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Sensitive properties of In-based compound semiconductor oxide to Cl_2 gas

Journal of Semiconductors 2009年第3期30卷 83-86页

作者：赵文杰施云波修德斌雷廷平冯侨华王立全 School of Applied Sciences Harbin University of Science and Technology Mechanical Engineering Center for Post-doctoral Studies Harbin Engineering University School of Measurement Control Tech & Communications Engineering Harbin University of Science and Technology

Aiming at detecting Cl2 gas, this study was made on how to make In-based compound semiconductor oxide gas sensor. The micro-property and sensitivity of In-based gas sensing material were analyzed and its gas sensitive mechanism was also discussed. Adopting constant temperature chemical coprecipitation, the compound oxides such as In-Nb, In-Cd and In-Mg were synthesized, respectively. The products were sintered at 600 ℃ and characterized by the Scanning Electron Microscope （SEM）, showing the grain size almost about 50-60 nm. The test results show that the sensitivities of In-Nb, In-Cd and In-Mg materials under the concentration of 50 × 10^-6 in Cl2 gas are above 100 times, 4 times and 10 times, respectively. The response time of In-Nb, In-Cd and In-Mg materials is about 30, 60 and 30 s, and the recovery time less than 2, 10 and 2 min, respectively. Among them, the In-Nb material was found to have a relatively high conductivity and ideal sensitivity to Cl2 gas, which showed rather good selectivity and stability, and could detect the minimum concentration of 0.5 × 10^-6 with the sensitivity of 2.2, and the upper limit concentration of 500 × 10^-6. The power loss of the device is around 220 mW under the heating voltage of 3 V.

关键词： In2O3 Nb2O5, sensitive property chlorine gas sensor

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Synthesis of organic semiconductor hexadecachloro zinc phthalocyanine and its gas sensitivity

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Journal of Semiconductors 2009年第3期30卷 78-82页

作者：施云波雷廷平李赞修德斌赵文杰冯侨华王立权 Mechanical Engineering Center for Post-doctoral Studies Harbin Engineering University School of Measurement Control Tech & Communications Engineering Harbin University of Science and Technology School of Applied Sciences Harbin University of Science and Technology School of Life Science and Chemistry Harbin University

Due to the difficulty in synthesizing perhalogenated metallophthalocyanine, the method of ammonium molybdate solid phase catalysis was introduced, and by using tetrachlorophthalic anhydride and urea as the raw materials, hexadecachloro zinc phthalocyanine （ZnPcCl16） was synthesized. Components of the composite were analyzed by energy spectrum, and its functional group structures and absorption peaks were characterized by IR and UV-vis spectroscopy. The thin films of gas sensors were prepared in a vacuum evaporation system and evaporated onto SiO2 substrates, where sensing electrodes were made by MEMS micromachining. The optimal conditions for the films are： substrate temperature of 150 ℃ evaporation current of 95 A and film thickness of 50 nm. The result showed that the sensors were ideally sensitive to Cl2 gas and could detect the minimum concentration of 0.3 ppm.

关键词： hexadecachloro zinc phthalocyanine organic semiconductor gas sensitivity

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Asynchronously Switched H∞ Tracking control for Cascade Switched Nonlinear Systems 35

Asynchronously Switched H∞ Tracking Control for Cascade Swi...

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第35届中国控制会议

作者： Dong Xiaoxiao Chang Linyan Dalian University of Technology Post-doctoral Research Station of Control Science and Engineering Shenyang University of Technology School of Science

ISBN: (纸本)9789881563910

In the present work, the H output tracking problem for a class of cascade switched nonlinear systems was studied under asynchronous switching. Sufficient conditions of the solvability of the asynchronous output tracking problem are developed using average dwell time method. The controllers are designed to achieve the tracking performances. At last, a simulation example was performed to validate our approach.

关键词： Output tracking cascade switched nonlinear systems asynchronous switching

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Key technologies and engineering practices for soft-rock protective seam mining

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International Journal of Mining science and Technology 2020年第6期30卷 889-899页

作者： Xiang Cheng Guangming Zhao Yingming Li Xiangrui Meng Qingyi Tu State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines Anhui University of Science and TechnologyHuainan 232001China Geological Resources and Geological Engineering Post-Doctoral Flow Station Anhui University of Science and TechnologyHuainan 232001China Post-Doctoral Research Station Huaibei Mining Corporation LimitedHuaibei 235006China

Severe gas disasters in deep mining areas are increasing,and traditional protective coal seam mining is facing significant *** paper proposes an innovative technology using soft rock as the protective seam in the absence of an appropriate coal *** on the geological engineering conditions of the new horizontal first mining area of Luling Coal Mine in Huaibei,China,the impacts of different mining parameters of the soft-rock protective seam on the pressure-relief effect of the protected coal seam were analyzed through numerical *** unit stress of the protected coal seam,which was less than half of the primary rock stress,was used as the mining stress pressure-relief *** optimized interlayer space was found to be 59 m for the first soft-rock working face,with a 2 m mining thickness and 105 m face *** physicochemical characteristics of the orebody were analyzed,and a device selection framework for the soft-rock protective seam was *** equipment for the working face was selected,including the fully-mechanized hydraulic support and coal cutter.A production technology that combined fully-mechanized and blasting-assisted soft-rock mining was *** practices demonstrated that normal circulation operation can be achieved on the working face of the soft-rock protective seam,with an average advancement rate of 1.64 m/*** maximum residual gas pressure and content,which were measured at the cut hole position of the protected coal seams(Nos.8 and 9),decreased to 0.35 MPa and 4.87 m^3/t,*** results suggested that soft-rock protective seam mining can produce a significant gas-control effect.

关键词： Gas outburst hazard Soft-rock protective seam Pressure-relief Three-machine optimization Blasting-assisted mining Gas extraction

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Research on matching accuracy of underwater terrain matching algorithm based on unscented kalman filter 2019

Research on matching accuracy of underwater terrain matching...

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4th International Conference on Mathematics and Artificial Intelligence, ICMAI 2019

作者： Lu, Xiong Jian, Shen Xiaowen, Bi Department of Radar System OrdnanceNCO. Academy Army engineering university Wuhan China Post-doctoral program on control science and engineering Naval University of Engineering Wuhan China

ISBN: (纸本)9781450362580

UT transform is the core step of unscented kalman filter (UKF) algorithm. The Sigma sampling type of UT transform has great influence on the computational complexity, state estimation accuracy and computational efficiency of UKF-based terrain matching algorithm. In order to obtain the high precision terrain matching method which is suitable for engineering application, the Comparative analysis of three kinds of UKF-based terrain matching algorithms was carried out in this paper. Firstly, the UKF-based underwater terrain matching model was given. Secondly, the principle and the performance characteristics of scaled sampling method, Cubature sampling method, Gauss- Hermite sampling methods were analyzed. The filtering precision factors of symmetric unscented Kalman filter(SUKF), Cubature unscented Kalman filter(CKF), Gauss-Hermite Kalman Filter(GHKF) was studied from the algorithm principle, Thirdly, The computer simulation was performed using univariate nonstationary growth model(UNGM) to test the previous analysis conclusions. Finally underwater terrain matching simulation model was established, and the comparative analysis of matching acuraccy was carried out based on SITAN, SUKF, CKF and GHKF, the matching effect of underwater terrain matching algorithm is obtained. The simulation results show that the UKF algorithm based on symmetric sampling strategy has better filtering precision and less computational complexity which is suitable for the filtering core of underwater terrain matching algorithm. © 2019 Association for Computing Machinery.

关键词： Kalman filters

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A new method of terrain self-adaptive matching algorithm for autonomous underwater vehicle 4

A new method of terrain self-adaptive matching algorithm for...

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2019 4th International Conference on Intelligent Computing and Signal Processing, ICSP 2019

作者： Lu, Xiong Jian, Shen Xiaowen, Bi Department of Radar System Ordnance NCO Academy of Army Engineering University Wuhan430075 China Post-doctoral Program on Control Science and Engineering Naval University of Engineering Wuhan430033 China

As different underwater terrain features will affect the accuracy of unscented Kalman filter terrain matching algorithm, a new terrain self-adaptive matching method is proposed which adjusts sigma point distribution by terrain features. The connection between sigma point distribution distance and three basic terrain features were analysed. Positioning error range were calculated using navigation positioning errors and underwater digital map. Terrain elevation standard deviation was used to characterize the information quantity of decision region. Scaling parameter was adjusted using linear mapping method and sigma point distribution distance was determined by terrain features. The simulation results proved better terrain adaptability and positioning precision of improved self-adaptive matching algorithm. © 2019 IOP Publishing Ltd. All rights reserved.

关键词： Autonomous underwater vehicles

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Modeling the effect of population growth on stream nutrient concentration in turkey creek watershed using the WARMF model

Modeling the effect of population growth on stream nutrient ...

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11th National Symposium on Individual and Small Community Sewage Systems

作者： Geza, M. McCray, John E. Post Doctoral Researcher Environmental Science and Engineering Division Colorado School of Mines Department of Hydrologic Science and Engineering Program Environmental Science and Engineering Division Colorado School of Mines

Population growth and water quality in the foothills of Jefferson County are of concern to County's Board of County Commissioners and the Planning and Zoning Department. The Department desires to meet the needs of residents for adequate supplies of good quality water. The Turkey Creek watershed is representative of the foothills portions of Jefferson County. In 2001 population in the Turkey Creek watershed is estimated at 11,064 residents with projected population growth, using a 2-percent per year rate, at 13,186 residents in 2010, and 15,313 residents in 2020. Wtershed based non-point source (NPS) studies have usually ignored the impact of on-site septic systems (OWS) on the quality of surface water. However, OWS can be a substantial source of nutrients to surface waters. Point discharges from Wastewater Treatment Plants (WWTPs) can also contribute to stream pollution from nutrients if treatment efficiency at the WWTP is low. Several models can handle point source discharges from WWTPs. Evaluating nutrient loading from septic systems to streams is a challenging task because most NPS models are not specifically developed to track the fate and transport of nutrients from on-site systems. The Watershed Analysis Risk Management Framework (WARMF) model is adapted to simulate on-site septic systems loading. The 122.2 square-kilometer Turkey Creek watershed is located in Jefferson County, southwest of Denver, Colorado. The topography is mostly steep with elevations ranging from about 1800 m to 3200 m. WARMF model hydrologic calibration was performed using data from the gage station located at Turkey Creek at mouth of canyon near Morrison. Water-quality data collected during flow calibration period was used to guide water quality calibration. The base case scenario is established at year 2001. The scenarios in this study are population at 1990 and projected population at year 2010. The scenario runs will also provide the contributions of different water treatment options

关键词： Nutrients

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A low-profile vertical polarized omnidirectional radiated and broadband printed antenna

A low-profile vertical polarized omnidirectional radiated an...

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2016 IEEE Antennas and Propagation Society International Symposium, APSURSI 2016

作者： Shu, Lin Guanjun, Liu Yuwei, Zhang Hua, Zong Shuang, Qiu Shengchang, Lan Denisov, Alexander Control Science and Engineering Post-Doctoral Research Center Harbin China School of Electronics and Information Engineering Harbin Institute of Technology Harbin China

ISBN: (纸本)9781509028863

In this paper, a low-profile vertical polarized omnidirectional radiated and broadband printed antenna was proposed. This antenna forms a transmission lines structure similar with parallel lines by using metal vias and coaxial feed inner conductor. Then the distributed inductances and capacitances of transmission lines are used to yield resonance with loaded capacitance of antenna itself. Therefore, this structure can realize wide range of working frequency and has omnidirectional radiation characteristics. The simulated results by CST Microwave Studio software indicate that the reflection coefficient of the antenna is less than -10dB and relative bandwidth is up to 49% from 2.40GHz to 3.95GHz. Also, the corresponding omnidirectional gain is up to the range from 1.3 dBi to 4.2 dBi. The dimension of this vertical polarized antenna is 10mm on the polarization direction, which is only 8% of the lowest working frequency corresponding to the wavelength. Hence, the antenna achieves well low-profile effects. The working frequency band covers WLAN/WiMAX bandwidths. © 2016 IEEE.

关键词： broadband low-profile omnidirectional radiated printed antenna

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Chlorine gas sensors using hybrid organic semiconductors of PANI/ZnPcCl_(16)

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Journal of Semiconductors 2010年第8期31卷 88-92页

作者：雷廷平施云波吕文龙刘洋陶巍袁鹏亮林立伟孙道恒王立权 College of Physics and Mechanical & Electrical Engineering Xiamen University Mechanical Engineering Center for Post-doctoral Studies Harbin Engineering University Higher Educational Key Laboratory for Measuring & Control Technology and Instrumentations of Heilongjiang Province School of Measurement Control Tech & Communications EngineeringHarbin University of Science and Technology Qingyang Secondary Specialized School of Science and Technology Department of Mechanical Engineering and Berkeley Sensor and Actuator Center University of CaliforniaBerkeleyCalifornia 94720USA

PANI/ZnPcCl_（16）（polyaniline doped with sulfosalicylic acid/hexadecachloro zinc phthalocyanine） powders were vacuum co-deposited onto Si substrates,where Pt interdigitated electrodes were made by *** PANI/ZnPcCl_（16） films were characterized and analyzed by SEM,and the influencing factors on its intrinsic performance were analyzed and sensitivities of the sensors were investigated by exposure to chlorine（Cl_2） *** results showed that powders prepared with a stoichiometric ratio of（ZnPcCl_（16））_（0.6）（PANI）_（0.4） had a preferential sensitivity to Cl_2 gas, superior to those prepared otherwise;the optimal vacuum co-deposition conditions for the films are a substrate temperature of 160℃,an evaporation temperature of 425℃and a film thickness of 75 nm;elevating the operation temperature （above 100℃） or increasing the gas concentration（over 100 ppm） would improve the response characteristics,but there should be upper levels for ***,the gas sensing mechanism of PANI/ZnPcCl_（16） films was also discussed.

关键词： PANI/ZnPcCl_(16) hybrid organic semiconductors chlorine gas sensors vacuum co-deposition

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Research on Matching Accuracy of Underwater Terrain Matching Algorithm Based on State Augmented Unscented Kalman Filter 3

Research on Matching Accuracy of Underwater Terrain Matching...

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3rd IEEE International Conference on Robotics and Automation sciences, ICRAS 2019

作者： Lu, Xiong Jian, Shen Haitao, Liu Department of Radar System Ordnance NCO Academy of Army Engineering University Wuhan China Post-doctoral Program on Control Science and Engineering Naval University of Engineering Wuhan China Department of Basic Mathematics Naval University of Engineering Wuhan China

ISBN: (纸本)9781728108537

Underwater high-precision positioning is the basis of safe sailing and smooth operation for underwater autonomous vehicle (AUV). With the continuous expansion of marine surveys, the requirements for navigation accuracy of AUVs are also increasing. As the unscented Kalman filter (UKF)-based terrain matching method can meet the high-precision positioning demand of underwater navigation, it becomes one of the hot research content in recent years. However, due to the insufficient robustness of UKF algorithm, under the condition of non-additive state noise, the initial distribution of Sigma points is prone to be unreasonable, which will reduce filter accuracy and even cause the recursive result divergence. In order to improve the accuracy and robustness of the underwater terrain matching algorithm, this paper introduces the method of nonlinear filtering state expansion. The system noise and measurement noise information are added into the system state matrix and the variance matrix, and obtains the state expansion UKF-based terrain matching algorithm. Since the noise and the estimation parameters are both participating in the filtering operation, the inaccurate prediction influence of initial noise can be reduced, and finally improves the accuracy and applicability of the underwater terrain matching algorithm. © 2019 IEEE.

关键词： Kalman filters

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