为了解决应用于电动汽车与电网进行双向互动的双向DC/DC变换器的设计问题,对该变换器的应用环境特点、负载特性、双向有源桥和谐振式CLLC的特性等进行了研究。通过对实际应用场景和负载特点的分析,归纳出了应用在此类环境下的双向DC/DC...为了解决应用于电动汽车与电网进行双向互动的双向DC/DC变换器的设计问题,对该变换器的应用环境特点、负载特性、双向有源桥和谐振式CLLC的特性等进行了研究。通过对实际应用场景和负载特点的分析,归纳出了应用在此类环境下的双向DC/DC变换器应该选择能够在较宽增益变化范围内实现软开关的拓扑;通过结合实际应用场景,对比了双向有源桥和谐振式CLLC拓扑,选择了谐振式CLLC作为该变换器的基本拓扑;给出了基于谐振式CLLC拓扑的双向DC/DC变换器的设计流程及关键参数的计算公式;基于谐振式CLLC拓扑和流程设计了一台3 k W的双向DC/DC变换器。研究结果表明:以Si MOSFET为开关器件,当开关频率在100 k Hz以上时,变换器的正反向效率可以达到96.6%。展开更多
Objective： To observe the efficacy and safety of Jingui Shengqi Pill （金匮肾气丸, JSP） in treating partial androgen deficiency in aging males （PADAM）, and to explore the new approach in improving the quality of l...Objective： To observe the efficacy and safety of Jingui Shengqi Pill （金匮肾气丸, JSP） in treating partial androgen deficiency in aging males （PADAM）, and to explore the new approach in improving the quality of life in PADAM patients. Methods： Forty patients with PADAM were treated with JSP, the efficacy was evaluated with international index of erectile function （IIEF） scoring, PADAM questionnaire scoring, hormone, prostatic specific antigen （PSA）, etc., and the data before treatment were compared with those after treatment in the same group. Results： After 3 months of treatment, PADAM scoring and IIEF scoring were all significantly improved. Symptoms regarding physical ability, vasomotion, and psychical and mental condition all got improved more markedly than symptoms regarding sexual hypofunction. The serum level of testosterone was 3.85±0.36 before treatment and 5.02±0.83 after treatmnet （P〈0.05）; luteinizing hormone of 7.33±2.14 and 4.84±1.43 （P〈0.01）, follicule-stimulating hormone of 10.22±4.48 and 6.47±3.28 （P〈0.01）, respectively. The level of PSA failed to change significantly （1.94±0.55 and 2.06±0.47, P〉0.05）. Conclusion： JSP is effective and safe in treating PADAM, the mechanism of it is different from supplementing extrinsic androgen. It may have produced the effect by means of favorably regulating the condition of sex hormone to improve the balance of pituitary-sex gland axis, so it has more extensive clinical application.展开更多
The theory of nu-support vector regression (Nu-SVR) is employed in modeling time series variationfor prediction. In order to avoid prediction performance degradation caused by improper parameters, themethod of paralle...The theory of nu-support vector regression (Nu-SVR) is employed in modeling time series variationfor prediction. In order to avoid prediction performance degradation caused by improper parameters, themethod of parallel multidimensional step search (PMSS) is proposed for users to select best parameters intraining support vector machine to get a prediction model. A series of tests are performed to evaluate themodeling mechanism and prediction results indicate that Nu-SVR models can reflect the variation tendencyof time series with low prediction error on both familiar and unfamiliar data. Statistical analysis is alsoemployed to verify the optimization performance of PMSS algorithm and comparative results indicate thattraining error can take the minimum over the interval around planar data point corresponding to selectedparameters. Moreover, the introduction of parallelization can remarkably speed up the optimizing procedure.展开更多
文摘为了解决应用于电动汽车与电网进行双向互动的双向DC/DC变换器的设计问题,对该变换器的应用环境特点、负载特性、双向有源桥和谐振式CLLC的特性等进行了研究。通过对实际应用场景和负载特点的分析,归纳出了应用在此类环境下的双向DC/DC变换器应该选择能够在较宽增益变化范围内实现软开关的拓扑;通过结合实际应用场景,对比了双向有源桥和谐振式CLLC拓扑,选择了谐振式CLLC作为该变换器的基本拓扑;给出了基于谐振式CLLC拓扑的双向DC/DC变换器的设计流程及关键参数的计算公式;基于谐振式CLLC拓扑和流程设计了一台3 k W的双向DC/DC变换器。研究结果表明:以Si MOSFET为开关器件,当开关频率在100 k Hz以上时,变换器的正反向效率可以达到96.6%。
文摘Objective： To observe the efficacy and safety of Jingui Shengqi Pill （金匮肾气丸, JSP） in treating partial androgen deficiency in aging males （PADAM）, and to explore the new approach in improving the quality of life in PADAM patients. Methods： Forty patients with PADAM were treated with JSP, the efficacy was evaluated with international index of erectile function （IIEF） scoring, PADAM questionnaire scoring, hormone, prostatic specific antigen （PSA）, etc., and the data before treatment were compared with those after treatment in the same group. Results： After 3 months of treatment, PADAM scoring and IIEF scoring were all significantly improved. Symptoms regarding physical ability, vasomotion, and psychical and mental condition all got improved more markedly than symptoms regarding sexual hypofunction. The serum level of testosterone was 3.85±0.36 before treatment and 5.02±0.83 after treatmnet （P〈0.05）; luteinizing hormone of 7.33±2.14 and 4.84±1.43 （P〈0.01）, follicule-stimulating hormone of 10.22±4.48 and 6.47±3.28 （P〈0.01）, respectively. The level of PSA failed to change significantly （1.94±0.55 and 2.06±0.47, P〉0.05）. Conclusion： JSP is effective and safe in treating PADAM, the mechanism of it is different from supplementing extrinsic androgen. It may have produced the effect by means of favorably regulating the condition of sex hormone to improve the balance of pituitary-sex gland axis, so it has more extensive clinical application.
基金Supported by the National Natural Science Foundation of China (No. 60873235&60473099)the Science-Technology Development Key Project of Jilin Province of China (No. 20080318)the Program of New Century Excellent Talents in University of China (No. NCET-06-0300).
文摘The theory of nu-support vector regression (Nu-SVR) is employed in modeling time series variationfor prediction. In order to avoid prediction performance degradation caused by improper parameters, themethod of parallel multidimensional step search (PMSS) is proposed for users to select best parameters intraining support vector machine to get a prediction model. A series of tests are performed to evaluate themodeling mechanism and prediction results indicate that Nu-SVR models can reflect the variation tendencyof time series with low prediction error on both familiar and unfamiliar data. Statistical analysis is alsoemployed to verify the optimization performance of PMSS algorithm and comparative results indicate thattraining error can take the minimum over the interval around planar data point corresponding to selectedparameters. Moreover, the introduction of parallelization can remarkably speed up the optimizing procedure.
