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Malaria Illness and Accessing Healthcare in an African Indigenous Population: A Qualitative Study of the Lived Experiences of Uganda’s Batwa in Kanungu District
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作者 Didacus B. Namanya Everd M. Bikaitwoha +4 位作者 Lea Berrang-Ford Shuiaib Lwasa Charity Kesande Sabastian Twesigomwe Ronald Nyakol 《Journal of Biosciences and Medicines》 CAS 2023年第5期212-232,共21页
Purpose: Malaria continues to be a public health threat, especially in sub-Saharan Africa, including Uganda. While Batwa Indigenous People (IPs) face a higher burden of malaria, there is limited understanding of their... Purpose: Malaria continues to be a public health threat, especially in sub-Saharan Africa, including Uganda. While Batwa Indigenous People (IPs) face a higher burden of malaria, there is limited understanding of their malaria-lived experiences. We assessed and characterized malaria illness and accessing healthcare lived experiences of the Batwa in Kanungu district to inform contextually and culturally appropriate public health interventions. Methods: An exploratory qualitative study was conducted in 5 Batwa settlements where 5 Focus Group Discussions (n = 36) and 13 Key Informant Interviews (n = 13) were held. Data were collected using printed guides and voice recorders in April 2018. Transcripts from the data that captured the lived experiences of the symptoms, prevention, treatment and barriers to accessing formal healthcare services were applied to Atlas.ti a qualitative data analysis software and condensed into codes, categories, and themes. Results: Many Batwa have experienced malaria in their households, and they know its causes and risk factors, like not sleeping under insecticide-treated mosquito nets (ITNs), living near water bodies, prevention measures like the use of ITNs, and vector management. The lived experiences demonstrate malaria management by an Indigenous population in a rural setting and comprised detecting malaria symptoms, use of herbs as first line of treatment, buying medicines from drug shops, and village health teams (VHTs) treatment. For many Batwa accessing formal healthcare is normally a second option. Barriers for malaria treatment included: long distances to health facilities, geographically difficult terrain, economic constraints, irregular health outreaches, and stockouts of malaria medicines at health facilities. Conclusion: This study characterized Batwa’s malaria illness lived experiences and access to healthcare in rural remote settings. These experiences are essential in appreciating the ways in which Indigenous populations understand and manage common illnesses and how appropriate policies and interventions can be developed. 展开更多
关键词 accessing Healthcare Batwa IPs Lived Experiences Malaria Illness Uganda
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Morbi-Mortality Linked to Unsafe Abortions—Difficulties in Accessing Safe Abortions in Cameroon: Meta-Analysis and Systematic Review
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作者 Florent Ymele Fouelifack Mosman Anyimbi Ofeh +5 位作者 Jenny Ornella Manewoun Nsen Abeng Christophe Saha Lontsi Mvong Vendeline Amaelle Goretti Guy Sadeu Wafeu Robinson Enow Mbu 《Open Journal of Obstetrics and Gynecology》 CAS 2023年第2期342-359,共18页
Background: Unsafe abortions are one of the leading causes of maternal mortality, especially in developing countries. In Cameroon, the maternal mortality rate remains high, and the scarcity of data on abortions leads ... Background: Unsafe abortions are one of the leading causes of maternal mortality, especially in developing countries. In Cameroon, the maternal mortality rate remains high, and the scarcity of data on abortions leads to a lack of solid evidence to advocate on the extent of the abortions related complications. Our objective was to evaluate the unsafe abortions related complications, and to assess the difficulties of accessing safe abortions in our setting. Methods: We carried out a meta-analytic and systematic review in the biomedical databases MEDLINE (Pubmed), Google Scholar and African Journal Online concerning unsafe abortions and/or difficulties in accessing safe abortions in Cameroon. The keywords used for the search are seen in table I. Selection of studies was simultaneously done by two authors. Data were extracted through a form designed on Google Form. We used a random-effect model for proportion estimation, and The I<sup>2</sup> and Q statistics to assess the extent of heterogeneity. Results: A total of 430 studies were identified, from which 28 were included and analysed. About 5% (95% CI: 3 - 7) of unsafe abortions leads to death. The contribution of unsafe abortions in maternal deaths was 23% (95% CI: 20 - 27). The rate of severe bleeding and/or anemia were 40% (95% CI: 18 - 63) and the rate of infection was 17% (95% CI: 7 - 28), dominated by pelvic infections, pelviperitonitis, severe sepsis, and septic shock. Case reports described uterine perforations, uterine rupture during the following pregnancy. Abortion was performed in the practitioner’s or patient’s home in 41.4% of cases, in a health center in 35.1% of cases, in a private clinic in 21.2% of cases, drugs selling places and in traditional healer clinics. The restriction of abortion laws, the stigma surrounding abortion and its consequences at any level of the society, lead to the underreporting of unsafe abortions and a deep reluctance to advocate for safe abortion services. Conclusion: The strengthening of awareness campaigns for provider behavior change communication, family planning, the de-stigmatization of abortions, the training of health personnel in post-abortion care, a multidisciplinary and multicentric action would contribute to the reduction in morbidity and mortality due to abortions. 展开更多
关键词 Morbi-Mortality Unsafe DIFFICULTIES Access SAFE ABORTION Cameroon
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Predictive Decision and Reliable Accessing for UAV Communication in Space-Air-Ground Integrated Networks 被引量:1
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作者 Bowen Zeng Zhongshan Zhang +2 位作者 Xuhui Ding Xiangyuan Bu Jianping An 《China Communications》 SCIE CSCD 2022年第1期166-185,共20页
The cooperation of multiple Unmanned Aerial Vehicles(UAVs) has become a promising scenario in Space-Air-Ground Integrated Networks(SAGINs) recently due to their widespread applications,where wireless communication is ... The cooperation of multiple Unmanned Aerial Vehicles(UAVs) has become a promising scenario in Space-Air-Ground Integrated Networks(SAGINs) recently due to their widespread applications,where wireless communication is a basic necessity and is normally categorized into control and nonpayload communication(CNPC) as well as payload communication. In this paper, we attempt to tackle two challenges of UAV communication respectively on establishing reliable CNPC links against the high mobility of UAVs as well as changeable communication conditions, and on offering dynamic resource optimization for Quality-of-Service(QoS) guaranteed payload communication with variable link connectivity. Firstly, we propose the concept of air controlling center(ACC), a virtual application equipped on the infrastructure in SAGINs, which can collect global information for estimating UAV trajectory and communication channels. We then introduce the knapsack problem for modelling resource optimization of UAV communication in order to provide optimal access points for both CNPC and payload communication. Meanwhile, using the air controlling information, predictive decision algorithm and handover strategy are introduced for the reliable connection with multiple access points. Simulation results demonstrate that our proposal ensures an approximate always-on reliable accessing of communication links and outperforms the existing methods against high mobility,sparse distribution, and physical obstacles. 展开更多
关键词 space-air-ground integrated networks UAV communication air communication controlling predictive decision reliable accessing
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The effect of urine pregnancy testing on timing of accessing antenatal care and abortion services in Western Nigeria
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作者 Mustafa Adelaja Lamina 《Open Journal of Obstetrics and Gynecology》 2013年第6期486-492,共7页
Objective: Effective confirmation of pregnancy is a basic component of reproductive health services. It is a determinant for accessing antenatal care (ANC) if the pregnancy is wanted and abortion services if the pregn... Objective: Effective confirmation of pregnancy is a basic component of reproductive health services. It is a determinant for accessing antenatal care (ANC) if the pregnancy is wanted and abortion services if the pregnancy is unwanted. This study examined the effect of urine pregnancy testing in the timing of presentation for pregnancy care. Method: A cross-sectional study was conducted among 320 women presenting for antenatal care and 300 women presenting for abortion at private sector clinics in Western Nigeria. Results: The median age at first presentation was 20 weeks for ANC clients and 8 weeks for abortion clients. Obtaining urine pregnancy test of one’s accord was associated with a decrease in the gestational age at presentation of 3.7 weeks and 1.5 weeks for antenatal and abortion clients, respectively, independent of all other factors. Conclusion: Bearing in mind that the clinical benefit and public health impact of early presentation for antenatal and abortion services are unequivocal, strategies aimed at decreasing gestational age at presentation for pregnancy care should be given priority. “Fast-track” urine pregnancy testing services should be promoted in the private and public clinics in Nigeria. 展开更多
关键词 URINE PREGNANCY Testing TIMING accessing ANTENATAL ABORTION
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Contribution of safe motherhood solidarity groups in using and accessing maternity services during a period of armed conflict
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作者 Richard Bitwe Mihanda Jean Robert Likofata Gwendolyn J. Lusi 《Health》 2013年第7期1085-1091,共7页
This report presents the results of a study on Reproductive Health done in North Kivu in September 2009. It was conducted by HEAL Africa, in partnership with the Provisional Division of Health, and financed by the Uni... This report presents the results of a study on Reproductive Health done in North Kivu in September 2009. It was conducted by HEAL Africa, in partnership with the Provisional Division of Health, and financed by the University of Ottawa, Canada/CRDI with technical assistance from Western Cape University of South Africa. The study was conducted in the health zones of Birambizo and Kayna within the framework of the central office. The focus of the report is on one aspect of Reproductive Health—Low Risk Maternity. This study was conducted in rural areas given that Reproductive Health indicators are much weaker when compared with urban areas, according to EDS RDC, 2007 [1]. This study emphasizes the following points: General characteristics of the participants in the study, and the utilization and accessibility of maternity services in rural areas in conflict situations. The formula SPSS 12.0.1 was used to facilitate data analysis in the study. This study comes at a point in time when its relevance to HEAL Africa’s work will assist HEAL and its partners in determining the focus of interventions done in health zones in order to improve maternal and neonatal health. HEAL Africa firstly stepped into a Safe Motherhood pilot project in June 2006 for 9 months in the Masisi zone, then in 2007 in the Birambizo and Kayna health zones. In November 2007, HEAL expanded into Walikale and in October 2008, into Kirotshe, Binza, and Lubero. The intervention kit consists of reinforcing the capacity of existing health facilities, training traditional midwives who serve as a link between the community and the health structures, the provision of sanitary equipment, medical essentials and community mobilization was done through local leaders about health and reproduction, and organizing women of reproductive age in solidarity groups (SG) to generate maternity insurance. The community approach “Solidarity Groups for Maternity Insurance” constitutes the spine of HEAL Africa within the support it provides in Reproductive Health. The principal idea is to educate and train communities on how to use the MMR services that are available in their community, and to remove financial barriers to accessing health services. The 4 pillars that comprise the Safe Motherhood program are: family planning, prenatal care, safe assisted delivery and essential obstetric care. These four strategic measures are integral in assuring primary health care and equality for women. This study evaluates this approach, keeping in mind local strategies and their effects on improving the utilization and accessibility of reproductive health services. 展开更多
关键词 Safe MOTHERHOOD SOLIDARITY Group Usage of MATERNITY SERVICES Accessibility of MATERNITY SERVICES REPRODUCTIVE HEALTH Maternal HEALTH
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Morbidity and Mortality Linked to Unsafe Abortions in Cameroon—Difficulties in Accessing Safe Abortions: Systematic Review and Meta-Analysis. A Study Proposal
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作者 Florent Ymele Fouelifack Ako William Takang +4 位作者 Mosman Anyimbi Ofeh Jenny Ornella Manewoun Nsen Abeng Guy Sadeu Wafeu Christophe Lontsi Saha 《Open Journal of Obstetrics and Gynecology》 CAS 2022年第10期1102-1112,共11页
Unsafe abortions constitute a public health problem. It is one of the causes of maternal mortality in the world and particularly in developing countries. Despite the progress made, maternal mortality remains high in C... Unsafe abortions constitute a public health problem. It is one of the causes of maternal mortality in the world and particularly in developing countries. Despite the progress made, maternal mortality remains high in Cameroon. The scarcity and disparity of data on abortions lead to a lack of strong evidence to advocate to decision-makers on the extent of the problems associated with abortions in Cameroon. Our objective is to estimate the rates of mortalities and complications related to unsafe abortions, as well as the difficulties of accessing safe abortions in Cameroon. We will carry out a systematic and meta-analytical review in the biomedical databases MEDLINE (Pubmed), Google Scholar and African Journal Online (AJOL) concerning unsafe abortions and/or difficulties in accessing safe abortions in Cameroon, without date or language restriction. Gray literature will be also consulted. Two authors will simultaneously select the studies and data extraction will be done using a Google Form. Proportions will be estimated on a random-effect model. The I<sup>2</sup> and Q statistics will be used to assess the extent of heterogeneity across the studies. The outcome of both the quantitative and qualitative parts of the study will be commented. Death and morbidity due to abortions can be prevented. A concerted multidisciplinary and multicentric action would be essential. 展开更多
关键词 MORTALITY MORBIDITY DIFFICULTIES Access Unsafe Abortion Cameroon
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Australian children living with rare diseases:health service use and barriers to accessing care
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作者 Suzy Teutsch Yvonne Zurynski +6 位作者 Guy DEslick Marie Deverell John Christodoulou Helen Leonard Troy Dalkeith Sandra LJJohnson Elizabeth JElliott 《World Journal of Pediatrics》 SCIE CSCD 2023年第7期701-709,共9页
Background Children with rare diseases experience challenges at home and school and frequently require multi-disciplinary healthcare.We aimed to determine health service utilization by Australian children with rare di... Background Children with rare diseases experience challenges at home and school and frequently require multi-disciplinary healthcare.We aimed to determine health service utilization by Australian children with rare diseases and barriers to access-ing healthcare.Methods Parents completed an online survey on health professional and emergency department(ED)presentations,hospi-talization,and barriers to accessing services.Potential barriers to service access included residential location(city,regional,remote)and child health-related functioning,determined using a validated,parent-completed measure-of-function tool.Results Parents of 462 children with over 240 rare diseases completed the survey.Compared with the general population,these children were more likely to be hospitalized[odds ratio(OR)=17.25,95%confidence interval(CI)=15.50-19.20]and present to the ED(OR=4.15,95%CI=3.68-4.68)or a family physician(OR=4.14,95%CI=3.72-4.60).Child functional impairment was nil/mild(31%),moderate(48%)or severe(22%).Compared to children with nil/mild impair-ment,those with severe impairment were more likely to be hospitalized(OR=13.39,95%CI=7.65-23.44)and present to the ED(OR=11.16,95%CI=6.46-19.27).Most children(75%)lived in major cities,but children from regional(OR=2.78,95%CI=1.72-4.55)and remote areas(OR=9.09,95%CI=3.03-25.00)experienced significantly more barriers to healthcare access than children from major cities.Barriers included distance to travel,out-of-pocket costs,and lack of specialist medical and other health services.Conclusions Children with rare diseases,especially those with severe functional impairment have an enormous impact on health services,and better integrated multidisciplinary services with patient-centered care are needed.Access must be improved for children living in rural and remote settings. 展开更多
关键词 ACCESS Health functioning Health service use Rare diseases
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Secure storage and accessing the data in cloud using optimized homomorphic encryption
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作者 S.Gnana Sophia K.K.Thanammal S.S.Sujatha 《Journal of Control and Decision》 EI 2023年第1期90-98,共9页
Different efforts have been undertaken to customizing a security and privacy concern in clouddata access. Therefore, the security measures are reliable and the data access was verified as themajor problem in the cloud... Different efforts have been undertaken to customizing a security and privacy concern in clouddata access. Therefore, the security measures are reliable and the data access was verified as themajor problem in the cloud environment. To overcome this problem, we proposed an efficientdata access control using optimized homomorphic encryption (HE). Because users outsourcetheir sensitive information to cloud providers, data security and access control is one of themost difficult ongoing cloud computing research projects. Existing solutions that rely on cryptographictechnologies to address these security issues result in significant complexity for bothdata and cloud service providers. The experimental results show that the key generation is 7.6%decreased by HE and 14.14% less than the proposed method. The encryption time is 11.34% lessthan the optimized HE and 23.28% decreased by ECC. The decryption time is 13.18% and 24.07%when compared with HE and ECC respectively. 展开更多
关键词 Homomorphic encryption(HE) elliptical curve cryptography(ECC) data security cloud computing data access
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The impact of Internet access on household dietary quality:Evidence from rural China 被引量:1
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作者 Yi Cui Qiran Zhao +1 位作者 Thomas Glauben Wei Si 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期374-383,共10页
Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access sig... Over the past few decades,the Internet has rapidly diffused across China.The spread of the Internet has had a profound economic and social impact on Chinese rural areas.Existing research shows that Internet access significantly impacts agricultural production and improves smallholder farmers’income.Beyond these,the Internet can affect other dimensions of social welfare.However,research about the impact of Internet access on dietary quality in rural China remains scarce.This study utilizes multi-period panel data from Fixed Observation Point in rural China from 2009 to 2015 to estimate the impact of Internet access on dietary quality and food consumption of rural households and conducts a causal analysis.Regression models with time and household fixed effects allow robust estimation while reducing potential issues of unobserved heterogeneity.The estimates show that Internet access has significantly increased rural household dietary quality(measured by the Chinese Diet Balance Index).Further research finds that Internet access has increased the consumption of animal products,such as aquatic and dairy products.We also examine the underlying mechanisms.Internet access improves dietary quality and food consumption mainly through increasing household income and food expenditure.These results encourage the promotion of Internet access as a valuable tool for nutritional improvements,especially in rural areas. 展开更多
关键词 dietary quality fixed effect model Internet access rural China
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Glycine-β-cyclodextrin-assisted cometabolism of phenanthrene and pyrene by Pseudomonas stutzeri DJP 1 from marine sediment
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作者 Junfeng JIANG Weijun TIAN +3 位作者 Zhiyang LU Meile CHU Huimin CAO Dantong ZHANG 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第2期560-569,共10页
Cometabolic degradation is currently an effective and extensively way to remove high molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs).Unfortunately,due to low bio-accessibility and high biotoxicity,the come... Cometabolic degradation is currently an effective and extensively way to remove high molecular weight polycyclic aromatic hydrocarbons(HMW-PAHs).Unfortunately,due to low bio-accessibility and high biotoxicity,the cometabolic degradation rate of HMW-PAHs is limited.Glycine-β-cyclodextrin(GCD)was obtained through amino modification ofβ-cyclodextrin(BCD)and added to cometabolic system of phenanthrene(PHE)and pyrene(PYR)to assist PYR biodegradation.Results show that the addition of GCD(100 mg/L)effectively improved the removal rate of PYR(20 mg/L)by 42.3%.GCD appeared to increase the bio-accessibility and reduce the biotoxicity of PHE and PYR,and then promoted the growth of Pseudomonas stutzeri DJP1 and stimulated the elevation of dehydrogenase(DHA)and catechol 12 dioxygenase(C12O)activities.The phthalate metabolic pathway was accelerated,which improved the cometabolic degradation.This study provided a new reference for the cometabolic degradation of HMW-PAHs. 展开更多
关键词 COMETABOLISM PHENANTHRENE PYRENE glycine-β-cyclodextrin biological accessibility biotoxicity
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OFDMA-Based Unsourced Random Access in LEO Satellite Internet of Things
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作者 Jiaqi Fang Gangle Sun +2 位作者 Wenjin Wang Li You Rui Ding 《China Communications》 SCIE CSCD 2024年第1期13-23,共11页
This paper investigates the low earth orbit(LEO)satellite-enabled coded compressed sensing(CCS)unsourced random access(URA)in orthogonal frequency division multiple access(OFDMA)framework,where a massive uniform plana... This paper investigates the low earth orbit(LEO)satellite-enabled coded compressed sensing(CCS)unsourced random access(URA)in orthogonal frequency division multiple access(OFDMA)framework,where a massive uniform planar array(UPA)is equipped on the satellite.In LEO satellite communications,unavoidable timing and frequency offsets cause phase shifts in the transmitted signals,substantially diminishing the decoding performance of current terrestrial CCS URA receiver.To cope with this issue,we expand the inner codebook with predefined timing and frequency offsets and formulate the inner decoding as a tractable compressed sensing(CS)problem.Additionally,we leverage the inherent sparsity of the UPA-equipped LEO satellite angular domain channels,thereby enabling the outer decoder to support more active devices.Furthermore,the outputs of the outer decoder are used to reduce the search space of the inner decoder,which cuts down the computational complexity and accelerates the convergence of the inner decoding.Simulation results verify the effectiveness of the proposed scheme. 展开更多
关键词 LEO OFDMA SATELLITE unsourced random access UPA
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基于BOPPPS模型和思维导图的Access数据库课程教学设计
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作者 于惠雯 赵艺洁 《集成电路应用》 2024年第1期82-83,共2页
阐述BOPPPS模式和思维导图开展Access数据库课程教学设计,分析BOPPPS模型和思维导图的特点,探讨Access数据库课程教学设计中的应用,包括课堂引入、课程目标、参与式学习、考试评估。
关键词 思维导图 ACCESS数据库 课程设计 BOPPPS模型
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6G New Multiple Access Technology
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作者 Yifei Yuan Yongpeng Wu +3 位作者 Lei Wang Zhifeng Yuan Wei Bai Yuanwei Liu 《China Communications》 SCIE CSCD 2024年第1期I0002-I0005,共4页
As a basic technology at physical layer of mobile communications,non-orthogonal multiple access has been attracting wide attention across the academia and the industry.During the standardization of the fifth-generatio... As a basic technology at physical layer of mobile communications,non-orthogonal multiple access has been attracting wide attention across the academia and the industry.During the standardization of the fifth-generation(5G)of mobile communications,3GPP conducted preliminary study on non-orthogonal multiple access without reaching the consensus to standardize the technology. 展开更多
关键词 TECHNOLOGY ACCESS attracting
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Design Framework of Unsourced Multiple Access for 6G Massive IoT
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作者 Chunlin Yan Siying Lyu +2 位作者 Sen Wang Yuhong Huang Xiaodong Xu 《China Communications》 SCIE CSCD 2024年第1期1-12,共12页
In this paper,ambient IoT is used as a typical use case of massive connections for the sixth generation(6G)mobile communications where we derive the performance requirements to facilitate the evaluation of technical s... In this paper,ambient IoT is used as a typical use case of massive connections for the sixth generation(6G)mobile communications where we derive the performance requirements to facilitate the evaluation of technical solutions.A rather complete design of unsourced multiple access is proposed in which two key parts:a compressed sensing module for active user detection,and a sparse interleaver-division multiple access(SIDMA)module are simulated side by side on a same platform at balanced signal to noise ratio(SNR)operating points.With a proper combination of compressed sensing matrix,a convolutional encoder,receiver algorithms,the simulated performance results appear superior to the state-of-the-art benchmark,yet with relatively less complicated processing. 展开更多
关键词 channel coding compressed sensing massive Internet-of-Things(IoT) sparse interleaverdivision multiple access(SIDMA) the sixth generation(6G)mobile communications unsourced multiple access
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Scenario Modeling-Aided AP Placement Optimization Method for Indoor Localization and Network Access
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作者 Pan Hao Chen Yu +1 位作者 Qi Xiaogang Liu Meili 《China Communications》 SCIE CSCD 2024年第3期37-50,共14页
Owing to the ubiquity of wireless networks and the popularity of WiFi infrastructures,received signal strength(RSS)-based indoor localization systems have received much attention.The placement of access points(APs)sig... Owing to the ubiquity of wireless networks and the popularity of WiFi infrastructures,received signal strength(RSS)-based indoor localization systems have received much attention.The placement of access points(APs)significantly influences localization accuracy and network access.However,the indoor scenario and network access are not fully considered in previous AP placement optimization methods.This study proposes a practical scenario modelingaided AP placement optimization method for improving localization accuracy and network access.In order to reduce the gap between simulation-based and field measurement-based AP placement optimization methods,we introduce an indoor scenario modeling and Gaussian process-based RSS prediction method.After that,the localization and network access metrics are implemented in the multiple objective particle swarm optimization(MOPSO)solution,Pareto front criterion and virtual repulsion force are applied to determine the optimal AP placement.Finally,field experiments demonstrate the effectiveness of the proposed indoor scenario modeling method and RSS prediction model.A thorough comparison confirms the localization and network access improvement attributed to the proposed anchor placement method. 展开更多
关键词 indoor localization MOPSO network access RSS prediction
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A Blockchain-Based Access Control Scheme for Reputation Value Attributes of the Internet of Things
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作者 Hongliang Tian Junyuan Tian 《Computers, Materials & Continua》 SCIE EI 2024年第1期1297-1310,共14页
The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data tampering.To address these issues,a blockchain-based IoT reputation value attribute access cont... The Internet of Things(IoT)access controlmechanism may encounter security issues such as single point of failure and data tampering.To address these issues,a blockchain-based IoT reputation value attribute access control scheme is proposed.Firstly,writing the reputation value as an attribute into the access control policy,and then deploying the access control policy in the smart contract of the blockchain system can enable the system to provide more fine-grained access control;Secondly,storing a large amount of resources fromthe Internet of Things in Inter Planetary File System(IPFS)to improve system throughput;Finally,map resource access operations to qualification tokens to improve the performance of the access control system.Complete simulation experiments based on the Hyperledger Fabric platform.Fromthe simulation experimental results,it can be seen that the access control system can achieve more fine-grained and dynamic access control while maintaining high throughput and low time delay,providing sufficient reliability and security for access control of IoT devices. 展开更多
关键词 Blockchain IOT access control Hyperledger Fabric
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The study of lithographic variation in resistive random access memory
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作者 Yuhang Zhang Guanghui He +2 位作者 Feng Zhang Yongfu Li Guoxing Wang 《Journal of Semiconductors》 EI CAS CSCD 2024年第5期69-79,共11页
Reducing the process variation is a significant concern for resistive random access memory(RRAM).Due to its ultrahigh integration density,RRAM arrays are prone to lithographic variation during the lithography process,... Reducing the process variation is a significant concern for resistive random access memory(RRAM).Due to its ultrahigh integration density,RRAM arrays are prone to lithographic variation during the lithography process,introducing electrical variation among different RRAM devices.In this work,an optical physical verification methodology for the RRAM array is developed,and the effects of different layout parameters on important electrical characteristics are systematically investigated.The results indicate that the RRAM devices can be categorized into three clusters according to their locations and lithography environments.The read resistance is more sensitive to the locations in the array(~30%)than SET/RESET voltage(<10%).The increase in the RRAM device length and the application of the optical proximity correction technique can help to reduce the variation to less than 10%,whereas it reduces RRAM read resistance by 4×,resulting in a higher power and area consumption.As such,we provide design guidelines to minimize the electrical variation of RRAM arrays due to the lithography process. 展开更多
关键词 layout LITHOGRAPHY process variation resistive random access memory
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Cluster-Based Massive Access for Massive MIMO Systems
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作者 Shiyu Liang Wei Chen +2 位作者 Zhongwen Sun Ao Chen Bo Ai 《China Communications》 SCIE CSCD 2024年第1期24-33,共10页
Massive machine type communication aims to support the connection of massive devices,which is still an important scenario in 6G.In this paper,a novel cluster-based massive access method is proposed for massive multipl... Massive machine type communication aims to support the connection of massive devices,which is still an important scenario in 6G.In this paper,a novel cluster-based massive access method is proposed for massive multiple input multiple output systems.By exploiting the angular domain characteristics,devices are separated into multiple clusters with a learned cluster-specific dictionary,which enhances the identification of active devices.For detected active devices whose data recovery fails,power domain nonorthogonal multiple access with successive interference cancellation is employed to recover their data via re-transmission.Simulation results show that the proposed scheme and algorithm achieve improved performance on active user detection and data recovery. 展开更多
关键词 compressive sensing dictionary learning multiuser detection random access
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Big Data Access Control Mechanism Based on Two-Layer Permission Decision Structure
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作者 Aodi Liu Na Wang +3 位作者 Xuehui Du Dibin Shan Xiangyu Wu Wenjuan Wang 《Computers, Materials & Continua》 SCIE EI 2024年第4期1705-1726,共22页
Big data resources are characterized by large scale, wide sources, and strong dynamics. Existing access controlmechanisms based on manual policy formulation by security experts suffer from drawbacks such as low policy... Big data resources are characterized by large scale, wide sources, and strong dynamics. Existing access controlmechanisms based on manual policy formulation by security experts suffer from drawbacks such as low policymanagement efficiency and difficulty in accurately describing the access control policy. To overcome theseproblems, this paper proposes a big data access control mechanism based on a two-layer permission decisionstructure. This mechanism extends the attribute-based access control (ABAC) model. Business attributes areintroduced in the ABAC model as business constraints between entities. The proposed mechanism implementsa two-layer permission decision structure composed of the inherent attributes of access control entities and thebusiness attributes, which constitute the general permission decision algorithm based on logical calculation andthe business permission decision algorithm based on a bi-directional long short-term memory (BiLSTM) neuralnetwork, respectively. The general permission decision algorithm is used to implement accurate policy decisions,while the business permission decision algorithm implements fuzzy decisions based on the business constraints.The BiLSTM neural network is used to calculate the similarity of the business attributes to realize intelligent,adaptive, and efficient access control permission decisions. Through the two-layer permission decision structure,the complex and diverse big data access control management requirements can be satisfied by considering thesecurity and availability of resources. Experimental results show that the proposed mechanism is effective andreliable. In summary, it can efficiently support the secure sharing of big data resources. 展开更多
关键词 Big data access control data security BiLSTM
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Influence of Transportation Accessibility on Urban-rural Income Disparity and Its Spatial Heterogeneity
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作者 HUANG Xiaoyan KANG Chenchen +1 位作者 YIN Chun TANG Junqing 《Chinese Geographical Science》 SCIE CSCD 2024年第3期453-467,共15页
Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility ... Transportation accessibility has been treated as an important means of reducing the urban-rural income disparity.However,only a few studies have examined the effects of different types of transportation accessibility on urban-rural income disparity and their spatial heterogeneity.Based on data from 285 prefecture-level(and above)Chinese cities in 2000,2005,2010,2015,and 2020,this study uses spatial econometric models to examine how highway accessibility and railway accessibility influence the urban-rural income disparity and to identify their spatial heterogeneity.The result reveals that highway accessibility and railway accessibility have‘coreperiphery’ring-like circle structures.The urban-rural income disparity exhibits strong spatial clustering effects.Both highway accessibility and railway accessibility are negatively associated with urban-rural income disparity,and the former having a greater effect size.Moreover,there is a substitution effect between highway accessibility and railway accessibility in the whole sample.Furthermore,these associations differ in geographic regions.In the central region,highway accessibility is more important in reducing the urban-rural income disparity,but its effect is weakened with the increase of railway accessibility.In the western region,railway accessibility has a larger effect on narrowing the urban-rural income disparity,and this effect is strengthened by the increase of highway accessibility.We conclude that improving transportation accessibility is conducive to reducing the urban-rural income disparity but its effect is spatial heterogenetic.Highways and railways should be developed in a coordinated manner to promote an integrated transport network system. 展开更多
关键词 transport accessibility income gap regional divergence spatial heterogeneity urban and rural areas China
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