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數學男孩圓周率之旅 (臺灣大學名譽教授 張鎮華): 3. 143. 1416 3. 1415926 201931. 4 108
作者: 張鎮華
圓是自然界與生活上常見的美妙形狀，它是神賜給人類的寶貴禮物，人自古以來就致力於瞭解其性質。要瞭解圓，就要瞭解圓周率，這個反應它的一個重要常數，小學時老師告訴我們圓周率是3.14，長大一點以後精確度提高到3.1416，到後來就用符號記為π。
整本書以數學男孩吉拉一生的經歷，串起古今圓周率計算的工作，並適度介紹與圓周率相關的數學。故事起自吉拉和女兒們討論圓周率，轉而回憶吉拉小時的求學經驗。
吉拉小學國語老師挑戰他們計算面積，接到初中學習幾何知識配合根號求值解決問題，輾轉到古代人對於圓周率的計算，集其大成者是南北朝數學家祖沖之，他求得的3.1415926是之後一千年內最精確的值。
吉拉四姊計算平方數的挑戰，及他高中時對於完全數的迷戀，指向數學上的計算很容易到達人力的極限。吉拉學習電腦的故事逐漸展現，數學知識加上電腦的威力，讓一些人力不能及的計算，完成到前所未有的境界。現代人對於圓周率的計算就是這個浪潮下的一個小浪花，其中2019年日籍女工程師岩尾算到小數點後31.4兆位數是一個旅程碑。
整本書以數學男孩吉拉一生的經歷，串起古今圓周率計算的工作，並適度介紹與圓周率相關的數學。故事起自吉拉和女兒們討論圓周率，轉而回憶吉拉小時的求學經驗。
吉拉小學國語老師挑戰他們計算面積，接到初中學習幾何知識配合根號求值解決問題，輾轉到古代人對於圓周率的計算，集其大成者是南北朝數學家祖沖之，他求得的3.1415926是之後一千年內最精確的值。
吉拉四姊計算平方數的挑戰，及他高中時對於完全數的迷戀，指向數學上的計算很容易到達人力的極限。吉拉學習電腦的故事逐漸展現，數學知識加上電腦的威力，讓一些人力不能及的計算，完成到前所未有的境界。現代人對於圓周率的計算就是這個浪潮下的一個小浪花，其中2019年日籍女工程師岩尾算到小數點後31.4兆位數是一個旅程碑。
作者
張鎮華
退休後現為臺灣大學名譽教授。年輕時取得美國康乃爾大學運籌學博士學位，回臺灣後先後在中央大學、交通大學、臺灣大學任教。一生致力於離算數學及組合最優化研究，特別是圖論及其演算法，發表過專業論文兩百多篇及專書三冊。曾參與108數學課程綱要研修，撰寫相關介紹文章數十篇。
張鎮華
退休後現為臺灣大學名譽教授。年輕時取得美國康乃爾大學運籌學博士學位，回臺灣後先後在中央大學、交通大學、臺灣大學任教。一生致力於離算數學及組合最優化研究，特別是圖論及其演算法，發表過專業論文兩百多篇及專書三冊。曾參與108數學課程綱要研修，撰寫相關介紹文章數十篇。
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4.8 ★★★★★
Based on 30 reviews
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Product Reviews
★★★★★ 5
Works
Size: 3 Panel-102'', Color: Beige, Size: 3 Panel-102'', Color: Beige
It’s beige and not white. Once install - hard to disinstall. Need a drill to put it together
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Reviewed in the United States on May 4, 2026
★★★★★ 3
Does the job, but assembling by yourself is a nightmare
Size: 4 Panel-88'', Color: Black
Does it do the job? Yes, although as others said there are small gaps but it's not a huge deal. The price is also good. But the reason I'm giving it a 3/5 is simply because the assembly for this was a complete nightmare. I honestly don't think I would recommend this to anyone unless they have another person to help them assemble it, because doing it by myself was terrible. I don't think I'd buy this again, I think I'd opt to just spend a bit more money and save myself the trouble personally.
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Reviewed in the United States on May 29, 2026
★★★★★ 4
Reasonably adequate room divider
Size: 4 Panel-88'', Color: Beige
I'm reviewing this as I assemble it.
Couple things:
1. I didn't expect as much assembly. I've ordered dividers before and they more-or-less came as one unit. Sometimes the panels needed screwing together. These require complete assembly and come largely as three rods: two make up vertical columns and snap together. Another one (called part "C") makes the horizontal columns and you have two of these per panel (one attaches to part "A" and the other part "B"). These parts are metal with a plastic shim. Using the wood screws to attach to part "C" is a real pain in the neck. There's not much holding the panel in place so it's a little tricky.
One tactic I've found while I'm assembling that works for the initial connections from parts A and B to their respective "C" rods is to hold the screw in place with a screw driver and then rotating the rod around the screw. This will do a number on your hands if you aren't wearing gloves. This obviously doesn't work when completing the connection.
Using a driller driver on this is really near impossible because there isn't anything you can use to secure it in place. You can use it on the first panel, but as it gets longer, it becomes increasingly difficult and because it isn't wood, it's really tight. I considered drilling larger pilot holes but since there are only 4x4=16 screws I need to screw in, I just decided to use my screw driver to complete it.
2. Also related to assembly. When completing the panels (attaching parts "A" and "B" to parts "C" that have the cloth cover on it), you have to be careful that when you tighten that side that it isn't loosening the other side. Because the pilot holes are so tight, you can end up rotating the rod, which rotates it in the same direction as looser on the original side. Having someone hold the "C" rod in place while you screw it in is probably the easiest approach. I didn't have a 2nd person, so I just had to keep flipping back and forth and tightening both sides as I screwed it in. Not the worlds biggest deal, but annoying nonetheless.
3. The way the instructions are written, they seem to suggest building this thing progressively; that is, you do panel 1, then 2, connect them together, then do 3 and connect it, etc. I took a different route that I suspect saved me quite a bit of trouble, and I assembled all four panels first and THEN connected everything together.
4. For the love of God make sure you check that the plastic tip is on the same side for every panel. Otherwise, you have to take one side apart again and reverse it. On the bright side, if this happens, you've essentially bored out the pilot holes to be the correct size... which is having me question if I shouldn't have just bored them out to the appropriate width in the first place.
5. Attaching all of the panels together is also an enormous pain in the ass unless you happen to have an 88" long elevated surface. Attaching the legs either requires you to elevate one side, which will invariably twist the inexplicably cheap material in the bottom connectors... or you can attach them sideways... or you can put this thing upright, having two people hold the panels in place while you use the allen wrench to tighten the bolts on the underside. None of those are particularly great options.
NOW on to the utility itself.
1. The panels do let some light through (I didn't believe their advertising, and that was one of the reasons that I bought beige, is that I wanted it to not be too dark). They aren't transparent though, so it isn't that far off from their description. They functionally work great, and keep the mess of wires hidden and when I'm sitting at my desk, actually reflect quite a bit of light into my office. Great!
2. My wife has described these as "the most hideous piece of furniture ever conceived of by man." So it does not have spouse approval factor. Granted, she will seldom be in my office area, so that isn't the end of the world.
3. These are really hard to align in a way that doesn't look a little tacky. There are some plastic connectors but they don't do a bang up job of keeping these in place. Each panel is slightly tilted and it's... quite obvious. I may at some point make my own improvements to these to help make them more level. It's not a particularly expensive product so I wasn't expecting much so it's fine and I'm not going to ding them on the rating because of it.
All said, would I buy this product again? Probably not. It's assembly was ~90 minutes which is about 75 minutes longer than I was anticipating spending on this (not including the 5 minute writeup that I'm doing here). But am I going to return it? Also no, if for no other reason I'd be just as annoyed taking it apart and putting it in the original box to return it.
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Reviewed in the United States on October 31, 2023
★★★★★ 5
Easy peasy
Size: 1 Panel, Color: Black
Bought this single-panel room divider for my son so he has a little privacy when he has to keep his camera on for online classes.
It’s lightweight, easy to set up, and does the job—he can focus without me photobombing in the background. He can feel like he has his own tiny corner office, even if it’s just the basement.
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Reviewed in the United States on March 29, 2026
★★★★★ 5
It serves it's purpose!!
Size: 1 Panel, Color: Black
Product really works well & serves it's purpose! Great height & width. It's flimsy, but it will stand still when put in place.
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Reviewed in the United States on April 4, 2025