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121.
This paper describes some of the spinoff benefits that can result from R&D projects, and categorizes them in terms of the dimensions of market and technical newness. These dimensions are discussed with reference to two types of spinoffs: 1) alternative market applications, when the results of an R&D project are subsequently applied to a market or use that differs from the originally intended application, and 2) second-generation technologies, when the technology that was the subject of an R&D project is significantly altered or enhanced in unanticipated ways through subsequent R&D. Examples from the Department of Energy's Energy-Related Inventions Program are integrated into the results of literature review to illustrate key concepts, including core technologies, degrees of market and technology newness, technology robustness, and the nature of connections linking spinoffs to prior R&D investments. The paper concludes by discussing spinoffs as a managerial strategy.  相似文献   
122.
The “tragedy of the commons” is the familiar problem that open access to a common property resource leads to overexploitation and to zero profits. A commons model is applied to an example of state sponsored private violence, the practice of privateering or licensed piracy. It is predicted that the presence of uncertainty about the value of the prey will reduce the amount of exploitation effort, and that industry profits may be positive due to both uncertainty and heterogeneous exploiters. Using data from England's wars with France and Spain between 1625 and 1630, the model suggests that the commons, represented by enemy merchant shipping, was not overexploited and that privateering profits were positive. The dynamic paths of privateering effort, ships seized, and individual firm profits were, however, consistent with the normal expectation that commons exploitation will peak and fall, as competition drives down returns through entry. “England was never richer than when at war with Spain.” Sir Edward Coke   相似文献   
123.
Vipond  Robert C. 《Publius》1993,23(3):39-56
On 26 October 1992, a majority of Canadians in a majority ofprovinces rejected the Charlottetown Accord in a national referendum.The accord capped the "Canada round" of constitutional negotiationsand attempted to satisfy Quebec, while also addressing otherpan-Canadian issues. The accord was defeated for different reasonsin different parts of the country. In Quebec, the "No" sideargued that the agreement did not meet their demands for greaterjurisdictionalautonomy within the federation. In the rest of Canada, the "No"side was particularly successful in demonstrating that the agreementdeviated from the principle of equality in the treatment ofindividuals and provinces. These critiques, inspired by differentvisions of the federation, lead in different directions. Inlight of these divisions, many commentators have suggested thatintergovernmental elites ought to abandon efforts of wholesaleconstitutional change. However, political developments in Quebecmay force these questions back onto the agenda.  相似文献   
124.
The author reviews current demographic trends in the countries of the European Community in the light of the efforts to abolish frontiers and border controls among member countries. She shows that there has been a general trend toward commonality in many aspects of demographic behavior.  相似文献   
125.
"Constitution of a trade bloc between Mexico, the United States and Canada through the North American Free Trade Agreement (NAFTA) in this decade has called attention to...the role of Mexico's southern border, Central American conflicts and migrations from that era. Relevant adjustments have been made to Mexico's policy in approaching problems regarding its southern neighbors. These changes respond largely to the perception held by larger economic blocs and migration generated by unequal development levels within these regions and countries." (SUMMARY IN ENG)  相似文献   
126.
127.
Surfmen are thus called young daredevils who climb to the roof of suburban trains in Rio de Janeiro, Brazil and vie with each other in agility and prowess, some of them often falling on the railway tracks and being killed. The practice started as a need to hang on anything outside the crowded train and became a sport of sorts. Even though repressed by the railway authorities and punished by fines and imprisonment, the practice has been going on since the eighties and developed into a competition with rules, code of honour, grading of achievement. It became a means of improving self-esteem as well as securing leadership and social prestige by people who otherwise carry on lives devoid of any charm or ludic stimulus. A substitute behavior, it results from processes of cultural elaboration at work in the youth culture of our cities.  相似文献   
128.
Measuring School-Related Stressors in Adolescents   总被引:2,自引:0,他引:2  
Some 1620 high school students responded to 68 items that measure adolescent stressors. Thirty-five of the items were based on J. P. Kohn and G. H. Frazer's Academic Stress Scale [1(1986) An Academic Stress Scale: Identification and Rated Importance of Academic Stressors, Psychological Reports, Vol. 59, pp. 415–426] developed in the United States, while the remaining 33 items were developed from P. Strutynski's [(1985) A Survey of Queensland Year 10, 11 and 12 Student Attitudes to Schools and Schooling, State Planning Committee, International Youth Year, Brisbane] lists of the most frequently named problems of 2336 Australian high school students. Confirmatory Factor Analysis was used to test and develop a measurement model developed from an extensive review of previous scales. The High School Stressors Scale emerged from the analytic process and measures nine school-related stressors. For researchers focusing on school-related problems and stressors among adolescents, the HSSS promises to be a very useful instrument. It has sound construct and predictive validity and adequate reliability, as demonstrated by the goodness-of-fit indices the squared multiple correlations.  相似文献   
129.
The purpose of this study was to examine in a sample of 11,516 secondary school students the extent to which different behavioral, emotional and cognitive problems (a) reflected one or more underlying common factors; (b) actually cooccurred; and (c) were single problems. Principal Component Analyses were performed and percentagewise techniques were used. PCA demonstrated that one or more general syndromes could not by far account for all of the variance of the variables. The results suggest the existence of adolescent subgroups with divergent comorbidity patterns: those who primarily report one single symptom; those who report concurrent symptoms either exclusively in the category of behavioral problems or exclusively in the category of emotional and cognitive problems; and those who report concurrent symptoms in both categories. This distinction between different subgroups has important theoretical, diagnostic, and treatment implications.  相似文献   
130.
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