尾砂胶结充填新工艺在武山铜矿的研究与应用

为满足技改需求,扩大生产能力,武山铜矿的二期扩产设计采用下向分级尾砂胶结充填新工艺试验研究,通过研究改进胶结充填工艺过程、取消钢筋混凝土人工假底、扩大回采断面来扩大生产规模,提高工作效率。     

The mechanisms of project management of software development

The changing environments of software development such as component-based, distributed and outsourced software development require matching changes by project managers to monitor, control and coordinate their projects. While the objectives of project management may be well established, the mechanisms with which those objectives are achieved are less well known. An empirical study was undertaken to investigate which mechanisms were used by practising project managers to monitor, control and coordinate software development projects.First, the types of mechanisms are discussed so that the mechanisms can be classified usefully. Then, the design of the empirical study is described. The data were collected through structured interview, which provided both quantitative and qualitative data. The data are analysed for each mechanism separately and the findings presented. The study found that project managers use multiple mechanisms to achieve project management objectives and use the same mechanism to serve multiple objectives. Further research is suggested to investigate project management from the opposite orientation, that is, which objectives are served by specific project management mechanisms.     

A Bayesian propensity score adjustment for latent variable modeling and MCMC algorithm

The estimation of the differences among groups in observational studies is frequently inaccurate owing to a bias caused by differences in the distributions of covariates. In order to estimate the average treatment effects when the treatment variable is binary, Rosenbaum and Rubin [1983. The central role of the propensity score in observational studies for causal effects. Biometrika 70, 41-55] proposed an adjustment method for pre-treatment variables using propensity scores. Imbens [2000. The role of the propensity score in estimating dose-response functions. Biometrika 87, 706-710] extended the propensity score methodology for estimation of average treatment effects with multivalued treatments.However, these studies focused only on estimating the marginal mean structure. In many substantive sciences such as the biological and social sciences, a general estimation method is required to deal with more complex analyses other than regression, such as testing group differences on latent variables. For latent variable models, the EM algorithm or the traditional Monte Carlo methods are necessary. However, in propensity score adjustment, these methods cannot be used because the full distribution is not specified.In this paper, we propose a quasi-Bayesian estimation method for general parametric models that integrate out the distributions of covariates using propensity scores. Although the proposed Bayes estimates are shown to be consistent, they can be calculated by existing Markov chain Monte Carlo methods such as Gibbs sampler. The proposed method is useful to estimate parameters in latent variable models, while the previous methods were unable to provide valid estimates for complex models such as latent variable models.We also illustrated the procedure using the data obtained from the US National Longitudinal Survey of Children and Youth (NLSY1979-2002) for estimating the effect of maternal smoking during pregnancy on the development of the child's cognitive functioning.     

Credibility and applicability of virtual reality models in design and construction

In this paper, we present the findings from an extensive study of the use of virtual reality (VR) models in large construction projects. The study includes two parts: The first part presents a quantitative questionnaire designed to investigate how VR models are experienced and assessed by the workforce at a building site. The second part includes a qualitative field survey of how VR models can be applied and accepted by professionals in the design and planning process of a large pelletizing plant. Through mainly studying persons who had little or no experience with advanced information technology (IT), we hoped to reveal the attitudes of the average person working at a construction site rather than of an IT expert. In summary, the study shows that the VR models in both projects have been very useful and well accepted by the users. Today’s information flow is, from a general point of view, considered to be insufficient and the hypothesis is that using VR models in the construction process have the potential to minimize waste of resources and improve the final result.     

钢—混凝土组合梁的试验研究

首次提出以早强混凝土外包U型薄钢板的新型组合梁,并以9根梁2天龄期的试验为基础,对组合梁的工作性能进行了分析研究。     

Finite element analysis of steel-concrete-steel sandwich beams

The static behaviour of Bi-Steel beams was simulated using a finite element model. The model was compared to test results showing good agreement. It was then used in parametric studies of transverse shear capacity and uniformly distributed load cases of Bi-Steel beams. It was possible to isolate the transverse shear failure mode and prevent other failure modes from using the FE model. This enabled the comparison and verification of the proposed design equations for transverse shear. Based on parametric studies, modifications to the design method were also proposed to accommodate udl cases.     

Influence of gender,program of study and PC experience on unethical computer using behaviors of Turkish undergraduate students

This study administered the unethical computer using behavior scale (UECUBS) developed by [Namlu, A.G., & Odabasi, F. (2007). Unethical computer using behavior scale: A study of reliability and validity on Turkish university students. Computers and Education, 48, 205–215.] to investigate whether gender, program of study and PC experience have an impact on ethical judgments of undergraduate students regarding information and communication technologies (ICTs). The sample consisted of 559 undergraduates from the Education Faculty of the most populated state university in Turkey. The results of 5 (program of study) × 2 (gender) × 2 (PC experience) between-groups analysis of variance (ANOVA) indicated no significant differences among different programs of study and between high and low experienced PC users. The analysis showed significant differences between males and females. A significant interaction between the program of study and gender was found, which indicated that the difference between males and females did not follow a similar pattern across different programs of study. More specifically, females’ ethical judgments were consistent across different fields while males’ judgments varied according to the field of study.     

ERP and SCM systems integration: The case of a valve manufacturer in China

Many modern organizations integrate enterprise resource planning (ERP) and supply chain management (SCM) systems, as they work in a complementary fashion. This often results in technical and organizational challenges. Neway, a Chinese organization, recently went through this complex process. This required efficient procurement and management of hardware, software, and human resources for successful completion. The integrated system was found to improve operations, foster a paperless environment, and provide efficient inventory tracking and picking. It also had several tangible benefits, including reduced lead time and improved inventory accuracy. ERP and SCM systems integration is still a novel concept for a Chinese manufacturing organization. Our case study details the organization's experience, identifies challenges that were faced, and describes solutions adopted to overcome them.     

Inhibited and aggressive preschool children at 23 years of age: Personality and social transitions into adulthood.

In a 19-year longitudinal study, the 15% most inhibited and the 15% most aggressive children at ages 4-6 years were followed up until age 23 years and were compared with controls who were below average in preschool inhibition or aggressiveness. As adults, inhibited boys and girls were judged as inhibited by their parents and showed a delay in establishing a first stable partnership and finding a first full-time job. However, only the upper 8% in terms of inhibition tended to show internalizing problems, including self-rated inhibition. Aggressive boys showed an externalizing personality profile in the parental and self-judgments, were educational and occupational underachievers, and showed a higher adult delinquency rate than the controls, even after sex and socioeconomic status were controlled. The results suggest delayed social transitions without internalizing problems for most male and female inhibited children and a significant long-term risk of an externalizing profile for aggressive children. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

基于比较优势的我国军工企业绩效评价方法研究

考虑了集团下属企业的比较优势特征,提出了一种基于比较优势特征的企业绩效评价方法,并以新光集团所属10家军工企业为样本进行了实证研究.从实证研究结果看,在选取的10家下属企业中,有一半以上具备比较优势,通过绩效评价得到的相关分析结果可为集团及相关部门提供决策支持.