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81.
In this paper a method for the realization of RC transfer immittance functions with an unsymmetrical lattice is presented. The method yields minimal capacitor realizations for Z12(s) with no pole at s = 0 and ?y12(s) having no pole at s = ∞. The number of resistors needed are only two more than the minimum needed.  相似文献   
82.
The difficulties in solving Fredholm integral equations of the first kind are well known. A classical method has been to convert the equation into a set of m linear algebraic equations in n unknowns (m?n). For computational convenience, it is customary to force m = n and solve the resulting ill-conditioned system using one technique or other. In the general case, a feasible solution, if it exists, can be found by determining the generalized inverse of the coefficient matrix. One method of finding the generalized inverse is to reformulate the problem and observe the steady state response of a system of ordinary differential equations with prescribed initial conditions. Results obtained from this reformulation are found to be comparable in quality to those obtained earlier by other methods. Analog and digital computer implementations are discussed.  相似文献   
83.
84.
The present study comprised 100 patients of essential hypertension who were screened for fasting hyperinsulinemia, which was detected in 77% cases. Twenty such hyperinsulinemic cases were subjected to 4 weeks of dietary control phase followed by 6 weeks of omega-3 fatty acids substitution [either 0.6 g/d (group 1) or 1.2 g/d (group 2)]. The mean basal fasting plasma insulin levels were significantly higher (p<0.001) in patients of hypertension when compared to normal controls (126.51±80.36 and 19.35±12.61 μU/ml respectively). At the end of 4 weeks of diet control only, no significant change was observed in any parameter. After substitution of omega-3 fatty acid, a significant reduction of fasting plasma insulin levels in both group 1 (29%) and group 2 (22.8%) was observed (p<0.001). Significant reduction of systolic and diastolic blood pressure (16.4% and 25% respectively), serum cholesterol, triglycerides and low density lipoprotein was also noted in both groups (p<0.001), while high density lipoprotein increased by ∼8 mg% in both groups. Thus omega-3 fatty acid substituion in low dose along-with curtailment of dietary omega-6 fatty acid may be used as an adjunctive measure in the management of essential hypertension.  相似文献   
85.
Polarography     
J Heyrovsky’s invention of polarography in which a dropping mercury electrode is used in the electrochemical cell revolutionised electroanalysis, study of electrode kinetics and adsorption studies on mercury electrodes. Polarography has also directly contributed to the development of new and innovative ideas in electrochemical techniques, instrumentation and applications  相似文献   
86.
This paper considers the history of the emergence and development of cooperative cataloging in Russia and abroad and presents the first projects and programs in the field of cooperative cataloging: CONSER, NACO, BIBCO, and PCC. It elucidates the activity of the OCLC Center and Consortium of European Scientific Libraries, which are the first-rate international cooperative associations, as well as the ARBIKON Association and LIBNET centers which are Russian centers of cooperative cataloging.  相似文献   
87.
This paper analyzes modern information technologies as applied in the political environment and considers the content and peculiarities of using IT programs in strategic political modeling.  相似文献   
88.
The main aspects of the creation of a monitoring system for the research activities of the members of a higher-education institution are considered. The scientific activities of the lecturers and members of Turgenev Orel State University is used as the basis. It is expected that this system will be an efficient tool for optimal managerial decisions at all levels.  相似文献   
89.
Given that physical activity (PA) tends to decrease with age during adolescence, addressing factors that affect change is important. This study examined the similarity and interdependence of PA as influenced by psychosocial factors among adolescent best friend dyads. A total of 660 adolescents, representing 330 best friend dyads, completed questionnaires with regard to PA, sitting time, perceived exercise benefits and barriers, physical self-perception and social support for PA. Dyads were also identified as reciprocal and non-reciprocal best friends; reciprocal means that both considered each other best friends and non-reciprocal were those in which only one considered the other a best friend. Data were analysed using a hierarchical linear model framework. Results indicated significant similarities between reciprocal best friend dyads for PA and sitting time, and for sitting time in non-reciprocal best friends (P values <.01). Psychosocial variables were associated with PA in reciprocal best friend dyads and with sitting time in reciprocal and non-reciprocal best friend dyads. Best friend gender, regular sports practice of the person, perceived exercise barriers of the best friend and best friend social support were the best predictors for PA.  相似文献   
90.
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