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A Cross-Sectional Study on the Impact of Operation Triple Zero (OTZ) Program on Viral Load Suppression amongst Members of the Adolescent Club in 68 Nigerian Army Reference Hospital Yaba Lagos, Nigeria
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作者 Nkechinyere Harrison Ismail Lawal +7 位作者 Yakubu Adamu Kehinde Aribisala Adegbenga Olarinoye Uzoamaka Agbaim Funmilayo Owolabi Dooshima Okonkwo Laura Chittenden Nathan Okeji 《World Journal of AIDS》 2024年第2期35-44,共10页
Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national ... Background: In Nigeria, adolescents and young people (AYP) aged 10 - 24, comprise 22.3% of the population and with HIV prevalence of 3.5%. The AYP living with HIV enrolled at the 68 NARHY, Lagos reflects the national challenges with poor viral suppression. The OTZ program aligns with the UNAIDS 95-95-95 goals. It seeks to empower AYPLHIV to be in charge of their treatment and commit to triple zero outcomeszero missed appointments, zero missed drugs, and zero viral loads. The purpose of the study was to assess the impact of the OTZ program on viral load suppression among members of the adolescent club in 68 NARHY, Lagos. Method: A cross-sectional retrospective study to evaluate the impact of the OTZ program on the viral load of 53 AYP enrolled in the OTZ program between March 2019 to December 2019 was analyzed. The Percentage of viral load suppression before enrollment compared with 6 and 12 months after enrollment into the OTZ program. The AYP is grouped into 10 - 14, 15 - 19, and 20 - 24 years. Activities conducted were peer driven monthly meetings with the AYP during which the adolescents interacted on issues relating to improving their treatment outcomes, healthcare workers reviewed their clinical status, viral load result, provider peer counseling, and caregivers engagement to support adherence to medication and ARV refills. Results: Before OTZ, 81% aged 10 - 14 years, 75% aged 15 - 19 years, and 25% aged 20 - 24 years were virally suppressed (VL less than 1000 copies/ml). Six months after enrollment, 94% were virally suppressed95% aged 10 - 14 years, 96% aged 15 - 19 years, and 66% aged 20-24 years. Twelve months after enrollment, 96% of AYP were virally suppressed100% aged 10-14 years, 93% aged 15 - 19 years, and 100% aged 20 - 24 years. Males viral load (VL) suppression improved from 79% to 96% and 92%, while females VL suppression improved from 69% to 93% and 100% at 6 and 12 months respectively. Conclusion: The OTZ activities contributed to improved viral load suppression in the AYP of the facility. 展开更多
关键词 impact operation Triple Zero ADOLESCENT Viral Load NIGERIA
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Assessment of the Impacts of Thunderstorm on Flight Operations at Murtala Mohammed International Airport,Ikeja,Lagos State,Nigeria
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作者 I.C.Onwuadiochi O.S.Egede A.C.Udeogu 《Journal of Geographical Research》 2023年第1期17-27,共11页
The inefficiency of the aviation industry and the persistent rise in aviation hazards have been linked to weather phenomena.As a result,researchers are looking for better solutions to the problem.The study examined th... The inefficiency of the aviation industry and the persistent rise in aviation hazards have been linked to weather phenomena.As a result,researchers are looking for better solutions to the problem.The study examined the impact of thunderstorms on flight operations at Murtala Mohammed International Airport,Lagos.The data on thunderstorms and flight operations were sourced from Nigerian Meteorological Agency(NiMet)and Nigerian Airspace Management Agency(NAMA)respectively.In order to meet the research target,descriptive statistics(mean,standard deviation,and charts)and inferential statistics(Pearson’s Product Moment Correlation(PPMC)and Regression)were used.The significance level for all inferential analyses was set at 5%(0.05).The study revealed that 77.4%of thunderstorms occurred during the rainy season(April-October)while 22.6%occurred during the dry season(November-March).It also revealed some fluctuating movements of a thunderstorm in the study area.According to the findings,thunderstorms occur most frequently at the airport in June and less frequently in January and December.The study also discovered that thunderstorms at the airport are positively and significantly related to flight delays and cancellations,while the association between flight diversions and thunderstorm occurrence is positive but statistically insignificant.Furthermore,flight delays,flight diversions,and flight cancellations interact positively among themselves.The regression result of the study revealed that a 1%increase in thunderstorm occurrence leads to a 19.4%increase in flight delay,a 7.1%increase in flight cancellation,and a 4.3%increase in flight diversion.As a result,the study presented various regression models that may be utilized to make predictions.The study proposes consistent thunderstorm observation at the airport and steady forecasts using the regression models,based on the findings.However,it further recommends that pilots,air traffic controllers,and meteorologists be trained and retrained so that they can provide better and more efficient services. 展开更多
关键词 THUNDERSTORMS ASSESSMENT impacts Flight operations AIRPORT
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Impact of surgery on the outcome after spinal cord injury – current concepts and an outlook into the future
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作者 Lukas Grassner Doris Maier 《Neural Regeneration Research》 SCIE CAS CSCD 2016年第12期1928-1929,共2页
Traumatic spinal cord injury(SCI)remains a devastating neurological disorder leading to severe consequences for the affected individual and their families.Further,socioeconomic implications should not be neglected a... Traumatic spinal cord injury(SCI)remains a devastating neurological disorder leading to severe consequences for the affected individual and their families.Further,socioeconomic implications should not be neglected as well.Although life expectancy after SCI increased tremendously,therapeutic treatment options remain limited. 展开更多
关键词 impact of surgery on the outcome after spinal cord injury current concepts and an outlook into the future SCI
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Assessing environmental impact:Micro-energy network optimization in a Chinese industrial park
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作者 Guanzhun Cao Chuan Feng +9 位作者 Tong Li Hongjuan Zhang Xiaoyao Guo Wen Li Yanshuang Jia Leping Chen Yuan Xu Qingsong Wang Guifang Chen Xueliang Yuan 《Chinese Journal of Population,Resources and Environment》 2024年第1期68-73,共6页
Micro-energy systems contribute significantly to environmental improvement by reducing dependence on power grids through the utilization of multiple renewable energy sources.This study quantified the environmental imp... Micro-energy systems contribute significantly to environmental improvement by reducing dependence on power grids through the utilization of multiple renewable energy sources.This study quantified the environmental impact of a micro-energy network system in an industrial park through a life cycle assessment using the operation of the micro-energy network over a year as the functional unit and“cradle-to-gate”as the system boundary.Based on the baseline scenario,a natural gas generator set was added to replace central heating,and the light pipes were expanded to constitute the optimized scenario.The results showed that the key impact categories for both scenarios were global warming,fine particulate matter formation,human carcinogenic toxicity,and human non-carcinogenic toxicity.The overall environmental impact of the optimized scenario was reduced by 68%compared to the baseline scenario.A sensitivity analysis of the key factors showed that electricity from the power grid was the key impact factor in both scenarios,followed by central heating and natural gas.Therefore,to reduce the environmental impact of network systems,it is necessary to further optimize the grid power structure.The research approach can be used to optimize micro-energy networks and evaluate the environmental impact of different energy systems. 展开更多
关键词 Micro-energy network Life cycle assessment Optimal operation Environmental impact
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Telecommunications and Energy Infrastructure Sharing: Technical and Socio-Economic Impact Analysis in a Multi-Operator Environment in Burundi
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作者 Apollinaire Bigirimana Jérémie Ndikumagenge +2 位作者 Sami Tabbane Romeo Nibitanga Hassan Kibeya 《Journal of Computer and Communications》 2024年第10期94-111,共18页
The sharing of telecommunications infrastructure and power supply equipment is currently an applicable and very common model for grouping signal transmission and reception equipment and their power supply on the same ... The sharing of telecommunications infrastructure and power supply equipment is currently an applicable and very common model for grouping signal transmission and reception equipment and their power supply on the same site to ensure coverage of fixed, mobile, Internet and radio and television broadcasting networks. This study consists of producing an inventory of telecommunications and energy infrastructure sharing, focusing on the one hand on analyzing the impacts of active and passive sharing of telecommunications infrastructure from a technical point of view, particularly in terms of legal framework, deployment, coverage and exposure to electromagnetic radiation, and on the other hand on identifying the effects of infrastructure sharing from a socio-economic point of view in a multi-operator mobile telephony environment, by indicating the economic value of the revenue generated as a result of infrastructure sharing. Finally, the results will contribute to identify strategies for ensuring maximum deployment and coverage of the country, and for developing the information and communication technologies (ICT) sector in order to contribute to the digital transformation by digitising services using mobile telephony and the Internet in Burundi. 展开更多
关键词 infrastructure Sharing Mobile Telephony Energy Multi-Operators Environment Technical and Socio-Economic impact
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Methods for Integrating Energy Consumption and Environmental Impact Considerations into the Production Operation of Machining Processes 被引量:10
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作者 HE Yan LIU Fei 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2010年第4期428-435,共8页
Energy consumption and environmental impact considerations of machining processes are viewed as important issues for the global trends towards sustainable manufacturing. The existing research of reducing energy consum... Energy consumption and environmental impact considerations of machining processes are viewed as important issues for the global trends towards sustainable manufacturing. The existing research of reducing energy consumption and environmental impacts of machining processes greatly focuses on design and planning activities, but is reasonably sparse for production operation activities. This paper explores a systematic methodology that incorporates energy consumption and environmental impact considerations into the production operation of machining processes. Firstly, the framework of the methodology is proposed to establish the generic procedures for integrating the above considerations in production operation activities. As the two key issues of the framework, the profile index value matrix is determined by valuing the individual quantity of energy consumption and environmental impacts of machining each job on each machine, and the multi-criteria models are constructed by the operational methods. Furthermore, with the guideline of the framework, the specific formulations are modeled by two sub-models for the parallel machine scheduling problem, in which makespan and energy consumption are the optimizing objectives as well as the constraints of environmental impact considerations. The specific formulations provide a practical method to integrate energy consumption and environmental impact considerations into the scheduling activity, and also can serve as a reference to other activities in the production operation. The case study for a batch of jobs, including seven kinds of gears in the machining shop floor, is presented to demonstrate the application of the specific formulations of the methodology. The proposed methodology provides potential opportunities for reducing energy consumption and environmental impacts in machining processes, and helps production managers in decision-making on the issues of energy consumption and environmental impacts in the production operation. 展开更多
关键词 green manufacturing ENERGY environmental impact production operation MACHininG
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Operational impacts to residual stands following ground-based skidding in Hyrcanian Forest, northern Iran 被引量:1
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作者 Meghdad Jourgholami 《Journal of Forestry Research》 SCIE CAS CSCD 2012年第2期333-337,共5页
Hyrcanian (Caspian) Forest in northern Iran has a richness of biological diversity, with endemic and endangered species. The usage of ground-based skidding is well accepted practice for the extraction of timber from... Hyrcanian (Caspian) Forest in northern Iran has a richness of biological diversity, with endemic and endangered species. The usage of ground-based skidding is well accepted practice for the extraction of timber from the forest, but this operation has tended to cause the greatest environmental problems. The aims of the study were to evaluate and comparison of operational impacts, residual stand damage, regeneration, and to quantify these effects such as: the extent of the damage, wounding patterns, size and distribution after logging operations that utilized two different methods: short log and long log. A Timbetjack cable skidder was used and the study location was in the Kheyrud Forest. Post harvesting assessment of damage to the residual stand was compared along skid trail by 100% inventory method and also for the assessment of regeneration damage along winching strips. The results show that along winching strips the percentage of damage to the regeneration was 44% and 36%, while the tree damages along skid trails reached 2.3% and 4.1% in the short log and long log methods, respectively. The greatest average amount of damage to a bole occurred along the first 1 m up from the ground (97%) and also within 4 m of the skidder centerline (80%). These results show that the short log method causes less damage to the residual stand than the longog method. Tree location to skidder trail appears to have a significant effect on the number and height of scars on a tree. Well designed and constructed trails should be wide enough to allow wood extraction from the forest. Damage to the residual stand might be reduced by proper planning and training of logging crews. 展开更多
关键词 operational impacts forest harvesting method residual stand damage regeneration
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A Literature Review on Freeway Traffic Incidents and Their Impact on Traffic Operations 被引量:1
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作者 Md Ahsanul Islam 《Journal of Transportation Technologies》 2019年第4期504-516,共13页
Congestion on the freeway is more frequent due to several traffic incidents, namely traffic accidents, debris on the road, vehicle breakdown, and collision with guardrails than any other incidents. These, in turn, aff... Congestion on the freeway is more frequent due to several traffic incidents, namely traffic accidents, debris on the road, vehicle breakdown, and collision with guardrails than any other incidents. These, in turn, affect the operational performance of the freeway by increasing queue length, volume, and density. Consequently, effective freeway management strategies can help to minimize these impacts. The study investigates and summarizes existing studies to identify the reasons for and effects of the traffic incidents. Attention is given to the available solutions of the freeway traffic incidents management. The ultimate goal of this study is to identify the gaps which are not yet addressed to improve the operational effectiveness of the freeway. This study was conducted through a comprehensive literature review of existing refereed publications, established standards, and formal guidelines. Literature was sought through the Transport Research International Documentation (TRID) database, IEEE Transactions database, and google scholar search engine. Research focusing on freeway traffic incidents is a growing concern in transportation operations, as transportation network performance depends on it. Due to the advancement of technology, emerging vehicle technologies like connected vehicles have the potential to address these problems affecting the US transportation system and revolutionize mobility in the future. The study can serve as a reference for the researchers that are involved in freeway traffic operations. 展开更多
关键词 TRAFFIC incidents FREEWAY inCIDENT Management impactS of incidents operationAL Performance Measurement
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The Impact of Haze Weather on Health: A view to Future 被引量:15
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作者 LU Kai QIN Yu +1 位作者 HE Guang Xue George F.GAO 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 2013年第12期945-946,共2页
In January 2013, China suffered large-scale haze weather four times, affecting 30 cities in all. The average number of haze weather days in many regions was higher than the same period in every year since 1961. PM2.s,... In January 2013, China suffered large-scale haze weather four times, affecting 30 cities in all. The average number of haze weather days in many regions was higher than the same period in every year since 1961. PM2.s, which is defined as fine particulate matter with an aerodynamic diameter of 2.5 micrometers or less, is the main health hazard in the context of haze weather. It can carry large amounts of poisonous and harmful substances, and penetrate deep into the lungs and blood circulation through the respiratory tract, thereby affecting human health. 展开更多
关键词 HAZE A view to future the impact of Haze Weather on Health
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Impact Force Localization and Reconstruction via ADMM-based Sparse Regularization Method
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作者 Yanan Wang Lin Chen +3 位作者 Junjiang Liu Baijie Qiao Weifeng He Xuefeng Chen 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期170-188,共19页
In practice,simultaneous impact localization and time history reconstruction can hardly be achieved,due to the illposed and under-determined problems induced by the constrained and harsh measuring conditions.Although ... In practice,simultaneous impact localization and time history reconstruction can hardly be achieved,due to the illposed and under-determined problems induced by the constrained and harsh measuring conditions.Although l_(1) regularization can be used to obtain sparse solutions,it tends to underestimate solution amplitudes as a biased estimator.To address this issue,a novel impact force identification method with l_(p) regularization is proposed in this paper,using the alternating direction method of multipliers(ADMM).By decomposing the complex primal problem into sub-problems solvable in parallel via proximal operators,ADMM can address the challenge effectively.To mitigate the sensitivity to regularization parameters,an adaptive regularization parameter is derived based on the K-sparsity strategy.Then,an ADMM-based sparse regularization method is developed,which is capable of handling l_(p) regularization with arbitrary p values using adaptively-updated parameters.The effectiveness and performance of the proposed method are validated on an aircraft skin-like composite structure.Additionally,an investigation into the optimal p value for achieving high-accuracy solutions via l_(p) regularization is conducted.It turns out that l_(0.6)regularization consistently yields sparser and more accurate solutions for impact force identification compared to the classic l_(1) regularization method.The impact force identification method proposed in this paper can simultaneously reconstruct impact time history with high accuracy and accurately localize the impact using an under-determined sensor configuration. 展开更多
关键词 impact force identification Non-convex sparse regularization Alternating direction method of multipliers Proximal operators
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The impact of operative timing on clinical outcomes in elderly hip fracture
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作者 王晓伟 《外科研究与新技术》 2011年第2期117-118,共2页
Objective To study the effect of operative timing on clinical outcomes in elderly hip fracture.Methods Two hundred sixty-seven patients with hip fracture were treated from July 2006 to May 2008.The patients who had an... Objective To study the effect of operative timing on clinical outcomes in elderly hip fracture.Methods Two hundred sixty-seven patients with hip fracture were treated from July 2006 to May 2008.The patients who had an operation within 展开更多
关键词 the impact of operative timing on clinical outcomes in elderly hip fracture
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Smart Grids with Intelligent Periphery:An Architecture for the Energy Internet 被引量:24
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作者 Felix F.Wu Pravin P.Varaiya Ron S.Y.Hui 《Engineering》 SCIE EI 2015年第4期436-446,共11页
A future smart grid must fulfill the vision of the Energy Internet in which millions of people produce their own energy from renewables in their homes, offices, and factories and share it with each other. Electric veh... A future smart grid must fulfill the vision of the Energy Internet in which millions of people produce their own energy from renewables in their homes, offices, and factories and share it with each other. Electric vehicles and local energy storage will be widely deployed. Internet technology will be utilized to transform the power grid into an energysharing inter-grid. To prepare for the future, a smart grid with intelligent periphery, or smart GRIP, is proposed. The building blocks of GRIP architecture are called clusters and include an energy-management system (EMS)-controlled transmission grid in the core and distribution grids, micro-grids, and smart buildings and homes on the periphery; all of which are hierarchically structured. The layered architecture of GRIP allows a seamless transition from the present to the future and plug-and-play interoperability. The basic functions of a cluster consist of (1) dispatch, (2) smoothing, and (3) mitigation. A risk-limiting dispatch methodology is presented; a new device, called the electric spring, is developed for smoothing out fluctuations in periphery clusters; and means to mitigate failures are discussed. 展开更多
关键词 smart grid future grid Energy internet energy- management system integrating renewables power system operation power system control distribution automation systems demand-side management
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The New Contribution to the Important Discourse on Human Rights by General Secretary xi Jinping 被引量:1
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作者 刘海年 HU Liang(译) 《The Journal of Human Rights》 2018年第3期263-284,共22页
Under the background of the fact that human rights protection has become an important part of the socialist construction with Chinese characteristics in the new era, and with the international background of the streng... Under the background of the fact that human rights protection has become an important part of the socialist construction with Chinese characteristics in the new era, and with the international background of the strengthened trend of mainstreaming of human rights, Xi Jinping’s series of speeches and the 19 th CPC national Congress reports comprehensively explained the construction of human rights in China and the development of the international human rights. The important discourse on human rights by General Secretary Xi Jinping is people-centered: people’s yearning for a better life is our goal and reveals the source of human rights. Chinese dream is a dream of the country, of the nation, and of everyone in China. The close integration of individual and collective human rights points out that the state and people are important parts of collective human rights and it is an effective response to the "human rights over sovereignty" of Western countries. That there are not the best human rights, but the better ones; fighting for human rights is not always done, but always doing scientifically reveals the operational form of human rights. The right of survival and development is the primary human right; to attach importance to the right of peace conforms to the reality of our country and it has the support of the vast number of developing countries. Building a community with a shared future for human beings is a new vision for the development of the international human rights. only when the perfection and implementation of Constitution and law are paid attention to, and the democratization and legalization of the international human rights cause are promoted, can the guarantee be provided for the realization of human rights. The important discourse on human rights by General Secretary Xi Jinping is guided by Marxism, carries the communist party member’s original intention of serving people and is deeply rooted in the masses of the people. It inherits the theory of "benevolence" and "harmony" in Chinese culture,stands at the height of history and times, and points out the direction for the all-round development of Chinese people and the overall progress of society, and for the liberation of all mankind. This scientific theory is successfully guiding China’s human rights construction constantly towards new achievements and has had a profound and extensive impact on the international human rights cause. 展开更多
关键词 human rights theory the origin of human rights collective human rights operational patterns a community with a shared future for human beings
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A Methodology for Introducing M&V Adjustments during an Energy Retrofit Impact Assessment
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作者 Nikos Sakkas Evangelos Kaltsis 《Open Journal of Energy Efficiency》 2014年第3期77-84,共8页
The assessment of an energy retrofit necessarily requires an energy measurement campaign before (base year energy consumption) and after (post retrofit energy consumption) the retrofit. Only in this way is it possible... The assessment of an energy retrofit necessarily requires an energy measurement campaign before (base year energy consumption) and after (post retrofit energy consumption) the retrofit. Only in this way is it possible to reach a safe conclusion, on the true retrofit impact. In addition, a number of adjustments are necessary to secure that the retrofit impact on energy consumption is effectively isolated, i.e., which we report on the true retrofit impact and not, for example, on external variations, such as a more mild winter. This paper introduces a conceptual framework for taking account, in the retrofit impact assessment, of three external parameters: weather, indoor comfort and space occupancy. The broader strategy behind this work is to develop a comprehensive methodology that would allow a cost efficient, fast and accurate assessment of energy retrofits in buildings. This would allow insight, on the investor side, as to the prudence of his investment and, and in this way, could help the proliferation of the practice of energy retrofits. The adjustment methodology, introduced here, is a first step in this direction. 展开更多
关键词 ENERGY RETROFIT impact Assessment External Parameter Adjustment OCCUPANCY operational RETROFIT
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Water-Level Fluctuations of Urmia Lake: Relationship with the Long-Term Changes of Meteorological Variables (Solutions for Water-Crisis Management in Urmia Lake Basin)
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作者 Mojtaba Zoljoodi Ali Didevarasl 《Atmospheric and Climate Sciences》 2014年第3期358-368,共11页
Urmia Lake in northwest of Iran, through the recent years has been extremely faced with the water crisis. Climate variations and anthropogenic impacts could be two main affiliated factors in this regard. We considered... Urmia Lake in northwest of Iran, through the recent years has been extremely faced with the water crisis. Climate variations and anthropogenic impacts could be two main affiliated factors in this regard. We considered the long term data series of precipitation, temperature and evaporation in monthly and yearly scales in order to compare to water-level values of Urmia Lake. The statistics approaches such as: standard deviation, trend analysis, T test, Pearson and Spearman correlations, liner regression are used to analyze all variables. The results released that the water-level of Urmia Lake along with the precipitation and temperature of the lake’s basin have experienced the periodic changes through 1961 to 2010, as there are some gradual dryness trends on the study area according to precipitation and temperature variations. Urmia Lake periodic water-level fluctuations show more significant correlation to temperature than the precipitation. Whiles, the water-level’s decreasing behavior especially through 1998 to 2010 is more harsh and different than the rate that is considered for precipitation’s decrease and temperature’s increase. Thus, there could be some anthropogenic factors in the basin which produced some supplementary causes to shrink Urmia Lake. Extracting the double precipitation over the basin through introducing and categorizing of atmospheric synoptic systems in order to cloud seeding operation could be one of urgent and innovative solutions to mitigate water crisis in the basin. 展开更多
关键词 Urmia LAKE WATER-LEVEL Fluctuation Climate Variations WATER CRISIS ANTHROPOGENIC impacts Cloud SEEDinG operation
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Impact factors and improvement measures of enviroment quality in cleaning operating room
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作者 陈小娣 《外科研究与新技术》 2011年第4期266-266,共1页
Objective To analyze the factors that impact the environment quality of cleaning operating room and to discuss improvement measurement. Methods Environment bacteria testing results and prevalence of surgical incision ... Objective To analyze the factors that impact the environment quality of cleaning operating room and to discuss improvement measurement. Methods Environment bacteria testing results and prevalence of surgical incision infection in cleaning operating room were retro- 展开更多
关键词 impact factors and improvement measures of enviroment quality in cleaning operating room
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企业ESG表现与商誉减值
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作者 周泽将 王怡晨 雷玲 《经济理论与经济管理》 北大核心 2024年第7期86-102,共17页
作为重要的非财务信息,企业的ESG表现能否应用于识别商誉减值值得关注。本文以2009—2021年中国A股上市公司为研究对象,考察了企业ESG表现与商誉减值的关系。研究发现:(1)ESG表现越好的企业,商誉减值越少,这意味着企业的ESG表现具有商... 作为重要的非财务信息,企业的ESG表现能否应用于识别商誉减值值得关注。本文以2009—2021年中国A股上市公司为研究对象,考察了企业ESG表现与商誉减值的关系。研究发现:(1)ESG表现越好的企业,商誉减值越少,这意味着企业的ESG表现具有商誉减值识别的作用;(2)良好的ESG表现可以视作企业未来业绩乐观、经营风险较小的积极信号,从而预示着较低的商誉减值;(3)在非国有产权性质、机构持股较少、分析师关注度较低的企业中,企业ESG表现与商誉减值的负向关系更加显著;(4)ESG评级分歧会削弱企业ESG表现与商誉减值间的负向关系。本文基于外部信息使用者视角将企业ESG表现与商誉减值联系起来,为有效识别和防范化解商誉减值风险提供了非财务维度的有益启示。 展开更多
关键词 企业ESG表现 商誉减值 未来经营业绩 经营风险
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走行轮失效对单轨车辆安全性及平稳性的影响
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作者 文孝霞 李竞一 +1 位作者 杜子学 杨震 《机械设计与制造》 北大核心 2024年第10期352-358,共7页
单轨车辆走行轮为充气橡胶轮胎,容易因磨耗、穿刺而失气、漏气,导致走行轮失效。走行轮失效对车辆运行安全性及平稳性有重大影响,本文在单轨车辆走行轮动力学模型上进行走行轮失效处理,研究走行轮失效对单轨车辆运行安全性和平稳性的影... 单轨车辆走行轮为充气橡胶轮胎,容易因磨耗、穿刺而失气、漏气,导致走行轮失效。走行轮失效对车辆运行安全性及平稳性有重大影响,本文在单轨车辆走行轮动力学模型上进行走行轮失效处理,研究走行轮失效对单轨车辆运行安全性和平稳性的影响。研究结果表明:空载和满载工况任一走行轮失效以(5~30)km/h速度行驶在半径100m左转弯道时,轮轨力均大于正常行驶工况,运行安全性差;同侧走行轮失效时对运行安全性的规律相同,左侧走形轮失效工况最恶劣;横向平稳性等级合格,垂向平稳性部分合格,建议以10km/h的速度行驶到维修中心。 展开更多
关键词 单轴转向架 单轨车辆 走行轮失效 运行安全性 运行平稳性 影响分析
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智慧化工园区建设现状及未来发展趋势研究
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作者 杨挺 刘厚周 《化学工业》 CAS 2024年第2期61-68,共8页
总结了我国智慧化工园区发展现状,剖析了智慧化工园区建设运行存在的问题,提供了智慧化工园区建设与管理提升建议,展望了智慧化工园区未来发展趋势。
关键词 智慧化工园区研究 运行现状 存在问题 建议 未来趋势
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超深井射孔冲击动载荷引起封隔器断裂失效分析
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作者 练章华 万智勇 +2 位作者 王飞文 赵朝阳 史君林 《天然气工业》 EI CAS CSCD 北大核心 2024年第6期44-51,共8页
中国超深层油气资源丰富,超深井油气开发过程中常采用一体化管柱完成射孔—试油—酸化三联作业,作业过程中超深井射孔冲击动载荷频繁导致封隔器断裂失效。为解决上述问题,基于弹塑性有限元法,结合实际井下测得的射孔管串起爆瞬态冲击动... 中国超深层油气资源丰富,超深井油气开发过程中常采用一体化管柱完成射孔—试油—酸化三联作业,作业过程中超深井射孔冲击动载荷频繁导致封隔器断裂失效。为解决上述问题,基于弹塑性有限元法,结合实际井下测得的射孔管串起爆瞬态冲击动力学载荷边界条件,开展了新疆某地X1井射孔作业RTTS封隔器(全开式挂壁封隔器)—减震器管串瞬态冲击动力学有限元仿真分析,建立了减震器二阶带阻尼的质量—弹簧力学系统模型,从理论上对比分析了双减震器的减震效果与有限元分析结果的可靠性。研究结果表明:(1)在射孔爆轰0.09 s和0.21 s时刻,中心管接头螺纹处分别出现805.4 MPa和925.1 MPa两个应力峰值,超过了管材的屈服强度和抗拉强度,且冲击波引起的交变应力导致局部位置开始发生裂纹失效,裂纹逐渐扩展到整个截面,造成螺纹接头断裂;(2)根据仿真模型计算结果以及中心管结构尺寸分析,发现其螺纹部分结构尺寸偏小,导致峰值应力超过其抗拉强度造成断裂失效;(3)建议采用中心管上部螺纹连接处镦粗2~3 mm的改进方案,其最大应力可降低27%以上,可明显提高结构强度;(4)使用双减震器能有效降低射孔管串上部冲击载荷,理论计算指出双减震器比单减震器的振幅降低约50%,其最大应力降低约42%。结论认为,研究成果可为超深井RTTS封隔器管柱安全射孔作业提供理论和技术支撑,并将有力推动我国超深层油气资源的高效勘探开发。 展开更多
关键词 超深井 射孔作业 封隔器断裂 减震器 公螺纹接头 冲击载荷 数值模拟
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