Parameters identification for photovoltaic module based on an improved artificial fish swarm algorithm.

A precise mathematical model plays a pivotal role in the simulation, evaluation, and optimization of photovoltaic (PV) power systems. Different from the traditional linear model, the model of PV module has the features of nonlinearity and multiparameters. Since conventional methods are incapable of identifying the parameters of PV module, an excellent optimization algorithm is required. Artificial fish swarm algorithm (AFSA), originally inspired by the simulation of collective behavior of real fish swarms, is proposed to fast and accurately extract the parameters of PV module. In addition to the regular operation, a mutation operator (MO) is designed to enhance the searching performance of the algorithm. The feasibility of the proposed method is demonstrated by various parameters of PV module under different environmental conditions, and the testing results are compared with other studied methods in terms of final solutions and computational time. The simulation results show that the proposed method is capable of obtaining higher parameters identification precision.

[A new puncture needle with multiple holes for testicular sperm extraction].

OBJECTIVE: To evaluate a new puncture needle with multiple holes (National Invention Patent of China: ZL 2010202466554) in testicular sperm extraction for infertile males. METHODS: This study included 215 azoospermia patients, who underwent testicular sperm extraction with a new puncture needle with multiple holes (group A, n = 133), by open biopsy (group B, n = 37), or with a fine needle (group C, n = 45). RESULTS: The first-time success rate was 100% in group A, 19% in B and 100% in C. The average operation time was obviously shorter in group A ([3 +/- 1] min) than in B ([15 +/- 3] min) and C ([7 +/- 2] min). The rate of postoperative complications was 3.0% in group A, significantly lower than in B (21.6%) and C (11.1%). CONCLUSION: The new puncture needle with multiple holes, with its advantages of accuracy, high first-time success rate, minimal invasiveness and low rate of complications, deserves to be generally applied in testicular sperm extraction.

[Comparison of three FOBT protocols for colorectal cancer screening in Chinese--a multicenter study].

OBJECTIVE: To evaluate three FOBT protocols of colorectal cancer screening. METHODS: A multycenter study was conducted based on a consulted program. The effectiveness/cost of each protocole (CFOBT, IFOBT, SFOBT) were evaluated by the identifying patients who underwent CFOBT and IFOBT for 3 times consecutively as well as colonoscopy. RESULTS: 323 eligible patients including 49 colorectal cancers, 60 colon adenomas, 60 chronic colitis, 15 hemorrhoids and 139 normal colon were observed. The effect/cost of CRC screening protocols was following: 1). For 3 times of FOBT consecutively: There was no significant difference for their sensitivity among CFOBT, IFOBT and SFOBT (95.9%, 95.9% & 93.9%) but the specificity of IFOBT and SFOBT (89.21% and 94.24%) were higher significantly than CFOBT (75.54%). The specificity of SFOBT was higher than IFOBT. After adjusting their detecting number of cancer to same level the cost of SFOBT was the lowest. among these FOBTs.2). For 2 times of FOBT consecutively: The sensitivity of CFOBT, IFOBT and SFOBT were 77.8%, 87.8% and 75.5% respectively. The sensitivity of IFOBT was higher than SFOBT and CFOBT significantly. Their specificity were 88.5%, 96.4% and 98.6% respectively. The specificity of IFOBT and SFOBT were higher significantly than CFOBT. However, there was no significant difference for the specificity between IFOBT and SFOBT. After adjusting their detecting number of cancer to same level the cost of IFOBT was the lowest. among these FOBTs.3). The detected rate of early colorectal cancer was 60% for all of 3 protocols. 4). 41.6% approximately 48.3% of adenomas was found by the 3 protocols, and 87.5% of adenomas over 2 cm in diameter were detected by any one of FOBT. CONCLUSIONS: For the population with nice compliance 3 times of SFOBT will be recommended as a screening protocol of colorectal cancer. For that with poor compliance 2 times of IFOBT was recommended 3. The majority of adenomas in that advanced lesion existed might be detected by FOBT.