检索结果-南通市图书馆

Decentralized Primary Frequency Regulation for Hybrid Multi-terminal Direct Current Power Systems Considering Multi-source Enhancement

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第3期12卷 958-970页

作者： Jialiang Wu Zhen Wang Ruixu Liu Yu Shan Chenxuan Wang the college of Electrical Engineering Zhejiang UniversityHangzhou 310027China the economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China

Hybrid multi-terminal direct current(MTDC)transmission technology has been a research focus,and primary frequency regulation(FR)improvement in the receiving-end system is one of the problems to be *** paper presents a decentralized primary FR scheme for hybrid MTDC power systems considering multi-source enhancement to help suppress frequency disturbance in the receiving-end *** the converters only need local frequency or DC voltage signal input to respond to system disturbance without communication or a control center,i.e.,a decentralized control *** proposed scheme can activate appropriate power sources to assist in FR in various system disturbance severities with fine-designed thresholds,ensuring sufficient utilization of each power *** better balance FR performance and FR resource participation,an evaluation index is proposed and the parameter optimization problem is further ***,the validity of the proposed scheme is verified by simulations in MATLAB/Simulink.

关键词： Decentralized control scheme primary frequency regulation(FR) rate of change of frequency(ROCOF) system frequency disturbance

A Structural Measurement of the Valuation Effect of China's External Assets:Method and Application

在线全文

学校读者我要写书评

暂无评论

China & World Economy 2024年第2期32卷 97-124页

作者： Guowei Cai Xiaowei Chen Xun Wang Lingnan college Sun Yat-sen UniversityChina China Center for economic Research National School of DevelopmentPeking UniversityChina

Existing research on the measurement of the valuation effect mainly follows the residual method proposed by Lane and Milesi-Ferretti(2001).This cannot be used to perform structural *** propose an aggregation approach rather than the residual method to measure structurally the investment flow and valuation effect of China's external *** results indicate that the valuation effect of China's external assets has been highly volatile and it was negative during the pandemic *** structural decomposition shows that portfolio investment and direct investment made the main contributions to the valuation *** impact of exchange rates on the valuation effect has generally been higher than that of asset price in terms of direct investment and total external assets but the opposite has been true for portfolio ***'s outward investments are currently more inclined to Asian countries and a few European countries but inflows to China still mainly come from developed countries.

关键词： external asset investment direction structural measurement valuation effect

Modeling the dynamical behavior of the interaction of T-cells and human immunodeficiency virus with saturated incidence

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications in Theoretical Physics 2024年第3期76卷 1-14页

作者： Salah Boulaaras Rashid Jan Amin Khan Ali Allahem Imtiaz Ahmad Salma Bahramand Department of mathematics College of ScienceQassim UniversityBuraydah51452Saudi Arabia Institute of Energy Infrastructure(IEI) Department of Civil EngineeringCollege of EngineeringUniversiti Tenaga Nasional(UNITEN)Putrajaya CampusJalan IKRAM-UNITEN43000 KajangSelangorMalaysia Department of mathematics University of SwabiSwabi 23561Pakistan Department of mathematics College of SciencesQassim UniversitySaudi Arabia Institute of Informatics and Computing in Energy(IICE) Universiti Tenaga NasionalKajangSelangorMalaysia Department of Political Science Bacha Khan University CharsaddaCharsadda 24420KPK Pakistan

In the last forty years,the rise of HIV has undoubtedly become a major concern in the field of public health,imposing significant economic burdens on affected ***,it becomes imperative to undertake comprehensive investigations into the mechanisms governing the dissemination of HIV within the human *** this work,we have devised a mathematical model that elucidates the intricate interplay between CD4^(+)T-cells and viruses of HIV,employing the principles of fractional *** production rate of CD4^(+)T-cells,like other immune cells depends on certain factors such as age,health status,and the presence of infections or ***,we incorporate a variable source term in the dynamics of HIV infection with a saturated incidence rate to enhance the precision of our *** introduce the fundamental concepts of fractional operators as a means of scrutinizing the proposed HIV *** facilitate a deeper understanding of our system,we present an iterative scheme that elucidates the trajectories of the solution pathways of the *** show the time series analysis of our model through numerical findings to conceptualize and understand the key factors of the *** addition to this,we present the phase portrait and the oscillatory behavior of the system with the variation of different input *** information can be utilized to predict the long-term behavior of the system,including whether it will converge to a steady state or exhibit periodic or chaotic oscillations.

关键词： HIV infection fractional-calculus dynamics of HIV iterative scheme dynamical behaviour mathematical model fractional derivatives

Partition-based Network Equivalent Method for Power System Subsynchronous Oscillation Analysis

在线全文

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 313-320页

作者： Chenxuan Wang Weimin Zheng Zhen Wang Yangqing Dan Ping Ju the Department of Electrical Engineering Zhejiang UniversityHangzhou 310027China the economic Research Institute of State Grid Zhejiang Electric Power Co. Ltd.Hangzhou 310016China the college of Energy and Electrical Engineering Hohai UniverstiyNanjing 211100China

Given large-scale modern power systems with pow er electronic converters,the numerical simulation with subsyn chronous oscillation(SSO)faces great challenges in engineering practice due to sharply enlarged modeling scale and high com putational *** reduce the modeling scale,network parti tion and equivalent becomes a vital technique in numerical sim *** several methods have been developed for net work equivalent,a generally accepted rule for network parti tion is still *** paper proposes that the system can be partitioned into three parts,i.e.,the internal,the middle,and the external subsystems,in which the internal subsystem consists of all power electronic components,the middle subsys tem includes those selected AC dynamic components with de tailed models,and the remaining components and buses consti tute the external *** external subsystem is further represented by an equivalent RLC network determined by the frequency dependent network equivalent(FDNE)*** the proposed method,the observability index and the electrical distance index are used to identify the interface between the middle and the external *** studies based on a modified Hydro-Quebec system are used to verify the effective ness of the proposed method.

关键词： Electrical distance network equivalent subsyn chronous oscillation observability index

Neuropeptide Y receptor Y8b(npy8br)regulates feeding and digestion in Japanese medaka(Oryzias latipes)larvae:evidence from gene knockout

在线全文

学校读者我要写书评

暂无评论

Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2024年第7期25卷 605-616页

作者： Xiaodan JIA Ke LU Xufang LIANG college of Fisheries Chinese Perch Research CenterHuazhong Agricultural UniversityWuhan 430070China Engineering Research Center of Green Development for Conventional Aquatic Biological Industry in the Yangtze River economic Belt Ministry of EducationWuhan 430070China

Neuropeptide Y receptor Y8(NPY8R)is a fish-specific receptor with two subtypes,NPY8AR and *** in expression levels during physiological processes or in vivo regulation after ventricular injection suggest that NPY8BR plays an important role in feeding regulation;this has been found in only a few fish,at *** order to better understand the physiological function of npy8br,especially in digestion,we used clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated protein 9(Cas9)technology to generate npy8br-/-japanese medaka(Oryzias latipes).We found that the deletion of npy8br in medaka larvae affected their feeding and digestion ability,ultimately affecting their ***,npy8br deficiency in medaka larvae resulted in decreased feed intake and decreased expression levels of orexigenic genes(npy and agrp).npy8br-/-medaka larvae fed for 10 d(10th day of feeding)still had incompletely digested brine shrimp(Artemia nauplii)in the digestive tract 8 h after feeding,the messenger RNA(mRNA)expression levels of digestion-related genes(amy,lpl,ctra,and ctrb)were significantly decreased,and the activity of amylase,trypsin,and lipase also significantly *** deletion of npy8br in medaka larvae inhibited the growth and significantly decreased the expression of growth-related genes(gh and igf1).Hematoxylin and eosin(H&E)sections of intestinal tissue showed that npy8br-/-medaka larvae had damaged intestine,thinned intestinal wall,and shortened intestinal *** far,this is the first npy8br gene knockout model established in fish and the first demonstration that npy8br plays an important role in digestion.

关键词： Neuropeptide Y receptor Y8b(npy8br) Japanese medaka(Oryzias latipes) Knockout Feeding Digestion

Rice planting acceleration of the activation and loss of soil iron in the red soil region of southern China

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Soil Ecology Letters 2024年第2期6卷 179-187页

作者： San’an Nie Jie Fan Ningxiang Ouyang Hao Sheng Yangzhu Zhang Xiong Yan Zhan Yu college of Resources Hunan Agricultural UniversityChangsha410125China School of economic Geography Hunan University of Finance and EconomicsChangsha410205China Zunyi Normal University Zunyi563006China

Rice planting decreased total iron but increased active *** activation varied greatly among different paddy soils but not in woodland *** soil iron was mainly affected by pH,SOC and particle *** decrease of soil Fe wa... 详细信息

关键词： paddy soil iron forms parent material rice planting Fe activation

MicroR-9c-5p and novel-mir50 co-target Akt to regulate Lasioderma serricorne reproduction

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Insect Science 2024年第1期31卷 106-118页

作者： Yi Yan Dong-Dong Qin Hong Yang Kang-Kang Xu Can Li Wen-Jia Yang Provincial Key Laboratory for Agricultural Pest Management of Mountainous Region Institute of EntomologyGuizhou UniversityGuiyangChina Guizhou Provincial Key Laboratory for Rare Animal and economic Insect of the Mountainous Region College of Biology and Environmental EngineeringGuiyang UniversityGuiyangChina

High fecundity is a common characteristic of insect pests which increases the difficulty of population ***/threonine kinase Akt is an indispensable component of the insulin signaling *** of LsAkt severely hinders reproduction in Lasioderma serricorne,a stored product insect ***,the post-transcriptional pathway of LsAkt in *** remains *** study identified 2 binding sites of miR-9c-5p and novel-mir50 in the coding sequences of *** expression profiles of 2 microRNAs(miRNAs)and LsAkt displayed an opposite pattern during the adult *** reporter assay showed that novel-mir50 and miR-9c-5p could downregulate the expression of *** of miR-9c-5p and novel-mir50 by injection of mimics inhibited the expression of LsAkt and reduced oviposition,decreased egg hatchability,and blocked ovarian *** also decreased the expression of genes involved in ovarian development(LsVg and LsVgR)and the nutritional signaling pathway(LsTOR,LsS6K,and Ls4EBP),and reduced the phosphorylation of ***,injection of miR-9c-5p and novel-mir50 inhibitors induced the expressions of LsAkt,LsVg,LsVgR,LsTOR,LsS6K,and Ls4EBP,enhanced Akt phosphorylation level,and accelerated ovarian *** of bovine insulin downregulated the expression of miR-9c-5p and novel-mir50 and upregulated the LsAkt *** also rescued the reproductive development defects associated with miR-9c-5p/novel-mir50 overexpression,forming a positive regulatory loop of insulin *** results indicate that miR-9c-5p/novel-mir50 regulates the female reproduction of *** by targeting Akt in response to insulin *** data also demonstrate the effects of the insulin/miRNA/Akt regulatory axis in insect reproduction.

关键词： Akt insulin Lasioderma serricorne microRNA reproduction

Composition optimization and performance prediction for ultra-stable water-based aerosol based on thermodynamic entropy theory

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Defence Technology（防务技术） 2024年第3期33卷 437-446页

作者： Tingting Kang Canjun Yan Xinying Zhao Jingru Zhao Zixin Liu Chenggong Ju Xinyue Zhang Yun Zhang Yan Wu college of Chemical Engineering and Materials Science Tianjin University of Science and TechnologyNo.29 13th AvenueEconomic and Technologic Development ZoneTianjin 300457China Tianjin Key Laboratory of Brine Chemical Engineering and Resource Eco-utilization Tianjin University of Science and TechnologyTianjin 300457China college of Meteorology and Oceanography National University of Defense TechnologyChangsha 410073China

Water-based aerosol is widely used as an effective strategy in electro-optical countermeasure on the battlefield used to the preponderance of high efficiency,low cost and ***,the stability of the water-based aerosol is always unsatisfactory due to the rapid evaporation and sedimentation of the aerosol *** efforts have been devoted to improve the stability of water-based aerosol by using additives with different composition and ***,the lack of the criterion and principle for screening the effective additives results in excessive experimental time consumption and *** the stabilization time of the aerosol is still only 30 min,which could not meet the requirements of the perdurable ***,to improve the stability of water-based aerosol and optimize the complex formulation efficiently,a theoretical calculation method based on thermodynamic entropy theory is *** the factors that influence the shielding effect,including polyol,stabilizer,propellant,water and cosolvent,are considered within *** ultra-stable water-based aerosol with long duration over 120 min is obtained with the optimal fogging agent composition,providing enough time for fighting the electro-optic *** design guideline for choosing the additives with high phase transition temperature and low phase transition enthalpy is also proposed,which greatly improves the total entropy change and reduce the absolute entropy change of the aerosol cooling process,and gives rise to an enhanced stability of the water-based *** theoretical calculation methodology contributes to an abstemious time and space for sieving the water-based aerosol with desirable performance and stability,and provides the powerful guarantee to the homeland security.

关键词： Ultra-stable Water-based aerosol Thermodynamic entropy Composition optimization Performance prediction

Explainable artificial intelligence models for mineral prospectivity mapping

在线全文

学校读者我要写书评

暂无评论

Science China Earth Sciences 2024年第9期67卷 2864-2875页

作者： Renguang ZUO Qiuming CHENG Ying XU Fanfan YANG Yihui XIONG Ziye WANG Oliver P.KREUZER State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences School of Earth Sciences and Engineering Sun Yat-sen University Corporate Geoscience Group (CGSG) economic Geology Research Centre (EGRU) College of Science and EngineeringJames Cook University

Mineral prospectivity mapping(MPM) is designed to reduce the exploration search space by combining and analyzing geological prospecting big data. Such geological big data are too large and complex for humans to effectively handle and interpret. Artificial intelligence(AI) algorithms, which are powerful tools for mining nonlinear mineralization patterns in big data obtained from mineral exploration, have demonstrated excellent performance in MPM. However, AI-driven MPM faces several challenges, including difficult interpretability, poor generalizability, and physical inconsistencies. In this study, based on previous studies, we devised a novel workflow that aims to constructing more transparent and explainable artificial intelligence(XAI) models for MPM by embedding domain knowledge throughout the AI-driven MPM, from input data to model design and model output. This newly proposed approach provides strong geological and conceptual leads that guide the entire AI-driven MPM model training process, thereby improving model interpretability and performance. Overall, the development of XAI models for MPM is capable of embedding prior and expert knowledge throughout the modeling process, presenting a valuable and promising area for future research designed to improve MPM.

关键词： Artificial intelligence Mineral prospectivity mapping Geological prospecting big data Domain knowledge Interpretability

同方期刊数据库