围的,比如,毛毛虫蜕变成蝴蝶。

4,若是四个选项中,有一个或几个词语都不知道其意思,那么先看自己认识的那个选项,如果那个选项是对的,意思,搭配都通顺,那么就大胆去选。如果自己认识的词语不符合要求,那么直接排除,在剩余的选项中去选择,只要有选项被排除掉,在剩下的选项里进行选择也会提高正确率。

阅读理解 (MCQ)

1,一定要去原文中找答案!一定要去原文中找答案!一定要去原文中找答案!(重要的事情说三遍!)按照题目中的关键词去原文中找答案!为了确保自己真正是从原文中找到的答案,可以在原文中把答案画出来。一定不要自己猜测,或者自己想当然地认为。在去原文中找答案时,一定要仔细,如果改变了其中几个词语,没有影响原文的意思,那么就可以接受,若是,改变了原文的意思,那么一定要小心,不要上当。比如,原文中用的是“可能”,“部分”等词语,选项中却用了“一定”,“全部”,这就是改变了原文的意思。

2,记住新闻类关于这篇文章的主要内容/主要信息,一定去第一段(导语)部分找。

3,遇到很难懂的文章也不要怕,只要记住:去原文中找答案!再难的文章也不怕。

4,道理类,这篇文章说明了一个什么道理/作者想通过这篇文章传达什么样的想法,此类题目的答案通常在文中的结尾(最后一段或最后一句),一定要选符合意思的那个选项。

5,答题时要小心,一些题目要求选择不对的那一项,或者不包括除了,出现了这些词语要格外慎重。

6,当四个选项中,有三个选项是文中出现的具体措施,具体做法等时,要看剩下的那个一选项是不是能够概括其他的三个。也有可能三个当中只有一个符合题目给出的特定条件。

理解问答(reading comprehension)

1,通常前几题的答案可以从原文中找到,那么一定要把全部答案找对。可以根据分值去判断答案到底有几个要点,比如,4分的题目可能有4点或者2点。

2,解释划线句子的意思,请参考:

阅读理解中解释划线句子的意思 Tips for Rephrasing in Reading Comprehension

3,人物描写手法,修辞手法,说明方法,论证方法这些作用以及答题模式,请参考:

人物描写手法:

 

 

 

 

 

 

肖像描写

通过肖像描写能看出人物的内心世界,展现人物的性格,反映出人的喜好、身份、生活态度等。

例:

1.她个子高高,面容清秀,细细弯弯的眼睛满是笑意。

这段肖像描写,表现了她十分亲切,待人友善的性格特点。

2.小男孩圆圆的脸,弯弯的眉,一双机灵的大眼睛。他身穿发黄的白色衣服,脚上是一双破旧球鞋。

这段肖像描写表现出小男孩可爱又聪明的特点。而且从他穿的“发黄的白色衣服和破旧球鞋”可以看出,小男孩的家庭条件不是很好/家里不是很有钱。

 

 

 

 

 行动描写

体现人物的身份、地位 ;反映人物心理活动的进程;表现人物的性格特征;推动情节的发展。

例:

1.我几次伸手要去按门铃,有几次把手缩了回来。

从这句话中“我”伸手又把手缩回来的动作可以看出“我”当时十分为难,又犹豫的心理。

2.说完,他跳下车,三步并作两步地奔进屋里。

这句话对“他”十分兴奋又激动想要快点xxxxx的心情。

 

 

 

 语言描写

能够表现人物的思想感情,反映人物的心理活动。

例:

老师,能不能,能不能……”把“能不能”呢喃了好几遍,小男孩才很难为情地抬起那一直比脖子还低的头,小声地说:“能不能给我的作文加上一分?”

这段话中,通过描写小男孩说的话,表现出小男孩内心非常紧张又不好意思,但是又特别希望老师给自己加上一分。

 

 

 

 心理描写

揭示人物的内心世界,表现人物丰富而复杂的思想感情。也可以让文章更生动。

例:

我已经是中学生了,应该又自己的空间。更何况我又不是故意迟回家!

这段对“我”的心理描写,表现出被“爸爸”责备之后,“我”觉得自己没错,非常委屈的心理。

修辞手法:

常见的修辞手法 Figure of Speech in Chinese

说明方法:

常见的说明方法及其作用&答题模式

论证方法:

1)、举例论证:是列举确凿、充分、有代表性的事例证明论点的方法。因为“事实胜于雄辩”,所以举出确凿典型的事实来证明论点,能增强文章的说服力。

答题模式:通过列举xxxx的例子,来论证xxx,增强文章的说服力。

2)、引用论证:是引用具有权威性的言论证明论点的方法。所以这种方法使用得当,有很强的论证力量。分析引证法的作用,应先弄清引用了谁的言论,是为了证明什么,再把握引证法的特殊作用——具有权威性,论证有力。

答题模式:通过引用xxxxx,来说明xxx的道理,使论证更有说服力。

3)、比喻论证: 就是通过形象的比喻来证明论点的方法。这种方法可深入浅出地把道理讲得通俗形象,容易被人接受。

答题模式:通过把xxxx比作xxxxx,使xxx道理更浅显易懂,便于读者理解。

4)、对比论证:是用正反两方面的事实和道理进行鲜明对比,从而证明论点的方法。分析对比论证方法作用,两个方面XX比较,使其对与错更加分明,正确的观点更容易被读者接受。

答题模式:通过把xxx和xxx进行对比,是xxx道理更深刻,更有说服力。

4,文章中的xxx是一个什么样的人/有什么样的性格特点,请举例说明。

这类题目通常4分。一定要记得,在写人物的性格特点时,要写两点。1个性格特点(1分)+举例说明(1分),所以,写出两点才能把全部4分拿到。

5,结合文章内容,说说你对xxxx的理解。

通常这类题目会选取文章中的一句话,首先,要先解释这句话的意思。解释完之后,要去文章中找出和这句话有关系的部分,可能是故事中某个人物的经历,刚好印证了这句话。也有可能是作者的某个观点,证明了这句话是对的。

6,联系实际,谈谈你对xxxx的理解。

这类题目也通常会选取文章中的一句话。首先还是要解释这句话的意思。解释完之后,联系实际要怎么联系呢?可以列举生活中的例子或者现象。举完例子之后,再解释总结这个例子也说明了xxxx的道理。

7,你同意/赞成xxxxx吗?为什么?试联系实际谈一谈。

这类题目通常是5 分。

表明态度:赞成/不赞成,同意/不同意 (1分)

原因:(2分)为什么赞成/不赞成. 原因部分不可以只说一句话就结束,要尽量解释详细。可以从正反两个方面去论说。这样做为什么好,会取得什么样的好效果。不这样做又会有什么样的后果。比如,作者认为“兴趣是最好的老师”,你同意吗?答:我同意。因为若是一个人对某件事情产生兴趣,他就会在这件事情中投入极大的热情和精力,而且会让他去自觉主动的学习,这样,学习的过程对他来说充满了乐趣,兴趣推动着他不断进取,不停吸收新的知识。(正面)若一个人对某件事情没有兴趣,那么做这件事情对他来说就是一种痛苦和煎熬。即使让全世界最好的老师来教他,他也不会有想去好好学习和钻研的欲望,再多的苦心都是徒然。(反面)

举例子:(2分)可以举生活中的例子,或者名人事例。举的例子一定要符合题意。若是自己不确定要举哪种例子,那就仿照作者在文章中举的例子,写一个相近的。若是想不到生活中的例子,那就只能编故事了。一定不可以空着!通常理解问答的最后一题,即使题目没有明说要举例子,自己也要举出例子来说明。

通常理解问答的最后一题,分数最多,而且最容易得分。在考试时间不够用的情况下,建议先把最后一题做完。

在时间分配上,不建议在第一题(综合填空)花费太多的时间。因为第一题是选择题,每题只有1分,所以当遇到自己不确定的题目时,先选一个答案,做上标记,等到最后试卷全部做完,有剩余时间时再回去思考。一定不要在第一题耽误太多时间。

MCQ每题2分,所以做的时候,尽量细心,认真,一次把答案找出来。

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Ex-Actress Evelyn Tan Supports Her Kids Pursuing Entertainment Careers Without A Degree

Quite interesting, and makes a bit of sense too. In this new age where almost everyone has a degree, not having a degree may in fact stand out (for unique career paths)! It carries risk though, naturally.

Source: https://mustsharenews.com/evelyn-tan-kids/

Son planned his career as streamer

When her son Jairus, 12, said he wanted to be a Twitch streamer, Evelyn was confused. According to Toggle, she did not know about the online streaming platform for gamers.

She called him a “thinker” — he had told her that if he started his career now, it would be established enough to be profitable by the time he turns 21.

Her son then pointed out that a degree would be irrelevant to his career, which Evelyn said was fine.

Evelyn Tan majored in Math in NUS

Not many people know this, but actress Evelyn Tan once majored in Math in NUS, and graduated successfully. “Upon graduating from the National University of Singapore with a degree in mathematics, Tan joined the fifth edition of Mediacorp’s Star Search in 1997.”

Read more at: https://mothership.sg/2019/11/evelyn-tan-interview/


See also (famous actors/ newscasters/ singers who majored in Math):

School holiday activities for children stuck at home

Due to the circuit-breaker, most children are unfortunately stuck at home during their school holidays. Other than playing computer games, this article suggests other educational and fun activities for children and their parents: School holiday fun at home: Kids can go online to stargaze, study about animals, do science experiments.

The live stargazing activity of Science Centre sounds quite fun: https://www.facebook.com/183389296588/videos/2534433140205259/

Most of the activities are open to children outside Singapore as well!

Motivational: Take it one thing at a time

Source: https://medium.com/mind-cafe/four-habits-of-discipline-my-seal-dad-taught-me-7ed9b13987df

Just saw this article on Medium. Quite motivational and applicable to students and even working adults. There are 4 tips on the original website. We just quote one of the tips here. The Chinese equivalent, would be 千里之行,始于足下, or “A journey of a thousand miles begins with a single step”.


Enduring Work Ethic Stems From The Moment

I had an interesting conversation with him about Hell Week (some US SEAL army training week) a few years back.

For those who don’t know — Hell Week is ridiculous. You wake up on a Sunday to gunfire. You then work out until Friday with no sleep. Hell Week is the bottleneck that breaks a lot of talented people. It’s where the top 20% are whittled down to the top 5%.

I remember him saying, “Tuesday morning was the worst.”

It was a bizarre response. Tuesday? Wouldn’t Thursday be the worst? Or Friday morning? Then he explained and it made total sense.

You wake up on a Sunday morning at ~2 AM to gunfire. You run around getting yelled at. You are doing pushups, carrying logs, rolling in the sand. This continues all day, then into the night.

As people are sleeping in their warm beds, you continue exercising, shivering, and getting shouted at.

Monday morning comes. The drills repeat from sun up to sun down with non-stop exercise and physical torture. Then, all through the night, you do it again.

Then, Tuesday morning rolls around. You’ve gone more than two full nights without sleep. You’ve endured intense stress, cold water, and difficult exertion the whole time. By Tuesday morning, you’re more tired than you’ve ever been in your entire life.

That’s when you start to feel sorry for yourself.

“Oh man, it’s only Tuesday. How am I going to get through all of this?”

“If I’m this tired already…and I’m not even halfway through…”

The people that start thinking like this are the ones that quit.

The people who succeed — only look a few minutes in front of them. They don’t worry about Thursday or Friday. They are only focused on each individual exercise. They get through it one thing at a time.

You can apply this to many aspects of your life.

If you are studying for a massive test, take it one page at a time. Working on a huge presentation, one slide at a time.

For example, I swam in college. Our training was very grueling, 5 to 6 miles of swimming a day. Sometimes the coach would put a set on the board that made me think, “You’ve got to be f#$king kidding me. I’m going to die.” I just took it one lap at a time and got through it.

Lower your vision and piecemeal those big hurdles. It reduces the perceived mental weight of the tasks. Take it one thing at a time.

Rhodeus bitterling fish 鳑鲏鱼

I have never seen this fish before in Singapore. In China, it seems common. It is called “Pang Pi” fish, or Rhodeus /bitterling fish. Although it is not very colorful, it is quite unique due to its relationship to the clam.

As you can see from the video, it likes to hang around the clam/mussel, and it will even lay its eggs inside. Apparently, the clam also deposits its eggs on the “Pang Pi” fish.

Clams are hard to keep, and can be quite tricky for beginners. It is hard to tell if the clam has died or not. (Even an alive clam does not move much. You can see how it moves in the video.) Once the clam has died, it will start decomposing and producing toxins which may harm the entire tank. Also, it is quite common for clams to have parasites and worms in them.

The Spiritual & Humanitarian Aspects Of The Gospel – Homily by Archbishop William Goh

For the complete Mass recording go to: https://youtu.be/IzXhGM2QB8Q

The Church must never forget the priority of providing spiritual food to the People of God. This is critical and can never be replaced by mere humanitarian services. This was precisely what the early Christians did. They did not simply do humanitarian works when they cared for the poor and the widows. Their goal was ultimately spiritual. The works of mercy that they did were in continuation of Jesus’ works of mercy. They were meant to reveal the Father’s mercy and love for them. The gospel cannot be proclaimed without the works of charity, otherwise, it will merely be words. People need to see Christ and encounter His love and mercy concretely in their lives.

NUS High E-Open House

https://youtu.be/Ho5L5fAeNjU

The (promotional) video for NUS high open house is out! Parents and students who are interested to apply for NUS high are encouraged to watch it.

The actual open house will be on 15 May.

Singapore Maths Tuition

URL: https://www.nushigh.edu.sg/admissions/open-house

NUS High will be holding its E-Open House on 15th May. Do check it out!

NUS High is famous for its strong Math and Science curriculum. Many of their students are very strong in Math Olympiad and other Scientific topics.

E-Open House
15th May (Short Presentation and Q&A session with School Leaders, Alumni and Parents)

  • 1st Session: 9:00 – 11:00 am
  • 2nd Session: 2:00 – 4:00 pm

E-Engagement Sessions

  • 1st Session: 19th May (Tue), 4:00 – 5:00 pm
  • 2nd Session: 23rd May (Sat), 9:30 – 10:30 am
  • 3rd Session: 23rd May (Sat), 2:30 – 3:30 pm
  • 4th Session: 27th May (Wed), 4:00 – 5:00 pm

For further clarifications, please email: newton@highsch.nus.edu.sg


Also check out:


Update (provided by one of my Facebook readers):

NUS High School has put out its school presentation as part of its E-Open House on…

View original post 65 more words

How to free up space on Gmail

4 Steps to clear space in Gmail

Although Gmail has 15 GB of space, it can run out of space quite fast, especially nowadays many emails contain attachments that can be quite large.

To free up space on Gmail, I usually do the following 4 steps:

1) Search “size:100k older:2018” on Gmail

The above searches for files 100 kilobytes or larger, dated 2018 or earlier.

You can modify your search accordingly, for example “size:1M older:2017” searches for files larger than 1 megabyte, older than 2017.

2) Search “from:facebook.com”

The above searches for all email sent from email address ending with “facebook.com”. This can be quite effective, since many small emails typically end up being larger than 1 single big email.

You can modify your search accordingly, for example “from:twitter.com”, etc.

3) Delete unwanted emails (found using methods above), and clear Trash

Clearing trash is important (otherwise the deleted files will still take up space). Messages that have been in Trash more than 30 days will be automatically deleted though.

Double check before you delete, since once deleted it is not possible to recover the emails.

4) Refresh your browser, and see that you have more space!

Typically, by using the above steps, I can delete up to 1o0 MB of email.

 

Toy Poodle Pictures

Toy Poodle Pics and Videos

Just to share some pictures and videos of Charlie the toy poodle. Actually, we are unsure of whether he is a pure toy poodle or not, some people commented that he does not look like one! Charlie is 6 months old now.

Poodle apparently descended from a water dog in Germany. Charlie the poodle loves to play water! Also, poodle is commonly said to be the 2nd most intelligent breed, after Border Collie.

How to convert w/w% weight concentration to ppm

In this post, we describe how to convert w/w% (weight concentration of a solution) to ppm (parts per million, or mg/l), with applications to liquid fertilizers.

This method is an approximation for dilute solutions.

We will focus on converting 0.8 w/w% to ppm, with 2ml of fertilizer in a 5 gallon container. This is based on Tropica fertilizer Potassium concentration. We will then verify it with the Rotala Butterfly calculator (answer is 0.845 ppm).

1) 0.8 w/w% = 8g per 1000ml

Here we have made the assumption that 1000ml of solution weighs 1000mg, which is valid for dilute solutions.

2) This is equivalent to: 0.016g per 2ml (in the fertilizer).

3) Now after pouring the fertilizer into the 5 gallon container, the concentration is 16mg per 5 gal = 16mg per 18.9271 liters.

Here we have made the approximation that the amount of fertilizer (2ml) is negligible compared to the volume of the container (5 gal).

4) This is equivalent to 0.845 mg per l or 0.845 ppm as calculated by the Rotala Butterfly calculator!

Rotala Butterfly Calculator Formula

Let a be the w/w% concentration.

Let b be the amount of fertilizer to use (in ml).

Then,

ppm = (10ab)/18.9271

In the example above,

a=0.8, b=2, so

ppm = (16)/18.9271=0.845

Mango Sticky Rice

Recommended Mango Sticky Rice Recipe!

Cooking For Fun

Finally I made one of my favorite dessert: mango sticky rice.

Ingredients:

Sticky rice 1 cup

coconut milk 2/3 cup

sugar 1/3 cup

salt 1/2 tsp

1, Wash sticky rice in water till water is completely clear. Soak them overnight.

2, Drain them and steam over hot water for about 30 mins.

3, When the sticky rice is about to be done, start to make the sauce.

4, Add coconut milk, sugar and salt into a pot. Turn to low heat, keep stirring till sugar is dissolved.

5, Put sticky rice into a big bowl, pour the sauce in. Stir slightly to mix them. Then cover the bowl and let it rest for about 20 mins. Rice will absorb the coconut sauce and flavor.

Fot topping:

1/2 cup coconut milk

1/4 tsp salt

1 tsp rice flour

1 tbsp water.

Heat a pot, Add in coconut milk and salt. Stir…

View original post 35 more words

NUS High E-Open House

URL: https://www.nushigh.edu.sg/admissions/open-house

NUS High will be holding its E-Open House on 15th May. Do check it out!

NUS High is famous for its strong Math and Science curriculum. Many of their students are very strong in Math Olympiad and other Scientific topics.

E-Open House
15th May (Short Presentation and Q&A session with School Leaders, Alumni and Parents)

  • 1st Session: 9:00 – 11:00 am
  • 2nd Session: 2:00 – 4:00 pm

E-Engagement Sessions

  • 1st Session: 19th May (Tue), 4:00 – 5:00 pm
  • 2nd Session: 23rd May (Sat), 9:30 – 10:30 am
  • 3rd Session: 23rd May (Sat), 2:30 – 3:30 pm
  • 4th Session: 27th May (Wed), 4:00 – 5:00 pm

For further clarifications, please email: newton@highsch.nus.edu.sg


Also check out:


Update (provided by one of my Facebook readers):

NUS High School has put out its school presentation as part of its E-Open House on 15 May 2020, and its related e-engagement events for parents and interested P6 students. The content is well planned to clarify common questions from parents and potential students.

YouTube link to the school presentation (about 30mins long):

There is also a Telegram group to receive information on NUSH Admissions for DSA 2020 (for the Class of 2026) :-
(please subscribe for timely updates !) https://t.me/nushighschool

Slow and Steady Snail (Homeschool Math Favorite Challenging Puzzles)

This is a favorite type of homeschool math challenging puzzle — The Snail question.

Question: An aquarium is 47 cm deep. A snail starts at the bottom of the aquarium. Each day, during the daytime the snail climbs up 8 cm, and during the nighttime the snail slides down 3 cm. How many days will it take for the snail to climb out of the aquarium?


This is part of a series on Homeschool Math Challenging Puzzles, suitable for Grades 2-4. (Of course, students of other grades are also welcome to try them out.) The questions are suitable for:

  • Homeschooling for gifted kids
  • Preparation for GEP (Gifted Education Programme) screening and selection tests
  • Preparation for Math Olympiad
  • Puzzles for kids interested in math but find school work too easy.

Solution:

A tempting answer would be 10 days. This is a trick! Those who get the answer “10 days” reason like this: each day the snail moves a net distance of 8-3=5 cm.

Hence, 47/5=9 R 2.

At the end of the 9th day, the snail moved 45 cm. Thus, rounding up will give 10 days as the answer. However, there is a tricky part to the question!

The correct answer is 9 days.

We can do a list:

Day 1 — 5 cm

Day 2 — 10 cm

Day 3 — 15 cm

Day 8 — 40 cm

Day 9 day time — 40 +8 = 48cm > 47 cm !!!

The snail is already out of the aquarium on Day 9!

Nano Fish Species [35 fish/aquatic creatures below 9 cm!]

Fish Max Length (cm)
Dwarf gourami 8.8
Black skirt tetra 7.5
Betta splendens 7
Honey gourami 7
Amano shrimp 6
Guppy (female) 6
Panda corydoras 5.5
Otocinclus 5.5
Cardinal tetra 5
Harlequin rasbora 5
Serpae tetra 5
Rummy-nose tetra 5
Zebra danio 5
Mexican dwarf crayfish 5
Cherry barb 5
Endler’s livebearer (female) 4.5
Cherry Shrimp (Neocaridina davidi) 4
White Cloud minnow 4
Sparkling gourami 4
Hara jerdoni 4
Neon tetra 3.5
Guppy (male) 3.5
Green neon tetra 3.5
Clown killi 3.5
Pea pufferfish 3.5
Assassin snail 3.5
Dwarf corydoras 3.5
Pygmy corydoras 3.2
Lambchop rasbora 3
Pseudomugil gertrudae 3
Horned Nerite Snail 2.5
Endler’s livebearer (male) 2.5
Celestial pearl danio 2.5
Chili rasbora 2
Phoenix rasbora 2

Credits: All images are from Wikipedia (and/or my personal collection of fish), unless otherwise specified.

Fish Math

How to ensure a pair of male-female for fish & Shrimp

Given N fishes/shrimp, what is the probabillity of having at least 1 male-female pair?

Probability = 1 – (Prob. Of all Male)- (Prob. Of all Female)

If you have 4 fishes, Probability of having a breeding pair = 87.50%

If you have 5 fishes, Probability of having a breeding pair = 93.75%

If you have 6 fishes, Probability of having a breeding pair = 96.88%

If you have 7 fishes, Probability of having a breeding pair = 98.44%

If you have 8 fishes, Probability of having a breeding pair = 99.22%

Canon PIXMA G5020 (G5070) Review

Canon Most Ink Efficient Printer

Just bought this printer (Canon PIXMA G5020, which is listed in Singapore as Canon PIXMA G5070). It is ideal for home use for students and working professionals.

Its advantages include:

  • Very efficient “ink tank” system. The ink refill system is by bottles of pure ink liquid instead of cartridges.
  • Design for high volume printing at low running cost
  • Compact size and dimensions (Approx. 403 x 369 x 166 mm for factory configuration,  Approx. 403 x 695 x 356 mm when Output/ADF trays extended)
  • Dual paper loading (you can load paper on the rear tray as well as the front tray). If you retract the rear tray, the printer becomes even more compact (just 16.6cm tall).
  • High speed (for inkjet): ISO standard print speed (A4): up to 13.0ipm black / 6.8 ipm colour
  • Supports wireless connection to computer as well as smart phone.
  • Automatic Duplex


Canon PIXMA G5020 Wireless MegaTank Single Function SuperTank Printer | Mobile & Auto 2-Sided Printing

Overall, this is the ideal printer for work from home, as well as homeschool purposes. It is even more ideal for those who don’t want additional features such as scanner and fax. By not having those features (which you may not need), it has a very economical affordable cost. Especially when you factor in the long term savings from cheap and long-lasting ink refills.

If you do want copier, fax and scanning features, then you can consider the Canon PIXMA G7020 instead, which is basically the Canon G5020 with the additional features.


Canon PIXMA G7020 Wireless All-in-One Supertank (Megatank) Printer, Copier, Scan, Fax and ADF with Mobile Printing, Black

How to speed up R code in RStudio

I just found out by trial and error that the suppressing of print statements in RStudio greatly speeds up the R code.

In my case, code that was originally estimated to take around 40 hours to run,  just ran in under an hour after I suppressed all the print statements in the for loops.

This is supported by evidence in other forums, for example in StackOverflow: R: Does the use of the print function inside a for loop slow down R?

Basically, if your code prints too much output to the console, it will slow down RStudio and your R code as well. It may be due to all the output clogging up the memory in RStudio. R is known to be “single thread” so it can only use 1 CPU at a time, even if your computer has multiple cores.

Hence, the tips are to:

  • Reduce the number of print statements in the code manually.
  • Set quiet=TRUE in all scan statements. Basically, the default behavior is that scan() will print a line, saying how many items have been read.

This is especially true with for loops, since the amount of printed output can easily number to the millions, and overwhelm RStudio.

5 Tips on How to Survive Physics in Junior College

5 Tips on How to Survive Physics in Junior College

Many students, during the early stage of their college life, tend to struggle through an entirely new syllabus for physics. Apart from the complexity of the discipline, the problem with physics gets more aggregated when different new teachers teach it, each having their teaching methods. Surviving the ‘torments’ of physics in junior college, especially in an as a highly-ranked country like Singapore, isn’t that easy. However, it’s not impossible, either!

You don’t have to spend any more extra time or money to get into a popular physics tuition center in Singapore. Instead, you can prepare yourself with these five life-saving tips to help you survive the two-year roller coaster ride!

 

  1. A good relationship with your instructors

You need to enhance your bonding skills and treat your physics teachers more as life mentors at this point. The more you value their presence in your life, and maintain a helpful, friendly relationship with them, the better are your chances of you getting their additional assistance like extra classes. This will make it easy for you to understand the problematic theories and get more attention in the class.

  1. The priority is understanding!

The transition from secondary school to junior college is indeed one of the most significant phases students in Singapore academically go through. No wonder why the syllabus for physics looks so exhausting, right? Even if you get poor marks at the beginning, make sure you understand the theoretical maths and laws. Frequently ask questions and request further clarification in the class until you have understood correctly.

A clear understanding is what matters the most! Furthermore, pay more attention to your progress in the maths classes as wells! Physics and maths are closely related to each other so that you will benefit either way. Consider enrolling in a popular maths tuition center in Singapore, if you think you need extra help.

  1. Sign up for physics courses

While your everyday studies will most of your time, try your best to focus on something else outside the monotonous realm of academics.  Make sure you are a lead member of your science or maths club. Extra-curricular activities on physics will come in handy for you to achieve better grades. If you can afford more time, try to enroll in online physics courses on educational platforms. You can also watch physics tutorials online to clear any subtle confusions on the basics.

  1. Seek help from your seniors

No doubt that in junior college, all the students naturally go through a hard time. However, that is not enough to justify that your seniors will have no time at all to lend forward their help to those who are still new to junior college! Therefore, maintain a friendly relationship with all your seniors who are seemingly performing great in physics and maths. Shower them with respect, let them know how they inspire you. They will definitely try to make out some time to help you out!

  1. Get a private tutor!

Additional tuition, especially that too of an as complicated a subject as physics, is instrumental in junior college. Most tutors are high-qualified and are naturally aware that you’re still adjusting to the advanced level of theoretical physics, and they can help make the transition easier for you. Moreover, this can also be a perfect time to productively utilize any leisure available, which is something that most tuition centers or private tutors will focus on teaching you first.

We do understand, junior college physics is very tough, but it’s possible to pull through, especially by following the tips provided above. If you can sincerely abide by them and along with that, just a pinch of persistent merit with two spoons of will and hard work will be enough to score good grades in your physics exams!

StarHub Rebate Registration Form

StarHub Rebate Link

In addition to the apology, StarHub will offer affected customers a one-time 20% rebate on their Home Broadband monthly fee, which is equivalent to six days of free home WiFi service. A dedicated website will be made available for affected customers to register for the rebate. Details will be announced to customers soon.

Note that the deadline is: 26 April 2020!

Sign up at: https://www.starhub.com/broadband-rebate


Share this to your friends and relatives using StarHub! This rebate is typically worth around $10 (20% of $50 broadband subscription). The key thing is that only those who registered above will be given the rebate!


Related posts:

Amount of Potassium in Singapore Water

The official document for Drinking Water Quality analysis can be found on the PUB website.

Note that the above document does not contain any information on potassium (K).

Potassium Content in Singapore tap water

I managed to find another source (dated 2002) on potassium content in NEWater: http://uwatech.com/wp-content/uploads/2015/11/newater-study-report.pdf. In page 16, the potassium levels are stated as:

Range (Potassium): 0.504 to 3.07 mg/L

Mean (Potassium): 1.08 mg/L

Sodium Content in Singapore water

Range (Sodium): 3.16 to 42.1 mg/L

Mean (Sodium): 13.35 mg/L

Potassium in Planted Tanks

For aquarium plants, “potassium content should be at least equal to sodium content or higher.” (http://aquayer.com/index.php?page=kaliy-v-akvariume&lang=en)

Usually, the solution is to dose potassium fertilizers (for example potassium sulphate).


Seachem Flourish Potassium 500ml

In addition, many sources recommend a level of around 20 ppm of Potassium for planted tanks (see for instance this site). That is 20 times the amount found in tap water! Other sources push it further, there are sites that recommend up to 50 ppm of potassium.

Tropica fertilizer composition

Tropica has 2 brands of liquid fertilizer — Specialised Fertilizer and Premium Fertilizer.

The Specialized fertilizer has N+P (nitrogen and phosphates), while the Premium does not. Unfortunately, not much information is available on the exact ingredients, composition, or percentage of each type of nutrient. For example, it is unclear how much potassium the fertilizers have.

I managed to find the exact composition on the UKAPS forum:

Tropica Fertilizer Composition and Ingredients

Nutrient (w/w%) Premium Fertilizer Specialised Fertilizer
Nitrogen 0 1.34
Phosphorus 0 0.1
Potassium 0.8 1.03
Magnesium 0.39 0.39
Sulfur 0.91 0.91
Zinc 0.002 0.002
Molybdenum 0.002 0.002
Boron 0.004 0.004
Iron 0.069 0.069
Copper 0.006 0.006
Fluoride <0.001 <0.001
Chlorine 0.438 0.5
Manganese 0.039 0.039

The Declaration Certificate showing composition of Tropica fertilizers.


 


Tropica Specialised Fertiliser – 300 ml


Tropica Plant Growth Premium Fertiliser,300 ml


Tropica Fertilizer ppm

The composition of ingredients given by Tropica is in w/w% which is weight concentration of a solution. Usually, we want to know the concentration in ppm, or parts per million (equivalently, mg/L).

For that, we can use the Rotala Butterfly calculator. The below information is based on 1 pump (2ml) for a 5 Gallon aquarium.

Your addition of 2 ml (equivalent to 1/4 tsp + 1/8 tsp + 1/32 tsp ) Tropica Plant Growth Premium to your 5gal aquarium adds:

Element ppm/degree
K 0.845
Mg 0.412
S 0.962
Fe 0.073
Mn 0.041
B 0.004
Cu 0.006
Mo 0.002
Zn 0.002
Cl 0.463

It is quite a “light” dose. Considering that the recommended target concentration of K is 10-30 ppm (from Tom Barr). Singapore water only has on average 1 ppm for K (potassium). Hence, the once a week dose of Tropica fertilizer Premium is definitely not enough to hit 10-30 ppm of K.

StarHub Down

Is StarHub down?

The answer is yes! Please see the official news by Today: StarHub customers hit by major fibre service disruption.

It is also reported by Straits Times that, yes, StarHub is down.

StarHub Network Down (Solved)

I stumbled upon the solution to solve the issue of “Starhub Network Down”. Note: This applies if your Starhub Network is slowed down but not completely dead/inaccessible.

Solution: Google DNS

My StarHub internet slowed down to a crawl, it took almost forever to access a simple website like Gmail or Yahoo. Hence, it can be classified as “StarHub Almost Completely Down“.

Upon changing to Google DNS using this official Google guide, to my astonishment the internet sped up to be even faster than before the “StarHub Down” issue.

Speed test of StarHub internet speed (after changing to Google DNS) on the day that StarHub was supposedly down!

I am not exactly sure of the mechanism behind, but changing to Google DNS certainly solved the issue of “StarHub Internet Down” for me. I suspect that due to the StarHub network down issue, most of StarHub remaining working “servers” are overcrowded and overloaded. Hence, if you switch from the StarHub DNS to Google DNS, you are leaving the “crowded server” and that explains the faster speed.

For record, I used the following Google DNS (IPv6):

2001:4860:4860::8888 and  2001:4860:4860::8844.

For safety concerns, it is considered quite safe to trust Google DNS. (Read their details on Wikipedia.) Basically, if you are already using Google products like Gmail, Google search engine, you might as well use Google DNS.

PerroMart Discount Code

PerroMart SG is an online pet store in Singapore specializing in dog and cat food and products. It has an extremely wide range of food/products at very reasonable prices. During this COVID-19 period, it has free delivery!

For example, it has Himalayan Yak chew for dogs, which is a very rare dog chew that lasts very long and is very suitable for dogs. It also has exotic Kangaroo meat treats which are also very healthy for dogs. PerroMart also has overseas brands of dog food like the famous “Taste Of The Wild”.


PerroMart Discount Coupon

5% off coupon: PerroMart 5% Discount Coupon

Click on the above link to get a valuable 5% off coupon!


PerroMart Discount Codes

Use “PERROMART5” for $5 discount!

(The above code is valid as of April 2020.)


Absolute Bites Himalayan Yak Dental Sticks Dog Treats from PerroMart

100% Natural Himalayan Yak Chew comes from the ancient recipe of the people of Himalayas in Nepal.

KEY FEATURES

  • 100% Grain Free & Gluten Free Dog Chew
  • No Artificial Ingredient
  • Ultra Durable & Long Lasting
  • High in Protein & Minerals, Rich in Calcium
  • Ideal for Teething Dogs

In the surrounding Mt. Everest at more than 15,000 feet, these dog treats are made using traditional methods with yak and/or cow milk, and all natural products with no preservatives, binding agents. These yak chews are gluten free, and also provide health benefits like protein, minerals and calcium. An excellent and unique dog chew for all breeds and sizes.

Himalayan Yak chew is made from the milk of the Himalayan yak. Yaks can weigh up to 1,200 pounds (550 kg).

PR Solidarity Budget Application

Just to share this information with readers who may be Singapore PRs.

PR $300 for COVID-19 (with Singaporean spouse/children/parent)

Official source: Straits Times

Eligibility:

  • Adult PRs with Singaporean parents(s), spouse or child(ren) are eligible
  • Must be living in Singapore

Key date: 10 May (Sun)

Eligible PRs can apply with bank account details by 10 May at go.gov.sg/sppr. Payment will be made on 19 May (Tue).

Key date: From end-May

LTVP+ holders will receive payment by cheque via post. No action needed.

PRs who apply without bank account details will receive the payment by mailed cheque from end-May.


  • LTVP+ holders aged 21 and above, who are foreign spouses of Singaporeans, can receive the payout as well.
  • Eligible permanent residents may sign up for the one-off payout at https://go.gov.sg/sppr using their SingPass from now until May 10.

Disclaimer: The above information is correct as of 12 April 2020. Please double check with the official source on Straits Times for the official latest information: https://www.straitstimes.com/singapore/coronavirus-9-in-10-singaporeans-to-receive-600-each-on-april-14

Food for Chili Rasbora

How to feed Chili Rasbora / Phoenix Rasbora in Community Tank

Chili Rasbora / Phoenix Rasbora and other small Rasboras like dwarf Rasboras have the following characteristics:

  • Very small mouths
  • Quite shy
  • They are micropredators (require “animal” / high protein food)

How I feed them is actually to take Betta food (Hikari Betta Biogold), and crush them with a mortar and pestle. Betta is also a predator hence their dietary requirements are kind of the same (high protein rather than high vegetable content).  Then, together with the Neon Tetra pellets, pour it into the tank. There is bound to be food stuck to the container, which we use tank water to soak it and pour it out.

Repeat until all food is dispensed. Due to the numerous powder food in the water, the Neon Tetras are unable to snatch all the food, and the small Rasboras (Boraras Merah) are able to sneak in a few bites. At the end, all Rasboras are well fed as shown by their round bellies.

If the food is not crushed to powder, the Rasboras would not be able to swallow the food easily, and the end result is that most of the food is eaten by the Tetras. It took me quite a few months to figure the above procedure out (I was and still am quite new to fish keeping).


Hikari Betta Bio-Gold Baby Pellets Fish Food Bundle Bonus Pack 3 Pack

AI can’t predict how a child’s life will turn out even with a ton of data

Despite the great hype of AI, there are still many limitations of what AI can do. Real life is too complicated for a machine to figure out, at least currently.

Source: MIT Tech Review

Hundreds of researchers attempted to predict children’s and families’ outcomes, using 15 years of data. None were able to do so with meaningful accuracy.

Now a new study published in the Proceedings of the National Academy of Sciences casts doubt on how effective this approach really is. Three sociologists at Princeton University asked hundreds of researchers to predict six life outcomes for children, parents, and households using nearly 13,000 data points on over 4,000 families. None of the researchers got even close to a reasonable level of accuracy, regardless of whether they used simple statistics or cutting-edge machine learning.

“The study really highlights this idea that at the end of the day, machine-learning tools are not magic,” says Alice Xiang, the head of fairness and accountability research at the nonprofit Partnership on AI.

Install Windows on MacBook (Fast and Easy method)

Basically, you just need to follow the instructions in the YouTube video below. It is very easy and fast. The key software is VirtualBox.

You can download the official Windows 10 ISO disc image here: https://www.microsoft.com/en-gb/software-download/windows10ISO

Note that Windows 10 (Home) is free (you don’t have to activate it) and you can use it with only very minor restrictions.

Overall, the process to install Windows 10 on a Mac (using VirtualBox) is much easier than I expected.

Total time taken: Around 30-40 minutes (possibly faster if your download speed and RAM is fast)

Total cost: $0

Total space needed: Around 10-20 GB is needed initially. VirtualBox allows “dynamically allocated disks” which are faster to create and can grow to larger sizes. For example, if you set 50GB as your disk space (but only use 10 GB) then it will only occupy 10 GB on your Mac.