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On the System Performance of Mobile Edge Computing in an Uplink NOma WSN With a Multiantenna Access Point Over Nakagami-m Fading

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IEEE/CAA Journal of Automatica Sinica 2022年第4期9卷 668-685页

作者： Van-Truong Truong Van Nhan Vo Dac-Binh ha Chakchai So-In the Faculty of Electrical-Electronic Engineering Duy Tan University the Institute of Research and Development Duy Tan University the Faculty of Information Technology Duy Tan University IEEE the Applied Network Technology(ANT)Laboratory Department of Computer ScienceCollege of ComputingKhon Kaen University

In this paper,we study the system performance of mobile edge computing(MEC)wireless sensor networks(WSNs)using a multiantenna access point(AP)and two sensor clusters based on uplink nonorthogonal multiple access(NOma).Due to limited computation and energy resources,the cluster heads(CHs)offload their tasks to a multiantenna AP over Nakagami-m *** proposed a combination protocol for NOma-MEC-WSNs in which the AP selects either selection combining(SC)or maximal ratio combining(MRC)and each cluster selects a CH to participate in the communication process by employing the sensor node(SN)*** derive the closed-form exact expressions of the successful computation probability(SCP)to evaluate the system performance with the latency and energy consumption constraints of the considered *** results are provided to gain insight into the system performance in terms of the SCP based on system parameters such as the number of AP antennas,number of SNs in each cluster,task length,working frequency,offloading ratio,and transmit power ***,to determine the optimal resource parameters,i.e.,the offloading ratio,power allocation of the two CHs,and MEC AP resources,we proposed two algorithms to achieve the best system *** approach reveals that the optimal parameters with different schemes significantly improve SCP compared to other similar *** use Monte Carlo simulations to confirm the validity of our analysis.

关键词： Mobile edge computing(MEC) Nakagami-m fading offloading selection combining(SC)/maximal ratio combining(MRC) successful computation probability(SCP) uplink nonortho-gonal multiple access(NOma) wireless sensor networks(WSNs)

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Effect of calcinations temperature on the luminescence intensity and fluorescent lifetime of Tb^(3+)-doped hydroxyapatite(Tb-ha)nanocrystallines

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Journal of materiomics 2017年第2期3卷 144-149页

作者： hairong Yin Yanxiao Li Jianguang Bai Mingxin ma Jing Liu School of materials Science&Engineering Shaanxi University of Science&TechnologyXi'an 710021China

Hydroxyapatite luminescent nanocrystallines doped with 6 mol.%Tb^(3+)(Tb-ha)were prepared via chemical deposition method and calcined at different temperature,and the effects of calcinations temperature on the luminescence intensity and fluorescent lifetime were *** image of Tb-ha revealed that the shape of nanocrystallines changed from needle-like to short rod-like and sphere-like with the increase of calcinations temperature;while the particles sizes decreased from 190 nm to 110 *** crystallinity degree *** typical emission peaks attributed to Tb^(3+) ions were observed in emission spectra of 6 mol.%Tb-ha under 378 nm *** luminescent intensity of Tb-ha,which showed the fluorescence quenching,firstly enhanced and then decreased at 700℃;while the fluorescent lifetime increased firstly and then decreased after 600℃.Furthermore,the ratio of intensity between 545 nm and 490 nm corresponding to electric-dipole and magnetic-dipole transition(I_(R):I_(O))increases firstly and then decreases,which revealed that the proportion of substitute type and site of Ca^(2+) ions by Tb^(3+) ions were helpful to realize the substitute process and functional structure design.

关键词： Tb-ha Tb^(3+) Calcinations temperature Luminescent intensity Fluorescent lifetime

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AlGaN Channel High Electron Mobility Transistors with Ultra-Low Drain-Induced-Barrier-Lowering Coefficient

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Chinese Physics Letters 2013年第12期30卷 123-125页

作者： ha Wei ZhaNG Jin-Cheng ZhaO Sheng-Lei GE Sha-Sha WEN Hui-Juan ZhaNG Chun-Fu ma Xiao-Hua haO Yue Key Laboratory of Wide Band Gap Semiconductor materials and Devices School of MicroelectronicsXidian UniversityXi'an 710071

The conventional AlGaN/GaN high electron mobility transistor(HEMT),the AlGaN/GaN/AlGaN HEMT,and the Al_(x)Ga_(1-x)N/Al_(y)Ga_(1-y)N HEMT are fabricated on sapphire substrates to study the drain-induced barrier-lowering(DIBL)*** is found that the Al_(x)Ga_(1-x)N/Al_(y)Ga_(1-y)N HEMT with AlGaN channel has the lowest DIBL coefficient of 6.7 mV/V compared with the other two *** is attributed to the best two-dimensional electron gas confinement of the Al_(x)Ga_(1-x)N/Al_(y)Ga_(1-y)N *** opinion is further confirmed by the conduction band diagrams and electron distribution calculated from the one-dimensional Poisson–Schrödinger equation.

关键词： AlGaN sapphire drain

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Observation and Numerical Simulations with Radar and Surface Data Assimilation for Heavy Rainfall over Central Korea

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Advances in Atmospheric Sciences 2011年第3期28卷 573-590页

作者： Ji-Hyun ha Hyung-Woo KIM Dong-Kyou LEE Atmospheric Sciences Program School of Earth and Environmental SciencesSeoul National UniversitySeoul 151-747Korea

This study investigated the impact of multiple-Doppler radar data and surface data assimilation on forecasts of heavy rainfall over the central Korean Peninsula;the Weather Research and Forecasting(WRF) model and its three-dimensional variational data assimilation system(3DVAR) were used for this purpose. During data assimilation,the WRF 3DVAR cycling mode with incremental analysis updates(iaU) was used. A maximum rainfall of 335.0 mm occurred during a 12-h period from 2100 UTC 11 July 2006 to 0900 UTC 12 July *** radar data showed that the heavy rainfall was due to the back-building formation of mesoscale convective systems(MCSs).New convective cells were continuously formed in the upstream region,which was characterized by a strong southwesterly low-level jet(LLJ).The LLJ also facilitated strong convergence due to horizontal wind shear,which resulted in maintenance of the *** assimilation of both multiple-Doppler radar and surface data improved the accuracy of precipitation forecasts and had a more positive impact on quantitative forecasting(QPF) than the assimilation of either radar data or surface data *** back-building characteristic was successfully forecasted when the multiple-Doppler radar data and surface data were *** data assimilation experiments,the radar data helped forecast the development of convective storms responsible for heavy rainfall,and the surface data contributed to the occurrence of intensified low-level *** surface data played a significant role in enhancing the thermal gradient and modulating the planetary boundary layer of the model,which resulted in favorable conditions for convection.

关键词： radar and surface data data assimilation mesoscale convective system heavy rainfall

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Expression of E-cadherin and α-catenin in a varicocele-induced infertility rat model

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Asian Journal of Andrology 2011年第3期13卷 470-475,514页

作者： Hong Koo ha Hyun Jun Park Nam Cheol Park Department of Urology Pusan National University School of Medicine Busan 602739 Korea Medical Research Institute Pusan National University Hospital Busan 602739 Korea

The roles of E-cadherin and α-catenin were evaluated in the development of varicocele-induced infertility. Analysis of the association between the expression of E-cadherinla-catenin and clinical/pathological parameters was performed. Thirty lO-week-old male rats （experimental group） were used for the experiments; the left renal vein was ligated to form a varicocele. The abdomen was incised in 30 rats （control group） and no procedure was performed on 10 rats （baseline group）. The weights of the left testis, serum reactive oxygen species （ROS）, testosterone, luteinizing hormone （LH）, follicle-stimulating hormone （FSH） and degenerative changes in the seminiferous tubules after 4 and 8 weeks were recorded. The expression of E-cadherin and α-catenin was evaluated by immunohistochemical （IHC） staining and Western blot analysis. The ROS increased in the 8-week experimental group, compared with the baseline and control groups （P〈0.001 for both）. Additionally, FSH significantly increased in the 4- and 8-week experimental group compared with the control groups （P= 0.013 and P= 0.032, respectively）. The ratio of degenerative changes in the seminiferous tubules of the experimental groups increased. The IHC staining showed that the expression of E-cadherin and a-catenin decreased in the 4- and 8-week experimental groups. Similar to the IHC staining, the experimental group had decreased reactivity on Western blot analysis. The expression of E-cadherin and a-catenin was significantly associated with the ROS and degenerative changes in the seminiferous tubules. The results of this study suggest that damage to the blood-testis barrier （BTB） is associated with varicocele-induced male infertility, and that ROS may cause damage to the BTB.

关键词： α-catenin blood-testis barrier E-cadherin varicocele infertility

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基于乡村多功能评价的城市边缘区“三生”空间划分研究

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地理科学进展 2019年第9期38卷 1382-1392页

作者：马晓冬李鑫胡睿 KHUONG manh ha 江苏师范大学地理测绘与城乡规划学院江苏徐州221116 北江农林大学土地与资源环境学院越南北江0084240

城市边缘区乡村多元价值凸显,迫切需以乡村多功能理论为指导划分'三生'空间,以空间重构促进转型发展。论文首先从生产、生活与生态功能方面评价城市边缘区多功能时空变化;其次进行图斑尺度'三生'空间适宜性评价,两者共同得到基于乡村多... 详细信息

城市边缘区乡村多元价值凸显,迫切需以乡村多功能理论为指导划分'三生'空间,以空间重构促进转型发展。论文首先从生产、生活与生态功能方面评价城市边缘区多功能时空变化;其次进行图斑尺度'三生'空间适宜性评价,两者共同得到基于乡村多功能的'三生'空间适宜性;最后据此设计算法划分'三生'空间。研究发现:①城市边缘区乡村休闲娱乐、观光农业等功能显现,需要重构多功能空间促进转型发展;②江苏徐州市铜山区乡村非农生产与生活功能主要分布在与中心城区较近地区,农业空间主要分布在中心城区远郊外围,生态功能则表现出高度空间异质性,农业、非农生产与生活功能在提升,而生态功能则普遍下降;③县域'三生'空间划定需多尺度联合,既要考虑乡镇尺度多功能差异,还要体现图斑尺度适宜性,才能为空间规划提供有意义的借鉴。论文提出的基于乡村多功能评价的'三生'空间划分可为即将开展的国土空间规划提供科学依据。

关键词：乡村多功能城市边缘区 “三生”空间江苏徐州铜山区

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New tricyanoiron(Ⅲ) building blocks for the construction of molecule-based magnets

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Science China Chemistry 2010年第10期53卷 2106-2111页

作者： LAU Pui-ha WONG Wing-Tak LAU Tai-Chu Department of Biology and Chemistry City University of Hong Kong Department of Chemistry The University of Hong Kong

A series of tricyanoiron(Ⅲ) complexes with the general formula mer-[FeⅢ(5-Xsap)(CN)3]2-(X = H, Me, MeO, Cl or Br, sapH2 = N-salicylidene-o-aminophenol) have been synthesized. These complexes were characterized by IR, ESI-MS, UV/Vis, elemental analysis and magnetic measurements. The structures of (PPh4)2[FeⅢ(sap)(CN)3] and (PPh4)2[FeⅢ(5-Mesap)(CN)3] have been determined by X-ray crystallography. These low-spin d5 tricyanoiron(Ⅲ) complexes are potential building blocks for the construction of molecule-based magnets.

关键词： cyano iron Schiff base building block molecule-based magnet

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A TCP Performance Enhancement Scheme in Infrastructure based Vehicular Networks

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China Communications 2015年第6期12卷 73-84页

作者： ha Le FANG Lijin BI Yuanguo LIU Wei Northeastern University Shenyang Ligong University

Transmission Control Protocol （TCP） in infrastructure based vehicular net- works is dedicated to support reliable Intemet services for mobile users. However, an end-to- end TCP flow not only experiences some com- mon challenges in wireless mobile networks, such as high packet loss rate, medium access competition, unstable wireless bandwidth, and dynamic topology, etc., but also suffers from performance degradation due to traffic congestion at the Road-Side Units （RSUs） that connect the wireline and wireless networks. In order to address the challenging issues related to reliable TCP transmissions in infrastruc- ture based vehicular networks, we propose an RSU based TCP （R-TCP） scheme. For wireline source nodes, R-TCP adopts a novel flow control mechanism to adjust transmission rates according to the status of bottleneck link. Specifically, during the short wireless connec- tion time in Infrastructure based vehicular net- works, R-TCP quickly chooses an ideal trans- mission rate for data transmissions instead of activating the slow start algorithm after the connection is established, and successfully avoids the oscillation of the transmission rate. Simulation results show that R-TCP achieves great advantages than some relate proposals in terms of throughput, end-to-end delay, and packet loss rate.

关键词： rate control bottleneck node packet loss infrastructure based vehicular net-works

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A Comparison of GPS- and NWP-derived PW Data over the Korean Peninsula

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Advances in Atmospheric Sciences 2010年第4期27卷 871-882页

作者： ha-Taek KWON Eui-Hyun JUNG Gyu-Ho LIM School of Earth and Environmental Sciences Seoul National University Seoul 151-172 Korea

Precipitable Water （PW） derived from Global Positioning System （GPS） measurements and numerical weather prediction （NWP） model analysis data were compared to further evaluate the effcacy of applying GPS-derived PW to the NWP model. The spatial and temporal variations of GPS-derived PW during a rainfall event were also examined. GPS-derived PW measurements show good agreement with the behavior of water vapor at a high spatial resolution during the analysis period. Temporal anomalies of GPS-derived PW moving along with the front are successfully detected by the GPS array. Large positive anomalies of GPS-derived PW are indicated immediately before a rainfall event, and the intensity of these positive anomalies do not seem to decrease significantly as the precipitation system passes. These results indicate that the Korean GPS network may have great potential as a PW sensor over the Korean Peninsula. In contrast with GPS-derived PW, NWP-derived PW shows negative biases. These biases appear to stem mainly from the differences between modeled and actual GPS site elevations, as GPS sites were generally located at elevations lower than those employed by the NWP model. However, there still exists a discernable dry bias after a PW correction is applied to NWP-derived PW. GPS-derived PW better reflects the spatial and temporal moisture variations of precipitation systems, as compared to NWP-derived PW. These results provide entirely new information for improving the regional NWP system, since GPS-derived PW produced with data from the Korean GPS network may be incorporated into the NWP model to improve rainfall forecasts.

关键词： GPS precipitable water numerical weather prediction model dry bias

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Initial Rifting Age of the Nearly N–S Rifts in Southern Tibetan Plateau:New Evidence from the Age limit of the Early Sediments

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 739-740页

作者： ha Guanghao WU Zhonghai HE Lin WANG Shubing Institute of Geomechanics Chinese Academy of Geological SciencesBeijing 100081China Key Laboratory of Neotectonic Movement&Geohazard Ministry of Land and ResourcesBeijing 100081China Chinese Academy of Geological Sciences Beijing 100037China College of Earth Science and Resources China University of Geosciences(Beijing)Beijing 100083China

Objective The nearly parallel N-S-trending rifts in southern Tibet represent the E-W extension of the Tibet Plateau. Most data which constrained the age of the extensional deformation come from isotopic dating of the dikes probably related to the activity of the nearly N-S faulting and micas from hydrothermal activity and the low- temperature thermochronology of plateau uplift. Previous research shows that there are at least three different ideas about the age of the rifts：（1） older than 16-12 ma, （2） 14- 10 ma, and （3） 8-4 ma （Fig. la）. For the old sedimentary strata represented the beginning of the rifting, the dating of the sediments helps to better define the initial rifting age.

关键词： Initial Rifting Age of the Nearly N S Rifts in Southern Tibetan Plateau:New Evidence from the Age limit of the Early Sediments

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