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Effects of thinning on the understory light environment of different stands and the photosynthetic performance and growth of the reforestation species Phoebe bournei 被引量:2
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作者 Shicheng Su Nianqing Jin Xiaoli Wei 《Journal of Forestry Research》 SCIE EI CAS CSCD 2024年第1期12-28,共17页
Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in... Light levels determine regeneration in stands and a key concern is how to regulate the light environment of different stand types to the requirements of the understory.In this study,we selected three stands typical in south China(a Cryptomeria japonica plantation,a Quercus acutissima plantation,and a mixed stand of both)and three thinning intensities to determine the best understory light environ-ment for 3-year-old Phoebe bournei seedlings.The canopy structure,understory light environment,and photosynthe-sis and growth indicators were assessed following thin-ning.Thinning improved canopy structure and understory light availability of each stand;species composition was the reason for differences in the understory light environ-ment.Under the same thinning intensity,the mixed stand had the greatest light radiation and most balanced spectral composition.P.bournei photosynthesis and growth were closely related to the light environment;all three stands required heavy thinning to create an effective and sustained understory light environment.In a suitable understory light environment,the efficiency of light interception,absorption,and use by seedlings was enhanced,resulting in a higher carbon assimilation the main limiting factor was stomatal conductance.As a shade-avoidance signal,red/far-red radia-tion is a critical factor driving changes in photosynthesis and growth of P.bournei seedlings,and a reduction increased light absorption and use capacity and height:diameter ratios.The growth advantage transformed from diameter to height,enabling seedlings to access more light.Our findings suggest that the regeneration of shade-tolerant species such as P.bournei could be enhanced if a targeted approach to thinning based on stand type was adopted. 展开更多
关键词 THINNING Understory light environment Phoebe bournei Photosynthetic performance Growth performance
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The Influence of Information Technology Investment on the Organizational Performance:The Moderating Role of External Environment
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作者 Zhilin Shi Simon Choong Mun Kwong 《Proceedings of Business and Economic Studies》 2024年第5期37-42,共6页
In the information era,enterprises can enhance organizational performance through advanced information technology.Based on the resource-based view,this paper examines the mechanism by which information technology(IT)i... In the information era,enterprises can enhance organizational performance through advanced information technology.Based on the resource-based view,this paper examines the mechanism by which information technology(IT)investment influences organizational performance,with the external environment as a moderating variable.Using 265 valid samples collected from agricultural enterprises in Shandong province,this study conducts an empirical test through partial least squares structural equation modeling.The results demonstrate that IT investment has a significant positive effect on organizational performance,and the external environment significantly moderates the relationship between IT investment and organizational performance.This research contributes to a deeper understanding of the relationship between IT investment and organizational performance,enriches resource-based theory,expands the research framework on IT investment,and offers guidance for enterprises seeking sustainable growth. 展开更多
关键词 IT investment Organizational performance External environment
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Performance Testing and Analysis of Automotive-Grade CMOS Sensors in Different Environments
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作者 Zhiyu Gao 《Journal of Electronic Research and Application》 2024年第6期200-207,共8页
Automotive-grade Complementary Metal-Oxide-Semiconductor(CMOS)sensors play a crucial role in automotive electronic systems,especially in the context of the rapid development of Advanced Driver Assistance Systems(ADAS)... Automotive-grade Complementary Metal-Oxide-Semiconductor(CMOS)sensors play a crucial role in automotive electronic systems,especially in the context of the rapid development of Advanced Driver Assistance Systems(ADAS)and autonomous driving technologies.Their performance is directly related to the safety and reliability of vehicles.However,automobiles will face a variety of complex environmental conditions during the actual operation,such as high temperature,low temperature,vibration,humidity changes,and light changes,which may have an impact on the performance of CMOS sensors.Therefore,it is of great significance to study the performance of automotive-grade CMOS sensors in different environments. 展开更多
关键词 Automotive-grade CMOS sensor Different environments performance testing
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The Influence of Workplace Environment on Mental Health:A Quantitative and Qualitative Investigation in China
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作者 Zulian Zhang Meiyu Yan Jiaqin Qi 《International Journal of Mental Health Promotion》 2024年第11期957-966,共10页
Background:The demanding nature of nursing,characterized by long hours,high-stress environments,and substantial workloads,can significantly impact nurses’mental health.However,there are limited studies that assessed ... Background:The demanding nature of nursing,characterized by long hours,high-stress environments,and substantial workloads,can significantly impact nurses’mental health.However,there are limited studies that assessed the influence of workplace environment on nursing mental health based on both quantitative and qualitative approaches.Methods:This study aims to comprehensively investigate the multidimensional relationship between the workplace environment and nurses’well-being.This cross-sectional study was based on a sample of 3256 nurses from various healthcare settings in Shandong province,China(2022),who participated in the quantitative phase.For the qualitative phase,a subsample of participants from the quantitative phase was selected(n=200)using purposive sampling to ensure diversity in terms of age,gender,years of experience,and healthcare settings.The mean age was 35.2 years,with 74%female participants.Results:Significant negative correlations were found between leadership support and mental distress,while workload showed negative associations with General Positive Affect and mental health functioning(p<0.05).Multiple linear regression demonstrated the predictive power of workplace dimensions on mental health,with leadership support,teamwork,and organizational culture positively associated with mental health functioning(p<0.05).Thematic analysis underscored the intricate interplay between workplace indicators and mental health dimensions,emphasizing the need for a holistic approach.Conclusion:This study reveals that key workplace factors,including leadership support,teamwork,and organizational culture,play a vital role in enhancing nurse mental health,which is essential for sustaining high-quality patient care and a resilient healthcare workforce. 展开更多
关键词 Workplace environment nurses mental health job-related stress healthcare
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Effects of virtual agents on interaction efficiency and environmental immersion in MR environments
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作者 Yihua BAO Jie GUO +2 位作者 Dongdong WENG Yue LIU Zeyu TIAN 《虚拟现实与智能硬件(中英文)》 EI 2024年第2期169-179,共11页
Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strate... Background Physical entity interactions in mixed reality(MR)environments aim to harness human capabilities in manipulating physical objects,thereby enhancing virtual environment(VEs)functionality.In MR,a common strategy is to use virtual agents as substitutes for physical entities,balancing interaction efficiency with environmental immersion.However,the impact of virtual agent size and form on interaction performance remains unclear.Methods Two experiments were conducted to explore how virtual agent size and form affect interaction performance,immersion,and preference in MR environments.The first experiment assessed five virtual agent sizes(25%,50%,75%,100%,and 125%of physical size).The second experiment tested four types of frames(no frame,consistent frame,half frame,and surrounding frame)across all agent sizes.Participants,utilizing a head mounted display,performed tasks involving moving cups,typing words,and using a mouse.They completed questionnaires assessing aspects such as the virtual environment effects,interaction effects,collision concerns,and preferences.Results Results from the first experiment revealed that agents matching physical object size produced the best overall performance.The second experiment demonstrated that consistent framing notably enhances interaction accuracy and speed but reduces immersion.To balance efficiency and immersion,frameless agents matching physical object sizes were deemed optimal.Conclusions Virtual agents matching physical entity sizes enhance user experience and interaction performance.Conversely,familiar frames from 2D interfaces detrimentally affect interaction and immersion in virtual spaces.This study provides valuable insights for the future development of MR systems. 展开更多
关键词 Mixed reality Virtual agents Interaction performance environmental immersion Virtual environments
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A climatic environmental performance assessment method for ecological city construction:Application to Beijing Yanqi Lake 被引量:1
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作者 FANG Xiao-Yi CHENG Chen +3 位作者 LIU Yong-Hong DU Wu-Peng XIAO Xiao-Jun DANG Bing 《Advances in Climate Change Research》 SCIE CSCD 2015年第1期23-35,共13页
In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches... In contrast to the input perspective for evaluating planning metrics, this research takes the climatic environmental output effects as the starting point for assessing ecological city construction. Based on approaches such as observation data analysis, meteorological model simulation, and remote sensing, a set of climatic environmental performance assessment methods is developed and established. These methods mainly focus on surface ventilation assessment and urban thermal environment assessment. With the Yanqi Lake ecological development demonstration area located in Huairou district, Beijing as an example, the assessment of the local climatic environment before and after the construction are conducted, and relevant policy suggestions for urban planning and construction are presented. The results show that after development, the ventilation capacity will decrease overall and the ventilation potential index will decrease from 0.53 to 0.44. While this is not a large reduction, and is still at a favorable level, the ventilation potential in some local areas will markedly decrease. Furthermore, the thermal environment will become poorer to some extent; the urban heat island(UHI) area and intensity will increase compared with the current situation;continuous heat islands may occur in local areas; the UHI potential index of the core area will rise from 0.0878 to 0.1217(still a favorable level).Therefore, urban surfaces should be carefully developed and arranged during planning. It is suggested that the negative impacts of large areas of urban construction on the local climatic environment in the Yanqi Lake could be mitigated by 1) strengthening the airflow by introducing fresh,cold, northwesterly air via constructed ventilation corridors, 2) increasing the number of ecological cold sources, particularly for water bodies and green belts to prevent the UHI in the southern region of Yanqi Lake from becoming linked with each other, and 3) considering a pre-program before sub-domain and building planning to obtain optimum building locations. Different construction standards should be developed for different ventilation potential and UHI intensity levels. For strong heat island areas, land areas should be reserved to serve as cold sources. 展开更多
关键词 Ecological city construction Ventilation environment Thermal environment performance assessment Yanqi Lake ecological development demonstration area
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Main properties of ultra-high performance fiber reinforced cement composites under couple effect of load and environment
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作者 Saly Fathy 顾春平 孙伟 《Journal of Southeast University(English Edition)》 EI CAS 2012年第2期184-189,共6页
This study aims to reveal the mechanism that how the content of steel fibers and strength grades affect the macro performance of the ultra-high performance fiber reinforced cementitious composite (UHPFRCC) and to st... This study aims to reveal the mechanism that how the content of steel fibers and strength grades affect the macro performance of the ultra-high performance fiber reinforced cementitious composite (UHPFRCC) and to study the UHPFRCC durability under the combined effect of loads and environments. Three types of high and ultra-high performance fiber reinforced cement composites with different strength grades (100, 150, 200 MPa) and different steel fiber volume fractions (0%, 1%, 2%, 3%) are prepared. The main properties of mechanical performance and short-term durability are studied. A preloading frame is designed to apply a four- point load external flexural stress with a stress selection ratio of 0.5 for UHPFRCC150 specimens. The results show that the growth in strength grade with a proper content of steel fiber greatly increases the strength and toughness of the HPFRCC and the UHPFRCC while decreasing the dry-shrinkage ratio. For the loaded specimens, the existence of steel fiber can reduce the negative influence of tensile stress on the Cl- penetration resistance of the UHPFRCC in addition to improving its ability to resist the freeze-thaw damage. 展开更多
关键词 ultra-high performance fiber reinforced cementitious composite couple effect of load and environment mechanical properties DURABILITY
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Analysis of the sealing performance of combined sealing structure under deep-sea high pressure environment 被引量:2
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作者 JIN Yong-ping YI Pan +1 位作者 PENG You-duo WAN Bu-yan 《Marine Science Bulletin》 CAS 2019年第2期36-56,共21页
For the requirement of safe and stable operation,the combined sealing structure was used for reciprocating motion in the deep sea high-pressure environment,and the effects of different seawater depths and shaft moveme... For the requirement of safe and stable operation,the combined sealing structure was used for reciprocating motion in the deep sea high-pressure environment,and the effects of different seawater depths and shaft movement speed on the sealing performance of the combined sealing structure were studied.The change rule of the sealing performance of the combined sealing structure of reciprocating motion under different working conditions is proved.The study shows that in the combined sealing structure of reciprocating movement,the Von Mises stress and the contact stress of the O-ring varies with the direction of the shaft movement.The Von Mises stress and contact stress of the O-ring,the Von Mises stress and the contact stress on each sealing lip of the slip ring gradually increase with the increasing of seawater depths.At the same time,the Von Mises stress of the O-ring which in the process of the shaft upward movement is greater than the shaft downward movement,making the shaft upward movement more likely to cause the O-ring relaxation and fatigue.The shaft movement speed has no significant influence on the Von Mises stress and contact stress of the O-ring.The research results provide theoretical guidance and technical support for the selection and optimization of the geometrical parameters of the combined sealing structure in the deep-sea high-pressure environment. 展开更多
关键词 deep sea high-pressure environment combined sealing structure performance analysis
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Effect of Mental Health Problems on Academic Performance among University Students in Pakistan 被引量:1
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作者 Shagufta Zada Yuefen Wang +1 位作者 Muhammad Zada Fatima Gul 《International Journal of Mental Health Promotion》 2021年第3期395-408,共14页
Scientific interest in student’s mental health experiences has been increasing in the last years due to their influence on students’learning processes,academic performance,and recently,the suicidal news of a student... Scientific interest in student’s mental health experiences has been increasing in the last years due to their influence on students’learning processes,academic performance,and recently,the suicidal news of a student at a private university due to her mental health condition in Lahore Punjab,Pakistan,captured public attention.That incident also shifted researchers and scholars’attention on the much underexplored and tabooed sphere of the broader public health domain.Hence,the current study aimed to explore the relationship between mental health problems and Pakistani university students’academic performance.Participants were 540 senior semester students within the age range of 20–35 years taken from public and private institutes of Pakistan’s major cities,including Lahore,Islamabad,and Peshawar.Descriptive and inferential statistics was employed for data analysis.Pearson Product Moment Correlation,Hierarchical Regression analysis,and Independent sample t-test were used for data analysis in inferential statistics.The results of the study reveal that there is a strong positive association between mental health and improvement in academic performance.Mental health problems negatively affect the academic performance of university students.The findings of the current study were beneficial for shedding light on the ignorant area within the broader public health domain;the results are also helpful in raising awareness for not only students but also the parents and university administration to plan and design effective intervention strategies to provide proper mental health that resultantly promote academic excellence. 展开更多
关键词 mental health academic performance university students Pakistan
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Moderating variables in the relationship between mental toughness and performance in basketball
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作者 Aubrey Newland Maria Newton +2 位作者 Laura Finch Colin R.Harbke Leslie Podlog 《Journal of Sport and Health Science》 SCIE 2013年第3期184-192,共9页
Purpose: This study explored the relationship between mental toughness and college basketball performance, specifically examining possible moderating variables (gender and starting status). Methods: Male and fema... Purpose: This study explored the relationship between mental toughness and college basketball performance, specifically examining possible moderating variables (gender and starting status). Methods: Male and female (n = 197) college basketball players completed the Psychological Performance Inventory-Alternative (PPI-A), a measure of characteristics and skills consistent with mental toughness, and the PERK an objective measure of basketball performance. Results: Findings suggest that basketball performance can be partially predicted by mental toughness and starting status. Males reported greater mental toughness than females. Starters and nonstarters did not differ in mental toughness. Moderated hierarchical regression analysis indicated that mental toughness was related to performance for male players as both a main effect and interaction with starter status. For female players, in contrast, starter status was the only significant predictor of performance. Practitioners are encouraged to foster the psychological skills associated with mental toughness in females and non-starters in basketball. Conclusion: Discussion of the PPI-A as a measure of mental toughness and suggestions for its improvement are explored. A need exists for additional research on mental toughness and objective performance, as performance enhancement is a major impetus for research on mental toughness. Copyright @ 2012, Shanghai University of Sport. Production and hosting by Elsevier B.V. All rights reserved. 展开更多
关键词 BASKETBALL mental toughness Moderating variables performance Psychological performance Inventory-Alternative Psychological skills
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Co-alignment between Environment Risk,Capital Structure,Growth and High-tech Firm Performance
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作者 李延喜 包世泽 《Journal of Southwest Jiaotong University(English Edition)》 2007年第3期236-241,共6页
To examine whether there is a co-alignment relationship between environment risk, capital structure, growth and high-tech firm performance, the environment risk was measured from the viewpoint of environment change, t... To examine whether there is a co-alignment relationship between environment risk, capital structure, growth and high-tech firm performance, the environment risk was measured from the viewpoint of environment change, the long-term debt ratio was adopted as the measure of the capital structure, and the total asset growth and sales growth were chosen to measure the growth of high-tech firms. Regression analysis shows that there is a significant relationship between environment risk, growth and performance of hightech firms measured by the return on equity and cash flow, respectively. 展开更多
关键词 environment risk Capital structure GROWTH Firm performance High-tech firm
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Assessing performance of cross-administrative environment governance based on PSR model:An empirical analysis of the Beijing-Tianjin-Hebei region
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作者 SI Lin-bo LI Xue-ting 《Ecological Economy》 2019年第4期242-256,共15页
As an effective environment governance tool,environment governance performance evaluation is an important content and method to promote the modernization of environment governance system and governance ability.The env... As an effective environment governance tool,environment governance performance evaluation is an important content and method to promote the modernization of environment governance system and governance ability.The environmental pollution of the Beijing-Tianjin-Hebei region has typical cross-administrative characteristics.Based on the analysis of the major environmental pollution problems in the Beijing-Tianjin-Hebei region,according to the international environment governance PSR model,a performance evaluation system that applies to the environment governance of Beijing-Tianjin-Hebei region is established.Meanwhile,the principal component analysis method is applied to conduct an empirical analysis of the environmental governance panel data for the 13 major cities in the Beijing-Tianjin-Hebei region from 2014 to 2016.The results show that most of the cities in the Beijing-Tianjin-Hebei region attach great importance to reduction of emission and pollutants,continuously alleviating the stress of environmental governance.However,the overall improvement of the environment governance performance in Beijing-Tianjin-Hebei region has presented a polarization imbalance.There is a clear tendency for subjective biases in the implementation of environment governance and a lack of comprehensive and systematic governance.According to the environment governance performance evaluation result of Beijing-Tianjin-Hebei region,the cross-administrative regional environment governance should improve the environment governance performance evaluation system as soon as possible,strengthen the consistency of the environment governance objectives,and implement comprehensive and systematic governance for the regional environment. 展开更多
关键词 cross-administrative GOVERNANCE BEIJING-TIANJIN-HEBEI region environment GOVERNANCE performance evaluation PSR model
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The Effects of the Work Environment on the Employees Optimal Performance: A Study of Ebonyi State College of Education, Ikwo
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作者 Uduma Emmanuel Ogbonnia 《Psychology Research》 2021年第9期386-398,共13页
The study sought to investigate the effects of the work environment on the employees’optimal performance in Ebonyi State College of Education,Ikwo,as one of government organizations.The research design for this study... The study sought to investigate the effects of the work environment on the employees’optimal performance in Ebonyi State College of Education,Ikwo,as one of government organizations.The research design for this study was the survey research design to assess the relationship between the work environment and the employee’s performance in Ebonyi State College of Education.Thus,the population of the study comprised all employees of the college.The college which has total staff strength of 493 employees and seven management members making total of 500 was used as the study area.In an attempt to realize the objectives of the study,222 questionnaires were administered to both the management team and the employees of Ebonyi State College of Education.In order to ensure that all the strata of the population were fairly represented and all cases within each stratum had equal chance of being selected,stratified random sampling was used to select a sample of 215 employees and seven members of the management team for this research.A response rate of 78%was achieved.The data collected from both employees and managers was analyzed,using mean and standard deviation to answer the research questions and t-test statistics to test the hypotheses at alpha level of 0.05 significance.It was found that each of the components that define the work environment were statistically significant to performance of the college.However,the social work environment of employees of the college was the most conducive work environment in the institution and the psychological environment of the college was least conducive.In the end,the work environment of the Ebonyi State College of Education,Ikwo,was statistically significant to the performance of employees of the college.It was among other things recommended that for the performance of staff of the college to be enhanced,the college managers must improve its psychological environment so as to improve the psychological health of its employees. 展开更多
关键词 EFFECTS WORK environment employees’performance
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Energy Performance versus Indoor Environment QualitymNon-traditional Form of Elementary Schools Renovation in Terms of Slovak Republic
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作者 Martin Kovac Katarina Knizova 《Journal of Energy and Power Engineering》 2014年第2期257-263,共7页
The content of contribution is to analyse suggested renovation of school building in term of energy performance and indoor environment quality. There were three selected variants of possible reno ration of school buil... The content of contribution is to analyse suggested renovation of school building in term of energy performance and indoor environment quality. There were three selected variants of possible reno ration of school building. At first, it was installation of equipment for heat recovery into existing mechanical ventilation system. There were further evaluated possibilities how to use glass atrium or ground air-heat exchanger in mechanical ventilation system. These suggested variants were analysed in field of energy performance, namely in term of impacts on heat demand for space heating in order to keep required parameters of indoor environment quality according to standard STN EN 15251 (operative temperature, relative air humidity, air change rate). The analysis was elaborated by using energy simulation tool Design Builder in order to evaluate yearlong operation of buildings. 展开更多
关键词 Energy consumption indoor environment school buildings energy performance of building.
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Determination of 17<i>α</i>-Methyltestosterone in Freshwater Samples of Tilapia Farming by High Performance Liquid Chromatography 被引量:3
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作者 Isabel R. Barbosa Sara Lopes +3 位作者 Rhaul Oliveira Inês Domingues Amadeu M. V. M. Soares António J. A. Nogueira 《American Journal of Analytical Chemistry》 2013年第4期207-211,共5页
17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Ther... 17α-methyltestosterone is used to induce the sex reversal of Tilapia sp. to obtain cultures mono-sex to an economically viable. This practice may lead to environmental contamination and problems in human health. Therefore methods need to be developed to detect residues of 17α-methyltestosterone in aqueous matrices. A simple high-performance liquid chromatographic method using ultraviolet detection (245 nm) and testosterone as internal standard has been developed for the monitoring 17α-methyltestosterone in freshwater samples of tilapia aquaculture. The method described involves limited sample preparation as it includes a filtration followed by a single solid-phase extraction step using C18 cartridge. Validation data indicated that the HPLC-UV method for 17α-methyltestosterone determination in the concentration range of 50 - 2000 μg/L provided good linearity, sensitivity, accuracy and precision. Method performance was efficiently applied to monitoring the freshwater samples of fish ponds and the surrounding aquatic channels. 展开更多
关键词 17α-Methyltestosterone High performance Liquid Chromatography environment TILAPIA FARMING
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PROBLEMS AND COUNTERMEASURES FOR RESOURCES DEVELOPMENT AND ENVIRONMENTAL RENOVATION IN THE CONTIGUOUS AREA OF SHANXI,SHAANXI AND INNER MONGOLIA 被引量:1
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作者 Guo Shaoli Commission for Integrated Survey of Natural Resources under Chinese Academy of Sciences and National Planning Committee, Beijing 《干旱区资源与环境》 CSCD 1993年第Z1期415-418,共4页
The studied area consists of 16 counties belonging to 3 provinces or autonomous re-gion, which are Hequ, Baode, Pianguan and Xinxian counties of Shanxi Province; Yulin,Shenmu, Fugu, Hengshan, Jingbian and Dingbian cou... The studied area consists of 16 counties belonging to 3 provinces or autonomous re-gion, which are Hequ, Baode, Pianguan and Xinxian counties of Shanxi Province; Yulin,Shenmu, Fugu, Hengshan, Jingbian and Dingbian counties of Shaanxi Province;Dongsheng, Tuoketuo, Qingshuihe counties and Yijinhuoluo, Dalate, Zhungeer banners 展开更多
关键词 The Contiguous Area of SHANXI SHAANXI and INNER Mongolia Resources Development environ mental RENOVATION
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Implications COVID-19 on Performance and Energy Management in the Production Electricity 被引量:2
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作者 Noor Shakir Mahmood Ahmed Ali Ajmi +3 位作者 Shamsul Sarip Khairur Rijal Jamaludin Hazilah Mad Kaidi Hayati Abdul Talib 《Computers, Materials & Continua》 SCIE EI 2021年第10期895-911,共17页
The COVID-19 pandemic has directly impacted the electric power industry;the energy sector has experienced huge losses in electricity production.These losses have also affected the reliability of communication and empl... The COVID-19 pandemic has directly impacted the electric power industry;the energy sector has experienced huge losses in electricity production.These losses have also affected the reliability of communication and employees’performance,hence destabilizing the electric power system.This article aims at achieving two objectives.First,analyzing the impact of the COVID-19 pandemic on the communication of performance(human error and human factors)and energy management in electricity production.Second,to develop a conceptual framework model to alleviate effects of the pandemic on the power sector and then improve energy management and human performance.This paper involves investigating the influence of the COVID19 pandemic on the global production of electricity in the first quarters of 2019 and 2020.A conceptual model was developed based on a case study.Additionally,to ensure reliability,a variable,namely COVID-19,was used as a moderator to examine the effects of the independent and dependent variables.The results show that scores for the internet of things(IoT)with awareness and communication(A&C)and workplace environment management were high with Cronbach’s alpha value of 0.87 for the IoT and 0.89 for A&C.These numbers are important indicators of factors that could affect performance and energy management and should not be overlooked by the top management.The results also indicate that the pandemic has had a direct effect on the electricity production sector,and the conceptual framework model revealed that COVID-19,as a moderator,has a direct effect on the variables that significantly affect the improvement of both energy management and employee performance.The case study’s results confirm the poor performance in power plant maintenance and operation,in which human error would increase especially in Iraqi power plants that have not yet adopted any internationally recognized standards for energy management.This paper contributes to the literature studying COVID-19’s impact on the electricity sector in two ways:first,by developing a model to assist the electricity production sector mitigating effects of the COVID-19 pandemic,and second,by providing a detailed investigation into the pandemic’s impact on the electricity sector’s global production.The findings are hoped to assist researchers and research centers in understanding the general and specific framework to manage the pandemic’s effects on electricity production. 展开更多
关键词 COMMUNICATION internet of things decision making energy management performance workplace environment
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Tracking Students’ Mental Engagement Using EEG Signals during an Interaction with a Virtual Learning Environment 被引量:2
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作者 Asma Ben Khedher Imène Jraidi Claude Frasson 《Journal of Intelligent Learning Systems and Applications》 2019年第1期1-14,共14页
Monitoring students’ level of engagement during learning activities is an important challenge in the development of tutoring interventions. In this paper, we explore the feasibility of using electroencephalographic s... Monitoring students’ level of engagement during learning activities is an important challenge in the development of tutoring interventions. In this paper, we explore the feasibility of using electroencephalographic signals (EEG) as a tool to monitor the mental engagement index of novice medicine students during a reasoning process. More precisely, the objectives were first, to track students’ mental engagement evolution in order to investigate whether there were particular sections within the learning environment that aroused the highest engagement level among the students, and, if so, did these sections have an impact on learners’ performance. Experimental analyses showed the same trends in the different resolution phases as well as across the different regions of the environments. However, we noticed a higher engagement index during the treatment identification phase since it aroused more mental effort. Moreover statistically significant effects were found between mental engagement and students’ performance. 展开更多
关键词 EEG ENGAGEMENT INDEX Learners’ performance Computer-Based Learning environments
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A Design of Modern Greenhouse Environmental Monitoring System 被引量:1
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作者 Qingsong NIU 《Asian Agricultural Research》 2017年第7期57-60,共4页
Based on the problems in the current greenhouse environmental monitoring system such as difficult connection layout,low flexibility and high costs,this paper builds the greenhouse environmental monitoring system based... Based on the problems in the current greenhouse environmental monitoring system such as difficult connection layout,low flexibility and high costs,this paper builds the greenhouse environmental monitoring system based on wireless sensor network,and designs the sensor nodes and gateway nodes. The sensor nodes of this system are responsible for collecting environmental parameters and sending the data to gateway nodes via wireless sensor network. And the gateway nodes transmit the data to the remote monitoring platform. The microprocessor module of node hardware uses MSP430F149 microprocessor for data processing and control; wireless communication module consists of nRF905 RF chip and peripheral circuit,responsible for transmitting and receiving data; sensor module uses AM2301 sensor for data measurement; the power supply module uses the circuit consisting of LT1129-3. 3,LT1129-5 and Max660 to provide 3. 3 and ± 5V power. The C language development is employed for wireless routing protocol of node and time synchronization algorithm,to achieve node data acquisition and processing,rule forwarding and remote transmission. Remote monitoring software uses NET. ASP,HTML and C# development to provide visual WEB mode remote data management platform for users. The system goes through networking testing in greenhouse in Xining City,and test results show that the system operation is stable and reliable,and the average network packet loss rate is 2. 4%,effectively solving the problems in greenhouse environmental monitoring system and meeting the application requirements of greenhouse cultivation environmental monitoring. 展开更多
关键词 Wireless sensor network Greenhouse environment Wireless monitoring system Network performance
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Evaluation of Daylighting and Thermo-EnergeticPerformance in Administrative Building in the South ofBrazil 被引量:1
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作者 Paula Wrague Moura Celina Maria Britto Correa Eduardo Grala da Cunha 《Journal of Civil Engineering and Architecture》 2020年第1期20-36,共17页
Daylight is a fundamental element to obtain built environments that promote environmental comfort and energy efficiency. However, strategies that enhance the building daylight performance can affect its thermal energe... Daylight is a fundamental element to obtain built environments that promote environmental comfort and energy efficiency. However, strategies that enhance the building daylight performance can affect its thermal energetic performance. In this sense, research that addresses these aspects at the same time is considered essential. The objective of this paper was to evaluate the daylighting and thermal-energetic performance of administrative environments in a public institution, and to propose strategies that will enhance the use of daylight and lower energy consumption. Therefore, for future projects, and considering new buildings, and retrofit, this research will be an important reference. The research was developed through a case study of an administrative building model, in which the characteristics of solar orientation, light shelf use, glass type, and light and dark colors in walls were modified and combined, deriving it into models proposed. The daylighting performance evaluations were performed through dynamic simulation with the Rhinoceros for Diva software, and the thermal-energetic performance evaluations with the EnergyPlus software. The results of the work showed that a suitable solar orientation has a great impact on the automation of daylight and the energy consumption of the evaluated models, followed by the type of glass and the use of the light colors in internal walls, and that the use of artificial lighting with dimerization is fundamental as a complement to the daylight autonomy. For the boundary conditions of the study, the use of light shelves modified neither the daylight performance nor the thermal-energetic performance of the evaluated models. 展开更多
关键词 DAYLIGHTING daylight performance thermal-energetic performance administrative environments.
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