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41.
42.
I read with chagrin Donald T. Campbell's (see record 1990-55812-001) comments on my article on the preparation of researchers in psychology. In "Thesis-Antithesis" (American Psychologist, 1966, 21, 781-787; see record 1967-00924-001), I examined some hidden assumptions upon which the thesis requirement rests and attempted to bring into relationship recent ideas in epistemology with earlier recommendations of the Education and Training Board. I suggested that if the future face of psychological investigations is to be more like search and less like research, we shall have to recapture and invest with meaning the personal qualities in the advisory relationship, often lost sight of under the pressure of academic requirements. I claimed that some degree requirements discourage the personal and professional evolution of the future generation of researchers. Campbell's criticism that I recommended the substitution of research assistantships for the thesis requirement leaves me feeling like the guest in a famous restaurant. The waiter wished to know how the guest would like his tournedos bordelaise. "A center cut and tenderloin portion, by all means, quite well done on the outside, then slightly pink, and, finally, seigneuse in the middle, not a very large portion, just right, with some gently braised mushrooms on the side, and only a touch of sauce," said the guest. The waiter nodded with approval, then turned into the kitchen with the usual refrain: "T-bone coming up." What can one do? (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
43.
This is an extension of the Bridged-T infinite rejection network idea transformed into microwave concepts. These devices achieve approximately 100db of attenuation with skirt attenuations approximately 5db. The tuning range between 1 KMc and 10 KMc is continuously covered with 4 units at present. Work is continuing to reduce the number of units to 2. Design parameters, performance curves, and application to MILSTD 826 will be discussed.  相似文献   
44.
In exp. I with 3 male and 1 female o, the bisensory recognition of simultaneously presented auditory and visual verbal information was measured as a function of auditory and visual recognition. It is shown that bisensory performance is superior to performance predicted by a model that assumes the 2 modalities are processing the information independently. Instead integrative processing is suggested. In previous studies using theory of signal detectability (tsd), independent processing of bisensory presentations of mathematically equivalent stimuli has been shown. Present results suggest that the mathematically equated stimuli in those studies were not cognitively equivalent. Exp. Ii with 3 male os lends support to this notion by (a) using verbal information in a tsd paradigm, and (b) showing that when the stimuli are equivalent the results are consistent with a model in which bisensory processing occurs integratively on a common decision axis. However, when the stimuli to each mode are not equivalent, results are consistent with a model in which bisensory processing occurs independently on separate decision axes. (french summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
45.
A histopathologic study of macular cysts and holes   总被引:1,自引:0,他引:1  
Forty-four eyes from 39 patients with either lamellar macular holes (17 eyes), full-thickness macular holes (18 eyes), and/or macular cysts (9 eyes) were studied histopathologically. Lamellar and full-thickness holes were frequently found in eyes with a history of trauma or ocular surgery. Diabetes mellitus was the most common condition associated with macular cysts. Four lamellar holes and four full-thickness holes occurred in eyes with senile macular degeneration. Six lamellar holes, eight full-thickness holes, and one macular cyst developed on an idiopathic basis. Residual cystoid macular edema was the most prevalent accompanying pathologic feature. Cystoid macular edema was also noted in the opposite eye in seven cases of lamellar and full-thickness holes. A preretinal glial membrane, thought to be a secondary change, was found at or near the edges of the lamellar or full-thickness holes or over the macular cyst in the majority of cases. Wrinkling of the internal limiting membrane (ILM) was present in five cases. Vitreous traction, with or without an operculum, was infrequently associated with these entities.  相似文献   
46.
Sheep perinephric fat has been found to contain 11-cyclohexylundecanoic acid to the extent of approximately 0.05% of the total weight of fatty acids.  相似文献   
47.
The Ni22Cr10Al1Y alloy was exposed in H2/H2S gas mixture under the sulphur pressure 10–3 and 1 Pa as well as in SO2 at 1173 and 1273 K. At ps = 1 Pa the sulphidation rate was relatively high and the reaction obeyed the linear rate law. Under these conditions a nickel/nickel sulphide eutectic was formed. At ps = 10–3 Pa nickel sulphides became unstable and the sulphidation rate was significantly lower. The reaction obeyed the parabolic rate law. The oxidation rate of the alloy in SO2 was lower than that in any of the H2/H2S atmospheres. The sulphide scales formed during sulphidation in H2/H2S had complex microstructures and compositions, with sulphospinel and sulphide phases being present, e.g. NiCr2S4, Ni3S2, CrxSy. As the temperature increased and the sulphur pressure decreased, these phases were replaced by the chromium-rich sulphide phase. Various oxides formed during oxidation of the alloy in SO2.  相似文献   
48.
This paper analyses how context- and time-dependent factors determine the impact of R&D subsidies on firm behaviour with respect to private R&D expenditures. Based on German R&D survey data, we combine propensity score matching with a difference-in-difference estimator in order to measure the causal influence of public direct R&D project funding on firm behaviour. Our results indicate that (i) repeated participation in R&D projects on average leads to a higher increase in R&D expenditures than once-off funding; (ii) the aggregate effect of R&D funding on R&D expenditures of business firms is somewhat higher for business–business collaboration projects than for science–business collaboration projects; (iii) R&D expenditures of business firms that cooperate with science show a higher share of external R&D spending. Results of one particular cluster programme indicate that at least the short-term development of R&D does not so much depend on which programme direct R&D project funding is applied to.  相似文献   
49.
Multiple Sequence Alignment (MSA) is an important problem in Bioinformatics that aims to align more than two sequences in order to emphasize similarity regions. This problem is known to be NP-Hard, so heuristic methods are used to solve it. DIALIGN-TX is an iterative heuristic method for MSA that generates alignments by concatenating ungapped regions with high similarity. Usually, the first phase of MSA algorithms is parallelized by distributing several independent tasks among the nodes. Even though heterogeneous multicore clusters are becoming very common nowadays, very few task allocation policies were proposed for this type of architecture. This paper proposes an MPI/OpenMP master/slave parallel strategy to run DIALIGN-TX in heterogeneous multicore clusters, with several allocation policies. We show that an appropriate choice of the master node has great impact on the overall system performance. Also, the results obtained in a heterogeneous multicore cluster composed of 4 nodes (30 cores), with real sequence sets show that the execution time can be drastically reduced when the appropriate allocation policy is used.  相似文献   
50.
ABSTRACT

Advanced high strength steels are usually coated by a zinc layer for an increased resistance against corrosion. During the resistance spot welding of zinc coated steel grades, liquid metal embrittlement (LME) may occur. As a result, cracking inside and around the spot weld indentation is observable. The extent of LME cracks is influenced by a variety of different factors. In this study, the impact of the used electrode geometry is investigated over a stepwise varied weld time. A spot welding finite element simulation is used to analyse and explain the observed effects. Results show significant differences especially for highly increased weld times. Based on identical overall dimensions, electrode geometries with a larger working plane allow for longer weld times, while still preventing LME within the investigated material and maintaining accessibility.  相似文献   
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