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Effects of temperature, particle size, and air humidity on sensibility of typical high-energetic explosives
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作者 WU Sanzhen FANG Mingkun +3 位作者 WU Xingliang GUO Guangfei WANG Junhong XU Sen 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2024年第3期408-416,共9页
The production and utilization of high-energetic explosives often pose a range of safety hazards,with sensitivity being a key factor in evaluating these risks.To investigate how temperature,particle size,and air humid... The production and utilization of high-energetic explosives often pose a range of safety hazards,with sensitivity being a key factor in evaluating these risks.To investigate how temperature,particle size,and air humidity affect the responsiveness of commonly used high-energetic explosives,a series of BAM(Bundesanstalt für Materialforschung und-prüfung)impact and friction sensitivity tests were carried out to determine the critical impact energy and critical load pressure of four representative high-energetic explosives(RDX,HMX,PETN and CL-20)under different temperatures,particle sizes,and air humidity conditions.The experimental findings facilitated an examination of temperature and particle size affecting the sensitivity of high-energetic explosives,along with an assessment of the influence of air humidity on sensitivity testing.The results clearly indicate that high-energetic explosives display a substantial decline in critical reaction energy when subjected to micrometre-sized particles and an air humidity level of 45%at a temperature of 90℃.Furthermore,it was noted that the critical reaction energy of high-energetic explosives diminishes with an increase in temperature within 25℃−90℃.In the same vein,as the particle sizes of high-energetic explosives increase,so does the critical reaction energy for micrometre-sized particles.High air humidity significantly affects the sensitivity testing of high-energetic explosives,emphasizing the importance of refraining from conducting sensitivity tests in such conditions. 展开更多
关键词 high-energetic explosives temperature particle size air humidity critical reaction energy
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Effects of Land Cover on Soil Temperature,Humidity and Moisture in Phoebe bournei Forest 被引量:9
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作者 吴际友 陈明皋 +5 位作者 董春英 黄小飞 黄明军 程勇 刘球 吴其军 《Agricultural Science & Technology》 CAS 2015年第12期2725-2729,共5页
Under the condition of high temperature, the effects of five cover patterns (clean tillage, film mulching, weed covering, branches and leaves covering and growing grass covering) on soil properties in young Phoebe b... Under the condition of high temperature, the effects of five cover patterns (clean tillage, film mulching, weed covering, branches and leaves covering and growing grass covering) on soil properties in young Phoebe boumei forest were in- vestigated. The results showed that the five cover patterns all showed significant ef- fects on soil properties in young Phoebe bournei forest under the condition of high temperature. Land cover increased land temperature in Phoebe boumei forest. Un- der the film mulching, the land temperature was increased most rapidly with the largest increment. However, weed covering, branches and leaves covering and growing grass covering decreased land temperature. Among them, growing grass covering showed the best cooling effect. The film mulching, weed covering, branch- es and leaves covering and growing grass covering all increased land humidity. The film mulching showed the best moisture-preserving effect in the early period, but in the late period, the humidity in the film mulching treatment group was lower than that in the clean tillage treatment group. Among the five mulching patterns, moisture loss in the film mulching treatment group was slowest and least, followed by those in the weed covering and branches and leaves covering treatment groups, and moisture loss in the growing grass covering treatment group was fastest and most. 展开更多
关键词 Soil management Land cover Land temperature Land humidity Soil moisture
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Study on Temperature and Humidity of Plastic Greenhouse under Different Ventilation Modes in the Yangtze-Huai Region in Hot Season 被引量:1
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作者 孟力力 刘建龙 +3 位作者 柳军 夏礼如 唐玉邦 虞利俊 《Agricultural Science & Technology》 CAS 2016年第12期2885-2888,2900,共5页
In order to analyze the ventilation and cooling performance of single-tunnel plastic greenhouse in Yangtze-Huai region, the effects of two different ventilation modes (side window, side window+roof window) on the t... In order to analyze the ventilation and cooling performance of single-tunnel plastic greenhouse in Yangtze-Huai region, the effects of two different ventilation modes (side window, side window+roof window) on the temperature and humidity of plastic greenhouse were studied. The results showed that the ventilation mode of opening side window and roof window could effectively reduce the temperature and humidity at the plant canopy height, which was conducive to the growth of plant in greenhouse. 展开更多
关键词 Plastic greenhouse temperature humidity Ventilation COOLING
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COMPUTER DECOUPLE CONTROL OF TEMPERATURE AND HUMIDITY IN PREPROCESSING CHAMBER OF AIR-CONDITIONING TEST EQUIPMENT
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作者 陆宏正 盖其祥 《Journal of China Textile University(English Edition)》 EI CAS 1989年第2期29-34,共6页
This paper deals with the application of decouple Control theory to temperature and humidi-ty control in air-conditioning system. The decouple control algorithm for bivariable systems isderived applicablly for air-con... This paper deals with the application of decouple Control theory to temperature and humidi-ty control in air-conditioning system. The decouple control algorithm for bivariable systems isderived applicablly for air-conditioning system. The algorithm is used to design a temperatureand humidity computer control system for the preprocessing chamber of air-conditioning testequipment. The results of the real-time control experiments indicate that the decouple controlalgorithm is feasible, the control quality is improved and high control precision is achieved. 展开更多
关键词 COMPUTER applications COMPUTER controL DECOUPLING temperature controL SYSTEM humidity controL SYSTEM air conditioning controL
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Temperature and Humidity Control in Greenhouses in Desert Areas
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作者 Shigeki Hirasawa Mai Nakatsuka +2 位作者 Kunio Masui Tsuyoshi Kawanami Katsuaki Shirai 《Agricultural Sciences》 2014年第13期1261-1268,共8页
Water consumption can be reduced by using a greenhouse for agriculture in desert areas. We analyzed the effect of control of ventilation, sprinkler water, and solar radiation?shielding on changes of temperature and hu... Water consumption can be reduced by using a greenhouse for agriculture in desert areas. We analyzed the effect of control of ventilation, sprinkler water, and solar radiation?shielding on changes of temperature and humidity in a greenhouse under various desert area conditions. We calculated the changes in temperature and humidity in a greenhouse for a whole day in four seasons, and the calculation results of water consumption with and without a greenhouse were compared. When ventilation, shielding, and sprinkler water were controlled under suitable conditions to grow orchids in a desert area, water consumption in July was only 7% of that without a greenhouse. 展开更多
关键词 temperature control humidity Ventilation SPRINKLER Water HEAT TRANSFER GREENHOUSE DESERT
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Design of greenhouse temperature and humidity wireless control system based on CC3200
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作者 ZHAO Cheng-cheng DING Hai-fei +1 位作者 LIU Wen-yi KANG Xi 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2018年第2期134-139,共6页
Referring to the shortages that the process of traditional greenhouse measurement by using thermometer and hygrometer is complex,the measurement result is not accurate,and the control system operation is cumbersome,a ... Referring to the shortages that the process of traditional greenhouse measurement by using thermometer and hygrometer is complex,the measurement result is not accurate,and the control system operation is cumbersome,a greenhouse temperature and humidity(TH)control system based on CC3200 is designed.The system uses FPGA as the main controller,sends the TH signals to the wireless module CC3200 by controlling DHT22.The proposed system realizes the remote transmission of data and the automatic control of system. 展开更多
关键词 field programmable gate array(FPGA) CC3200 DHT22 temperature and humidity(TH)of greenhouse wireless control
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Design of Expert PID Control System on Temperature and Humidity Verifying Box 被引量:1
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作者 TIAN Ke-lun 《科技视界》 2012年第24期80-82,共3页
This paper briefly introduces the characteristics of structure and optimum design of the hardware of the expert PID control system on temperature and humidity verifying box.Combined Microcontroller technology with exp... This paper briefly introduces the characteristics of structure and optimum design of the hardware of the expert PID control system on temperature and humidity verifying box.Combined Microcontroller technology with expert PID control technology and with regular construction of temperature-humidity expert control system,the paper sets up the expert control rules,as well as a subset of control flow. 展开更多
关键词 英语教学 教学方法 阅读教学 英语翻译
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Impact of Variegated Temperature, CO<SUB>2</SUB>and Relative Humidity on Survival and Development of Beet Armyworm <i>Spodoptera exigua</i>(Hubner) under Controlled Growth Chamber
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作者 Jagdish Jaba Suraj Prashad Mishra +1 位作者 Naveen Arora Rajendra Munghate 《American Journal of Climate Change》 2020年第4期357-370,共14页
Climate change will have a noteworthy bearing on survival, development, and population dynamics of insect pests. Therefore, we contemplated the survival and development of beet army worm, <em>Spodoptera exigua&l... Climate change will have a noteworthy bearing on survival, development, and population dynamics of insect pests. Therefore, we contemplated the survival and development of beet army worm, <em>Spodoptera exigua</em> under different temperatures, (15<span style="white-space:nowrap;">&#176;</span>C, 25<span style="white-space:nowrap;">&#176;</span>C, 35<span style="white-space:nowrap;">&#176;</span>C, and 45<span style="white-space:nowrap;">&#176;</span>C), CO<sub>2</sub> (350, 550, 750 ppm) and relative humidity (55%, 65%, 75% and 85%) regimes. Maximum larval and pupal weights were recorded in insects reared at 25<span style="white-space:nowrap;">&#176;</span>C. The growth of <em>S. exigua</em> was faster at 35<span style="white-space:nowrap;">&#176;</span>C (larval period 7.4 days and pupal period 4.5 days) than at lower temperatures. At 15<span style="white-space:nowrap;">&#176;</span>C, the larval period was extended for 61.4 days and there was no adult emergence from the pupae till 90 days. The <em>S. exigua</em> hatchling was absent at 45<span style="white-space:nowrap;">&#176;</span>C. The larval survival ranged from 31.6% - 57.2%, maximum survival was recorded at 25<span style="white-space:nowrap;">&#176;</span>C, and minimum at 45<span style="white-space:nowrap;">&#176;</span>C. The maximum (84.27%) and minimum adult emergence were recorded in insects reared at 25<span style="white-space:nowrap;">&#176;</span>C and 35<span style="white-space:nowrap;">&#176;</span>C respectively. Maximum fecundity (384.3 eggs/female) and egg viability (51.97%) were recorded in insects reared at 25<span style="white-space:nowrap;">&#176;</span>C. Larval and pupal periods increased with an increase in CO<sub>2</sub> concentration. The highest pupal weights (128.6 mg/larva) were recorded at 550 ppm. The highest larval survival (73.50%) was recorded at 550 ppm and minimum (37.00%) at 750 ppm CO<sub>2</sub>. Fecundity was the highest in insects reared at 550 ppm CO<sub>2</sub> (657.4 eggs/female), and the lowest at 750 ppm. Maximum larval and pupal weights were recorded in insects reared at 75% relative humidity (RH). The growth rate of<em> S. exigua</em> was faster at 85% RH than at lower RH. The larval survival ranged between 40.0% - 58.5%. Maximum adult emergence (88.91%) was recorded in insects reared at 75% RH and minimum at 85% RH. Maximum fecundity (447.6 eggs/female) and the highest egg viability (72.95%) were recorded in insects reared at 75% and 65% RH respectively. Elevated temperatures and relative moistness will diminish the life cycle, while hoisted CO<sub>2</sub> will drag the life expectancy. Therefore, there is a need for thorough assessment of the impact of climatic factors on the population dynamics of insect pests, crop losses, and sustainability of crop production. 展开更多
关键词 Spodoptera exigua temperature CO2 Relative humidity and Climate Change
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Temperature and Humidity Control System Identification Based on Neural Network in Heating and Drying System
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作者 Zhang Xiaowei 《International Journal of Technology Management》 2014年第7期81-85,共5页
Artificial neural network has unique advantages for massively parallel processing, distributed storage capacity and self-learning ability. The paper mainly constructs neural network identifier and neural network contr... Artificial neural network has unique advantages for massively parallel processing, distributed storage capacity and self-learning ability. The paper mainly constructs neural network identifier and neural network controller for system identification and control on temperature and hmnidity of heating and drying system of materials. And the paper introduces the structure and principles of neural network, and focuses on analyzing learning algorithm, training algorithm and limitation of the most widely applied multi-layer feed-forward neural network ( BP network) , based on which the paper proposes introducing momentum to improve BP network. 展开更多
关键词 neural network BP algorithm material heating and drying temperature humidity
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Effects of Extreme Air Temperature and Humidity on the Insecticidal Expression Level of Bt Cotton 被引量:13
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作者 CHENYuan WEN Yu-jin +5 位作者 CHEN Yuan John Tom Cothren ZHANG Xiang WANG Yong-hui WilliamA Payne CHEN De-hua 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2012年第11期1836-1844,共9页
The higher survival rates of Helicoverpa amigera larvae were usually observed after adverse climate which was related to extreme temperature (T) and relative humidity (RH) stresses in transgenic Bacillus thuringie... The higher survival rates of Helicoverpa amigera larvae were usually observed after adverse climate which was related to extreme temperature (T) and relative humidity (RH) stresses in transgenic Bacillus thuringiensis (Bt) cotton. The unstable resistance of Bt cotton to bollworms has been correlated with the reduced expression of CrylAc δ-endotoxin. The objective of this study was to investigate the effects of combined temperature and relative humidity stresses on the leaf CrylAc insecticidal protein expression during critical developmental stages. The study was undertaken on two transgenic cotton cultivars that share same parental background, Sikang 1 (a conventional cultivar) and Sikang 3 (a hybrid cultivar), during the 2007 and 2008 growing seasons at the Yangzhou University Farm, Yangzhou, China. The study was arranged with two factors that consisted of temperature (two levels) and relative humidity (three levels). The six T/RH treatments were 37℃/95%, 37℃/70%, 37℃/50%, 18℃/95%, 18℃/70%, and 18℃/50%. In 2007, the six treatments were imposed to the plants at peak flowering stage for 24 h; in 2008, the six treatments were applied to the plants at peak square, peak flowering, and peak boll stages for 48 h. The results of the study indicated that the leaf insecticidal protein expression in CrylAc was significantly affected by extreme temperature only at peak flowering stage, and by both extreme temperature and relative humidity during boll filling stage. The greatest reductions were observed when the stresses were applied at peak boll stage. In 2008, after 48 h stress treatment, the leaf Bt endotoxin expression reduced by 25.9-36.7 and 23.6-40.5% at peak boll stage, but only by 14.9-26.5 and 12.8-24.0% at peak flowering stage for Sikang 1 and Sikang 3, respectively. The greatest reduction was found under the low temperature combined with low relative humidity condition for both years. It is believed that the temperature and relative humidity stresses may be attributed to the reduced efficacy of Bt cotton in growing conditions in China, where extreme temperatures often increase up to 35-40℃ and/or decrease down to 15-20℃, and relative humidity may reach to 85-95% and/or reduce to 40-55% during the cotton growing season. 展开更多
关键词 Bt cotton high temperature low temperature relative humidity CryIAc protein
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Spatial distribution of air temperature and relative humidity in the greenhouse as affected by external shading in arid climates 被引量:9
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作者 Hesham AAhmed TONG Yu-xin +2 位作者 YANG Qi-chang Abdulellah AAl-Faraj Ahmed MAbdel-Ghany 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第12期2869-2882,共14页
The effect of external roof shading on the spatial distribution of air temperature and relative humidity in a greenhouse(Tin and RHin) was evaluated under the arid climatic conditions of Riyadh City, Saudi Arabia. Two... The effect of external roof shading on the spatial distribution of air temperature and relative humidity in a greenhouse(Tin and RHin) was evaluated under the arid climatic conditions of Riyadh City, Saudi Arabia. Two identical, evaporatively-cooled, single-span greenhouses were used in the experiment. One greenhouse was externally shaded(Gs) using a movable black plastic net(30% transmissivity), and the other greenhouse was kept without shading(Gc). Strawberry plants were cultivated in both greenhouses. The results showed that the spatial distribution of the Tin and RHin was significantly affected by the outside solar radiation and evaporative cooling operation. The regression analysis showed that when the outside solar radiation intensity increased from 200 to 800 W m–2, the Tin increased by 4.5℃ in the Gc and 2℃in the Gs, while the RHin decreased by 15% in the Gc and 5% in the Gs, respectively. Compared with those in the Gc, more uniformity in the spatial distribution of the Tin and RHin was observed in the Gs. The difference between the maximum and minimum Tin of 6.4℃ and the RHin of 10% was lower in the Gs than those in the Gc during the early morning. Around 2℃ difference in the Tin was shown between the area closed to the exhausted fans and the area closed to the cooling pad with the external shading. In an evaporatively-cooled greenhouse in arid regions, the variation of the Tin and RHin in the vertical direction and along the sidewalls was much higher than that in the horizontal direction. The average variation of the Tin and RHin in the vertical direction was 5.2℃ and 10% in the Gc and 5.5℃ and 13% in the Gs, respectively. The external shading improved the spatial distribution of the Tin and RHin and improved the cooling efficiency of the evaporative cooling system by 12%, since the transmitted solar radiation and accumulated thermal energy in the greenhouse were significantly reduced. 展开更多
关键词 GREENHOUSE temperature humidity distribution UNIFORMITY EVAPORATIVE cooling SHADING ARID climate
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Circadian Rhythm of Calling Behavior in the Emei Music Frog(Babina daunchina) is Associated with Habitat Temperature and Relative Humidity 被引量:12
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作者 Jianguo CUI Xiaoyan SONG +3 位作者 Guangzhan FANG Fei XU Steven E. BRAUTH Yezhong TANG 《Asian Herpetological Research》 SCIE 2011年第3期149-154,共6页
Generally, the function of vocalizations made by male anurans are to attract females or defend resources. Typically, males vocalize in choruses during one or more periods in a twenty-four-hour cycle, which varies, how... Generally, the function of vocalizations made by male anurans are to attract females or defend resources. Typically, males vocalize in choruses during one or more periods in a twenty-four-hour cycle, which varies, however, among species. Nevertheless, the causal factors influencing circadian variations of calling patterns in anuran species are not clear. In this study, male chorus vocalizations were monitored in the Emei music frog(Babina daunchina) for 17 consecutive days during the breeding season, while its habitat air temperature and relative humidity in the course of experiments were measured as well. The results revealed that the circadian calling patterns were characterized by two periods of peak vocalization, which were observed from 0500 h to 0700 h and from 1300 h to 2000 h, while the lowest activity period was found from 2100 h to 2200 h. Both calls/h and notes/h were positively correlated with air temperature and negatively with relative humidity. Overall, our data indicate that the Emei music frogs(B. daunchina) could regulate their vocal activities based on the changes of physical micro-environment(e. g., temperature or humidity) to maximize reproductive success. 展开更多
关键词 rest-activity cycle advertisement call temperature humidity Emei music frog(Babina daunchina
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Tomato Leaf Photosynthetic Responses to Humidity andTemperature Under Salinity and Water Deficit 被引量:12
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作者 H.L.XU L.GAUTHIER 《Pedosphere》 SCIE CAS CSCD 1999年第2期105-112,共8页
Greenhouse tomato plants (Lycopersicon esculentum Mill cv. Capello) were grown on peat-based substrate and treated with high (4.5 mS cm-1) and low (2.3 mS cm-1) nutrient solution electric conductivity(EC) under high a... Greenhouse tomato plants (Lycopersicon esculentum Mill cv. Capello) were grown on peat-based substrate and treated with high (4.5 mS cm-1) and low (2.3 mS cm-1) nutrient solution electric conductivity(EC) under high and low substrate water contents. FOur weeks after the beginning of the treatments, photosynthesis (Th) was measured under different humidity and temperatures to examine the interactive effectswith rhizosphere salinity and water deficit. A rectangular hyperbolic model fitted the light-photosynthesiscurve. Photosynthetic capacity (PC) was decreased but quantum yield (YQ) was increased by rhizospheresalinity caused by high EC. PN was decreased by low humidity only in high EC- and/or water-stressed plants.Under high photosynthetic photon flux (PPF), low humidity induced PC decline in water-stressed plants andPN oscillation in high-EC-treated plants. PN increased steadily as the leaf temperature changed from 18 Cto 23 and then decreased steadily from 23 to 38 . At 34 , PN decreased significantly in waterstressed plants. Dark respiration (RD) increased in an exponential manner as the leaf temperature changedfrom 18 to 38 to an extent about ten times higher under 38 than under 18 . Our data suggestedthat PN decrease under high temperature was attributed, st least in part, to the increased RD. RD in highEC- and/or water-stressed plants was higher than that in the plants of control under lower temperature butlower than that in the plants of control under high temperature. The analysis of stomatal and mesophyllconductance showed that low humidity effect was mainly through stomatal response while temperature effectwas mainly through biochemical functions. The result showed that environmental stresses affected PN in anadditive or synergistic manner. 展开更多
关键词 humidity PHOTOSYNTHESIS rhizosphere salinity temperature water stress
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Seasonal Variation in Air Temperature and Relative Humidity on Building Areas and in Green Spaces in Beijing, China 被引量:10
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作者 KUANG Wenhui 《Chinese Geographical Science》 SCIE CSCD 2020年第1期75-88,共14页
The cooling and humidifying effects of urban parks are an essential component of city ecosystems in terms of regulating microclimates or mitigating urban heat islands(UHIs).Air temperature and relative humidity are tw... The cooling and humidifying effects of urban parks are an essential component of city ecosystems in terms of regulating microclimates or mitigating urban heat islands(UHIs).Air temperature and relative humidity are two main factors of thermal environmental comfort and have a critical impact on the urban environmental quality of human settlements.We measured the 2-m height air temperature and relative humidity at the Beijing Olympic Park and a nearby building roof for more than 1 year to elucidate seasonal variations in air temperature and relative humidity,as well as to investigate the outdoor thermal comfort.The results showed that the lawn of the park could,on average,reduce the air temperature by(0.80±0.19)℃,and increase the relative humidity by(5.24±2.91)% relative to the values measured at the building roof during daytime.During the nighttime,the lawn of the park reduced the air temperature by(2.64±0.64)℃ and increased the relative humidity by(10.77±5.20)%.The park was cooler and more humid than surrounding building area,especially in night period(more pronounced cooling with 1.84℃).Additionally,the lawn of the park could improve outdoor thermal comfort through its cooling and humidifying effects.The level of thermal comfort in the park was higher than that around the building roof for a total of 11 days annually in which it was above one or more thermal comfort levels(average reduced human comfort index of 0.92)except during the winter. 展开更多
关键词 air temperature relative humidity outdoor thermal comfort urban park planning
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Effects of Temperature,Humidity and Different Rice Growth Stages on Vertical Migration of Aphelenchoides besseyi 被引量:7
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作者 SUN Min-jie LIU Wei-hong LIN Mao-song 《Rice science》 SCIE 2009年第4期301-306,共6页
The vertical migration of Aphelenchoides besseyi under different temperatures and humidities and at different rice growth stages was investigated. It was found that the optimum temperature for the development and repr... The vertical migration of Aphelenchoides besseyi under different temperatures and humidities and at different rice growth stages was investigated. It was found that the optimum temperature for the development and reproduction of A. besseyiwas 25-30℃. At the same temperature, the rate of vertical migration increased with rising relative humidity. Artificial inoculation tests showed that at the elongation stage, nematodes survived mainly on the upper and middle parts of rice culms and the number of nematodes decreased by 50% at 20 days after inoculation compared with that at 5 days after inoculation. Whereas at the booting stage, nematodes accumulated in young panicles and reproduced quickly,, and the average number of nematodes at 20 days after inoculation increased to 164.5, three times of that at 5 days after inoculation. 展开更多
关键词 Aphelenchoides besseyi RICE growth stage temperature humidity vertical migration DISTRIBUTION
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Visco-elastic-plastic model of deep underground rock affected by temperature and humidity 被引量:9
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作者 GAO, Yanan GAO, Feng +1 位作者 ZHANG, Zhizhen ZHANG, Tao 《Mining Science and Technology》 EI CAS 2010年第2期183-187,共5页
As the depth of exploitation increases,studies on constitutive models of rock affected by temperature and humidity become very important.Based on the Nishihara model,a visco-elastic-plastic rock model was established ... As the depth of exploitation increases,studies on constitutive models of rock affected by temperature and humidity become very important.Based on the Nishihara model,a visco-elastic-plastic rock model was established by using the coefficients of thermal and humidity expansion,thermal viscosity attenuation,humid viscosity attenuation and acceleration rheology components.We used the definition of a controlled heat circle to explain the model.The results show that the behavior of rock,affected by temperature and humidity,is stable as a function of time when the stress is lower than the first yield stress σS1;the creep rate will increase due to the effect of temperature and humidity when the stress is greater than or equal to σS1;the creep rate will accelerate at an increasing rate when the stress is greater than or equal to the second yield stress σS2,which results in a failure of the roadway.The model derived in this study can completely describe visco-elastic-plastic characteristics and reflects the three stages of rock creep. 展开更多
关键词 temperature humidity CREEP controlled heat circle
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Local Variability in Temperature, Humidity and Radiation in the BaekduDaegan Mountain Protected Area of Korea 被引量:5
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作者 CHAE Heemun LEE Hyunju +4 位作者 LEE Sangsin CHEONG Yukyong UM Gijeung MARK Bryan PATRICK Nathan 《Journal of Mountain Science》 SCIE CSCD 2012年第5期613-627,共15页
A novel embedded sensor network records changes in key climatic-environmental variables over a range of altitude in the BaekduDaegan Mountain (BDM) of Gangwon Province in Korea, a protected mountain region with uniq... A novel embedded sensor network records changes in key climatic-environmental variables over a range of altitude in the BaekduDaegan Mountain (BDM) of Gangwon Province in Korea, a protected mountain region with unique biodiversity undergoing climate change research. The investigated area is subdivided into three horizontal north-south study areas. Three variables, temperature (T, °C), relative humidity (RH, %), and light intensity (LI, lumens m-2, or lux, lx), have been continuously measured at hourly intervals from June, 2olo to September, 2011 using HOBO H8 devices at lO fixed study sites. These hourly observations are aggregated to monthly, seasonal and annual mean values, and results are summarized to inaugurate a long-term climate change investigation. A region wide T difference in accordance with altitude, or lapse rate, over the interval is calculated as o.4°C l00 m-1. T lapse rates change seasonally, with winter lapse rates being greater than those of summer. RH is elevated in summer compared to other seasons. LI within forestland is lower during summer and higher during other seasons. The obtained results could closely relate to the vegetation type and structure and the terrain state since data loggers were located in forestland. 展开更多
关键词 Embedded sensors temperature lapserates Relative humidity Light intensity FOREST Climate change BaekduDaegan Mountain
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One-Dimensional Variational Retrieval of Temperature and Humidity Profiles from the FY4A GIIRS 被引量:4
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作者 Qiumeng XUE Li GUAN Xiaoning SHI 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第3期471-486,共16页
A physical retrieval approach based on the one-dimensional variational(1 D-Var) algorithm is applied in this paper to simultaneously retrieve atmospheric temperature and humidity profiles under both clear-sky and part... A physical retrieval approach based on the one-dimensional variational(1 D-Var) algorithm is applied in this paper to simultaneously retrieve atmospheric temperature and humidity profiles under both clear-sky and partly cloudy conditions from FY-4 A GIIRS(geostationary interferometric infrared sounder) observations. Radiosonde observations from upper-air stations in China and level-2 operational products from the Chinese National Satellite Meteorological Center(NSMC)during the periods from December 2019 to January 2020(winter) and from July 2020 to August 2020(summer) are used to validate the accuracies of the retrieved temperature and humidity profiles. Comparing the 1 D-Var-retrieved profiles to radiosonde data, the accuracy of the temperature retrievals at each vertical level of the troposphere is characterized by a root mean square error(RMSE) within 2 K, except for at the bottom level of the atmosphere under clear conditions. The RMSE increases slightly for the higher atmospheric layers, owing to the lack of temperature sounding channels there.Under partly cloudy conditions, the temperature at each vertical level can be obtained, while the level-2 operational products obtain values only at altitudes above the cloud top. In addition, the accuracy of the retrieved temperature profiles is greatly improved compared with the accuracies of the operational products. For the humidity retrievals, the mean RMSEs in the troposphere in winter and summer are both within 2 g kg^(–1). Moreover, the retrievals performed better compared with the ERA5 reanalysis data between 800 h Pa and 300 h Pa both in summer and winter in terms of RMSE. 展开更多
关键词 temperature and humidity profiles one-dimensional variational(1D-Var) GIIRS hyperspectral data
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Comparisons of the temperature and humidity profiles of reanalysis products with shipboard GPS sounding measurements obtained during the 2018 Eastern Indian Ocean Open Cruise 被引量:4
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作者 WANG Lei BAO Qing +4 位作者 LI Jinxiao WANG Dongxiao LIU Yimin WU Guoxiong WU Xiaofei 《Atmospheric and Oceanic Science Letters》 CSCD 2019年第3期177-183,共7页
It is important to be able to characterize the thermal conditions over the equatorial Indian Ocean for both weather forecasting and climate prediction. This study compared the equatorial eastern Indian Ocean (EEIO) te... It is important to be able to characterize the thermal conditions over the equatorial Indian Ocean for both weather forecasting and climate prediction. This study compared the equatorial eastern Indian Ocean (EEIO) temperature and relative humidity profiles from three reanalysis products (JRA-55, MERRA2, and FGOALS-f2) with shipboard global positioning system (GPS) sounding measurements obtained during the Eastern Indian Ocean Open Cruise in spring 2018. The FGOALS-f2 reanalysis product is based on the initialization module of a sub-seasonal to seasonal prediction system with a nudging-based data assimilation method. The results indicated that:(1) both JRA-55 and MERRA2 were reliable in characterizing the temperature profile from 850 to 600 hPa, with a maximum deviation of about <0.5℃. Both datasets showed a large negative deviation below 825 hPa, with a maximum bias of about 2℃ at 1000 hPa and 1.5℃ at 900 hPa, respectively.(2) JRA-55 showed good performance in characterizing the relative humidity profile above 850 hPa, with a maximum deviation of < 8%, while it showed much wetter conditions below 850 hPa. MERRA2 overestimated the relative humidity in the middle to lower troposphere, with a maximum deviation of about 15% at 925 hPa.(3) The FGOALS-f2 reanalysis product more accurately reproduced the temperature profile in the marine atmospheric boundary layer over the EEIO than that in JRA-55 and MERRA2, but showed much wetter conditions than the GPS sounding observations, with a maximum deviation of up to 20% at 600 hPa. Future applications of GPS sounding datasets are discussed. 展开更多
关键词 GPS sounding measurements equatorial eastern Indian Ocean temperature and humidity profiles reanalysis datasets characterization of performance
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Effect of relative humidity at either acute or chronic moderate temperature on growth performance and droppings' corticosterone metabolites of broilers 被引量:1
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作者 ZHOU ying LI Xiu-mei +1 位作者 ZHANG Min-hong FENG Jing-hai 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2019年第1期152-159,共8页
The present study aimed to investigate the effect of relative humidity(RH) at either acute or chronic moderate ambient temperature(Ta) on growth performance and droppings' corticosterone metabolites of broilers.Tw... The present study aimed to investigate the effect of relative humidity(RH) at either acute or chronic moderate ambient temperature(Ta) on growth performance and droppings' corticosterone metabolites of broilers.Two experiments were conducted: effect of RH(35,60 or 85%) on average daily feed intake(ADFI) and droppings' corticosterone metabolites at acute(1 d: 20–26 or 31–20°C,26 or 31°C for 6 h d–1 at 10:00–16:00) moderate Ta(experiment 1) and effect of RH(35,60 or 85%) on growth performance and droppings' corticosterone metabolites at chronic(step-wisely increasing temperature by 3°C every 3 d from 20 to 32°C within 15 d: 20–23–26–29–32°C) moderate Ta(experiment 2).Droppings were collected at the 2,4,6,8,and 22 h after Ta-RH controlled in experiment 1 and at the 2,4,6,and 22 h after Ta controlled to 32°C in experiment 2.The results showed that: 1) In experiment 1,85% RH increased(P<0.05) the droppings' corticosterone metabolites at the 2,6,8,and 22 h and 35% RH increased(P<0.05) it at the 2 and 22 h compared to the 60% RH.Moreover,85% RH further increased(P<0.05) it compared to the 35% RH,however,no difference(P>0.05) was found in ADFI among the three RH groups at acute moderate 26°C; 35 and 85% RH increased(P<0.05) droppings' corticosterone metabolites at the 2,6,8 and 22 h and decreased(P<0.05) ADFI compared to the 60% RH,moreover,85% RH further increased(P<0.05) droppings' corticosterone metabolites and further decreased(P<0.05) ADFI compared to the 35% RH at acute moderate 31°C; and the average of droppings' corticosterone metabolites in the whole period had a negative correlation(P<0.02) with the ADFI.2) In experiment 2,85% RH increased(P<0.01) droppings' corticosterone metabolites only at the 2 h and decreased(P<0.02) ADFI and average daily gain(ADG) compared to the 60% RH,no difference(P>0.05) in droppings' corticosterone metabolites was found between the 35 and 60% RH,however,35% RH decreased(P<0.01) ADG compared to the 60% RH,and the average of droppings' corticosterone metabolites in the whole period also had a negative correlation(P<0.02) with ADFI and ADG.In conclusion,droppings' corticosterone metabolites could be used as a RH stress index and low and high RH,especially high RH,reduced growth performance possibly through inducing RH stress at moderate temperature. 展开更多
关键词 broiler droppings’ CORTICOSTERONE METABOLITES relative humidity ACUTE MODERATE temperature CHRONIC MODERATE temperature
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