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排序方式: 共有191条查询结果,搜索用时 15 毫秒
121.
In this paper, the continuous-time linear Gaussian smoothing problem is investigated by utilizing a dual approach. It is shown that the smoothing problem is a dual of an optimal regulator with a jump condition on the trajectory. By solving the dual optimal control problem, basic results established earlier on this smoothing problem are derived in a simpler way. Results are also obtained for the discrete-time linear smoothing Gaussian problem. 相似文献
122.
The reconfigurable manufacturing system (RMS) is the next step in manufacturing, allowing the production of any quantity of highly customized and complex parts together with the benefits of mass production. In RMSs, parts are grouped into families, each of which requires a specific system configuration. Initially system is configured to produce the first family of parts. Once it is finished, the system will be reconfigured in order to produce the second family, and so forth. The effectiveness of a RMS depends on the formation of the optimum set of part families addressing various recon figurability issues. The aim of this work is to establish a methodology for grouping parts into families for effective working of RMS. The methodology carried out in two phases. In the first phase, the correlation matrix is used as similarity coefficient matrix. In the second phase, agglomerative hier archical Kmeans algorithm is used for the parts family for mation resulting in an optimum set of part families for reconfigurable manufacturing system. 相似文献
123.
Amita Gupta 《Journal of Early Childhood Teacher Education》2013,34(3):163-170
Abstract The author conducted a study with early childhood educators in New Delhi to understand the teachers’ perceptions of the relationship between their preparation and practice within a theory‐practice framework. The research problem emanated from the observations and experiences of the author, indicating an existing three‐way tension between the design of current Indian teacher education programs, the dominant discourse of early childhood education, and the underlying values of Indian philosophy that defined the construct of the teacher and child in Indian society. 相似文献
124.
Ram K. Gupta 《Journal of Experimental Education》2013,81(4):26-29
The purpose of this paper is to provide concrete illustrations of the efficacy of the multiple regression approach to the analysis of experimental results. A bridge between theoretical and specific applications is provided by parallel multiple regression and analysis of variance solutions for two typical educational designs. Detailed illustrations are given in the techniques of writing linear constraints and determining degrees of freedom. The major advantages of the multiple regression approach are its adaptability to unusual designs and the facilitation of meaningful interpretation afforded by the provision of regression weights in addition to the usual Fratios. 相似文献
125.
126.
AbstractThe aim of this study was to investigate the convergent and predictive validity of two skill tests that examine the ability of golfers to hit accurate approach-iron shots. Twenty-four high-level golfers (handicap = 2.6 ± 1.7) performed the Nine-Ball Skills Test (assesses the ability to shape/control ball trajectory with high accuracy) and the Approach-Iron Skill Test (assesses the ability to hit straight shots from varying distances with high accuracy). Participants then completed at least eight rounds of tournament golf over the following 90 days and reported an indicator of approach-iron accuracy (per cent error index). A moderate correlation (r = 0.50, P < 0.05) was noted between scores for both tests. Generalised estimating equations, using two covariates (lie of the ball and distance to hole), were used to determine model fit and the amount of variance explained for tournament per cent error index. Results showed that the Approach-Iron Skill Test was the slightly stronger predictor of on-course per cent error index. With both test scores considered together, a minimal amount of additional variance was explained. These findings suggest that either of the tests used individually or combined may be used to predict tournament approach iron performance in high-level golfers. 相似文献
127.
Dharamveer Yadav Sandhya Mishra Monika Gupta P. J. John Praveen Sharma 《Indian journal of clinical biochemistry : IJCB》2013,28(1):30-37
Reference intervals (RI) are the most common decision support tool used for interpretation of numerical laboratory reports. The quality of the RI can play as large a role in result interpretation as the quality of the result itself. As such there is hardly any study examining RI for liver specific biochemical parameters in Indian population especially north Indians having drastically different food habits as compared to rest of the India. So there is a need to establish the RI for north Indian population. Present study was conducted on 2,021 apparently healthy individuals of north Indian origin ranging in age from 15–60 years, were selected randomly using defined criteria. Lipemic, hemolysed, icteric and stored samples were also excluded adopting preanalytical criteria for rejection of sample. Non parametric methodology for determination of RI was adopted as most of the biochemical parameters included revealed non Gaussian distribution. Data were analyzed for middle 95 percentile (2.5th–97.5th percentile), median and 95 % confidence interval using SPSS software package version 10.0. The upper and the lower limit of RI (reported Vs observed) for bilirubin (0–1.2 Vs 0.30–1.30 mg/dL), serum glutamate oxaloacetate transferase (SGOT) (0–41 Vs 13–52.80 IU/L), serum glutamate pyruvate transferase (SGPT) (0–50 Vs 10–68 IU/L) showed wide variation as compared to reported standard RI however Gamma glutamyl transferase (GGT) (0–50 Vs 5.00–50.60 IU/L) remained within the reported standard RI. Further gender wise evaluation revealed higher cutoff in males (AST 14–55, ALT 11–70.35, GGT 6.76–51.09 in IU/L, bilirubin (0.40–1.34 mg/dL) as compared to females (SGOT 13–50.43, SGPT 9–63.43, GGT 3.92–48.70 in IU/L, Bilirubin 0.30–1.20 mg/dL) for both enzymatic and non enzymatic biochemical parameters. The variations may be attributed to dietary pattern smoking and alcoholism. 相似文献
128.
129.
Aniket Gupta Aadil Wani Anamika Joshi Haseeb Ahsan Rizwan Ahmad 《Indian journal of clinical biochemistry : IJCB》2014,29(1):63-68
Reactive oxygen species, as singlet oxygen (1O2), is continuously being generated by aerobic organisms, and react actively with biomolecules. At excessive amounts, 1O2 induces oxidative stress and shows carcinogenic and toxic effects due to oxidation of lipids, proteins and nucleic acids. In our study, immunoglobulin G (IgG) was modified by 1O2 generated by the ultraviolet (UV) irradiation of methylene blue. The modified IgG was characterized by UV spectroscopy, carbonyl content determination, thermal denaturation and electrophoretic study. Oxidation induced by modification of IgG by 1O2 also analyzed by scavenging studies. It was found that ultraviolet absorption spectra of modified IgG shows marked hyperchromicity. The carbonyl content was found to be high in modified IgG as compared to native IgG which confirms its oxidation. Thermal denaturation of modified protein sample shows decrease in Tm value by 3 °C and less intensity banding pattern on polyacrylamide gel electrophoresis. The quenching effect of sodium azide provides clue for modification of IgG by methylene blue, as it is known 1O2 scavenger. Hence, the IgG modified with 1O2 may be one of the etiological pathogenic factors for rheumatoid arthritis and diabetes. 相似文献
130.