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考虑故障电流限制器与柔性交流输电系统的分布式电源低电压穿越效率提升方法研究

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考虑故障电流限制器与柔性交流输电系统的分布式电源低电压穿越效...

作者： farooq muhammad 华北电力大学(北京)

学位级别：硕士

风力发电(WPG)是能够产生电力以满足能源需求的最先进技术之一。随着机械设备的发展,基于双馈感应发电机(DFIG)的风力涡轮机得到了很大的改进。使用基于双馈感应发电机的风力涡轮机的主要优点是它们使电力系统的运行更加可靠,另外使用... 详细信息

风力发电(WPG)是能够产生电力以满足能源需求的最先进技术之一。随着机械设备的发展,基于双馈感应发电机(DFIG)的风力涡轮机得到了很大的改进。使用基于双馈感应发电机的风力涡轮机的主要优点是它们使电力系统的运行更加可靠,另外使用双馈感应发电机可在较宽范围内的转子速度下运行,并且可以减少变流器承载的功率量,从而显着降低变流器成本。目前,电力系统中有许多设备作用于提高系统稳定性并降低预期的高故障电流,包括断路器、熔断器、串联电抗器和高阻抗变压器,然而,这些传统设备在反应速度、功率损耗和系统稳定性反面存在难题。本节介绍了一些用于提高电力系统可靠性的新器件,例如超导故障电流限制器(SFCL)、FACTS器件和电力系统稳定器(PSS)。本文讨论了使用基于双馈感应发电机的风力涡轮机并网时面临的稳定性问题以及使用上述系统的分布式发电的稳定性损失问题。研究的主要目的是使用超导故障电流限制器(SFCL)和柔性交流输电系统(FACTS)设备解决低电压穿越(LVRT)和其他稳定性问题。根据实验结果表明超导故障电流限制器不仅提高了双馈感应发电机的解决低电压穿越能力,而且还改善了双馈感应发电机在电网故障情况下的动态行为。报告数据有助于将电网的柔性交流输电系统商业化,还可以观察到不同类型的PSS对并网风能系统稳定性的影。最后的结果验证了所提方法的有效性。为了观察FACTS器件对LVRT能力的影响,引入了与故障阻抗串联的远程故障,它在PCC处产生32%的电压骤降,即0.68pu。使用STATCOM电压提高到0.76pu,而使用SVC电压提高到 0.74pu。

关键词：低电压穿越能力 WECS-SFCL 带有FACTS设备的WECS 分布式发电(DG) 多机系统稳定性的PSS

Vegetative Development of <i>Sparassis crispa</i>in Various Growth Conditions and Effect of Electric Pulse Simulation on Its Fruit Body Production

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Advances in Microbiology 2014年第5期4卷 267-274页

作者： muhammad Umar farooq Alfred Chioza, Shoji Ohga Department of Agro-Environmental Sciences Faculty of Agriculture Kyushu University Fukuoka Japan

This study was carried out to detect the favorable mycelial growth conditions and effect of electric pulse stimulation on fruit body production of SC-1 strain of Sparassis crispa. The optimum growth in PDA was found at 25°C (67 mm colony diameter in 28 days) followed by 20°C (63 mm colony diameter in 28 days). There was no mycelial growth at 35°C. The most favourable initial media pH range was found to be 5 - 7 and colony diameter measurements were not statistically different among these pH values (p > 0.05). However, the highest growth was obtained at pH 6 (57 mm colony diameter in 28 days). A basal medium composed of 0.05 g MgSO4, 0.46 g KH2PO4, 1.0 g K2HPO4, 120 μg thiamine-HCl, 20 g agar and 1000 ml of distilled water was used to investigate growth response of S. crispato different carbon and nitrogen sources. In 28 days, fructose and glucose exhibited best growth (49.4 mm and 31.6 mm colony diameters respectively) and there was no growth on the basal medium supplemented with galactose. Basal medium supplemented with glycine and alanine as nitrogen sources resulted in best growth, 54.4 mm and 50.5 mm colony diameters respectively. There was no mycelial growth in culture medium supplemented with ammonium acetate, ammonium phosphate, arginine and histidine. Electric pulse stimulation improved the fruiting body production. The yields obtained from all bottles in which electric pulse was applied were significantly higher than the yields from the bottles in which electric pulse was not applied. The percent increases of fresh weight yield from control on 100, 120, 130, and 170 kilovolts were 36%, 44%, 75% and 81% respectively. As regard to dry weight yield, the percent increases from control on 100, 120, 130, and 170 kilovolts were 27%, 54%, 63% and 67% respectively.

关键词： Sparassis crispa Fruit Body Production Mycelial Growth Electric Pulse Stimulation

Impact of Processing Conditions on the Milk Clotting Activity of Crude Protease Extracted from Chinese Ginger

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Impact of Processing Conditions on the Milk Clotting Activit...

Attraction of <i>Idioscopus clypealis</i>(Leith) (Cicadellidae: Homoptera) to Sticky Colored Traps in Mango Orchard

International Conference on Food Engineering and Biotechnology（ICFEB 2011）

作者： Malik muhammad Hashim muhammad farooq Iqbal College of Food Science and Technology Nanjing Agricultural UniversityNanjing 210095China Faculty of Veterinary and Animal Sciences Arid Agricultural UniversityRawalpindiPakistan

The impact of three processing parameters namely homogenization time,pH of buffer,and amount of buffer,involved in the liquid extraction of proteinases from ginger rhizomes,was investigated on milk coagulating activity by response surface *** empirical quadratic model was applied to experimental data pertaining to the average enzymatic activity and equation describing the optimal conditions was *** maximum milk clotting activity（274 U/mL） was obtained by homogenizing the ginger rhizomes in 76 mL of extraction buffer with a pH of 7.0 for 2.4 *** significant（p ＞ 0.05） difference was observed between the experimental and predicted *** results are useful in the optimization of extraction procedures,which are of significant relevance to the production of standardized plant coagulants suitable for the cheese industry.

关键词： Ginger protease Plant coagulant Response surface methodology

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American Journal of Plant Sciences 2013年第11期4卷 2275-2279页

作者： Shafqat Saeed muhammad Abrar Amin Qamar Saeed muhammad farooq Department of Entomology Faculty of Agricultural Sciences and Tech-nology Bahauddin Zakariya University Multan Pakistan Directorate of Quality Enhancement Bahauddin Zakariya University Multan Pakistan

The present study was conducted at the Faiz Chaman mango orchard, Multan to find out the attraction of mango hopper Idioscopus clypealis to sticky traps of different colors. The experiment was laid out in randomized complete block designed with three replications. The sticky traps were hung vertically with the branch/twig under the canopy of mango trees. Data were recorded under binocular stereoscope. Results indicated significant differences in the number of I. clypealis (adults) captured in the different colored sticky traps. Yellow color was found most attractive with a capture of highest number of adults of I. clypealis (11.53 adults/trap). While pink and purple colors were found less attractive. The peak population of mango hoppers was recorded at the 31.96°C during 25-April to 9-May. Yellow sticky traps were found most effective in trapping a considerably higher number of hoppers throughout the study period. Correlation analysis revealed a strong positive correlation between temperature and the mean number of I. clypealis adults. Population peaks of I. clypealis were recorded at temperatures >30°C, while at lower temperatures relatively low numbers of adults were recorded.

关键词： Mango Hoppers Sticky Colored Traps Mango Attraction Idioscopus clypealis

Decentralized Power Control Strategy in Microgrid for Smart Homes

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Smart Grid and Renewable Energy 2019年第3期10卷 43-53页

作者： Manzar Ahmed Asif Nawaz Mishaal Ahmed muhammad Shoaib farooq Punjab Institute of Complementary Sciences Lahore Pakistan Higher College of Technology Dubai UAE University of Technology & Management Lahore Pakistan

In this paper, Nanogrid System and working is presented for the future sustainable power system. This system is for small scale for smart homes with decentralized power system. A Nanogrid is the combination of energy system such as using of sources such as solar cells, fuel cells, micro turbines, wind turbines, energy storage devices and AC, DC power systems and controllable loads. This grid may use single mode or island mode with soft switching. The Dynamic of power system capability increases reliability, in case if one system fails it switch to other system to continue proving electric power with losing quality. The energy storage system is used to maintain stability during transition between the operating modes is emphasized. The Simulink model is used to present the working of system.

关键词： Microgrid Distributed Generation (DG) Load Sharing In-Landing and n Gird

巴基斯坦萨戈达地区危害桔园的桃实蝇时空分布（英文）

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昆虫学报 2017年第12期60卷 1457-1466页

作者： muhammad ARIF muhammad SIDDIQUE AASI muhammad farooq Habib ALI Saif UL ISLAM muhammad ASAD muhammad SHAKEEL 吴祖建福建农林大学植物保护学院福州350002 Department of Pest Warning and Quality Control of Pesticides District Sargodha Cotton Research Station FaisalabadPakistan 华南农业大学农学院广州510642

【目的】本研究旨在监测2009-2011年Tehsil Sargodha 7个地点(Sargodha-Ⅰ,Sargodha-Ⅱ,Bhagtanwala,Sakessar,Chak#75-SB,Chak#46-SB和Chak#104-NB)中桃实蝇Bactrocera zonata优势种的种群变化情况。【方法】通过甲基丁香酚信息素诱捕器诱捕桃实蝇,每周统计记录桃实蝇种群发生情况,诱捕器每两周加药一次。【结果】结果表明,在调查的3年(2009-2011)中,Sargodha-Ⅰ的桃实蝇种群多度最高(分别为53.67,45.82和45.47头/诱捕器),其次为Sakessar(分别为41.13,33.87和35.75头/诱捕器),而Chak#75-SB的种群多度最低(分别为15.78,19.18和19.15头/诱捕器)。每年桃实蝇发生最高峰出现在4月(分别为76.08,71.94和61.51头/诱捕器),其次为5月(分别为60.74,52.63和64.00头/诱捕器),而在2月和10月发生量最低。另外,桃实蝇种群多度与最高和最低气温呈较强的正相关,而与相对湿度和降雨量呈负相关。同样,回归系数表明,最高气温是影响桃实蝇种群发生的主要因素,而降雨量的影响最小。【结论】应当全年对桃实蝇进行定期监测,由于气象因子严重影响桃实蝇的种群发生情况,因此尤其应监测其在4-5月温度开始上升时的发生情况。

关键词：实蝇科桃实蝇种群动态气象因子柑橘信息素诱捕器

Identification and Characterization of Bacterial Community Associated with the Chewed Feeding Waste of Red Palm Weevil in Infested Date Palm Trees

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Advances in Bioscience and Biotechnology 2020年第3期11卷 80-93页

作者： AbdulAziz M. A. Mohamed muhammad farooq Malabika Roy Pathak Agricultural Biotechnology Program Department of Life Sciences Arabian Gulf University Manama Kingdom of Bahrain Agricultue Affairs Ministry of Works Municipalities Affairs and Urban Planning Manama Kingdom of Bahrain.

Red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier) (Coleoptera, Curculionidae), is considered one of the most damaging insect pests of date palms in the Kingdom of Bahrain. Large scale infestation of RPW to date palm trees leads to excessive feeding activity of the RPW larvae, which is carried out by microorganisms present within RPW and producing a wet fermenting material inside the trunk. Culture dependent-bacteria were isolated from feeding waste and identified by the sequencing of the 16S rRNA gene using 8F and 1492R universal primers. Among the culture-dependent isolated bacteria, 80% were identified by comparing 16S rRNA gene sequence in NCBI database, using BLAST program in GenBank. 85% of the identified bacteria were Gram-positive while the rest of them were Gram-negative. A high abundance of bacteria were from the Bacillaceae family and sixteen different species of Bacillus were identified in comparison with NCBI GenBank. The 16S rRNA gene sequences of identified bacterial strains have been submitted to GenBank. The phylogenetic relationship was studied using 16S rRNA gene sequences, the Gram-negative bacteria came in one clade while Gram-positive different Bacillus sp. and strains showed evolutionary closeness to each other and accordingly, they came in one major clade under three different sub-clades in the phylogenetic tree. The findings of new Bacillus strains in the natural habitat of the date plam trees in the Kingdom of Bahrain, pledge a vast area of research on RPW bio-control research arena.

关键词： Red Palm Weevil (RPW) Bacteria Date Palm Feeding Waste 16S rRNA

Role of Canal Lining on Groundwater Fluctuations: A Modeling Simulation Approach for Jaalwala Distributary, Bahawalnagar

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Open Journal of Applied Sciences 2017年第5期7卷 213-232页

作者： muhammad Hammad Atique Khan muhammad Usman Saleem Sajid Rashid Ahmad Nasir Ahmad Shahid Jamil Sameeni muhammad Akram muhammad farooq Institute of Geology University of the Punjab Lahore Pakistan Collage of Earth and Environmental Sciences University of the Punjab Lahore Pakistan Irrigation Department Government of Pakistan Lahore Pakistan

Jaalwala Distributary was selected to see the consequences of concrete lining on the underlying saline groundwater table. Its middle and tail portions were concrete lined whereas the head portion was still unlined. Visual MODFLOW 2011.1 was used to simulate the effects of concrete lining on saline groundwater in two-dimensional format. Simulation results showed a gradual rise of electrical conductivity (EC) up to 7000 μS/cm and decline in water table depth to nine feet (2.74 m). It observed negligible inflows from the distributary through its western boundary due to formation of a permanent barrier in the way of seepage of any kind. Results have further predicted that freshwater layer available beneath the Jaalwala Distributary (before its lining) will finish ultimately and the below present saline water also move upward to take this vacated place. Hence it was concluded to line the canals of saline water areas from their sides which will not only protect them from erosion but canal water theft as well.

关键词： Water Balance Jaalwala Distributary Saline Water Intrusion Hydrostatic Pressure and Interface

DNA Barcoding and Identification of Medicinal Plants in the Kingdom of Bahrain

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American Journal of Plant Sciences 2018年第13期9卷 2757-2774页

作者： Malabika Roy Pathak Abdulaziz A. M. Mohamed muhammad farooq Department of Life Sciences Arabian Gulf University Manama Kingdom of Bahrain Ministry of Works and Municipalities Affairs and Urban Planning Manama Kingdom of Bahrain

Authentication of medicinally important plants is essential for increasingly demands of herbal remedies worldwide. DNA barcoding technology is currently gaining importance as a reliable tool for plant species identification, although one barcode gene is not enough in the exceptions. Short sequence diversity of standardized specific coding gene regions of rbcLa and matK of plastid genome together with noncoding ribosomal internal transcribed spacer 2 (ITS2) marker is used as barcode to compare and differentiate plant species. The success of obtaining sequences of the 29 analyzed plants distributed in 21 families using three different barcode genes rbcLa, matK and ITS2 were 97%, 79% and 75% respectively. Multiple sequence alignment confirmed the medicinal plants at species level by 89.28%, 86.32% and 60.86% obtained through rbcLa, ITS2 and matK barcodes sequences respectively. The genetic distance between sequence pairs (GD) and percentage identity (PI) is compared to analyze the plant identity at species level. The phylogenic trees constructed to show the relatedness and distance of the analyzed plants in the history of evolution by the analysis of richness of clades. The construction of DNA barcode library of desert medicinal plants is an introductory research arena in Kingdom of Bahrain in helping the routine identification of plants, and developing guidelines for detection of adulterants in herbal medicines as well as protection of biodiversity.

关键词： DNA Barcode Medicinal Plants Phylogenetic Tree Species Identification