百万等级机组塔式锅炉螺旋水冷壁安装工艺研究

上海外高桥第三发电厂2×1000MW机组工程拥有二台超超临界的塔式锅炉,针对其螺旋水冷壁的安装特点,设计制造了一副炉膛内垂直升降吊架满足安装需要。本文总结和论述该吊架在1000MW机组锅炉安装中的设计与应用。     

Progression,Stability, or Decline? Sociological Mechanisms Underlying Change in Specialization Among Birdwatchers

Using a panel of American birdwatchers collected in 1997 and 2002, we tested the extent to which birdwatchers progressed over a five-year period. The impact different career contingencies and life course events had on predicting change in birdwatchers' behavior, skill, and commitment was also examined. Findings indicated that although progression characterized some birdwatchers' participation, involvement by others was better characterized by stability or decline, which was true for each of the indicators used to measure specialization. Career contingencies and life course changes had only a moderate influence on predicting change in the specialization indicators over time. Support from family members and retirement were the best predictors of change in specialization.     

民营企业的经营抉择:专业化或多元化

民营企业是专业化发展还是多元化经营,一直困扰着民营企业家。文章认为,目前中国的民营企业正在分化为两大趋势:一部分企业坚守岗位,深化自己产业的深度、纵度、精细化;另一部分企业则开始朝着多元化趋势发展。应根据企业规模、企业在本产业的发展潜力等具体情况,决定发展模式。     

在远程教育下提升教师专业化知识中的价值研究

教师专业化成为教师自身发展的必然要求,已成为世界各国教育者研究的趋势和潮流。通过研究教师专业化的开放性、阶段性、动态性、实践性等特征,分析了远程教育教师应具备素养性知识、条件性知识、行为性知识、实践性知识等知识类别。     

Product Differentiation in the Spanish Beef Industry

Abstract

This paper aims to investigate changes in the structure of the Spanish quality beef industry in response to the significant decline in beef consumption happened over the last few decades. The role of product differentiation, mechanisms and factors involved in it, are specially studied. We use focus groups and a survey to examine the outlook for the organization of the beef industry, and trends in the development of product differentiation mechanisms and vertical co-ordination strategies.

Results reveal the existence of a restructuring process that is being implemented in two ways: Protected Geographical Indications (PGI) and Quality Certified Brands (QCB). Each strategy forms its own entry barriers: the origin of calves in the case of PGI and farm size in QCB; they are therefore complementary rather than competitive.     

铰链门垂直刚度探析

铰链门的设计要素及评价指标较多,其中最重要的要素是垂直刚度指标。垂直刚度指标的确立及研究对车门设计具有指导意义。文章重点阐述了垂直刚度的分析方法及指标。     

立板补焊试件的焊接工艺

根据第三届全国职工职业技能大赛立板补焊项目的培训经验,介绍此项目的操作方法及具体工艺措施。焊后经检测,焊缝外观成形及无损探伤均满足相关标准要求。     

川西浅层水平井轨迹控制技术

浅层水平井井眼轨迹控制技术是浅层水平井施工的关键环节之一,针对浅层水平井的钻井特点和影响井眼轨迹控制的因素,对现有钻具组合造斜率预测方法进行分析;针对浅层水平井井眼轨迹控制工艺和工具设计提出了一些技术措施,并结合川西浅层水平井钻井情况,总结了浅层水平井井眼轨迹控制工艺技术,得出了浅层水平井井眼轨迹控制几点建议,为今后在川西浅层施工的长水平段水平井积累实钻经验。     

Announcements

Abstract

In this study we examined the effect of specialization on behavioral choice among Wisconsin goose hunters, who were able to choose a relatively easy hunt at the Horicon Marsh or a more complex hunt in the exterior zones. Past research has shown that more specialized recreationists have differing motives, attitudes, satisfaction levels, crowding perceptions, environmental preferences, and management preferences. Our goal in this study was to extend this research to behavioral choices and to learn more about the dimensions of specialization in goose hunting. Specialization did not predict behavioral choice among the sample. Specialization, as measured by past experience, commitment, media involvement, club membership, and preferred hunting style, did not differ significantly when comparing Horicon goose hunters and exterior zone hunters. Novice hunters hunted alongside experienced hunters, and behavioral choice appeared to be more a function of structural constraint than attitu‐dinal preference. Specialization did explain differences in hunter judgments of quality, correlating negatively with shooting and bagging and positively with social and natural components of a quality experience. These findings indicate that although the specialization framework can effectively predict attitudinal differences among participants in a given activity, it is less efficient at predicting behavioral choice. Consequently, specialization researchers need to be cautious about inferring levels of specialization from observations of locational choice.     

Minutes of Spring Council Meeting, 1966, of the Catholic Economic Association

Alongside neo-classical supply-side analysis, there was the emergence in the 1980s of a new strand of anlysis seeking to develop a social-institutional perspective on the supply-side of modern industrial economies. This paper contrasts the views of labor market ‘flexibility’ provided by neo-classical analysts and supporters of deregulation with those of the Flexible Specialization and Diversified Quality Production theorists and assesses the strengths and weaknesses of Flexible Specialization in comparison to its main ‘institutionalist’ rival. It concludes that the anlysis of ‘supply-side institutionalism’ and the evidence provided by important empirically based studies, suggests that public policy directed towards: optimizing job training, promoting employee participation and inter-firm co-operation, and restricting the ability of firms to indulge in short-termism will be most productive in promoting the cause of socially progressive industrial production and ‘goodwork’.