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Interconnected multi-machine power system stabilizer design using whale optimization algorithm

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Protection and Control of Modern Power Systems 2019年第1期4卷 13-23页

作者： butti dasu Mangipudi Sivakumar Rayapudi Srinivasarao Gudlavalleru Engineering College GudlavalleruAndhra pradeshIndia JNTUK KakinadaAndhra pradeshIndia

The role of Power System Stabilizer (PSS) in the power system is to provide necessary damping torque to the system in order to suppress the oscillations caused by a variety of disturbances that occur frequently and maintain the stability of the system. In this paper, a PSS design technique is proposed using Whale Optimization Algorithm (WOA) by considering eigenvalue objective function. Two bench mark multi machine test systems: three- generator nine- bus system, two- area four- generator inter connected system working on various operating conditions are considered as case studies and tested with the proposed technique. Extensive simulation results are obtained and effectiveness of proposed WOA-PSS are compared with well - known PSO and DE based stabilizers under several disturbances.

关键词： Power system stabilizer Stability Whale optimization algorithm Dynamic performance Generators Eigenvalues

Temperature and pH Dependent Deactivation of Cutinases from Thermobifida fusca: A Comparative Study of Homologous Enzymes

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Modern Research in Catalysis 2014年第4期3卷 128-135页

作者： Krishnamoorthy Hegde Venkata dasu Veeranki Biochemical Engineering Laboratory Department of Biotechnology Indian Institute of Technology Guwahati Guwahati India

Thermostability of two homologous cutinases, Cut1 and Cut2 from Thermobifida fusca NRRL B-8184 was inves-tigated at combination of different pH and temperature in the range of pH 6 - 9 and temperature 45℃ - 80℃, re-spectively. The deactivation rate constants, the half-life and thermodynamic parameters, viz., △H*, △S*, △G* and activation energy kinetics of inactivation of the cutinases were assessed at different combinations of pH and temperature and compared. The optimal pH and temperature for the least degree of deactivation for Cut1 and Cut2 were found to be 8℃ and 45℃, respectively. The deactivation process was found to be faster at pH 6 and 9, with minimum deactivation at pH 8 for both the cutinases. It was found that △S* values are negative for both the enzymes and △H* value of Cut2 was 1.5 fold higher than that of Cut1 in the range of pH studied. Cut2 was found to be thermodynamically more stable with 1.7 fold higher deactivation energy at pH 6 and 7 and 1.4 fold higher deactivation energy at pH 8 and 9 in comparison to Cut1.

关键词： Cutinase Thermal Deactivation Thermostability Thermodynamics

Development of Medium and Kinetic Modeling for Enhanced Production of Cutinase from Pseudomonas cepacia NRRL B-2320

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Advances in Microbiology 2013年第6期3卷 479-489页

作者： Kasturi Dutta Veeranki Venkata dasu Krishnamoorthy Hegde Biochemical Engineering Laboratory Department of Biotechnology Indian Institute of Technology Guwahati Guwahati India

The development of medium for the production of cutinase from Pseudomonas cepacia NRRL B 2320 was carried out using Plackett-Burman experimental design followed by central composite design. The medium components were screened by Plackett-Burman experimental design which suggested that cutin, peptone, KCl and MgSO4·7H2O have influenced the cutinase production significantly with very high confidence levels. The concentration levels of these four components were optimized using 24 full factorial central composite design. An optimum combination of 10.06 g·L-1 of cutin, 17.77 g·L-1 of peptone, 0.635 g·L-1 of KCl and 5.455 g·L-1 of MgSO4·7H2O in the medium gave a maximum cutinase activity of 336 U·mL-1. An overall 2 fold increase in the production of cutinase was observed in the optimized medium. Growth and production of cutinase from P. cepacia NRRL B 2320 have been studied in shake flask and batch bioreactor. Time course of cell growth and enzyme production was fitted to the existing kinetic models reported in the literature to estimate the biokinetic parameters. These models suggested that the production of cutinase is growth associated in shake flask and it is a mixed growth type in a batch bioreactor.

关键词： Cutinase Kinetics Bioprocessing Optimization Parameter Identification

Toll-like receptor expression and signaling in human diabetic wounds

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World Journal of Diabetes 2014年第2期5卷 219-223页

作者： Mohan R dasu Sandra J Martin Department of Dermatology University of California at Davis McClellan Outpatient Clinic V A Northern California Health Care System

AIM: To examine the contribution of toll-like receptors(TLRs) expression and activation to the prolonged inflammation often seen in human diabetic ***: Debridement wound tissue was collected from diabetic patients with informed consent. Total RNA and protein were isolated and subjected to real-time polymerase chain reaction and Western blot analyses. RESULTS: TLR1, 2, 4, and 6 mRNA expressions were increased significantly in wounds of diabetic patients compared with non-diabetic wounds(P < 0.05). MyD88 protein expression was significantly increased in diabetic wounds compared to non-diabetic wounds. Interleukin-1beta, tumor necrosis factor-alpha concentration nuclear factor-kappa B activation, and thiobarbituric acid reactive substances were increased in diabetic wounds compared to non-diabetic wounds(P < 0.01). CONCLUSION: Collectively, our novel findings show that increased TLR expression, signaling, and activation may contribute to the hyper inflammation in the human diabetic wounds.

关键词： Interleukin-1β Inflammation Toll-like receptors 2 Toll-like receptors 4 Tumor necrosis factor-α Type 2-diabetes mellitus Wound healing

Batch, Fed Batch Production and Characterization of Glutaminase Free L-Asparaginase II of Pectobacterium carotovorumMTCC 1428 in Escherichia coli

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Advances in Microbiology 2014年第10期4卷 667-680页

作者： Rachna Goswami Krishnamoorthy Hegde Venkata dasu Veeranki Biochemical Engineering Laboratory Department of Biotechnology Indian Institute of Technology Guwahati Guwahati Assam India

The present study describes the production optimization of recombinant L-asparaginase II of Pectobacterium carotovorum MTCC 1428 in Escherichia coli BL21 (DE3) at batch and fed batch bioreactor level. Production of recombinant L-asparaginase II in batch and fed batch mode was found to be 1.34 and 5.38 folds higher, respectively as compared to shake flask culture. SDS-PAGE and native PAGE of the purified enzyme revealed that molecular mass of the subunits and native enzyme are ~37.5 kDa and ~150 kDa, respectively. Optimum range of pH and temperature for hydrolysis of L-asparagine were found to be 7.5 - 8.5 and 47°C - 52°C, respectively. The recombinant enzyme is very specific for its natural substrate, L-asparagine. The activity of recombinant L-asparaginase II is improved by mono cations and diverse effectors including Na+, K+, L-cystine, L-histidine, glutathione and 2-mercaptoethanol whereas, it is moderately inhibited by different divalent cations and thiol group blocking reagent. The kinetic parameters Km, Vmax, kcat and Km/Kcat of purified recombinant L-asparaginase II were determined. The purified L-asparaginase II possesses no partial glutaminase activity, which is prerequisite to reduce the possibility of side effects during the course of anti-cancer therapy.

关键词： Batch Fermentation Fed-Batch Fermentation Recombinant L-Asparaginase II Taguchi’s Method

CMS Level—1 Regional Calorimeter Trigger System

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International Conference on Computing in High Energy and Nuclear Physics 2001年第1期 632-635页

作者： P.Chumney S.dasu 等 UniversityofWisconsin－Madison

The CMS regional calorimeter trigger system detects signatures of electrons/photons,taus,jets,and missing and total transverse energy in a deadtinmess pipelined architecture .This system receives 7000 calorimeter tregger tower energies on 1.2 Gband digital copper cable serial links and processes them in a low-latency pipelined design using custom-built *** the heart of the system is the Receiver Card which uses the new generation of gigabit ethernet receiver chips on a mezzanine card to convert serial data to parallel data before transmission on a 160 MHz backplane for further processing by cards that sum energies and identify electrons and *** describe the algorithms and hardware implementation,and summarize the simulation results that show that this system is capable of handling the rate requirements while triggering on physics signals with high efficiency.

关键词： CMS实验热量计解发系统

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大规模数据挖掘中的数据流管理

中国科技资源导刊 2008年第6期40卷 30-38页

作者： Jon R.Wright Gregg T.Vesonder Tamraparni dasu 杨庆燕美国电话电报公司实验室-研究所美国新泽西州弗伦翰公园 079320971 清华大学计算机科学与技术系北京100084

在企业环境中,管理数据流或者实时数据更新是任何数据挖掘操作的一个主要挑战。无论是数据还是元数据,都要确保数据流的稳定、正确、可验。在这种环境下,实时数据更新很复杂,且数据量大而难懂。管理频繁变化的数据和元数据对企业是巨大... 详细信息

在企业环境中,管理数据流或者实时数据更新是任何数据挖掘操作的一个主要挑战。无论是数据还是元数据,都要确保数据流的稳定、正确、可验。在这种环境下,实时数据更新很复杂,且数据量大而难懂。管理频繁变化的数据和元数据对企业是巨大的挑战。本文阐述了在管理企业数据的任务中的技术问题,并提出了一种解决方法。这种解决方法可以结合多个领域里的知识,如工程技术和统计学,来理解和标准化企业挖掘的准备工作,以使信息采集和质量管理自动化。

关键词：信息质量数据挖掘传送管理知识工程

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民国时期旅渝者的重庆旅游意象研究

重庆三峡学院学报 2015年第2期31卷 36-40,57页

作者：吴大素西南大学西南历史地理研究所重庆北碚400715

民国时期的重庆,在20世纪30年代之前,基本处于国人视角的边缘位置,被外界视为蛮荒之地。30年代后的重庆逐渐进入大众视野,作为抗战陪都,大批川外人士入驻重庆,重庆一时成为国人舆论核心。根据民国时期来渝旅行的游记和文人笔记小说资料... 详细信息

民国时期的重庆,在20世纪30年代之前,基本处于国人视角的边缘位置,被外界视为蛮荒之地。30年代后的重庆逐渐进入大众视野,作为抗战陪都,大批川外人士入驻重庆,重庆一时成为国人舆论核心。根据民国时期来渝旅行的游记和文人笔记小说资料,窥视当时来渝旅行者对重庆的旅游意象和地域评价,发现旅客对重庆意象要素不断丰满全面,由负面认知逐渐向积极正面转变。因时代赋予的"民族复兴根据地"使得民国时期的重庆旅游意象具有激昂的民族情感。

关键词：民国游记重庆旅游意象

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操作参数对Corex铁水Si含量的影响

世界钢铁 2010年第1期10卷 1-6+18页

作者： P Prachethan Kumar A V R P dasu M Ranjan T K Naha 张海洋金达尔钢公司研发部

优质低耗的钢铁产品需求低硅低硫的优质铁水。高硅铁水是炼钢处理所不希望的,它导致处理流程成本增加、产率降低,因此,需持续努力降低铁水中Si的含量。Corex是唯一确立并被证明已成功商业运行的改变传统高炉炼铁的熔融还原技术。尽管高... 详细信息

优质低耗的钢铁产品需求低硅低硫的优质铁水。高硅铁水是炼钢处理所不希望的,它导致处理流程成本增加、产率降低,因此,需持续努力降低铁水中Si的含量。Corex是唯一确立并被证明已成功商业运行的改变传统高炉炼铁的熔融还原技术。尽管高炉硅转移原理已被熟练掌握,但Corex工艺仍然需要进一步的操作指导来控制硅转移。对超过一年的工厂运行数据进行统计分析,可以了解铁水中Si含量的影响因素,提供预测和控制铁水Si含量的方法。用回归分析得出回归方程来预测Corex铁水Si含量。简要讨论了硅预测回归分析中所涉及的各种因素,并验证操作参数,阐述了各参数间的相互关系。数据分析表明高水分、低金属化率、高挥发分、高渣比、高煤粉率、低产能直接导致高燃料比,同时炉渣高碱度和高Al2O3含量会导致铁水Si含量升高。

关键词： Corex 燃料比灰分硅炉渣高炉熔融气化炉还原竖炉