2014 IYPT CUPT
IYPT 2014 in Shrewsbury, United Kingdom
The IYPT 2014 will take place in Shrewsbury, United Kingdom.
Problems
As decided by the IOC 2013-08-01, released 2013-08-01
When throwing pebbles into water, watch the ripples;
Otherwise throwing the pebbles becomes a futile pastime.
Kozma Prutkov 1. Invent yourself
It is known that some electrical circuits exhibit chaotic behaviour. Build a simple circuit with such a
property, and investigate its behaviour.
2. Hologram
It is argued that a hologram can be hand made by scratching a piece of plastic. Produce such a ‘hologram’ with the letters ‘IYPT’ and investigate how it works.
3. Twisted rope
Hold a rope and twist one end of it. At some point the rope will form a helix or a loop. Investigate and explain the phenomenon.
4. Ball sound
When two hard steel balls, or similar, are brought gently into contact with each other, an unusual ‘chirping’ sound may be produced. Investigate and explain the nature of the sound.
5. Loaded hoop
Fasten a small weight to the inside of a hoop and set the hoop in motion by giving it an initial push. Investigate the hoop’s motion.
6. Bubble crystal
A large number of very small, similar air bubbles float on the surface of a soapy liquid. The bubbles will arrange themselves into a regular pattern similar to a crystalline lattice. Propose a method to obtain bubbles of a consistent size, and investigate the formation of such a bubble crystal.
7. Pot-in-pot refrigerator
The ‘pot-in-pot refrigerator’ is a device that keeps food cool using the principle of evaporative cooling. It consists of a pot placed inside a bigger pot with the space between them filled with a wet porous material, e.g. sand. How might one achieve the best cooling effect?
8. Freezing droplets
Place a water droplet on a plate cooled down to around -20 °C. As it freezes, the shape of the droplet may become cone-like with a sharp top. Investigate this effect.
9. Water bombs
Some students are ineffective in water balloon fights as the balloons they throw rebound without bursting. Investigate the motion, deformation, and rebound of a balloon filled with fluid. Under what circumstances does the balloon burst?
10. Coefficient of diffusion
Using a microscope, observe the Brownian motion of a particle of the order of micrometre in size. Investigate how the coefficient of diffusion depends on the size and shape of the particle.
11. Candle Power Plant
Design a device that converts the heat of a candle flame into electrical energy. Investigate how different aspects of the device affect its efficiency.
12. Cold balloon
As air escapes from an inflated rubber balloon, its surface becomes cooler to the touch. Investigate the parameters that affect this cooling. What is the temperature of various parts of the balloon as a function of relevant parameters?
13. Rotating saddle
A ball is placed in the middle of a rotating saddle. Investigate its dynamics and explain the conditions under which the ball does not fall off the saddle.
14. Rubber motor
A twisted rubber band stores energy and can be used to power a model aircraft for example. Investigate the properties of such an energy source and how its power output changes with time.
15. Oil stars
If a thick layer of a viscous fluid (e.g. silicone oil) is vibrated vertically in a circular reservoir, symmetrical standing waves can be observed. How many lines of symmetry are there in such wave patterns? Investigate and explain the shape and behaviour of the patterns.
16. Magnetic brakes
When a strong magnet falls down a non-ferromagnetic metal tube, it will experience a retarding force. Investigate the phenomenon.
17. Chocolate hysteresis
Chocolate appears to be a solid material at room temperature but melts when heated to around body temperature. When cooled down again, it often stays melted even at room temperature. Investigate the temperature range over which chocolate can exist in both melted and ‘solid’states and its dependence on relevant parameters.
Authors: John Balcombe, Samuel Byland, ?ukasz G?adczuk, Wee Wei Hsiung, Valery Koleboshin, Aliaksandr Mamoika, Ilya Martchenko, Othmar Marti, Martin Plesch, Rainer Reichle, Andrei Schetnikov, Erwin Handoko T anin, Kathryn Zealand
Problem selection committee: John Balcombe, Samuel Byland, Ilya Martchenko
Epigraph selected by Evgeny Yunosov
References
Below, find a link to supporting materials concerning the problems.
These materials are provided by independent persons or organizations, for the benefit of everyone who is interested. If you want your material listed here, contact the Executive Committee.
The IYPT wants to stress that any information found on any of these sites shall in no way be considered binding and authoritative.
We kindly remind all readers that the IYPT guidelines clearly stand for standard scientific conduct and proper procedures for citing material that is not one's own work, while the grading has a focus
on the novelty and consistency of the original research results presented.
华中科技大学2014届本科生毕业典礼李培根演讲稿
华中科技大学 2014 届本科生毕业典礼李培根演讲稿 6月23日，华中科技大学2014届本科生毕业典礼上，校长李培根院士16分钟的演讲，被掌声打断30 次。全场7700 余名学子起立高喊：“根叔！根叔！” 李培根在2014 余字的演讲稿中，把4 年来的国家大事、学校大事、网络热词等融合在一起。讲稿中，“俯卧撑”、“躲猫猫”、“打酱油”、“蜗居”、“被就业”等词语，让学生感到李培根与他们距离很近。 李培根表示，目前在中国的一些高校中，教授与学生的距离愈来愈大，老师在课后和学 生很少交流，去忙于创收等功利性的事情。他也希望国家能加大教育投入，使老师能把精力 从创收上转移到学生身上。 亲爱的2014 届毕业生同学们: 你们好! 首先,为你们完成学业并即将踏上新的征途送上最美好的祝愿. 同学们, 在华中科技 大学的这几年里,你们一定有很多珍贵的记忆! 你们真幸运,国家的盛世如此集中相伴在 你们大学的记忆中.08 奥运留下的记忆,不仅是金牌数的第一, 不仅是开幕式的华丽, 更是中华文化的魅力和民族向心力的显示;六十年大庆留下的记忆,不仅是领袖的挥手,不仅是自主研制的先进武器, 不仅是女兵的微笑, 不仅是队伍的威武整齐, 更是改革开放的历史和旗帜的威力;世博会留下的记忆,不仅是世博之夜水火相容的神奇, 不仅是中国馆的宏伟,不仅是异国场馆的浪漫,更是中华的崛起, 世界的惊异;你们一定记得某国总统 的傲慢与无礼, 你们也让他记忆了你们的不屑与蔑视; 同学们, 伴随着你们大学记忆的一定还有什锦八宝饭; 还有一个g2 的新词, 它将永远成为世界新的记忆. 近几年, 国家频发的灾难一定给你们留下深刻的记忆. 汶川的颤抖,没能抖落中国人民的坚强与刚 毅;玉树的摇动,没能撼动汉藏人民的齐心与合力.留给你们记忆的不仅是大悲的哭泣, 更是大爱的洗礼;西南的干旱或许使你们一样感受渴与饥, 留给你们记忆的, 不仅是大 地的喘息,更是自然需要和谐, 发展需要科学的道理. 在华中大的这几年,你们会留下一生中特殊的记忆. 你一定记得刚进大学的那几分稚气,父母亲人送你报到时的情景历历; 你或许记得"考前突击而带着忐忑不安的心情走向考场时的悲壮" , 你也会记得取得好成绩时的欣喜; 你或许记得这所并无悠久历史的学校不断追求卓越的故事; 你或许记得裘 法祖院士所代表的同济传奇以及大师离去时同济校园中弥漫的悲痛与凝重气息; 你或许记得人文素质讲堂的拥挤,也记得在社团中的奔放与随意; 你一定记得骑车登上"绝望坡" 的喘息与快意; 你也许记得青年园中令你陶醉的发香和桂香, 眼睛湖畔令你流连忘返的圣洁或妖娆; 你或许" 记得向喜欢的女孩表白被拒时内心的煎熬" , 也一定记得那初吻时的如醉如痴. 可是, 你是否还记得强磁场和光电国家实验室的建立?是否记得创新研究院和启明学院的耸起?是否记得为你们领航的党旗?是否记得人文讲坛上精神矍铄的先生叔子?是否记得倾听你们诉说的在线的" 张妈妈" ? 是否记得告诉你们捡起路上树枝的刘玉老师?是否记得应立新老师为你们修改过的简历, 但愿它能成为你们进入职场的最初记
2014高考英语(北京卷)完形填空真题含答案详解
2014年高考英语（北京卷）完形填空真题含答案详解 The Fitting-in of Suzy Khan The first time I saw Suzy Khan, I knew I had to help her. She was really small for her age of 12. The boys in my class often 1_ about her and laughed their heads off. She would open a book, pretending to read, with tears dropping on the open page. All I knew was that she was an orphan (孤儿) from Africa. She had just been adopted by a family in town who 2 that the best way for her to learn American ways of life was to be with American kids. I looked down at this 3_ girl and promised myself that somehow I would help her. But how could I help her 4 in with us? There had to be a 5_ . One day, when I went into the classroom, I saw that Suzy had 6 her geography book to a picture of a train, and in her notebook, she had made a(n) 7_ copy. I was surprised and thought that she could do something in the coming 8_ show. So, I took her to see the art teacher, Miss Parker, and showed her what Suzy had 9_ . “why, it’s wonderful,” said Miss Parker, who the n showed us a poster she had painted 10_ the talent show. “I need more of these, but I just don’t have enough11 . Could you help me, Suzy?” On the day of the talent show, Suzy’s 12 were everywhere ---- all over the hall and all over the school, each one different. “And finally,” said Mr. Brown, the schoolmaster, at the end of the show, “we have a (n)_13_award. I’m sure you’ve all noticed the wonderful posters.” Everyone nodded. “One of our own students 14 them.” I could hear everyone whispering. “Who in our school could draw 15 well?” Mr. Brown waited a while before saying, “ 16 this student worked so hard on the posters, she deserves a 17 ,too. Our mystery(神秘) artist is our new student ---- Suzy Khan!” Mr. Brown thanked her for all the wonderful posters and gave her a professional artist’s set. “Thank you,” she cried. I 18 , at that time when I was looking at her excited face, she’d probably never 19 anything in her whole life. Everyone started to 20 their hands. Suzy Khan gave them a shy smile and the applause was deafening. I knew then Suzy was going to be all right.
学院2014届毕业典礼学生代表发言稿
学院2014届毕业典礼学生代表发言稿 尊敬的各位老师、亲爱的各位同学： 大家上午好！ 今天是我们大学阶段最后一次欢聚，是我们向母校挥手告别的日子，也是我们各奔东西，开启人生新征程的日子。这个离别的时刻，能代表自动化站在这里发言，我感到非常的荣幸，此刻，百感交集！ 首先，请允许我代表全体毕业生向辛勤培育我们的各位领导、老师，表达最衷心的感谢；向这么多年来辛勤操劳的父母，表示最崇高的敬意；向四年来一起朝夕相处兄弟姐妹们，表达最真最诚的祝福。 四年前，化院在我们心中是一座神圣的殿堂，我们在外头，她在里头！ 四年里，化院是一架阶梯，我们在前头，时光在后头！ 如今，四年过去啦，化院又成了我们扬帆起航的码头，我们在这头，梦想在那头！ 四年短暂却精彩，爱过也恨过，失去过也得到过，一起通宵熬夜，一起赖床睡懒觉，一起去图书馆占位子，一起在餐馆里胡吃海喝，欢笑，悲伤，争吵，推心置腹的卧谈…这一刻，四年的回忆历历在目。经历了很多，我们成长了，开始收敛指点江山的锐气，告别那段愤世嫉俗，自命不凡的年华，蜕变成一个彬彬有礼，温恭自虚的人，我们不再害怕寂寞，却无比害怕不成功。正像马丁—路德金说的，我有一个梦，我们所有人都有一个梦！今天开始，我们就要去追逐我们的梦，去追逐怒放的生命。 曾有人问我大学四年收获了什么，我想骄傲的说，我收获了青春最美的回忆，收获了最纯真的友谊，收获了勇敢去实现梦想的自信，和对生活的感激， 今朝毕业，不诉离伤，他日重逢，各领风骚！
至此毕业之际，再次祝愿老师们身体健康，祝愿同学们工作生活顺利，梦想成真，祝福母校兴旺发达，祝福电气信息学院蒸蒸日上。再创辉煌！ 谢谢大家！
2014高考英语真题 全国卷2 完形填空 试题及答案详解
2014高考英语真题全国卷2 完形填空试题及答案详解 Joe Simpson and Simon Yates were the first people to climb the West Face of the Siula Grande in the Andes mountains. They reached the top 1_, but on their way back conditions were very 2 . Joe fell and broke his leg. They both knew that if Simon 3 alone, he would probably get back 4 . But Simon decided to risk his 5 and try to lower Joe down the mountain on a rope(绳). As they 6 down, the weather got worse. Then another 7 occurred. They couldn't see or hear each other and, 8 , Simon lowered his friend over the edge of a precipice(峭壁). It was 9 for Joe to climb back or for Simon to pull him up. Joe's 10 was pulling Simon slowly towards the precipice. 11, after more than an hour in the dark and the icy cold, Simon had to 12 . In tears, he cut the rope. Joe 13 into a large crevasse(裂缝) in the ice below. He had no food or water and he was in terrible pain. He couldn't walk, but he 14 to get out of the crevasse and started to 15 towards their camp, nearly ten kilometers 16_. Simon had 17 the camp at the foot of the mountain. He thought that Joe must be 18 , but he didn't want to leave 19_. Three days later, in the middle of the night, he heard Joe's voice. He couldn't 20 it. Joe was there, a few meters from their tent, still alive. 1. A.hurriedly B.carefully C.successfully D.early 2. A.difficult B.similar C.special D.normal 3. A.climbed B.worked C.rested D.continued 4. A.unwillingly B.safely C.slowly D.regretfully 5. A.fortune B.time C.health D.life 6. https://www.360docs.net/doc/7e17386371.html,y B.settled C.went D.looked 7. A.damage B.storm C.change D.trouble 8. A.by mistake B.by chance C.by choice D.by luck 9. A.unnecessary B.practical C.important D.impossible 10. A.height B.weight C.strength D.equipment 11. A.Finally B.Patiently C.Surely D.Quickly 12. A.stand back B.take a rest C.make a decision D.hold on
外文翻译中文版(完整版)
毕业论文外文文献翻译 毕业设计（论文）题目关于企业内部环境绩效审计的研究翻译题目最高审计机关的环境审计活动 学院会计学院 专业会计学 姓名张军芳 班级09020615 学号09027927 指导教师何瑞雄
最高审计机关的环境审计活动 1最高审计机关越来越多的活跃在环境审计领域。特别是1993-1996年期间，工作组已检测到环境审计活动坚定的数量增长。首先，越来越多的最高审计机关已经活跃在这个领域。其次是积极的最高审计机关，甚至变得更加活跃：他们分配较大部分的审计资源给这类工作，同时出版更多环保审计报告。表1显示了平均数字。然而，这里是机构间差异较大。例如，环境报告的数量变化，每个审计机关从1到36份报告不等。 1996-1999年期间，结果是不那么容易诠释。第一，活跃在环境审计领域的最高审计机关数量并没有太大变化。“活性基团”的组成没有保持相同的：一些最高审计机关进入，而其他最高审计机关离开了团队。环境审计花费的时间量略有增加。二，但是，审计报告数量略有下降，1996年和1999年之间。这些数字可能反映了从量到质的转变。这个信号解释了在过去三年从规律性审计到绩效审计的转变（1994-1996年，20％的规律性审计和44％绩效审计;1997-1999：16％规律性审计和绩效审计54％）。在一般情况下，绩效审计需要更多的资源。我们必须认识到审计的范围可能急剧变化。在将来，再将来开发一些其他方式去测算人们工作量而不是计算通过花费的时间和发表的报告会是很有趣的。 在2000年，有62个响应了最高审计机关并向工作组提供了更详细的关于他们自1997年以来公布的工作信息。在1997-1999年，这62个最高审计机关公布的560个环境审计报告。当然，这些报告反映了一个庞大的身躯，可用于其他机构的经验。环境审计报告的参考书目可在网站上的最高审计机关国际组织的工作组看到。这里这个信息是用来给最高审计机关的审计工作的内容更多一些洞察。 自1997年以来，少数环境审计是规律性审计（560篇报告中有87篇，占16％）。大多数审计绩效审计（560篇报告中有304篇，占54％），或组合的规律性和绩效审计（560篇报告中有169篇，占30％）。如前文所述，绩效审计是一个广泛的概念。在实践中，绩效审计往往集中于环保计划的实施（560篇报告中有264篇，占47％），符合国家环保法律，法规的，由政府部门，部委和/或其他机构的任务给访问（560篇报告中有212篇，占38％）。此外，审计经常被列入政府的环境管理系统（560篇报告中有156篇，占28％）。下面的元素得到了关注审计报告：影响或影响现有的国家环境计划非环保项目对环境的影响;环境政策;由政府遵守国际义务和承诺的10％至20％。许多绩效审计包括以上提到的要素之一。 1本文译自：S. Van Leeuwen.(2004).’’Developments in Environmental Auditing by Supreme Audit Institutions’’ Environmental Management Vol. 33, No. 2, pp. 163–1721
江苏2014各地高考模拟考试完型填空题收集1
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在2014届高三毕业典礼上的讲话
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