Based on the current situation of urbanization development in West China, this paper analyses main factors responsible for sluggish urbanization in West China as follows: impact of environment factor, impact of popula...Based on the current situation of urbanization development in West China, this paper analyses main factors responsible for sluggish urbanization in West China as follows: impact of environment factor, impact of population quality and quantity, lagging of public product service, stagnancy of technological development, backwardness of slow growth, and rigidity of system building. And then this paper analyses the restriction mechanism of urbanization in West China: at the superficial level, the constraints of urbanization in West China arise from the shortage of capital; at the profound level, the backward culture contributes to the constraints of urbanization in West China. The thread of resolving restriction mechanism of urbanization in West China is put forward from system, economy and culture. On the basis of this thread, we construct the power system for the development of urbanization in West China. The power system for urbanization in West China should be propelled by "four forces", namely, pull of external forces, cohesive strength of regional market environment, expansion power inside countryside, traction of industrial structure adjustment. Innovation is the engine of impetus for urbanization in West China; spatial clustering and modernization of industry is the major driving force for urbanization; the government behaviour, driving of foreign investment, great projects and other forces are supplementary power. Via the main power, we should take the market as medium to achieve the role of power in promoting urbanization.展开更多
A statistically significant research finding should not be defined as a P-value of 0.05 or less, because this definition does not take into account study power. Statistical significance was originally defined by Fishe...A statistically significant research finding should not be defined as a P-value of 0.05 or less, because this definition does not take into account study power. Statistical significance was originally defined by Fisher RA as a P-value of 0.05 or less. According to Fisher, any finding that is likely to occur by random variation no more than 1 in 20 times is considered significant. Neyman J and Pearson ES subsequently argued that Fisher's definition was incomplete. They proposed that statistical significance could only be determined by analyzing the chance of incorrectly considering a study finding was significant(a Type Ⅰ?error) or incorrectly considering a study finding was insignificant(a Type Ⅱ error). Their definition of statistical significance is also incomplete because the error rates are considered separately, not together. A better definition of statistical significance is the positive predictive value of a P-value, which is equal to the power divided by the sum of power and the P-value. This definition is more complete and relevant than Fisher's or Neyman-Peason's definitions, because it takes into account both concepts of statistical significance. Using this definition, a statistically significant finding requires a P-value of 0.05 or less when the power is at least 95%, and a P-value of 0.032 or less when the power is 60%. To achieve statistical significance, P-values must be adjusted downward as the study power decreases.展开更多
区块链是随着比特币等数字加密货币逐渐兴起而盛行的一种新型去中心化分布式系统,具有去中心化、时序数据、集体维护、可编程和安全可信等特点.目前,区块链已引起政府部门、金融机构、科技企业和资本市场的高度重视与广泛关注.如何在一...区块链是随着比特币等数字加密货币逐渐兴起而盛行的一种新型去中心化分布式系统,具有去中心化、时序数据、集体维护、可编程和安全可信等特点.目前,区块链已引起政府部门、金融机构、科技企业和资本市场的高度重视与广泛关注.如何在一个去中心化的分布式系统中高效地达成共识是区块链技术研究的重要问题.本文从工作量证明(Proof of work,PoW)共识算法的挖矿困境入手,分析PoW共识过程中矿工策略选择的纳什均衡存在条件.利用零行列式(Zero determinant,ZD)策略对矿工策略选择进行优化,并通过数值仿真来验证优化算法的有效性.概括来说,本文从博弈论角度来理解和剖析PoW共识算法,为进一步设计基于博弈论的共识算法提供新的思路和方法.展开更多
The preparation of ultra fine Y A G( Y3 Al5 O12) po w der through co precipitation techniquew as investigated . The for m ation tem perature of Y A G w as lo wered belo w 800 ℃ by carefullycontrolling process...The preparation of ultra fine Y A G( Y3 Al5 O12) po w der through co precipitation techniquew as investigated . The for m ation tem perature of Y A G w as lo wered belo w 800 ℃ by carefullycontrolling process para m eters . Ultra fine Y A G po w der w ith even size distribution , spheri cal shapes , and 40 n m particle size has been produced . It is found that for m ation of Y A Gisnot through the Y A M an d Y A Pinter mediate phases that are often observed during the synthe sis of Y A G by m ixed oxide m ethod . The sm all particle size of the precursor po w der , them olecular scale mixing of the constituents , and the poly m orphic transfor m ation of Al2 O3during heating accou nt m ainly for the reduction of for m ation tem perature of Y A Gan d the e lim ination of inter m ediate Y A M and Y A Pphases .展开更多
基金Supported by the National Natural Science Foundation (51178372)
文摘Based on the current situation of urbanization development in West China, this paper analyses main factors responsible for sluggish urbanization in West China as follows: impact of environment factor, impact of population quality and quantity, lagging of public product service, stagnancy of technological development, backwardness of slow growth, and rigidity of system building. And then this paper analyses the restriction mechanism of urbanization in West China: at the superficial level, the constraints of urbanization in West China arise from the shortage of capital; at the profound level, the backward culture contributes to the constraints of urbanization in West China. The thread of resolving restriction mechanism of urbanization in West China is put forward from system, economy and culture. On the basis of this thread, we construct the power system for the development of urbanization in West China. The power system for urbanization in West China should be propelled by "four forces", namely, pull of external forces, cohesive strength of regional market environment, expansion power inside countryside, traction of industrial structure adjustment. Innovation is the engine of impetus for urbanization in West China; spatial clustering and modernization of industry is the major driving force for urbanization; the government behaviour, driving of foreign investment, great projects and other forces are supplementary power. Via the main power, we should take the market as medium to achieve the role of power in promoting urbanization.
文摘A statistically significant research finding should not be defined as a P-value of 0.05 or less, because this definition does not take into account study power. Statistical significance was originally defined by Fisher RA as a P-value of 0.05 or less. According to Fisher, any finding that is likely to occur by random variation no more than 1 in 20 times is considered significant. Neyman J and Pearson ES subsequently argued that Fisher's definition was incomplete. They proposed that statistical significance could only be determined by analyzing the chance of incorrectly considering a study finding was significant(a Type Ⅰ?error) or incorrectly considering a study finding was insignificant(a Type Ⅱ error). Their definition of statistical significance is also incomplete because the error rates are considered separately, not together. A better definition of statistical significance is the positive predictive value of a P-value, which is equal to the power divided by the sum of power and the P-value. This definition is more complete and relevant than Fisher's or Neyman-Peason's definitions, because it takes into account both concepts of statistical significance. Using this definition, a statistically significant finding requires a P-value of 0.05 or less when the power is at least 95%, and a P-value of 0.032 or less when the power is 60%. To achieve statistical significance, P-values must be adjusted downward as the study power decreases.
文摘区块链是随着比特币等数字加密货币逐渐兴起而盛行的一种新型去中心化分布式系统,具有去中心化、时序数据、集体维护、可编程和安全可信等特点.目前,区块链已引起政府部门、金融机构、科技企业和资本市场的高度重视与广泛关注.如何在一个去中心化的分布式系统中高效地达成共识是区块链技术研究的重要问题.本文从工作量证明(Proof of work,PoW)共识算法的挖矿困境入手,分析PoW共识过程中矿工策略选择的纳什均衡存在条件.利用零行列式(Zero determinant,ZD)策略对矿工策略选择进行优化,并通过数值仿真来验证优化算法的有效性.概括来说,本文从博弈论角度来理解和剖析PoW共识算法,为进一步设计基于博弈论的共识算法提供新的思路和方法.
文摘The preparation of ultra fine Y A G( Y3 Al5 O12) po w der through co precipitation techniquew as investigated . The for m ation tem perature of Y A G w as lo wered belo w 800 ℃ by carefullycontrolling process para m eters . Ultra fine Y A G po w der w ith even size distribution , spheri cal shapes , and 40 n m particle size has been produced . It is found that for m ation of Y A Gisnot through the Y A M an d Y A Pinter mediate phases that are often observed during the synthe sis of Y A G by m ixed oxide m ethod . The sm all particle size of the precursor po w der , them olecular scale mixing of the constituents , and the poly m orphic transfor m ation of Al2 O3during heating accou nt m ainly for the reduction of for m ation tem perature of Y A Gan d the e lim ination of inter m ediate Y A M and Y A Pphases .