检索结果-南通市图书馆

Optimization Method for Electrical Water Heaters Considering Shifting Potentials of Electricity Consumption and Water-use Activities

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Modern Power Systems and Clean Energy 2024年第4期12卷 1250-1259页

作者： Yuqing Bao Zhonghui Zuo Xuehua Wu school of Electrical and Automation Engineering Nanjing Normal UniversityNanjing 210046China school of Electrical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210023China

Electrical water heaters(EWHs)are important can-didates to provide demand-response *** traditional optimization method for EWHs focuses on the optimization of the electricity consumption,without considering the shifting potential of the wateruse *** paper proposes an optimization method for EWHs considering the shifting potentials of both the electricity consumption and wateruse ***-sidering that the wateruse activities could be monolithically shifted,the shifting model of the water-use activities was *** addition to the thermodynamic model of the EWH,the optimal scheduling model of the EWH was developed and solved using mixed-integer linear *** studies were performed on a single EWH and aggregate EWHs,demon-strating that the proposed method can shift the water-use activities and therefore increase the load-shifting potential of the EWHs.

关键词： Electrical water heater(EWH) demand response load-shifting water-use activity

Classification of aviation incident causes using LGBM with improved cross-validation

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Engineering and Electronics 2024年第2期35卷 396-405页

作者： NI Xiaomei WANG Huawei CHEN Lingzi LIN Ruiguan school of Civil Aviation Nanjing University of Aeronautics and AstronauticsNanjing 211106China school of Aeronautical Engineering Nanjing Vocational University of Industry TechnologyNanjing 210023China

Aviation accidents are currently one of the leading causes of significant injuries and deaths worldwide. This entices researchers to investigate aircraft safety using data analysis approaches based on an advanced machine learning *** assess aviation safety and identify the causes of incidents, a classification model with light gradient boosting machine (LGBM)based on the aviation safety reporting system (ASRS) has been developed. It is improved by k-fold cross-validation with hybrid sampling model (HSCV), which may boost classification performance and maintain data balance. The results show that employing the LGBM-HSCV model can significantly improve accuracy while alleviating data imbalance. Vertical comparison with other cross-validation (CV) methods and lateral comparison with different fold times comprise the comparative approach. Aside from the comparison, two further CV approaches based on the improved method in this study are discussed:one with a different sampling and folding order, and the other with more CV. According to the assessment indices with different methods, the LGBMHSCV model proposed here is effective at detecting incident causes. The improved model for imbalanced data categorization proposed may serve as a point of reference for similar data processing, and the model’s accurate identification of civil aviation incident causes can assist to improve civil aviation safety.

关键词： aviation safety imbalance data light gradient boosting machine(LGBM) cross-validation(CV)

Electromagnetic properties of the Pc(4312) pentaquark state

在线全文

学校读者我要写书评

暂无评论

Chinese Physics C 2021年第2期45卷 341-350页

作者： UlaşÖzdem Health Services vocational school of Higher Education Istanbul Aydin UniversitySefakoy-Kucukcekmece34295 IstanbulTurkey

Using the light-cone QCD sum rules,we evaluate the magnetic moment of the P_c(4312) pentaquark state by considering both the \bar D\Sigma_c molecular and diquark-diquark-antiquark state,with quantum numbers J^P=2/1^(-1).In the calculations,we use the diquark-diquark-antiquark and molecular form of the interpolating currents for the P_(c4312) pentaquark and the distribution amplitudes of the *** numerical results for the magnetic moment obtained using the two different pictures are quite different from each other,which can be used to pin down the underlying structure of P_(c4312) .Any experimental measurement of the magnetic moment in the near future will provide an understanding of the internal structure of this pentaquark state.

关键词： pentaquarks magnetic moment molecular picture diquark-diquark-antiquark picture

Three-to-one internal resonance in multiple stepped beam systems

在线全文

学校读者我要写书评

暂无评论

Applied Mathematics and Mechanics(English Edition) 2009年第9期30卷 1131-1142页

作者： A. Tekin E. zkaya S. M. Bagdatlh Technical vocational school of Higher Education Celal Bayar University Department of Mechanical Engineering Celal Bayar University

In this study, the vibrations of multiple stepped beams with cubic nonlinearities are considered. A three-to-one internal resonance case is investigated for the system. A general approximate solution to the problem is found using the method of multiple scales （a perturbation technique）. The modulation equations of the amplitudes and the phases are derived for two modes. These equations are utilized to determine steady state solutions and their stabilities. It is assumed that the external forcing frequency is close to the lower frequency. For the numeric part of the study, the three-to-one ratio in natural frequencies is investigated. These values are observed to be between the first and second natural frequencies in the cases of the clamped-clamped and clamped-pinned supports, and between the second and third natural frequencies in the case of the pinned-pinned support. Finally, a numeric algorithm is used to solve the three-to-one internal resonance. The first mode is externally excited for the clamped-clamped and clamped-pinned supports, and the second mode is externally excited for the pinned-pinned support. Then, the amplitudes of the first and second modes are investigated when the first mode is externally excited. The amplitudes of the second and third modes are investigated when the second mode is externally excited. The force-response, damping-response, and .frequency- response curves are plotted for the internal resonance modes of vibrations. The stability analysis is carried out for these plots.

关键词： stepped beam three-to-one internal resonance stability analysis nonlinear vibration perturbation method

Robust H_∞ Filter Design for Time-delay Systems with Saturation

在线全文

学校读者我要写书评

暂无评论

International Journal of Automation and computing 2013年第4期10卷 368-374页

作者： Xiao-Fang Hong Yu-Zhen Wang Hai-Tao Li school of Control Science and Engineering Shandong University Department of Electrical and Automation Shandong Labor Vocational and Technical College

This paper investigates the H∞ filtering problem for a class of linear continuous-time systems with both time delay and saturation. Such systems have time delay in their state equations and saturation in their output equations, and their process and measurement noises have unknown statistical characteristics and bounded energies. Based on the Lyapunov-Krasovskii stability theorem and the linear matrix inequalities （LMIs） technique, a generalized dynamic filter architecture is proposed, and a filter design method is developed. The linear H∞ filter designed by the method can guarantee the H∞ performance. The parameters of the designed filter can be obtained by solving a kind of LMI. An illustrative example shows that the design method proposed in this paper is very effective.

关键词： H∞ filter saturation time delay nonlinear system linear matrix inequality.

Non-equidistance DGM(1,1) Model Based on the Concave Sequence and Its Application to Predict the China’s Per Capita Natural Gas Consumption

在线全文

学校读者我要写书评

暂无评论

Journal of Systems Science and Information 2018年第4期9卷 376-384页

作者： Xinhai KONG Yong ZHAO Jiajia CHEN school of Intelligent Manufacturing and Energy Engineering Guang’an Vocational and Technical College school of Education Guang’an Vocational and Technical College

Although the grey forecasting model has been successfully adopted in various fields and demonstrated promising results, the literatures show its performance could be further improved, such as for the DGM(1,1) model, based on a concave sequence, the modeling error will be larger. In this paper,firstly the definition of sequence convexity is given out, and it is proved that the output sequence of DGM(1,1) model is a convex sequence. Next, the residual change law of DGM(1,1) model based on the concave sequence is discussed, and the non-equidistance DGM(1,1) model is proposed. Finally, by introducing the symmetry transformation, a concave sequence is transformed into a convex sequence, called the symmetric sequence of the concave sequence, and then construct the non-equidistance DGM(1,1)model based on the convex sequence. The example results show that the novel method is more accurate than the direct modeling for a concave sequence.

关键词： DGM(1,1) Model concave sequence initialization symmetry transformation non-equidistance DGM(1,1) model

An investigation of gamma ray mass attenuation from 80.1 to 834.86 keV for fabric coating pastes used in textile sector

在线全文

学校读者我要写书评

暂无评论

Nuclear Science and Techniques 2020年第6期31卷 52-59页

作者： Alev Erenler Tuncay Bayram Yusuf Demirel Erhan Cengiz Rıza Bayrak Gerze vocational school Sinop UniversitySinopTurkey Department of Physics Karadeniz Technical University61080 TrabzonTurkey Department of Engineering Fundamental Sciences Alanya Alaaddin Keykubat UniversityAntalyaTurkey vocational school of Health Services Sinop UniversitySinopTurkey

In the present study,we investigate several textile coating pastes used in the market based on their radiation protection capability for gamma *** gamma ray mass absorption coefficients of some coating pastes doped with antimony,boron and silver elements have been *** has been determined that the gamma ray mass attenuation coefficient decreases rapidly as the energy of the gamma rays *** was determined that the doping of the main printing paste with silver and antimony considerably increased the gamma ray absorption capability of main ***,the doping of the paste with boron reduces the mass absorption of gamma *** particular,the gamma ray mass absorption power of the main paste doped with silver and antimony was determined to be useful in the gamma energy range from 80 to *** indicates that the newly doped textile material may be considered for radiation protection in the case of low-energy gamma rays.

关键词： Gamma ray absorption Radiation protection Printing pastes antimony silver

在线全文

学校读者我要写书评

暂无评论

Layered D2D NOMA

China Communications 2021年第1期18卷 33-42页

作者： Jinjuan Ju Jinyuan Gu Guan Zhang school of Information Science and Technology Nantong UniversityNantong 226019China school of Electronic and Information Engineering Nantong Vocational UniversityNantong 226007China

This paper investigates a layered power allocation(PA)non-orthogonal multiple access(NOMA)scheme for device-to-device(D2D)relaying networks,where the strategy of partial data transmission at relay nodes are adopted to improve the efficiency of *** addition,to satisfy different quality-of-service(QoS)requirements from multiple users,layered and grouped manners are ***,the closed-form expressions in terms of the sum-rate(SR)and outage probability of the proposed scheme are derived for independent Rayleigh fading channels,which demonstrates our theoretical *** analytical and simulation results are provided to show the superiority of our proposed scheme compared with existing works.

关键词： non-orthogonal multiple access deviceto-device sum-rate outage probability

Some logarithmic Minkowski inequalities for nonsymmetric convex bodies

在线全文

学校读者我要写书评

暂无评论

Science China Mathematics 2017年第10期60卷 1857-1872页

作者： WANG XingXing XU WenXue ZHOU JiaZu school of Mathematics and Statistics Southwest UniversityChongqing 400715China Southwest Guizhou vocational College of Technology for Nationalities Kaili 556000China

We prove some analogs inequalities of the logarithmic Minkowski inequality for general nonsymmetric convex bodies. As applications of one of those inequalities, the p-affine isoperimetric inequality and some other ine... 详细信息

关键词： log-Minkowski inequality Minkowski inequality p-affine isoperimetric inequality dual log-Minkowski inequality