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Delayed treatment of diabetic foot ulcer in patients with type 2 diabetes and its prediction model

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World Journal of Diabetes 2024年第10期15卷 2070-2080页

作者： hui chen Ying Xi Department of General Practice Shaanxi Provincial People's HospitalXi’an 710000Shaanxi ProvinceChina

BACKGROUND Diabetic foot(DF)is a serious complication of type 2 *** study aimed to investigate the factors associated with DF occurrence and the role of delayed medical care in a cohort of patients with type 2 *** To reveal the impact of delayed medical treatment on the development of DF in patients with type 2 diabetes and to establish a predictive model for *** In this retrospective cohort study,292 patients with type 2 diabetes who underwent examination at our hospital from January 2023 to December 2023 were selected and divided into the DF group(n=82,DF)and nondiabetic foot group(n=210,NDF).Differential and correlation analyses of demographic indicators,laboratory parameters,and delayed medical treatment were conducted for the two *** regression was applied to determine influencing *** operating characteristic(ROC)analysis was performed,and indicators with good predictive value were selected to establish a combined predictive *** The DF group had significantly higher body mass index(BMI)(P<0.001),disease duration(P=0.012),plasma glucose levels(P<0.001),and HbA1c(P<0.001)than the NDF *** NDF group had significantly higher Acute Thrombosis and Myocardial Infarction Health Service System(ATMHSS)scores(P<0.001)and a significantly lower delayed medical treatment rate(72.38%vs 13.41%,P<0.001).BMI,duration of diabetes,plasma glucose levels,HbA1c,diabetic peripheral neuropathy,and nephropathy were all positively correlated with DF *** scores were negatively correlated with delayed time to seek medical *** logistic regression model revealed that BMI,duration of diabetes,plasma glucose levels,HbA1c,presence of diabetic peripheral neuropathy and nephropathy,ATMHSS scores,and delayed time to seek medical treatment were influencing factors for *** analysis indicated that plasma glucose levels,HbA1c,and delayed medical treatment had good predictive value with an area under the curve

关键词： Delayed treatment Medical attention Diabetic foot ulcer Type 2 diabetes Prediction model

Estimation of Vehicle Pose and Position with Monocular Camera at Urban Road Intersections

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Journal of Computer Science & Technology 2017年第6期32卷 1150-1161页

作者： Jin-Zhao Yuan hui chen Bin Zhao Yanyan Xu School of Information Science and Engineering Shandong University Jinan 250100 China Beijing Xuanlongding-xun Technology Co. Ltd. Beijing 100041 China Department of Civil and Environmental Engineering Massachusetts Institute of Technology Cambridge 02139 U.S.A.

With the rapid development of urban, the scale of the city is expanding day by day. The road environment is becoming more and more complicated. The vehicle ego-localization in complex road environment puts forward imperative requirements for intelligent driving technology. The reliable vehicle ego-localization, including the lane recognition and the vehicle position and attitude estimation, at the complex traffic intersection is significant for the intelligent driving of the vehicle. In this article, we focus on the complex road environment of the city, and propose a pose and position estimation method based on the road sign using only a monocular camera and a common GPS （global positioning system）. Associated with the multi-sensor cascade system, this method can be a stable and reliable alternative when the precision of multi-sensor cascade system decreases. The experimental results show that, within 100 meters distance to the road signs, the pose error is less than 2 degrees, and the position error is less than one meter, which can reach the lane-level positioning accuracy. Through the comparison with the Beidou high-precision positioning system L202, our method is more accurate for detecting which lane the vehicle is driving on.

关键词： vehicle pose and position estimation road sign detection homograph matrix road intersection urban envi-ronment

Three-dimensional numerical simulation of soft/hard composite-coated textured tools in dry turning of AISI 1045 steel

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Advances in Manufacturing 2019年第2期7卷 133-141页

作者： Yun-Song Lian chen-Liang Mu Ming Liu hui-Feng chen Bin Yao Department of Mechanical and Electrical Engineering Xiamen University Xiamen 361102 Fujian People's Republic of China

A structural model of a soft/hard compositecoated textured (SHCCT) tool was proposed and substantiated by a three-dimensional numerical simulation. Its dry turning performance as applied to AISI-1045 steel was analyzed via three-factor five-level orthogonal experiments for different coating parameters, including coating thickness, coating material, and thickness ratio of the soft and hard coatings. In addition, the cutting performance of the proposed SHCCT tool was compared with those of uncoated non-textured, coated non?textured, and uncoated textured tools, and its superiority was proved by the significant reductions in the cutting force, and specifically, the cutting temperature. The optimal results were provided by the SHCCT tool with a WS2/ZrN soft/hard composite coating, a 0.9:0.1 thickness ratio of the above ingredients, and a total coating thickness of 0.5 μm.

关键词： Dry cutting performance Soft/hard composite-coated textured (SHCCT) tool Finite element analysis Coating parameters Cemented carbide

Preparation of Fe_2P/Al_2O_3 and FeP/Al_2O_3 catalysts for the hydrotreating reactions

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Journal of Energy Chemistry 2019年第2期28卷 116-121页

作者： Yamei Yuan Jiayou Zhang hui chen Qiumei Hou Jianyi Shen Laboratory of Mesoscopic Chemistry School of Chemistry and Chemical EngineeringNanjing University

A 60%Fe/Al_2O_3 catalyst was prepared by the co-precipitation *** was reduced by H_2 to produce metallic Fe,which was then sulfided by CS_2 to Fe_(0.96) S and Fe_3S_4 or phosphided by triphenylphosphine(PPh3) in liquid phases to Fe2 P and Fe *** was found that the iron sulfides(Fe0.96 S and Fe_3S_4) exhibited the low activity for the hydrodesulfurization(HDS) *** HDS activity was also low on the Fe(metal)/Al_2O_3 and Fe_2 P/Al_2O_3 catalysts since they were converted into Fe0.96 S and Fe_3S_4 during the HDS *** contrast,the FeP/Al_2O_3 was found to be stable and active for the HDS *** particular,Fe P/Al_2O_3 possessed significantly smaller Fe P particles than Fe P/C,leading to the significant higher HDS activity of FeP/Al_2O_3 than Fe P/C.

关键词： Fe2P/Al2O3 catalyst FeP/Al2O3 catalyst Liquid phase phosphidation PPh3 Hydrotreating reactions

Experimental investigation of thermal effect on cavitation characteristics in a liquid rocket engine turbopump inducer

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Chinese Journal of Aeronautics 2021年第8期34卷 48-57页

作者： Chunmin WANG Le XIANG Yonghua TAN hui chen Kaifu XU Northwestern Polytechnical University Xi'an 710072China Xi’an Aerospace Propulsion Institute Xi'an 710100China Academy of Aerospace Propulsion Technology Xi'an 710100China

The objective of this paper is to investigate the effect of water temperature on cavitation characteristics in a turbopump inducer,a series of experiments at different temperatures have been conducted in a newly developed visualization test *** is found that higher temperature shows little influence on the non-cavitation performance and breakdown characteristic in the investigated *** relationship between cavitation development and pressure fluctuation has been discussed in *** temperature displays a remarkable stabilization effect on the cavitation excited *** particular,the inception cavitation numbers of both the super-synchronous rotating cavitation and synchronous rotating cavitation are decreased at higher temperatures,and the corresponding frequencies are not affected,while the amplitudes are distinctly reduced,and the occurrence range of synchronous rotating cavitation is significantly narrowed.A generalized RayleighPlesset equation has been employed to account for the thermal effect on the bubble development,which may provide a deep insight in understanding the experimental *** effect is found to act as a remarkable dissipation mechanism to suppress the bubble growth,smooth the *** particular,the excited pressure during collapse is smaller at higher temperatures,which may lead to the stabilization effect of high temperature in this study.

关键词： Bubble dynamic Cavitation instability Inducer Thermal effect Visualization experiment

Energy efficiency maximization for buffer-aided multi-UAV relaying communications

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Journal of Systems Engineering and Electronics 2022年第2期33卷 312-321页

作者： CAO Dongju YANG Wendong chen hui WU Yang TANG Xuanxuan College of Communications Engineering Army Engineering University of PLANanjing 210007China Radar Non-commissioned Officer School Air Force Early Warning AcademyWuhan 430019China

This paper studies a multiple unmanned aerial vehicle(UAV)relaying communication system,where multiple UAV re-lays assist the blocked communication between a group of ground users(GUs)and a base station(BS).Since the UAVs only have limited-energy in practice,our design aims to maximize the energy efficiency(EE)through jointly designing the communica-tion scheduling,the transmit power allocation,as well as UAV trajectory under the buffer constraint over a given flight ***,the formulated fractional optimization problem is diffi-cult to be solved in general because of *** re-solve this difficulty,an efficient iterative algorithm is proposed based on the block coordinate descent(BCD)and successive convex approximation(SCA)techniques,as well as the Dinkel-bach’s ***,the optimization variables of the formulated problem are divided into three blocks and we alter-nately optimize each block of the variables over ***-cal results verify the convergence of the proposed iterative al-gorithm and show that the proposed designs achieve significant EE gain,which outperform other benchmark schemes.

关键词： unmanned aerial vehicle(UAV)relay buffer aided communication scheduling transmit power allocation UAV tra-jectory energy efficiency(EE)

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达卡巴嗪分子拉曼和紫外吸收光谱的理论研究

原子与分子物理学报 2025年第1期42卷 49-53页

作者：陈玉锋陈慧任黎英赵宁韩金玲李雨桐牡丹江师范学院化学化工学院黑龙江省光电功能材料重点实验室牡丹江157011

采用密度泛函理论(Density functionol theory,DFT),在B3LYP/6-31+g(d,p)基组水平上,对达卡巴嗪进行了结构优化,通过频率计算,获得达卡巴嗪的拉曼光谱,与实验获得的拉曼光谱进行对比,对400~2000 cm^(-1)频率范围内的拉曼光谱特征峰进行... 详细信息

采用密度泛函理论(Density functionol theory,DFT),在B3LYP/6-31+g(d,p)基组水平上,对达卡巴嗪进行了结构优化,通过频率计算,获得达卡巴嗪的拉曼光谱,与实验获得的拉曼光谱进行对比,对400~2000 cm^(-1)频率范围内的拉曼光谱特征峰进行了指认归属.计算分析前线分子轨道和表面静电势,预测了达卡巴嗪分子化学反应发生的位点.采用含时密度泛函理论(Time-dependent density functional theory,TDDFT)计算了该分子的紫外吸收光谱和激发态,获得电荷转移光谱,分析了达卡巴嗪分子间的电荷转移关系.

关键词：密度泛函理论达卡巴嗪拉曼光谱紫外光谱

Metadynamic recrystallization and microstructure evolution of a continuously cast Ti-microalloyed steel slab with heavy reduction

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Journal of Iron and Steel Research International 2022年第1期29卷 103-114页

作者： Zi-jian Wei cheng Ji Tian-ci chen Miao-yong Zhu chen-hui Wu Key Laboratory for Ecological Metallurgy of Multimetallic Ores(Ministry of Education) Shenyang 110819LiaoningChina School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina Pangang Group Research Institute Co. Ltd.Panzhihua 617000SichuanChina

The effects of the deformation parameters in the heavy reduction(HR)process on recrystallization kinetics and microstructure evolution were *** on the experimental results,metadynamic recrystallization(MDRX)kinetic and austenite grain size models were established for a continuously cast slab during ***,the evolution of the quenched microstructure after MDRX was observed using electron backscatter *** relative frequency of very low-angle grain boundaries decreased from 58.8% to 52.1%,and the relative frequency of high-angle grain boundaries increased from 28.5% to 38.9%.Analyses revealed that the recovery was the main softening *** decrease in the total grain boundary length indicated that subgrain growth occurred with increasing inter-pass *** main texture evolved from a {001}texture to a{112}texture,and the texture strength remained unchanged.

关键词： Microalloyed steel Heavy reduction Metadynamic recrystallization Microstructure evolution Kinetic model

Effect of tungsten carbide particles on microstructure and mechanical properties of Cu alloy composite bit matrix

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Journal of Iron and Steel Research International 2024年第2期31卷 519-530页

作者： Ding-qian Dong Feng-yuan He Xin-hui chen hui Li Kai-hua Shi hui-wen Xiong Xin Xiang Li Zhang College of Mechanical Engineering Sichuan University of Science and EngineeringZigong643000SichuanChina State Key Laboratory of Powder Metallurgy Central South UniversityChangsha410083HunanChina Zigong Cemented Carbide Co. Ltd.Zigong643011SichuanChina Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science and EngineeringZigong643000SichuanChina

Copper alloy composite bit matrix was prepared by pressureless vacuum infiltration,using at least one of the three kinds of tungsten carbide particles,for example,irregular cast tungsten carbide,monocrystalline tungsten carbide and sintered reduced tungsten carbide *** effects of powder particle morphology,particle size and mass fraction of tungsten carbide on the microstructure and mechanical properties of copper alloy composite were investigated by means of scanning electron microscopy,X-ray diffraction and abrasive wear test in *** results show that tungsten carbide morphology and particle size have obvious effects on the mechanical properties of copper alloy *** tungsten carbide partially dissolved in the copper alloy binding phase,and layers of Cu_(0.3)W_(0.5)Ni_(0.1)Mn_(0.1)C phase with a thickness of around 8–15μm were formed on the edge of the cast tungsten *** 45%irregular crushed fine cast tungsten carbide and 15%monocrystalline cast tungsten carbide were used as the skeleton,satisfactory comprehensive performance of the reinforced copper alloy composite bit matrix was obtained,with the bending strength,impact toughness and hardness reaching 1048 MPa,4.95 J/cm^(2) and 43.6 HRC,*** main wear mechanism was that the tungsten carbide particles firstly protruded from the friction surface after the copper alloy matrix was worn,and then peeled off from the matrix when further wear occurred.

关键词： Polycrystalline diamond compact Pressureless vacuum infiltration Copper alloy composite bit matrix Microstructure characterization Abrasive wear behavior