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分享 苏德辰的蹄窝说错在哪?
苏德辰的蹄窝说错在哪?
暴雨流冲刷:山坡壶穴的成因 嵇少丞 Département des Génies Civil, Géologique et des Mines, École Polytechnique de Montréal, Montréal, Québec, H3C 3A7, Canada 内容提要: 暴雨是常见的气象现象, 雨水顺着山坡迅速 ...
嵇少丞 | 2017-4-21 04:30 | 114 次阅读|0 个评论
分享 数学难题挂谷猜想的百年回眸及其川普解
1917 年,日本数学家挂谷宗一( かけや そういちSoichi Kakeya) 提出了数学界著名的挂谷问题,其数学表述为:长度为1 的线段在平面上做刚体移动,方式不限,转动也罢,平移也行,总之不惜采用任何手段,只求转过180 度并回到原位置,试问:扫过的最小面积是多少? 他在提出此问题的同时,也给出了自己的猜 ...
kiwaho | 2017-4-19 01:41 | 19 次阅读|0 个评论
分享 从美国羚羊谷看基岩河道的底侵深掘机制
从美国羚羊谷看基岩河道的底侵深掘机制
从美国羚羊谷看基岩河道的底侵深掘机制 嵇少丞 原载《矿物岩石地球化学通报》,2017, Vol 36, No. 2, 356-358. 美国亚利桑那州印地安人纳瓦霍族(Navajo)部落的保留区内的羚羊谷(Antelope Canyon), 因野羚羊经常出没而获名, 当地印第安人将之称作“Tse bighanilin ...
嵇少丞 | 2017-4-17 10:06 | 180 次阅读|1 个评论 热度 1
分享 Rubik's Cube: swap three edge cubies
Rubik's Cube: swap three edge cubies
Rubik's Cube: swap three edge cubies "Hold the Rubik's Cube in this way: F(front) side facing you;" "U(up) side facing upwards; R(right) side facing to the right;" "B(back) side facing away from you; L(left) side facing to the left;" "D(down) side facing downwards." "The ...
分享 Rubik's Cube: Only Two Corner Cubies Twist
Rubik's Cube: Only Two Corner Cubies Twist
Rubik's Cube: Only Two Corner Cubies Twist "Hold the Rubik's Cube in this way: F(front) side facing you;" "U(up) side facing upwards; R(right) side facing to the right;" "B(back) side facing away from you; L(left) side facing to the left;" "D(down) side facing downwards." "The notations of describi ...
大毛忽洞 | 2017-3-27 09:59 | 40 次阅读|0 个评论
分享 白马: 简单说一下关于神州“房产”和“筹码”
时间有限,不寒暄,直奔主题。 如果大家一定要问,帝都的水泥盒子值多少钱,或者神州的水泥盒子值多少钱,也可以换个问题,赌场桌上的塑料片值多少钱? 塑料片值多少钱,这个由赌场来赋予,数字代表的可以是美元、港纸、比索或者津巴布韦一类的东西,关键看赌场背书的力度。可以肯定的是,被赋予的 ...
分享 Rubik's Cube: Three Corner Cubies Twist
Rubik's Cube: Three Corner Cubies Twist
"Three Corner Cubies Twist" "Hold the Rubik's Cube in this way: F(front) side facing you;" "U(up) side facing upwards; R(right) side facing to the right;" "B(back) side facing away from you; L(left) side facing to the left;" "D(down) side facing downwards." "The notations of describing the movement ...
大毛忽洞 | 2017-3-23 01:07 | 36 次阅读|0 个评论
分享 Rubik's Cube: (UR)^105=I
"Hold the Rubik's Cube in this way: F(front) side facing you;" "U(up) side facing upwards; R(right) side facing to the right;" "B(back) side facing away from you; L(left) side facing to the left;" "D(down) side facing downwards." "The notations of describing the movement of Rubik's Cube using these ...
大毛忽洞 | 2017-3-22 00:25 | 56 次阅读|0 个评论
分享 Rubik's Cube: swap four edge cubies
Rubik's Cube: swap four edge cubies
Rubik's Cube: swap four edge cubies "Hold the Rubik's Cube in this way: F(front) side facing you;" "U(up) side facing upwards; R(right) side facing to the right;" "B(back) side facing away from you; L(left) side facing to the left;" "D(down) side facing downwards." "The notations of describing the ...
大毛忽洞 | 2017-3-21 02:04 | 41 次阅读|0 个评论
分享 Rubik's Cube: Only two edge cubies flip
Rubik's Cube: Only two edge cubies flip
"Rubik's Cube: Only two edge cubies flip" "Hold the Rubik's Cube in this way: F(front) side facing you;" "U(up) side facing upwards; R(right) side facing to the right;" "B(back) side facing away from you; L(left) side facing to the left;" "D(down) side facing downwards." "The notations of describin ...
大毛忽洞 | 2017-3-19 11:49 | 45 次阅读|0 个评论
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