Precondition and path of the effective distrbution:an approach to state-owned enterprises

通过一个博弈分析 ,阐明了国有企业的有效收入分配必须同时满足资产所有者和劳动者的参与约束。以此为基础展开生产与分配的互动关系分析 ,并指出了这是国有企业实行有效收入分配的一条可行路径The effective distribution of state-owned enterprises must satisfy the participation constraints of both capital owner and labors by a game.On the basis, the relations between product and distribution is analysed and a feasible path of effective distribution is given

美国四轮全地形车标准新旧版本差异分析与研究

全地形车(All TErrAIn VEHIClE,简称ATV)是我国近年来发展迅猛的新兴车型,产品主要用于出口,而美国是我国全地形车主要出口对象国之一。本文通过对美国四轮ATV强制性安全标准AnSI/SVIA-1新旧版本的分析研究,阐述了我国ATV产品在设计、配置和性能等方面面临的技术壁垒,这对我国ATV产品出口美国具有重要指导意义。This paper focused on the analysis and research about American national standards ANSI/SVIA-1,introduced the technological barriers about design,performance and configuration of Chinese ATV products,which have the important value to export our ATV products to America

Individual Human Capital Investment Under the Situation of Adverse Selection

在中国高等教育实行收费制、高校毕业生就业率下降的条件下 ,为什么居民的高等教育投资需求还是这么强劲 ?本文用一个“逆向选择”下人力资本投资的博弈假说解释了上述现象。本文的基本结论是 ,在劳动力岗位实行竞争性配置、教育筛选机制不规范的前提下 ,人力资本的创造性替代导致了低能者的防御性反应 ,从而出现人力资本市场的“逆向选择” ;而“逆向选择”又进一步导致文凭的过度投资With self\|payment of university education and the decline of employmen trate for the people with university education, it is surprised to see that individuals' demand of university education investment remains very strong. This paper explained the above question by using game theory of human capital investment urder the situation of adverse selection. This paper ends with the conclusion that creative substitutions of human capital have given rise to lemons' defending reacts and adverse selection in the human capital market, which in turn causes further excessive investment in individual human capital

稀薄气体效应对高超声速飞行流动的影响分析

高超声速飞行器在飞行过程中,由于黏性耗散和激波压缩,流动一般具有高速、高温和热化学非平衡的特点:同时由于气动热约束,高超声速巡航要求在密度较低的大气环境中进行,稀薄气体效应显现,流动物理更为复杂。本文结合CFD与DSMC方法,分别模拟了平板、圆柱和球头等简单外形在氩气和近真实大气环境中飞行时的流场,分析了稀薄气体效应对高超声速流动的一些影响规律。研究发现,平板前缘存在局部稀薄气体效应,即使对于小

Diversity of bacterial community structure and its driving factors in three bays of Bohai Sea

[Background] Sustainable development of coastal ecosystem has become one of the most important concerns for people nowadays. Riverine output and anthropogenic interrupt have important impacts on the coastal environment. [Objective] In this study, we collected 12 samples from three transects including Bohai Bay, Liaodong Bay and Laizhou Bay to explore the microbial community and diversity in summer of 2015. [Methods] DNA was extracted from water samples by using DNA extraction kit. Samples were analyzed by Illumina HiSeq sequencing technology. We compared the differences among these three transects according to the analysis results. [Results] The diversity index and rarefaction curves showed significant differences among these three transects. The order of diversity value was Laizhou Bay>Bohai Bay>Liaodong Bay. The distribution of the dominant community was as follows: the proportion of Proteobacteria, Bacteroidetes, Cyanobacteria, Actinobacteria and Planctomycetes in the Bohai Bay was 39.8%, 25.7%, 22.4%, 5.85% and 4.38%, respectively. The dominant community proportion in Liaodong bay was Proteobacteria (37.8%), Bacteroidetes (25.7%), Cyanobacteria (17.8%), Actinobacteria (10.4%) and Planctomycetes (5.64%). While in Laizhou Bay there were only four dominant communities as follows: Proteobacteria (59.0%), Bacteroidetes (17.5%), Cyanobacteria (8.2%), Actinobacteria (7.88%). By using the principal component analysis (PCA) and Heatmap correlation analysis, we found that environmental factors were key roles in controlling the microbial diversity in the Bohai Sea. Among them, the concentration of nitrate was particularly significant according to the Mantel test analysis. [Conclusion] The microbial diversity in the three bays of Bohai Sea was very rich and multifarious. The population structure and species in the Laizhou Bay is the most complex and abundant among these three bays, and then it is Bohai Bay and Liaodong Bay. There was a significant correlation among microbial diversity, environmental factors and the spatial distribution. Above all, this study will provide a theoretical basis for further protection and ecological development of Bohai Sea

Synthesis and Biological Activity of Novel Bis-heterocyclic Compounds Containing 1H-Pyrazole and Thiazole

以苯肼、乙酰乙酸乙酯和氨基杂环为原料 ,合成了两类含双杂环的新型吡唑甲酰胺衍生物 ,其结构经元素分析、1HNMR ,MS及IR确证 .初步的生物活性测试结果表明 :部分化合物对水稻纹枯病菌、小麦赤霉病菌和苹果轮纹病菌具有良好的抑制效果 .In order to search for novel fungicides with high activity and low toxicity, a series of bis-heterocyclic compounds containing 1H-pyrazole and thiazole were designed and synthesized from phenyl hydrazine, ethyl acetoacetate and aromatic aminoheterolcycles. The structures of all new compounds were confirmed by elemental analysis, 1H NMR, IR and MS spectra. Preliminary bioassays indicated that some compounds showed fungicidal activity against Pellicularia sasakii, Gibberella zeave and Physalospora piricola.科技部国家“九五”重点科技攻关 (No .97 563 0 2 0 5)资助项

DSMC碰撞模型参数对高超声速化学反应流的影响

直接模拟蒙特卡罗(DSMC)方法是一种高效、精确的气体流动模拟方法。DSMC方法高效计算的关键在于它处理分子水平上的输运,内能松弛和化学反应过程使用的唯像模型。例如,Bird的变径硬球(VHS)模型是DSMC中处理弹性碰撞最成功的模型,该模型试图只再现气体粘度对温度的指数依赖关系,而不是对粒子之间的相互作用进行详细的建模。唯象模型参数的准确性对DSMC仿真的准确性至关重要。在早期的发展过程中,这些唯象碰撞模型参数通常是根据实验测得的有限温度范围输运系数数据进行校准的。人们已经认识到这些参数在高温范围内可能是不准确的,例如,在再入飞行中遇到的温度大于10000K的情况。因此,最近新的高温空气参数被推荐,通过对广泛使用的碰撞模型,如VHS和可变软球(VSS)模型,基于从头计算的碰撞积分数据进行参数标定。这些基于从头计算的碰撞参数的准确性已经被证明了。本文针对DSMC模拟最常用的唯象碰撞模型,通过拟合基于从头计算的碰撞积分数据对DSMC模型参数进行重新标定。在本文中,我们将通过使用一个最新开发的采用特定碰撞配对策略的DSMC程序研究碰撞参数对高超声速化学反应流动模拟流场特性的影响。圆柱体的高超声速反应流的初步结果表明,不同的DSMC碰撞模型参数,激波位置、表面热流率等流场特性有显著变化。本文将进行分析以确定模型参数影响流动特性的通道(例如扩散或反应过程)

基于微震监测的大范围破裂矿柱稳定性评价

柿竹园矿大范围破裂矿柱回采进行大爆破施工前,对装药区域的稳定性的监测与评价是确保大爆破施工安全与顺利实施的重要工作。基于柿竹园矿大范围破裂矿柱微震监测实例,详细分析了大范围破裂矿柱产生的原因,根据出矿对破裂矿柱稳定性的影响及微震监测结果,对破裂矿柱稳定性状态进行了评价。说明了微震监测能较准确地对破裂矿柱的活动状态进行监测,根据监测结果可以对破裂矿柱的稳定性状态进行较准确的评价与预警,为大爆破的施工与顺利实施提供了保障