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Compressive Sensing Approach in Multicarrier Sparsely Indexing Modulation Systems

China comm.nications 2017年第11期14卷 151-166页

作者： Mostafa Salah Osama A.Omer Usama S.Mohamed dept. of Electrical Engineering Sohag University Sohag Egypt dept. of Electrical Engineering Aswan University Aswan 81542 Egypt dept. of Electrical Engineering Assiut University Assiut Egypt dept. of Electronics & comm. Engineering Arab Academy for Science Technology and Maritime Transport Aswan

recently the indexed modulation(IM) technique in conjunction with the multi-carrier modulation gains an increasing attention. It conveys additional information on the subcarrier indices by activating specific subcarriers in the frequency domain besides the conventional amplitude-phase modulation of the activated subcarriers. Orthogonal frequency division multiplexing(OFDM) with IM(OFDM-IM) is deeply compared with the classical OFDM. It leads to an attractive trade-off between the spectral efficiency(SE) and the energy efficiency(EE). In this paper, the concept of the combinatorial modulation is introduced from a new point of view. The sparsity mapping is suggested intentionally to enable the compressive sensing(CS) concept in the data recovery process to provide further performance and EE enhancement without SE loss. Generating artificial data sparsity in the frequency domain along with naturally embedded channel sparsity in the time domain allows joint data recovery and channel estimation in a double sparsity framework. Based on simulation results, the performance of the proposed approach agrees with the predicted CS superiority even under low signal-to-noise ratio without channel coding. Moreover, the proposed sparsely indexed modulation system outperforms the conventional OFDM system and the OFDM-IM system in terms of error performance, peak-to-average power ratio(PAPR) and energy efficiency under the same spectral efficiency.

关键词： indexed modulation combinatorial modulation double sparsity critical sparsity sparsely indexed modulation OFDM-IM

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Perceptual importance analysis for H.264/AVC bit allocation

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第2期9卷 225-231页

作者： Gui-xu LIN Shi-bao ZHENG Institute of lmage comm. ＆ Info. Processing Dept. of Electronic Engineering Shanghai Jiao Tong University Shanghai 200240 China Shanghai Key Laboratory of Digital Media Processing and Transmissions Shanghai Jiao Tong University Shanghai 200240 China

The existing H.264/AVC rate control schemes rarely include the perceptual *** a result,the im-provements in visual quality are hardly comparable to those in peak signal-to-noise ratio(PSNR).In this paper,we propose a perceptual importance analysis scheme to accurately abstract the spatial and temporal perceptual characteristics of video *** we perform bit allocation at macroblock(MB)level by adopting a perceptual mode decision scheme,which adaptively updates the Lagrangian multiplier for mode decision according to the perceptual importance of each *** results show that the proposed scheme can efficiently reduce bit rates without visual quality degradation.

关键词： Visual quality Human visual system Rate control H.264/AVC

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QSM-IDM -A novel quadrature spatial modulation based on interleaving division multiplexing for multiple antenna system

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Digital comm.nications and Networks 2019年第3期5卷 183-188页

作者： Sherif K. El Dyasti Esam A.A. Hagras Hadia El-Hennawy Ain Shams Cairo Egypt Elec and Comm. Dept Technical Research Centre Cairo Egypt Faculty of Engineering Ain Shams Cairo Egypt

Quadrature Spatial Modulation (QSM) is a high spectral efficiency Multiple-Input Multiple Output (MIMO) technique used to improve the spectral efficiency of wireless comm.nication systems. The main concept of QSM is to extend the spatial constellation of the conventional Spatial Modulation (SM) in both the in-phase and quadrature components of the data symbol. In this paper, because QSM-based on Interleaxdng Division Multiplexing (IDM) has not been introduced in the literature as a multiple antenna system, we introduced a novel scheme, called QSM system based on Interleaving Division Multiplexing (QSM-IDM). The antenna sets are also applied to a spreader, before being used to assign an antenna number for information transmission. Analysis and simulations for a flat fading channel show that the proposed QSM-IDM method significantly outperforms the original QSM system with the same data rate, while maintaining a relatively acceptable complexity. The obtained simulation results show that the conducted analysis yields significant improvements for the accuracy of the proposed scheme, with satisfactory complexity.

关键词： Interleaver Division Multiplexing (IDM) Multiple Input Multiple Output (MIMO) Spatial Modulation (SM) Quadrature Spatial Modulation (QSM)

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A PARALLEL ALGORITHM FOR GENERATINGMULTIPLE ORDERING SPANNING TREESIN UNDIRECTED WEIGHTED GRAPHS

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Acta Mathematicae Applicatae Sinica 1999年第3期15卷 303-309页

作者：马军马绍汉岩间一雄顾谦平 Department of Computer Science Shandong University Jinan China dept. of Comput. Sci. & comm. Eng. Kyushu University Fukuoka City Japan dept. of Software Univ. of Aizu Tsuruga Aizu Wakamatsu City Fukushima Japan

In this paper, we propose an efficient parallel algorithm for generating k spanning trees of a connected, weighted and undirected graph Q(V,E,W) in the order of increasingweight. It runs in O(Tmst(n)+klogn) time with O(n2/ logn) processors on a CREW PRAM,where n=|V|, m=|E| and Tmst(n), O(log n)＜Tmst(n)＜O(log2 n) is the run time of the fastest parallel algorithm for finding a minimum spanning tree (MST) of G on a CREW PRAM. SinceTmst(n)=O(log2 n) for the time being, our algorithm is of the same time bound with Tmst(n)when k＜O(log n).

关键词： Parallel algorithms minimum spanning trees networks graph algorithms

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FER Performance in the IEEE 802.11 a/g/n Wireless LAN over Fading Channel

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comm.nications and Network 2013年第3期5卷 10-15页

作者： Ha Cheol Lee dept. of Information and comm. Eng. Yuhan University Bucheon City Korea

This paper explores and compares FER (Frame Error Rate) of a MAC (Medium Access Control) layer in the IEEE 802.11 a/g/n wireless LAN. It is evaluated under the fading wireless channel, using theoretical analysis method. It is analyzed by using the number of stations with both variable payload size and mobile speed on the condition that fading margin and transmission probability are fixed. Especially, in the IEEE 802.11n, A-MSDU (MAC Service Data Unit Aggregation) scheme is considered and the number of subframe is used as the variable parameter. In the IEEE802.11a/g wireless LAN, fixed wireless channel is assumed to be Rayleigh fading channel. Mobile wireless channel is assumed to be flat fading Rayleigh channel with Jake spectrum. The channel is in fading states or inter-fading states by evaluating a certain threshold value of received signal power level. If and only if the whole frame is in inter-fading state, there is the successful frame transmission. If any part of frame is in fading duration, the frame is received in error.

关键词： Wireless LAN MAC FER IEEE 802.11a/g/n

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EFFICIENT IMAGE SEGMENTATION FOR SEMANTIC OBJECT GENERATION

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Journal of Electronics(China) 2002年第4期19卷 420-425页

作者： Chen Xiaotang Yu Yinglin (dept. of comm. & Info. Eng., South China Univ. of Technology, Guangzhou 510640) dept. of comm. & Info. Eng. South China Univ. of Technology Guangzhou 510640

This letter presents an efficient and simple image segmentation method for semantic object spatial segmentation. First, the image is filtered using contour-preserving filters. Then it is quasi-flat labeled. The small regions near the contour are classified as uncertain regions and are eliminated by region growing and merging. Further region merging is used to reduce the region number. The simulation results show its efficiency and simplicity. It can preserve the semantic object shape while emphasize on the perceptual complex part of the object. So it conforms to the human visual perception very well.

关键词： Image segmentation Semantic object Contour-preserving noise filtering Quasi-flat regions labeling Region merging

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Determination of Conversion Coefficient to Evaluate Couple-year of Protection (CYP) for Tubectomy and Vasectomy in Urban and Rural Regions of Iran:IMES Study

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Journal of Reproduction and Contraception 2009年第2期20卷 81-92页

作者： Farzane Alinejad Abtin Heidarzade Mohammad Eslami Roya Faraji Mohsen Shatti Shervin Ghadarjani Faculty of medicine Guilan University of Medical Sciences dept. of comm.nity medicine Faculty of Medicine Guilan University of Medical Sciences family Planning Office Family Health Department Ministry of Health Central Building dept. of Obstetrics and GYN Guilan University of Medical Sciences Monitoring and Evaluation Office Family Health Section Ministry of Health and Medical Education

Objective To calculate couple-year of protection （CYP） by conversion coefficient （F） of tubectomy and vasectomy in urban and rural regions of Iran. Methods A total of 103 450 married women aged 10-49 years in 2005 across urban and rural regions of lran were sampled by multi stage cluster sampling. The data were collected by household survey and direct interview and analyzed by STATA8.0 software and survey analysis comm.nds. Results Mean age of the women at the time of tubectomy estimated 31.9 years and conversion coefficient of tubectomy was 17.1 ±0.1. Mean age of women at the time of her husband vasectomy estimated 31.48 years and its conversion coefficient was 17. 5 ± 0. 1. Cluster analysis defined different regions of Iran on the basis of evaluated conversion coefficients of tubectomy and vasectomy which both of them presented seven clusters. Literacy of women and total coverage of family planning in a region had a direct relationship with this conversion coefficient （P〈0.05）. Conclusion The variations observed in the conversion coefficients and their dissimilarity among different regions of Iran may be due to a variety of fundamental factors of which literacy and culture are of important factors.

关键词： family planning contraception vasectomy tubectomy conversion coefficient (F) couple-year of protection (CYP)

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SYNTHESIS OF NOVEL HYDROPHILIC BIODEGRADABLE POLYESTER WITH FUNCTIONALIZED SIDE CHAIN GROUPS

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Chinese Journal of Polymer Science 2001年第5期19卷 509-516页

作者： Ji-yuan Yang Jian Yu Huai-zhong Pan Zhong-wei Gu Wei-xiao Cao Xin-de Feng Department of Polymer Science and Engineering Peking University Beijing 100871, China National Research Institute for family Planning Beijing 100081, China dept. of Poly. Sci. and Engineering Peking University Beijing 100871 China Natl. Res. Inst. for family Planning Beijing 100081 China

A substituted glycolide, 3-benzyloxymethyl-1,4-dioxane-2,5-dione, was synthesized. It is a suitable precursor for the preparation of a new hydrophilic biodegradable poly(a-hydroxy acid). The polymerizations were carried out in bulk in the presence of Sn(Oct)(2) at 120-140 degreesC. The resulting polymers were subjected to hydrogenolysis with a Pd/C catalyst in a mixed solvent to remove the protecting benzyl groups. A novel poly(a-hydroxy acid) with pendant hydroxy groups was obtained. The hydrophilicity of the resulting polymer was evaluated preliminarily.

关键词： biodegradable polyester hydrophilicity functional pendant group

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Diabetic patients and Ramadan fasting:how they live it?

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Asian Pacific Journal of Tropical medicine 2008年第4期1卷 61-66页

作者： Hamza Mohammad Abdulghani Shaffi Ahmed Shaikh Norah Abdullah Al-Rowais Eiad Abdulmohsin Alfaris dept.of family & comm.nity medicine College of MedicineKing Saud UniversityRiyadhKingdom of Saudi Arabia

Objective:To quantify the prevalence of fasting during Ramadan month among diabetic patients and to observe the factors which were deferring between fasting and non-fasting diabetic ***:A cross-sectional study was carried out at primary health care *** diabetic patients were interviewed with a structured data form by trained research ***’age,gender,marital status,weight and height,diabetes type,medication,compliance,follow up,self monitoring and any complication faced during the fasting were *** risk factors including smoking habit,hypertension,dyslipidemia and pre-existing cardiovascular diseases were also ***:Out of 920 diabetic patients,95%were suffering from DM type *** patients who fasted the whole month of Ramadan were 84%.The proportion of type 1 and type 2 was 71%and 85%*** 63%of DM type 2 patients were treated with oral hypoglycemic agents(OHAs) alone and 2.4%with combination of OHAs and *** 42%of DM type 1 and 36%of DM type 2 patients has visited their physicians prior to their fast for *** significant differing factors which make non-fasting in diabetic patients,were medication(insulin),complications,hyperglycemia,retinopathy, neuropathy,nephropathy and vascular ***:This study has identified the factors in diabetic patients,were being compliant with medication,oral treatments and family support which lead to more likely to fast in Ramadan *** which reduce fasting by these patients were acute and chronic complications,time since diagnosis and insulin *** would be acceptable for patients who are compliant with their diet and medication.

关键词： Diabetes mellitus Fasting,Ramadan Hypoglycemic agents Insulin Saudi Arabia

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ASYMPTOTIC BEHAVIORS OF SOLUTIONS OF FRUSTRATED NEURAL NETWORKS WITH MCCULLOCH-PITTS NONLINEARITY

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Annals of Differential Equations 2003年第3期19卷 352-361页

作者：刘开宇钱祥征张弘强 College of Math. and Econometrics Hunan University Changsha 410082 dept. of Inform. and Comput. Sci. Changsha Comm. Universiiy Changsha 410076

This paper is concerned with a delay differential equationx=-x + f(y(t-r)), y=-y-f(x(t-r)),where delay r is a positive constant, and f is a signal transmission function of McCulloch-Pitts *** obtain some sufficient and necessary conditions for the asymptotic behavior of network (*) with σ ≤-1 .The results obtained show that the large time behaviors of solutions of (*) are dependent of r if σ= -1. These results improve the corresponding theorems in [3] by removing the restriction of the initial conditions.

关键词： asymptotic behavior delay differential equation oscillation neural network

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