基于产品生命周期的汽车项目投资阶段识别模型

针对汽车产品投资的特殊不确定性和其投资数额大、分阶段投入的状况,应用产品生命周期理论判定汽车产品项目的投资阶段,进而获得准确的阶段投资决策点,据此构建了基于汽车产品生命周期的汽车产品投资阶段判定和汽车企业投资决策点识别模型,并就影响识别的因素、阶段、模型进行数学表述,就汽车产品投资决策点抉择问题提出了解决的思路和方法.     

种子产品不同生命周期对促销策略选择的影响

种子产品同其他产品一样，要经过市场导入期、成长期、成熟期，然后进入衰退期，文章论述了种子产品不同生命周期的市场特征，就不同时期应采取的促销措施发表了看法。     

种子产品不同生命周期对促销策略选择的影响

种子产品同其他产品一样，要经过市场导入期、成长期、成熟期，然后进入衰退期，文章论述了种子产品不同生命周期的市场特征，并就不同时期应采取的促销措施发表了看法。     

基于PLM系统的农机企业信息化技术应用探讨

0引言农业信息化是21世纪全球性农业潮流,是农业现代化的根本标志与重要保证。充分利用信息技术等高新技术发展现代化农业,已成为全球农业发展的热点与新的增长点。产品生命周期管理PLM(Product Lifecycle Management)是一种应用于单一地点的企业内部、分散在多个地点的企业内部,以及在产品研发领域具有协作关系的企业之间的,支持产品全生命周期的信息创建、管理、分发和应用的一系列应用解决方案,它能够集成与产品相关的人力资源,产品生命周期管理、流程、应     

产品生命周期中先行指标的分析

任何产品都有从研发上市到盛极而衰终至被市场淘汰的过程,我们企图用相关的财务指标预测产品生命周期,提前预知产品生命周期可能的演变方向,避免企业盲目投资、无序竞争,有效配置社会资源。     

锯材产品生命周期影响环境的评价方法与应用

在参阅国内外木材产品生命周期对环境影响评价方法的基础上,针对原木运输和锯材生产2段过程,结合对锯材产品生命周期评价中的环境特点,确定全球变暖、酸化、富营养化、烟尘、固体废弃物为主要的评价指标;从运输消耗和清单分析、选取影响环境类型、归类影响环境因子、计算影响环境负荷、影响环境潜值的加权标准化5个方面,构建评价模型;将实际生产中收集到的数据,应用到评价模型中计算。结果表明：在锯材产品生产中的5种影响环境评价指标中,全球变暖、酸化对环境的影响贡献值较大,其次是固体废弃物的污染、烟尘、粉尘、富营养化。提出了指导性建议,减少锯材生产对环境造成的危害。     

家具产品生命周期成本分析

以流水线生产的中密度三聚氰胺板家具为研究对象,采用生命周期成本分析的方法(LCCA),对家具产品的外部成本和内部成本进行评估。结果表明,影响三聚氰胺板家具产品生命周期成本的2个关键因素是三聚氰胺板的成本造价和能源的消耗量,其中提高能源的转化率是企业在保持一定利润的前提下,实现绿色生产的有效途径。     

农村公共产品供给满意的度评价研究

从农民非常需要的公共产品入手．构建农村公共产品供给的评价指标体系。根据指标体系的特点建立了相应的模糊综合评价模型．可以评价农村公共产品供给的满意度状况．从而提出相应的对策建议。     

分布式并发软件生命周期模型研究

针对软件开发原有生命周期模型主要针对传统的顺序集中式开发、已无法适应新的开发需要的问题，提出了针对分布式并发软件开发的菱形软件生命周期模型．分析了传统软件生命周期的缺点，给出了新的生命周期模型定义，以及模型组件的相互关系，分析了模型组件间的有效关系和无效关系，探讨了新模型如何弥补传统软件生命周期模型的不足．该模型定义清晰，使用简单，便于分析分布式并发软件的开发过程．     

客户生命周期价值模型扩展及在客户细分中的应用

在分析客户生命周期价值模型研究现状及模型参数变化影响的基础上，通过引入动态客户保持率及相关的客户生命周期时间，探讨了客户生命周期价值模型的扩展，并将扩展模型应用于企业客户细分，提出了基于客户价值的企业客户细分及客户关系管理策略。     

试论循环经济在《清洁生产促进法》中的法律地位

论述了《清洁生产促进法》出台的背景,以及清洁生产与循环经济的关系,指出循环经济在《清洁生产促进法》中明确的法律地位,提出了当前推动清洁生产、发展循环经济,在依法行政和法律的完善与配套方面的建议。     

生态产品评价系统在水产养殖机械设计中的应用

使用UML建模方法,开发了以综合评价为主的生态产品模糊评价系统。利用生态产品具有不同级别评价指标权重,对模糊层次分析法进行了改进,建立了改进的模糊层次分析法的系统评价模型;针对产品评价指标体系的复杂性,制定了具有一定通用性的、动态的且能反映综合评价要求的生态产品评价指标体系;将该系统应用到水产养殖领域,使养殖机械与养殖环境得到有机的结合,并以水产养殖用的鱼动式投饲机进行实例分析,对其各部件的属性进行评价,并对评价结果进行分析,寻求改善环境影响的机会。     

产品设计质量模糊评价及设计方案决策研究

提出了面向并行工程的基于功能特征的产品设计质量模糊评价及方案决策方法 ,将模糊综合评价与 AHP方法相结合 ,构造产品模糊综合决策模型。并以齿轮减速器为例 ,从众多的设计方案中选出最佳设计方案。     

基于XML的农产品质量追溯异构数据交换标准

我国农产品质量追溯信息系统建设还处于探索、试点阶段,没有形成最终的信息共享、交换标准,且由于农产品存在生产周期长、分布地域广、涉及的行业多、需要采集的信息复杂等特点,农产品全生命周期的质量安全监管很难由一个部门、一套系统来完成。因此不同部门、不同行业的质量追溯数据编码格式存在较大的差异,在全国层面上构建统一的农产品质量追溯数据库出现了屏障。根据农业部农产品质量追溯数据交换标准的实际研究工作,提出了一种基于XML的农产品质量追溯异构数据交换标准,从各采集点到省级监管平台、从省到国家,遵循统一的信息交换格式,从而实现信息资源共享和信息资源利用的最大化。     

Dynamic control of chiral space in a catalytic asymmetric reaction using a molecular motor

Enzymes and synthetic chiral catalysts have found widespread application to produce single enantiomers, but in situ switching of the chiral preference of a catalytic system is very difficult to achieve. Here, we report on a light-driven molecular motor with integrated catalytic functions in which the stepwise change in configuration during a 360° unidirectional rotary cycle governs the catalyst performance both with respect to activity and absolute stereocontrol in an asymmetric transformation. During one full rotary cycle, catalysts are formed that provide either racemic (R,S) or preferentially the R or the S enantiomer of the chiral product of a conjugate addition reaction. This catalytic system demonstrates how different molecular tasks can be performed in a sequential manner, with the sequence controlled by the directionality of a rotary cycle.     

Science and product

Much of what needs to be changed in U.S. industry involves close ties to manufacturing, design for manufacturability, a rapid design cycle, and up-to-date technical knowledge on the part of the engineers themselves. Being up-to-date requires conscious company effort. Traveling to meetings, reading the technical literature, and being a part of the engineering community are necessities if we are to compete with others who make these efforts and are thus better able to incorporate technical change rapidly into their own products. Outside the product improvement cycle, a research (as opposed to development) organization in industry must have close ties to development and manufacturing in order to succeed. With these close ties, researchers can understand the progress of the cycle and can introduce new steps at the appropriate time and in an acceptable form. A research organization that surmounts the internal barriers and becomes an accepted contributor to the development and manufacturing process can, because of its greater technical depth, its scientific knowledge, and its close ties with the university world, become a forceful initiator of progress. It is more difficult, in our opinion, to make these contributions from a university base and from government laboratories as they are now constituted. Much has been said by industry and government leaders about reforming the educational system and strengthening the national science base-things that help build a strong foundation. A strong science base supplies a vast storehouse of new ideas, and a good educational system provides engineers and manufacturing workers with knowledge; but strength here cannot make up for inadequacies in the functioning of the development and manufacturing cycle. The United States must learn to succeed, not only in the ladder type of innovation in which a wholly new idea from science creates a wholly new product (the science-dominated process at which we have succeeded in the past), but also in the rapid, cyclical, engineer-dominated process of incremental product improvement. Neither process is a substitute for the other; we need both.     

基于多层次模糊综合评价的中小企业信用风险评估

引入多层次模糊评价方法，设计包括行业状况、上下游状况、产品状况、管理水平、财务状况和资信状况的指标体系，构建多层次模糊综合评价的中小企业信用风险评估模型。算例分析表明该方法综合了定性因素和定量因素，能有效地评价中小企业的信用风险。     

The yeast cell cycle gene CDC34 encodes a ubiquitin-conjugating enzyme

Mutants in the gene CDC34 of the yeast Saccharomyces cerevisiae are defective in the transition from G1 to the S phase of the cell cycle. This gene was cloned and shown to encode a 295-residue protein that has substantial sequence similarity to the product of the yeast RAD6 gene. The RAD6 gene is required for a variety of cellular functions including DNA repair and was recently shown to encode a ubiquitin-conjugating enzyme. When produced in Escherichia coli, the CDC34 gene product catalyzed the covalent attachment of ubiquitin to histones H2A and H2B in vitro, demonstrating that the CDC34 protein is another distinct member of the family of ubiquitin-conjugating enzymes. The cell cycle function of CDC34 is thus likely to be mediated by the ubiquitin-conjugating activity of its product.     

Direct Observation of CIO from Chlorine Nitrate Photolysis

Chlorine nitrate photolysis has been investigated with the use of a molecular beam technique. Excitation at both 248 and 193 nanometers led to photodissociation by two pathways, CIONO(2) --> CIO + NO()2 and CIONO(2) --> Cl + NO3, with comparable yields. This experiment provides a direct measurement of the CIO product channel and consequently raises the possibility of an analogous channel in CIO dimer photolysis. Photodissociation of the CIO dimer is a critical step in the catalytic cycle that is presumed to dominate polar stratospheric ozone destruction. A substantial yield of CIO would reduce the efficiency of this cycle.     

缩短胶合板厚板热压周期的试验

对胶合板厚板作了缩短热压周期的试验，采用理论上较少采用的热压曲线与常规热压曲线进行对照，在２６２７张１５ｍｍ厚的胶合板试验中，由于采用新的热压曲线及缩短热压周期压制，试验结果表明，从板的物理力学性能及外观质量等均达到令人满意的结果．