Associating Semantic Sensor Web with Domain Ontology : The Way to Obtain Meaningful Sensor Data

Chaoqun Ji,Jin Liu,Xiaofeng Wang 보안공학연구지원센터 2014 International Journal of u- and e- Service, Scienc Vol.7 No.5

To realize the sharing and reuse of sensor data and improve interoperability, semantic sensor web(SSW)is proposed to add semantics information to existing sensor networksby utilizing domain, spatial and temporal anthologies and other related semantic technology.However these is seldom research on how to fully utilize the sensor data through a semantic way such as domain ontology based inference. This paperpresents stateofthe art of SSWin various aspects,and proposesthe method to associate data from semantic sensor web with domain ontology to realize the communication between different domain ontologies and SSW. In addition, this paperalso proposes a new calculation method of semantic similarity amongdifferent entities in different ontology. Experiments show that this method can effectively find the similar entitiesandrealize the knowledge sharing and ontologies reuse.

Small-signal Impedance Model of an Inductive Power Transfer System Using LCC-LCC Compensation

Chaoqun Qi,Guangce Zheng,Xinlin Wang,Xiaoxuan Ji,Minfan Fu 전력전자학회 2023 ICPE(ISPE)논문집 Vol.2023 No.-

Unregulated inductive power transfer systems are widely adopted for wireless charging scenarios. Such a system is usually cascaded with a dc/dc converter for input or output regulation. The overall system stability needs an in-depth study of the terminal impedance from the small signal perspective. This paper focuses on the impedance model of an LCC-LCC compensated system. An equivalent circuit model is built and used to explicitly derive the input and output impedance. The experiment results show that the model is simple and accurate up to 1/5 of the switching frequency.

Encapsulation of TiO2 particles with polystyrene and polymethyl acrylic acid and the pigmentary performances

Chaoqun Ge,Aili Wang,Hengbo Yin 한국공업화학회 2012 Journal of Industrial and Engineering Chemistry Vol.18 No.4

TiO2 particles were directly encapsulated with polystyrene and polymethyl acrylic acid by a surfactantfree polymerization method. TiO2 particles were uniformly encapsulated with polystyrene by Van der Waals force and effectively encapsulated with polymethyl acrylic acid by chemical bonding. Encapsulation of TiO2 particles with polystyrene and polymethyl acrylic acid significantly enhanced the organic dispersibility and dispersion stability of TiO2 particles in toluene because the surface property of TiO2 particles was changed from hydrophilicity to organophilicity after polymer encapsulation. The brightness and whiteness of the polymer-encapsulated TiO2 particles were similar to that of the naked TiO2.

Research on 3D Laser Scanning Monitoring Method for Mining Subsidence Based on the Auxiliary for Probability Integral Method

Lei Wang,Shangjun Zhu,Chuang Jiang,Jingyu Li,Kegui Jiang,Chaoqun Teng,Tao Wei,Qing-biao Guo 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.11

When 3D laser scanning technology is used to monitor the surface deformation of mining subsidence in mining area, the surface of the working face is covered with a large number of vegetation, and the surface water accumulates above the working face, which makes the point cloud data obtained by the 3D laser scanning difficult to denoise, or even missing. At this time, the conventional 3D laser scanning technology can not obtain the surface deformation field of mining subsidence. Aiming at the above problems, the 3D laser scanning monitoring method for mining subsidence based on the auxiliary for PIM proposed (3DLS-PIM). Firstly, this paper introduces the PIM prediction model. Secondly, the mining subsidence observation equation based on 3DLS-PIM is constructed, and then the prediction parameters of PIM are solved based on quantum particle swarm optimization (QPSO). Finally, according to the PIM and its parameters, the mining subsidence surface deformation basin is predicted and obtain the surface deformation field of mining subsidence. Robust experiments show that QPSO has a certain ability to resist random errors and gross errors. The results of engineering application show that the mining area 3D deformation monitoring method proposed in this paper has certain engineering application value.

A Fast and Generalized Space-Vector Modulation Scheme for Cascaded H-bridge Multilevel Converters Under Faulty Conditions

Wanxing Wang,Yan Zhang,Chaomin Xiao,Yang Li,Chaoqun Ma,Jinjun Liu 전력전자학회 2023 ICPE(ISPE)논문집 Vol.2023 No.-

Space vector modulation (SVM) is widely used for voltage source inverters, but it is too complicated when extended to the cascaded H-bridge multilevel converter (CHMC) under faulty conditions. In this article, a fast and universal SVM strategy is proposed to realize postfault operation for CHMC. Different fault types can be reflected by the reduction of phase voltage so the proposed scheme first calculates all the available redundant switching states based on available output voltage in three phases. Final-selected switching state is within the selectable range based on the reduced common-mode voltage principle. To generate the switching sequence, discontinuous pulse-width modulation (DPWM) is used, which improves efficiency of the system. The proposed SVM scheme is independent of the number of levels and can be applied in different fault conditions. The performance and effectiveness of the proposed strategy are verified by simulation results.

D-InSAR Monitoring Method of Mining Subsidence Based on Boltzmann and Its Application in Building Mining Damage Assessment

Lei Wang,Chaoqun Teng,Kegui Jiang,Chuang Jiang,Shangjun Zhu 대한토목학회 2022 KSCE JOURNAL OF CIVIL ENGINEERING Vol.26 No.1

Monitoring and predicting mining area subsidence caused by coal mining help effectively control geological disasters. Information regarding small surface deformations can be obtained using a differential interferometric synthetic aperture radar (D-InSAR), which exhibits high monitoring accuracy and can cover large areas; thus, D-InSAR are being applied for mining area settlement monitoring. However, mining areas are prone to large gradient deformations in short durations; obtaining information regarding such deformations is outside the scope of D-InSAR monitoring. To adapt to the characteristics of D-InSAR monitoring, this study selected a Boltzmann function model with a slow boundary convergence rate to address the problem of probabilistic integration methods exhibiting a high boundary convergence rate. The three-dimensional surface deformation of the mining area can be accurately obtained. According to the projection relationship between D-InSAR line of sight (LOS) directional deformation, subsidence, and horizontal movement, a D-InSAR monitoring equation for mining subsidence assisted by Boltzmann is derived. This equation is combined with the shuffled frog leaping algorithm (SFLA) to obtain the parameters to be estimated from the equation. The D-InSAR LOS deformation information of the 13121 working face in the Huainan mining area was obtained from July 14 to October 30, 2019. The proposed method was then used to obtain the predicted parameters of the working face under insufficient mining. The predicted parameters of mining subsidence were calculated to obtain the predicted parameters when it was fully mined. Then, the revised parameters were used to predict the subsidence and horizontal movement of the mining area and compared with the actual leveling observations. The results show that the mean square error of predicted subsidence is 97.1 mm, which is about 3.09% of the maximum subsidence value; the mean square error of predicted horizontal movement is 46.1 mm, which is about 4.1% of the maximum horizontal movement value. The predicted results of the aforementioned method were used to analyze the damage to the buildings above the working face and determine the damage level of the buildings to provide a reference for the demolition and maintenance of the Zhaimiao village.

LES investigation into the generation of momentum deficits in the supersonic wake of a micro-ramp

Xiao Wang,Yonghua Yan,Zhengzhong Sun,Chaoqun Liu 대한기계학회 2014 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.28 No.4

Implicitly implemented large eddy simulation (LES) with a fifth-order WENO scheme was conducted in this study. Based on Navier- Stokes equations, this LES was carried out to explore the origin of momentum deficit caused by a supersonic micro-ramp at flow conditions of Ma = 2.5 and Reθ = 5760. The numerical results were validated through qualitative and quantitative comparisons with existing experimental data. After describing the aerodynamic properties of the supersonic wake, such as the deficit and the streamwise vortices, the momentum deficit was later detected to originate from the lower portion of the upstream boundary layer, while the high momentum fluid originated from close to the wall at the upper portion. Position alternation trigged by the micro-ramp was finally proposed as a revised mechanism.

Insights into interfacial stability of Li6PS5Cl solid electrolytes with buffer layers

Bingbing Chen,Chaoqun Xu,Han Wang,Jianqiu Zhou 한국물리학회 2019 Current Applied Physics Vol.19 No.2

The large interfacial resistance seriously restricts the development of all-solid-state lithium batteries (ASSLBs). In our work, first-principles calculations are employed to investigate the interfacial properties on lithium (Li) metal anode/Li6PS5Cl solid electrolyte (LPSCl) interface system as well as buffer layers (Li2S) effects. The stable interface structures, Li/LPSCl, L2S/LPSCl and Li/L2S, are established at atomic level. We find that PS4 tetrahedral structure has been seriously destroyed in Li/LPSCl interface, whereas the presence of Li2S buffer layers may smooth the interface without PS4 tetrahedral damage occurred. In addition, the electronic structure of interface indicates that solid electrolyte interphases are not easy to form on LPSCl surfaces considering buffer layers effects, which may improve the stability of anode/solid electrode interface. Moreover, the calculated energies of exchange ions between Li metal and solid electrolyte with buffer layers suggest that the Li2S interposition can suppress the atoms diffusion in LPSCl layers, and provide a smooth interface structure, which may promote the stability of Li/LPSCl interface. This work on the atomic scale will offer a useful perspective for designing high performance of solid electrolytes to enhance good cyclability in ASSLBs.

Galloping of steepled main cables in long-span suspension bridges during construction

Yonghui An,Chaoqun Wang,Shengli Li,Dongwei Wang 한국풍공학회 2016 Wind and Structures, An International Journal (WAS Vol.23 No.6

Large amplitude oscillation of steepled main cables usually presents during construction of a long-span bridge. To study this phenomenon, six typical main cables with different cross sections during construction are investigated. Two main foci have been conducted. Firstly, aerodynamic coefficients of a main cable are obtained and compared through simulation and wind tunnel test: (1) to ensure the simulation accuracy, influences of the numerical model's grid size, and the jaggy edges of main cable's aerodynamic coefficients are investigated; (2) aerodynamic coefficients of main cables at different wind attack angles are obtained based on the wind tunnel test in which the experimental model is made by rigid plastic using the 3D Printing Technology; (3) then numerical results are compared with wind tunnel test results, and they are in good agreement. Secondly, aerodynamic coefficients of the six main cables at different wind attack angles are obtained through numerical simulation. Then Den Hartog criterion is used to analyze the transverse galloping of main cables during construction. Results show all the six main cables may undergo galloping, which may be an important reason for the large amplitude oscillation of steepled main cables during construction. The flow structures around the main cables indicate that the characteristic of the airflow trajectory over a steepled main cable may play an important role in the galloping generation. Engineers should take some effective measures to control this harmful phenomenon due to the big possibility of the onset of galloping during the construction period.

Galloping of steepled main cables in long-span suspension bridges during construction

An, Yonghui,Wang, Chaoqun,Li, Shengli,Wang, Dongwei Techno-Press 2016 Wind and Structures, An International Journal (WAS Vol.23 No.6

Large amplitude oscillation of steepled main cables usually presents during construction of a long-span bridge. To study this phenomenon, six typical main cables with different cross sections during construction are investigated. Two main foci have been conducted. Firstly, aerodynamic coefficients of a main cable are obtained and compared through simulation and wind tunnel test: (1) to ensure the simulation accuracy, influences of the numerical model's grid size, and the jaggy edges of main cable's cross section on main cable's aerodynamic coefficients are investigated; (2) aerodynamic coefficients of main cables at different wind attack angles are obtained based on the wind tunnel test in which the experimental model is made by rigid plastic using the 3D Printing Technology; (3) then numerical results are compared with wind tunnel test results, and they are in good agreement. Secondly, aerodynamic coefficients of the six main cables at different wind attack angles are obtained through numerical simulation. Then Den Hartog criterion is used to analyze the transverse galloping of main cables during construction. Results show all the six main cables may undergo galloping, which may be an important reason for the large amplitude oscillation of steepled main cables during construction. The flow structures around the main cables indicate that the characteristic of the airflow trajectory over a steepled main cable may play an important role in the galloping generation. Engineers should take some effective measures to control this harmful phenomenon due to the big possibility of the onset of galloping during the construction period.