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Improved unequal interval grey model and its applications

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Journal of Systems Engineering and Electronics 2011年第3期22卷 445-451页

作者： yuhong wang Yaoguo Dang Xujin Pu School of Business Jiangnan UniversityWuxi 214122P.R.China College of Economics and Management Nanjing University of Aeronautics and AstronauticsNanjing 210016P.R.China

A new method to improve prediction precision of GM（1,1） model with unequal time interval is *** grey derivative is multiplied by a parameter to guarantee the time response function satisfying approximately exponential function *** simplify the process of parametric estimation,an approximate value is taken for the multiplied *** the estimators of coefficient of development and grey action quantity can be *** the same time,the principle of the new information priority is also *** take the last item of the first-order accumulated generation operator（1-AGO） on raw data sequence as the initial condition in the time response *** the new information can be taken full advantage of through the improved initial *** properties of this new model are also *** presented method is actually a combination of improvement of grey derivative and improvement of the initial *** results of an example indicate that the proposed method can improve prediction precision prominently.

关键词： grey derivative initial condition GM(1 1) model unequal interval.

The Viscosity-reducing Mechanism of Organic Wax Additive on CRMA

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Journal of Wuhan University of Technology(Materials Science) 2013年第4期28卷 726-732页

作者：于新 wang yuhong WEI Tangzhong College of Civil and Transportation Engineering Hohai University Department of Civil and Structural Engineering The Hong Kong Polytechnic University

CRMA was prepared by mixing PG 64-22 asphalt with crumb rubber powder of 40 mesh size and 18% by weight of the asphalt. Sasobit, a typical organic wax additive, was selected and added into CRMA. A series of tests, namely, brookfield viscosity, environmental scanning electron microscope（ESEM）, component test, differential scanning calorimeter（DSC）, fourier transform infrared spectroscopy （FTIR） and nuclear magnetic resonance （NMR） were conducted on CRMA with and without organic wax additive, and microcosmic appearance, component content and molecular structure of various asphalt binders were obtained. The test results indicate that the addition of Sasobit~ into CRMA can effectively change the contents of components： the content of asphaltenes increases relatively, while saturates decreases. In addition, the interaction between various components of CRMA is weakened, and the state of equilibrium between the dispersant and dispersed phase is changed at the same time. That is why the viscosity decreases after the organic wax additive is added into CRMA.

关键词： crumb rubber modified asphalt (CRMA) viscosity-reducing organic wax additives mechanism

Improvement and application of GM(1,1) model based on multivariable dynamic optimization

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Journal of Systems Engineering and Electronics 2020年第3期31卷 593-601页

作者： wang yuhong LU Jie School of Business Jiangnan UniversityWuxi 214122China

For the classical GM(1,1)model,the prediction accuracy is not high,and the optimization of the initial and background values is *** this paper,the Lagrange mean value theorem is used to construct the background value as a variable related to *** the same time,the initial value is set as a variable,and the corresponding optimal parameter and the time response formula are determined according to the minimum value of mean relative error(MRE).Combined with the domestic natural gas annual consumption data,the classical model and the improved GM(1,1)model are applied to the calculation and error comparison *** proves that the improved model is better than any other models.

关键词： grey prediction GM(1,1)model background value grey system theory

High resolution oxygen isotope and grayscale records of a medieval fossil giant clam(Tridacna gigas) in the South China Sea: physiological and paleoclimatic implications

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Acta Oceanologica Sinica 2014年第8期33卷 18-25页

作者： YAN Hong wang yuhong SUN Liguang State Key Laboratory of Loess and Quaternary Geology Institute of Earth EnvironmentChinese Academy of Sciences Institute of Polar Environment School of Earth and Space SciencesUniversity of Science and Technology of China Advanced Management Research Center Ningbo University

Mollusks are well known for their detailed recording of paleoenvironmental and paleoclimatic changes in their carbonate shells. In this study, we constructed 18-year blue color intensity and oxygen isotope profiles of a14C dated （AD 990±40） fossil giant clam,Tridacna gigas, from Shidao Island, South China Sea. Theδ18O profile of theT. gigas specimen displayed regular annual cycles and was probably controlled by seasonal variations of the climatic parameters. The blue color intensity profile showed good agreement with theδ18O series, and both had 18 clear annual cycles in accordance with the 18 visually identified annual growth bands. The annual shell growth rate determined from the blue color intensity and oxygen isotope profiles indicated that the annual shell increment of theTridacna specimen was stable after the onset of sexual ma-turity. Spectral analysis of theδ18O and blue color intensity time series suggested that the El Ni？o-Southern Oscillation （ENSO） period observed in the instrumental temperature and precipitation records of the South China Sea during the past 50 years also existed in medieval times. Our results showed that fossil giant clams could provide a good archive of historical intra-seasonal to decadal climate variations.

关键词： Tridacna gigas oxygen isotope blue color intensity Medieval Warm Period sea surface temperature El Ni?o–Southern Oscillation

H_∞ Control for Nonlinear Stochastic Markov Systems with Time-Delay and Multiplicative Noise

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Journal of Systems Science & Complexity 2017年第6期30卷 1293-1315页

作者： wang yuhong PAN Zhiteng LI Yan ZHANG Weihai College of Information and Control Engineering China University of Petroleum (East China) College of Electrical Engineering and Automation Shandong University of Science and Technology

This paper is concerned with the H_∞ control problem for a class of nonlinear stochastic Markov jump systems with time-delay and system state-, control input-and external disturbancedependent noise. Firstly, by solving a set of Hamilton-Jacobi inequalities(HJIs), the exponential mean square H_∞ controller design of delayed nonlinear stochastic Markov systems is presented. Secondly,by using fuzzy T-S model approach, the H_∞ controller can be designed via solving a set of linear matrix inequalities(LMIs) instead of HJIs. Finally, two numerical examples are provided to show the effectiveness of the proposed design methods.

关键词： H∞ control Markov jump systems nonlinear stochastic systems time-delay (x,u,v)-dependent noise

Ecosystem evolution of seal colony and the influencing factors in the 20th century on Fildes Peninsula,West Antarctica

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Journal of Environmental Sciences 2011年第9期23卷 1431-1436页

作者： Jing Huang Liguang Sun Xinming wang yuhong wang Tao Huang Institute of Polar Environment University of Science & Technology of China Hefei 230026 China Guangzhou Institute of Geochemistry Chinese Academy of Science Guangzhou 510640 China Advanced Management Research Center Ningbo University Ningbo 315211 China

As the topmost predator in Antarctica,the seal is a unique indicator of Antarctic environment and climate *** this study,we collected a sediment core from the Fildes Peninsula of West Antarctica,and used cholesterol,cholestanol,epicoprostanol,coprostanol,and seal hair numbers as the proxy indicators of seal population size and phytol as of general vegetation,and we reconstructed the 20th century history of variation of the seal population and vegetation abundance on this *** sealing industry in the early 20th century caused the dramatic decline of seal population,and the ban of seal hunting since the 1960s led to its recovery of seal *** seal population during the past century was primarily controlled by human activities and krill *** reconstructed relation between seal population and vegetation abundance may offer new insights into Antarctic environment and ecology.

关键词： fecal sediment molecular marker human culture seal ecosystem climate

Millennial mercury records derived from ornithogenic sediment on Dongdao Island,South China Sea

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Journal of Environmental Sciences 2011年第9期23卷 1415-1423页

作者： Hong Yan yuhong wang Wenhan Cheng Liguang Sun Institute of Polar Environment University of Science and Technology of China Hefei 230026 China National Institutes of Health Bethesda MD 20892 USA

Two ornithogenic sediment cores,which have a time span of 1000 years and are influenced by red-footed booby （Sula sula）,were collected from Dongdao Islands,South China *** determined mercury concentrations of the two cores show similar and substantial fluctuations during the past millennium,and the fluctuations are most likely caused by the changes in mercury level of the ocean environment and in anthropogenic Hg *** the past 500 years,the mercury concentration in the red-footed booby excrement has a striking association with global anthropogenic mercury *** mercury concentration increased rapidly after AD 1600 in corresponding to beginning of the unparalleled gold and silver mining in South Central America that left a large volume of anthropogenic mercury *** the Industrial Revolution,the mercury level has increased at a fast pace,very likely caused by modern coal combustion,chlor-alkali and oil refining *** comparison of mercury profiles from different places on earth suggested that anthropogenic mercury pollution after the Industrial Revolution is more severe in Northern Hemisphere than in Antarctica.

关键词： South China Sea red-footed booby ornithogenic sediment mercury anthropogenic source

Real-time intersection vehicle turning movement counts from live UAV video stream using multiple object tracking

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Journal of Intelligent and Connected Vehicles 2023年第3期6卷 149-160页

作者： Yuhao wang Ivan wang-Hei Ho yuhong wang Department of Electrical and Electronic Engineering The Hong Kong Polytechnic UniversityHong Kong SARChina Otto Poon Charitable Foundation Smart Cities Research Institute The Hong Kong Polytechnic UniversityHong Kong SARChina Department of Civil and Environmental Engineering The Hong Kong Polytechnic UniversityHong Kong SARChina

The intelligent transportation system(ITS)is committed to ensuring safe and effective next-generation traffic throughout a ***,such efficient operation on urban traffic networks needs the support of big traffic data,especially Turning Movement Counts(TMC)at ***,TMC data are more challenging to collect due to labor cost and accuracy *** this paper,we leverage the capabilities of Unmanned Aerial Vehicles(UAV)to collect real-time TMC data in a cost-efficient *** proposed a real-time TMC data collection framework based on a live video *** vehicle tracking capability is boosted by multiple object tracking based on tracking by *** addition,a challenging case study was conducted,and our results demonstrate the feasibility and robustness of the proposed TMC data collection ***,with a GTX 1650 graphics card,about 10 FPS can be achieved in real-time for the TMC data *** overall accuracy is 91.93%,and the best case is over 98%*** the context of miscounting,the major reason is due to ID switching caused by background *** proposed framework is expected to provide real-time data for traffic capacity analysis and advanced traffic simulation such as digital twins.

关键词： turning movement counts unmanned aerial vehicles multi objects tracking real-time

Identification and prioritization of key health hazards to workers in roadway construction

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Transportation Safety and Environment 2022年第2期4卷 76-87页

作者： Shicong Mo yuhong wang Feng Xiong Department of Civil and Environment Engineering The Hong Kong Polytechnic UniversityHung Hom 999077Hong Kong SARChina College of Architecture and Environment Sichuan UniversityChengdu 610065China.

Although various rating systems have been developed to promote sustainable development in roadway construction,sustainability evaluation from the perspective of safeguarding workers’health is currently *** approaches were used in the study to identify and prioritize key health hazards to workers in roadway construction,including bibliometric analysis,questionnaire survey and analytic hierarchy process(AHP).Bibliometric analysis indicates that submicron particles and polycyclic aromatic compounds are the primary concerns of researchers,and ergonomics also attracts some attention.A questionnaire survey was conducted among construction workers in *** results suggest that the most frequently encountered occupational disorders by roadway construction workers are musculoskeletal disorders,heat stroke,respiratory health issues and hearing loss,and the most commonly encountered hazards are noise,dust,asphalt fumes,heat stress and some adverse working *** on associations between the health hazards and disorders were *** there are some discrepancies between the AHP scores provided by two groups of professionals in China,the commonly agreed top occupational hazards include dust,asphalt fumes,noise,high-/low-temperature stresses and chronic *** findings may be incorporated into rating systems for roadway construction to encourage the industry to adopt better practices for the well-being of workers.

关键词： sustainable construction occupational health roadway workers hazards and exposures analytic hierarchy process