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A survey on one-bit compressed sensing： theory and applications

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Frontiers of Computer Science 2018年第2期12卷 217-230页

作者： Zhilin LI wenbo xu Xiaobo ZHANG Jiaru LIN Key Lab of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In the past few decades, with the growing popularity of compressed sensing （CS） in the signal processing field, the quantization step in CS has received significant attention. Current research generally considers multi-bit quantization. For systems employing quantization with a sufficient number of bits, a sparse signal can be reliably recovered using various CS reconstruction algorithms. Recently, many researchers have begun studying the one- bit quantization case for CS. As an extreme case of CS, one- bit CS preserves only the sign information of measurements, which reduces storage costs and hardware complexity. By treating one-bit measurements as sign constraints, it has been shown that sparse signals can be recovered using certain reconstruction algorithms with a high probability. Based on the merits of one-bit CS, it has been widely applied to many fields, such as radar, source location, spectrum sensing, and wireless sensing network. In this paper, the characteristics of one-bit CS and related works are reviewed. First, the framework of one-bit CS is introduced. Next, we summarize existing reconstruction algorithms. Additionally, some extensions and practical applications of one-bit CS are categorized and discussed. Finally, our conclusions and the further research topics are summarized.

关键词： compressed sensing one-bit quantization sign information support consistency

系统性红斑狼疮并发股骨头坏死危险因素列线图预测模型的建立和验证

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中国组织工程研究 2025年第15期29卷 3215-3226页

作者：徐文博汪利合李松伟史鹏博河南中医药大学河南省郑州市450046 河南中医药大学第一附属医院河南省郑州市450000 河南省中医院河南省郑州市450002

背景:股骨头坏死是系统性红斑狼疮患者常见的并发症,若能早期对其发生风险进行预测与验证,将有助于避免或延缓股骨头坏死的发展。目的:分析系统性红斑狼疮患者并发股骨头坏死的危险因素,构建系统性红斑狼疮患者并发股骨头坏死的列线图... 详细信息

背景:股骨头坏死是系统性红斑狼疮患者常见的并发症,若能早期对其发生风险进行预测与验证,将有助于避免或延缓股骨头坏死的发展。目的:分析系统性红斑狼疮患者并发股骨头坏死的危险因素,构建系统性红斑狼疮患者并发股骨头坏死的列线图预测模型并进行验证。方法:回顾性分析2013年1月至2022年12月首次就诊于河南中医药大学第一附属医院的914例系统性红斑狼疮患者的病历资料,根据是否发生股骨头坏死分为发生股骨头坏死组(n=100)和未发生股骨头坏死组(n=814)。采用单因素、LASSO回归和多因素Logistic回归分析筛选和确定系统性红斑狼疮并发股骨头坏死的危险因素。同时将数据集按照7∶3的比例随机分为训练集和测试集,并基于多因素Logistic回归分析结果,构建系统性红斑狼疮并发股骨头坏死的列线图预测模型。同时,使用受试者工作特征曲线、Hosmer-Lemeshow校准曲线和决策曲线对列线图的性能进行评估。结果与结论:①股骨头坏死组与未发生股骨头坏死组患者在系统性红斑狼疮病程、系统性红斑狼疮疾病活动度评分、狼疮性肾炎、呼吸系统受累、胃肠道受累、干燥综合征、骨质疏松、抗核糖核蛋白抗体阳性、补体C3降低、环磷酰胺、吗替麦考酚酯、生物抑制剂、糖皮质激素最大日剂量、糖皮质激素冲击治疗方面差异有显著性意义(P<0.05);②采用LASSO回归分析方法筛选出10个与系统性红斑狼疮并发股骨头坏死风险相关的预测变量,将其纳入多因素Logistic回归分析,结果显示系统性红斑狼疮病程、呼吸系统受累、干燥综合征、骨质疏松、抗核糖核蛋白抗体阳性、环磷酰胺、吗替麦考酚酯、生物抑制剂、糖皮质激素最大日剂量是系统性红斑狼疮患者发生股骨头坏死的独立危险因素(P<0.05);③训练集中预测发生风险的受试者工作特征曲线下面积为0.802(95%CI=0.742-0.862),测试集预测发生股骨头坏死风险受试者工作特征曲线下面积为0.811(95%CI=0.745-0.876);Hosmer-Lemeshow校准曲线拟合度较好(训练集,P=0.447;验证集,P=0.870);决策曲线显示使用列线图预测模型预测系统性红斑狼疮患者发生股骨头坏死的风险是有益的;④月经异常为女性系统性红斑狼疮患者并发股骨头坏死的危险因素之一;⑤此次研究结果提示,系统性红斑狼疮并发股骨头坏死的危险因素是多因素的,同时建立了一个包含9个危险因素的列线图预测模型,可将其用于预测系统性红斑狼疮患者发生股骨头坏死的风险;此外,首次报道了月经异常为女性系统性红斑狼疮并发股骨头坏死的危险因素之一。

关键词：系统性红斑狼疮股骨头坏死危险因素列线图预测模型月经异常 LASSO回归多因素Logistic回归

Weighted semidefinite programming scheme for wireless positioning with lognormal shadowing

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The Journal of China Universities of Posts and Telecommunications 2023年第5期30卷 93-100页

作者： Tian Kegang xu wenbo Wang Siye Chen Xiangsen School of Artificial Intelligence Beijing University of Posts and TelecommunicationsBeijing 10876China

Received signal strength(RSS)based positioning schemes ignore the actual environmental feature that the volatility of RSS increases as signal propagation distance ***,RSS over long distance generally has relatively large measurement error and degrades the positioning *** reduce the negative impact of these RSSs over long distances,a weighted semidefinite programming(WSDP)positioning scheme was *** WSDP positioning scheme first assesses the signal propagation quality using the average variance of all RSS *** appropriate weighting factors are set based on the variance of each RSS set,and a weighted semidefinite programming optimizer is formulated to estimate the positions of target *** results show that the WSDP positioning scheme can effectively improve the positioning performance.

关键词： localization received signal strength(RSS) semidefinite programming(SDP) lognormal shadowing

Preliminary study of a cluster-based open-source parallel GIS based on the GRASS GIS

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International Journal of Digital Earth 2011年第5期4卷 402-420页

作者： Fang Huang Dingsheng Liu Xiaowen Li Lizhe Wang wenbo xu Institute of Geo-Spatial Information Technology College of AutomationUniversity of Electronic Science and Technology of ChinaChengdu 611731P.R.China Center for Earth Observation and Digital Earth Chinese Academy of SciencesBeijing 100086P.R.China School of Geography Beijing Normal UniversityBeijing 100875P.R.China Pervasive Technology Institute Indiana University2719 E.10th St.Bloomington IN 47408USA

In response to the problem of how to give geographic information system(GIS)high-performance capabilities for certain specific GIS applications,a new GIS research direction,parallel GIS processing,has ***,traditional research has focused mostly on implementing typical GIS parallel algorithms,with little discussion of how to parallelize an entire GIS package on clusters based on ***,the authors have chosen the geographic resources analysis support system(GRASS)GIS as the object of their research and have put forward the concept of a cluster-based open-source parallel GIS(cluster-based OP-GIS)as a tool to support Digital Earth *** related theory includes not only the parallel computing mode,architecture,and software framework of such a system,but also various parallelization *** experiments on the prototype system,it can be concluded that the parallel system has better efficiency and performance than the conventional system on certain selected modules.

关键词： open-source parallel GIS cluster parallel computing GRASS GIS Digital Earth

Complete protection from Henosepilachna vigintioctopunctata by expressing long double-stranded RNAs in potato plastids

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Journal of Integrative Plant Biology 2023年第4期65卷 1003-1011页

作者： wenbo xu Miao Zhang Yangcun Li Wanwan He Shengchun Li Jiang Zhang State Key Laboratory of Biocatalysis and Enzyme Engineering Hubei Hongshan LaboratorySchool of Life SciencesHubei UniversityWuhan 430062China Agricultural Genomics Institute at Shenzhen Chinese Academy of Agricultural SciencesShenzhen 518000China

RNA interference(RNAi)has emerged as a powerful technology for pest ***,we have shown that plastid-mediated RNAi(PM-RNAi)can be utilized to control the Colorado potato beetle,an insect pest in the Chrysomelidae family;however,whether this technology is suitable for controlling pests in the Coccinellidae remained *** coccinellid 28-spotted potato ladybird(Henosepilachna vigintioctopunctata;HV)is a serious pest of solanaceous *** this study,we identified three efficient target genes(β-Actin,SRP54,and SNAP)for RNAi using in vitro double-stranded RNAs(dsRNAs)fed to HV,and found that dsRNAs targetingβ-Actin messenger RNA(dsACT)induced more potent RNAi than those targeting the other two *** next generated transplastomic and nuclear transgenic potato(Solanum tuberosum)plants expressing HV *** dsACT stably accumulated to up to 0.7%of the total cellular RNA in the transplastomic plants,at least three orders of magnitude higher than in the nuclear transgenic ***,the transplastomic plants also exhibited a significantly stronger resistance to HV,killing all larvae within 6 *** data demonstrate the potential of PM-RNAi as an efficient pest control measure for HV,extending the application range of this technology to Coccinellidae pests.

关键词： double‐stranded RNA Henosepilachna vigintioctopunctata pest control plastid transformation RNA interference

Molecular Epidemiology of Echovirus 18 Circulating in China's Mainland from 2015 to 2016

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Virologica Sinica 2019年第1期34卷 50-58页

作者： Xiangpeng Chen Tianjiao Ji Jiayun Guo Wei Wang wenbo xu Zhengde Xie Key Laboratory of Major Diseases in Children Ministry of EducationNational Clinical Research Center for Respiratory DiseasesBeijing Key Laboratory of Pediatric Respiratory Infection DiseasesVirology LaboratoryBeijing Pediatric Research InstituteBeijing Children’s HospitalCapital Medical UniversityNational Center for Children’s Health WHO WPRO Regional Polio Reference Laboratory and Key Laboratory of Medical Virology and Viral Diseases National Health and Family Planning Commission of ChinaNational Institute for Viral Disease Control and PreventionChinese Center for Disease Control and Prevention

Echovirus 18(E18), a serotype of Enterovirus B(EV-B) species, is an important pathogen in aseptic meningitis. E18 had rarely been detected in China's Mainland, but became the predominant pathogen associated with viral encephalitis(VE) and meningitis in Hebei province for the first time in 2015. To investigate the molecular epidemiology and genetic characteristics of E18 in China's Mainland, sixteen E18 strains from patient throat swabs with hand, foot, and mouth disease(HFMD) in six provinces in China collected between 2015 and 2016, and four E18 strains isolated from 18 patient cerebrospinal fluid specimens with VE in Hebei Province in 2015 were obtained and sequenced. Combined with the sequences from the GenBank database, we performed an extensive genetic analysis. Phylogenetic analysis of VP1 gene sequences revealed that all E18 strains from China's Mainland after 2015 belonged to subgenotype C2. There were no obvious specific differences in phylogenetic and variation analyses of E18 genome sequences between HFMD and VE/meningitis strains. Potential multiple recombination may have occurred in the 50-untranslated region and in the P2 and P3 nonstructural protein-encoding regions of E18 strains from China. The current E18 strains were potential multiplerecombinant viruses. Overall, these findings supported that E18 caused HFMD, VE, and meningitis, although there were no significant associations between clinical features and viral genomic characteristics.

关键词： Genetic characteristics Echovirus 18 (E18) Genome Enterovirus Recombination

Stratum Griseum Periventriculare-mediated Fear Emotion Regulates Motor Behavior in Pigeons

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Journal of Bionic Engineering 2023年第5期20卷 2228-2239页

作者： wenbo xu Long Yang Zishi Wang Lifang Yang Han Cheng Shixin Zhu Zhigang Shang Zhenlong Wang School of Life Sciences Zhengzhou UniversityZhengzhou450001China School of Electrical and Information Engineering Zhengzhou UniversityZhengzhou450001China

A pigeon robot is an ideal experimental animal for research in flying animal *** majority of current research publications have entailed electrical stimulation of the motor nuclei to regulate movement forcibly,and although a“virtual fear”behavior model has been proposed,the structure,location,and function of the nuclei that generate fear emotions remain *** studies have shown that the Stratum Griseum Periventriculare(SGP)of pigeons is homologous to the mammalian periaqueductal gray(PAG),which plays an essential role in mammalian *** reveal the role of fear mediated by the SGP in behavioral regulation,we evaluated the structure and location of the SGP by histologic identification combined with magnetic resonance imaging,and analyzed the behavior of the SGP by electrical ***,the function of the SGP was verified with escape testing and homing experiments in an open *** results showed that the SGP is located in the pigeon midbrain and divided into two subregions,the dorsal part of the stratum griseum periventriculare(SGPd)and the ventral part of the stratum griseum periventriculare(SGPv)(the ranges were AP1.5–4.75 mm,ML1.75–6.75 mm,and DV2.2–7.1 mm),and that wired and wireless electrical stimulation freezing was the dominant *** the escape test,SGP electrical stimulation caused the pigeons to flee to a safe place,while in the open-field homing test,electrical stimulation of the SGP induced evasive behavior in pigeons away from their original homing *** results confirm that the SGP plays a crucial role in fear,and that electrical stimulation of this nucleus induces corresponding fear behaviors.

关键词： Pigeon cyborg Bionic robot Fear Freezing Electrical stimulation

Pigeon Robot for Navigation Guided by Remote Control:System Construction and Functional Verification

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Journal of Bionic Engineering 2021年第1期18卷 184-196页

作者： Zhengyue Zhou Denghui Liu Hong Sun wenbo xu Xinmao Tian Xiaoyuan Li Han Cheng Zhenlong Wang School of Life Sciences Zhengzhou UniversityZhengzhou 450001China School of Electrical Engineering Zhengzhou UniversityZhengzhou 450001China School of Physical Education(Main Campus) Zhengzhou UniversityZhengzhou 450001China

Animal robots have outstanding advantages over traditional robots in their own energy supplies,orientation,and natural concealment,delivering significant value in the theories and applications of neural science,national security,and other ***,many animal robots have been fabricated,but researches about the applications of avian robots are still *** this study,we constructed a Pigeon Robot System(PRS),optimized the electric stimulation parameters,assessed the electric stimulus of navigation,and evaluated the navigation efficiency in the *** pulse constant current pattern was adapted,and the optimal stimulus parameters of 4 nuclei tested were of amplitude 0.3 mA,5 pulse trains,frequency 25 Hz,5 pulses,and a 25%duty *** ratio of left and right steering behavior response to electric stimulus dorsointermedius ventralis anterior nuclei was 67%and 83%,respectively(mean value 75%).Electrical stimulation efficiency was 0.34-0.68 and path efficiency was 0.72-0.85 among pigeon robot individuals in the open *** electrical stimulation efficiency nor path efficiency differed significantly(P>0.05),suggesting that the navigational PRS performance was not biased in either *** can achieve continuous navigation along simple pathways and provide the necessary application infrastructure and technical reference for the development of animal robot navigation technology.

关键词： pigeon robot bionic robot system construction navigation functional verification

Growth performance of different Epichloësinensis strains on media with different additives

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Grassland Research 2022年第3期1卷 187-196页

作者： Pei Tian Meining Wang Yang Luo Xingdi Wang wenbo xu State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems Key Laboratory of Grassland Livestock Industry InnovationMinistry of Agriculture and Rural AffairsCollege of Pastoral Agriculture Science and TechnologyLanzhou UniversityLanzhouChina

Background:Epichloësinensis is a newly found endophyte species that is frequently involved in symbiosis with Festuca *** are a little reports on the characteristics of *** in ***:In the present study,five *** endophyte strains(strain ID 1,2,41D,57D,111D)isolated from different *** ecotypes were used to evaluate their antioxidant capacities and enzyme ***,the growth of *** on potato dextrose agar(PDA)with different additives was ***:The five strains had significantly different(p<0.05)total antioxidant capacities and radical-scavenging *** most cases,the growth rate of strain 1 was the fastest(p<0.05),and that of strain 57D was the slowest(p<0.05).The growth rates of these five strains on PDA with vitamins significantly(p<0.05)increased with increasing vitamin *** growth rates of these five strains on PDA with plant growth regulators also significantly(p<0.05)increased;however,the increase was inconsistent at different concentrations of indole-3-acetic acid and *** concentrations(5 and 10 mg L−1)of forchlorfenuron(KT-30)significantly promoted the growth of all five strains,whereas high concentrations(20 and 40 mg L−1)of KT-30 significantly inhibited their growth(p<0.05).The Na+,Cd2+,Zn2+,and Cr6+ions all inhibited the growth of these five strains,and their growth rates were significantly decreased with an increase in ion concentrations(p<0.05).Under Na+stress,strain 41D grew the fastest and had the strongest tolerance(p<0.05);under Cd2+,Zn2+,and Cr6+stresses,strain 111D grew the fastest and had the strongest tolerance(p<0.05).Conclusions:The results indicated that the *** had antioxidant activities and hydrolase *** could promote or inhibit the growth of the strains in different *** these evaluations in the present study improve our understanding of the *** endophyte and provide referenced information for further studi

关键词： antioxidant capacities enzyme profiles heavy metal ions plant growth regulator tolerance