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1.
What is the current standard of practice for evaluations of juvenile competence to stand trial (JCST)? The present study surveyed psychologists regarding the practices used when conducting JCST evaluations. Respondents rated the importance of 17 elements that might be included in a JCST evaluation report. Of these elements, 7 were considered essential by 70% or more of respondents, with 9 additional elements rated as either essential or recommended. A majority of respondents felt that the use of psychological and forensic instruments was important. A list of tests used is provided, and the implications for the development of standards and policy are discussed to provide practitioners with additional knowledge that will help to further the state of the discipline. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
One lesson learned from the Chernobyl accident was that the spatial distribution of far-field contamination was strongly non-uniform due to local variation of atmospheric conditions, such as wind direction, rain etc. An environmental monitoring system using highly sensitive thermoluminescent LiF:Mg,Cu,P (MCP-N) detectors has been completed and field-tested. The system consists of 3000 MCP-N detectors in 1000 TLD cards (three TLDs per card), two Mikrolab automatic TL readers, heating ovens, and specially developed software which includes a database for rapid evaluation of results. The main dosimetric parameters of MCP-N dosemeters, such as thermally-induced fading, light sensitivity, minimum detectable dose, self-dose, zero-dose, energy response up to 6-7 MeV, influence of annealing and readout conditions on detector stability, have been tested. About 100 locations over an area of about 15,000 km2 in the south of Poland were selected for measurements lasting from 4 days to 3 months. The kerma rates measured over a 4 day screening period agree well with kerma rates determined over a 75 day monitoring period. Results from short- and long-term exposure periods agree well with those performed using MTS-N (LiF:Mg,Ti) over southern Poland in 1985, before the Chernobyl accident. Thus, using the system based on MCP-N detectors, one is able simultaneously to monitor environmental radiation kerma rates at a large number of locations over periods of four days or less. Provided natural background kerma rates at selected monitoring points are available prior to the accident, the system can be applied to assess kerma rates rapidly in the environment, following a nuclear accident.  相似文献   
3.
Experiments were performed on 12 rabbits in 4 experimental groups: A. breathing spontaneously; B. nonparalysed and ventilated by means of a pump driven by the integrated phrenic nerve activity; C. paralysed and ventilated as mentioned above; D. like in the group C, but subjected to bilateral vagotomy. The relationships were investigated between the chosen basic parameters describing the rhythm and depth of respiration in steady states during exposure to hypercapnic mixtures. A high correlation was found between the amplitude of the integrated phrenic nerve activity and the time of inspiration which is modified by the afferent activities from the lungs and thorax TI and TE seem to be controlled by different mechanisms, and the contribution of TE to the control of the cycle duration is greater than that of TI.  相似文献   
4.
X-ray and optical measurements are used to show that the spontaneous strain (b/a-1) and optical birefringence Δnab in single crystals of ferroelectric PbBi2Nb2O9 are a function of the state of electrical poling, going to a zero in the unpoled state. In poled crystals all spontaneous strain is lost at a temperature ≃200°C below the dielectric Curie temperature in a manner reminiscent of the behavior of the perovskite relaxor ferroelectrics which have diffuse phase transitions.  相似文献   
5.
A novel ZnO-based composite material is fabricated by oxidation of Zn alloy melts, in which outward growth of the reaction products and rapid reaction kinetics are observed. Additions of Na and Bi to the Zn melts are found to be essential to increase the matrix growth rate to a practical level. Optimum reaction rates are observed for Zn-3Na-5Bi alloys oxidized at temperatures between 450 and 550°C in pure oxygen. Processing parameters, such as alloy composition and oxygen activity, also have a profound impact on the resulting microstructure and reaction kinetics. The evidences supported that the continuous outward growth of the matrix is achieved via modification of the ZnO defect structure and partial wetting of the growing oxide by the melts.  相似文献   
6.
Sorption cryocoolers utilize metal hydride sorbent beds for the closed-cycle circulation of gaseous hydrogen through heat exchangers and a Joule-Thomson (J-T) expansion valve in order to achieve cold-stage temperatures below 30 K. These devices have high potential for satellite missions that require long term reliability, minimal vibrations, and low operating power. Designs for nominal 25 K liquid and 10 K solid hydrogen refrigerators are described. Prototype hydride sorbent beds for breadboard studies of sorption cryocoolers have been fabricated and tested to simulate expected operation. The sorbents contained in the beds are VHx, LaNi5−ySnyHx, and ZrNiHx. Some of these hydride beds have been integrated with a hydrogen J-T cold-stage. These experiments confirm that the selected metal hydrides and bed designs satisfy the constraints associated with the proposed liquid and solid hydrogen cryocoolers.  相似文献   
7.
This paper describes a method for texture based segmentation. Texture features are extracted by applying a bank of Gabor filters using two-sided convolution strategy. Probability texture model is represented by Gaussian mixture that is trained with the Expectation-maximization algorithm. Texture similarity, obtained this way, is used like the input of a Graph cut method. We show that the combination of texture analysis and the Graph cut method produce good results.  相似文献   
8.
There is, as yet, no universally agreed upon method for the detection of spontaneous otoacoustic emissions (SOAEs). In this paper, we augment extant techniques by presenting a new automated approach. The new procedure reliably labels the spectral peaks as SOAEs, rejects noisy data such as that due to body movements or breathing, provides a subject-specific measure of the probability that a particular peak is erroneously identified as a SOAE, and can be accomplished on-line. Comparison of results with this new approach and with methods undertaken previously in this laboratory and elsewhere are made. The estimated prevalence of SOAEs for the new method is as large as that for any method previously proposed.  相似文献   
9.
Zusammenfassung   In der Industrie besteht derzeit ein wachsender Bedarf an Informatikern, die über Kenntnisse und Erfahrungen mit objektorientierten Techniken verfügen. Um diesem Bedarf Rechnung zu tragen, ist eine st?rkere Einbeziehung dieser Thematik in die Informatik-Lehrpl?ne unverzichtbar. Aus didaktischer Sicht kommt in diesem Zusammenhang der Wahl einer geeigneten Ausbildungssprache eine besondere Bedeutung zu. Gerade unter diesem Aspekt zeigt sich die überlegenheit der rein objektorientierten Programmiersprache Eiffel. Eingegangen am 03.11.1997  相似文献   
10.
J. P. Das et al (see record 1975-08765-001) claim that A. R. Luria's (1966) distinction between simultaneous and successive modes of information processing provides a more fruitful way of classifying cognitive processes than (a) the hierarchical models of C. Burt (see record 1973-10531-001) and P. E. Vernon (see record 1963-03855-001), A. R. Jensen's (see record 1969-09740-001) Levels 1 and 2, or A. Paivio's (see record 1976-01839-001) dual coding system of imagery and verbal mediation. Their published factor analyses are surveyed, and shown to yield only partial support for their views. A broader battery of 14 tests was given to 91 university students, and responses were factor analyzed. Two of the obtained factors involved various kinds of rote memorizing, and thus could be regarded as successive processing. Four other factors did not yield a general simultaneous factor, but classified the tests under Number-Spatial, Verbal-Spatial, Perceptual Reasoning, and a specific Digit Memory factor. Overall, the 6 factors tend to follow a multiple-factor, or a hierarchical model, rather than a dichotomous classification. (French summary) (28 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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