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51.
Contends that there are 3 methodological errors and an inconsistency in M. E. P. Seligman's (see record 1996-13324-001) reanalysis of the 1995 Consumer Reports survey of the effectiveness of psychotherapy. These errors are directly relevant to the cost-effectiveness of psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
52.
An examination into the effects of carried military equipment on the performance of two tactical combat movement simulations was conducted. Nineteen Airfield Defence Guards performed a break contact (five 30-m sprints) and a fire and movement simulation (16 6-m bounds) in five load conditions (10–30 kg). Heavier loads significantly increased movement duration on the break contact (0.8%/kg load) and fire and movement (1.1%/kg). Performance deterioration was observed from the beginning to the end of the series of movements (bounds or sprints) with deterioration becoming significantly greater in heavier load conditions. Inter-individual variation between slower and faster participants showed a range in load effects; 0.6, 0.8%/kg for fast and 1.0, 1.4%/kg for slow (break contact, fire and movement, respectively). Velocity profiles revealed that the initial acceleration and peak velocity were the primary determinants of performance. As the duration of these tactical combat movements reflects periods of heightened vulnerability, these findings highlight important implications for commanders.
Practitioner Summary: Increasing amounts of carried military equipment impairs the performance of tactical combat movements. Examination of inter-individual variation in velocity profiles identified that the initial acceleration and the peak velocity achieved during sprints and bounds are key determinants of overall performance. 相似文献
53.
Analysis of the S-phase fractions (SPF) measured by in vitro thymidine labeling, morphological appearances, and estrogen receptor (ER) assays of primary invasive breast carcinomas demonstrated several interrelationships. Lobular, mucinous, tubular, and adenocystic carcinomas consistently had low SPF and were usually positive for ER. The same was true for the carcinomas of no special histologic type [the not otherwise specified (NOS) group of E. R. Fisher including "infiltrating ductal" and undifferentiated carcinomas] with minimal anaplasia. Medullary, atypical medullary, and morphologically unclassifiable carcinomas with marked nuclear anaplasia nearly always had high SPF and were usually negative for ER. High SPF was associated with advanced stages of carcinoma initially or with early recurrence following mastectomy. 相似文献
54.
Ohshiro, Hussain, and Weliky (2011) recently showed that ferrets reared with exposure to flickering spot stimuli, in the absence of oriented visual experience, develop oriented receptive fields. They interpreted this as refutation of efficient coding models, which require oriented input in order to develop oriented receptive fields. Here we show that these data are compatible with the efficient coding hypothesis if the influence of spontaneous retinal waves is considered. We demonstrate that independent component analysis learns predominantly oriented receptive fields when trained on a mixture of spot stimuli and spontaneous retinal waves. Further, we show that the efficient coding hypothesis provides a compelling explanation for the contrast between the lack of receptive field changes seen in animals reared with spot stimuli and the significant cortical reorganisation observed in stripe-reared animals. 相似文献
55.
J. F. Holzrichter D. Eimerl E. V. George J. B. Trenholme W. W. Simmons J. T. Hunt 《Journal of Fusion Energy》1982,2(1):5-45
Pulsed high power lasers can deliver sufficient energy on inertial fusion time scales (0.1–10 ns) to heat and compress DT fuel to fusion reaction conditions. Several laser systems have been examined for application to the fusion problem. Examples are Ndglass, CO2, KrF, and I2, etc. A great deal of developmental effort has been applied to the Ndglass laser and the CO2 gas laser systems. These systems now deliver >104 kJ and >20×1012 W to inertial fusion targets. The Nova Ndglass laser is being constructed to provide >200 kJ and >200×1012 W of 1 m radiation for fusion experimentation in the mid-1980s. For inertial fusion target gain, >100 times the laser input, it is expected that the laser must deliver 3–5 MJ of energy on the 10–20 ns time scale. This paper reviews the developments in laser technology and outlines approaches to construction of a 3–5 MJ driver. 相似文献
56.
L. R. Hunt 《Theory of Computing Systems》1979,13(1):361-376
LetM be a connected real-analytic 2-dimensional manifold. Consider the system
(t) = f(x(t)) + u(t)g(x(t)),x(0) =x
0 M, wheref andg are real-analytic vector fields onM which are linearly independent at some point ofM, andu is a real-valued control. Sufficient conditions on the vector fieldsf andg are given so that the system is controllable fromx
0. Suppose that every nontrivial integral curve ofg has a pointp wheref andg are linearly dependent,g(p) is nonzero, and that the Lie bracket [f,g] andg are linearly independent atp. Then the system is controllable (with the possible exception of a closed, nowhere dense set which is not reachable) from any pointx
0 such that the vector space dimension of the Lie algebraL
A
generated byf,g and successive Lie brackets is 2 atx
0.Research supported in part by the National Science Foundation under NSF Grant MCS76-05267-A01 and by the Joint Services Electronics Program under ONR Contract 76-C-1136. 相似文献
57.
This paper describes five successive interventions in the rearing of infants at an orphanage in Tehran, with their outcomes. The outcomes were assessed longitudinally. The first of the successive groups, here called "waves", numbered 15. These Ss constitute the controls. The only intervention consisted of examining the infants every other week during the first year and every fourth week thereafter with the ordinal, sensorimotor scales of Uzgiris and Hunt. The audio-visual intervention intended for the second wave of 10 infants was tape-recorded mother talk and music under the control of the infants and mobiles that the infants could activate. This plan was never adequately implemented because of inadequate supervision. The third wave of 10 infants got extra untutored human care. The fourth wave of 20 infants got the kind of audio-visual intervention originally intended for the second wave plus access to responsive inanimate materials. For the fifth wave, numbering 11, the infant-caretaker ratio was reduced to two or three to one and the caretakers were taught the Badger program supplemented with procedures to foster vocal imitation and semantic mastery of body parts, clothing, toys, and other objects and events regularly encountered. The results show that each successive wave, excepting the second, achieved the top steps of nearly all seven of the ordinal scales at mean ages younger than the preceding wave, and the fifth wave surpassed even home-reared American children from predominantly professional families in achieving the top steps on five of the seven scales. The findings show that infants need not advance along all branches simultaneously and that the kinds of experience encountered determine the branch along which advancement occurs. A number of theoretical implications are examined. Especially important is the idea that a dependable educational psychology for infancy and early childhood calls for much more knowledge than we now have of the kinds of experience that advance development along each of the various branches. 相似文献
58.
Xiaoyi Wang Scott Kangas Divyachapan Padur Lei Liu James A. Swanson Arthur J. Helmicki Victor J. Hunt 《Canadian Metallurgical Quarterly》2005,10(4):460-467
Condition assessment is a term that is used to describe the process of characterizing the physical condition of constructed systems. This paper summarizes a condition assessment (CA) procedure based on a complete system of field-testing, finite element (FE) modeling, and load rating. Experimental techniques, including both modal testing and truckload testing, are used to collect measurements of the constructed systems. The basic mechanism and procedure of the FE modeling and calibration are presented. Different physical parameters of FE models are adjusted during the calibration process using both static and dynamic responses as criteria to achieve convergence between experimental measurements and analytical results using carefully developed objective functions. Finally, a bridge load rating is completed on the basis of the calibrated model. These developments are described and illustrated using a representative bridge as an example. 相似文献
59.
Software development seems to be a discipline of artifacts; the developers spend their time producing products and attempting to find ways to measure just how well and how fast they make that product. We get pleasure from the act of creation and from activities that surround the creation process. But as time goes on, we start to lose sight of this. Companies are not interested in the process as much as the product. Managers cannot measure the thought that goes into a specification; they only see the document. 相似文献
60.
Finding changed identifiers is important for understanding the difference between two versions of a program and for detecting and resolving conflicts while merging variants of a program together. Standard practice for differencing and merging relies on line based techniques that do not recognize renamed identifiers. The design and implementation of a tool to automatically detect renamed identifiers between two versions of a program is presented. The system uses an abstract representation of language constructs to enable language awareness without introducing language dependence. Modules for Java and Scheme have been written. The detector works with multiple file pairs, taking into account renamings that span several files. A case study is presented that demonstrates proof of concept. The detector is part of a suite of intelligent differencing and merging programs that exploit the static semantics of programming languages. 相似文献