电子秒表自动计时的研究

利用光电原理，对常用的计时工具——电子秒表实现自动控制，能有效地消除手动操作所带来的误差。它可广泛应用于对运动物体的速度、加速度的测量实验，还可用来验证牛顿第二定律、机械能守恒等物理实验，同时也适用于对时间测量精度要求较高的场合。     

对存续企业退出的探讨

存续企业是国有集团公司中未上市部分.在改革进入攻坚阶段,存续企业的改革至关重要.依据非自由退出模型,存续企业的退出选择面临障碍,负外部性大、成本大.因此着眼于存续企业的存续,谋求整个集团公司的协调发展才是改革的较好选择.     

农户分化、乡土依赖与集体收益分配权退出

基于3个农村改革试验区716个农户的微观数据,实证分析农户分化、乡土依赖对农户集体收益分配权退出意愿的影响。结果表明,农户的不断分化并未提高其集体收益分配权退出意愿,分化程度较高的农户更倾向于继续持有集体收益分配权,土地、宅基地的退出对集体收益分配权退出意愿未产生显著影响,但对所在村的心理依赖水平有着显著的反向影响,即在集体收益分配权的退出中,对其退出意愿产生影响的更多是农户对乡土的心理依赖,而非现实依赖。这要求在进一步探索中,既要有改革的紧迫感,完善退出机制,引导符合条件的农户理性退出集体收益分配权,也要有历史的耐心,充分尊重农户的乡土情结。     

震后交通管制下多出救点应急物资调运问题

销售季节性商品的零售企业在销售季节开始前通常仅能获得有限的市场信息,在销售过程中因滞销而产生剩余库存的现象十分普遍。因此,许多零售企业会将商品在一级市场销售之后以折扣价格在二级市场上继续销售。为此,建立了这一问题的两阶段模型,在较宽松的需求假设下分析了模型所具有的性质,通过求解得到了零售企业对季节性商品的订货量决策和商品在两级市场间转换时刻决策所要满足的最优条件。     

The role of social support when giving up drug abuse: a female perspective

This article contains a presentation and analysis of the results from two qualitative studies, which examined female drug abusers' everyday lives and the social support available to them within their close relationships. Both studies concerned women who were participating in work-training or treatment programmes and who were in the process of giving up drug abuse. The two main questions concerned the supply of social support from the women's social networks and whether the amount of support available or lack of support had any impact on the exit process. Social support within different relationships of the women's social networks is presented, as well as different types of professional social support and treatment. The results in relation to previous research about female drug abusers and social support from gender and class perspectives are discussed. Conclusions about three important factors when creating a new life after drug abuse are drawn.     

Now or Later?--Endogenous Timing of Threats

Whereas early threats are chosen before bargaining, late threats are determined after bargaining ended in conflict. Instead of exogenously imposing the timing of threats, these are derived endogenously as in indirect evolution or endogenous timing. Based on a duopoly market, we first derive the equilibrium for all possible constellations regarding the timing of threats. Our analysis surprisingly justifies the early timing of threats as suggested by Nash (1953).     

时间知觉的脑机制研究

当前时间知觉的脑机制的研究结果出现了定位论和非定位论的研究趋向。支持定位论的证据主要集中在小脑高级功能区运动计时特异化作用及基底神经节分泌的多巴胺对时间知觉的作用;支持非定位论的证据主要集中在脑损伤、脑成像研究中关于多个脑区整合作用机制以及多种神经递质在计时中的作用。上述两种趋向是基于时距长短不同所致,比如对秒以下计时加工的部位在小脑高级功能区,而加工1秒及以上的时距则涉及多个脑区及神经递质的整合作用。时间知觉之脑机制研究正方兴未艾。     

食品供应商不同时序的质量安全水平决策分析

食品供应商的生产决策对产品质量安全水平具有决定性作用。基于此,通过建立模型重点分析了单个供应商质量安全水平决策、两个供应商同时以及按照先后顺序进行质量安全水平的决策。分析结果表明:市场监管环境、产品价格的质量安全敏感度以及标准质量安全敏感度对供应商供给的产品质量安全水平、价格及利润具有直接影响;两个供应商决定供给高低质量安全水平产品时,其质量安全水平都低于单个供应商供给的标准质量安全水平。据此,为改善我国食品安全提出了对策。     

‘Escaping’ managed labour migration: worker exit as precarious migrant agency

ABSTRACT

This article narrows in on the mundane yet extraordinary events surrounding migrant farm workers’ decisions to leave their state-approved employment and to seek a better life in Canada outside of state-managed circulatory labour migration. In so doing, this research contributes to conceptualisations of precarity, and of precarious status in particular, that are beginning to recognise its effects not only on workers’ economic survival, but also the more ordinary daily conditions surrounding workers’ sense belonging and personal autonomy. In their refusal to accept the terms of their contractual circulatory labour migration agreements through what is conceptualised here as an act of ‘escape’, workers claim a space of belonging that contradicts the precarity of their formal citizenship status. In carving out a space in which they may perform autonomy and self-determination in daily life, however, this rejection of contingent citizenship status intensifies the precarious material conditions governing workers’ relationship to the state.     

超竞争环境下企业困境并购定价与时机研究

在超竞争环境下企业面临的竞争环境越来越动荡，企业的竞争优势呈现出短期性与临时性的特点，为了快速发展，越来越多的企业选择并购。本文以超竞争环境为研究背景，运用期权博弈理论，分析并建立了存在竞争对手的企业困境并购定价与时机选择模型，通过模型求解得到并购中主并企业给予目标企业的最优价值以及主并企业的最佳并购时机；此外，通过数值模拟重点分析了三个超竞争特征因子（竞争强度、竞争不确定性、企业价值损失因子）、企业困境因子以及竞争对手的溢价水平对企业困境并购时机的影响。本文研究发现：（1）被并企业得到的价值补偿比例及主并企业最佳并购时机均受到各超竞争特征因子、企业困境因子以及竞争对手溢价水平的综合影响；（2）竞争对手的存在会使目标企业得到的价值补偿比例增加；（3）超竞争环境下企业困境并购中主并企业的最佳并购时机取决于并购双方的相对价值比；（4）随着可能导致双方谈判破裂因素、事件的增多以及企业财务困境程度的增加，主并企业提前进行并购的可能性增加；（5）随着竞争强度、竞争不确定性、竞争对手造成溢价水平的增加，主并企业推迟并购时机的可能性增大。