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Examining the Level of Service in the Context of Recreational Carrying Capacity in the Erzurum Urban Forest,Turkey
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作者 Tendu Hilal Goktug Nalan Demircioglu Yildiz +1 位作者 Metin Demir Burcu Mestav 《Journal of Environmental Protection》 2015年第9期1014-1028,共15页
Urban forests are confronted with high using pressure because of the increasing demand for recreation and accessibility of these settings. For that purpose, defining and managing recreational carrying capacity is cons... Urban forests are confronted with high using pressure because of the increasing demand for recreation and accessibility of these settings. For that purpose, defining and managing recreational carrying capacity is considered as significant in ensuring ecological value’s and recreational satisfaction’s continuity. The purpose of this paper is to investigate the carrying capacity of Erzurum Urban Forest with respect to Level of Service (LOS) as a new management technique that focuses on service quality and visitor satisfaction. The data were obtained by self-administered questionnaire conducted with 166 visitors on weekends and holidays during summer season of the year 2014. Data were analyzed by dimensions/indicators of recreational satisfaction and socio-demographic characteristics with intent to identify tolerance range of visitors. The contribution and relative importance of each of the indicators to the overall satisfaction were analyzed by using Ordinal Logistic Model (OLM). The results indicated that the four indicators were at the greatest degree;“distance from picnic spot to toilets” and “quantity of children’s playground facilities” were decease of overall satisfaction while “distance from picnic spot to parking” and “level of shade at picnic spot” had a positive contribution to the overall satisfaction. The outputs from these analyses were used to calculate LOS. It was revealed that the level of service (0.40) in Erzurum Urban Forest was below the moderate level. Planning and managing strategies for optimizing the LOS were developed and discussed by considering these results. 展开更多
关键词 Recreational Carrying capacity level of service Visitor Satisfaction Recreation Planning and Management Erzurum Urban Forest
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Pedestrian Facilities Capacity and Level of Service at Intersections in a Connected and Autonomous Vehicle Environment 被引量:2
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作者 Yifan Wang Ardeshir Faghri +2 位作者 Dian Yuan Michael L. Vaughan Mingxin Li 《Journal of Transportation Technologies》 2019年第4期423-438,共16页
It is inevitable that Connected and Autonomous Vehicles (CAVs) will be a major focus of transportation and the automotive industry with increased use in future traffic system analysis. Numerous studies have focused on... It is inevitable that Connected and Autonomous Vehicles (CAVs) will be a major focus of transportation and the automotive industry with increased use in future traffic system analysis. Numerous studies have focused on the evaluation and potential development of CAVs technology;however, pedestrians and bicyclists, as two essential and important modes of the road users have seen little to no coverage. In response to the need for analyzing the impact of CAVs on non-motorized transportation, this paper develops a new model for the evaluation of the Level of Service (LOS) for pedestrians in a CAVs environment based on the Highway Capacity Manual (HCM). The HCM provides a methodology to assess the level of service for pedestrians and bicyclists on various types of intersections in urban areas. Five scenarios were created for simulation via VISSIM (a software) that corresponds to the different proportions of the CAVs and different signal systems in a typical traffic environment. Alternatively, the Surrogate Safety Assessment Model (SSAM) was selected for analyzing the safety performance of the five scenarios. Through computing and analyzing the results of simulation and SSAM, the latter portion of this paper focuses on the development of a new model for evaluating pedestrian LOS in urban areas which are based upon HCM standards which are suitable for CAVs environments. The results of this study are intended to inform the future efforts of engineers and/or policymakers and to provide them with a tool to conduct a comparison of capacity and LOS related to the impact of CAVs on pedestrians during the process of a transportation system transition to CAVs. 展开更多
关键词 CONNECTED and AUTONOMOUS VEHICLES PEDESTRIANS VISSIM level of service SSAM
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A study on service capacity of primary medical and health institutions for cervical cancer screening in urban and rural areas in China 被引量:6
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作者 Yang Li Li Ma +5 位作者 Chunxia Yang Zhangya Chen Yuqian Zhao Le Dang Jinghe Lang Youlin Qiao 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2019年第5期838-848,共11页
Objective: To provide a decision-making basis for sustainable and effective development of cervical cancer screening.Methods: This cross-sectional study assesses the service capacity to conduct cervical cancer screeni... Objective: To provide a decision-making basis for sustainable and effective development of cervical cancer screening.Methods: This cross-sectional study assesses the service capacity to conduct cervical cancer screening with a sample of 310 medical staff, medical institutions and affiliated township health centers from 20 countylevel/district-level areas in 14 Chinese provinces in 2016.Results: The county-level/district-level institutions were the main prescreening institutions for cervical cancer screening. More medical staff have become engaged in screening, with a significantly higher amounts in urban than in rural areas(P<0.05). The number of human papillomavirus(HPV) testers grew the fastest(by 225% in urban and 125% in rural areas) over the course of the project. HPV testing took less time than cytology to complete the same number of screening tasks in both urban and rural areas. The proportion of mid-level professionals was the highest among the medical staff, 40.0% in urban and 44.7% in rural areas(P=0.406), and most medical staff had a Bachelor’s degree, accounting for 76.3% in urban and 52.0% in rural areas(P<0.001). In urban areas, 75.0% were qualified medical staff, compared with 68.0% in rural areas, among which the lowest proportion was observed for rural cytology inspectors(22.7%). The medical equipment for cervical pathology diagnosis in urban areas was better(P<0.001). HPV testing equipment was relatively adequate(typing test equipment was 70% in urban areas, and non-typing testing equipment was 70% in rural areas).Conclusions: The service capacity of cervical cancer screening is insufficient for the health needs of the Chinese population. HPV testing might be an optimal choice to fill the needs of cervical cancer screening given current Chinese medical health service capacity. 展开更多
关键词 China CERVICAL cancer SCREENING health service capacity APPROPRIATE technology CYTOLOGY TESTING HPV TESTING
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Boundary determination of leveling capacity for plate roller leveler based on curvature integration method 被引量:2
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作者 刘志芳 罗远新 +1 位作者 严兴春 王勇勤 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4608-4615,共8页
Leveler is widely used to improve the quality of defective mild steel plates.Its typical ranges of the leveling capacity are constrained by three criteria,namely the maximum stroke of rollers,allowable total leveling ... Leveler is widely used to improve the quality of defective mild steel plates.Its typical ranges of the leveling capacity are constrained by three criteria,namely the maximum stroke of rollers,allowable total leveling force and motor power.In this work,an optimization model with equality and inequality constraints was built for the maximum yield stress search of each thickness of plates.The corresponding search procedure with three loops was given.The approximate range by the simplification model could be used as the initial value for the actual range search of the leveling capacity.Therefore,the search speed could be accelerated compared with a global search.The consistency of the analytical results and field data demonstrates the reliability of the proposed model and procedure.The typical ranges of the leveling capacity are expressed by several boundary curves which are helpful to judge whether the incoming plate can be leveled quickly or not.Also,these curves can be used to find the maximum yield stress for a specific thickness or the maximum thickness for a yield stress for plates. 展开更多
关键词 plastic ratio leveling capacity curvature integration PLATE
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Effects of Plastic Film Mulching on Soil Carbon Fixation Capacity and Fertility Level in Eastern Qinghai
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作者 Kai YANG Qinglan HU Jingui WANG 《Asian Agricultural Research》 2022年第1期60-65,共6页
[Objectives]To explore the effects of single application of chemical fertilizers on soil carbon fixation capacity and soil fertility under plastic film mulching conditions in eastern Qinghai,and to provide a theoretic... [Objectives]To explore the effects of single application of chemical fertilizers on soil carbon fixation capacity and soil fertility under plastic film mulching conditions in eastern Qinghai,and to provide a theoretical basis for realizing the sustainable development of film mulching planting method in this area.[Methods]The effects of single application of chemical fertilizer cultivation mode under film mulching conditions on the soil organic carbon(SOC),labile organic carbon(LOC),carbon management index(CMI),extractable humus carbon(CHE),humic acid carbon(CHA),and fulvic acid carbon(CFA)in the cultivated layer(0-20 cm)were studied through three consecutive years of field experiments on dryland maize farmland in the eastern Qinghai.[Results]Under the film mulching condition,the SOC,LOC and CMI of the single application of chemical fertilizer cultivation mode were lower than that of the open field control.CHE,CHA and CFA increased with the increase of planting years,but the degree of increase was generally less than that of the open field control.With the increase of planting years,by 2020,the soil LOC/SOC value of film mulching decreased by 4.97%compared with before the start of the experiment,while the open field control increased by 1.11%;the organic carbon oxidation stability coefficient(KOS)of the film mulching was higher than that of the open field control;the soil CHA/CFA value and PQ value were higher than that of the open field control.[Conclusions]Under the condition of single application of chemical fertilizers,the continuous film mulching cultivation mode reduces the soil carbon fixation capacity,and soil organic carbon tends to be stable,which is not conducive to biological utilization and could reduce the soil fertility and degrade the soil quality,causing adverse effects on the stability of crop yield and sustainable production in the long run. 展开更多
关键词 SOIL Carbon fixation capacity Fertility level Organic carbon HUMUS Plastic film mulching
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The Sensitivity of Model Results to Specification of Network-Based Level of Service Attributes: An Application of a Mixed Logit Model to Trave Mode Choice
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作者 Bharat P. Bhatta 《Journal of Transportation Technologies》 2011年第3期34-46,共13页
The need for travel demand models is growing worldwide. Obtaining reasonably accurate level of service (LOS) attributes of different travel modes such as travel time and cost representing the performance of transporta... The need for travel demand models is growing worldwide. Obtaining reasonably accurate level of service (LOS) attributes of different travel modes such as travel time and cost representing the performance of transportation system is not a trivial task, especially in growing cities of developing countries. This study investigates the sensitivity of results of a travel mode choice model to different specifications of network-based LOS attributes using a mixed logit model. The study also looks at the possibilities of correcting some of the inaccuracies in network-based LOS attributes. Further, the study also explores the effects of different specifications of LOS data on implied values of time and aggregation forecasting. The findings indicate that the implied values of time are very sensitive to specification of data and model implying that utmost care must be taken if the purpose of the model is to estimate values of time. Models estimated on all specifications of LOS-data perform well in prediction, likely suggesting that the extra expense on developing a more detailed and accurate network models so as to derive more precise LOS attributes is unnecessary for impact analyses of some policies. 展开更多
关键词 Data SPECIFICATION level of service Attributes TRAVEL Mode CHOICE Network Models Mixed LOGIT ERROR Components LOGIT
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Bicycle Level of Service Evaluation Method for Urban Road Segment
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作者 Shinan Shu Yang Bian +1 位作者 Jian Rong Shuang Li 《Open Journal of Applied Sciences》 2018年第2期80-88,共9页
As a sustainable mode of transportation, bicycles significantly improve daily mobility. In order to provide theoretics support for improvement of the bicycling environment, this paper proposed bicycle level of service... As a sustainable mode of transportation, bicycles significantly improve daily mobility. In order to provide theoretics support for improvement of the bicycling environment, this paper proposed bicycle level of service (BLOS) evaluation method for urban road segment according to cyclists’ perception. First, influence factors of BLOS were identified from aspects of road facility, traffic characteristics, and environmental condition. Second, bicycling videos were recorded and a satisfaction survey was conducted. Four BLOS evaluation models for different separation facilities were established. Last, bicycling behavioral stages of travelers were divided based on the transtheoretical model. A new BLOS classification criterion was proposed according to travelers’ demand of different stages. 展开更多
关键词 BICYCLE level of service Classification CRITERIA BEHAVIORAL STAGE The Transtheoretical Model
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Measurement and assessment of water resources carrying capacity in Henan Province, China 被引量:9
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作者 Ming Dou Jun-xia Ma +1 位作者 Gui-qiu Li Qi-ting Zuo 《Water Science and Engineering》 EI CAS CSCD 2015年第2期102-113,共12页
As demands on limited water resources intensify, concerns are being raised about water resources carrying capacity(WRCC), which is defined as the maximum sustainable socioeconomic scale that can be supported by avai... As demands on limited water resources intensify, concerns are being raised about water resources carrying capacity(WRCC), which is defined as the maximum sustainable socioeconomic scale that can be supported by available water resources and while maintaining defined environmental conditions. This paper proposes a distributed quantitative model for WRCC, based on the principles of optimization, and considering hydro-economic interaction, water supply, water quality, and socioeconomic development constraints. With the model, the WRCCs of 60 subregions in Henan Province were determined for different development periods. The results showed that the water resources carrying level of Henan Province was suitably loaded in 2010, but that the province would be mildly overloaded in 2030 with respect to the socioeconomic development planning goals. The restricting factors for WRCC included the available water resources, the increasing rate of GDP, the urbanization ratio, the irrigation water utilization coefficient, the industrial water recycling rate, and the wastewater reuse rate, of which the available water resources was the most crucial factor. Because these factors varied temporally and spatially, the trends in predicted WRCC were inconsistent across different subregions and periods. 展开更多
关键词 Water resources carrying capacity Hydro-economic interaction Sustainable socioeconomic scale Water resources carrying level Henan Province
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Evaluation of regional water resources carrying capacity based on binary index method and reduction index method 被引量:13
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作者 Hong-yuan Fang Sheng-wei Gan Chen-ying Xue 《Water Science and Engineering》 EI CAS CSCD 2019年第4期263-273,共11页
Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereaf... Based on the regional water resources carrying capacity(WRCC)evaluation principles and evaluation index system in the National Technical Outline of Water Resources Carrying Capacity Monitoring and Early Warning(hereafter referred to as the Technical Outline),this paper elaborates on the collection and sorting of the basic data of water resources conditions,water resources development and utilization status,social and economic development in basins,analysis and examination of integrity,consistency,normativeness,and rationality of the basic data,and the necessity of WRCC evaluation.This paper also describes the technique of evaluating the WRCC in prefecture-level cities and city-level administrative divisions in the District of the Taihu Lake Basin,which is composed of the Taihu Lake Basin and the Southeastern River Basin.The evaluation process combines the binary index evaluation method and reduction index evaluation method.The former,recommended by the Technical Outline,uses the total water use and the amount of exploited groundwater as evaluation indices,showing stronger operability,while the latter is developed by simplifying and optimizing the comprehensive index system with greater systematicness and completeness.The mutual validation and adjustment of the results of the above-mentioned two evaluation methods indicate that the WRCC of the District of the Taihu Lake Basin is overloaded in general because some prefecture-level cities and city-level administrative divisions in the Taihu Lake Basin and the Southeastern River Basin are in a severely overloaded state.In order to explain this conclusion,this paper analyzes the causes of WRCC overloading from the aspects of basin water environment,water resources development and utilization,water resources regulation and control ability,water resources utilization efficiency,and water resources management. 展开更多
关键词 Water resources carrying capacity(WRCC) EVALUATION Binary index method Reduction index method Prefecture-level cities and city-level administrative divisions
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Combined Bearing Capacity of Spudcans on a Double Layer Deposit of Strong-Over-Weak Clays
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作者 YIN Qilin DONG Sheng 《Journal of Ocean University of China》 SCIE CAS CSCD 2019年第1期133-143,共11页
An extreme sea storm process can lead to a jack-up rig under the combined loading condition of vertical load(V), horizontal load(H), and moment(M) to have stability problems. This paper presents the analysis of combin... An extreme sea storm process can lead to a jack-up rig under the combined loading condition of vertical load(V), horizontal load(H), and moment(M) to have stability problems. This paper presents the analysis of combined bearing capacities of a circular spudcan on layered clays with a strong layer overlying a comparatively weaker layer. Numerical models combined with displacement-based load tests, swipe tests, and constant ratio displacement probe tests are adopted to calculate the uniaxial bearing capacities, failure envelopes in combined V-H, V-M planes, and failure envelopes in a combined V-H-M load space, respectively. A parametric study on the effects of vertical load level V, the layer strength ratio s_(u,t)/s_(u,b), and the hard layer thickness t_1 on the bearing capacities is then performed. Results show that the vertical load level is a key factor that influences the values of H and M and the size of the H-M failure envelope. The existence of the underlying weak clay decreases the bearing capacities in all directions, and the vertical capacity Vult is affected more than the horizontal(H_(ult)) and moment(M_(ult)) capacities based on a single uniform deposit. The influence of the underlying weak clay on H-M failure envelope is mainly shown where H and M are coupled in the same direction. In contrast, little difference is observed when H and M are coupled in opposite directions. 展开更多
关键词 COMBINED bearing capacity circular SPUDCAN LAYERED clays vertical load level strength ratio hard layer thickness
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Sector Capacity Estimation Based on Differentiated Routes and Busy Levels
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作者 Dong Xiangning Hu minghua Washington Yotto Ochieng 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2017年第4期438-448,共11页
Sector capacity estimation plays an important role in applied research of airspace management.Previous researches manifest that sector capacity should be influenced by its standard flow,or routes in that sector.Howeve... Sector capacity estimation plays an important role in applied research of airspace management.Previous researches manifest that sector capacity should be influenced by its standard flow,or routes in that sector.However,if air traffic controller(ATCO)workload busy levels(level of proactivity of an ATCO)are ignored,the estimated sector capacity may not be accurate.There is a need to compare the estimated sector capacity with and without busy levels consideration,both with differentiated routes consideration.This paper proposes a method for sector capacity estimation based on ATCO workload considering differentiated routes and busy levels.Firstly,the main routes in the sector are identified,and for each route,the ATCO workload per flight is determined.Secondly,the workload for each route at three busy levels is determined.Regression analysis is then applied to determine the relationship between workload and the number of flights(with and without considering busy levels)in 15 min and 1h time slices.Sector capacity is then determined on the basis of a specified workload threshold,for the two cases with and without considering busy levels.Comparing the two scenarios and following validation by ATCO survey,it is found that capacity estimation considering busy levels is a more realistic and accurate approach.The validated capacity values for the Zhengzhou approach(ZHCC AP)airspace sector accounting for the busy levels were determined accurately as 10 and 33 flights for the 15 min and 1h slices,respectively.The corresponding results without considering busy levels were 12 and 41 flights for the 15 min and 1h time slices,respectively. 展开更多
关键词 ATCO workload airspace sector capacity estimation differentiated routes differentiated busy levels
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Quantization Heat Capacity Equations at Constant Volume According to Energy Levels and Planck Constant
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作者 Daekyoum Kim Youngpak Lee 《American Journal of Analytical Chemistry》 2018年第8期353-365,共13页
The quantization thermal excitation isotherms based on the maximum triad spin number (G) of each energy level for metal cluster were derived as a function of temperature by expanding the binomial theorems according to... The quantization thermal excitation isotherms based on the maximum triad spin number (G) of each energy level for metal cluster were derived as a function of temperature by expanding the binomial theorems according to energy levels. From them the quantized geometric mean heat capacity equations are expressed in sequence. Among them the five quantized geometric heat capacity equations, fit the best to the experimental heat capacity data of metal atoms at constant pressure. In the derivations we assume that the triad spin composed of an electron, its proton and its neutron in a metal cluster become a basic unit of thermal excitation. Boltzmann constant (kB) is found to be an average specific heat of an energy level in a metal cluster. And then the constant (kK) is found to be an average specific heat of a photon in a metal cluster. The core triad spin made of free neutrons may exist as the second one additional energy level. The energy levels are grouped according to the forms of four spins throughout two axes. Planck constant is theoretically obtained with the ratio of the internal energy of metal (U) to total isotherm number (N) through Equipartition theorem. 展开更多
关键词 Statistical Thermodynamics QUANTIZED Heat capacity of Metal Five Energy levels BINOMIAL Theorem BOLTZMANN CONSTANTS PLANCK Constant
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What Is the Relation between Aerobic Capacity and Physical Activity Level in Adults with Congenital Heart Disease?
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作者 Kelly Ferri Maite Doñate +5 位作者 Mireia Parra Guillermo ROviedo Myriam Guerra-Balic Laia Rojano-Doñate Nicole Blackburn Ricard Serra-Grima 《Congenital Heart Disease》 SCIE 2021年第6期585-595,共11页
Background:Aerobic capacity(AC)in adults with congenital heart disease(CHD)is often reduced,mainly due to low confidence levels towards physical activity(PA).The main objective of this study was to estimate the associ... Background:Aerobic capacity(AC)in adults with congenital heart disease(CHD)is often reduced,mainly due to low confidence levels towards physical activity(PA).The main objective of this study was to estimate the association between PA level and AC(measured as peak of oxygen consumption,VO_(2peak))in adults with CHD.Methods:A total of 183 individuals(83 women and 100 men;mean(SD)age 36.9(11.0)years old)from Vall d’Hebron Hospital,Barcelona-Spain in 2019,participated in this cross-sectional study.The AC was assessed by cardiopulmonary exercise testing(CPET)using a treadmill ramp protocol.Considering values of metabolic equivalent of task(MET,MET-min·week-1)obtained by the short International Physical Activity Questionnaire(IPAQ),participants were divided into three categories of PA:health-enhancing PA(HEPA),minimally active,and inactive.Results:Median(SD)PA was 2737.2(2835.7)MET-min·week-1,with 60 participants(32.8%)reporting HEPA,91(49.7%)minimally active,and 32(17.5%)inactivity.Participants demonstrated a mean VO_(2peak) of 28.9(8.8)mL·Kg^(-1)·min^(-1),showing AC values on average 13%lower than expected in a healthy population.Overall,PA and AC were positively associated.Adjusting for sex and age,an increase of 1000 MET-min·week^(-1) was associated with an increase in VO_(2peak) of 0.8 units(95%CI 0.4–1.2;p<0.001).There were no differences in the degree of increase between sexes(p=0.427).Conclusion:These findings suggest that an increase in PA in patients with CHD significantly improves their AC,and hence,could be recommended when the goal is to improve their physical condition. 展开更多
关键词 Physical activity level aerobic capacity congenital heart disease
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Effects of Facial Isometric Exercise on Antioxidant Capacity
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作者 Ikuyo Orita Ikuhiro Morikita +2 位作者 Mayumi Watanabe Zaigen Oh Shigeyuki Kanai 《Health》 2021年第11期1171-1180,共10页
<strong>Background:</strong> Facial isometric exercise is a static contraction of facial muscles without any visible movement in the angle of the joints. To examine the effects of facial isometric exercise... <strong>Background:</strong> Facial isometric exercise is a static contraction of facial muscles without any visible movement in the angle of the joints. To examine the effects of facial isometric exercise on subjective stress and oxidative stress/antioxidant capacity. <strong>Methods:</strong> In this study, we included 13 participants (6 males, 7 females;average age, 44.8 ± 19.6 years;age range: 20 - 74 years) who were exposed to constant temperature and humidity in a room. Fifteen minutes after entering the room, the force was measured before and after facial isometric exercise of the target muscles: upper lip levator, small zygomatic, large zygomatic, levator animus, laughing, buccal, muzzle, mental, temporal, masseter, and cervical muscles), and further evaluated by comparing the facial isometric exercise group and control (non-facial isometric exercise) group (crossover test). <strong>Results:</strong> Subjective stress significantly improved by 8.7 ± 16.3 in the facial isometric exercise group, and no significant difference in oxidative stress level was observed in both the groups. However, the antioxidant capacity significantly increased by 126.8 ± 168.1 μmol/l in the facial isometric exercise group. <strong>Conclusion:</strong> The results of this study suggest that facial isometric exercise is an exercise therapy that can provide mental stability and antiaging effects due to improvement in subjective stress and biological antioxidant potential. 展开更多
关键词 Facial Isometric Exercise Subjective Stress Oxidative Stress levels Antioxidant capacity
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The Influence of LOS Components on the Statistical Properties of the Capacity of Amplify-and-Forward Channels
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作者 Gulzaib RAFIQ Matthias PATZOLD 《Wireless Sensor Network》 2009年第1期7-14,共8页
Amplify-and-forward channels in cooperative networks provide a promising improvement in the network coverage and system throughput. Under line-of-sight (LOS) propagation conditions in such cooperative networks, the ov... Amplify-and-forward channels in cooperative networks provide a promising improvement in the network coverage and system throughput. Under line-of-sight (LOS) propagation conditions in such cooperative networks, the overall fading channel can be modeled by a double Rice process. In this article, we have stud-ied the statistical properties of the capacity of double Rice fading channels. We have derived the analytical expressions for the probability density function (PDF), cumulative distribution function (CDF), level- crossing rate (LCR), and average duration of fades (ADF) of the channel capacity. The obtained results are studied for different values of the amplitudes of the LOS components in the two links of double Rice fading channels. It has been observed that the statistics of the capacity of double Rice fading channels are quite dif-ferent from those of double Rayleigh and classical Rice fading channels. Moreover, the presence of an LOS component in any of the two links increases the mean channel capacity and the LCR of the channel capacity. The validity of the theoretical results is confirmed by simulations. The results presented in this article can be very useful for communication system designers to optimize the performance of cooperative networks in wireless communication systems. 展开更多
关键词 AMPLIFY-AND-FORWARD CHANNELS Channel capacity Cooperative Networks LINE-of-SIGHT Component DOUBLE Rice PROCESS DOUBLE Rayleigh PROCESS level-Crossing Rate Average Duration of Fades
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Integrated reliability of travel time and capacity of urban road network under ice and snowfall conditions 被引量:3
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作者 冷军强 张亚平 +1 位作者 张倩 赵莹萍 《Journal of Central South University》 SCIE EI CAS 2010年第2期419-424,共6页
In order to evaluate and integrate travel time reliability and capacity reliability of a road network subjected to ice and snowfall conditions,the conceptions of travel time reliability and capacity reliability were d... In order to evaluate and integrate travel time reliability and capacity reliability of a road network subjected to ice and snowfall conditions,the conceptions of travel time reliability and capacity reliability were defined under special conditions.The link travel time model(ice and snowfall based-bureau public road,ISB-BPR) and the path choice decision model(elastic demand user equilibrium,EDUE) were proposed.The integrated reliability was defined and the model was set up.Monte Carlo simulation was used to calculate the model and a numerical example was provided to demonstrate the application of the model and efficiency of the solution algorithm.The results show that the intensity of ice and snowfall,the traffic demand and supply,and the requirements for level of service(LOS) have great influence on the reliability of a road network.For example,the reliability drops from 65% to 5% when the traffic demand increases by 30%.The comprehensive performance index may be used for network planning,design and maintenance. 展开更多
关键词 可靠性概念 网络容量 旅行时间 城市道路 时间模型 业务流程再造 蒙特卡罗模拟
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Influence of varied drought types on soil conservation service within the framework of climate change:insights from the Jinghe River Basin,China
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作者 BAI Jizhou LI Jing +4 位作者 RAN Hui ZHOU Zixiang DANG Hui ZHANG Cheng YU Yuyang 《Journal of Arid Land》 SCIE CSCD 2024年第2期220-245,共26页
Severe soil erosion and drought are the two main factors affecting the ecological security of the Loess Plateau,China.Investigating the influence of drought on soil conservation service is of great importance to regio... Severe soil erosion and drought are the two main factors affecting the ecological security of the Loess Plateau,China.Investigating the influence of drought on soil conservation service is of great importance to regional environmental protection and sustainable development.However,there is little research on the coupling relationship between them.In this study,focusing on the Jinghe River Basin,China as a case study,we conducted a quantitative evaluation on meteorological,hydrological,and agricultural droughts(represented by the Standardized Precipitation Index(SPI),Standardized Runoff Index(SRI),and Standardized Soil Moisture Index(SSMI),respectively)using the Variable Infiltration Capacity(VIC)model,and quantified the soil conservation service using the Revised Universal Soil Loss Equation(RUSLE)in the historical period(2000-2019)and future period(2026-2060)under two Representative Concentration Pathways(RCPs)(RCP4.5 and RCP8.5).We further examined the influence of the three types of drought on soil conservation service at annual and seasonal scales.The NASA Earth Exchange Global Daily Downscaled Projections(NEX-GDDP)dataset was used to predict and model the hydrometeorological elements in the future period under the RCP4.5 and RCP8.5 scenarios.The results showed that in the historical period,annual-scale meteorological drought exhibited the highest intensity,while seasonal-scale drought was generally weakest in autumn and most severe in summer.Drought intensity of all three types of drought will increase over the next 40 years,with a greater increase under the RCP4.5 scenario than under the RCP8.5 scenario.Furthermore,the intra-annual variation in the drought intensity of the three types of drought becomes smaller under the two future scenarios relative to the historical period(2000-2019).Soil conservation service exhibits a distribution pattern characterized by high levels in the southwest and southeast and lower levels in the north,and this pattern has remained consistent both in the historical and future periods.Over the past 20 years,the intra-annual variation indicated peak soil conservation service in summer and lowest level in winter;the total soil conservation of the Jinghe River Basin displayed an upward trend,with the total soil conservation in 2019 being 1.14 times higher than that in 2000.The most substantial impact on soil conservation service arises from annual-scale meteorological drought,which remains consistent both in the historical and future periods.Additionally,at the seasonal scale,meteorological drought exerts the highest influence on soil conservation service in winter and autumn,particularly under the RCP4.5 and RCP8.5 scenarios.Compared to the historical period,the soil conservation service in the Jinghe River Basin will be significantly more affected by drought in the future period in terms of both the affected area and the magnitude of impact.This study conducted beneficial attempts to evaluate and predict the dynamic characteristics of watershed drought and soil conservation service,as well as the response of soil conservation service to different types of drought.Clarifying the interrelationship between the two is the foundation for achieving sustainable development in a relatively arid and severely eroded area such as the Jinghe River Basin. 展开更多
关键词 meteorological drought hydrological drought agricultural drought soil conservation service Variable Infiltration capacity(VIC)model Revised Universal Soil Loss Equation(RUSLE) Jinghe River Basin
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Water, Sanitation and Hygiene in Lower-Level Health Care Facilities of Dar es Salaam Region in Tanzania: Status towards Achieving the Sustainable Development Goals and Way Forward
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作者 Mariam Mahamudu Hussein Mohamed +8 位作者 Michael Habtu Dennis Rweyemamu Anyitike Mwakitalima Amour Seleman Erick Mgina Khalid Massa Grace Saguti Andre Arsene Bita Fouda Zabulon Yoti 《Advances in Infectious Diseases》 CAS 2024年第1期279-295,共17页
Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) ... Background: Improving Water, Sanitation and Hygiene in health care settings is a critical prerequisite for achieving national health goals and Sustainable Development Goals (SDGs). The World Health Organization (WHO) has set a target for each United Nations member state to reach by 2030. Each member state is required to reach by 2022, 2025 and 2030 at least 60%, 80% and 100%, respectively of basic level of service of the five elements which are water, sanitation, hygiene, waste management and environmental cleaning. Methods: This study aimed to evaluate and document the current state of basic water, sanitation, and hygiene services in all lower-level health care facilities in the Dar es Salaam region of Tanzania as of July 2022. A cross-sectional study was conducted in 99 public dispensaries in the Dar es Salaam region’s five councils: Ubungo, Kigamboni, Kinondoni and Temeke Municipalities, and Ilala City. The interviewee form and observational checklists were both digitalized using the Kobo tool software. The respondents were health care facility in-charges or nurse in-charges. Data were downloaded, validated, and imported to Stata version 15 for analysis. Results: The basic WASH level per JMP is far below the target in 2022. Each member state by 2022 is required to reach at least 60% of the basic level of service of each element. We found a low coverage of basic WASH in the 99 dispensaries included in this study. The basic WASH coverage was met in only 10 (10.1%) of the dispensaries, while the remaining 89 (89.9%) dispensaries fall on limited WASH services. Conclusion: This study revealed lower coverage of basic WASH services in dispensaries. An urgent need is required to improve the status of WASH in all the dispensaries and facilitate the provision of quality health care services, patient safety and reduce health care associated infections. 展开更多
关键词 Dispensaries Low level Health Care Facilities service levels Basic WASH Dar es Salaam
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Demand and Capacity Modelling in Healthcare Using Discrete Event Simulation 被引量:1
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作者 Saurav Singla 《Open Journal of Modelling and Simulation》 2020年第4期88-107,共20页
The NHS is right now confronting huge pressures relating to demand and capacity in radiology. The purpose of this research has been to provide information about MRI usage, details of operational aspects of MRI service... The NHS is right now confronting huge pressures relating to demand and capacity in radiology. The purpose of this research has been to provide information about MRI usage, details of operational aspects of MRI services, and to ascertain the planning intentions of NHS radiology services to keep up and create MRI capacity. The report expands on using Discrete Event Simulation (DES) to inspect and plan the utilisation of NHS hospital resources for the radiology department to help a 24 hr service that is available to outpatients which will help with diminishing patient waiting time, better resource usage, understanding the capacity and demand. Consequently, this research examines to adjust staff and resources with the demand of the MRI. The research was investigated using DES in various scenarios to find which resources are inactive;patients are treated slowly. DES helped in discovering resource utilisation and outpatient throughout the system. It additionally helped in distinguishing the bottlenecks in patient flow. The DES simulation results demonstrated that time for the outpatient in the system is less and more outpatients have been treated too. There is a higher level of outpatient patients leaving the system under 120 minutes. The report uncovered an MRI report interpretation time. Reception room time and MRI waiting room time are decreased significantly. It additionally exhibited with an expanded outflow of outpatients, resources, for example, MRI capacity and radiographer utilisation expanded. 展开更多
关键词 Discrete Event Simulation (DES) MRI services Simulation RADIOLOGY DEMAND capacity
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Spatial Disparity in Availability of Tuberculosis Diagnostic Services Based on Sector and Level of Care in Nigeria 被引量:1
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作者 Bethrand Odume Sani Useni +12 位作者 Egwuma Efo Degu Dare Elias Aniwada Nkiru Nwokoye Ogoamaka Chukwuogo Chidubem Ogbudebe Michael Sheshi Aminu Babayi Emperor Ubochioma Obioma Chijioke-Akaniro Chukwumah Anyaike Rupert Eneogu Debby Nongo 《Journal of Tuberculosis Research》 CAS 2023年第1期12-22,共11页
Background: Delay in Tuberculosis (TB) diagnosis can contribute to late presentation, severe disease, and continued transmission. KNCV TB Foundation Nigeria through the United States Agency for International Developme... Background: Delay in Tuberculosis (TB) diagnosis can contribute to late presentation, severe disease, and continued transmission. KNCV TB Foundation Nigeria through the United States Agency for International Development (USAID) funded the TB Local Organization Network (LON) 1 and 2 projects that explored the availability of Tuberculosis services based on sector and levels of care. Methods: TB Patient Pathway Analysis was carried out in 14 states comprising 92 facilities. It involved primary, secondary, and tertiary levels of health care in both the public and private sectors. This was a cross-sectional study under program implementation. Proforma was used to collect data on the available TB diagnostic services. Results: In public health facilities, GeneXpert was available at 100% in tertiary facilities in 8 (57%) states;up to 82% in 4 (33%) states, 50% available at secondary facilities in 2 states, and There is none at the primary facilities. Smear microscopy was available at 100% in tertiary facilities in 9 (64%) states and 3 (25%) states have 50% to 82%;secondary -10 (71%) states have > 70% at facilities;primary 1 (7%) state has it in 61% of facilities. Loop-mediated isothermal amplification (TB-LAMP) in tertiary 2 (17%) states have 20% and 100% respectively;secondary 4 (<30%) states have in 1 or 2 facilities;none for primary facilities. In private health facilities, 79% of states have Smear microscopy at both primary and secondary facilities, and only 2 states (14%) at tertiary facilities. Only 1 (7%) state has GeneXpert in all tertiary facilities, 2 (14%) states have secondary facilities, and 4 states in about 1% of facilities. TB LAMP was not available in any tertiary facility, one (7%) state at secondary with coverage of 1%, and 2 (14%) states at primary both with 4% overall facility coverage. Conclusions: There is an inequitable distribution of TB diagnostic services in both sectors and levels of care in Nigeria. TB care and control will improve with enhanced equitable distribution of TB diagnostic services across the health system. 展开更多
关键词 TUBERCULOSIS Diagnostic services DISPARITY SECTOR level NIGERIA
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