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Modeling and performance evaluation of the sleep mode in the IEEE 802.16e wireless networks with self-similar traffic

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The Journal of China Universities of Posts and Telecommunications 2009年第4期16卷 34-41页

作者： HUO Zhan-qiang jin shun-fu TIAN Nai-shuo wang Yan College of Information Science and Engineering Yanshan University Qinhuangdao 066004 China College of Science Yanshan University Qinhuangdao 066004 China School of Computer Science and Engineering Hebei University of Technology Tianjin 300401 China

IEEE 802.16e is currently the latest broadband wireless access standard designed to support mobility. In mobile networks, how to control energy consumption is one of the most important issues for battery-powered mobile stations. The standard proposes an energy saving mechanism named ＇sleep mode＇ for conserving the power of mobile stations. According to the operation principle of the sleep mode for downlink traffic in the type I power saving class, considering the self-similar nature of massive multimedia data in wireless networks, a discrete-time batch arrival Geom^x/G/1 queuing model with a close-down time and multiple vacations is built. The batch size is supposed to be Pareto distributed. By employing an embedded Markov chain method, the average queue length and the average sojourn time of the system model are derived. Correspondingly, the performance measures are obtained of the energy saving rate and the average packet delay time for the sleep mode in the IEEE 802.16e. The numerical results demonstrate the dependency relationships between the system performance measures and the system parameters with different offered loads and different self-similar degrees. Furthermore, a cost model is developed to determine the optimum length of the close-down time for minimizing the total system cost.

关键词： IEEE 802.16e sleep mode close-down self-similar energy saving rate

Substance P promotes epidural fibrosis via induction of type 2 macrophages

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Neural Regeneration Research 2023年第10期18卷 2252-2259页

作者： Feng Hua Hao-Ran wang Yun-Feng Bai jin-Peng Sun Wei-shun wang Ying Xu Ming-shun Zhang Jun Liu Department of Orthopedics The Second Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu ProvinceChina Department of Orthopedics Sir Run Run HospitalNanjing Medical UniversityNanjingJiangsu ProvinceChina Department of Intensive Care Unit Nanjing Drum Tower Hospitalthe Affiliated Hospital of Nanjing Medical UniversityNanjingJiangsu ProvinceChina NHC Key Laboratory of Antibody Technique Jiangsu Province Engineering Research Center of Antibody DrugDepartment of ImmunologyNanjing Medical UniversityNanjingJiangsu ProvinceChina

In response to spinal surgery,neurons secrete a large amount of substance P into the epidural *** P is involved in macrophage differentiation and fibrotic ***,the specific roles and mechanisms of substance P in epidural fibrosis remain *** this study,we established a mouse model of L1–L3 laminectomy and found that dorsal root ganglion neurons and the macrophages infiltrating into the wound area released *** vitro experiments revealed that type 1 macrophages secreted substance P,which promoted differentiation of type 1 macrophages towards a type 2 ***-throughput mRNA-seq analysis revealed that the sphingolipid metabolic pathway may be involved in the regulation of type 2 macrophages by substance ***,sphingomyelin synthase 2,a component of the sphingolipid metabolic pathway,promoted M2 differentiation in substance P-treated macrophages,while treating the macrophages with LY93,a sphingomyelin synthase 2 inhibitor,suppressed M2 *** addition,substance P promoted the formation of neutrophil extracellular traps,which further boosted M2 *** substance P with the neurokinin receptor 1 inhibitor RP67580 decreased the number of M2 macrophages in the wound area after spinal surgery and alleviated epidural fibrosis,as evidenced by decreased fibronectin,α-smooth muscle actin,and collagen I in the scar *** results demonstrated that substance P promotes M2 macrophage differentiation in epidural fibrosis via sphingomyelin synthase 2 and neutrophil extracellular *** findings provide a novel strategy for the treatment of epidural fibrosis.

关键词： dorsal root ganglion epidural fibrosis laminectomy macrophage mitochondria neurokinin receptor 1 neutrophil extracellular traps sphingomyelin synthase 2 substance P

Effect of heat treatment on corrosion behaviors of Mg-6Gd-3Y-0.5Zr alloy

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China Foundry 2024年第5期21卷 599-612页

作者： Fei wang Bin-guo Fu Yu-feng wang Tian-shun Dong Guo-lu Li jin-hai Liu Hebei Key Laboratory of New Functional Materials School of Materials Science and EngineeringHebei University of TechnologyTianjin 300401China Tianjin Institute of Aerospace Mechanical and Electrical Equipment Tianjin 300301China Tianjin Aerospace Long March Technology and Equipment Co. Ltd.Tianjin 300462China

The microstructures and corrosion behaviors of as-cast,T4-treated,and T6-treated Mg-6Gd-3Y-0.5Zr alloys were systematically investigated by SEM,TEM,immersion test,and electrochemical corrosion *** results show that the microstructure of the as-cast alloy is composed ofα-Mg and Mg_(24)(Gd,Y)_(5) eutectic phase,and in T4-treated alloy,Mg_(24)(Gd,Y)_(5) phase dissolves into theα-Mg matrix,leading to an increase in the(Y,Gd)H_(2) *** T6 treatment,nanoscale Mg_(24)(Gd,Y)_(5) phase dispersedly precipitates from theα-Mg matrix,and exhibits a specific orientation relationship with the α-Mg:(332)Mg_((24)(Gd,Y)_(5))//(1011)_(α-Mg),[136]Mg_((24)(Gd,Y)_(5))//[1210]_(α-Mg).The corrosion resistance of the Mg-6Gd-3Y-0.5Zr alloys can be ranked in the following order:T6-treated alloy exhibits the highest corrosion resistance,followed by the T4-treated alloy,and finally,the as-cast *** corrosion products of the alloys are all composed of MgO,Mg(OH)_(2),Gd_(2)O_(3),Y_(2)O_(3),and MgCl_(2).The corrosion behavior of Mg-6Gd-3Y-0.5Zr alloy is closely related to the precipitated *** establishing the relationship between corrosion rate,hydrogen evolution rate,and corrosion potential,it is further demonstrated that during the micro galvanic corrosion process,the coarse Mg_(24)(Gd,Y)_(5)phase in the as-cast alloy undergoes extensive dissolution,and(Y,Gd)H_(2) phase promotes the dissolution of theα-Mg matrix in the T4-treated alloy,intensifying the hydrogen evolution *** T6-treated alloy,with dispersive precipitation of nanoscale Mg_(24)(Gd,Y)_(5) phase,exhibits better corrosion resistance performance.

关键词： Mg-6Gd-3Y-0.5Zr alloy heat treatment microstructure precipitated phase corrosion resistance

Real-time K-TIG welding penetration prediction on embedded system using a segmentation-LSTM model

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Advances in Manufacturing 2023年第3期11卷 444-461页

作者： Yong-Hua Shi Zi-shun wang Xi-Yin Chen Yan-Xin Cui Tao Xu jin-Yi wang School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510006People's Republicof China

Keyhole tungsten inert gas(K-TIG)welding is capable of realizing single-sided welding and double-sided forming and has been widely used in medium and thick plate *** order to improve the accuracy of automatic weld identification and weld penetration prediction of robot in the process of large workpiece welding,a two-stage model is proposed in this paper,which can monitor the K-TIG welding penetration state in real time on the embedded system,called segmentation-LSTM *** proposed system extracts 9 weld pool geometric features with segmentation network,and then extracts the weld gap using a traditional *** these 10-dimensional features are input into the LSTM model to predict the penetration state,including under penetration,partial penetration,good penetration and over *** recognition accuracy of the proposed system can reach 95.2%.In this system,to solve the difficulty of labeling data and lack of segmentation accuracy,an improved LabelMe capable of live-wire annotation tool and a novel loss function were proposed,*** latter was also called focal dice loss,which enabled the network to achieve a performance of 0.933 mloU on the testing ***,an improved slimming strategy compresses the network,making the segmentation network achieve real-time on the embedded system(RK3399pro).

关键词： Keyhole tungsten inert gas(K-TIG)welding Penetration state prediction Segmentation-LSTM model Embedded system Focal dice loss Improved LabelMe

传统模具与新型模具制作适形铅挡块的比较分析

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江西医学院学报 2009年第10期49卷 99-101,F0003页

作者：赵毅辉艾春红罗晓东王顺金南昌大学研究生院医学部 2007级南昌330006 南昌大学第二附属医院肿瘤科南昌330006

目的探讨传统模具与新型模具制作适形铅挡块的误差。方法根据治疗计划系统生成的照射野文件,分别采用传统模具与新型模具制作适形铅挡块,并测量各自的误差。结果传统模具与新型模具制作的适形铅挡块误差差异无统计学意义(P=0.9767)。结... 详细信息

目的探讨传统模具与新型模具制作适形铅挡块的误差。方法根据治疗计划系统生成的照射野文件,分别采用传统模具与新型模具制作适形铅挡块,并测量各自的误差。结果传统模具与新型模具制作的适形铅挡块误差差异无统计学意义(P=0.9767)。结论新型模具与传统模具制成的适形铅挡块无明显误差。新型模具是一种节省材料、精确度好、速度快、操作简单的一种制模工具,能替代传统模具。

关键词：适形铅挡块传统模具新型模具

生成坐标方法与原子核集体运动Ⅷ集体自由度的选定及其表示

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高能物理与核物理 1987年第3期 384-391页

作者：徐躬耦王顺金杨亚天李福利兰州大学

本文具体地从一个理想模型讨论了集体运动自由度的选定及其表示问题.从它的动力学群出发,指出虽然可以有不同的连续变量或玻色子表示,但是,独立集体自由度的数目是唯一地确定了的.如果涉及超过这个数目的集体自由度,则必有伴随的条件.

关键词：不可约表示核物理原子核集体运动群表示生成坐标方法稳定子群动力学对称性玻色子核子重子费密子原子分子哈密顿量高能物理

Highly selective and efficient electroreduction of CO_(2) in water by quaterpyridine derivative‐based molecular catalyst noncovalently tethered to carbon nanotubes

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SmartMat 2022年第1期3卷 151-162页

作者： Vikas Reddu Libo Sun Xiaogang Li Huile jin shun wang Xin wang School of Chemical and Biomedical Engineering Nanyang Technological UniversitySingaporeSingapore Cambridge Centre for Advanced Research and Education in Singapore Ltd(Cambridge CARES) CREATE TowerSingaporeSingapore College of Chemistry&Materials Engineering Wenzhou UniversityWenzhouChina

A disubstituted quaterpyridine based cobalt complex non‐covalently tethered to multiwalled carbon nanotube(MWCNT)substrate,forming a hybrid catalyst,Co‐qpyCOOH/CNT,catalyzed the conversion of CO_(2) to CO under aqueous *** an optimal and uniform loading,it exhibited remarkable catalytic activity,near‐exclusive selectivity,and high stability towards the formation of *** a mere cathodic potential of−0.65 V versus RHE(η=0.54 V),it achieved a high partial current density of−6.7 mA/cm^(2) and a ***=100%.In addition,with 20 h of stable operation,hydrogen evolution remained practically *** hybrid structure due to noncovalent immobilization on MWCNT imparted the intrinsic activity and much‐needed stability in performance whereas‒COOH groups may stabilize the intermediates by acting as H‐bond donors,promoting catalytic *** to a conductive solid substrate and tuning of the second sphere of coordination played an important role in its performance to achieve desired reduction product with high selectivity and activity.

关键词： carbon dioxide reduction cobalt complex disubstituted quaterpyridine heterogeneous molecular catalysis second coordination sphere

Variations of extreme temperature in the Mount Qomolangma region in China during 1971-2020

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Journal of Mountain Science 2023年第12期20卷 3488-3499页

作者： wang shun-jiu Sichuan Provincial Climate Centre Chengdu 610072China Institute of Plateau Meteorological China Meteorological AdministrationChengdu 610072China Heavy Rain and Drought-Flood Disasters in Plateau and Basin Key Laboratory of Sichuan Province Chengdu 610072China

According to observational daily temperature data from the meteorological stations during 1971-2020,the variations of the extreme temperature event in the Mount Qomolangma(also known as Mount Everest) region in China have been analyzed using statistical *** extreme temperature indices recommended by the World Meteorological Organization are selected to describe the extreme temperature *** RClimDEX 1.0 software is used to calculate the extreme temperature *** are no tropical nights,and just three summer days at the last 50 *** frost days are the main extreme temperature events all year *** temperature in the north slope is more extreme than that in the south slope of the Mount *** is remarkable decadal variation for the extreme temperature indices except diurnal temperature *** are the warm extremes increasing,however,the cold extremes decreasing with the decadal lapse,which is more remarkable into the 21^(th) *** tendencies for the extreme temperature indices in the north slope are consistent with those in the south *** are statistically significant trends for most extreme temperature indices during the study *** shows that the warm extremes would be more prominent in the future with the global continued *** abrupt changes of the extreme temperature index have occurred mainly in the 20^(th) century especially from the mid to late 1980s and *** periodic changes in the south slope do not synchronize those in the north slope for the most extreme temperature *** is different for most extreme temperature indices between the south and north slope,which has demonstrated that the regional or local changes are not neglectable for extreme temperature *** results of this study are also the consistent response of extreme temperature event to the global warming.

关键词： Extreme temperature Variation Trend Statistical analysis Mount Qomolangma Mount Everest

Method of temperature rising velocity and threshold control of electron beam brazing

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Journal of University of Science and Technology Beijing 2005年第5期12卷 440-444页

作者： Xuedong wang shun Yao Welding Institute Shanghai Jiaotong University Shanghai 200030 China

In order to accommodate electron beam to the brazing of the joints with various curve shapes and the brazing of thermo sensitive materials, the method of electron beam scanning and brazing temperature control was developed, in which electron beam was controlled to scan according to predefined scanning track, and the actual temperature rising velocity of the brazed seam was lim- ited in an allowed scope by detecting the brazed seam temperature, calculating the temperature rising velocity and adjusting the beam current during the brazing process; in addition, through the setting of the highest allowed temperature, the actual temperature of the brazed seam could be controlled not exceeding the threshold set value, and these two methods could be employed alone or jointly. It is shown that high precision temperature control in electron beam brazing could be realized and the productivity be increased by the proposed method.

关键词： electron beam brazing scanning track temperature rising velocity temperature threshold