高精度渗碳控制方法

在采用电阻法直接测控碳势的方法中,提出了一种分段参数调节增量式PID算法,通过实际调试和理论推导表明,渗碳工艺过程控制具有控制超调量小、过渡时间短、精度高、软件实现方便等优点,稳定后碳势控制精度可达±0.03%。     

论行政自由裁量权的法律控制

行政自由裁量权是行政机关拥有的一种行政权 ,在我国运用范围较为广泛 ,且有其合理存在的依据。但是 ,由于诸多方面的原因 ,又常常导致行政自由裁量权的滥用 ,为了实现依法行政 ,必须对行政自由裁量权进行控制     

Dose-Response and Risk Assessment of Airborne Hexavalent Chromium and Lung Cancer Mortality

This study evaluates the dose-response relationship for inhalation exposure to hexavalent chromium [Cr(VI)] and lung cancer mortality for workers of a chromate production facility, and provides estimates of the carcinogenic potency. The data were analyzed using relative risk and additive risk dose-response models implemented with both Poisson and Cox regression. Potential confounding by birth cohort and smoking prevalence were also assessed. Lifetime cumulative exposure and highest monthly exposure were the dose metrics evaluated. The estimated lifetime additional risk of lung cancer mortality associated with 45 years of occupational exposure to 1 microg/m3 Cr(VI) (occupational exposure unit risk) was 0.00205 (90%CI: 0.00134, 0.00291) for the relative risk model and 0.00216 (90%CI: 0.00143, 0.00302) for the additive risk model assuming a linear dose response for cumulative exposure with a five-year lag. Extrapolating these findings to a continuous (e.g., environmental) exposure scenario yielded an environmental unit risk of 0.00978 (90%CI: 0.00640, 0.0138) for the relative risk model [e.g., a cancer slope factor of 34 (mg/kg-day)-1] and 0.0125 (90%CI: 0.00833, 0.0175) for the additive risk model. The relative risk model is preferred because it is more consistent with the expected trend for lung cancer risk with age. Based on statistical tests for exposure-related trend, there was no statistically significant increased lung cancer risk below lifetime cumulative occupational exposures of 1.0 mg-yr/m3, and no excess risk for workers whose highest average monthly exposure did not exceed the current Permissible Exposure Limit (52 microg/m3). It is acknowledged that this study had limited power to detect increases at these low exposure levels. These cancer potency estimates are comparable to those developed by U.S. regulatory agencies and should be useful for assessing the potential cancer hazard associated with inhaled Cr(VI).     

Valuation of childhood risk reduction: the importance of age, risk preferences, and perspective.

This article explores two problems analysts face in determining how to estimate values for children's health and safety risk reductions. The first addresses the question: Do willingness‐to‐pay estimates for health risk changes differ across children and adults and, if so, how? To answer this question, the article first examines the potential effects of age and risk preferences on willingness to pay. A summary of the literature reporting empirical evidence of differences between willingness to pay for adult health and safety risk reductions and willingness to pay for health and safety risk reductions in children is also provided. The second dimension of the problem is a more fundamental issue: Whose perspective is relevant when valuing children's health effects—society's, children's, adults‐as‐children, or parents'? Each perspective is considered, followed ultimately by the conclusion that adopting a parental perspective through an intrahousehold allocation model seems closest to meeting the needs of the estimation problem at hand. A policy example in which the choice of perspective affects the outcome of a regulatory benefit‐cost analysis rounds out the article and emphasizes the importance of perspective.     

试论企业内部控制制度的建立与完善

企业内部控制制度是法人治理结构的重要组成部分,有效地执行健全的内部控制制度是实现企业目标的有力保障,而企业目标的实现又能促使企业更加注重内部控制制度。企业环境、企业文化和企业高层执行内部控制制度的状况是建立和完善企业内部控制制度的关键。     

微服私访:作为一种社会控制的官方民间法

无论在中国古代还是当下,微服私访现象都较为常见。微服私访是决策者借助被访者的信任,为夺回真实信息控制权所做的一种个人努力,是一种实现非正式社会控制的官方民间法。     

对降低中国农业生产风险的方式探讨

农业生产领域因其要受气候条件、自然灾害、技术的改变、信息的不完全、国家政策的变动,有着不同于其他行业的特殊风险性,而我国农户大多又是风险规避者,所以,如何降低农业生产中的风险,及如何看待降低风险的方式在中国的实效性问题,成为目前解决“三农”问题关键所在。     

对工程造价控制管理问题的探讨

分析我国工程造价管理中存在的问题;从工程建设全过程出发,论述如何控制工程造价。     

对社会主义市场经济内涵的理论思考

自我国确立社会主义市场经济体制改革目标以来,市场经济得到迅速发展,市场活动有序进行,但也存在不少问题。因此,全面准确地把握社会主义市场经济的内涵,对于我们完善社会主义市场经济体制,建立规范的市场经济秩序、实现经济的平稳运行有着重要的意义。     

行政自由裁量权的两面性及其控制路径

行政自由裁量权作为行政权的重要组成部分,在行政活动中扮演着独特的角色。随着社会事务的日益纷繁复杂,行政自由裁量权在大幅度膨胀的同时,也给人们的正当权益造成了威胁。因此应考察其存在的合理性和被滥用的可能性,从外部控制和行政自我控制等视角对其有效控制路径作出研析。