基于产品寿命周期的质量成本模型及其分析

传统的质量成本数学模型通常是根据产品的合格率即产品的质量水平来建模的,无法反映产品质量成本与产品寿命之间的相互关系。本文根据产品所处寿命周期各个阶段质量成本的变化特性,建立产品在整个寿命周期的质量成本数学模型,即产品质量成本随产品寿命随机变量变化的函数关系;提出了尽量缩短产品介绍期时间,在产品成长期推行零缺陷的质量管理要求及设法延长产品成熟期时间的优化设计原则。     

Distribution of cost inefficiency in stochastic frontier approach: evidence from Spanish banking

The aim of the paper is to demonstrate the appropriateness of an a priori analysis to determine the distributional assumption of the inefficiency term in a stochastic frontier model. To this end, theoretical distributions of estimated inefficiency were obtained when the inefficiency term is assumed to be distributed as a half normal and an exponential in a cost frontier model. Comparisons of such theoretical distributions with the respective cost inefficiency estimators using the goodness of fit test allow selecting the most appropriate distributional assumption. The application on three data sets of Spanish banking system in 2009 demonstrated the relevance of the research question. First, the results of estimated cost inefficiency with a half normal assumption are larger than with an exponential distribution significantly. Besides, half normal assumption was rejected and exponential was not rejected as the most appropriate distribution of inefficiency term in Spanish banking data set. However, the adjustment of saving banks data had been better with the former distribution than the latter. In the case of banks, any distribution results appropriate. To sum up, this work demonstrate that the distributional assumption on inefficiency term in Stochastic Frontier Approach must be established in a justified way, as it can significantly bias the results of estimated inefficiency and therefore, influences improving policies and strategies in the Spanish banking sector.     

Fathering attitudes and behaviors among low-income fathers

ABSTRACT

This study evaluated the effectiveness of a fatherhood intervention designed to improve the fathering attitudes and behaviors of fathers who are low income from metropolitan and rural communities in Louisiana. The study was successful in recruiting a sample of predominantly African American fathers (N = 57) and retaining the participants over time. An adequate number of fathers achieved the intervention goals to obtain employment, increase their earnings, and complete educational (i.e., Graduate Equivalency Diploma [GED]) training. In addition, after having completed the program, there was a statistically significant improvement in fathers’ relationship with the mothers of their children. Additionally, there were increases in fathers’ positive attitudes about being a father, perceived closeness with their children, amount of contact with their children, and satisfaction with the amount of time spent with their children; however, none of these differences were statistically significant. Most of the fathers gave favorable reports regarding the fatherhood program’s goals and delivery.     

新型交联酸液体系的研制及其应用

针对滩坝砂低渗透油藏渗透率低、储量规模大、储层物性差、非均质严重、层间差异大等地质特点，研制了新型地面交联酸液体系，通过室内交联和破胶实验，筛选出了能在强酸性条件下交联，成本较低的稠化剂和交联剂，并配制了交联酸进行室温成胶和破胶实验，确定了室内最优的交联比和聚合物黏度，加入添加剂配制成交联酸体系，分别进行成胶、破胶、缓蚀、助排、耐温实验。新型地面交联酸液体系具有高黏度、低滤失，低酸岩反应速度，更大改造半径等优点，在滨10X1 井应用取得良好增产效果。     

Optimum design-based ratio estimators of the distribution function

The ratio method is commonly used to the estimation of means and totals. This method was extended to the problem of estimating the distribution function. An alternative ratio estimator of the distribution function is defined. A result that compares the variances of the aforementioned ratio estimators is used to define optimum design-based ratio estimators of the distribution function. Different empirical results indicate that the optimum ratio estimators can be more efficient than alternative ratio estimators. In addition, we show by simulations that alternative ratio estimators can have large biases, whereas biases of the optimum ratio estimators are negligible in this situation.     

Regional coordination of European environmental policies

Over the last years the European Union (EU) has implemented ambitious climate and energy targets for 2020, i.e. the 2020 Climate and Energy Package (Package), to become a highly efficient, low carbon economy. The Package assigns binding renewable energy sources (RES) target for each EU member countries. Indeed costs to reach Package's targets vary among EU countries, given heterogeneity among regions and different instruments implemented to spur RES deployment. The aim of our paper is to provide a policy tool for EU policy makers in the negotiation process that assigns achievable quantitative targets according to which countries are not inclined to deviate from the agreement.We compute potential extra costs that may arise when some EU countries fail to reach the assigned objective within the Package with reference to RES target. More generally, our simulation model is an instrument that allows EU policy makers to assess incentives that countries might have to participate or not to the environmental agreements. Our analysis shows that partial participation to the Package produces inefficiencies by rising costs for other participating countries to the environmental agreement. Finally, we propose a new policy mechanism based on progressive sanctions for countries that do not meet their national targets, which are proportional to the monetary value of the penalty they impose to the rest of the EU countries with their opportunistic behavior.     

低碳背景下促进我国页岩气产业化的对策研究

随着能源安全和二氧化碳减排指标的日益控制，加大天然气资源开发力度、大规模清洁能源替代将是推动中国节能减排、低碳发展的最现实途径之一。以页岩气、煤层气为主的非常规天然气凭借其资源量大和碳排放量低的优势，必将伴随着低碳发展的大潮迎来新一轮开发利用高潮。从分析页岩气资源储存特点入手，归纳总结了美国促进页岩气产业发展的政策措施和技术发展模式，并对制约中国页岩气产业快速发展面临的配套政策、勘探开发理论、关键技术等3 方面的主要问题进行了深入分析。在此基础上，提出了推动中国页岩气产业快速发展应建立配套政策和加快技术创新的对策及建议。     

我国山地旅游地景区饭店能耗的影响因素

随着旅游业的兴起，旅游与能源的关系越来越紧张，威胁着旅游的可持续发展。从能源的角度进行分析，认为饭店规模、饭店海拔高度、各种能源成本、能源多样性、能源政策、山地主要旅游活动是影响山地旅游地景区饭店能耗的主要因素，并提出通过建立饭店能源管理体系、调整能源使用结构、提高木材等能源的利用效率、加强政府的宏观调控与能源引导消费、分散山地旅游季节分布、培养专业节能管理人才等措施，推进山地旅游地景区饭店的可持续发展。     

Setting Priorities in Behavioral Interventions: An Application to Reducing Phishing Risk

Phishing risk is a growing area of concern for corporations, governments, and individuals. Given the evidence that users vary widely in their vulnerability to phishing attacks, we demonstrate an approach for assessing the benefits and costs of interventions that target the most vulnerable users. Our approach uses Monte Carlo simulation to (1) identify which users were most vulnerable, in signal detection theory terms; (2) assess the proportion of system‐level risk attributable to the most vulnerable users; (3) estimate the monetary benefit and cost of behavioral interventions targeting different vulnerability levels; and (4) evaluate the sensitivity of these results to whether the attacks involve random or spear phishing. Using parameter estimates from previous research, we find that the most vulnerable users were less cautious and less able to distinguish between phishing and legitimate emails (positive response bias and low sensitivity, in signal detection theory terms). They also accounted for a large share of phishing risk for both random and spear phishing attacks. Under these conditions, our analysis estimates much greater net benefit for behavioral interventions that target these vulnerable users. Within the range of the model's assumptions, there was generally net benefit even for the least vulnerable users. However, the differences in the return on investment for interventions with users with different degrees of vulnerability indicate the importance of measuring that performance, and letting it guide interventions. This study suggests that interventions to reduce response bias, rather than to increase sensitivity, have greater net benefit.     

泡沫酸性能影响因素及其应用

针对应用常规酸化技术对低渗油层进行改造时,由于返排不彻底对其造成二次污染,故建议使用泡沫酸。并对其一些性能及其影响因素做了详细的介绍,列举了一些在现场的成功经验,以便进一步说明泡沫酸液的优越性能。