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Pixel-by-Pixel Analysis of Soil and Leaf Coverage in Purslane: A CIELAB Approach
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作者 Abel Quevedo-Nolasco Graciano-Javier Aguado-Rodríguez +1 位作者 Francisco-Marcelo Lara-Viveros Nadia Landero-Valenzuela 《Agricultural Sciences》 2025年第2期227-239,共13页
This study utilized a computer application developed in Visual StudioTM using C# to extract pixel samples (RGB) from multiple images (26 images obtained from August 20, 2024, to September 22, 2024), of a purslane pot ... This study utilized a computer application developed in Visual StudioTM using C# to extract pixel samples (RGB) from multiple images (26 images obtained from August 20, 2024, to September 22, 2024), of a purslane pot taken from a top-down perspective at a distance of 30 cm. These samples were projected into the CIELAB color space, and the extracted pixels were plotted on the a*b* plane, excluding the luminance value. A polygon was then drawn around all the plotted pixels, defining the color to be identified. Subsequently, the application analyzed another image to determine the number of pixels within the polygon. These identified pixels were transformed to white, and the percentage of these pixels relative to the total number of pixels in the image was calculated. This process yielded percentages for brown (soil), green (leaf cover), and pink (stem color). A single polygon was sufficient to accurately identify the green and brown colors in the images. However, due to varying lighting conditions, customized polygons were necessary for each image to accurately identify the stem color. To validate the green polygon’s accuracy in identifying purslane leaves, all leaves in the image were digitized in AutoCADTM, and the green area was compared to the total image area to obtain the observed green percentage. The green percentage obtained with the polygon was then compared to the observed green percentage, resulting in an R2 value of 0.8431. Similarly, for the brown color, an R2 value of 0.9305 was found. The stem color was not subjected to this validation due to the necessity of multiple polygons. The R2 values were derived from percentage data obtained by analyzing the total pixels in the images. When sampling to estimate the proportion and analyzing only the suggested sample size of pixels, R2 values of 0.93049 for brown and 0.8088 for green were obtained. The average analysis time to determine the brown soil percentage using the polygon (BP) for 26 images with an average size of 1070 × 1210 pixels was 44 seconds. In contrast, sampling to estimate the proportion reduced the analysis time to 0.9 seconds for the same number of images. This indicates that significant time savings can be achieved while obtaining similar results. 展开更多
关键词 Automated Color Identification C# Application Color Space Soil Color Identification Leaf coverage
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Evaluating the vaccination coverage and timeliness of childhood vaccination among Indigenous children in Peninsular Malaysia:Findings from the 2022 Orang Asli Health Survey
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作者 Nor’Ain Ab Wahab S Maria Awaluddin +3 位作者 Norliza Shamsuddin Nurul Haniyah Rosslan Muhammad Azri Adam Ahmad Adnan Noor Ani Ahmad 《Asian Pacific Journal of Tropical Medicine》 2025年第3期139-146,共8页
Objective:To assess the complete vaccination coverage and timeliness of childhood vaccinations among Indigenous children in Peninsular Malaysia.Methods:The study utilized data from the 2022 Orang Asli Health Survey,a ... Objective:To assess the complete vaccination coverage and timeliness of childhood vaccinations among Indigenous children in Peninsular Malaysia.Methods:The study utilized data from the 2022 Orang Asli Health Survey,a cross-sectional survey conducted among a representative sample of Orang Asli in Peninsular Malaysia.A total of 68 villages were randomly selected from a pool of 853 villages,encompassing diverse geographic and sociodemographic contexts with a total of 15950 respondents Orang Asli successfully interviewed.However,this study only utilized data from surveyed children aged 12 to 59 months with a total of 1551 children included.Validated structured questionnaires were used to collect sociodemographic data and health status,with nurses verifying vaccination records.Children who received all nine primary vaccinations were defined as having complete vaccination while those who received vaccine within the recommended time were defined as having timely vaccination.Data analysis was conducted using IBM SPSS version 25.0,focusing on descriptive analyses of children's vaccination status.Results:The prevalence of overall complete vaccination among Indigenous children was 87.7%,while timely vaccination was only 40.3%.The prevalence of complete vaccination for Bacillus Calmette-Guérin(BCG),the first dose of hepatitis B,three doses of DTaP-IPV-Hib,and measles,mumps,and rubella(MMR)was above 95.0%,except for the second and third doses of hepatitis B.The prevalence of timely vaccination ranged from above 95.0%for vaccines given at birth,gradually decreasing with increasing age to 57.5%for the first dose of MMR.Moreover,the completion rates for three doses of DtaP-IPV-Hib and the initial dose of MMR surpassed 90%among Indigenous children aged 12-23 months,yet the timeliness remained at a moderate level.Conclusions:While the overall complete vaccination coverage among Indigenous children in Malaysia is relatively high,there are concerning disparities in the timeliness of vaccination,particularly as children age. 展开更多
关键词 Childhood vaccination coverage Orang Asli Indigenous TIMELINESS Age-appropriate vaccinations Peninsular Malaysia
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Impact of vegetation coverage and configuration on urban temperatures:a comparative study of 31 provincial capital cities in China
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作者 Chengcong Wang Zhibin Ren +6 位作者 Peng Zhang Yujie Guo Shengyang Hong Wenhai Hong Xinyu Wang Ruoxuan Geng Fanyue Meng 《Journal of Forestry Research》 2025年第1期163-177,共15页
Urban vegetation plays a crucial role in regulating temperatures and heat waves in urban areas.However,the influence of vegetation coverage and its configuration on surface temperatures in different climate zones at a... Urban vegetation plays a crucial role in regulating temperatures and heat waves in urban areas.However,the influence of vegetation coverage and its configuration on surface temperatures in different climate zones at a national scale is unclear.To address this,we utilized high-resolution data to detect spatial patterns for 31 provincial capital cities in China.We integrated day and night surface temperatures to determine the influence of vegetative coverage and configuration on urban temperatures across different climate zones and city sizes.Our study revealed that a subtropical monsoon climate and medium-sized cities had the highest vegetative coverage and shape complexity.The best connectivity and agglomeration of vegetation were found in a temperate monsoon climate and large cities.In contrast,small cities,especially those under a temperate continental climate,had low vegetation coverage,high fragmentation,and weak agglomeration and connectivity.In addition,vegetative coverage had a negative impact on daytime surface temperatures,especially in large cities in a subtropical monsoon climate.However,an increase in vegetation coverage could result in warming at night in small cities in temperate continental climates.Although urban vegetation configuration also contributed to moderating surface temperatures,especially at night,they did not surpass the influence of vegetation coverage.The effect on nighttime temperatures of the configuration of vegetation increased by 3–6%relative to that of daytime temperatures,especially in large cities in a temperate monsoon climate.The contribution vegetation coverage and configuration interaction to cooling efficiency decreased at night,especially in medium-sized cities in a temperate continental climate by 3–5%.In addition,this study identified several moderating effects of natural and social factors on the relationship between urban vegetation coverage and surface temperatures.High duration of sunshine,low humidity and high wind speed significantly enhanced the negative impact of vegetation coverage on surface temperatures.In addition,the moderating effect of vegetation coverage was more pronounced in low population density cities and high gross domestic product.This study enhances understanding of the ecological functions of urban vegetation and provides a valuable scientific basis and strategic recommendations for optimizing urban vegetation and improving urban environmental quality. 展开更多
关键词 Daytime and nighttime urban temperatures Landscape patterns Moderating effect Urban vegetation coverage
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Understanding the C-C coupling mechanism in electrochemical CO reduction at low CO coverage:Dynamic change in site preference matters
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作者 Zhe Chen Tao Wang 《Chinese Journal of Catalysis》 2025年第2期193-202,共10页
A thoroughly mechanistic understanding of the electrochemical CO reduction reaction(eCORR)at the interface is significant for guiding the design of high-performance electrocatalysts.However,unintentionally ignored fac... A thoroughly mechanistic understanding of the electrochemical CO reduction reaction(eCORR)at the interface is significant for guiding the design of high-performance electrocatalysts.However,unintentionally ignored factors or unreasonable settings during mechanism simulations will result in false positive results between theory and experiment.Herein,we computationally identified the dynamic site preference change of CO adsorption with potentials on Cu(100),which was a previously unnoticed factor but significant to potential-dependent mechanistic studies.Combined with the different lateral interactions among adsorbates,we proposed a new C–C coupling mechanism on Cu(100),better explaining the product distribution at different potentials in experimental eCORR.At low potentials(from–0.4 to–0.6 V_(RHE)),the CO forms dominant adsorption on the bridge site,which couples with another attractively aggregated CO to form a C–C bond.At medium potentials(from–0.6 to–0.8 VRHE),the hollow-bound CO becomes dominant but tends to isolate with another adsorbate due to the repulsion,thereby blocking the coupling process.At high potentials(above–0.8 VRHE),the CHO intermediate is produced from the electroreduction of hollow-CO and favors the attraction with another bridge-CO to trigger C–C coupling,making CHO the major common intermediate for C–C bond formation and methane production.We anticipate that our computationally identified dynamic change in site preference of adsorbates with potentials will bring new opportunities for a better understanding of the potential-dependent electrochemical processes. 展开更多
关键词 Electrochemical CO reduction reaction Lowco coverage Dynamic site-preference Potential-dependent C-C coupling Constant-potential density functional theory
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Deployment optimization for target perpetual coverage in energy harvesting wireless sensor network 被引量:2
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作者 Zhenkun Jin Yixuan Geng +4 位作者 Chenlu Zhu Yunzhi Xia Xianjun Deng Lingzhi Yi Xianlan Wang 《Digital Communications and Networks》 SCIE CSCD 2024年第2期498-508,共11页
Energy limitation of traditional Wireless Sensor Networks(WSNs)greatly confines the network lifetime due to generating and processing massive sensing data with a limited battery.The energy harvesting WSN is a novel ne... Energy limitation of traditional Wireless Sensor Networks(WSNs)greatly confines the network lifetime due to generating and processing massive sensing data with a limited battery.The energy harvesting WSN is a novel network architecture to address the limitation of traditional WSN.However,existing coverage and deployment schemes neglect the environmental correlation of sensor nodes and external energy with respect to physical space.Comprehensively considering the spatial correlation of the environment and the uneven distribution of energy in energy harvesting WSN,we investigate how to deploy a collection of sensor nodes to save the deployment cost while ensuring the target perpetual coverage.The Confident Information Coverage(CIC)model is adopted to formulate the CIC Minimum Deployment Cost Target Perpetual Coverage(CICMTP)problem to minimize the deployed sensor nodes.As the CICMTP is NP-hard,we devise two approximation algorithms named Local Greedy Threshold Algorithm based on CIC(LGTA-CIC)and Overall Greedy Search Algorithm based on CIC(OGSA-CIC).The LGTA-CIC has a low time complexity and the OGSA-CIC has a better approximation rate.Extensive simulation results demonstrate that the OGSA-CIC is able to achieve lower deployment cost and the performance of the proposed algorithms outperforms GRNP,TPNP and EENP algorithms. 展开更多
关键词 Energy harvesting WSN Deployment optimization Confident information coverage(CIC) Target perpetual coverage
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Coverage and Factors Associated with Acceptance and Satisfaction of Seasonal Malaria Chemoprevention in Six Health Zones in Benin
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作者 Cyriaque Affoukou Georgia Damien +8 位作者 Thibaud Lègba Olarewadjou Richard Biaou Boni Géraud Padonou Rock Aïkpon William Houndjo Camille Houetohossou Elysé Sohizoun Aurore Ogouyemi Badirou Aguèmon 《Open Journal of Preventive Medicine》 2024年第3期49-60,共12页
Introduction: Seasonal malaria chemoprevention (SMC) was adopted in 2019 in two health zones in Benin where malaria transmission is very high. Positive results led to the extension of the intervention to other zones w... Introduction: Seasonal malaria chemoprevention (SMC) was adopted in 2019 in two health zones in Benin where malaria transmission is very high. Positive results led to the extension of the intervention to other zones with additional financial support. Annual SMC campaigns from 2021 to 2023 were carried out in all six health zones in the Atacora and Alibori departments. In five years of implementation, various approaches have been developed on the basis of a communication plan facilitating buy-in and acceptance by all stakeholders. The aim of this study was to assess the effective coverage and acceptance of the SMC by their beneficiary populations in 2023. Methods: It was a cross-sectional study with an analytical focus. Data collection took place from November 30 to December 13, 2023. The study population consisted of children under 5 years of age residing in the departments of Atacora and Alibori in northern Benin. A total of 3573 children under 5 years of age were included in the study, and their parents or guardians were interviewed. Results: During the 2023 campaign, 87.7% of targets were reached by SMC administration and 100.00% of children had received at least one dose of SMC by the fourth visit. Effective therapeutic coverage of SMC was 70.55%, with 99.60% in BNK, 69.40% in KGS, 16.20% in MK, 56.10% in 2KP, 92.40% in NBT and 89.60% in TMC. This coverage was statistically related to child and respondent ages (p Conclusion: SMC is a strategy accepted by the population, and the main reasons for non-participation in SMC were dominated by the absence of mothers or babysitters when the agents visited. 展开更多
关键词 coverage ACCEPTANCE SMC BENIN
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Models to Simulate Effective Coverage of Fire Station Based on Real-Time Travel Times
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作者 Sicheng Zhu Dingli Liu +2 位作者 Weijun Liu Ying Li Tian Zhou 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第4期483-513,共31页
In recent years,frequent fire disasters have led to enormous damage in China.Effective firefighting rescues can minimize the losses caused by fires.During the rescue processes,the travel time of fire trucks can be sev... In recent years,frequent fire disasters have led to enormous damage in China.Effective firefighting rescues can minimize the losses caused by fires.During the rescue processes,the travel time of fire trucks can be severely affected by traffic conditions,changing the effective coverage of fire stations.However,it is still challenging to determine the effective coverage of fire stations considering dynamic traffic conditions.This paper addresses this issue by combining the traveling time calculationmodelwith the effective coverage simulationmodel.In addition,it proposes a new index of total effective coverage area(TECA)based on the time-weighted average of the effective coverage area(ECA)to evaluate the urban fire services.It also selects China as the case study to validate the feasibility of the models,a fire station(FS-JX)in Changsha.FS-JX station and its surrounding 9,117 fire risk points are selected as the fire service supply and demand points,respectively.A total of 196 simulation scenarios throughout a consecutiveweek are analyzed.Eventually,1,933,815 sets of valid sample data are obtained.The results showed that the TECA of FS-JX is 3.27 km^(2),which is far below the standard requirement of 7.00 km^(2) due to the traffic conditions.The visualization results showed that three rivers around FS-JX interrupt the continuity of its effective coverage.The proposed method can provide data support to optimize the locations of fire stations by accurately and dynamically determining the effective coverage of fire stations. 展开更多
关键词 Fire services fire station effective coverage real-time traffic SIMULATION
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Hepatitis B Vaccination Coverage among University Students in Sub-Saharan Africa: Systematic Review and Meta Analysis
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作者 Lebem Togtoga Abdourahmane Ndong +2 位作者 Saidou Bah Papa Djibril Ndoye Khadim Niang 《Journal of Biosciences and Medicines》 2024年第10期45-58,共14页
Introduction: Hepatitis B is an infectious disease that remains a real public health problem in Africa. Students represent a group at risk for this disease. The objective of this study was to estimate the hepatitis B ... Introduction: Hepatitis B is an infectious disease that remains a real public health problem in Africa. Students represent a group at risk for this disease. The objective of this study was to estimate the hepatitis B vaccination coverage rate among students in sub-Saharan Africa. Methods: A systematic search of databases (PubMed, AJOL) and a manual search of Google Scholar was conducted to retrieve all published studies reporting hepatitis B vaccination coverage among students in sub-Saharan Africa. The pooled coverage rate was estimated with a 95% confidence interval (CI) in a random-effects meta-analysis. Results: A total of 35 studies were included and included 20,520 students. The mean age was 22.1 ± 5.1 years with a predominance of female sex (sex ratio F/M = 1.05). The vaccination coverage rate was 28.8% [95% CI: 22.9% - 34.7%]. Disaggregation allowed to estimate coverage rates of 29.8% [95% CI: 22.9% - 36.7%], 23.4% [95% CI: 9.4% - 37.4%] and 17.0% [95% CI: 14.4% - 19.5%] respectively in West Africa, East Africa and Central Africa. Conclusion: Less than a third of students in sub-Saharan Africa are protected against hepatitis B. However, the majority of this target group is at risk of infection. It would be relevant to screen and, if necessary, vaccinate all new students. 展开更多
关键词 Hepatitis B Vaccination coverage STUDENTS Sub-Saharan Africa
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Detecting the distribution of and public attitudes to charismatic alien species based on media coverage
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作者 Yuexuan Liu Ruichang Sun +1 位作者 Bo Li Zhijun Ma 《Avian Research》 SCIE CSCD 2024年第3期379-384,共6页
Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a chari... Charismatic species are often reported by the media,providing information for detecting population status and public perception.To identify the number and distribution of free-living Black Swan(Cygnus atratus),a charismatic alien species in Chinese mainland and to detect the public and the media attitudes to the species,we analyzed the reports and emotional tendency from media coverage in 2000-2022 using manual reading,crawler extraction and latent Dirichlet allocation.A total of 6654 Black Swans were reported at 711 sites,including 147 individuals at 30 nature reserves.Successful breeding was reported at one-fourth of the total sites,including five nature reserves.The proportion of positive emotional tendency to Black Swans was overwhelming in the reports and was higher than that to alien species in general,suggesting that the public and the media are unaware of the risk of biological invasion.Effective management of invasive species requires the media clarifies the invasion risk of charismatic alien species.Promoting the unity between the harmfulness of abstract concept of alien species and the charisma of a specific alien species among the public help effective management. 展开更多
关键词 Alien species Biological invasion Cygnus atratus Emotional tendency Invasive species Media coverage Public perception
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Scheduling optimization for UAV communication coverage using virtual force-based PSO model
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作者 Jianguo Sun Wenshan Wang +2 位作者 Sizhao Li Qingan Da Lei Chen 《Digital Communications and Networks》 SCIE CSCD 2024年第4期1103-1112,共10页
When the ground communication base stations in the target area are severely destroyed,the deployment of Unmanned Aerial Vehicle(UAV)ad hoc networks can provide people with temporary communication services.Therefore,it... When the ground communication base stations in the target area are severely destroyed,the deployment of Unmanned Aerial Vehicle(UAV)ad hoc networks can provide people with temporary communication services.Therefore,it is necessary to design a multi-UAVs cooperative control strategy to achieve better communication coverage and lower energy consumption.In this paper,we propose a multi-UAVs coverage model based on Adaptive Virtual Force-directed Particle Swarm Optimization(AVF-PSO)strategy.In particular,we first introduce the gravity model into the traditional Particle Swarm Optimization(PSO)algorithm so as to increase the probability of full coverage.Then,the energy consumption is included in the calculation of the fitness function so that maximum coverage and energy consumption can be balanced.Finally,in order to reduce the communication interference between UAVs,we design an adaptive lift control strategy based on the repulsion model to reduce the repeated coverage of multi-UAVs.Experimental results show that the proposed coverage strategy based on gravity model outperforms the existing state-of-the-art approaches.For example,in the target area of any size,the coverage rate and the repeated coverage rate of the proposed multi-UAVs scheduling are improved by 6.9–29.1%,and 2.0–56.1%,respectively.Moreover,the proposed scheduling algorithm is high adaptable to diverse execution environments.©2022 Published by Elsevier Ltd. 展开更多
关键词 Multi-UAVs Ad hoc network Area collaborative coverage Gravity model Swarm optimization algorithm Random topology
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Distributed collaborative complete coverage path planning based on hybrid strategy
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作者 ZHANG Jia DU Xin +1 位作者 DONG Qichen XIN Bin 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第2期463-472,共10页
Collaborative coverage path planning(CCPP) refers to obtaining the shortest paths passing over all places except obstacles in a certain area or space. A multi-unmanned aerial vehicle(UAV) collaborative CCPP algorithm ... Collaborative coverage path planning(CCPP) refers to obtaining the shortest paths passing over all places except obstacles in a certain area or space. A multi-unmanned aerial vehicle(UAV) collaborative CCPP algorithm is proposed for the urban rescue search or military search in outdoor environment.Due to flexible control of small UAVs, it can be considered that all UAVs fly at the same altitude, that is, they perform search tasks on a two-dimensional plane. Based on the agents’ motion characteristics and environmental information, a mathematical model of CCPP problem is established. The minimum time for UAVs to complete the CCPP is the objective function, and complete coverage constraint, no-fly constraint, collision avoidance constraint, and communication constraint are considered. Four motion strategies and two communication strategies are designed. Then a distributed CCPP algorithm is designed based on hybrid strategies. Simulation results compared with patternbased genetic algorithm(PBGA) and random search method show that the proposed method has stronger real-time performance and better scalability and can complete the complete CCPP task more efficiently and stably. 展开更多
关键词 multi-agent cooperation unmanned aerial vehicles(UAV) distributed algorithm complete coverage path planning(CCPP)
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Spatio-temporal response of vegetation coverage at multiple time scales to extreme climate in the Qinling mountains in Northwest China
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作者 Qing Meng XiaoBang Peng ShanHong Zhang 《Research in Cold and Arid Regions》 CSCD 2024年第6期302-309,共8页
Monitoring spatio-temporal variations in vegetation coverage and linking them to climatic drivers is crucial for guiding environmental management and understanding climate change.In this study,Pearson's correlatio... Monitoring spatio-temporal variations in vegetation coverage and linking them to climatic drivers is crucial for guiding environmental management and understanding climate change.In this study,Pearson's correlation,MODIS NDVI time series,precipitation and temperature data,and extreme climate indices were used to investigate the response of vegetation to extreme climate at the monthly,seasonal,and yearly scales in the Qinling Mountains(QMs)in China from 2001 to 2020.The results indicate that vegetation coverage increased over time at a rate of 2.9×10^(-3) per year.The QMs exhibited good vegetation coverage(average NDVI?0.64),with over 64% of the area featuring NDVI values between 0.60 and 0.80.The Mean center was located in Ningshan County on the southern slope of the QMs.The spatial pattern of the annual average NDVI on the northern and southern slopes of the QMs was consistent with the seasonal average variation,with high values in the middle and low values at the edges.As transitional climate regions,the QMs exert a significant impact on vegetation.Spring maximum continuous 5-day monthly precipitation(Rx5day)and spring precipitation were the two most significant positive controlling factors affecting vegetation.Specifically,aside from water bodies,grasslands exhibited the largest response to these two factors.Good vegetation conditions in the QMs are of great significance for regulating climate and conserving water sources.Furthermore,they are important for controlling the response of vegetation to climatic conditions and,in a deeper sense,are of great significance for vegetation restoration,ecological protection,and carbon neutrality. 展开更多
关键词 Vegetation coverage Extreme climate The Qinling mountains Multiple scales
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Enhancing ^(*)CO coverage on Sm-Cu_(2)O via 4f-3d orbital hybridization for highly efficient electrochemical CO_(2) reduction to C_(2)H_(4)
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作者 Xiaojun Wang Lanlan Shi +11 位作者 Weikun Ren Jingxian Li Yuanming Liu Weijie Fu Shiyu Wang Shuyun Yao Yingjie Ji Kang Ji Liwen Zhang Zhiyu Yang Jiangzhou Xie Yi-Ming Yan 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第12期409-416,共8页
The electrocatalytic conversion of CO_(2) into valuable chemical feedstocks using renewable electricity offers a compelling strategy for closing the carbon loop.While copper-based materials are effective in catalyzing... The electrocatalytic conversion of CO_(2) into valuable chemical feedstocks using renewable electricity offers a compelling strategy for closing the carbon loop.While copper-based materials are effective in catalyzing CO_(2) to C_(2+)products,the instability of Cu^(+)species,which tend to reduce to Cu~0 at cathodic potentials during CO_(2) reduction,poses a significant challenge.Here,we report the development of SmCu_(2)O and investigate the influence of f-d orbital hybridization on the CO_(2) reduction reaction (CO_(2)RR).Supported by density functional theory (DFT) calculations,our experimental results demonstrate that hybridization between Sm^(3+)4f and Cu^(+)3d orbitals not only improves the adsorption of *CO intermediates and increases CO coverage to stabilize Cu^(+) but also facilitates CO_(2) activation and lowers the energy barriers for CAC coupling.Notably,Sm-Cu_(2)O achieves a Faradaic efficiency for C_(2)H_(4) that is 38%higher than that of undoped Cu_(2)O.Additionally,it sustains its catalytic activity over an extended operational period exceeding 7 h,compared to merely 2 h for the undoped sample.This research highlights the potential of fd orbital hybridization in enhancing the efficacy of copper-based catalysts for CO_(2)RR,pointing towards a promising direction for the development of durable,high-performance electrocatalysts for sustainable chemical synthesis. 展开更多
关键词 Electrochemical CO_(2)reduction F-d orbital hybridization Adsorption of^(*)CO CO coverage C_(2+)products
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Modern Corrosion Mapping of Storage Tank Bottoms--Notable Advancements in Critical Zone Coverage,Inspection Efficiency and Data Integrity
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作者 Andrew J.Simpson Matthew A.Boat 《Journal of Civil Engineering and Architecture》 2024年第3期148-153,共6页
Every day,an NDT(Non-Destructive Testing)report will govern key decisions and inform inspection strategies that could affect the flow of millions of dollars which ultimately affects local environments and potential ri... Every day,an NDT(Non-Destructive Testing)report will govern key decisions and inform inspection strategies that could affect the flow of millions of dollars which ultimately affects local environments and potential risk to life.There is a direct correlation between report quality and equipment capability.The more able the equipment is-in terms of efficient data gathering,signal to noise ratio,positioning,and coverage-the more actionable the report is.This results in optimal maintenance and repair strategies providing the report is clear and well presented.Furthermore,when considering tank floor storage inspection it is essential that asset owners have total confidence in inspection findings and the ensuing reports.Tank floor inspection equipment must not only be efficient and highly capable,but data sets should be traceable and integrity maintained throughout.Corrosion mapping of large surface areas such as storage tank bottoms is an inherently arduous and time-consuming process.MFL(magnetic flux leakage)based tank bottom scanners present a well-established and highly rated method for inspection.There are many benefits of using modern MFL technology to generate actionable reports.Chief among these includes efficiency of coverage while gaining valuable information regarding defect location,severity,surface origin and the extent of coverage.More recent advancements in modern MFL tank bottom scanners afford the ability to scan and record data sets at areas of the tank bottom which were previously classed as dead zones or areas not scanned due to physical restraints.An example of this includes scanning the CZ(critical zone)which is the area close to the annular to shell junction weld.Inclusion of these additional dead zones increases overall inspection coverage,quality and traceability.Inspection of the CZ areas allows engineers to quickly determine the integrity of arguably the most important area of the tank bottom.Herein we discuss notable developments in CZ coverage,inspection efficiency and data integrity that combines to deliver an actionable report.The asset owner can interrogate this report to develop pertinent and accurate maintenance and repair strategies. 展开更多
关键词 Storage tank tank bottom CZ MFL stars CORROSION corrosion-mapping EFFICIENCY coverage paperless reporting data traceability
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Cluster sampling methodology to evaluate immunization coverage
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作者 Aishwarya Sharma RB Jain +3 位作者 Jitesh Satija Aditi Sharma Avani Sharma Sudhir Shekhawat 《World Journal of Methodology》 2024年第3期78-89,共12页
BACKGROUND Immunization is a key component of primary health care and an indisputable human right.Vaccines are critical to the prevention and control of infectious disease outbreaks.The coronavirus disease 2019(COVID-... BACKGROUND Immunization is a key component of primary health care and an indisputable human right.Vaccines are critical to the prevention and control of infectious disease outbreaks.The coronavirus disease 2019(COVID-19)pandemic and associated disruptions over the past two years have strained the health systems,with many children missing out on essential childhood vaccines.AIM To evaluate the immunization coverage among 12-23-month-old children in the rural areas of Community Health Centre(CHC)Dighal and to determine the factors influencing the existing immunization coverage.METHODS A coverage evaluation survey was conducted according to the 30-cluster sampling technique,which is the standard methodology for such surveys devised by World Health Organization.A total of 300 children aged 12-23 months were included,whose immunization details were noted from their immunization cards.RESULTS Full immunization rate was noted in 86.7%of the children,with partial and non-immunized children accounting for 9%and 4.3%respectively.The full immunization dropout rate was 4.2%.The common reasons for partial or non-immunization were family problem including illness of mother,vaccine not being available and child being ill.Place of birth(P=0.014)and availability of immunization card(P<0.001)were significant predictors of the immunization status.Since the study was conducted in 2020/2021,health services were disrupted due to the COVID-19 lockdown.CONCLUSION Due to the coverage being higher than the national average,it was concluded that the immunization coverage was optimal and not affected by the COVID-19 pandemic. 展开更多
关键词 Immunization coverage CHILDREN COVID 19 pandemic Vaccines Family health Routine immunization
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Analysis of Mobile and Internet Network Coverage: Propagation of Electromagnetic Waves and Concept of Digital Divide in Burundi
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作者 Apollinaire Bigirimana Jérémie Ndikumagenge +2 位作者 Sami Tabbane Romeo Nibitanga Hassan Kibeya 《Open Journal of Antennas and Propagation》 2024年第1期1-18,共18页
Mobile and Internet network coverage plays an important role in digital transformation and the exploitation of new services. The evolution of mobile networks from the first generation (1G) to the 5th generation is sti... Mobile and Internet network coverage plays an important role in digital transformation and the exploitation of new services. The evolution of mobile networks from the first generation (1G) to the 5th generation is still a long process. 2G networks have developed the messaging service, which complements the already operational voice service. 2G technology has rapidly progressed to the third generation (3G), incorporating multimedia data transmission techniques. It then progressed to fourth generation (4G) and LTE (Long Term Evolution), increasing the transmission speed to improve 3G. Currently, developed countries have already moved to 5G. In developing countries, including Burundi, a member of the East African Community (ECA) where more than 80% are connected to 2G technologies, 40% are connected to the 3G network and 25% to the 4G network and are not yet connected to the 5G network and then still a process. The objective of this article is to analyze the coverage of 2G, 3G and 4G networks in Burundi. This analysis will make it possible to identify possible deficits in order to reduce the digital divide between connected urban areas and remote rural areas. Furthermore, this analysis will draw the attention of decision-makers to the need to deploy networks and coverage to allow the population to access mobile and Internet services and thus enable the digitalization of the population. Finally, this article shows the level of coverage, the digital divide and an overview of the deployment of base stations (BTS) throughout the country to promote the transformation and digital inclusion of services. 展开更多
关键词 coverage of Mobile Networks and Internet Digital Divide Rural and Isolated Areas Antenna Connectivity and Digital Inclusion
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Building a resilient health system for universal health coverage and health security:a systematic review
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作者 Ayal Debie Adane Nigusie +2 位作者 Dereje Gedle Resham B.Khatri Yibeltal Assefa 《Global Health Research and Policy》 2024年第1期596-612,共17页
Background Resilient health system(RHS)is crucial to achieving universal health coverage(UHC)and health secu-rity.However,little is known about strategies towards RHS to improve UHC and health security.This systematic... Background Resilient health system(RHS)is crucial to achieving universal health coverage(UHC)and health secu-rity.However,little is known about strategies towards RHS to improve UHC and health security.This systematic review aims to synthesise the literature to understand approaches to build RHS toward UHC and health security.Methods A systematic search was conducted including studies published from 01 January 2000 to 31 Decem-ber 2021.Studies were searched in three databases(PubMed,Embase,and Scopus)using search terms under four domains:resilience,health system,universal health coverage,and health security.We critically appraised articles using Rees and colleagues’quality appraisal checklist to assess the quality of papers.A systematic narrative synthesis was conducted to analyse and synthesise the data using the World Health Organization’s health systems building block framework.Results A total of 57 articles were included in the final review.Context-based redistribution of health workers,task-shifting policy,and results-based health financing policy helped to build RHS.High political commitment,commu-nity-based response planning,and multi-sectorial collaboration were critical to realising UHC and health security.On the contrary,lack of access,non-responsive,inequitable healthcare services,poor surveillance,weak leadership,and income inequalities were the constraints to achieving UHC and health security.In addition,the lack of basic healthcare infrastructures,inadequately skilled health workforces,absence of clear government policy,lack of clarity of stakeholder roles,and uneven distribution of health facilities and health workers were the challenges to achieving UHC and health security.Conclusions Advanced healthcare infrastructures and adequate number of healthcare workers are essential to achieving UHC and health security.However,they are not alone adequate to protect the health system from poten-tial failure.Context-specific redistribution of health workers,task-shifting,result-based health financing policies,and integrated and multi-sectoral approaches,based on the principles of primary health care,are necessary for build-ing RHS toward UHC and health security. 展开更多
关键词 Health system Health security Resilient Universal health coverage
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Universal coverage for oral health care in 27 low-income countries:a scoping review
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作者 Yiqun Luan Divesh Sardana +9 位作者 Ashiana Jivraj David Liu Nishmi Abeyweera Yajin Zhao Jacqueline Cellini Michelle Bass Jing Wang Xinran Lu Zheyi Cao Chunling Lu 《Global Health Research and Policy》 2024年第1期231-250,共20页
Background Low-income countries bear a growing and disproportionate burden of oral diseases.With the World Health Organization targeting universal oral health coverage by 2030,assessing the state of oral health covera... Background Low-income countries bear a growing and disproportionate burden of oral diseases.With the World Health Organization targeting universal oral health coverage by 2030,assessing the state of oral health coverage in these resource-limited nations becomes crucial.This research seeks to examine the political and resource commit-ments to oral health,along with the utilization rate of oral health services,across 27 low-income countries.Methods We investigated five aspects of oral health coverage in low-income countries,including the integration of oral health in national health policies,covered oral health services,utilization rates,expenditures,and the number of oral health professionals.A comprehensive search was conducted across seven bibliographic databases,three grey literature databases,and national governments’and international organizations’websites up to May 2023,with no lin-guistic restrictions.Countries were categorized into“full integration”,“partial integration”,or“no integration”based on the presence of dedicated oral health policies and the frequency of oral health mentions.Covered oral health ser-vices,utilization rates,expenditure trends,and the density of oral health professionals were analyzed using evidence from reviews and data from World Health Organization databases.Results A total of 4242 peer-reviewed and 3345 grey literature texts were screened,yielding 12 and 84 files respec-tively to be included in the final review.Nine countries belong to“full integration”and thirteen countries belong to“partial integration”,while five countries belong to“no integration”.Twelve countries collectively covered 26 types of oral health care services,with tooth extraction being the most prevalent service.Preventive and public health-based oral health interventions were scarce.Utilization rates remained low,with the primary motivation for seeking care being dental pain relief.Expenditures on oral health were minimal,predominantly relying on domestic private sources.On average,the 27 low-income countries had 0.51 dentists per 10,000 population,contrasting with 2.83 and 7.62 in middle-income and high-income countries.Conclusions Oral health care received little political and resource commitment toward achieving universal health coverage in low-income countries.Urgent action is needed to mobilize financial and human resources,and integrate preventive and public health-based interventions. 展开更多
关键词 Oral health Universal health coverage Low-income countries
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Leaving no one behind in armed conflict-affected settings of Africa:is universal health coverage a possibility or mirage?
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作者 Olushayo Oluseun Olu Amos Petu Abdulmumini Usman 《Global Health Research and Policy》 2024年第1期423-431,共9页
The world is off track six years to the 2030 deadline for attaining the sustainable development goals and universal health coverage.This is particularly evident in Africa’s armed conflict-affected and humanitarian se... The world is off track six years to the 2030 deadline for attaining the sustainable development goals and universal health coverage.This is particularly evident in Africa’s armed conflict-affected and humanitarian settings,where perva-sively weak health systems,extreme poverty and inequitable access to the social dimensions and other determinants of health continue to pose significant challenges to universal health coverage.In this article,we review the key issues and main barriers to universal health coverage in such settings.While our review shows that the current health service delivery and financing models in Africa’s armed conflict-affected settings provide some opportunities to leapfrog progress,others are threats which could hinder the attainment of universal health coverage.We propose four key approaches focused on addressing the barriers to the three pillars of universal health coverage,strengthening public disaster risk management,bridging the humanitarian-development divide,and using health as an enabler of peace and sustainable development as panacea to addressing the universal health coverage challenge in these settings.The principles of health system strengthening,primary health care,equity,the right to health,and gender mainstreaming should underscore the implementation of these approaches.Moving forward,we call for more advocacy,dialogue,and research to better define and adapt these approaches into a realistic package of interventions for attaining uni-versal health coverage in Africa’s armed conflict-affected settings. 展开更多
关键词 Universal health coverage Sustainable development goals Conflicted-affected settings Humanitarian-development divide AFRICA
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MASC:一种基于移动辅助节点的Sweep Coverage机制 被引量:6
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作者 林锋 王伟 周激流 《四川大学学报(工程科学版)》 EI CAS CSCD 北大核心 2010年第6期119-125,132,共8页
为了改进Sweep Coverage机制的性能,引入了移动辅助节点来辅助数据传输,并在此基础上提出了一种两层结构的Sweep Coverage机制(Mobile-Assisted Sweep Coverage,MASC)。MASC首先将POI分配给移动传感器节点完成数据采集,然后通过移动辅... 为了改进Sweep Coverage机制的性能,引入了移动辅助节点来辅助数据传输,并在此基础上提出了一种两层结构的Sweep Coverage机制(Mobile-Assisted Sweep Coverage,MASC)。MASC首先将POI分配给移动传感器节点完成数据采集,然后通过移动辅助节点来实现移动传感器节点和汇聚节点间数据的中继。仿真结果表明,在相同的网络场景下,提出的MASC机制较以往的覆盖机制取得更好的性能表现。 展开更多
关键词 无线传感器网络 覆盖机制 SWEEP coverage 移动辅助节点 移动控制
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