LONWORKS现场总线质量控制技术在油田生产中的应用

现场总线是一种安装在生产过程区域的现场设备或过程仪表和控制室内的自动化控制系统之间的开放式、数字化、双向串行、多节点的数据通信总线。该技术是近年来随着计算机、通信、控制技术的进步，数字通信网络应用到工业过程现场控制后，逐渐发展．并得到广泛应用的现代控制技术，目前，比较有名的有FF、Profibus、LONWORKS、HART、CAN等总线。     

解读新一轮改革的逻辑

"十八大"以后,中国进入新一轮改革时期。新一轮改革是一场问题导向式改革,新时期所出现的诸如经济增长乏力、效率低下、市场秩序混乱等新问题是新一轮改革的逻辑起点,放、激、管三管齐下是解决新问题的主要方式。新一轮改革的目标是处理好政府与市场的关系,而理顺政府与市场关系的关键在于充分发挥市场在资源配置中的决定性作用,通过市场发力形成中国经济增长的内生力,探索出一条具有中国特色的市场经济道路,这条道路就是中国模式。     

Multi-product capacitated facility location problem with general production and building costs

This research introduces the multi-product capacitated facility location problem with general production and building costs (MP-CFLPGC). The MP-CFLPGC extends previous problems found in the literature by including multiple products and general production and building cost functions that allow the modeling of different behaviors like economies of scale and congestion. The MP-CFLPGC is formulated as a mixed integer linear program (MILP). To evaluate the performance of the proposed formulation we analyze the results of a commercial optimizer on a set of 288 randomly generated test instances that resemble the Colombian cement industry supply chain. After one hour the optimizer achieved an optimality gap of 1.0 % or less in 55 % out of the 288 test instances. On average the optimality gap was 3.57 %. Additionally, we propose a randomized mathematical-programming-based heuristic for the test instances where the MILP formulation presents significantly high optimality gaps.     

Inflation targeting credibility and sovereign risk: evidence from Colombia

This article relates to the literature on sovereign risk in developing countries. In particular, we present empirical evidence to address the effect of inflation targeting credibility on sovereign risk based on the Colombian experience. The findings denote that credibility is an important improvement in the institutional framework to reduce the sovereign risk premium.     

The relationship between high performance work systems and employee proactive behaviour: role breadth self‐efficacy and flexible role orientation as mediating mechanisms

Drawing on the contextual perspective, this study provides novel empirical evidence on how the organisational context (specifically, the firm's human resource strategy) has an effect on employee proactivity. We use matched data from managers and employees in 102 Spanish professional service firms to examine how high performance work systems contribute to enhance employee proactive behaviours through two motivational variables: role breadth self‐efficacy and flexible role orientation. Results of a multilevel study demonstrate that role breadth self‐efficacy mediates between HPWS and employee proactivity, but flexible role orientation does not mediate this relationship.     

粮食中镉含量测定方法初探:以石墨炉原子吸收分光光度计法为例

笔者长期从事粮食中镉污染检验工作,大量实践经验表明,虽然原子吸收仪的品牌、型号各不相同,但应用原理、结构大致相同。本文以石墨炉原子吸收分光光度计法对粮食中镉的含量的检测为例进行说明,发现试样前处理、试剂空白、使用试剂、回收实验及在操作过程中的对仪器的处理等对检测结果均会产生直接影响。为确保检测结果准确性,本文对检测过程中影响检测结果的各注意事项进行了分析总结,希望能对从事镉污染检测工作的人员提供理论指导和借鉴。     

Essential equilibria of large generalized games

We characterize the essential stability of games with a continuum of players, where strategy profiles may affect objective functions and admissible strategies. Taking into account the perturbations defined by a continuous mapping from a complete metric space of parameters to the space of continuous games, we prove that essential stability is a generic property and every game has a stable subset of equilibria. These results are extended to discontinuous large generalized games assuming that only payoff functions are subject to perturbations. We apply our results in an electoral game with a continuum of Cournot-Nash equilibria, where the unique essential equilibrium is that only politically engaged players participate in the electoral process. In addition, employing our results for discontinuous games, we determine the stability properties of competitive prices in large economies.     

Global financial crisis and dependence risk analysis of sector portfolios: a vine copula approach

We use regular vine (r-vine), canonical vine (c-vine) and drawable vine (d-vine) copulas to examine the dependence risk characteristics of three 20-stock portfolios from the retail, manufacturing and gold-mining equity sectors of the Australian market in periods before, during and after the 2008–2009 global financial crisis (GFC). Our results indicate that the retail portfolio is less risky than the manufacturing counterpart in the crisis period, while the gold-mining portfolio is less risky than both the retail and manufacturing sector portfolios. Both the retail and gold stocks display a higher propensity to yield positively skewed returns in the crisis periods, contrary to the manufacturing stocks. The r-vine is found to best capture the multivariate dependence structure of the stocks in the retail and gold-mining portfolios, while the d-vine does it for the manufacturing stock portfolio. These findings could be used to develop dependence risk- and investment risk-adjusted strategies for investment, rebalancing and hedging which more adequately account for the downside risk in various market conditions.