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Floor positioning method indoors with smartphone’s barometer

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Geo-Spatial Information Science 2019年第2期22卷 138-148,I0006页

作者： min Yu Feng Xue chao Ruan Hang Guo College of Computer Information and Engineering Jiangxi Normal UniversityNanchangChina Institute of Space Science and Technology Nanchang UniversityNanchangChina

This paper presents an indoor floor positioning method with the smartphone’s barometer for the purpose of solving the problem of low availability and high environmental dependence of the traditional floor positioning ***,an initial floor position algorithm with the“entering”detection algorithm has been ***,the user’s going upstairs or downstairs activities are identified by the characteristics of the air pressure ***,the moving distance in the vertical direction and the floor change during going upstairs or downstairs are estimated to obtain the accurate floor *** order to solve the problem of the floor misjudgment from different mobile phone’s barometers,this paper calculates the pressure data from the different cell phones,and effectively reduce the errors of the air pressure estimating the elevation which is caused by the heterogeneity of the mobile *** experiment results show that the average correct rate of the floor identification is more than 85%for three types of the cell phones while reducing environmental dependence and improving ***,this paper compares and analyzes the three common floor location methods–the WLAN Floor Location(WFL)method based on the fingerprint,the Neural Network Floor Location(NFL)methods,and the Magnetic Floor Location(MFL)method with our *** experiment results achieve 94.2%correct rate of the floor identification with Huawei mate10 Pro mobile phone.

关键词： Floor positioning smartphone’s barometer sensor calibration indoor location service

Existence of solutions for implicit fuzzy differential inclusions

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Applied Mathematics and Mechanics(English Edition) 2015年第3期36卷 401-416页

作者： chao min Nanjing HUANG Zhibin LIU Liehui ZHANG State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation School of Science Southwest Petroleum University Department of Mathematics Sichuan University

A class of implicit fuzzy differential inclusions （IFDIs） are introduced and studied. Some existence theorems under different conditions are proved with the selection theorems for the open situation and the closed situation, respectively. A viable solution for a closed IFDI is proved to exist under the tangential condition. As an application, an implicit fuzzy differential equation, which comes from the drilling dynamics in petroleum engineering, is analyzed numerically. The obtained results can improve and extend some known results for fuzzy differential inclusions （FDIs） and fuzzy differential equations （FDEs）, which might be helpful in the analysis of fuzzy dynamic systems.

关键词： implicit fuzzy differential inclusion (IFDI) fuzzy differential equation (FDE) selection theorem stacking theorem

Preference transfer model in collaborative filtering for implicit data

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Frontiers of Information Technology & Electronic Engineering 2016年第6期17卷 489-500页

作者： Bin JU Yun-tao QIAN min-chao YE Institute of Artificial Intelligence College of Computer Science and TechnologyZhejiang UniversityHangzhou 3100Z7China Health Information Center of Zhejiang Province Hangzhou 310006China

Generally, predicting whether an item will be liked or disliked by active users, and how much an item will be liked, is a main task of collaborative filtering systems or recommender systems. Recently, predicting most likely bought items for a target user, which is a subproblem of the rank problem of collaborative filtering, became an important task in collaborative filtering. Traditionally, the prediction uses the user item co-occurrence data based on users' buying behaviors. However, it is challenging to achieve good prediction performance using traditional methods based on single domain information due to the extreme sparsity of the buying matrix. In this paper, we propose a novel method called the preference transfer model for effective cross-domain collaborative filtering. Based on the preference transfer model, a common basis item-factor matrix and different user-factor matrices are *** user-factor matrix can be viewed as user preference in terms of browsing behavior or buying behavior. Then,two factor-user matrices can be used to construct a so-called ‘preference dictionary' that can discover in advance the consistent preference of users, from their browsing behaviors to their buying behaviors. Experimental results demonstrate that the proposed preference transfer model outperforms the other methods on the Alibaba Tmall data set provided by the Alibaba Group.

关键词： Recommender systems Collaborative filtering Preference transfer model Cross domain Implicit data

Propofol can Protect Against the Impairment of Learning-memory Induced by Electroconvulsive Shock via Tau Protein Hyperphosphorylation in Depressed Rats

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Chinese Medical Sciences Journal 2015年第2期30卷 100-107页

作者： wan-fu Liu chao Liu Department of Anesthesiology Fuzhou General Hospital of the People's Liberation Army Nanjing Military Region Department of Anesthesiology Tianjin Chest Hospital

Objective To explore the possible neurophysiologic mechanisms of propofol and N-methyl-Daspartate(NMDA) receptor antagonist against learning-memory impairment of depressed rats without olfactory bulbs. Methods Models of depressed rats without olfactory bulbs were established. For the factorial design in analysis of variance, two intervention factors were included: electroconvulsive shock groups(with and without a course of electroconvulsive shock) and drug intervention groups [intraperotoneal(ip) injection of saline, NMDA receptor antagonist MK-801 and propofol. A total of 60 adult depressed rats without olfactory bulbs were randomly divided into 6 experimental groups(n=10 per group): ip injection of 5 ml saline; ip injection of 5 ml of 10 mg/kg MK-801; ip injection of 5 ml of 10 mg/kg MK-801 and a course of electroconvulsive shock; ip injection of 5 ml of 200 mg/kg propofol; ip injection of 5 ml of 200 mg/kg propofol and a course of electroconvulsive shock; and ip injection of 5 ml saline and a course of electroconvulsive shock. The learning-memory abilities of the rats was evaluated by the Morris water maze test. The content of glutamic acid in the hippocampus was detected by high-performance liquid chromatography. The expressions of p-AT8Ser202 in the hippocampus were determined by Western blot analysis. Results Propofol, MK-801 or electroconvulsive shock alone induced learning-memory impairment in depressed rats, as proven by extended evasive latency time and shortened space probe time. Glutamic acid content in the hippocampus of depressed rats was significantly up-regulated by electroconvulsive shock and down-regulated by propofol, but MK-801 had no significant effect on glutamic acid content. Levels ofphosphorylated Tau protein p-AT8Ser202 in the hippocampus was up-regulated by electroconvulsive shock but was reduced by propofol and MK-801 alone. Propofol prevented learning-memory impairment and reduced glutamic acid content and p-AT8Ser202 levels induced by e

关键词： propofol Tau protein learning-memory abilities glutamate electroconvulsive therapy

The research on floe ice force acting on the"Xue Long"icebreaker based on synthetic ice test and virtual mass numerical method

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Journal of Hydrodynamics 2021年第2期33卷 271-281页

作者： Wei Guo Qiao-sheng Zhao Yu-kui Tian wan-chao Zhang State Key Laboratory of Hydrodynamics China Ship Scientific Research CenterWuxi 214082China School of Naval Architecture and Ocean Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

When the ice-going ships advance in the polar region,the navigation in the floe ice region is often encountered,the hull will suffer the high-frequency contact force produced by the floe ice,which will affect the navigation performance of the ***,it is necessary to predict the water and ice force acting on the hull *** this paper,the numerical simulation and experimental verification will be conducted for the polar scientific research ship-"Xue Long".Based on the computational fluid dynamics(CFD)and DEM theory,a virtual mass method is proposed to realize the predicting of the water and ice force and the simulation of the interaction phenomenon between the ice and hull,the numerical method is built to calculate the force acting on the *** the same time,the synthetic ice is used to carry out the experimental research on the advancing straight with different speeds and the oblique navigation with different drift *** optimal virtual mass coefficient is determined through the comparison and analysis of the numerical simulation and test results under typical *** to the optimal virtual mass coefficient,the numerical simulation is carried out with different speeds and drift angles,which is compared with the experiment more *** is found that the virtual mass method based on the combination of CFD and DEM can simulate the overturning and the sliding along the hull of the floe ice vividly,the relative error of the total resistance between model test and numerical method in advancing straight is almost within 10%,while the relative error of the total longitudinal force in oblique navigation is almost within 15%.

关键词： "Xue Long"ship synthetic ice model test computational fluid dynamics(CFD) DEM virtual mass method drift angle

Enhancement on Fatigue Property of Aluminum Alloy Welded Joint by Utilizing Trailing Peening

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Journal of Materials Science & Technology 2003年第z1期19卷 198-201页

作者： Changli wanG Zhimin wan min ZHAO Jitai NIU Harbin Institute of Technology Harbin 150001 China Harbin Institute of Technology Harbin 150001 China Harbin Institute of Technology Harbin 150001 China Harbin Institute of Technology Harbin 150001 China

The fatigue properties of 2024T3 aluminum alloy welded joint treated by different peening methods were examined. The different effects on fatigue performance of high strength aluminum welded joints were compared with each other by carry out a series tests using two different peening treatment samples. Results show that by applying synchronized hammer peening to the weak part of joint when weld was going on, trailing peening, may refine the grains near weld line, hardening the surface of weld toe and amend the distribution of residual stress. Because of these results the position of fracture of joint was moved from weld toe to weld line. Compared to the joints treated by peening after welding, the fatigue strength of weld joint treated by trailing peening was enhanced by more than 102%.

关键词： Fatigue strength, Cycling, Residual stresses, Trailing peening

Structural Restoration of Degraded LiFePO_(4)Cathode with Enhanced Kinetics Using Residual Lithium in Spent Graphite Anodes

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CCS Chemistry 2023年第5期5卷 1189-1201页

作者： min Fan Xin Chang Xin-Hai Meng chao-Fan Gu chao-Hui Zhang Qinghai Meng Li-Jun wan Yu-Guo Guo CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of Sciences(CAS)Beijing 100190 University of Chinese Academy of Sciences Beijing 100190

Enormous LiFePO_(4)(LFP)/graphite batteries retired from the market need urgent rational disposal and reutilization based on the degradation analysis of the evolutional mechanism for ***,Li inventory loss is one of the main reasons for the degradation of LFP-based *** reduced portion of lithium in a cathode is inevitably consumed to form solid electrolyte interphase or trapped in the ***,we propose a comprehensive strategy for battery recycling and conduct the work by simply regenerating the degraded LFP materials directly with the extracted lithium compounds from spent ***,inter-particle three-dimensional(3D)conductive networks are built via an in situ carbonization to reinforce the electronic conductivity of regenerated *** improved electrochemical performance was achieved in the regenerated LFP materials even compared with the pristine *** integrated recycling strategy not only brings more added value to the recycled materials by leveraging the recycling process but also aims to apply the concept of“treating waste with waste”and spur innovations in battery recycling technologies in the future.

关键词： spent Li-ion batteries solution relithiation regeneration in situ carbonization kinetic enhancement

OsPDR20 is an ABCG metal transporter regulating cadmium accumulation in rice

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Journal of Environmental Sciences 2024年第2期136卷 21-34页

作者： He Li chao Li Di Sun Zhi min Yang Department of Biochemistry and Molecular Biology College of Life SciencesNanjing Agricultural UniversityNanjing 210095China

Cadmium(Cd)is a non-essential toxic heavy metal,seriously posing high environmental risks to human *** genetic resources relevant to functional genes is important for understanding the metal absorption and accumulation in crops and bioremediation of Cd-polluted *** study investigated a functionally uncharacterized ATP binding cassette transporter G family(ABCG)gene encoding a Pleiotropic Drug Resistance 20(PDR20)type metal transporter which is localized to the plasma membrane of ***20 was transcriptionally expressed in almost all tissues and organs in lifespan and was strongly induced in roots and shoots of young rice under Cd *** expression of OsPDR20 in a yeast mutant ycf1 sensitive to Cd conferred cellular tolerance with less Cd *** of OsPDR20 by RNA interference(RNAi)moderately attenuated root/shoot elongation and biomass,with reduced chlorophylls in rice grown under hydroponic medium with 2 and 10μmol/L Cd,but led to more Cd accumulation.A field trial of rice grown in a realistic Cd-contaminated soil(0.40 mg/kg)showed that RNAi plants growth and development were also compromised compared to wild-type(WT),with smaller panicles and lower spikelet fertility but little effect on yield of ***,OsPDR20 suppression resulted in unexpectedly higher levels of Cd accumulation in rice straw including lower leaves and culm and *** results suggest that OsPDR20 is actively involved in Cd accumulation and homeostasis in rice *** increased Cd accumulation in the RNAi plants has the potential application in phytoremediation of Cd-polluted wetland soils.

关键词： Rice ABCG transporter Cadmium accumulation Phytoremediation

Active Damping of Milling Vibration Using Operational Amplifier Circuit

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Chinese Journal of Mechanical Engineering 2018年第5期31卷 58-65页

作者： Bashir Bala Muhammad min wan Yang Liu Heng Yuan School of Mechanical Engineering Northwestern Polytechnical University

The problem of chatter vibration is associated with adverse consequences that often lead to tool impairment and poor surface finished in a workpiece, and thus, controlling or suppressing chatter vibrations is of great significance to improve machining quality. In this paper, a workpiece and an actuator dynamics are considered in modeling and controller design. A proportional-integral controller(PI) is presented to control and actively damp the chatter vibration of a workpiece in the milling process. The controller is chosen on the basis of its highly stable output and a smaller amount of steady-state error. The controller is realized using analog operational amplifier circuit. The work has contributed to planning a novel approach that addresses the problem of chatter vibration in spite of technical hitches in modeling and controller design. The method can also lead to considerable reduction in vibrations and can be beneficial in industries in term of cost reduction and energy saving. The application of this method is verified using active damping device actuator(ADD) in the milling of steel.

关键词： Active damping Anti-windup Bending moment Milling process Workpiece vibration Operational amplifier Proportional integral controller