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Comparative studies of critical physiological limits and vulnerability to environmental extremes in small ectotherms:How much environmental control is needed?
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作者 Ary A.HOFFMANN Carla M.SGRÒ 《Integrative Zoology》 SCIE CSCD 2018年第4期355-371,共17页
Researchers and practitioners are increasingly using comparative assessments of critical thermal and physiological limits to assess the relative vulnerability of ectothermic species to extreme thermal and aridity cond... Researchers and practitioners are increasingly using comparative assessments of critical thermal and physiological limits to assess the relative vulnerability of ectothermic species to extreme thermal and aridity conditions occurring under climate change.In most assessments of vulnerability,critical limits are compared across taxa exposed to different environmental and developmental conditions.However,many aspects of vulnerability should ideally be compared when species are exposed to the same environmental conditions,allowing a partitioning of sources of variation such as used in quantitative genetics.This is particularly important when assessing the importance of different types of plasticity to critical limits,using phylogenetic analyses to test for evolutionary constraints,isolating genetic variants that contribute to limits,characterizing evolutionary interactions among traits limiting adaptive responses,and when assessing the role of cross generation effects.However,vulnerability assessments based on critical thermal/physiological limits also need to take place within a context that is relevant to field conditions,which is not easily provided under controlled environmental conditions where behavior,microhabitat,stress exposure rates and other factors will differ from field conditions.There are ways of reconciling these requirements,such as by taking organisms from controlled environments and then testing their performance under field conditions(or vice versa).While comparisons under controlled environments are challenging for many taxa,assessments of critical thermal limits and vulnerability will always be incomplete unless environmental effects within and across generations are considered,and where the ecological relevance of assays measuring critical limits can be established. 展开更多
关键词 comparative studies common garden critical limits ECTOTHERMS environmental control thermal limits stress resistance
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A novel environmental control system based on membrane dehumidification
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作者 Yuan Weixing Yang Bo +3 位作者 Guo Binghan Li Xiangping Zuo Yansheng Hu Wenchao 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2015年第3期712-719,共8页
Abstract This paper conducts a simulation study of a novel aircraft environmental control system based on membrane dehumidification (MD-ECS), and compares the system with the up-to-date four-wheel high pressure de-w... Abstract This paper conducts a simulation study of a novel aircraft environmental control system based on membrane dehumidification (MD-ECS), and compares the system with the up-to-date four-wheel high pressure de-water system (4WHPDW-ECS). Mathematical models for the two sys- tems are established, and a system simulation using a numerical technique is performed to analyze and compare the cooling performance of the two systems. Simulation results show that the cooling capacity of MD-ECS is much higher than that of 4WHPDW-ECS under the same working conditions, indicating that the novel system is theoretically feasible and promising. The effects of the sweep ratio of the membrane dehumidifier on the dehumidification and cooling performance of the system is also investigated. 展开更多
关键词 Aircraft Cooling performance environmental control sys-tem High pressure de-water Membrane dehumidificationSweep ratio
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Controlled Environment Agriculture and Its Ability to Mitigate Food Insecurity
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作者 Aubrey Lynn Garcia Mya Alexandria Catherine Griffith +4 位作者 George Paul Buss Xiusheng Yang John L. Griffis Sarah Bauer Ankit Kumar Singh 《Agricultural Sciences》 CAS 2023年第2期298-315,共18页
The research objective of this review is to discuss the rationale that led to the development of Controlled Environment Agriculture (CEA) and investigate this agricultural approach as a potential solution to mitigate ... The research objective of this review is to discuss the rationale that led to the development of Controlled Environment Agriculture (CEA) and investigate this agricultural approach as a potential solution to mitigate the increased pressures on food security. It describes the need for urban cultivation systems using controlled environments and how they can be harnessed to address pressures facing food security. The factors that have contributed to the growth of CEAs, education, environmental justice, and the advantages and disadvantages of growing crops in CEAs in urban areas will be discussed. The article reviews global urban cultivation systems using controlled environments, by identifying the technologies needed to establish them. The practice of CEA is being increasingly adopted worldwide and we describe urban agriculture and compare it with traditional growing systems. Indoor farming systems that integrate into existing urban infrastructure such as vertical farming and plant factories using CEAs are discussed. Indoor farming gives urban areas enhanced access to food sources, but the cost is high, however decreasing due to recent technological advances. The current review extends the literature by incorporating recent research on the topic of agriculture in urban areas and food security. This review seeks to provide additional information regarding the viability of CEA in urban areas. 展开更多
关键词 controlled Environment Agriculture environmental Education environmental Justice Food Deserts Urban Agriculture
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Urban environmental geological problems and its controlling countermeasures in Shandong province,China
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《Global Geology》 1998年第1期15-15,共1页
关键词 Urban environmental geological problems and its controlling countermeasures in Shandong province China
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Environmental effects of groundwater overdraft and its control
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《Global Geology》 1998年第1期19-20,共2页
关键词 environmental effects of groundwater overdraft and its control
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Impact of Environmental Regulation on Industrial Upgrading: Analysis Based on Panel Data of 30 Provinces in China
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作者 Jianqin LI Chongyuan WANG 《Meteorological and Environmental Research》 CAS 2020年第3期21-31,37,共12页
Environmental regulation and industrial upgrading are the key to achieve win-win results for both economy and the environment. After environmental regulation tools are divided into market incentive and command control... Environmental regulation and industrial upgrading are the key to achieve win-win results for both economy and the environment. After environmental regulation tools are divided into market incentive and command control types,based on the provincial-level data of 30 provinces( cities and regions) in China from 2004 to 2016,the impact of environmental regulation on industrial upgrading and its transmission paths are empirically tested through an intermediary effect model. Technological innovation,FDI and capital market development all meet intermediary conditions,and the market incentive type is more dependent on technological innovation,while the command control type is more dependent on FDI and capital market development.The impact of the two environmental regulation tools on industrial upgrading is further studied. The results show that there is an " inverted U-shaped" relationship between the command control type and industrial upgrading,while there is a " U-shaped" relationship between the market incentive type and industrial upgrading,and there are also certain regional differences in the impact of environmental regulation on industrial upgrading. 展开更多
关键词 Command control environmental regulation Market incentive environmental regulation Industrial upgrading Conduction paths Regional differences
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High day and night temperatures impact on cotton yield and quality——current status and future research direction
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作者 SAINI Dinesh K. IMPA S.M. +5 位作者 MCCALLISTER Donna PATIL Gunvant B. ABIDI Noureddine RITCHIE Glen JACONIS S.Y. JAGADISH Krishna S.V. 《Journal of Cotton Research》 CAS 2023年第3期209-225,共17页
Heat waves,and an increased number of warm days and nights,have become more prevalent in major agricultural regions of the world.Although well adapted to semi-arid regions,cotton is vulnerable to high temperatures,par... Heat waves,and an increased number of warm days and nights,have become more prevalent in major agricultural regions of the world.Although well adapted to semi-arid regions,cotton is vulnerable to high temperatures,particularly during flowering and boll development.To maintain lint yield potential without compromising its quality under high-temperature stress,it is essential to understand the effects of heat stress on various stages of plant growth and development,and associated tolerance mechanisms.Despite ongoing efforts to gather data on the effects of heat stress on cotton growth and development,there remains a critical gap in understanding the distinct influence of high temperatures during the day and night on cotton yield and quality.Also,identifying mechanisms and target traits that induce greater high day and night temperature tolerance is essential for breeding climate-resilient cotton for future uncertain climates.To bridge these knowledge gaps,we embarked on a rigorous and comprehensive review of published literature,delving into the impact of heat stress on cotton yields and the consequential losses in fiber quality.This review encompasses information on the effects of heat stress on growth,physiological,and biochemical responses,fertilization,cotton yield,and quality.Additionally,we discuss management options for minimizing heat stress-induced damage,and the benefits of integrating conventional and genomics-assisted breeding for developing heat-tolerant cotton cultivars.Finally,future research areas that need to be addressed to develop heat-resilient cotton are proposed. 展开更多
关键词 controlled environment COTTON Fiber yield and quality Heat stress Heat tents Reproductive failure
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The Assessment of Growth Performance of Brassica rapa var. chinensis ‘Li Ren Choi’, Spinacia oleracea ‘Auroch’, Eruca sativa ‘Astro’, and Brassica rapa var. japonica Using GREENBOX Technology
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作者 George Paul Buss Paige Ann Carroll +6 位作者 Mya Alexandria Catherine Griffith Xiusheng Yang John L. Griffis Jr. Galen Papkov Sarah Bauer Kathryn Jackson Ankit Kumar Singh 《Agricultural Sciences》 2023年第9期1222-1237,共16页
Obtaining nutritious food is becoming increasingly difficult due to the growing urban population and the degradation of soil, water, and air from mechanized and industrialized agricultural techniques. More than half t... Obtaining nutritious food is becoming increasingly difficult due to the growing urban population and the degradation of soil, water, and air from mechanized and industrialized agricultural techniques. More than half the global population resides in urban areas, with not enough surrounding agricultural land to meet food requirements. Food traveling long distances, an average of 1020 miles, has resulted in increased food miles for the average food item in the United States of America, representing wasted resources. The novel GREENBOX technology was invented in response to increasing pressures on food security. Previous studies conducted on GREENBOX technology assessed the technical feasibility of utilizing Lettuce Lactuca sativa ‘Rex Butterhead’. We at the APS Laboratory for Sustainable Food at Florida Gulf Coast University assessed the technical feasibility of growing different leafy green vegetable crops. GREENBOX technology consists of thermally insulated climate-controlled enclosures, an artificial lighting source, a soilless cultivation method (hydroponics), and environmental control modules. We assembled two GREENBOX units to assess the environmental conditions and growth performance of Brassica rapa var. chinensis ‘Li Ren Choi’, Spinach Spinacia oleracea ‘Auroch’, Arugula Eruca sativa ‘Astro’, and Mizuna Brassica Brassica rapa var. japonica. Plugs were cultivated and then transplanted in a randomized manner to the nutrient film technique (NFT) channels, subsequently grown for 30 days to full bloom and ready for harvest. Fertigation was carried out using a standard concentration nutrient solution. Crops were arranged in twelve blocks of four species each. We collected environmental data including daily light integral (DLI, mol/m<sup>2</sup>∙d), temperature (˚C), relative humidity (%), and vapor pressure deficit (VPD, kPa). Collected biomass data included wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (mg/cm<sup>2</sup>). We then derived the Specific Leaf Area (SLA, cm<sup>2</sup>/g). Descriptive statistics were utilized to understand the differences in biomass parameters between the four crops grown. We also compared the performance parameters of our crops with existing peer-reviewed literature and found it superior, if not comparable to commonly found industrial output. We determined that all crops grew to full bloom, demonstrating that GREENBOX technology may be used to grow a variety of different leafy green vegetable crops. 展开更多
关键词 controlled Environment Agriculture Food Insecurity GREENBOX HYDROPONICS LETTUCE
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The Comparative Performance of Nutrient-Film Technique and Deep-Water Culture Method of Hydroponics for GREENBOX Technology
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作者 Mya Alexandria Catherine Griffith George Paul Buss +6 位作者 Paige Ann Carroll Xiusheng Yang John L. Griffis Jr. Galen Papkov Sarah Bauer Kathryn Jackson Ankit Kumar Singh 《Agricultural Sciences》 2023年第8期1108-1120,共13页
With the rising pressures on food security, GREENBOX technology was developed as an avenue for fresh leafy vegetable crop production in urban settings. GREENBOX units were designed to be thermally insulated and climat... With the rising pressures on food security, GREENBOX technology was developed as an avenue for fresh leafy vegetable crop production in urban settings. GREENBOX units were designed to be thermally insulated and climate controlled, with an artificial lighting source that utilized soilless cultivation techniques. Previous studies conducted on GREENBOX technology used the Nutrient Film Technique (NFT);however, various hydroponic methods exist, such as the Deep-Water Culture (DWC) method being the most used. The APS Laboratory for Sustainable Food at Florida Gulf Coast University (FGCU) compared the crop growth performance between DWC and NFT systems using GREENBOX technology. The following study monitored environmental conditions and compared productivity and biomass data of Rex Butterhead Lettuce crops between DWC and NFT systems. We assembled two GREENBOX units using commercially available materials and the standard nutrient solution for fertigation. The crops grown in DWC and NFT were in a 4 × 6 configuration. The DWC and NFT systems were used to grow Lettuce Lactuca sativa “Rex Butterhead” over 30 days to full bloom from prepared plugs grown for 14 days. We collected environmental data including Photosynthetic Photon Flux Density (PPFD, μmol/m<sup>2</sup>∙s), Daily Light Integral (DLI, mol/ m<sup>2</sup>∙d), temperature (˚C), relative humidity (%), and Vapor Pressure Deficit (VPD, kPa). We collected lettuce crop growth data, which included wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (μmol/m<sup>2</sup>). We derived data, including the Specific Leaf Area (SLA, cm<sup>2</sup>/g) and biomass productivity (kg/m<sup>2</sup>), from previously collected data. We used descriptive statistics to present the collected data. A paired t-test was performed to understand the differences in biomass and productivity parameters between the DWC and NFT-grown lettuce crops. Both the DWC and NFT-grown crops could grow lettuce crops to harvest weight at full bloom. Observed data demonstrated that the biomass parameters and productivity did not differ significantly between the two hydroponics techniques. Therefore, we believe both hydroponic methods may be similar in growth performance and may be used in future iterations of GREENBOX design and prove suitable for fresh vegetable crop production in urban settings. 展开更多
关键词 controlled Environment Agriculture Food Insecurity GREENBOX HYDROPONICS LETTUCE
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The Comparative Performance of Soil-Based Systems with Hydroponics
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作者 Paige Ann Carroll George Paul Buss +6 位作者 Mya Alexandria Catherine Griffith Xiusheng Yang John L. Griffis Jr. Galen Papkov Sarah Bauer Kathryn Jackson Ankit Kumar Singh 《Agricultural Sciences》 2023年第8期1087-1097,共11页
Conventional soil-based agriculture is resource-intensive, utilizing large amounts of land and water, thereby placing a strain on Earth’s natural resources. Soil-based agricultural techniques create environmental iss... Conventional soil-based agriculture is resource-intensive, utilizing large amounts of land and water, thereby placing a strain on Earth’s natural resources. Soil-based agricultural techniques create environmental issues such as soil degradation, deforestation, and groundwater pollution from the mass implementation of fertilizers and pesticides. Agricultural crop production using hydroponics has shown promise to be less resource intensive and provide a faster turnaround in crop production. Soilless cultivation using hydroponics promises to relieve some pressure on Earth’s ecosystems and resources by utilizing lesser land and water footprint. The APS Laboratory for Sustainable Food at Florida Gulf Coast University (FGCU) compared the growth of Lettuce Lactuca sativa “Rex Butterhead” crop grown using soil and soilless methods to analyze the growth performance in each setting. Crops grown in the soil-based medium were raised in the FGCU Food Forest, used a mix of soil and potting mix, watered regularly, and followed standard Integrated Pest Management (IPM) practices. Crops grown hydroponically were grown in a thermally insulated grow tent with an artificial lighting source, ventilation, environmental controls, and the Deep-Water Culture (DWC) method. Lettuce plugs were grown for 15 days in controlled environments until two leaves after the cotyledons had developed and were ready for transplant. Plugs were transplanted into a 4 × 6 matrix at the FGCU Food Forest and the DWC growth system. Crops were grown to full bloom and ready for harvest in the soil (60 days) and soilless (30 days) based setups. We collected crop growth data, including wet weight (g), dry weight (g), leaf area (cm<sup>2</sup>), and chlorophyll concentration (μmol/m<sup>2</sup>). From the collected data, we derived the Specific Leaf Area (SLA, cm<sup>2</sup>/g) and biomass productivity (kg/m<sup>2</sup>). Descriptive statistics were used to describe the collected and derived data. We investigated the slopes of regression lines for each growth curve which derived the differences in biomass and productivity parameters between lettuce grown using soil and hydroponics. Both growing methods can grow lettuce crops to full bloom and to adequate harvest weight. The biomass parameters and productivity differ significantly between the growing methods. The lettuce crops grown using hydroponics increase in wet weight statistically and significantly faster than those grown in soil (p < 0.0001). Therefore, we determined that a hydroponic method of crop production may provide better crop output and biomass indicators measured than soil-based growth. 展开更多
关键词 controlled Environment Agriculture HYDROPONICS LETTUCE Soilless Agriculture Urban Agriculture
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Optimization of rhizosphere cooling airflow for microclimate regulation and its effects on lettuce growth in plant factory 被引量:2
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作者 LI Kun FANG Hui +1 位作者 ZOU Zhi-rong CHENG Rui-feng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2021年第10期2680-2695,共16页
In plant factories,the plant microclimate is affected by the control system,plant physiological activities and aerodynamic characteristics of leaves,which often leads to poor ventilation uniformity,suboptimal environm... In plant factories,the plant microclimate is affected by the control system,plant physiological activities and aerodynamic characteristics of leaves,which often leads to poor ventilation uniformity,suboptimal environmental conditions and inefficient air conditioning.In this study,interlayer cool airflow(ILCA)was used to introduce room air into plants’internal canopy through vent holes in cultivation boards and air layer between cultivation boards and nutrient solution surface(interlayer).By using optimal operating parameters at a room temperature of 28℃,the ILCA system achieved similar cooling effects in the absence of a conventional air conditioning system and achieved an energy saving of 50.8% while bringing about positive microclimate change in the interlayer and nutrient solution.This resulted in significantly reduced root growth by 41.7% without a negative influence on lettuce crop yield.Future development in this precise microclimate control method is predicted to replace the conventional cooling(air conditioning)systems for crop production in plant factories. 展开更多
关键词 air movement environmental control MICROCLIMATE water cooling root and shoot growth
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A sleep staging model for the sleep environment control based on machine learning
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作者 Ting Cao Zhiwei Lian +3 位作者 Heng Du Jingyun Shen Yilun Fan Junmeng Lyu 《Building Simulation》 SCIE EI CSCD 2023年第8期1409-1423,共15页
To date,dynamic sleep environment has been attracted the focus of researchers.Owing to the individual difference on sleep phase and thermal comfort,changes in sleep environment should be occupant-centered,and precise ... To date,dynamic sleep environment has been attracted the focus of researchers.Owing to the individual difference on sleep phase and thermal comfort,changes in sleep environment should be occupant-centered,and precise regulation of the environment required current sleep stages.However,few studies connected occupants and the environment through physiological signal-based model of sleep staging.Therefore,this study tried to develop a data driven sleep staging model with higher accuracy through sleep experiments collecting information.Raw database was processed and selected efficiently according to the characteristics of physiological signals.Finally,the sleep staging model with an average accuracy of 93.9%was built,and other mean indicators(precision:82.5%,recall:83.1%,F1 score:82.8%)performed well.The features adopted by model were found to come from different brain regions,and the global brain signals were suggested to play an important role in the construction of sleep staging model.Moreover,the computational processing of physiology signals should consider their characteristics,i.e.,time domain,frequency domain,time-frequency domain and nonlinear characteristics.The model obtained in this study may deliver a credible reference to advance the research on control of sleep environment. 展开更多
关键词 sleep environment sleep staging MODEL physiological signals machine learning environmental control
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An intelligent control method for a large multi-parameter environmental simulation cabin 被引量:12
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作者 Li Ke Liu Wangkai +1 位作者 Wang Jun Huang Yong 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2013年第6期1360-1369,共10页
The structure and characteristics of a large multi-parameter environmental simulation cabin are introduced.Due to the diffculties of control methods and the easily damaged characteristics,control systems for the large... The structure and characteristics of a large multi-parameter environmental simulation cabin are introduced.Due to the diffculties of control methods and the easily damaged characteristics,control systems for the large multi-parameter environmental simulation cabin are diffcult to be controlled quickly and accurately with a classical PID algorithm.Considering the dynamic state characteristics of the environmental simulation test chamber,a lumped parameter model of the control system is established to accurately control the multiple parameters of the environmental chamber and a fuzzy control algorithm combined with expert-PID decision is introduced into the temperature,pressure,and rotation speed control systems.Both simulations and experimental results have shown that compared with classical PID control,this fuzzy-expert control method can decrease overshoot as well as enhance the capacity of anti-dynamic disturbance with robustness.It can also resolve the contradiction between rapidity and small overshoot,and is suitable for application in a large multi-parameter environmental simulation cabin control system. 展开更多
关键词 environmental cabin environmental testing Expert system Fuzzy control Mathematical models Turbines
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GEAR POSITION DECISION METHOD OF AUTOMATED MECHANICAL TRANSMISSION BASED ON FUZZY INFERENCE 被引量:2
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作者 Qin Guihe Zhang Hongkun Lei Yulong Ge Anlin (Jilin University of Technology) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 1999年第1期77-81,共5页
A gear position decision method used in automated mechanical transmission is introduced. The algorithm of the mechod is composed of a driving environment and driver's intention estimator, the shift schedules suit ... A gear position decision method used in automated mechanical transmission is introduced. The algorithm of the mechod is composed of a driving environment and driver's intention estimator, the shift schedules suit for each typical driving environment and driver's intention situation, and an inference ligic to determine the most proper gear position for the present situation. The estimator identifies the driving environment and driver's intention features which are divided into some typical models. Based on the identified results, the algorithm works out the best gear position. It just simulates the course of driver's making gear position decision when driving a automobile with manual transmission. The test results show that the automated mechanical transmission with the method gives less unnecessary shifting and more proper gear position than common shift schedules. 展开更多
关键词 Automatic transmission Gear position decision Driving environment identification Fuzzy logic control
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Effects of light quality on growth and development of cucumber seedlings in controlled environment 被引量:4
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作者 Song Jinxiu Meng Qingwu +1 位作者 Du Weifen He Dongxian 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2017年第3期312-318,共7页
Conventional light sources have been successfully used to cultivate a wide variety of horticultural crops.However,they are of limited use due to uncontrollability of spectra and energy inefficiency.Light-emitting diod... Conventional light sources have been successfully used to cultivate a wide variety of horticultural crops.However,they are of limited use due to uncontrollability of spectra and energy inefficiency.Light-emitting diodes(LEDs)emerged with tremendous potential in controlled environment agriculture due to their energy efficiency,longevity,and spectral specificity,but the effects of different types of LEDs on plant growth and development must be examined.In this study,cucumber(Cucumis sativus L.cv.Zhongnong 26)seedlings were grown under four different lighting treatments that each delivered a photosynthetic photon flux density of 200μmol/m2·s at plant canopy including triphosphate fluorescent lamps(TF),high-frequency fluorescent lamps(HF),white LEDs(WL),and red and blue LEDs(RBL).Cucumber seedlings were grown in a growth chamber at(25.0±1.5)℃with 12-hour light and 12-hour dark for 30 days after sowing,and data were subsequently collected.Seedlings grown under the WL were 45%,12%,and 40%taller than those grown under the TF,HF and RBL,respectively.The leaf area was 23%smaller under the TF than under the HF.The shoot dry weight was 16%-22%lower under the TF than under the other lighting treatments.The transplants grown under the RBL had the lowest root dry weight and root to shoot ratio.The seedling quality index was similar among all the lighting treatments.The LEDs treatment yielded more total dry weight with unit electric power compared to the fluorescent lamps.The chlorophyll content was 13%-15%higher in plants grown under the HF and WL than that under the TF and RBL.Plants grown under the WL and RBL had greater photosynthetic rate,transpiration rate,and stomatal conductance than those grown under the TF and HF.It was concluded that high quality cucumber seedlings can be efficiently produced under the broad-spectrum WL that emit a reasonable amount of blue,green and red light,and the lack of green light and/or high ratio of red to blue light under the RBL may cause undesired plant attributes. 展开更多
关键词 blue light CHLOROPHYLL cucumber seedlings controlled environment gas exchange green light light-emitting diode red light
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Multi-parameter decoupling and slope tracking control strategy of a large-scale high altitude environment simulation test cabin 被引量:7
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作者 Li Ke Liu Wangkai +2 位作者 Wang Jun Huang Yong Liu Meng 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2014年第6期1390-1400,共11页
A large-scale high altitude environment simulation test cabin was developed to accurately control temperatures and pressures encountered at high altitudes. The system was developed to provide slope-tracking dynamic co... A large-scale high altitude environment simulation test cabin was developed to accurately control temperatures and pressures encountered at high altitudes. The system was developed to provide slope-tracking dynamic control of the temperature–pressure two-parameter and overcome the control difficulties inherent to a large inertia lag link with a complex control system which is composed of turbine refrigeration device, vacuum device and liquid nitrogen cooling device. The system includes multi-parameter decoupling of the cabin itself to avoid equipment damage of air refrigeration turbine caused by improper operation. Based on analysis of the dynamic characteristics and modeling for variations in temperature, pressure and rotation speed, an intelligent controller was implemented that includes decoupling and fuzzy arithmetic combined with an expert PID controller to control test parameters by decoupling and slope tracking control strategy. The control system employed centralized management in an open industrial ethernet architecture with an industrial computer at the core. The simulation and field debugging and running results show that this method can solve the problems of a poor anti-interference performance typical for a conventional PID and overshooting that can readily damage equipment. The steady-state characteristics meet the system requirements. 展开更多
关键词 Decoupling control Environment cabin Fuzzy control Liquid nitrogen Mathematical model Vacuum
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Design and experiment of the environment control system for the industrialized production of Agaricus bisporus
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作者 Kaixuan Zhao Xuefeng Zhu +3 位作者 Hao Ma Jiangtao Ji Xin Jin Jingwei Sun 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2021年第1期97-107,共11页
Environment parameters are the main factors affecting the growth and development of Agaricus bisporus.Because of the requirements of environmental conditions for high-efficiency industrialized production of Agaricus b... Environment parameters are the main factors affecting the growth and development of Agaricus bisporus.Because of the requirements of environmental conditions for high-efficiency industrialized production of Agaricus bisporus,equipments for environment control were developed.Based on the variable operating equipment,a multi-factor fuzzy controller was designed to realize the comprehensive control of ambient temperature,humidity,CO2 concentration,and the temperature and moisture of the compost.The test results showed that the temperature control error was less than±0.5°C and the response speed was more than 0.5°C/h;The control error of ambient humidity was less than±2%RH,and the response speed was more than 9%RH per hour;The moistures at different points in compost ranged from 50%to 70%with a standard deviation of 4.04.The control accuracy of environmental CO2 concentration was within 200μmol/mol.The overall performance of the control system was stable and reliable,which could meet the requirements of environment factors for the growth of Agaricus bisporus.The system can provide technical support and reference for the automatic and precise control of the environment during the industrialized production of Agaricus bisporus. 展开更多
关键词 environment control system Agaricus bisporus industrialized production vertical agriculture fuzzy controller DESIGN EXPERIMENT
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Photothermal controls of vegetative dormancy in Poa secunda
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作者 Allen A.Chen Shui-zhang Fei +1 位作者 Andrew W.Lenssen Kenneth J.Moore 《Grassland Research》 2022年第1期43-52,共10页
Background:Summer vegetative dormancy is a desirable trait in cool-season grasses when they are interplanted with annual crops.Sandberg bluegrass(Poa secunda J.Presl.)shows summer dormancy,but the environmental cues t... Background:Summer vegetative dormancy is a desirable trait in cool-season grasses when they are interplanted with annual crops.Sandberg bluegrass(Poa secunda J.Presl.)shows summer dormancy,but the environmental cues that control dormancy remain unknown.Methods:A controlled environment study using temperature and day length combinations of 32.2℃/15 h,26.6℃/14 h,21.1℃/13 h,and 15.5℃/12 h was conducted with P.secunda accessions PI232347,PI639272,and PI232348,and‘Audubon’red fescue as a nondormant control to determine the optimum treatment for dormancy induction.A second study using treatments of 26.6℃/14 h,21.1℃/13 h,and 15.5℃/12 h was conducted to determine the thresholds for dormancy release.A third study used a factorial experiment with two temperatures(32.2℃ and 15.5℃)and two day lengths(15 and 12 h)to differentiate between temperature and day length effects on dormancy induction.Results:Of the four temperature and day length combinations,all except for 15.5℃/12 h resulted in dormancy by the end of 6 weeks,with 32.2℃/15 h inducing dormancy in only 17 days.Of the three treatments for dormancy release,15.5℃/12 h broke dormancy the fastest in all accessions and released the most number of plants from dormancy.Considerable variation existed between accessions for the speed of dormancy release in the 21.1℃/13 h and 26.6℃/14 h treatments.The third study showed that temperature is the primary inducer for summer dormancy,while longer day length may promote dormancy under inductive temperatures.Conclusions:This study identified the optimum photothermal for induction and release of summer dormancy in P.secunda,which will help future studies in elucidating the mechanism of summer dormancy. 展开更多
关键词 controlled environment dormancy induction dormancy release Sandberg bluegrass summer dormancy
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A design framework for a kinetic shading device system for building envelopes
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作者 Felipe Tavares da Silva Julia Cruz Gaspari Veras 《Frontiers of Architectural Research》 CSCD 2023年第5期837-854,共18页
This paper presents a design framework of a shading device applied on a building envelope,with a scheduled automatic activation logic,based on a sun path diagram.This proposal aims to balance the direct sun indoor exp... This paper presents a design framework of a shading device applied on a building envelope,with a scheduled automatic activation logic,based on a sun path diagram.This proposal aims to balance the direct sun indoor exposure by evaluating the envelope area exposed to direct sun rays and the hourly activation rate of shading devices.These procedures are over the parametric modeling and simulation platform using raytracing,structural finite element analysis,and Computer Numerical Control(CNC)prototyping.The design process of building envelopes equipped with kinetic devices can use all these design resources.The kinetic device’s activation logic relies on the feed-forward paradigm,scheduling the activation from the parametric modeling and the sun path diagram,using an angle threshold between the device post and the sun vector as a parameter.The design framework showed the preliminary path to develop shading devices considering the building envelope shape with a feedforward activation logic based on local sun path characteristics. 展开更多
关键词 Kineticarchitecture Shading device Kinetic design environmental control
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Interactive effects of elevation and land use on soil bacterial communities in the Tibetan Plateau 被引量:3
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作者 Yuanyuan YANG Yin ZHOU +5 位作者 Zhou SHI Raphael A.VISCARRA ROSSEL Zongzheng LIANG Haizhen WANG Lianqing ZHOU Wu YU 《Pedosphere》 SCIE CAS CSCD 2020年第6期817-831,共15页
The Tibetan Plateau of China is uniquely vulnerable to the global climate change and anthropogenic disturbances.As soil bacteria exert a considerable influence on the ecosystem function,understanding their response to... The Tibetan Plateau of China is uniquely vulnerable to the global climate change and anthropogenic disturbances.As soil bacteria exert a considerable influence on the ecosystem function,understanding their response to different climates and land-use types is important.Here,we characterized the bacterial community composition and diversity across three major ecosystems(cropland,forest,and grassland)in the Sygera Mountains of Tibet,along a typical elevational gradient(3300–4600 m).The abundance of taxa that preferentially inhabit neutral or weak alkaline soil environments(such as Actinobacteria,Thermoleophilia,and some non-acidophilus Acidobacteria)was significantly greater in the cropland than in the forest and grassland.Furthermore,the diversity of soil bacterial communities was also significantly greater in the cropland than in the forest and grassland.We observed a unimodal distribution of bacterial species diversity along the elevation gradient.The dominant phyla Acidobacteria and Proteobacteria exhibited consistent elevational distribution patterns that mirrored the abundance of their most abundant classes,while different patterns were observed for Acidobacteria and Proteobacteria at the class level.Soil pH was the primary edaphic property that regulated bacterial community composition across the different land-use types.Additionally,soil pH was the main factor distinguishing bacterial communities in managed soils(i.e.,cropland)from the communities in the natural environments(i.e.,forest and grassland).In conclusion,land use(particularly anthropogenic disturbances such as cropping)largely controlled soil environment,played a major role in driving bacterial community composition and distribution,and also surpassed climate in affecting bacterial community distribution. 展开更多
关键词 alpine ecosystem CLIMATE environmental controls PYROSEQUENCING soil microbe
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