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The Interventional Capacity of Community Health Volunteers for Screening and Linkages of Non-Communicable Diseases in Nyeri County, Kenya
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作者 Kenneth Mugambi Jackline Nyaberi Elizabeth Echoka 《Open Journal of Preventive Medicine》 2024年第4期61-78,共18页
Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from... Non-communicable diseases (NCDs) account for 63% of mortalities. Approximately 80% of these NCD-related deaths occur in LMICs. A quasi-experimental study utilizing a non-equivalent pre-and post-test was conducted from May 2022 to March 2023 with 370 study participants. Multistage cluster and random sampling were used to select ten community units, and therefore, 150 CHVs were chosen for the control unit, and 150 were used to form the interventional group. Data was collected from the KOBO app. Six (6) homogenous FGDs comprised ten members, and 10 KII were conducted across study sites. Quantitative data was analyzed using SPSS version 28.0, and qualitative data was audio-recorded, transcribed, and analyzed via N-Vivo 12. The study shows that 59.3% of respondents have minimal information, and 92.7% (n = 139) have no clear understanding of NCDs, with a pre-intervention capacity of 48.8%. Independent sample t-test showed a significant difference in capacity from a pre-intervention average of 48.75 (SD ± 5.7)%, which increased to 68.28 (SD ± 7.6)%, p < 0.001. A well-designed community interventional model plays a pivotal role in grassroots healthcare delivery but requires optimization for NCD management. 展开更多
关键词 INTERVENTION Community Health Volunteers non-communicable Disease SCREENING Linkages
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Assessment of Barriers and Challenges to the Screening and Linkages of Non-Communicable Diseases by Community Health Volunteers in Nyeri County, Kenya
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作者 Kenneth Mugambi Jackline Nyaberi Elizabeth Echoka 《Open Journal of Preventive Medicine》 2024年第5期90-109,共20页
Non-communicable diseases (NCDs) are a significant global health challenge, contributing to 50% of worldwide morbidity and 63% of mortality. The burden is particularly substantial in low—and middle-income countries (... Non-communicable diseases (NCDs) are a significant global health challenge, contributing to 50% of worldwide morbidity and 63% of mortality. The burden is particularly substantial in low—and middle-income countries (LMICs), where 80% of NCD-related deaths occur. A quasi-experimental study addressed this challenge from May 2022 to March 2023. This study utilized a non-equivalent pre-and post-test design, with 300 participants in the quantitative and 70 in the qualitative. The study employed multistage cluster and random sampling to select ten community units, resulting in 150 community health volunteers (CHVs) in the control unit and 150 in the intervention group. Data collection was facilitated through the KOBO app. Qualitative data analysis involved six homogeneous focus group discussions (FGDs) and ten key informant interviews (KIIs), audio-recorded, transcribed, and analyzed using N-Vivo 12. Despite efforts to implement screening programs and improve linkages to care, significant barriers persist. This article reviews these barriers, drawing on current literature and empirical evidence. Key obstacles identified include limited awareness, inadequate healthcare infrastructure, cultural beliefs, financial constraints, fragmented healthcare systems, and challenges linking individuals to appropriate care services. The article explores strategies to overcome these barriers, emphasizing the importance of collaborative approaches involving stakeholders at various levels. Addressing these challenges aims to strengthen NCD screening and linkages to care, ultimately improving health outcomes for populations globally. Several recommendations emerge from the study’s findings and literature review. Raising awareness about NCDs and preventive measures is crucial and can be achieved through targeted health education campaigns and community outreach programs. Addressing healthcare infrastructure deficiencies, such as inadequate facilities and workforce shortages, is essential to ensure access to quality care. Cultural beliefs and practices also play a significant role in shaping health-seeking behavior. Engaging with local communities and incorporating cultural sensitivity into healthcare delivery can help bridge the gap between traditional beliefs and modern healthcare practices. Financial constraints pose a significant barrier to healthcare services, particularly in LMICs. Innovative financing mechanisms, such as health insurance schemes or subsidies, can help alleviate this burden and improve access to care. Furthermore, the fragmented nature of healthcare systems can hinder effective NCD management. Enhancing coordination and integration between primary care providers, specialists, and community health workers is essential to ensure seamless care delivery and patient follow-up. Finally, strengthening linkages between screening programs and care services is critical for the timely diagnosis and management of NCDs. This requires establishing robust referral systems and ensuring continuity of care for patients throughout their healthcare journey. In conclusion, addressing the multifaceted barriers to NCD screening and care linkage is essential for improving health outcomes globally. By implementing targeted interventions and fostering collaboration among stakeholders, progress can be made towards reducing the burden of NCDs and promoting population health. 展开更多
关键词 non-communicable Diseases Barriers CHALLENGES Healthcare Infrastructure AWARENESS Cultural Beliefs Financial Constraints
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Ultimately Bounded Output Feedback Control for Networked Nonlinear Systems With Unreliable Communication Channel: A Buffer-Aided Strategy
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作者 Yuhan Zhang Zidong Wang +2 位作者 Lei Zou Yun Chen Guoping Lu 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1566-1578,共13页
This paper concerns ultimately bounded output-feedback control problems for networked systems with unknown nonlinear dynamics. Sensor-to-observer signal transmission is facilitated over networks that has communication... This paper concerns ultimately bounded output-feedback control problems for networked systems with unknown nonlinear dynamics. Sensor-to-observer signal transmission is facilitated over networks that has communication constraints.These transmissions are carried out over an unreliable communication channel. In order to enhance the utilization rate of measurement data, a buffer-aided strategy is novelly employed to store historical measurements when communication networks are inaccessible. Using the neural network technique, a novel observer-based controller is introduced to address effects of signal transmission behaviors and unknown nonlinear dynamics.Through the application of stochastic analysis and Lyapunov stability, a joint framework is constructed for analyzing resultant system performance under the introduced controller. Subsequently, existence conditions for the desired output-feedback controller are delineated. The required parameters for the observerbased controller are then determined by resolving some specific matrix inequalities. Finally, a simulation example is showcased to confirm method efficacy. 展开更多
关键词 Buffer-aided strategy neural networks nonlinear control output-feedback control unreliable communication channel
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Distributed Fault Estimation for Nonlinear Systems With Sensor Saturation and Deception Attacks Using Stochastic Communication Protocols
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作者 Weiwei Sun Xinci Gao +1 位作者 Lusong Ding Xiangyu Chen 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第8期1865-1876,共12页
This paper is aimed at the distributed fault estimation issue associated with the potential loss of actuator efficiency for a type of discrete-time nonlinear systems with sensor saturation.For the distributed estimati... This paper is aimed at the distributed fault estimation issue associated with the potential loss of actuator efficiency for a type of discrete-time nonlinear systems with sensor saturation.For the distributed estimation structure under consideration,an estimation center is not necessary,and the estimator derives its information from itself and neighboring nodes,which fuses the state vector and the measurement vector.In an effort to cut down data conflicts in communication networks,the stochastic communication protocol(SCP)is employed so that the output signals from sensors can be selected.Additionally,a recursive security estimator scheme is created since attackers randomly inject malicious signals into the selected data.On this basis,sufficient conditions for a fault estimator with less conservatism are presented which ensure an upper bound of the estimation error covariance and the mean-square exponential boundedness of the estimating error.Finally,a numerical example is used to show the reliability and effectiveness of the considered distributed estimation algorithm. 展开更多
关键词 Actuator fault deception attacks distributed estimation sensor saturation stochastic communication protocol(SCP).
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Nonlinear Filtering With Sample-Based Approximation Under Constrained Communication:Progress, Insights and Trends
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作者 Weihao Song Zidong Wang +2 位作者 Zhongkui Li Jianan Wang Qing-Long Han 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第7期1539-1556,共18页
The nonlinear filtering problem has enduringly been an active research topic in both academia and industry due to its ever-growing theoretical importance and practical significance.The main objective of nonlinear filt... The nonlinear filtering problem has enduringly been an active research topic in both academia and industry due to its ever-growing theoretical importance and practical significance.The main objective of nonlinear filtering is to infer the states of a nonlinear dynamical system of interest based on the available noisy measurements. In recent years, the advance of network communication technology has not only popularized the networked systems with apparent advantages in terms of installation,cost and maintenance, but also brought about a series of challenges to the design of nonlinear filtering algorithms, among which the communication constraint has been recognized as a dominating concern. In this context, a great number of investigations have been launched towards the networked nonlinear filtering problem with communication constraints, and many samplebased nonlinear filters have been developed to deal with the highly nonlinear and/or non-Gaussian scenarios. The aim of this paper is to provide a timely survey about the recent advances on the sample-based networked nonlinear filtering problem from the perspective of communication constraints. More specifically, we first review three important families of sample-based filtering methods known as the unscented Kalman filter, particle filter,and maximum correntropy filter. Then, the latest developments are surveyed with stress on the topics regarding incomplete/imperfect information, limited resources and cyber security.Finally, several challenges and open problems are highlighted to shed some lights on the possible trends of future research in this realm. 展开更多
关键词 communication constraints maximum correntropy filter networked nonlinear filtering particle filter sample-based approximation unscented Kalman filter
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Research on the Performance of Non-Line-of-Sight Ultraviolet Communication in Rain and Fog Environment
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作者 Siqi Zhang 《Journal of Computer and Communications》 2024年第8期191-201,共11页
Wireless ultraviolet communication is a new type of communication mode. It refers to the transmission of information through the scattering of ultraviolet light by atmospheric particles and aerosol particles. The scat... Wireless ultraviolet communication is a new type of communication mode. It refers to the transmission of information through the scattering of ultraviolet light by atmospheric particles and aerosol particles. The scattering characteristics can enable the wireless ultraviolet communication system to transmit ultraviolet light signals in a non-line-of-sight manner, which overcomes the weakness that other free space optical communications must work in a line-of-sight manner. Based on the basic theory of scattering and absorption in atmospheric optics, taking the ultraviolet light with a wavelength of 266 nm as an example, this paper introduces the classical model of non-line-of-sight single-scattering coplanarity based on the ellipsoid coordinate system. The model is used to simulate and analyze the relationship between the geometric parameters such as transmission distance, transceiver elevation angle and transceiver half-angle and the received optical power per unit area. The performance of non-line-of-sight ultraviolet communication system in rain and fog environment is discussed respectively. The results show that the transmission quality of non-line-of-sight ultraviolet atmospheric propagation is greatly affected by the communication distance. As the distance increases, the received light power per unit area gradually decreases. In addition, increasing the emission elevation angle, the receiving elevation angle and the receiving half angle is an important way to improve the system performance. 展开更多
关键词 Ultraviolet Light Single Scattering Optical Scattering communication NLOS MATLAB
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Investigating College Students’ Diet and Physical Activity Behaviors Regarding Non-Communicable Diseases Prevention in China
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作者 Ling-Shen Hung Yueyuan Chen +2 位作者 Yuqi Huang Li-Ching Hung Meng-Te Hung 《Journal of Biosciences and Medicines》 CAS 2023年第2期302-310,共9页
We aimed to investigate if college students’ dietary and physical activity adhered to the Chinese Dietary Guidelines, the Composing Editorial Board of Physical Activity Guidelines, and WHO recommendation for NCDs pre... We aimed to investigate if college students’ dietary and physical activity adhered to the Chinese Dietary Guidelines, the Composing Editorial Board of Physical Activity Guidelines, and WHO recommendation for NCDs prevention. Methods: A 3-day (2 weekdays and 1 weekend day) 24-hour (24-HRs) dietary recall was conducted to record details of participants’ food consumption. One-way analysis of variance (ANOVA) was applied to examine the influence of the identified demographic variables (including BMI, gender, major, family monthly income, and place of household registration) on the 8 food groups’ consumption. We analyzed the effect of the various demographic variables on sodium intake by the student’s t-test. The questionnaire, International Physical Activity Questionnaire (IPAQ)-Short Form, was utilized to assess participants’ physical activity (PA) level. The Wilcoxon-Mann-Whitney was applied to analyze participants’ physical activity. Results: Our research indicated participants consumed much fewer fruits and vegetables and excessive meats on average for both males and females regarding NCDs prevention. Conclusion: Participants’ dietary intake did not comply with the Chinese Dietary Guide-lines recommendation for chronic diseases prevention. Nutrition knowledge and health education are needed for college students. . 展开更多
关键词 non-communicable Diseases Dietary Behavior Physical Activity College Students
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Clustering of Non-communicable Diseases Risk Factors in Healthy Adults Aged 35 Years and Older in Shenzhen,China 被引量:3
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作者 NI Wen Qing XU Jian +7 位作者 LIU Min LIU Xiao Li YANG Li Chen ZHUO Zhi Peng YUAN Xue Li SONG Jin Ping CHI Hong Shan BAI Ya Min 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2017年第9期661-666,共6页
We assessed the prevalence of non‐ communicable diseases(NCDs) risk factors with a focus on their clustering among healthy adults in Shenzhen, China. Data from the 2011 China Health and Nutrition Survey, comprising... We assessed the prevalence of non‐ communicable diseases(NCDs) risk factors with a focus on their clustering among healthy adults in Shenzhen, China. Data from the 2011 China Health and Nutrition Survey, comprising a regionally representative sample of 806 healthy adults aged 35 years or older, were obtained to determine the prevalence of five risk factors for NCDs. The prevalence of current smoking, central obesity, impaired fasting glucose, borderline hypertension, and borderline high total cholesterol was 19.97%, 28.29%, 4.47%, 10.55%, and 36.10%, respectively. A total 63.77% of participants had at least one risk factor. Upon examination of risk factor clustering, we observed that 7.57% of participants had at least three risk factors. Using this threshold as a cutoff, clustering of risk factors was associated with sex [odds ratio(OR) = 3.336, 95% confidence interval(CI): 1.782 to 6.246], physical activity(OR = 1.913, 95% CI: 1.009 to 3.628), and BMI(OR = 7.376, 95% CI: 3.812 to 14.270). The prevalence of risk factors for NCDs is fairly high among healthy adults in Shenzhen, with a clustering tendency. 展开更多
关键词 non‐communicable diseases Healthy adults PREVALENCE Risk factors
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Distributed Nash Equilibrium Seeking Strategies Under Quantized Communication 被引量:2
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作者 Maojiao Ye Qing-Long Han +2 位作者 Lei Ding Shengyuan Xu Guobiao Jia 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期103-112,共10页
This paper is concerned with distributed Nash equi librium seeking strategies under quantized communication. In the proposed seeking strategy, a projection operator is synthesized with a gradient search method to achi... This paper is concerned with distributed Nash equi librium seeking strategies under quantized communication. In the proposed seeking strategy, a projection operator is synthesized with a gradient search method to achieve the optimization o players' objective functions while restricting their actions within required non-empty, convex and compact domains. In addition, a leader-following consensus protocol, in which quantized informa tion flows are utilized, is employed for information sharing among players. More specifically, logarithmic quantizers and uniform quantizers are investigated under both undirected and connected communication graphs and strongly connected digraphs, respec tively. Through Lyapunov stability analysis, it is shown that play ers' actions can be steered to a neighborhood of the Nash equilib rium with logarithmic and uniform quantizers, and the quanti fied convergence error depends on the parameter of the quan tizer for both undirected and directed cases. A numerical exam ple is given to verify the theoretical results. 展开更多
关键词 CONSENSUS distributed Nash equilibrium seeking projected gradient play quantized communication
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Communication Resource-Efficient Vehicle Platooning Control With Various Spacing Policies 被引量:4
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作者 Xiaohua Ge Qing-Long Han +1 位作者 Xian-Ming Zhang Derui Ding 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第2期362-376,共15页
Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical cha... Platooning represents one of the key features that connected automated vehicles may possess as it allows multiple automated vehicles to be maneuvered cooperatively with small headways on roads. However, a critical challenge in accomplishing automated vehicle platoons is to deal with the effects of intermittent and sporadic vehicle-to-vehicle data transmissions caused by limited wireless communication resources. This paper addresses the co-design problem of dynamic event-triggered communication scheduling and cooperative adaptive cruise control for a convoy of automated vehicles with diverse spacing policies. The central aim is to achieve automated vehicle platooning under various gap references with desired platoon stability and spacing performance requirements, while simultaneously improving communication efficiency. Toward this aim, a dynamic event-triggered scheduling mechanism is developed such that the intervehicle data transmissions are scheduled dynamically and efficiently over time. Then, a tractable co-design criterion on the existence of both the admissible event-driven cooperative adaptive cruise control law and the desired scheduling mechanism is derived. Finally, comparative simulation results are presented to substantiate the effectiveness and merits of the obtained results. 展开更多
关键词 Automated vehicles constant time headway spacing constant spacing cooperative adaptive cruise control event-triggered communication vehicle platooning
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Falcon Optimization Algorithm-Based Energy Efficient Communication Protocol for Cluster-Based Vehicular Networks 被引量:1
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作者 Youseef Alotaibi B.Rajasekar +1 位作者 R.Jayalakshmi Surendran Rajendran 《Computers, Materials & Continua》 SCIE EI 2024年第3期4243-4262,共20页
Rapid development in Information Technology(IT)has allowed several novel application regions like large outdoor vehicular networks for Vehicle-to-Vehicle(V2V)transmission.Vehicular networks give a safe and more effect... Rapid development in Information Technology(IT)has allowed several novel application regions like large outdoor vehicular networks for Vehicle-to-Vehicle(V2V)transmission.Vehicular networks give a safe and more effective driving experience by presenting time-sensitive and location-aware data.The communication occurs directly between V2V and Base Station(BS)units such as the Road Side Unit(RSU),named as a Vehicle to Infrastructure(V2I).However,the frequent topology alterations in VANETs generate several problems with data transmission as the vehicle velocity differs with time.Therefore,the scheme of an effectual routing protocol for reliable and stable communications is significant.Current research demonstrates that clustering is an intelligent method for effectual routing in a mobile environment.Therefore,this article presents a Falcon Optimization Algorithm-based Energy Efficient Communication Protocol for Cluster-based Routing(FOA-EECPCR)technique in VANETS.The FOA-EECPCR technique intends to group the vehicles and determine the shortest route in the VANET.To accomplish this,the FOA-EECPCR technique initially clusters the vehicles using FOA with fitness functions comprising energy,distance,and trust level.For the routing process,the Sparrow Search Algorithm(SSA)is derived with a fitness function that encompasses two variables,namely,energy and distance.A series of experiments have been conducted to exhibit the enhanced performance of the FOA-EECPCR method.The experimental outcomes demonstrate the enhanced performance of the FOA-EECPCR approach over other current methods. 展开更多
关键词 Vehicular networks communication protocol CLUSTERING falcon optimization algorithm ROUTING
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Cooperative User-Scheduling and Resource Allocation Optimization for Intelligent Reflecting Surface Enhanced LEO Satellite Communication 被引量:1
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作者 Meng Meng Bo Hu +1 位作者 Shanzhi Chen Jianyin Zhang 《China Communications》 SCIE CSCD 2024年第2期227-244,共18页
Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO sate... Lower Earth Orbit(LEO) satellite becomes an important part of complementing terrestrial communication due to its lower orbital altitude and smaller propagation delay than Geostationary satellite. However, the LEO satellite communication system cannot meet the requirements of users when the satellite-terrestrial link is blocked by obstacles. To solve this problem, we introduce Intelligent reflect surface(IRS) for improving the achievable rate of terrestrial users in LEO satellite communication. We investigated joint IRS scheduling, user scheduling, power and bandwidth allocation(JIRPB) optimization algorithm for improving LEO satellite system throughput.The optimization problem of joint user scheduling and resource allocation is formulated as a non-convex optimization problem. To cope with this problem, the nonconvex optimization problem is divided into resource allocation optimization sub-problem and scheduling optimization sub-problem firstly. Second, we optimize the resource allocation sub-problem via alternating direction multiplier method(ADMM) and scheduling sub-problem via Lagrangian dual method repeatedly.Third, we prove that the proposed resource allocation algorithm based ADMM approaches sublinear convergence theoretically. Finally, we demonstrate that the proposed JIRPB optimization algorithm improves the LEO satellite communication system throughput. 展开更多
关键词 convex optimization intelligent reflecting surface LEO satellite communication OFDM
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Impact of sepsis and non-communicable diseases on prognostic models to predict the outcome of hospitalized chronic liver disease patients 被引量:2
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作者 Fakhar Ali Qazi Arisar Shahab Abid +1 位作者 Preet Ayoub Shaikh Safia Awan 《World Journal of Hepatology》 CAS 2018年第12期944-955,共12页
AIM To evaluate the impact of sepsis and non-communicable diseases(NCDs) on the outcome of decompensated chronic liver disease(CLD) patients.METHODSIn this cross-sectional study, medical records of patients with CLD a... AIM To evaluate the impact of sepsis and non-communicable diseases(NCDs) on the outcome of decompensated chronic liver disease(CLD) patients.METHODSIn this cross-sectional study, medical records of patients with CLD admitted to the Gastroenterology unit at the Aga Khan University Hospital were reviewed.Patients older than 18 years with decompensation of CLD(i.e., jaundice, ascites,encephalopathy, and/or upper gastrointestinal bleed) as the primary reason for admission were included, while those who were admitted for reasons other than decompensation of CLD were excluded. Each patient was followed for 6 wk after index admission to assess mortality, prolonged hospital stay(> 5 d), and early readmission(within 7 d).RESULTS A total of 399 patients were enrolled. The mean age was 54.3 ± 11.7 years and64.6%(n = 258) were male. Six-week mortality was 13%(n = 52). Prolonged hospital stay and readmission were present in 18%(n = 72) and 7%(n = 28) of patients, respectively. NCDs were found in 47.4%(n = 189) of patients. Acute kidney injury, sepsis, and non-ST elevation myocardial infarction were found in41%(n = 165), 17.5%(n = 70), and 1.75%(n = 7) of patients, respectively. Upon multivariate analysis, acute kidney injury, non-ST elevation myocardial infarction, sepsis, and coagulopathy were found to be statistically significant predictors of mortality. While chronic kidney disease(CKD), low albumin, and high Model for End-Stage Liver Disease(MELD)-Na score were found to be statistically significant predictors of morbidity. Addition of sepsis in conventionalMELD score predicted mortality even better than MELD-Na(area under receiver operating characteristic: 0.735 vs 0.686; P < 0.001). Among NCDs, CKD was found to increase morbidity independently.CONCLUSION Addition of sepsis improved the predictability of MELD score as a prognostic marker for mortality in patients with CLD. Presence of CKD increases the morbidity of patients with CLD. 展开更多
关键词 Chronic liver disease MORTALITY MORBIDITY PROGNOSTIC factors noncommunicable diseases SEPSIS
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Cooperative UAV search strategy based on DMPC-AACO algorithm in restricted communication scenarios 被引量:1
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作者 Shiyuan Chai Zhen Yang +3 位作者 Jichuan Huang Xiaoyang Li Yiyang Zhao Deyun Zhou 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2024年第1期295-311,共17页
Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research pr... Improvement of integrated battlefield situational awareness in complex environments involving dynamic factors such as restricted communications and electromagnetic interference(EMI)has become a contentious research problem.In certain mission environments,due to the impact of many interference sources on real-time communication or mission requirements such as the need to implement communication regulations,the mission stages are represented as a dynamic combination of several communication-available and communication-unavailable stages.Furthermore,the data interaction between unmanned aerial vehicles(UAVs)can only be performed in specific communication-available stages.Traditional cooperative search algorithms cannot handle such situations well.To solve this problem,this study constructed a distributed model predictive control(DMPC)architecture for a collaborative control of UAVs and used the Voronoi diagram generation method to re-plan the search areas of all UAVs in real time to avoid repetition of search areas and UAV collisions while improving the search efficiency and safety factor.An attention mechanism ant-colony optimization(AACO)algorithm is proposed for UAV search-control decision planning.The search strategy is adaptively updated by introducing an attention mechanism for regular instruction information,a priori information,and emergent information of the mission to satisfy different search expectations to the maximum extent.Simulation results show that the proposed algorithm achieves better search performance than traditional algorithms in restricted communication constraint scenarios. 展开更多
关键词 Unmanned aerial vehicles(UAV) Cooperative search Restricted communication Mission planning DMPC-AACO
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Robust or nonrobust: On MC-DS-CDMA acquisition in LEO satellite communications
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作者 Entong Meng Xiangyuan Bu +2 位作者 Jihong Yu Jianping An Xuanhe Yang 《Digital Communications and Networks》 SCIE CSCD 2023年第4期896-905,共10页
Low Earth Orbit(LEO)satellite communications can provide global coverage in the sixth generation communication(6G)networks.To combat the strong Partial Band Interferences(PBIs)and multipath fading in LEO satellite com... Low Earth Orbit(LEO)satellite communications can provide global coverage in the sixth generation communication(6G)networks.To combat the strong Partial Band Interferences(PBIs)and multipath fading in LEO satellite communication systems,the Multicarrier Direct Sequence Code Division Multiple Access(MC-DS-CDMA)technique is a promising alternative to the traditional Single-carrier Direct Sequence Code Division Multiple Access(SC-DS-CDMA)system for its advantages of high bandwidth efficiency,superior interference rejection capability,and low complexity of parallel signal processing.However,limited studies have been conducted on the performance analysis of MC-DS-CDMA acquisition systems in the presence of a large Doppler shift,a unique characteristic of LEO satellite communications.To bridge this gap,we investigate the performance of MC-DS-CDMA systems with two-dimensional acquisition and noncoherent equal gain combining over Rician fading channel in the presence of the Doppler shift and PBIs.The performance metrics are detection probability and Mean Square Error(MSE)of the Doppler factor and delay.Specifically,we derive the closed-form expressions for the MSE and the Probability Density Function(PDF)of the acquisition decision variable and obtain the detection probability.We conduct extensive numerical experiments to verify the theoretical analysis and performance gain of MC-DSCDMA over the SC-DS-CDMA.The results show that MC-DS-CDMA with two-dimensional acquisition is more robust to multipath Rician fading than SC-DS-CDMA.Moreover,MC-DS-CDMA outperforms SC-DS-CDMA regarding the detection probability and MSE when combating the strong PBIs. 展开更多
关键词 Satellite communications MC-DS-CDMA Acquisition performance Rician fading channel Partial band interference
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A survey on semantic communications:Technologies,solutions,applications and challenges
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作者 Yating Liu Xiaojie Wang +3 位作者 Zhaolong Ning MengChu Zhou Lei Guo Behrouz Jedari 《Digital Communications and Networks》 SCIE CSCD 2024年第3期528-545,共18页
Semantic Communication(SC)has emerged as a novel communication paradigm that provides a receiver with meaningful information extracted from the source to maximize information transmission throughput in wireless networ... Semantic Communication(SC)has emerged as a novel communication paradigm that provides a receiver with meaningful information extracted from the source to maximize information transmission throughput in wireless networks,beyond the theoretical capacity limit.Despite the extensive research on SC,there is a lack of comprehensive survey on technologies,solutions,applications,and challenges for SC.In this article,the development of SC is first reviewed and its characteristics,architecture,and advantages are summarized.Next,key technologies such as semantic extraction,semantic encoding,and semantic segmentation are discussed and their corresponding solutions in terms of efficiency,robustness,adaptability,and reliability are summarized.Applications of SC to UAV communication,remote image sensing and fusion,intelligent transportation,and healthcare are also presented and their strategies are summarized.Finally,some challenges and future research directions are presented to provide guidance for further research of SC. 展开更多
关键词 Semantic communication Semantic coding Semantic extraction Semantic communication framework Semantic communication applications
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Building Semantic Communication System via Molecules:An End-to-End Training Approach
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作者 Cheng Yukun Chen Wei Ai Bo 《China Communications》 SCIE CSCD 2024年第7期113-124,共12页
The concept of semantic communication provides a novel approach for applications in scenarios with limited communication resources.In this paper,we propose an end-to-end(E2E)semantic molecular communication system,aim... The concept of semantic communication provides a novel approach for applications in scenarios with limited communication resources.In this paper,we propose an end-to-end(E2E)semantic molecular communication system,aiming to enhance the efficiency of molecular communication systems by reducing the transmitted information.Specifically,following the joint source channel coding paradigm,the network is designed to encode the task-relevant information into the concentration of the information molecules,which is robust to the degradation of the molecular communication channel.Furthermore,we propose a channel network to enable the E2E learning over the non-differentiable molecular channel.Experimental results demonstrate the superior performance of the semantic molecular communication system over the conventional methods in classification tasks. 展开更多
关键词 deep learning end-to-end learning molecular communication semantic communication
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Prevalence of Tobacco Use and Associated Factors among Adults in Benin in 2015: Results of the National Survey of Non-Communicable Disease Risk Factors
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作者 Alexandrine Houinato Roch Christian Johnson +3 位作者 Alphonse Kpozehouen Fernand Guedou Christophe Houssou Dismand S. Houinato 《Open Journal of Epidemiology》 2018年第3期130-144,共15页
Introduction: Tobacco use and exposure to tobacco smoke are one of the most preventable causes of death and disability worldwide. The risk is even higher among daily tobacco consumers. The World Health Organization (W... Introduction: Tobacco use and exposure to tobacco smoke are one of the most preventable causes of death and disability worldwide. The risk is even higher among daily tobacco consumers. The World Health Organization (WHO) recommended that surveillance of major risk factors for non- communicable diseases (NCDs), such as smoking, be imperative to predicting the future burden of NCDs, identifying adequate interventions to decrease future burden and monitor trends. In 2015, a survey on NCD risk factors was conducted in Benin to estimate the prevalence of major NCD risk factors. We analyzed the data from this survey to estimate the prevalence and risk factors associated with daily tobacco consumption in Benin. Methods: A nationwide representative sample of the population was constituted in the 12 departments of Benin. The WHO STEPS wise tool was used to collect data on behavioral and demographic characteristics, including daily tobacco consumption. Tobacco consumption was subdivided into three categories: The daily consumption of tobacco, the daily consumption of smoked tobacco and non-smoked tobacco. Multivariate analysis through the weighted logistic regression was used to identify potential factors associated with daily consumption of tobacco. Results: Over the 5.126 surveyed subjects, 7.49% were daily tobacco consumers, with 3.85% being daily users of smoked tobacco and 4.36% being daily consumers of non-smoked tobacco. Men were more likely to be daily consumers of tobacco compared to women (OR = 7.42;95%CI = [4.98;11.06]). Compared to respondents aged 18 to 24, those aged 45 to 54 were five times more likely to consume tobacco (OR = 5.58;95%IC = [2.71;11.47]). Respondents residing in the departments of Atacora, Couffo and Borgou were respectively 4.28 times, 3.93 times and 2.63 times more likely to consume tobacco compared to those residing in the department of Alibori. Respondents with no education were more likely to consume tobacco daily compared to respondents who had finished high school or were in university (OR = 3.73;95%CI = [1.36;10.23]. Respondents who were overweight were less likely to be daily users of tobacco compared to people with normal weight status (OR = 0.57;95%CI = [0.34;0.96]). Conclusion: There is a relatively high prevalence of smoking in Benin, where one out of 8 people, consumes tobacco products daily. Being elderly, male, having no formal education, residing in Atacora, Borgou or Couffo were significantly associated with daily smoking. Prevention actions should thus target those sub-groups of the population. 展开更多
关键词 TOBACCO non communicable Diseases STEP WISE BENIN
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Reconfigurable MIMO-based self-powered battery-less light communication system
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作者 Jose Ilton De Oliveira Filho Abderrahmen Trichili +3 位作者 Omar Alkhazragi Mohamed-Slim Alouini Boon S.Ooi Khaled Nabil Salama 《Light(Science & Applications)》 SCIE EI CSCD 2024年第10期2300-2311,共12页
Simultaneous lightwave information and power transfer (SLIPT), co-existing with optical wireless communication,holds an enormous potential to provide continuous charging to remote Internet of Things (IoT) devices whil... Simultaneous lightwave information and power transfer (SLIPT), co-existing with optical wireless communication,holds an enormous potential to provide continuous charging to remote Internet of Things (IoT) devices while ensuringconnectivity. Combining SLIPT with an omnidirectional receiver, we can leverage a higher power budget whilemaintaining a stable connection, a major challenge for optical wireless communication systems. Here, we design amultiplexed SLIPT-based system comprising an array of photodetectors (PDs) arranged in a 3 × 3 configuration. Thesystem enables decoding information from multiple light beams while simultaneously harvesting energy. The PDs canswiftly switch between photoconductive and photovoltaic modes to maximize information transfer rates and provideon-demand energy harvesting. Additionally, we investigated the ability to decode information and harvest energywith a particular quadrant set of PDs from the array, allowing beam tracking and spatial diversity. The design wasexplored in a smaller version for higher data rates and a bigger one for higher power harvesting. We report a selfpoweringdevice that can achieve a gross data rate of 25.7 Mbps from a single-input single-output (SISO) and an 85.2Mbps net data rate in a multiple-input multiple-output (MIMO) configuration. Under a standard AMT1.5 illumination,the device can harvest up to 87.33 mW, around twice the power needed to maintain the entire system. Our workpaves the way for deploying autonomous IoT devices in harsh environments and their potential use in spaceapplications. 展开更多
关键词 communicATION MIMO system
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Recent Developments in Authentication Schemes Used in Machine-Type Communication Devices in Machine-to-Machine Communication: Issues and Challenges
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作者 Shafi Ullah Sibghat Ullah Bazai +9 位作者 Mohammad Imran Qazi Mudassar Ilyas Abid Mehmood Muhammad Asim Saleem Muhmmad Aasim Rafique Arsalan Haider Ilyas Khan Sajid Iqbal Yonis Gulzar Kauser Hameed 《Computers, Materials & Continua》 SCIE EI 2024年第4期93-115,共23页
Machine-to-machine (M2M) communication plays a fundamental role in autonomous IoT (Internet of Things)-based infrastructure, a vital part of the fourth industrial revolution. Machine-type communication devices(MTCDs) ... Machine-to-machine (M2M) communication plays a fundamental role in autonomous IoT (Internet of Things)-based infrastructure, a vital part of the fourth industrial revolution. Machine-type communication devices(MTCDs) regularly share extensive data without human intervention while making all types of decisions. Thesedecisions may involve controlling sensitive ventilation systems maintaining uniform temperature, live heartbeatmonitoring, and several different alert systems. Many of these devices simultaneously share data to form anautomated system. The data shared between machine-type communication devices (MTCDs) is prone to risk dueto limited computational power, internal memory, and energy capacity. Therefore, securing the data and devicesbecomes challenging due to factors such as dynamic operational environments, remoteness, harsh conditions,and areas where human physical access is difficult. One of the crucial parts of securing MTCDs and data isauthentication, where each devicemust be verified before data transmission. SeveralM2Mauthentication schemeshave been proposed in the literature, however, the literature lacks a comprehensive overview of current M2Mauthentication techniques and the challenges associated with them. To utilize a suitable authentication schemefor specific scenarios, it is important to understand the challenges associated with it. Therefore, this article fillsthis gap by reviewing the state-of-the-art research on authentication schemes in MTCDs specifically concerningapplication categories, security provisions, and performance efficiency. 展开更多
关键词 AUTHENTICATION cyber security internet of things machine-type communication devices machine-to-machine communication
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