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101.
Based on a long-term ethnographic study of a group of French boxers, this article retraces the biography of one of its members. Éric was an average boxer who never truly mastered the art of dodging his opponents. He never left the ranks of amateur boxing either, although in fact he never truly hoped he would step into the limelight reserved for the very few champions who make it. His anonymous and relentless commitment to boxing was in fact filled with a different meaning that his ethnobiography brings to light. His commitment to boxing can be better understood in light of the trials he faced in “the poor life”, a life he described as flavorless, mired in unemployment and survival delinquency. Despite his repeated defeats in the ring, for him boxing was the only part of his identity that elevated his status and set him apart from those who only had the streets to hang out on. By revealing the meaning he gave to his pugilism, Éric’s ethnobiography offers a new perspective on the links between boxing, violence, and poverty. It also paves the way for exploring the dark side of a leisure activity and its struggles that extend far beyond the ring itself.  相似文献   
102.
汽车装配主要由冲压、车身焊接、喷涂、总装四大工艺组成.电阻点焊质量的好坏直接影响整车的质量,必须引起供应商的重视并严格控制点焊质量.文章根据供应商质量管理工作经验,总结了控制和提高点焊质量的实用方法  相似文献   
103.
We analyze a monopolist's incentive to innovate a new antibiotic which is connected to the same pool of antibiotic treatment efficacy as is another drug produced by a generic industry. We outline the differences of antibiotic use under market conditions and in the social optimum. A time- and state-dependent tax-subsidy mechanism is proposed to induce the monopolist and generic industry to exploit antibiotic efficacy optimally.  相似文献   
104.
根据内齿轮齿形的加工形成原理,本文对展切式内压齿轮滚刀的齿形基本圆锥蜗杆进行了理论探讨,并推导出齿形侧铲面刃形的方程。  相似文献   
105.
扭曲叶片的绘型常采用的单锥面展开法 ,因是基于局部相似 ,所以 ,存在误差 ,无法分析 ,难以编程。笔者在有关水泵问题研究中 ,对扭曲叶片绘型的单锥面展开法进行了改进 ,给出利用非等变角对数螺旋线进行叶片绘型的新方法。这种方法能够很好地控制β角的变化规律 ,并能对误差进行分析和修正 ,便于编程计算 ,易于操作 ,在水泵设计中有广泛的实用价值。  相似文献   
106.
A method that enables determination of maximum amplitudes of standing vibration waves, off-horizontal angles of the conductors, moments of resistance, and cutting forces in any cross section of any type of conductor and connector with the help of SVT-connector software is described. Comparative values of the mentioned parameters at the outlet of the conductor from rigid dress and at the inlet to the connector are presented.  相似文献   
107.
水工混凝土耐久性研究的新进展   总被引:9,自引:0,他引:9  
国家“九五”攻关“混凝土抗冻性研究”和“耐化学腐蚀及高耐蚀材料的研究”两个专题中,包括了高抗冻超抗冻混凝土的开发及应用、高强混凝土的抗冻性、混凝土抗冻性的定量化设计、荷载和高浓度硫酸盐侵蚀的研究,以及压力水下混凝土渗漏溶蚀的研究等子题。研究成果已通过国家科技部的鉴定,并在三峡大坝等工程中得到了应用,取得了良好的效果。  相似文献   
108.
This paper builds on prior research by analysing the impact of cultural factors on both price clustering and price resistance in China's stock markets. The results support the presence of cultural factors impacting on price clustering with the digit 8 showing a higher propensity for clustering and the digits 4 and 7 showing a lower propensity in the A‐share market, where stock is denominated in renminbi and traded by mainland Chinese. These results are further supported by an analysis of the B‐share market, where cultural factors have no (or less) impact on the price of Chinese stocks traded by foreign investors in US dollars (or in Hong Kong dollars). A range of measures for price resistance show the digits 0 and 5 to be significant resistance points in the A‐share market. Although digit 8 cannot be considered as a resistance point, its resistance level is highest among the remaining numbers. In conclusion, cultural factors help to explain not only price clustering in the Chinese stock markets but price resistance levels as well, albeit at a weak level.  相似文献   
109.
某电站混流式水轮机组在部分负荷时机组出力大幅摆动,真机试验结果显示尾水管涡带频率与发电机低频振荡频率接近,二者产生共振导致功率波动。本文采用CFD方法对该电站混流式水轮机进行了三维非定常数值模拟,对包括电站现用泄水锥、加长型泄水锥、在尾水管内安装阻尼栅、在尾水管内安装导流板等4种方案下水轮机内部非定常流动进行了仿真,对比分析了各种方案对尾水管内涡带形状和压力脉动的影响。计算结果表明:加长泄水锥能降低压力脉动的幅值,但不能改变压力脉动频率;相比于阻尼栅,在尾水管中安装导流板能更有效地改变尾水管水压力脉动的主频并减小压力脉动的幅值,且对水轮机效率的影响较小。  相似文献   
110.
The different state of the submerged vegetation has different influences on the flow resistance. This paper explores the relationship between the state and the resistance of an individual submerged vegetation, and the relative bending rigidity of the submerged vegetation is determined by the state of the submerged vegetation. Based on the experimental observations, the state and the resistance of an individual submerged vegetation are analyzed under different inflow conditions. At the same time, the influences of the various submerged vegetations on the flow resistance are discussed under the same inflow conditions. Some interesting relationships are obtained between the flow resistance and the relative bending rigidity of the submerged vegetation, and it is shown that the flow resistance increases with the increase of the relative bending rigidity of the submerged vegetation, and they are positively correlated.  相似文献   
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