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Energy Efficiency Maximization in Mobile Edge Computing Networks via IRS assisted UAV communications

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Computer Modeling in Engineering & Sciences 2024年第2期138卷 1865-1884页

作者： Ying Zhang Weiming Niu Supu Xiu Guangchen Mu School of Electronic Information Engineering Henan Institute of TechnologyXinxiang453003China Houde College Henan Institute of TechnologyXinxiang453003China Department of Science Henan Institute of TechnologyXinxiang453003China

In this paper,we investigate the energy efficiency maximization for mobile edge computing(MEC)in intelligent reflecting surface(IRS)assisted unmanned aerial vehicle(UAV)*** particular,UAVcan collect the computing tasks of the terrestrial users and transmit the results back to them after *** jointly optimize the users’transmitted beamforming and uploading ratios,the phase shift matrix of IRS,and the UAV trajectory to improve the energy *** formulated optimization problem is highly non-convex and difficult to be solved ***,we decompose the original problem into three *** first propose the successive convex approximation(SCA)based method to design the beamforming of the users and the phase shift matrix of IRS,and apply the Lagrange dual method to obtain a closed-form expression of the uploading *** the trajectory optimization,we propose a block coordinate descent(BCD)based method to obtain a local optimal ***,we propose the alternating optimization(AO)based overall algorithmand analyzed its complexity to be equivalent or lower than existing *** results show the superiority of the proposedmethod compared with existing schemes in energy efficiency.

关键词： Mobile edge computing(MEC) unmanned aerial vehicle(UAV) intelligent reflecting surface(IRS) energy efficiency

design and Development of Garment Fabric Database Management System

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Journal of Donghua University(English Edition) 2022年第4期39卷 392-399页

作者： DU Jianxia LIU Zhengdong GENG Zengmin School of fashion Beijing Institute of Fashion TechnologyBeijing 100029China School of Arts and Sciences Beijing Institute of Fashion TechnologyBeijing 100029China

The main performance characteristics of garment fabric are analyzed and extracted,which include physical characteristics,appearance characteristics and subjective evaluation characteristics.A calculating model of fabric’s subjective evaluation is provided,which can be adjusted as the data *** database system of garment fabric is analyzed,and then function design,concept design and logic design are carried *** user interface(UI)design of garment fabric database system is *** system can not only serve the fabric management and customization of garment enterprises,but also serve the teaching work of colleges and universities,because it is rich in information and *** is of great significance to digital construction in the clothing field.

关键词： fabric physical characteristic subjective evaluation model of fabric fabric database design concept design logic design

Probabilistic Assessment of Wave Overtopping of Nampo Dikein the West Coast of Korea

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China Ocean Engineering 2008年第3期22卷 409-420页

作者：郄禄文崔秉昊谢世楞 College of Civil Engineering Hebei University Department of Civil and Environmental Engineering Sungkyunkwan University China communications First design institute of Navigation Engineering

The Nampo dike, which is located at the west coast of Korea, was destroyed by wave overtopping during the storms on 30 August and 17 September in 1959. In this paper, is performed the probabilistic assessment of wave overtopping of Nampo dike by use of Owen model, Van der Meer ＆ Janssen model and Hedges ＆ Reis model for wave overtopping of seawall. Based on the available tidal and wave data for storm surges in 1989, the risk assessment of wave overtopping of the Nampo dike has been carried out by both Level Ⅱ and Level Ⅲ reliability methods. The calculated resuhs show the general agreement of failure probability between the two methods. By utilizing the rehabilitated cross section of Nampo dike, the failure probability of wave overtopping for the Nampo dike after rehabilitation will be rapidly reduced to that of initial design at crest level of 9.0 m with the improved slope from 1 ： 2 to 1 ： 4 at seaside. Since the sea level may only rise 1.0 m in the next few decades, the failure probability of Nampo dike will be still in the safe range.

关键词： coastal structure dike wave overtopping failure probability probabilistic assessment

Study on Performance and Processability of Sirofil Lightweight Worsted Fabric

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Journal of Donghua University(English Edition) 2001年第2期18卷 10-13页

作者：李明菊范德忻葛惠萍侯祖龄 fashion institute Dong Hua University Shanghai 200051

The lightweight worsted fabric made of Sirofil yarn was developed and its textile performance was studied. By means of conventional testing, KES and FAST, it is concluded that with the coordination of proper fabric design and processing technique, the performance of this innovative fabric is superior to that of the conventional lightweight fabric Furthermore, it is predicted from the relevant parameters that its processability in the following suit manufacture is very desirable.

关键词： Lightweight Worsted Fabric, Sirofil yarn, Textile Performance, Proccessability , KES, FAST

Ancient mitochondrial genome depicts sheep maternal dispersal and migration in Eastern Asia

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Journal of Genetics and Genomics 2024年第1期51卷 87-95页

作者： Liu Yang Xing Zhang Yaning Hu Piao Zhu Hua Li Zhenyu Peng Hai Xiang Xinying Zhou Xingbo Zhao National Engineering Laboratory for Animal Breeding Key Laboratory of AnimalGeneticsBreeding and ReproductionMinistry of Agriculture and Rural AffairsCollege of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193China Guangdong Provincial Key Laboratory of Animal Molecular design and Precise Breeding School of Life Science and EngineeringFoshan UniversityFoshanGuangdong 528225China State Key Laboratory of Agricultural Genomics BGI-ShenzhenShenzhenGuangdong 518083China Key Laboratory of Vertebrate Evolution and Human Origins Institute of Vertebrate Paleontology and PaleoanthropologyChinese Academy of SciencesBeijing 100044China

Sheep have been one of the most important groups of animals since ancient ***,the knowledge of their migration routes and genetic relationships is still poorly *** investigate sheep maternal migration histories alongside Eurasian communications routes,in this study,we obtain mitochondrial genomes(mitogenomes)from 17 sheep remains in 6 Chinese sites and 1 Uzbekistan site dated 4429–3100 years before present(BP).By obtaining the mitogenomes from the sheep(4429–3556 BP)found in the Tongtian Cave site in Xinjiang,Altai region of northwest China,our results support the emergence of haplogroup C sheep in Xinjiang as early as 4429–3556 *** combined phylogenetic analyses with extant ancient and modern sheep mitogenomes suggest that the Uzbekistan-Altai region may have been a migration hub for early sheep in eastern *** least two migration events have taken place for sheep crossing Eurasia to China,one passing by Uzbekistan and Northwest China to the middle and lower reaches of the Yellow River at approximately 4000 BP and another following the Altai region to middle Inner Mongolia from 4429 BP to 2500 ***,this study provides further evidence for early sheep utilization and migration patterns in Eastern Asia.

关键词： Sheep Ancient DNA Eastern Asia Mitochondrial genome Migration Altai

Performance Analysis of Multilayer Coil Based MI Waveguide Communication System

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Computers, Materials & Continua 2022年第9期72卷 5287-5300页

作者： Sandeep N.Dandu Vinay Kumar Joydeep Sengupta Neeraj D.Bokde Department of Electronics and communications Engineering Visvesvaraya National Institute of TechnologyNagpur440010India Department of Electronics and communications Engineering Motilal Nehru National Institute of TechnologyPrayagraj211002India Department of Civil and Architectural Engineering-design and Construction 8000AarhusDenmark

In the non-conventional media like underwater and underground,the Radio Frequency(RF)communication technique does not perform well due to large antenna size requirement and high path *** such media,magnetic induction(MI)communication technique is very promising due to small coil size and constant channel *** the RF technique,the communication range in MI technique is relatively *** enhance this range,a waveguide technique is already brought in *** technique employs single layer coils to enhance the performance of MI *** further enhance the system functioning,in this paper,we investigated the performance of multi-layer coil(MLC)antenna based MI waveguide communication system in terms of transmission range,path loss,bit error rate(BER)and ***,the system performance is quantitatively evaluated in three different non-conventional media viz.,dry soil,fresh water and wet *** compared with the single layer counterpart,the MLC system shows a significant improvement in transmission range,BER even in loosely coupled scenarios and shows a corresponding reduction in path ***,the bandwidth is observed to be low(<1 KHz).In this analysis,the eddy current effects and parasitic capacitance are compared for single and multilayer *** is observed that the proposed system performs better in dry soil medium due to less medium conductivity.

关键词： Communication magnetic induction multilayer coil waveguide system

Hybrid Simulation of the Initiation and Runout Characteristics of a Catastrophic Debris Flow

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Journal of Mountain Science 2013年第2期10卷 219-232页

作者： CHEN Hong-Xin ZHANG Li-Min ZHANG Shuai XIANG Bo WANG Xiao-Feng Department of Civil and Environmental Engineering The Hong Kong University of Science and Technology Highway Planning SurveyDesign and Research InstituteSichuan Province Communications Department

On 13 August 2010, a catastrophic debris flow with a volume of 1.17 million m3 occurred in Xiaojiagou Ravine near Yingxiu town of Wenchuan county in Sichuan Province, China. The main source material was the landslide deposits retained in the ravine during the 2008 Wenchuan earthquake. This paper describes a two-dimensional hybrid numerical method that simulates the entire process of the debris flow from initiation to transportation and finally to deposition. The study area is discretized into a grid of square zones. A two dimensional finite difference method is then applied to simulate the rainfall-runoff and debris flow runout processes. The analysis is divided into three steps; namely, rainfall-runoff simulation, mixing water and solid materials, and debris flow runout simulation. The rainfall-runoff simulation is firstly conducted to obtain the cumulative runoff near the location of main source material and at the outlet of the first branch. The water and solid materials are then mixed to create an inflow hydrograph for the debris flow runout simulation. The occurrence time and volume of the debris flow can be estimated in this step. Finally the runout process of the debris flow is simulated. When the yield stress is high, it controls the deposition zone. When the yield stress is medium or low, both yield stress and viscosity influence the deposition zone. The flow velocity is largely influenced by the viscosity. The estimated yield stress by the equation, ty = pghsinO, and the estimated viscosity by the equation established by Bisantino et al. （2010） provide good estimates of the area of the debris flow fan and the distribution of deposition depth.

关键词： Debris flow Landslide Rain-inducedlandslide Surface runoff Runout distance Wenchuan earthquake Numerical simulation

THE EFFECT OF WAVE GROUPINESS ON A MOORED SHIP STUDIED BY NUMERICAL SIMULATIONS

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Journal of Hydrodynamics 2011年第2期23卷 145-153页

作者： MA Xiao-jian SUN Zhao-chen ZHANG Zhi-ming YANG Guo-ping ZHOU Feng State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China China communications Planning and design institute for Water Transportation Beijing 100007 China

Waves with the same wave parameters, such as significant wave height and period, but with different wave groupiness factors are simulated, to study the motion behavior of a moored ship under the action of waves with different Groupiness Factors of Height （GFH） and Group Length Factors （GLF）. The numerical results show that both the sway and heave motions increase with an increase in GFH. In contrast, the influence of GLF on the motions of a moored ship is weak.

关键词： wave groupiness moored ship Groupiness Factors of Height (GFH) Group Length Factors (GLF)

Large margin classification for combatingdisguise attacks on spam filters

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第3期13卷 187-195页

作者： Xi-chuan ZHOU Hai-bin SHEN Zhi-yong HUANG Guo-jun LI College of communications Engineering Chongqing UniversityChongqing40044China institute of VLSI design Zhejiang UniversityHangzhou 310027China Chongqing Communication institute Chongqing 400032China

This paper addresses the challenge of large margin classification for spare filtering in the presence of an adversary who disguises the spam mails to avoid being detected. In practice, the adversary may strategically add good words indicative of a legitimate message or remove bad words indicative of spam. We assume that the adversary could afford to modify a spam message only to a certain extent, without damaging its utility for the spammer. Under this assumption, we present a large margin approach for classification of spare messages that may be disguised. The proposed classifier is formulated as a second-order cone programming optimization. We performed a group of experiments using the TREC 2006 Spam Corpus. Results showed that the performance of the standard support vector machine （SVM） degrades rapidly when more words are injected or removed by the adversary, while the proposed approach is more stable under the disguise attack.

关键词： Large margin Spam filtering Second-order cone programming (SOCP) Adversarial classification