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951.
D L Ranum 《Computer methods and programs in biomedicine》1989,30(2-3):209-215
A data acquisition tool which will extract pertinent diagnostic information from radiology reports has been designed and implemented. Pertinent diagnostic information is defined as that clinical data which is used by the HELP medical expert system. The program uses a memory-based semantic parsing technique to 'understand' the text. Moreover, the memory structures and lexicon necessary to perform this action are automatically generated from the diagnostic knowledge base by using a special purpose compiler. The result is a system where data extraction from free text is directed by an expert system whose goal is diagnosis. 相似文献
952.
953.
This report describes the results of a survey completed in December 1988 on the production and employment of PhDs and faculty in PhD-granting computer science/engineering departments during the 1987-8 academic year. All 127 computer science (CS) departments (115 US and 12 Canadian) participated. In addition, 34 departments offering the PhD in computer engineering (CE) were included. Throughout the report. CE statistics are reported separately so that comparisons with previous years can be made for CS. The intent is to merge all statistics for CS and CE after several years 相似文献
954.
C. N. Haas B. F. Severin D. Roy R. S. Engelbrecht A. Lalchandani S. Farooq 《Water research》1985,19(3):323-329
This paper summarizes studies on the presence of acid-fast and yeast organisms in wastewater and water treatment plants and in surface water. These organisms were found to satisfy three of Bonde's criteria for indicator organisms: presence whenever pathogens are likely to be present; resistance at least equal to that of pathogens; and lack of regrowth in the post-treatment environment. This, plus prior data, indicates that these organisms are at least as acceptable as indicators of disinfection efficiency than the coliform group. 相似文献
955.
The main purpose of this study was to evaluate the performance of the electrochemical oxidation process as a post-treatment for the effluents of a bench-scale UASB reactor treating simulated wastewater from an unbleached pulp plant. The oxidation process was performed using a single compartment cell with two plates as electrodes. The anode was made of Ti/Ru0.3Ti0.7O2 and the cathode of stainless steel. The following variables were evaluated: current density (75, 150 and 225 mA cm(-2)) and recirculation flow rate in the electrochemical cell (0.22, 0.45 and 0.90 L h(-1)). The increase in current density from 75 to 225 mA cm(-2) did not increased the color removal efficiency for the tested flow rates, 0.22, 0.45 and 0.90 L h(-1), however the energy consumption increased significantly. The results indicated the technical feasibility of the electrochemical treatment as post-treatment for UASB reactors treating wastewaters from pulp and paper plants. 相似文献
956.
Kahler Christopher W.; Read Jennifer P.; Wood Mark D.; Palfai Tibor P. 《Canadian Metallurgical Quarterly》2003,17(3):226
Structural equation modeling was used to test the mediational role of social environmental selection on alcohol use in cross-sectional samples of 447 students from a rural state university and 421 students from an urban private university. Results showed that male gender, White ethnicity, and sensation seeking were uniquely associated with greater alcohol use. Mediational analyses indicated that socioenvironmental factors (i.e., Greek involvement, friends' approval of drinking/getting drunk) were positively associated with alcohol use and significantly accounted for parts of the effects of ethnicity and sensation seeking, but not gender, on alcohol use. Results suggest that White students and those high on sensation seeking may drink more heavily in college, in part because they select social environments in which alcohol use is encouraged. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
957.
Features of complex waves excited in nonreciprocal guiding structures are considered in the case of a round shielded waveguide with a longitudinally magnetized axial ferrite core. 相似文献
958.
O. T. Tsyrul’nyk H. M. Nykyforchyn D. Yu. Petryna M. I. Hredil’ I. M. Dz’oba 《Materials Science》2007,43(5):708-717
We study the degradation of the mechanical and corrosion properties of 17G1S steel in gas mains as a result of operation for
28–40 yr. We reveal the simultaneous decrease in its strength and hardness, on the one hand, and impact toughness and crack
resistance, on the other hand. The indicated parameters prove to be most sensitive to the in-service degradation of the metal.
The degradation of steel leads to the increase in the strain-hardening coefficient and the appearance of the yield plateau
in the tensile stress-strain diagram and causes the appearance of sensitivity to hydrogen embrittlement increasing in the
process of operation. We analyze the role of absorbed hydrogen affecting the mechanism of strain aging and responsible for
the appearance of defects. It is shown that the polarization resistance can be used not only for monitoring of the corrosion
state of gas pipelines but also for the prediction of changes in their mechanical properties in the process of operation.
__________
Translated from Fizyko-Khimichna Mekhanika Materialiv, Vol. 43, No. 5, pp. 97–104, September–October, 2007. 相似文献
959.
A revision algorithm is a learning algorithm that identifies the target concept, starting from an initial concept. Such an algorithm is considered efficient if its complexity (in terms of the resource one is interested in) is polynomial in the syntactic distance between the initial and the target concept, but only polylogarithmic in the number of variables in the universe. We give an efficient revision algorithm in the model of learning with equivalence and membership queries for threshold functions, and some negative results showing, for instance, that threshold functions cannot be revised efficiently from either type of query alone. The algorithms work in a general revision model where both deletion and addition type revision operators are allowed. 相似文献
960.
Suppose that an equilibrium is asymptotically stable when external inputs vanish. Then, every bounded trajectory which corresponds to a control which approaches zero and which lies in the domain of attraction of the unforced system, must also converge to the equilibrium. This "well-known" but hard-to-cite fact is proved and slightly generalized here. 相似文献