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Mechanical properties and acoustic emission characteristics of thick hard roof sandstone in Shendong coal field

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International Journal of Coal science & Technology 2017年第2期4卷 147-158页

作者： Huigui Li Huamin Li School of Energy science and Engineering HenanPolytechnic University Jiaozuo 454000 Henan People'sRepublic of China Opening Project of Key Laboratory of Deep MineConstruction Henan Polytechnic UniversityJiaozuo 454000 Henan People's Republic of China

The mechanical properties and acoustic emission characteristics of thick hard roof sandstone were investigated. Samples were taken from the 30.87-m thick sandstone roof in a mine in the Shengdong coal field, China. Firstly, the composition and microscopic characteristics were analyzed by XRD and FE-SEM, respectively. Moreover, the indirect tensile test, uniaxial compression test, three axis compression experiment and AE test are carried out by using RMT-150C mechanics experiment system with DSS-8B AE test system. The experiment results indicate that the main framework particles of sandstone are quartz and feldspar, and mainly quartz. Cements are mainly pyrite, kaolinite, chlorite and zeolite cross needle, clinochlore, and clay minerals. The microstructure of sandstone is very dense, with few pores and high cementation degree. The tensile strength, compressive strength and elastic modulus of sandstone are 4.825, 85.313 MPa, 13.814 GPa, respectively, so the sandstone belongs to hard rock. The AE cumulative counts of sandstone can be divided into three phases： relatively flat growth period, rapid growth period and spurt period. The signal strength of AE waveform can be used as a warning signal. In the tensile fracture zone, the warning value is 0.4 mV, and in the compression shear failure zone, it is 4 mV. The numbers of cumulative counts of AE under different stress conditions have obvious difference. Moreover, the growth of cumulative counts of acoustic emission is more obvious when the stress is more than 60% of the peak stress.

关键词： Mechanical Acoustic emission (AE) Sandstone X-ray diffractometer (XRD) Field emission scanningelectron microscope (FE-SEM)

Sensor radiation interception risk control in target tracking

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Defence Technology（防务技术） 2020年第3期16卷 695-704页

作者： Ce Pang Gan-lin Shan Wei-ning Ma Gong-guo Xu Army Engineering University Shijiazhuang CampusShijiazhuangHebei050003China

This paper is mainly on the problem of radiation interception risk control in sensor network for target ***,the sensor radiation interception risk is defined as the product of the interception probability and the cost caused by the ***,the radiation interception probability model and cost model are established,based on which the calculation method of interception risk can be ***,a sensor scheduling model of radiation risk control is established,taking the minimum interception risk as the objective *** the Hungarian algorithm is proposed to obtain sensor scheduling ***,simulation experiments are mad to prove the effectiveness of the methods proposed in this paper,which shows that compared with the sensor radiation interception probability control method,the interception risk control method can keep the sensor scheduling scheme in low risk as well as protect sensors of importance in the sensor network.

关键词： Radio frequency stealth Target tracking Interception probability Interception risk Hungary algorithm

Research on fault detection method for heat pump air conditioning system under cold weather

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chinese Journal of Chemical Engineering 2017年第12期25卷 1812-1819页

作者： Liangliang Sun Jianghua Wu Haiqi Jia Xuebin Liu Information and Control Engineering Shenyang Jianzhu University Electrical Engineering University of Connecticut

Building energy consumption accounts for nearly 40% of global energy consumption, HVAC （Heating, Ventilating, and Air Conditioning） systems are the major building energy consumers, and as one type of HVAC systems, the heat pump air conditioning system, which is more energy-efficient compared to the traditional air conditioning system, is being more widely used to save energy. However, in northern China, extreme climatic conditions increase the cooling and heating load of the heat pump air conditioning system and accelerate the aging of the equipment, and the sensor may detect drifted parameters owing to climate change. This non-linear drifted parameter increases the false alarm rate of the fault detection and the need for unnecessary troubleshooting. In order to overcome the impact of the device aging and the drifted parameter, a Kalman filter and SPC （statistical process control） fault detection method are introduced in this paper. In this method, the model parameter and its standard variance can he estimated by Kalman filter based on the gray model and the real-time data of the air conditioning system. Further, by using SPC to construct the dynamic control limits, false alarm rate is reduced. And this paper mainly focuses on the cold machine failure in the component failure and its soft fault detection. This approach has been tested on a simulation model of the ＂Sino-German Energy Conservation Demonstration Center＂ building heat pump air-conditioning system in Shenyang, China, and the results show that the Kalman filter and SPC fault detection method is simple and highly efficient with a low false alarm rate, and it can deal with the difficulties caused by the extreme environment and the non-linear influence of the parameters, and what＇s more, it provides a good foundation for dynamic fault diagnosis and fault prediction analysis.

关键词： Fault detection Cold machine Kalman filter Statistical process control Dynamic control

An approach for predicting digital material consumption in electronic warfare

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Defence Technology（防务技术） 2020年第1期16卷 263-273页

作者： Xiong Li Xiao-dong Zhao Wei Pu Military Exercise and Training Center Army Academy of Armored ForcesBeijing 100072China

Electronic warfare is a modern combat mode,in which predicting digital material consumption is a key for material requirements planning(MRP).In this paper,we introduce an insensitive loss function(ε) and propose a ε-SVR-based prediction ***,we quantify values of influencing factors of digital equipments in electronic warfare and a small-sample data on real consumption to form a real combat data set,and preprocess it to construct the sample ***,we establish the ε-SVR-based prediction model based on "wartime influencing factors-material consumption" and perform model *** case study,we give 8 historical battle events with battle damage data and predict 3 representative kinds of digital materials by using the proposed *** results illustrate its higher accuracy and more convenience compared with other current *** data acquisition controller prediction as an example,our model has better prediction performance(RMSE=0.575 7,MAPE(%)=12.037 6 and R^2=0.996 0) compared with BP neural network model(RMSE=1.272 9,MAPE(%)=23.577 5 and R^2=0.980 3) and GM(1,1) model(RMSE=2.095 0,MAPE(%)=24.188 0 and R^2=0.946 6).The fact shows that the approach can be used to support decision-making for MRP in electronic warfare.

关键词： Electronic warfare Support vector regression(SVR) Prediction model Decision-making

Knowledge-oriented modeling for influencing factors of battle damage in military industrial logistics:An integrated method

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Defence Technology（防务技术） 2020年第3期16卷 571-587页

作者： Xiong Li Xiao-dong Zhao Wei Pu Military Exercise and Training Center Army Academy of Armored ForcesBeijing 100072China

Modeling influencing factors of battle damage is one of essential works in implementing military industrial logistics simulation to explore battle damage laws ***,one of key challenges in designing the simulation system could be how to reasonably determine simulation model input and build a bridge to link battle damage model and battle damage laws *** this paper,we propose a novel knowledge-oriented modeling method for influencing factors of battle damage in military industrial logistics,integrating conceptual analysis,conceptual modeling,quantitative modeling and simulation *** conceptualize influencing factors of battle damage by using the principle of hierarchical decomposition,thus classifying the related battle damage knowledge ***,we construct the conceptual model of influencing factors of battle damage by using Entity-Relations hip approach,thus describing their interactions ***,we extract the important influencing factors by using social network analysis,thus evaluating their importance quantitatively and further clarifying the elements of ***,we develop an agent-based military industry logistics simulation system by taking the modeling results on influencing factors of battle damage as simulation model input,and obtain simulation model output,i.e.,new battle damage laws knowledge,thus verifying feasibility and effectiveness of the proposed *** results show that this method can be used to support human decision-making and action.

关键词： Battle damage Industrial logistics Entity-relationship approach Social network analysis Agent-based simulation

Enhanced Branch Simulation to Improve RAPID in Optical Region Using RAMI Scenes

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Journal of Remote Sensing

Journal of Remote Sensing 2023年第1期3卷 178-197页

作者： Huaguo Huang Jianbo Qi Linyuan Li State Forestry and Grassland Administration Key Laboratory of Forest Resources and Environmental Management Beijing Forestry UniversityBeijing 100083People’s Republic of China

To improve the simulation accuracy of vegetation canopy reflectance in optical bands,the Radiosity Applicable to Porous IndiviDual objects(RAPID)model has been upgraded to better deal with branches in the latest *** versions of RAPID(RAPID1 and RAPID3)neglected branches in porous objects in optical bands,while RAPID2 emphasized them in microwave *** inconsistency needed to be addressed to establish a unified radiosity-based simulation *** incorporating branches in RAPID4,we have improved several aspects of the model,including the random dynamic projection process,the equivalent reflectance or transmittance,the single scattering estimation,the multiple scattering solution,and the bidirectional reflectance factor(BRF)***-dimensional trees from the fifth RAdiation transfer Model Intercomparison(RAMI-V)have been used to test the contribution of branches on *** with a ray-tracing-based LESS model(the LargE-Scale remote sensing data and image Simulation framework)on RAMI-V scenes show a general agreement on BRF(R^(2)≥0.96 and root mean square error ranging from 0.014 to 0.054).The major biases occur in a realistic scene(i.e.,HET51_WWO_TLS)created from terrestrial laser scanning *** analysis has been conducted to show the branch contribution on BRF in optical *** considering dense branches,the BRF error can exceed 0.1.

关键词： scattering RAPID reflectance

Electroacupuncture diminishes P2X_2 and P2X_3 purinergic receptor expression in dorsal root ganglia of rats with visceral hypersensitivity

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Neural Regeneration Research 2013年第9期8卷 802-808页

作者： Zhijun Weng Luyi Wu Yuan Lu Lidong Wang Linying Tan Ming Dong Yuhu Xin Shanghai Academy of Traditional chinese Medicine Fudan University Shanghai Cancer Center

Electroacupuncture at Shangjuxu （ST37） and Tianshu （ST25） can improve visceral hypersensitivity in rats. Colorectal distension was used to establish a rat model of chronic visceral hypersensitivity. Immunohistochemistry was used to detect P2X2 and P2X3 receptor expression in dorsal root ganglia from rats with chronic visceral hypersensitivity. Results demonstrated that abdominal withdrawal reflex scores obviously increased following establishment of the model, indicating visceral hypersensitivity. Simultaneously, P2X2 and P2X3 receptor expression increased in dorsal root ganglia. After bilateral electroacupuncture at Shangjuxu and Tianshu, abdominal withdrawal reflex scores and P2X2 and P2X3 receptor expression decreased in rats with visceral hypersensitivity. These results indicated that electroacupuncture treatment improved visceral hypersensitivity in rats with irritable bowel syndrome by reducing P2X2 and P2X3 receptor expression in dorsal root ganglia.

关键词： neural regeneration acupuncture and moxibustion P2X2 P2X3 visceral hypersensitivity irritablebowel syndrome electroacupuncture P2 purinergic receptors abdominal withdrawal reflex scoresacupuncture and moxibustion peripheral nerve injury grants-supported paper photographscontaining paper neuroregeneration

AN INTERVAL METHOD FOR STUDYING THE RELATIONSHIP BETWEEN THE AUSTRALIAN DOLLAR EXCHANGE RATE AND THE GOLD PRICE

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Journal of Systems science & Complexity 2012年第1期25卷 121-132,132+131页

作者： Ai HAN K.K.LAI Shouyang WANG Shanying XU Academy of Mathematics and Systems sciences Chinese Academy of Sciences Department of Management sciences City University of Hong KongTat Chee AvenueKowloonHong KongChina

This paper proposes an interval method to explore the relationship between the exchange rate of Australian dollar against US dollar and the gold price, using weekly, monthly and quarterly data. With the interval method, interval sample data are formed to present the volatility of variables. The ILS approach is extended to multi-model estimation and the computational schemes are provided. The empirical evidence suggests that the ILS estimates well characterize how the exchange rate relates to the gold price, both in the long-run and short-run. The comparison between the interval and point methods indicates that the difference between the OLS and the ILS estimates is increasing from weekly data to quarterly data, since the lowest frequency point data lost the most information of volatility.

关键词： Exchange rate gold price interval method.

Adding Fuel to the Fire by Increased GABAergic Inhibition:A Seizure-Amplifying Nigra-Parafascicular Pathway

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Neuroscience Bulletin 2021年第1期37卷 135-137页

作者： Yeping Ruan Rongrong Chen Jie Yu Chengping Wen Zhenghao Xu Zhejiang chinese Medical University Hangzhou 310053China School of Basic Medical science Zhejiang Chinese Medical UniversityHangzhou 310053China

Epilepsy is a common neurological disorder characterized by recurrent *** anti epileptic drugs (AEDs)work by regulating the balance of the excitatory glutamatergic and inhibitory GABAergic ***,the current AEDs cannot successfully control seizures in most (>70%) patients with temporal lobe epilepsy (TLE)[1],in whom seizures typically begin in the *** may be caused by changes in the synaptic efficacy and remodeling of neural circuits,such as alterations in the distribution/expression of GABA_A receptor subunits and mossy-fiber *** *** Gale and colleagues originally described the seizure-modulating effects of nigral GABAergic transmission in the early 1980s [2]。

关键词： epilepsy alterations AEDs