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Improved complex filter applied in enhancing EFT/B immunity at a coal mine monitoring substation

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Journal of China University of Mining and Technology 2008年第1期18卷 22-26页

作者： SUN ji-ping MA Feng-ying LIChen State Key Laboratory of Coal Resources and Safe Mining China University of Mining ＆ Technology Beijing 100083 China College of Electronic Information and Control Engineering Shandong Institute of Light Industry Jinan Shandong 250100 China

A monitoring system is an important guarantee of safety in a production mine. However, not all monitoring substations pass the electrical fast transient/burst （EFT/B） immunity test and the explosion-proof test simultaneously. To enhance the immunity, the values of capacitance and inductance should be increased, which are actually limited by coal mine explosion-proof standards. Hence, for the first time, an active filter was applied in an electromagnetic interference （EMI） output filter. As a result, the interference within 30 MHz clearly weakened, but the frequency spectrum had a wide range. An EMI input filter and ferrite beads were adopted to restrain higher frequency interference. An output interference spectrogram of the substation was obtained with an analyzer. The results indicate that the improved complex filtering markedly help to control interference. With the support of improved complex filtering and other enhancing immunity means about I/O ports, the substation managed to pass both the EFT/B immunity test and the explosion-proof test synchronously. We conclude that improved complex filtering is of vital importance in enhancing the electromagnetic compatibilitv （EMC） of the coal mine monitoring system.

关键词： EFT/B coal mine monitoring substation immunity complex filter EMC

Spectral blueshift as a three-dimensional structure-ordering process

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Frontiers of physics 2017年第3期12卷 101-105页

作者： Jun-Ying Huang Zu-Hui Wu ji-ping Huang Department of Physics State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (MOE) Fudan University Shanghai 200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093 China

The transmission spectra of a TiO2-silicone oil suspension in an increasing external electric field are studied. As the electric field increases, the structure of the suspension changes from a disordered one to an ordered one. Interestingly, the transmission spectra blueshift in this structure-ordering process. Furthermore, the relative transmission spectra exhibit Fano-like asymmetric line shapes. The deviation ratio of each asymmetric line shape increases monotonously as the disorder of the suspension decreases. We suggest that this blueshift phenomenon can be used to characterize the disorder strength of three- dimensional systems.

关键词： disordered medium light propagation transmission spectrum blueshift

The Association between Lower Incisal Inclination and Morphology of the Supporting Alveolar Bone—A Cone-Beam CT Study

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International Journal of Oral Science 2009年第4期1卷 217-223页

作者： Quan Yu Xiao-gang Pan Guo-ping ji Gang Shen Shanghai Key Laboratory of Stomatology Department of Orthodontics Shanghai Ninth People＇s Hospital Affiliated toShanghai Jiao Tong University School of Medicine Shanghai China

Aim To investigate the relationship between the positioning of the lower central incisor and physical morphology of the surrounding alveolar bone. Methodology Thirty-eight patients （18 males, 20 females）, with mean age of 13.4 years, were included in this study. As part of orthodontic treatment planning the patients were required to take dental Cone-beam CT （CBCT） covering the region of lower incisors, the sur- rounding alveolar bone and the mandibular symphysis. The cephalometric parameters were designed and measured to indicate the inclination of lower central incisor and physical morphology of the adjacent alveolar bone. Computer-aided descriptive statistical analysis was performed using SPSS 15.0 software package for Windows. A correlation analysis and a linear regression analysis between the incisor inclination and the alveolar bone morphology were performed. Results Significant positive correlations were found between the lower central incisor inclination and the morphological contour of the alveolar bone （P〈0.05）. The lower central incisor root apex was closer to the lingual alveolar crest when it was buccally inclined. Conclusion The morphology of the alveolar bone may be affected by incisal inclination.

关键词： Cone-beam CT (CBCT) alveolar bone incisorinclination

Modeling of high-temperature reforming reactor based on interactive thermal control with a tail gas combustor

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Advances in Manufacturing 2016年第1期4卷 47-54页

作者： Dan Zhang Zhong Shao ji-ping Xin Ai-Jun Li Shanghai Key Laboratory of Mechanics in EnergyEngineering Institute of Applied Mathematics andMechanics Shanghai University Shanghai 200444People's Republic of China Research Center of Composite Materials ShanghaiUniversity Shanghai 200444 People's Republic of China

This paper proposes a method to model hydrocarbon reforming by coupling detailed chemical kinetics with complex computational fluid dynamics. The entire chemistry of catalyzed reactions was confined within the geometrically simple channels and modeled using the low-dimensional plug model, into which the interactive thermal control of the multi-channel reforming reactor has been implemented with a tail-gas combustor around the external surface of these catalytic channels. The geomet- rically complex flow in the tail gas combustor was simu- lated using FLUENT without involving any chemical reactions. The influences of the conditions at the reactor inlet such as the inlet gas velocity, the inlet gas composi- tion and the variety of hydrocarbons of each channel on gas conversions were investigated numerically. The impact of the tail gas combustor setup on the efficiency of the reforming reactor was also analyzed. Methane catalytic partial oxidation （CPOx） and propane steam reforming （SR） were used to illustrate the approach reported in the present work.

关键词： Computational fluid dynamics Reactionkinetics Catalytic partial oxidation Steam reforming

Spectral Representation Theory for Dielectric Behavior of Nonspherical Cell Suspensions

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Communications in Theoretical Physics 2002年第7期38卷 113-120页

作者： HUANG ji-ping YU Kin-Wah LEI Jun SUN Hong Department of Physics the Chinese University of Hong Kong Shatin NT Hong Kong China Department of Physics the Chinese University of Hong Kong Shatin NT Hong Kong China Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Applied Physics Shanghai Jiao Tong University Shanghai 200030 China Department of Physics University of California Berkeley California 94720-7300 U.S.A.

Recent experiments revealed that the dielectric dispersion spectrum of fission yeast cells in a suspension was mainly composed of two sub-dispersions. The low-frequency sub-dispersion depended on the cell length, while the high-frequency one was independent of it. The cell shape effect was simulated by an ellipsoidal cell model but the comparison between theory and experiment was far from being satisfactory. Prompted by the discrepancy, we proposed the use of spectral representation to analyze more realistic cell models. We adopted a shell-spheroidal model to analyze the effects of the cell membrane. It is found that the dielectric property of the cell membrane has only a minor effect on the dispersion magnitude ratio and the characteristic frequency ratio. We further included the effect of rotation of dipole induced by an external electric field, and solved the dipole-rotation spheroidal model in the spectral *** agreement between theory and experiment has been obtained.

关键词： dielectric relaxation, interfacial polarization, cell model

Cooperative Sensor Anomaly Detection Using Global Information

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Tsinghua Science and Technology 2013年第3期18卷 209-219页

作者： Rui Zhang ping ji Dinkar Mylaraswamy Mani Srivastava Sadaf Zahedi Intel-GE CareInnovations CAUS the Computer Science Department City University of New YorkNYUS Honeywell Aerospace Advanced Technology MNUS University of California Los AngelesCAUS

Sensor networks are deployed in many application areas nowadays ranging from environment monitoring, industrial monitoring, and agriculture monitoring to military battlefield sensing. The accuracy of sensor readings is without a doubt one of the most important measures to evaluate the quality of a sensor and its network. Therefore, this work is motivated to propose approaches that can detect and repair erroneous （i.e., dirty） data caused by inevitable system problems involving various hardware and software components of sensor networks. As information about a single event of interest in a sensor network is usually reflected in multiple measurement points, the inconsistency among multiple sensor measurements serves as an indicator for data quality problem. The focus of this paper is thus to study methods that can effectively detect and identify erroneous data among inconsistent observations based on the inherent structure of various sensor measurement series from a group of sensors. Particularly, we present three models to characterize the inherent data structures among sensor measurement traces and then apply these models individually to guide the error detection of a sensor network. First, we propose a multivariate Gaussian model which explores the correlated data changes of a group of sensors. Second, we present a Principal Component Analysis （PCA） model which captures the sparse geometric relationship among sensors in a network. The PCA model is motivated by the fact that not all sensor networks have clustered sensor deployment and clear data correlation structure. Further, if the sensor data show non-linear characteristic, a traditional PCA model can not capture the data attributes properly. Therefore, we propose a third model which utilizes kernel functions to map the original data into a high dimensional feature space and then apply PCA model on the mapped linearized data. All these three models serve the purpose of capturing the underlying phenomenon of a sen

关键词： wireless sensor network faulty detection kernel Principal Component Analysis (PCA)

Qifu-Yin attenuates AGEs-induced Alzheimer-like pathophysiological changes through the RAGE/NF-κB pathway

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Chinese Journal of Natural Medicines 2014年第12期12卷 920-928页

作者： WANG Shu-Yuan LIU ji-ping ji Wei-Wei CHEN Wen-jiao FU Qiang FENG Liang MA Shi-ping Department of Pharmacology of Chinese Materia Medica China Pharmaceutical University Department of Pharmacology Shaanxi University of Chinese Medicine Key Laboratory of Delivery Systems of Chinese Materia Medica Jiangsu Provincial Academy of Chinese Medicine

Qifu-Yin(QFY), a widely used formula of traditional Chinese medicine(TCM) derived from "jingyue Quanshu", is one of the most commonly used TCM prescriptions for the clinical treatment of Alzheimer disease. The role of advanced glycation end products(AGEs) and its receptor RAGE have attracted increasing attention as the pivotal role of Aβ has been questioned. The present study was designed to test the neuroprotective effects of QFY, and the possible mechanism in AGE-induced Alzheimer model rats. After injection of AGE in the CA3 area of the hippocampus, QFY(8.6, 4.3, and 2.15 g·kg–1), and a positive control drug donepezil(2 mg·kg–1) were administrated through gastric intubation to rats once daily for thirty consecutive days. Another positive control group was the AGE + anti-RAGE group, which was simultaneously injected with anti-RAGE antibody before AGE treatment. The control group, sham-operated group, as well as the AGE + anti-RAGE group received saline at the same dosage. The Morris water maze test and the step-down passive avoidance test were conducted to evaluate the cognitive function of the rats. The expression of RAGE and NF-κB were assayed by immunohistochemical staining. The levels of Aβ, TNF-α, and IL-1β in the hippocampus were measured by enzyme-linked immunosorbent assay(ELISA). The results showed that QFY could significantly attenuate the memory impairment induced by AGE, decrease the expressions of RAGE and NF-κB, and reduce the levels of Aβ, TNF-α, and IL-1β in the hippocampus in a dose-dependent manner. Also, the blockage of RAGE could significantly reduce the impairments caused by AGEs. In conclusion, QFY could attenuate AGEs-induced, Alzheimer-like pathophysiological changes. These neuroprotective effects might be related to the RAGE/NF-κB pathway and its anti-inflammatory activity.

关键词： Alzheimer’s disease Qifu-Yin Advanced glycation end products(AGEs) RAGE

Nonlinear changes in cold spell and heat wave arising from Arctic sea-ice loss

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Advances in Climate Change Research 2021年第4期12卷 553-562页

作者： SONG Mi-Rong WANG Shao-Yin ZHU Zhu LIU ji-ping Institute of Atmospheric Physics Chinese Academy of SciencesBeijing100029China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai519000China School of Geospatial Engineering and Science Sun Yat-sen UniversityZhuhai519000China University Corporation for Polar Research Zhuhai519000China Department of Atmospheric and Environmental Sciences University at AlbanyState University of New YorkAlbany12222USA

Whether Arctic sea-ice loss has significant impacts on climate extremes in mid-and high-latitudes remains *** we show the full response of cold and warm extremes under two Arctic sea-ice loss scenarios utilizing a coupled global climate model that permits the air-sea *** results show that the amount of Arctic sea-ice loss determines the spatial extent and magnitude of the weakening of atmospheric circulation in mid-and high-latitudes of the northern hemisphere,leading to nonlinear changes in cold and warm extremes.A relatively localized and moderate weakening of atmospheric circulation induced by the projected sea-ice loss in the next two decades would contribute to less winter cold extremes over the Northern Hemispheric *** risks of winter cold spells would be dramatically reduced as the amount of sea-ice loss is increased to the ice-free *** contrast,as sea-ice loss increases,the continental regions would have increased risk of heat waves over all mid-and high-latitudes.

关键词： Arctic sea ice Cold and warm extremes Coupled climate model

Finitely Generated Nilpotent Groups of Infinite Cyclic Commutator Subgroups

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Acta Mathematica Sinica,English Series 2020年第12期36卷 1315-1340页

作者： Jun LIAO He Guo LIU Xing Zhong XU ji ping ZHANG Hubei Key Laboratory of Applied Mathematics School of Mathematics and StatisticsHubei UniversityWuhan 430062P.R.China School of Mathematical Sciences Peking UniversityBeijing 100871P.R.China

The aim of this paper is to determine the structure and to establish the isomorphic invariant of the finitely generated nilpotent group G of infinite cyclic commutator *** the structure and invariant of the group which is the central extension of a cyclic group by a free abelian group offinite rank of infinite cyclic center,we provide a decomposition of G as the product of a generalized extraspecial Z-group and its *** using techniques of lifting isomorphisms of abelian groups and equivalent normal form of the generalized extraspecial Z-groups,we finally obtain the structure and invariants of the group G.

关键词： Nilpotent groups central extension isomorphic invariant