铜合金挤压材常见缺陷分析及预防

分析了铜合金挤压材常见缺陷(裂纹、气泡、过热、过烧、划伤、扭拧、缩尾、偏心、尺寸超差等)的产生原因,提出了相应的预防措施.生产实践表明,采取这些措施后,有效地改善了产品质量,取得了良好的经济效益.     

ICP—AES测定锌合金中杂质元素含量的研究

研究了用ICP-AES法测定锌合金中杂质元素铝、镉、铁、镁、铅、铜的方法，建立了最佳工作条件，测定了方法的检出限、测定下限。进行了干扰试验、回收率试验、基体效应等试验，本方法简便、快速、准确，结果令人满意。     

Access数据库在采购管理中的应用

介绍了Access数据库的特点和优点,在采购管理中应用的意义.使用Access编写了<供应仓储管理系统>,论述了该系统的设计思想、程序结构及应用效果.该系统的应用,减轻了工作人员劳动强度、提高了工作效率、确保了物资及时供应、减少了资金的占压.     

抓斗吊车常见故障与解决措施

分析了20 t桥式抓斗起重吊车常见故障及原因,采取了相应的解决措施,从根本上杜绝了吊车的常见故障、节约了备件、降低了生产成本、减轻了维修人员劳动强度及提高了企业的经济效益.     

天钢技术创新回顾与展望

回顾了近年来天津钢铁集团有限公司技术创新的发展和所取得的成就。重点介绍了技术创新体系建设、工艺技术创新、产品研发、产学研合作、知识产权战略、标准制修订、信息化建设等方面的技术创新现状,阐述了产品质量保障、品牌建设以及绿色发展情况,并指出了未来技术创新的发展方向。     

Incoloy 825耐蚀合金

介绍了Incloy 825合金的化学成分及各元素的作用，给出了Incoloy 825合金的物理性能、机械性能、耐蚀性能，给出了Incoloy 825合金的组织，叙述了Incoloy 825合金的热处理、冷热加工、机加工、焊接工艺，列出了合金的适用技术条件、产品形状和用途。     

铜合金挤压材常见缺陷分析及预防措施

分析了铜合金挤压材常见缺陷（裂纹、气泡、过热、过烧、划伤、扭拧、缩尾、偏心、尺寸超差等）的产生原因，提出了相应的预防措施。生产实践表明，采取这些措施后，有效地改善了产品质量，取得了良好的经济效益。     

贵金属配合物在医药领域中的应用

简要综述了贵金属抗癌配合物的发现、临床应用、抗癌机理及研究现状,着重介绍了11类铂配合物的最新研究进展,指出了应用中尚须解决的问题,并展望了铂、金、银、锇、钌、铑、钯、铱等贵金属配合物在医药领域的应用前景。     

伴生碲资源回收提取与高纯碲生产

碲是重要稀散金属和半导体材料,国内外对其提取和提纯进行了大量研究。文章首先对碲的矿物形成、伴生情况、资源赋存和生产消费情况进行了介绍,明确了主要工业生产原料为铜铅阳极泥;其后,对碲的提取工艺进行了概述,详细介绍了硫酸化法、氧化焙烧-碱浸法、氧压浸煮法、苏打法的方法原理和主要流程;最后对高纯碲的主要制备工艺进行了概述,对其除杂、电解、蒸馏、氢化以及区域熔炼工序进行了介绍,分析了6N以上纯度碲的生产方法。     

某黄金冶炼厂黄金精炼工艺的优化改进

针对某黄金精炼厂原化学-溶剂萃取金精炼过程存在反应速度慢、金的浸出效果差、萃取剂价格高、生产周期长、大气污染、安全隐患等问题,提出控电除杂、合质金粉化、水溶液氯化、粗银粉电解精炼、增加真空过滤等措施对其进行优化。优化改进后,简化了工艺流程,降低了生产成本,提高了金的回收率,缩短了生产周期,预防了氮氧化物对空气的污染,消除了安全隐患,保证了产品质量。     

基于粗糙商集的模糊隶属度集值统计算法

模糊隶属度无统一算法,定义存在分歧.根据模糊概念"内涵明确,外延不明确"的特点,定义隶属度为不同外延对内涵的从属程度.在信息系统中,概念的外延用对象表示,内涵由属性表示,由此提出了求解隶属度的新算法:由原始统计数据组成初始信息系统,用粗糙集理论求得其商集并构建集值信息系统;该集值信息系统对应的条件概率空间中的条件概率即为隶属度.广义上信息系统可分为信息系统(无决策属性)和目标信息系统(有决策属性)两类.隶属度也可分为两类:第一类外延对象为内涵属性本身值,如年龄对青年人的隶属度(信息系统);第二类外延对象为不同于内涵属性的另一属性值,如边坡工程安全系数对稳定状态的隶属度(目标信息系统).计算以上两个实例,前者与已有结论作对比验证,后者与函数选择、经典统计方法及贝叶斯公理作对比验证,可知结果可靠,算法可行.      

Sex differences in romantic love attitudes among college students

Collection and collation of statistical information is an ever-increasing requirement in the modern medical illustration department. Business planning and general management decisions are all based on such criteria. As the NHS 'market place' philosophy evolves, traditional manual systems of record-keeping are no longer adequate. This paper describes the 'in-house' development of a customized database using the Apple Macintosh computer, and outlines the reasons for this choice of system.     

Towards improved information retrieval from medical sources

We review a HEALNet health informatics project directed at information extraction from medical text resources in support of evidence based practice (EBP). The motivation for the approach is summarized. A brief review of pertinent methodology is given and the rationale for exploring approaches to statistical concept representation (SCR) derived. Data on the qualitative comparison of five related systems are presented. Installation and tests of three of these systems revealed that systems designed to deal with literature are not able to handle medical record text adequately because of various idiosyncrasies of the latter. To overcome these, it is necessary to control the system's text manipulation algorithms. This prompted us to build our own system. The principles of this development and its results are summarized. They include the construction of a core information retrieval (IR) system, which is now operational, initiation of work on the collection of test data bases and development of a conceptual framework for comprehensive system evaluation. A brief outline of further steps concludes the presentation.     

What Information Can or Cannot Be Exchanged?

What information can or cannot be exchanged between different systems? Since the dawn of the computer-aided design and engineering era, interoperability has been an issue. The exchangeable set of information between different systems has been loosely defined as the intersection of information. Yet, as information flow has directionality, a general definition of “intersection” is inadequate to define an exchangeable set of information. This paper proposes a new directive set operation, semantic intersection, and discusses which information can or cannot be exchanged between different systems using the concept of semantic intersection. This opens up the possibility of predetermining or calculating the exchangeable set of information between two or more systems or the possibility of automated generation of a standard product model between different systems. This paper focuses on data exchange between systems, but the proposed theory is also applicable to data exchange between human beings.     

Construction of composite scales for risk assessment in epidemiology: an application to ectopic pregnancy

Composite scoring systems that combine information contained in a number of risk factors are being used increasingly in clinical practice, planning, and health risk appraisal. The authors propose a methodological framework for the construction and validation of a composite measurement scale to assess the risk, considered as a continuous phenomenon, of developing a particular disease or outcome. This framework integrates several statistical methods, especially those concerning model fitting, coefficient rounding, and validation strategy. It also uses psychometric methods, addressing important measurement properties such as measurement level, content and construct validity, and reliability of the constructed scale. The proposed framework is illustrated by application to the construction of a composite scale for measurement of the risk of ectopic pregnancy.     

SERC—A Model for Estimating Construction Inputs

One of the main problems in the process of design and management of construction projects is obtaining accurate information for preliminary estimates. This information is crucial for the development of integrated systems for construction management because of the relationship between construction input data and subjects such as estimating, cost control, scheduling, resource management, etc. Existing methods for estimating input that originated in industrial engineering are inadequate for the unique conditions of the construction industry. The model described in this paper applies statistical analysis of data from past projects, and enables the user to estimate the data needed for the construction of a new project. The model is based on the following components: Project items and their quantities; inputs needed to produce those items; and factors that affect inputs of a specific project. The model equation was calculated using multiple regression techniques. The paper concludes with a case study of a construction input configuration for a concrete structure.     

Exploratory Study on Value of Information Systems to Electrical Construction Companies: Resource-Based View

Many practitioners and researchers believe that the application of information systems in the construction industry lags behind that of other industries such as the manufacturing industry, because the construction industry is mainly composed of small to medium size companies. Besides, to many people, the value of information systems to their business is vague and elusive. Existing studies on the value of information systems are not specifically focused on small to medium size specialty contractors such as electrical contractors. In addition, with an intention to demonstrate the value of information systems to the improvement of operations or business of all relevant companies, those studies typically do not look into the impact of information systems on the competitive advantage of individual companies. This paper argues that such a generalization of the value of information systems, although valuable to both practitioners and researchers, may have overlooked the fact that the value of information systems needs to be reflected through improved competitive advantage of a company and the competitive advantage is company specific. Thus, the examination of different effects of information systems on individual companies can generate useful insight into the value of information systems because such a strategy leads to a better understanding of the relationships between information systems and the competitive advantage of individual companies. With such a perspective, this study applies a case study strategy to study five small to medium size electrical construction companies based on the resource-based view theory. The case studies show that the observed electrical construction companies are well equipped in terms of physical information infrastructure in relation to their business objectives regardless of company size. However, their capabilities of strategically integrating information systems with their business plans and with their external business partners are general lacking, compared with their physical information system infrastructure. This is partly because many electrical contractors do not fully understand that there are many different forms of information systems that have different impacts on gaining and sustaining competitive advantage. This paper then conjectures that the existing imbalanced application of information systems may not lead to the improved competitive advantage of electrical construction companies, which in turn prevent many contractors from clearly seeing the value of the information systems. Thus, the paper further points out that a plan for the systematical implementation of information systems in a company is very important. However, the successful development of such a plan depends on a better understanding of electrical contactors on the concepts of information system capabilities, competitive advantage, and their relationships.     

The composition of individual molecular species of plasma phosphatidylcholine in human pregnancy

The role of medical informatics in telemedicine is dependent on using the power of the computerized database to not only feed patient specific information to the health care providers, but to use the epidemiological and statistical information in the data base to improve decision making and ultimately care. The computer is also a powerful tool to facilitate standardizing and monitoring of care and when applied in continuous quality improvement methodology it can enhance the improvement process well beyond what can be done by hand. The coupling of medical informatics with telemedicine allows sophisticated medical informatics systems to be applied in low population density and remote areas.     

Model Induction with Support Vector Machines: Introduction and Applications

The rapid advance in information processing systems in recent decades had directed engineering research towards the development of intelligent systems that can evolve models of natural phenomena automatically—“by themselves,” so to speak. In this respect, a wide range of machine learning techniques like decision trees, artificial neural networks (ANNs), Bayesian methods, fuzzy-rule based systems, and evolutionary algorithms have been successfully applied to model different civil engineering systems. In this study, the possibility of using yet another machine learning paradigm that is firmly based on the theory of statistical learning, namely that of the support vector machine (SVM), is investigated. An interesting property of this approach is that it is an approximate implementation of a structural risk minimization (SRM) induction principle that aims at minimizing a bound on the generalization error of a model, rather than minimizing only the mean square error over the data set. In this paper, the basic ideas underlying statistical learning theory and SVM are reviewed, and the potential of the SVM for feature classification and multiple regression (modeling) problems is demonstrated by applying the method to two different cases of model induction from empirical data. The relative performance of the SVM is then analyzed by comparing its results with that of ANNs on the same data sets.     

Vector reconstruction from firing rates

In a number of systems including wind detection in the cricket, visual motion perception and coding of arm movement direction in the monkey and place cell response to position in the rat hippocampus, firing rates in a population of tuned neurons are correlated with a vector quantity. We examine and compare several methods that allow the coded vector to be reconstructed from measured firing rates. In cases where the neuronal tuning curves resemble cosines, linear reconstruction methods work as well as more complex statistical methods requiring more detailed information about the responses of the coding neurons. We present a new linear method, the optimal linear estimator (OLE), that on average provides the best possible linear reconstruction. This method is compared with the more familiar vector method and shown to produce more accurate reconstructions using far fewer recorded neurons.