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Optimal Price-Based Power Control Algorithm with Quality of Service Constraints in Cognitive Radio Networks

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Chinese Journal of Electronics 2015年第2期24卷 393-397页

作者： wang zhengqiang JIANG Lingge HE Chen Department of Electronic Engineering Shanghai Jiaotong University Department of Communication and Information Engineering Chongqing University of Posts and Telecommunications

In price-based cognitive radio networks,the Primary user(PU) can allow the Secondary users(SUs) to access by pricing if their interference power is under the Interference power constraint(IPC). The interaction between the PU and the SUs is modeled as a Stackelberg game with the consideration of the Quality of service(Qo S) of the SUs. The revenue maximization problem of PU is expressed as an equivalent convex optimization problem if the minimum Signal-to-interference and noise ratio(SINR) constraints for the SUs are greater than or equal to 0d B. An optimal pricing algorithm is proposed based on this equivalent convex optimization problem. Simulation results show that the proposed pricing algorithm outperforms the non-uniform pricing algorithm in terms of the revenue of the PU, the sum rate of SUs and the number of admitted SUs.

关键词： Power control Cognitive radio Price Quality of service(QoS)

User scheduling and power allocation for downlink multi-cell multi-carrier NOMA systems

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Digital Communications and Networks 2023年第1期9卷 252-263页

作者： Abuzar B.M.Adam Xiaoyu Wan zhengqiang wang School of Communications and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China

In Non-Orthogonal Multiple Access(NOMA),the best way to fully exploit the benefits of the system is the efficient resource *** the NOMA power domain,the allocation of power and spectrum require solving the mixed-integer nonlinear programming NP-hard *** this paper,we investigate user scheduling and power allocation in Multi-Cell Multi-Carrier NOMA(MCMC-NOMA)*** achieve that,we consider Weighted Sum Rate Maximization(WSRM)and Weighted Sum Energy Efficiency Maximization(WSEEM)***,we tackle the problem of user scheduling for fixed power using Fractional Programming(FP),the Lagrange dual method,and the decomposition ***,we consider Successive Pseudo-Convex Approximation(SPCA)to deal with the WSRM ***,for the WSEEM problem,SPCA is utilized to convert the problem into separable scalar problems,which can be parallelly ***,the Dinkelbach algorithm and constraints relaxation are used to characterize the closed-form solution for power *** simulations have been implemented to show the efficiency of the proposed framework and its superiority over other existing schemes.

关键词： Weighted sum rate Weighted energy efficiency Non-orthogonal multiple access Successive pseudo-convex approximation Fractional programming

Energy Efficiency Maximization for Cooperative NOMA with Hardware Impairments

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China Communications 2024年第12期21卷 80-91页

作者： wang zhengqiang Chang Ruifei Wan Xiaoyu Fan Zifu Duo Bin School of Communication and Information Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065China College of Computer Science and Cyber Security Chengdu University of TechnologyChengdu 610059China

The massive connectivity and limited energy pose significant challenges to deploy the enormous devices in energy-efficient and environmentally friendly in the Internet of Things(IoT).Motivated by these challenges,this paper investigates the energy efficiency(EE)maximization problem for downlink cooperative non-orthogonal multiple access(C-NOMA)systems with hardware impairments(HIs).The base station(BS)communicates with several users via a half-duplex(HD)amplified-and-forward(AF)***,we formulate the EE maximization problem of the system under HIs by jointly optimizing transmit power and power allocated coefficient(PAC)at BS,and transmit power at the *** original EE maximization problem is a non-convex problem,which is challenging to give the optimal solution ***,we use fractional programming to convert the EE maximization problem as a series of subtraction form ***,variable substitution and block coordinate descent(BCD)method are used to handle the ***,a resource allocation algorithm is proposed to maximize the EE of the ***,simulation results show that the proposed algorithm outperforms the downlink cooperative orthogonal multiple access(C-OMA)scheme.

关键词： block coordinate descent cooperative non-orthogonal multiple access energy efficiency hardware impairments resource allocation

Phylogenetic diversity of bacterial biofilms covering the settlement substrates of nona-porous abalones (Haliotis diversicolor supertexta)

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Acta Oceanologica Sinica 2009年第5期28卷 94-102页

作者： MA Ying wang Zhiyong CHEN zhengqiang LU Yu wang Lin The Key Laboratory of Science and Technology for Aquaculture and Food Safety Fisheries College Jimei University Xiamen 361021 China

The settlement substrates of nona-porous abalones （Haliotis diversicolor supertexta） are covered with biofilms in which several types of microorganisms coexist and interact. These microorganisms are usually important causes of juvenile abalone disease as well as organisms useful in promoting abalones’ adhesion. The bacterial community structure of the biofilms remains unclear. The aim of this research was to determine the genetic diversity and phylogenetic affiliation of the biofilm bacteria. Total DNA of bacteria in biofilms was extracted, and 16S rRNA gene clone library was constructed using the primers specific for the domain bacteria. Subsequently, 30 randomly selected positive clones were screened by PCR-restriction fragment length polymorphism （PCR-RFLP） analysis, and resulted in 15 different RFLP patterns. Sequences analysis of representatives from each unique RFLP type revealed high genetic diversity in the bacterial populations. These sequences fell into nine major lineages of the bacterial domains： α-, β-, γ-and δ-subdivisions of the Proteobacteria; Planctomycete, Actinobacteria, Firmicutes, V errucomicrobium spp., and CytophagaFlexibacter-Bacteroides spp. Phylogenetic analysis indicated that the dominant phylotypes were most closely related to environmental and clinical Burkholderia cepacia of the β-Proteobacteria, and Roseobacteria of the α-Proteobacteria.

关键词： nona-porous abalone (Haliotis diversicolor supertexta) settlement substrate bacterial biofilm 16S rRNA

Discovery of N-benzyl hydroxypyridone carboxamides as a novel and potent antiviral chemotype against human cytomegalovirus (HCMV)

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Acta Pharmaceutica Sinica B 2022年第4期12卷 1671-1684页

作者： Sameera Senaweera Tiffany C.Edwards Jayakanth Kankanala Yan wang Rajkumar Lalji Sahani Jiashu Xie Robert J.Geraghty zhengqiang wang Center for Drug Design College of PharmacyUniversity of MinnesotaMinneapolisMN 55455USA Translational Medicine R&D Center Shenzhen Institutes of Advanced TechnologyChinese Academy of SciencesShenzhen 518055China

Current drugs for treating human cytomegalovirus(HCMV)infections are limited by resistance and treatment-associated *** developing mechanistically novel HCMV antivirals,we discovered an N-benzyl hydroxypyridone carboxamide antiviral hit(8a)inhibiting HCMV in submicromolar *** describe herein the structure–activity relationship(SAR)for 8a,and the characterization of potent analogs for cytotoxicity/cytostatic property,the preliminary mechanism of action,and the absorption,distribution,metabolism and excretion(ADME)*** SAR revealed a few pharmacophore features conferring optimal antiviral profile,including the 5-OH,the N-1 benzyl,at least one–CH_(2)−in the linker,and a di-halogen substituted phenyl ring in the amide *** the end,we identified numerous analogs with sub-micromolar antiviral potency and good selectivity *** preliminary mechanism of action characterization used a pUL89-C biochemical endonuclease assay,a virus entry assay,a time-of-addition assay,and a compound withdrawal *** profiling measuring aqueous solubility,plasma and liver microsomal stability,and parallel artificial membrane permeability assay(PAMPA)permeability demonstrated largely favorable drug-like ***,these studies validate the N-benzyl hydroxypyridone carboxamide as a viable chemotype for potent and mechanistically distinct antivirals against HCMV.

关键词： Human cytomegalovirus N-Benzyl hydroxypyridone carboxamides Structureeactivity relationship Mechanism of action

Novel PF74-like small molecules targeting the HIV-1 capsid protein:Balance of potency and metabolic stability

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Acta Pharmaceutica Sinica B 2021年第3期11卷 810-822页

作者： Lei wang Mary CCasey Sanjeev Kumar VVernekar Rajkumar Lalji Sahani Karen AKirby Haijuan Du Huanchun Zhang Philip RTedbury Jiashu Xie Stefan GSarafianos zhengqiang wang Center for Drug Design College of PharmacyUniversity of MinnesotaMN 55455USA Department of Pharmaceutical Sciences School of Chemical EngineeringDalian University of TechnologyDalian 116024China Department of Molecular Microbiology and Immunology University of Missouri School of MedicineChristopher S.Bond Life Sciences CenterColumbiaMO 65211USA Laboratory of Biochemical Pharmacology Department of PediatricsEmory University School of MedicineAtlantaGA 30322USA

Of all known small molecules targeting human immunodeficiency virus(HIV)capsid protein(CA),PF74 represents by far the best characterized chemotype,due to its ability to confer antiviral phenotypes in both early and late phases of viral ***,the prohibitively low metabolic stability renders PF74 a poor antiviral *** report herein our medicinal chemistry efforts toward identifying novel and metabolically stable small molecules targeting the PF74 binding ***,we replaced the inter-domain-interacting,electron-rich indole ring of PF74 with less electron-rich isosteres,including imidazolidine-2,4-dione,pyrimidine-2,4-dione,and benzamide,and identified four potent antiviral compounds(10,19,20 and 26)with markedly improved metabolic *** to PF74,analog 20 exhibited similar submicromolar potency,and much longer(51-fold)half-life in human liver microsomes(HLMs).Molecular docking corroborated that 20 binds to the PF74 binding site,and revealed distinct binding interactions conferred by the benzamide ***,our data support compound 20 as a promising antiviral lead.

关键词： HIV-1 Capsid protein PF74 Microsomal stability

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专题:面向B5G/6G的无人机通信

无线电工程 2023年第1期53卷 1-2页

作者：王正强重庆邮电大学通信与信息工程学院

内容导读随着无线通信技术的迅猛发展,通信网络面临着海量数据传输与连接密度激增的严峻挑战。无人机通信具有移动性、稳定性和广覆盖等优势,加之具有高质量的空地无线信道,可以作为空中基站或中继节点辅助地面通信,也可以作为信息采集... 详细信息

内容导读随着无线通信技术的迅猛发展,通信网络面临着海量数据传输与连接密度激增的严峻挑战。无人机通信具有移动性、稳定性和广覆盖等优势,加之具有高质量的空地无线信道,可以作为空中基站或中继节点辅助地面通信,也可以作为信息采集和数据传输手段用于遥测遥感和物联网应用等领域。现有的无人机通信方案主要采用非授权频段进行直连通信,具有速率低、可靠性差、安全性差、易受干扰、较难监控和管理等缺点。为了克服上述缺点,将无人机集成到蜂窝通信系统中来支持未来的B5G/6G网络对地面和非地面一体化通信需求,作为地面通信的有益补充,面向B5G/6G的无人机通信的研究已经成为学术界、产业界的一个研究热点。由于无人机通信系统特有的信道特性和无人机飞行高度、机动性、尺寸、质量和功率等限制,如何针对面向B5G/6G的无人机通信系统进行资源管理和实际应用面临许多新的问题和挑战。随着国内外相关学者在无人机通信领域的研究工作不断深入,在多个研究方向都获得了新的研究进展和成果。鉴于此,《无线电工程》2023年第1期推出“面向B5G/6G的无人机通信”专题。专题内容涵盖无人机集群通信、无人机资源管理和无人机应用3个研究方向的相关成果。

关键词：地面通信蜂窝通信系统无线通信技术通信网络资源管理移动性广覆盖专题内容

腹腔镜胃癌根治术与开腹胃癌根治术治疗胃癌疗效比较

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新乡医学院学报 2020年第4期37卷 386-390页

作者：王政强王春长安医院普外科陕西西安710016

目的比较腹腔镜胃癌根治术与开腹胃癌根治术治疗胃癌的临床效果。方法选择2014年6月至2018年8月长安医院收治的127例胃癌患者为研究对象,根据手术方法将患者分为腹腔镜手术组(n=64)和开腹手术组(n=63);开腹手术组患者采用开腹胃癌根治... 详细信息

目的比较腹腔镜胃癌根治术与开腹胃癌根治术治疗胃癌的临床效果。方法选择2014年6月至2018年8月长安医院收治的127例胃癌患者为研究对象,根据手术方法将患者分为腹腔镜手术组(n=64)和开腹手术组(n=63);开腹手术组患者采用开腹胃癌根治术治疗,腹腔镜手术组患者采用腹腔镜胃癌根治术治疗。观察2组患者手术时间、术中出血量、手术切口长度、术后住院时间及术后肛门排气时间,分别于术前及术后第3天检测血清一氧化氮(NO)、内皮素-1(ET-1)、血红素加氧酶-1(HO-1)、β-内啡肽(β-EP)水平及凝血酶原时间(PT)、纤维蛋白原(FIB)、活化部分凝血活酶时间(ATPP),计算国际标准化比值(INR)。观察2组患者术后并发症发生情况。结果与开腹手术组比较,腹腔镜手术组患者手术时间短,术中出血量少,手术切口短,术后肛门排气早,术后住院时间短(P0.05);开腹手术组患者术后第3天血清NO、ET-1、HO-1及β-EP水平显著高于术前(P0.05);术后第3天,腹腔镜手术组患者血清NO、ET-1、HO-1及β-EP水平显著低于开腹手术组(P0.05)。开腹手术组患者术后第3天PT显著短于术前,血浆FIB水平显著高于术前(P0.05)。腹腔镜手术组患者术后第3天PT、APTT短于术前,INR显著小于术前,血浆FIB水平显著高于术前(P<0.05)。术后第3天,腹腔镜手术组患者血浆FIB水平高于开腹手术组,PT、APTT短于开腹手术组,INR小于开腹手术组(P<0.05)。腹腔镜手术组和开腹手术组患者并发症发生率分别为6.25%(4/64)、19.05%(12/63),腹腔镜手术组患者并发症发生率低于开腹手术组(χ^2=4.434,P<0.05)。结论与开腹胃癌根治术比较,腹腔镜胃癌根治术具有术中出血量少、手术应激反应小、并发症少等优势,但腹腔镜胃癌根治术对患者的凝血功能影响较大,应注意预防凝血功能异常所致术后血栓形成。

关键词：胃癌腹腔镜手术开腹手术胃癌根治术

不等厚高强度钢H220YD/DP590GA电阻点焊接头的组织和性能

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上海交通大学学报 2016年第12期50卷 1889-1892页

作者：王小乐朱政强赵翔南昌大学机电工程学院南昌330038

针对不等厚H220YD/DP590GA先进高强度钢焊接时出现的薄板变形严重、力学性能差等问题,在大量前期实验的基础上,选取最优的主焊接工艺参数进行电阻点焊实验,并利用拉剪测试、金相组织分析等手段对试样进行组织和性能研究.结果表明,焊接... 详细信息

针对不等厚H220YD/DP590GA先进高强度钢焊接时出现的薄板变形严重、力学性能差等问题,在大量前期实验的基础上,选取最优的主焊接工艺参数进行电阻点焊实验,并利用拉剪测试、金相组织分析等手段对试样进行组织和性能研究.结果表明,焊接接头受焊接热影响,使得H220YD钢铁素体晶粒尺寸变大,DP590GA钢板母材的岛状马氏体演变成板条状马氏体,其失效形式为钮扣状断裂.

关键词：先进高强度钢电阻点焊差强差厚组织性能焊接接头