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891.
Patenaude Andrea Farkas; Guttmacher Alan E.; Collins Francis S. 《Canadian Metallurgical Quarterly》2003,58(4):319b
Responds to the comments of H. Goldsmith et al (see record 2003-05602-013) and S. Kéri (see record 2003-05602-014) regarding the article by A. Patenaude et al (see record 2002-12457-022) that discusses the role of psychologists in genetics and genetic testing. Patenaude reviews the comments made and states that both comments enlarge the discussion of the important roles psychologists will continue to play as genetics advances the knowledge of the etiology and treatment of disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
892.
Although the origins of clinical psychology may be traced to the efforts of L. Witmer in the last century, contemporary clinical psychology, involving therapy as well as diagnostics, evolved in the years immediately following World War II. The 1st specialty programs leading to the PhD in clinical psychology were instrumental in shaping that evolution. This article describes the state of training before the specialty programs and how the specialty programs were developed. Their significance to licensing, accreditation standards, and other professional issues is explored. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
893.
Maurer U. Wolf S. 《IEEE transactions on information theory / Professional Technical Group on Information Theory》2003,49(4):832-838
For pt.I see ibid., vol.49, no.4, p.822-31(2003). In the first part, we showed that when two parties, willing to generate a secret key, but connected only by a completely insecure communication channel, have access to independent repetitions of some random experiment, then the possibility of secret-key agreement depends on a certain property, called simulatability, of the probability distribution modeling the parties' initial knowledge. More generally, the simulatability condition is important in the context of identification and authentication among parties sharing some correlated but not necessarily identical partially secret keys. Unfortunately, this condition is a priori not very useful since it is not clear how to decide efficiently whether it is satisfied or not for a given distribution P/sub XYZ/. We introduce a new formalism, based on a mechanical model for representing the involved quantities, that allows for dealing with discrete joint distributions of random variables and their manipulations by noisy channels. We show that this representation leads to a simple and efficient characterization of the possibility of secret-key agreement secure against active adversaries. 相似文献
894.
M. Batz S. Bae?ler W. Heil E. W. Otten D. Rudersdorf J. Schmiedeskamp Y. Sobolev M. Wolf 《Journal of research of the National Institute of Standards and Technology》2005,110(3):293-298
The strongly spin-dependent absorption of neutrons in nuclear spin-polarized 3He opens up the possibility of polarizing neutrons from reactors and spallation sources over the full kinematical range of cold, thermal and hot neutrons. This paper gives a report on the neutron spin filter (NSF) development program at Mainz. The polarization technique is based on direct optical pumping of metastable 3He atoms combined with a polarization preserving mechanical compression of the gas up to a pressure of several bar, necessary to run a NSF. The concept of a remote type of operation using detachable NSF cells is presented which requires long nuclear spin relaxation times of order 100 hours. A short survey of their use under experimental conditions, e.g. large solid-angle polarization analysis, is given. In neutron particle physics NSFs are used in precision measurements to test fundamental symmetry concepts. 相似文献
895.
Alan L. Migdall Carsten Winnewisser 《Journal of research of the National Institute of Standards and Technology》1991,96(2):143-146
The effect of optical irradiance on the linearity of a Si photodiode was studied. These results are compared for light modulated at 30 MHz and at dc as the optical irradiance was varied over a 9 decade range. We discuss how these results affect the use of this detector as a heterodyne receiver. As the optical irradiance varied from 10−2 to 10+3 mW/cm2, while maintaining constant total power, the photocurrent was constant to about 1%, but as the power density increased further, the photocurrent increased about 13%. At the highest densities that we could achieve, about 6×107 mW/cm2 there was only slight evidence of the onset of saturation. These results are of importance in our work to use optical heterodyne detection to measure filter transmittances over a wide dynamic range. The results provide guidelines for achieving maximum accuracy when using this particular diode as an optical heterodyne receiver. 相似文献
896.
897.
David R. McLean Brenda J. Page Alan Tuchman Andrew V. Kispert Wen L. Yen
William J. Potter
《Expert systems with applications》1992,5(3-4):441-446Classical planning systems attempt to solve a planning problem by avoiding possible conflicts before the actions are put on a timeline. This is computationally very expensive and the search for all possible future conflicts may be prohibitive. A conflict resolution approach can check for immediate conflicts and try conflict resolution strategies as each activity is put on a timeline without regard for possible future conflicts. A more practical approach is to use a combination of conflict avoidance and conflict resolution based upon heuristics which limit the amount of search required when either is used. Because humans are not good at solving problems which require complex lookahead, this combined approach, with emphasis on conflict resolution, is what human schedulers actually use when they develop schedules. A system which simulates this human approach to scheduling has been developed at NASA's Goddard Space Flight Center for scheduling satellite activities. This system, which includes the Planning And Resource Reasoning (PARR) shell, allows expert schedulers to specify conflict resolution strategies as well as conflict avoidance strategies to be used during the scheduling process. PARR has been used since May 1987 to schedule the Tracking and Data Relay Satellite System services for the Earth Radiation Budget Satellite. PARR will also be used to schedule platform resources on the Explorer Platform, scheduled for launch in early 1992. This paper describes the advantages of using a combined conflict avoidance and resolution approach in a satellite scheduling system. 相似文献
898.
NEW YORK—Wal—Mart继续稳坐其美国最大公司的宝座,再一次在《财富》杂志的年度财富500强评选中拔得头筹。
在其5月5日一期的杂志中,该刊物称,首席执行官Lee Scott去年秋季做出的将畅销消费电子产品、玩具及其他产品的节日促销价格大幅削减20%的决定为公司带来了1000亿美元的销售奇迹, 相似文献
899.
S. Moehmel N. Steinfeldt S. Engelschalt M. Holena S. Kolf M. Baerns U. Dingerdissen D. Wolf R. Weber M. Bewersdorf 《Applied Catalysis A: General》2008,334(1-2):73-83
For converting methane and ammonia to hydrocyanic acid, catalysts were prepared and tested in a 48-parallel channel fixed-bed reactor unit operating at temperatures up to 1373 K. The catalysts were synthesized with a robot applying a genetic algorithm as the design tool. New and improved catalyst compositions were discovered by using a total of seven generations each consisting of 92 potential catalysts. Thereby, the catalyst support turned out as an important input variable. Furthermore, platinum, which is well known as a catalytic material was confirmed. Moreover, improvements in HCN yield were achieved by addition of promoters like Ir, Au, Ni, Mo, Zn and Re. Multi-way analysis of variance and regression trees were applied to establish correlations between HCN yield and catalyst composition (support and metal additives). The obtained results are considered as the base for future even more efficient screening experiments. 相似文献
900.
By Steve Smith 《消费电子商讯》2008,(11):24
乔治·格拉诺夫,Tweeter的总裁兼首席执行官(左),出席了他的第一场PRO(渐进零售商组织)小组的春季会议,向供应商介绍一个新的商业模式,此 相似文献