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Dilemmas in a general theory of planning 总被引:49,自引:0,他引:49
The search for scientific bases for confronting problems of social policy is bound to fail, becuase of the nature of these problems. They are wicked problems, whereas science has developed to deal with tame problems. Policy problems cannot be definitively described. Moreover, in a pluralistic society there is nothing like the undisputable public good; there is no objective definition of equity; policies that respond to social problems cannot be meaningfully correct or false; and it makes no sense to talk about optimal solutions to social problems unless severe qualifications are imposed first. Even worse, there are no solutions in the sense of definitive and objective answers.This is a modification of a paper presented to the Panel on Policy Sciences, American Association for the Advancement of Science, Boston, December 1969. 相似文献
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The Dayton/Montgomery County Criminal Justice Center is a first attempt at systematic personnel development for an entire criminal justice system on a regional level. Through its work in training and education, communications, career pathing and development, and system change, the Center has promoted the idea of an improved, symbiotic relatioship among the major branches of the criminal justice system, and has acted as a catalyst for needed systemic change. 相似文献
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Cardiac injuries incurred by drivers in automobile accidents 总被引:1,自引:0,他引:1
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Thevissen PW Poelman G De Cooman M Puers R Willems G 《Forensic science international》2006,159(Z1):S40-S46
Modifying and implanting existing RFID-tags into extracted human molars was described previously [P. Thevissen, G. Poelman, B. Puers, M. De Cooman, G. Willems, Implantation of RFID-tag into human molars to reduce hard forensic identification labor. Part 1. Working principle, Forensic Sci. Int. 156 (2006)]. Maximal vertical occlusal load during which the implanted RFID-tags remain active was evaluated in vitro. The temperature dependency of the implanted RFID-tags was studied on the extracted teeth to find out the maximal obtainable temperature before failure and a test with embedded thermistors to verify temperature distributions. The maximal working temperature of the implanted RFID-tags was revealed and gave indications for the set-up of measuring intra oral and intra tooth temperature during the cremation of a human body. Fatigue was induced on the implanted teeth by thermocycling. The results of this investigation showed the need of putting an extra insulating layer around the modified tags before implantation. The different in vitro tests indicated that the implanted RFID-tags can support certain oral and forensic circumstances. 相似文献