杭州汽轮机厂计算机集成制造系统——HTW-CIMS

本文介绍了杭州汽轮机厂计算机集成制造系统HTW-CIMS的总体方案以及开发和应用该系统时遵循的技术路线。     

Community-based household waste management: Lessons learnt from EXNORA's ‘zero waste management’ scheme in two South Indian cities

This paper presents two case studies on the efforts by a community-based organisation to promote a sustainable integrated waste management system in Indian mega cities. This effort was initiated in 1989 by a local non-governmental organisation (NGO) called EXNORA and is based on a ‘zero waste management scheme’ set up, run and financed by the residents themselves. As this model has been widely quoted as successful, the study aims at learning from two communities implementing this model.Results are reported from a survey of the two schemes that used various tools to assess both their performance and sustainability in selected residential areas of two Indian cities, Chennai and Hyderabad. The results indicate limited success of the schemes both in saving a significant fraction of the generated waste from dumping, and in rehabilitating the local poor. However, they show that motivated individuals can successfully set up and manage waste collection systems that lead to overall environmental improvements. The differences in the two schemes reflect how the local assets and contexts impact on the success of the scheme. The scheme in a rich neighbourhood of Hyderabad was less ambitious in its overall objectives and focussed on the provision of a waste management service, using the opportunity to provide local employment to a socially deprived fraction of the population. The scheme in a middle-class area of Chennai, although pioneering in its approach, suffered from diseconomies of scale and lack of social integration, making it less viable in the medium to long term. Both schemes suffered from a lack of community involvement, motivation and political support, which threatens the long-term sustainability of the enterprise. The research concludes that the role that communities can realistically play in management of their own waste depends on the local context. The system advocated by EXNORA seems to require significant local resources, and political and technical support which are hard to find and sustain without strong local leaders. Another model set up in the city of Visakhapatnam is finally introduced as an alternative. This is based on triangular contracts between the municipality, the residents and micro-enterprises and may provide a good solution in dealing with the technical and commercial aspects which communities find difficult.     

国产梁式引线器件平面集成混频器

介绍鳍线单平衡混频器电路的设计。混频器使用国产梁式引线混频二极管。混频器在31～37GHz的频率范围内,变频损耗小于10dB,最小值为7.2dB。     

氨基酸分析的新方法——积分脉冲安培检测-高效阴离子交换色谱法

介绍一种新型氨基酸分析方法——采用积分脉冲安培检测的高效阴离子交换色谱法(HPIC-IPAD) 对氨基酸的阴离子交换色谱分离和积分脉;中安培检测进行了较详细的讨论 对方法的应用做了简要介绍。该方法与其它方法比较,无须进行柱后或柱前衍生反应,对氨基酸可以直接进行分析,灵敏度较高 大多数氨基酸的检测限小于1pmol,线性范围可以达到3个数量级以上。     

An integrated model based on statistical process control and maintenance for two-stage dependent processes

The close relationship between quality and maintenance of manufacturing systems has contributed to the development of integrated models which use the concept of statistical process control (SPC) and maintenance. This article demonstrates the integration of the Shewhart individual-residual (Z_X ? Z_e) joint control chart and maintenance for two-stage dependent processes by jointly optimizing their policies to minimize the expected total costs associated with quality, maintenance and inspection. To evaluate the effectiveness of the proposed model, two stand-alone models—a maintenance model and an SPC model—are proposed. Then a numerical example is given to illustrate the application of the proposed integrated model. The results show that the integrated model outperforms the two stand-alone models with regard to the expected cost per unit time. Finally, a sensitivity analysis is conducted to develop insights into time parameters and cost parameters that influence the integration efforts.     

Whither practice-near research in the modernization programme? Policy blunders in children's services

In this article, we lament the effects of practice-distant research and associated policy initiatives on contemporary children's services in England. In the last decade, as a result of high profile inquiries into non-accidental child deaths, statutory children's social care services in the UK have been subject to a wide-reaching ‘modernization’ programme. We studied decision-making in the high blame environment of local authority children's services. Our research sought to examine the relationship between performance management and the impact of anticipated blame within the decision-making practices of those providing, supervising and managing these services. We show that systems and technologies can be developed which both assist the users in their daily work and achieve desired organizational goals, but without an ethnographically informed, practice-near approach, unsafe work regimes and practices can ensue.     

Analysis of Deviance for Hypothesis Testing in Generalized Partially Linear Models

In this study, we develop nonparametric analysis of deviance tools for generalized partially linear models based on local polynomial fitting. Assuming a canonical link, we propose expressions for both local and global analysis of deviance, which admit an additivity property that reduces to analysis of variance decompositions in the Gaussian case. Chi-square tests based on integrated likelihood functions are proposed to formally test whether the nonparametric term is significant. Simulation results are shown to illustrate the proposed chi-square tests and to compare them with an existing procedure based on penalized splines. The methodology is applied to German Bundesbank Federal Reserve data.     

Robust Inference for Near-Unit Root Processes with Time-Varying Error Variances

The autoregressive Cauchy estimator uses the sign of the first lag as instrumental variable (IV); under independent and identically distributed (i.i.d.) errors, the resulting IV t-type statistic is known to have a standard normal limiting distribution in the unit root case. With unconditional heteroskedasticity, the ordinary least squares (OLS) t statistic is affected in the unit root case; but the paper shows that, by using some nonlinear transformation behaving asymptotically like the sign as instrument, limiting normality of the IV t-type statistic is maintained when the series to be tested has no deterministic trends. Neither estimation of the so-called variance profile nor bootstrap procedures are required to this end. The Cauchy unit root test has power in the same 1/T neighborhoods as the usual unit root tests, also for a wide range of magnitudes for the initial value. It is furthermore shown to be competitive with other, bootstrap-based, robust tests. When the series exhibit a linear trend, however, the null distribution of the Cauchy test for a unit root becomes nonstandard, reminiscent of the Dickey-Fuller distribution. In this case, inference robust to nonstationary volatility is obtained via the wild bootstrap.     

Integrated nested Laplace approximation for the analysis of count data via the combined model: A simulation study

The combined model accounts for different forms of extra-variability and has traditionally been applied in the likelihood framework, or in the Bayesian setting via Markov chain Monte Carlo. In this article, integrated nested Laplace approximation is investigated as an alternative estimation method for the combined model for count data, and compared with the former estimation techniques. Longitudinal, spatial, and multi-hierarchical data scenarios are investigated in three case studies as well as a simulation study. As a conclusion, integrated nested Laplace approximation provides fast and precise estimation, while avoiding convergence problems often seen when using Markov chain Monte Carlo.