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Journal of Chemistry and Chemical Engineering 2016年第5期10卷 207-211页

作者： Ganna Lyubartseva Sean Parkin Shamiso Ngongoni uma prasad Mallik Department of Biochemistry and Chemistry Southern Arkansas University Magnolia AR 71753 USA Department of Chemistry University of Kentucky Lexington KY40506 USA Department of Engineering and Physics Southern Arkansas University Magnolia AR 71753 USA

Bis[1-methoxy-2,2,2-tris-（pyrazol-l-yl-KN2）ethane]-copper（Ⅱ） bis-perchlorate （2） was synthesized by reacting of pyrazole based tripodal scorpionate ligand 1-methoxy-2,2,2-tris（pyrazol-1-yl）ethane （1） with copper（Ⅱ） perchlorate hexahydrate in methanol, acetonitrile and water mixture as solvent. Slow evaporation of the filtered reaction mixture in air produced blue color block crystals suitable for single crystal X-ray diffraction study of the title complex. Compound 2 crystallizes in the monoclinic space group P21/n with unit cell parameters, α = 8.1269（1） ,A, b = 21.8348（2）A, c = 9.1522（1） A, a = γ= 90° , β = 99.7611 （4）°. The structure of the compound was characterized by IR Spectroscopy, elemental analysis and single crystal X-ray diffraction analysis.

关键词： Pyrazole tripodal ligand scorpionate ligand single crystal X-ray diffraction.

3D and 2D topographic correction to estimated geothermal gradient from the base of gas hydrate stability zone in the Andaman Forearc Basin

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Energy Geoscience 2024年第2期5卷 314-320页

作者： uma Shankar Department of Geophysics Institute of ScienceBHUVaranasiIndia

Methane gas hydrate related bottom-simulating reflectors(BSRs)are imaged based on the in-line and cross-line multi-channel seismic(MCS)data from the Andaman Forearc *** depth of the BSR depends on pressure and temperature and pore water *** these assumptions,the BSR depth can be used to estimate the geothermal gradient(GTG)based on the availability of in-situ temperature *** calculation is done assuming a 1D conductive model based on available in-situ temperature measurement at site NGHP-01-17 in the study ***,in the presence of seafloor topography,the conductive temperature field in the subsurface is affected by lateral refraction of heat,which focuses heat in topographic lows and away from topographic *** 1D estimate of GTG in the Andaman Forearc Basin has been validated by drilling results from the NGHP-01 expedition.2D analytic modeling to estimate the effects of topography is performed earlier along selected seismic profiles in the study *** study extended to estimate the effect of topography in 3D using a numerical *** corrected GTG data allow us to determine GTG values free of topographic *** difference between the estimated GTG and values corrected for the 3D topographic effect varies up to~5℃/*** conclude that the topographic correction is relatively small compared to other uncertainties in the 1D model and that apparent GTG determined with the 1D model captures the major features,although the correction is needed prior to interpreting subtle features of the derived GTG maps.

关键词： Gas hydrate BSR Geothermal gradient 3D and 2D topographic modeling Andaman Forearc Basin

An Adaptive Scalable Data Pipeline for Multiclass Attack Classification in Large-Scale IoT Networks

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Big Data Mining and Analytics 2024年第2期7卷 500-511页

作者： Selvam Saravanan uma Maheswari Balasubramanian Department of Computer Science and Engineering Amrita School of ComputingAmrita Vishwa VidyapeethamBengaluru 560035India

The current large-scale Internet of Things(IoT)networks typically generate high-velocity network traffic *** use IoT devices to create botnets and launch attacks,such as DDoS,Spamming,Cryptocurrency mining,Phishing,*** service providers of large-scale IoT networks need to set up a data pipeline to collect the vast network traffic data from the IoT devices,store it,analyze it,and report the malicious IoT devices and types of ***,the attacks originating from IoT devices are dynamic,as attackers launch one kind of attack at one time and another kind of attack at another *** number of attacks and benign instances also vary from time to *** phenomenon of change in attack patterns is called concept ***,the attack detection system must learn continuously from the ever-changing real-time attack patterns in large-scale IoT network *** meet this requirement,in this work,we propose a data pipeline with Apache Kafka,Apache Spark structured streaming,and MongoDB that can adapt to the ever-changing attack patterns in real time and classify attacks in large-scale IoT *** concept drift is detected,the proposed system retrains the classifier with the instances that cause the drift and a representative subsample instances from the previous training of the *** proposed approach is evaluated with the latest dataset,IoT23,which consists of benign and several attack instances from various IoT *** classification accuracy is improved from 97.8%to 99.46%by the proposed *** training time of distributed random forest algorithm is also studied by varying the number of cores in Apache Spark environment.

关键词： Internet of Things(IoT) concept drift Apache Spark MongoDB Apache Kafka streaming

Design of Power System Stabilizer for DFIG-based Wind Energy Integrated Power Systems Under Combined Influence of PLL and Virtual Inertia Controller

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Journal of Modern Power Systems and Clean Energy 2024年第2期12卷 524-534页

作者： Balakrushna Sahu Bibhu prasad Padhy Department of Electrical Engineering Indian Institute of Technology RoparPunjab140001India

Wind energy systems (WESs) based on doubly-fed induction generators (DFIGs) have enormous potential for meeting the future demands related to clean energy. Due to the low inertia and intermittency of power injection, a WES is equipped with a virtual inertial controller (VIC) to support the system during a frequency deviation event. The frequency deviation measured by a phase locked loop (PLL) installed on a point of common coupling (PCC) bus is the input signal to the VIC. However, a VIC with an improper inertial gain could deteriorate the damping of the power system, which may lead to instability. To address this issue, a mathematical formulation for calculating the synchronizing and damping torque coefficients of a WES-integrated single-machine infinite bus (SMIB) system while considering PLL and VIC dynamics is proposed in this paper. In addition, a power system stabilizer (PSS) is designed for wind energy integrated power systems to enhance electromechanical oscillation damping. A small-signal stability assessment is performed using the infinite bus connected to a synchronous generator of higher-order dynamics integrated with a VIC-equipped WES. Finally, the performance and robustness of the proposed PSS is demonstrated through time-domain simulation in SMIB and nine-bus test systems integrated with WES under several case studies.

关键词： Doubly-fed induction generator(DFIG) virtual inertia controller(VIC) phase locked loop(PLL) small-signal analysis synchronizing/damping torque synchronous generator power system stabilizer(PSS)

A Pair of Pseudo-differential Operators Involving Index Whittaker Transform in L_(2)^(a) (R_(+);m_(a)(x)dx)

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Acta Mathematica Sinica,English Series 2024年第6期40卷 1420-1430页

作者： Jeetendrasingh MAAN Akhilesh prasad Department of Mathematics and Computing Indian Institute of Technology(Indian School of Mines)Dhanbad-826004India

Pseudo-differential operators(PDO)Q(x,L_(a,x))and Q(x,L_(a,x))involving the index Whittaker transform are *** for these operators in Hilbert space L_(2)^(a)(R+;m_(a)(x)dx)are obtained.A symbol classΩis *** product an... 详细信息

关键词： Pseudo-differential operator index Whittaker transform confluent hypergeometric functions Hilbert space

A novel control strategy of a variable-speed doubly-fed-induction-generator-based wind energy conversion system

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Clean Energy 2024年第1期8卷 153-170页

作者： Shibani prasad Mohapatra Pradipta Kishore Dash Department of Electrical Engineering Siksha O Anusandhan Deemed to be UniversityBhubaneswar-751030OdishaIndia Multidisciplinary Research Cell Siksha O Anusandhan Deemed to be UniversityBhubaneswar-751030OdishaIndia

This paper aims to address the issue of control of a variable-speed wind turbine based on doubly-fed induction generators. In this work,an effort is made to extract the maximum efficiency from a doubly-fed induction generator-based variable-speed wind turbine by controlling the rotor current. In the first step, a maximum power point tracking technique is used to extract the maximum power from theturbine. Then a stator-flux-oriented vector control strategy is employed to control the rotor-side current. Subsequently, a grid voltagevector-oriented control strategy is used to control the grid-side system of the grid-connected generator. Considering the nonlinearityand parameter uncertainty of the system, an active disturbance rejection controller with a sliding-mode-based extended-state observeris developed for the above-mentioned control strategies. Furthermore, the stability of the controller is tested and the performance of thecontroller is compared with the classical proportional-integral controller based on disturbance rejection, robustness and tracking capability in a highly non-linear wind speed variation scenario. Modelling, control and comparison are conducted in the MATLAB®/Simulink®environment. Finally, a real-time hardware set-up is presented using the dSPACE ds-1104 R&D processing board to validate the controlscheme. From the result of the experiments, it is seen that the proposed controller takes 10-15 control cycles to settle to its steady-statevalues, depending on the control loop, whereas the conventional proportional-integral controller takes 60-75 control cycles. As a result,the settling time for the proposed control scheme is shorter than that of the proportional-integral controller.

关键词： doubly-fed induction generator variable-speed wind turbine vector control active disturbance rejection controller stability analysis

Gas hydrate saturation from NGHP 02 LWD data in the Mahanadi Basin

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Energy Geoscience 2024年第2期5卷 279-289页

作者： uma Shankar Pradeep Kumar Yadav Sneha Devi Udham Singh Yadav Department of Geophysics Institute of ScienceBHUVaranasi221005India Oil and Natural Gas Corporation Ltd. Gas Hydrate Research&Technology Centre(GHRTC)Panvel410221Navi MumbaiIndia

During the Indian National Gas Hydrate Program(NGHP)Expedition 02,Logging-while-drilling(LWD)logs were acquired at three sites(NGHP-02-11,NGHP-02-12,and NGHP-02-13)across the Mahanadi Basin in area *** applied rock physics theory to available sonic velocity logs to know the distribution of gas hydrate at site NGHP-02-11 and *** physics modeling using sonic velocity at well location shows that gas hydrate is distributed mainly within the depth intervals of 150-265 m and 100 -215 mbsf at site NGHP-02-11 and NGHP-02-13,respectively,with an average saturation of about 4%of the pore space and the maximum concentration of about 40%of the pore space at 250 m depth at site NGHP-02-11,and at site NGHP-02-13 an average saturation of about 2%of the pore space and the maximum concentration of about 20%of the pore space at 246 m depth,as gas hydrate is distributed mainly within 100-246 mbsf at this *** of gas hydrate estimated from the electrical resistivity method using density derived porosity and electrical resistivity logs from Archie's empirical formula shows high saturation compared to that from the sonic ***,estimates of hydrate saturation based on sonic P-wave velocity may differ significantly from that based on resistivity,because gas and hydrate have higher resistivity than conductive pore fluid and sonic P-wave velocity shows strong effect on gas hydrate as a small amount of gas reduces the velocity significantly while increasing velocity due to the presence of *** site NGHP-02-11,gas hydrate saturation is in the range of 15%e30%,in two zones between 150-180 and 245-265 *** NGHP-02-012 shows a gas hydrate saturation of 20%e30%in the zone between 100 and 207 *** NGHP-02-13 shows a gas hydrate saturation up to 30%in the zone between 215 and 246 *** observations from rock physics modeling and Archie’s approximation show the gas hydrate concentrations are relatively low(<4%of the pore space)at the sites of the

关键词： Mahanadi Basin Gas hydrate Sonic log Effective medium modeling Electrical resistivity log Archie’s analysis Gas hydrate saturation

Liver transplantation as an alternative for the treatment of non-resectable liver colorectal cancer: Advancing the therapeutic algorithm

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Hepatobiliary & Pancreatic Diseases International 2024年第2期23卷 154-159页

作者： Badi Rawashdeh Richard Bell Abdul Hakeem Raj prasad Division of Transplant Surgery Department of General SurgeryMedical College of WisconsinMilwaukeeWI53226USA Leeds Teaching Hospital LeedsUK

Colorectal cancer is a leading cause of cancerrelated mortality,with nearly half of the affected patients developing liver *** three decades,liver resection(LR)has been the primary curative strategy,yet its applicability is limited to about 20%of *** transplantation(LT)for unresectable metastases was attempted unsuccessfully in the 1990s,with high rates of perioperative death and *** is now more interest in this strategy due to improvements in systemic therapies and surgical techniques.A significant study conducted by the Oslo group showed that patients receiving liver transplants had a 60%chance of survival after five *** better results have been achieved by using advanced imaging for risk stratification and further refining selection criteria,especially in the Norvegian SECA *** review carefully charts the development and history of LT as a treatment option for colorectal cancer liver *** revolutionary path from the early days of exploratory surgery to the current situation of cautious optimism is traced,highlighting the critical clinical developments and improved patient selection standards that have made LT a potentially curative treatment for such challenging very well selected cases.

关键词： Liver transplantation Colorectal cancer liver metastases Non-resectable liver metastases

Exploring the Social Impact of the Short-Stay Market(SSM)in Regional Areas:An Empirical Study

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Fudan Journal of the Humanities and Social Sciences 2024年第2期17卷 243-277页

作者： Emeka Ndaguba Kerry Brown Dora Marinova uma Jogulu School of Business and Law Edith Cowan UniversityPerthAustralia Curtin University Sustainability Policy Institute Curtin UniversityPerthAustralia

The discourse on microentrepreneurs and their involvement in the short stay market (SSM) was non-existent until 2008. While several concepts and constructs have been developed and empirically tested since 2009, many of them relate to economics, leaving the social, cultural, and environmental factors underdeveloped. Thus, this study aimed to fll the gap and identify and assess the social impact of the short-stay market (SSM) in a regional area. The study included 16 face-to-face interview sessions conducted with 18 participants, and the Leximancer software was employed to analyse the data. The study revealed that the social impact on SSM is not generic, rather pluralistic, multidimensional, and dynamic. The study also found that the limitation clause instituted by the council is a direct disconnect between the council and property owners/managers. Furthermore, despite ample opportunities provided by the short-stay market (SSM) in regional areas, encumbrances cannot be overlooked. Therefore, there is a need for a comprehensive approach to understand the social impact on policy frameworks in regional areas.

关键词： Short-stay market Experience economy Long-term rentals Wine economy Regulation

Expert perspective on technological choice for cooking energy transition in Nepal

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Clean Energy 2024年第4期8卷 40-48页

作者： Dipesh KC Sunil prasad Lohani Poushan Shrestha Chunyu Xue Renewable and Sustainable Energy Laboratory(RSEL) Department of Mechanical EngineeringKathmandu UniversityKathmanduNepal Biomass Energy and Environmental Engineering Research Center Beijing University of Chemical TechnologyBeijingChina

Solid biomass dominates as the primary source of cooking energy,especially in rural households of *** use of solid biomass has a detrimental effect on health,exacerbates the burden of biomass collection,and hampers access to clean *** the factors influencing the choice of modern cooking fuels is crucial to improving energy security and resilience and easing the transition to clean *** study evaluates technological choices for the transition in cooking energy from the perspective of experts working in the government,non-government,and academia sectors.A structured questionnaire survey was prepared with five criteria and nine cooking technology ***-one experts responded to the survey,and their responses were analyzed using the analytical hierarchy *** study reveals that efficiency and capital cost are the primary criteria for selecting cooking tech*** most suitable clean cooking technology is an induction stove followed by a hot plate,while the least preferred technology is a Bayupankhi stove followed by two-pothole mud improved cooking *** ensure the robustness of the method,sensitivity analysis was performed on the two primary criteria efficiency and capital cost of the cooking *** analysis revealed robust and consistent rankings of *** study should help create a conducive environment for relevant stakeholders and policymakers to formulate and implement relevant policies and strategies to accelerate the cooking energy transition in Nepal.

关键词： cooking technologies cooking energy transition electric cooking residential sector analytical hierarchy process