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Differences of Photosynthetic Characteristics of the Grape Cultivated in Greenhouse and Open Field in Turpan 被引量:3
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作者 马微 牛莹莹 +3 位作者 骆强伟 孙峰 伍国红 廖康 《Agricultural Science & Technology》 CAS 2016年第6期1285-1288,1340,共5页
[Objective] This study compared the leaf photosynthetic characteristics of Turpan grape cultivated in greenhouses and open field to provide a scientific basis for the high-quality and high-yield cultivation of grape. ... [Objective] This study compared the leaf photosynthetic characteristics of Turpan grape cultivated in greenhouses and open field to provide a scientific basis for the high-quality and high-yield cultivation of grape. [Method] Two precocious grape varieties as experimental materials were cultivated in greenhouses and open field, and their net photosynthetic rates (Pn), photo-response curves and CO2 response curves were determined using Li-400XT portable photosynthesis system. [Result] The leaf Pn of the two varieties cultivated in open field was higher than that in greenhouse. The Pn of Hongqitezao cultivated in open field was the highest, up to 19.79 μmol/(m^2·s); in the photo-response curves, Hongqitezao cultivated in greenhouse had the largest Pnmax and apparent quantum yield (AQY), while the Flame Seedless in greenhouse had the smallest light compensation point (LCP). The light saturation point (LSP) value of greenhouse cultivation was higher than that of open field cultivation. In the CO2 response test, the dark respiration rate (Rd) and Pnmax of greenhouse cultivation were higher than those of open field cultivation, and the carboxylation efficiency (CE) of greenhouse cultivation was lower than that of open field cultivation; the CO2 compensation point (CCP) and CO2 saturation point (CSP) of greenhouse cultivation were lower than those of open field cultivation. [Conclusion] The utilization of elevated light in greenhouse cultivation was more efficient than in open field cultivation; however, the utilization of elevated CO2 in greenhouse cultivation was weaker than tin open field cultivation. 展开更多
关键词 Greenhouse cultivation open field cultivation Photosynthetic characteristics Photo-response curve CO2 response curve
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Comparative Experiment of Ground Cucumber Varieties for Open Field Cultivation
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作者 Meiguang BI Yuanyuan CHE Lizhi YU 《Agricultural Biotechnology》 CAS 2018年第3期30-31,共2页
Seven ground cucumber varieties were cultivated in open field for the comparative experiment. The results showed that Texuan cucumber and Yantai ground cucumber had good commodity characters,good taste and high yield,... Seven ground cucumber varieties were cultivated in open field for the comparative experiment. The results showed that Texuan cucumber and Yantai ground cucumber had good commodity characters,good taste and high yield,and their output value exceeded 16 000 yuan/666. 7 m2,so they are more suitable for open cultivation in Yantai region. The next ones are Meiyu Diguawang and Aweishi ground cucumber. 展开更多
关键词 open field cultivation Ground cucumber VARIETY Comparative experiment
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Comparison of Cold Tolerance in Three Ground-cover Chrysanthemum Cultivars during Wintering in the Open Field
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作者 Xin ZHOU Man SHEN Pingsheng LENG 《Agricultural Biotechnology》 CAS 2022年第2期30-37,共8页
[Objectives]Among many chrysanthemum types,the ground-cover chrysanthemum cultivar group has the characteristics of dwarf plant,long flowering period,rich color and strong resistance to stress.This study aimed to scre... [Objectives]Among many chrysanthemum types,the ground-cover chrysanthemum cultivar group has the characteristics of dwarf plant,long flowering period,rich color and strong resistance to stress.This study aimed to screen out cultivars with strong cold tolerance in order that they can be used for planting in urban green space and economic forests in northern cold areas,so as to enrich the plant community structures of landscape in cold regions.[Methods]Three ground-cover chrysanthemum cultivars,i.e.,‘Meiaihuang’,‘Xinhong’and‘Zixunzhang’,were selected as the experimental materials.During the wintering period in the field in Beijing,they were observed and measured for the changes of the morphological manifestations and the physiological indices,and the relationship between the indices and low temperature was analyzed.The cold tolerance of the three ground-cover chrysanthemum cultivars was also comprehensively evaluated.[Results]During the open-field overwintering period,the root activity of the three ground-cover chrysanthemum cultivars increased slowly with cooling,decreased at the freezing low temperature,and then increased again in early spring.With natural cooling,the membrane injury percentages(MIPs)of the leaves and foot shoots increased significantly,and the contents of malondialdehyde(MDA)increased;the contents of soluble sugar(SS)and proline(Pro)gradually accumulated,and the contents of SS and Pro in foot shoots increased significantly in late winter;and the superoxide dismutase(SOD)activity showed a similar trend of rising slowly at first and then increasing significantly.There were correlations between MIPs in the leaves and foot shoots of the three cultivars and other physiological indices:a significant negative correlation with MDA content,and a significant positive correlation with SS content,Pro content and SOD activity.[Conclusions]Combining the morphological manifestations and physiological indices,the cold tolerance of the three ground-cover chrysanthemum cultivars was evaluated by the subordinate function method.The results showed that the cold tolerance of the three ground-cover chrysanthemum cultivars ranked as‘Meiaihuang’>‘Xinhong’>‘Zixunzhang’.The strong cold tolerance of foot shoots and roots was the main reason that the three ground-cover chrysanthemum cultivars could overwinter in the open field. 展开更多
关键词 Ground-cover chrysanthemum Cold tolerance Overwinter in the open field Comprehensive evaluation
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Analysis of the Declining of Open Field System in the Medieval England from the Perspective of Institutional Transition
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作者 Zhang Lin 《International English Education Research》 2015年第9期46-48,共3页
Open field system is the most important land farming system in the middle part of the Medieval England. It has the property of private property and common property right and exited for very long time. This article ana... Open field system is the most important land farming system in the middle part of the Medieval England. It has the property of private property and common property right and exited for very long time. This article analyzed how the open field system was replaced by the enclosure system from the perspective of institutional t transition. By carrying on the detailed investigation, it can provide certain enlightenments and references to deepen rural reform, especially promoting the reasonable transfer of rural land use rights in China. 展开更多
关键词 open field System Induced Institutional Transition Imposed Institutional Transition
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宁心解郁胶囊对慢性应激抑郁模型大鼠Open-Field行为的影响 被引量:2
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作者 孙亚男 邹忆怀 朱陵群 《天津中医药》 CAS 2014年第1期42-46,共5页
[目的]探讨宁心解郁胶囊的抗抑郁作用及可能的机制。[方法]以孤养加慢性轻度不可预见性应激方法建立大鼠抑郁模型,用Open-Field方法进行行为学评定,观察模型大鼠给药前后的行为学变化。[结果]经过孤养加慢性轻度不可预见性应激方法造模... [目的]探讨宁心解郁胶囊的抗抑郁作用及可能的机制。[方法]以孤养加慢性轻度不可预见性应激方法建立大鼠抑郁模型,用Open-Field方法进行行为学评定,观察模型大鼠给药前后的行为学变化。[结果]经过孤养加慢性轻度不可预见性应激方法造模后的大鼠,Open-Field行为学评定中模型组大鼠的总路程、平均速度、中央活动路程、中央活动时间、各角的活动路程和时间均较空白组有统计学差异(P<0.05)。治疗后大鼠的总活动路程、平均速度、中央活动时间、中央活动路程、下边活动路程、下边活动时间、各角的活动路程和时间均较模型组有统计学差异(P<0.05),活动路程较模型组增加,活动时间较模型组增加,且以中剂量组效果显著。[结论]宁心解郁胶囊具有抗抑郁作用,对大鼠抑郁行为有明显改善。 展开更多
关键词 宁心解郁胶囊 慢性应激抑郁模型 openfield实验 行为学
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Life cycle assessment of open field and greenhouse cultivation of lettuce and barley 被引量:7
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作者 Georgios Bartzas Dimitra Zaharaki Kostas Komnitsas 《Information Processing in Agriculture》 EI 2015年第3期191-207,共17页
In the present paper,a life cycle assessment(LCA)study regarding barley and lettuce production in Spain(Barrax and Santomera regions)and Italy(Albenga region)in both open field(OF)and standard greenhouse(GH)cultivatio... In the present paper,a life cycle assessment(LCA)study regarding barley and lettuce production in Spain(Barrax and Santomera regions)and Italy(Albenga region)in both open field(OF)and standard greenhouse(GH)cultivations was performed in order to evaluate energy consumption and environmental impacts.The study examines also the impact of the use of compost produced from agricultural wastes(AW).In this context,a detailed life cycle directory was created,based on site-specific experimental data,and used for a holistic cradle-to-gate LCA analysis using the GaBi 6 software package and specific related databases.In order to reveal the importance of system boundaries,factors that are often excluded from LCA studies,such as agricultural machinery manufacture,nursery production,waste management and raw materials transportation have been considered.According to the results of this study,the use of compost for fertilization of both crops is considered a good agronomic and ecological strategy in order to maintain productivity in terms of yield,especially in the case of greenhouse cultivation,and improve overall sustainability in the agricultural sector.Moreover,the phases of compost production,irrigation system,and greenhouse construction and operation were identified as the three main‘‘hotspots”with the highest environmental impact and energy contribution in all studied cases.Finally,improvements to reduce those impacts were proposed. 展开更多
关键词 LCA Agricultural waste LETTUCE BARLEY open field GREENHOUSE
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Suitability of open-field autorefractors as pupillometers and instrument design effects
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作者 Carles Otero Mikel Aldaba +3 位作者 Oriol Ferrer Andrea Gascón Juan C Ondategui-Parra Jaume Pujol 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2017年第4期567-572,共6页
AIM:To determine the agreement and repeatability of the pupil measurement obtained with VIP-200(Neuroptics),Power Ref II(Plusoptix),WAM-5500(Grand Seiko) and study the effects of instrument design on pupillomet... AIM:To determine the agreement and repeatability of the pupil measurement obtained with VIP-200(Neuroptics),Power Ref II(Plusoptix),WAM-5500(Grand Seiko) and study the effects of instrument design on pupillometry.METHODS:Forty patients were measured twice in low,mid and high mesopic.Repeatability was analyzed with the within-subject standard deviation(Sw) and paired t-tests.Agreement was studied with Bland-Altman plots and repeated measures ANOVA.Instrument design analysis consisted on measuring pupil size with Power Ref II simulating monocular and binocular conditions as well as with proximity cues and without proximity cues.RESULTS:The mean difference(±standard deviation) between test-retest for low,mid and high mesopic conditions were,respectively:-0.09(±0.16),-0.05(±0.18) and-0.08(±0.23) mm for Neuroptics,-0.05(±0.17),-0.12(±0.23) and-0.17(±0.34) mm for WAM-5500,-0.04(±0.27),-0.13(±0.37) and-0.11(±0.28) mm for Power Ref II.Regarding agreement with Neuroptics,the mean difference for low,mid and high mesopic conditions were,respectively:-0.48(±0.35),-0.83(±0.52) and-0.38(±0.56) mm for WAM-5500,-0.28(±0.56),-0.70(±0.55) and-0.61(±0.54) mm for Power Ref II.The mean difference of binocular minus monocular pupil measurements was:-0.83(±0.87) mm;and with proximity cues minus without proximity cues was:-0.30(±0.77) mm.CONCLUSION:All the instruments show similar repeatability.In all illumination conditions,agreement of Neuroptics with WAM-5500 and Power Ref II is not good enough,which can be partially induced due to their open field design. 展开更多
关键词 PUPIL REPEATABILITY AGREEMENT open-field
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Positions Open in the Field of Plasma and Fusion
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第5期i001-i001,共1页
Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is sear... Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering. 展开更多
关键词 Positions open in the field of Plasma and Fusion open
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Positions Open in the Field of Plasma and Fusion
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第3期i001-i001,共1页
Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important Laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is sear... Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important Laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering. 展开更多
关键词 open Positions open in the field of Plasma and Fusion
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Positions Open in the Field of Plasma and Fusion
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《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第6期i004-i004,共1页
Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is sear... Institute of Plasma Physics, Chinese Academy of Sciences (ASIPP), one of the most important laboratories on magnetically confined fusion in China and the Nuclear Fusion Research Center of the World Laboratory, is searching for 5 senior and 10 junior scientists of plasma and fusion in the following superconducting tokamak research areas: theory and simulation, diverter and edge physics, plasma diagnostics, electron cyclotron resonant heating, ion cyclotron resonant heating, lower hybrid wave, neutral beam injection, reactor design, fusion material, superconducting engineering. 展开更多
关键词 open Positions open in the field of Plasma and Fusion
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Experimental Measurement of Minority Carriers Effective Lifetime in Silicon Solar Cell Using Open Circuit Voltage Decay under Magnetic Field in Transient Mode
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作者 Alain Diasso Raguilignaba Sam +1 位作者 Bernard Zouma François Zougmoré 《Smart Grid and Renewable Energy》 2020年第11期181-190,共10页
<span style="font-family:Verdana;">This manuscript presents a simple method for excess minority carriers’ lifetime measurement</span><span style="font-family:""> </span&g... <span style="font-family:Verdana;">This manuscript presents a simple method for excess minority carriers’ lifetime measurement</span><span style="font-family:""> </span><span style="font-family:""><span style="font-family:Verdana;">within the base region of p-n junction polycrystalline solar </span><span style="font-family:Verdana;">cell</span></span><span style="font-family:""> </span><span style="font-family:Verdana;">in transient mode.</span><span style="font-family:""> </span><span style="font-family:Verdana;">This work is an experimental transient</span><span style="font-family:Verdana;"> 3-Dimensionnal study.</span><span style="font-family:""> </span><span style="font-family:Verdana;">The magnitude of the magnetic field B is varied from 0 mT to 0.045 mT. Indeed, the solar cell is illuminated by a stroboscopic flash with air mass 1.5</span><span style="font-family:""> </span><span style="font-family:Verdana;">and under magnetic field in transient state.</span><span style="font-family:""> </span><span style="font-family:Verdana;">The experimental details are assumed in a figure. The procedure is outlined by the Open Circuit Voltage Decay analysis. Effective minority carrier life-time is calculated by fitting the linear zone of the transient voltage decay curve</span><span style="font-family:""> </span><span style="font-family:Verdana;">because linear decay is an ideal decay. The kaleidagraph software permits access to the slope of the curve which is inversely proportional to the</span><span style="font-family:""> </span><span style="font-family:Verdana;">lifetime. The external magnetic effects</span><span style="font-family:""> </span><span style="font-family:Verdana;">on minority carriers’ effective lifetime </span><span style="font-family:Verdana;">is</span><span style="font-family:Verdana;"> then</span><span style="font-family:""> </span><span style="font-family:Verdana;">presented and analyzed.</span><span style="font-family:""> </span><span style="font-family:Verdana;">The analysis show</span><span style="font-family:Verdana;">s</span><span style="font-family:Verdana;"> that the charge carrier</span><span style="font-family:Verdana;">’</span><span style="font-family:Verdana;">s effective lifetime decrease with the magnetic field increase.</span> 展开更多
关键词 Carrier Lifetime FITTING Magnetic field open Circuit Voltage Decay
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Bruch's membrane opening-minimum rim width and visual field loss in glaucoma:a broken stick analysis 被引量:1
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作者 Keun-Heung Park Ji-Woong Lee +2 位作者 Jin-Mi Kim Kouros Nouri-Mahdavi Joseph Caprioli 《International Journal of Ophthalmology(English edition)》 SCIE CAS 2018年第5期828-834,共7页
AIM:To determine the Bruch's membrane opening-minimum rim width(BMO-MRW) tipping point where corresponding visual field(VF) damages become detectable.METHODS:A total of 85 normal subjects and 83 glaucoma patie... AIM:To determine the Bruch's membrane opening-minimum rim width(BMO-MRW) tipping point where corresponding visual field(VF) damages become detectable.METHODS:A total of 85 normal subjects and 83 glaucoma patients(one eye per participant) were recruited for the study.All of the patients had VF examinations and spectral-domain optical coherence tomography to measure the BMO-MRW.Total deviation values for 52 VF points were allocated to the corresponding sector according to the Garway-Heath distribution map.To evaluate the relationship between VF loss and BMOMRW measurements,a "broken-stick" statistical model was used.The tipping point where the VF values started to sharply decrease as a function of BMO-MRW measurements was estimated and the slopes above and below this tipping point were compared.RESULTS:A 25.9% global BMO-MRW loss from normative value was required for the VF loss to be detectable.Sectorally,substantial BMO-MRW thinning in inferotemporal sector(33.1%) and relatively less BMO-MRW thinning in the superotemporal sector(8.9%) were necessary for the detection of the VF loss.Beyond the tipping point,the slopes were close to zero throughout all of the sectors and the VF loss was unrelated to the BMO-MRW loss.The VF loss was related to the BMO-MRW loss below the tipping point.The difference between the two slopes was statistically significant(P≤0.002).CONCLUSION:Substantial BMO-MRW loss appears to be necessary for VF loss to be detectable in patients with open angle glaucoma with standard achromatic perimetry. 展开更多
关键词 Bruch's membrane opening-minimum rim width visual field loss structure function relationship broken stick model optical coherence tomography
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基于Open Inventor的油藏饱和度场可视化技术研究 被引量:1
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作者 聂永丹 李福庆 张岩 《微型电脑应用》 2014年第7期17-18,21,共3页
油藏数值模拟过程中饱和度场与等值线反映了油藏体物理参数的变化趋势,对石油勘探开发行业分析含油饱和度与剩余油分布具有重要意义。采用Open Inventor可视化开发包研究含油饱和度场的绘制技术,利用VC++实现了油藏饱和度场动态绘制,提... 油藏数值模拟过程中饱和度场与等值线反映了油藏体物理参数的变化趋势,对石油勘探开发行业分析含油饱和度与剩余油分布具有重要意义。采用Open Inventor可视化开发包研究含油饱和度场的绘制技术,利用VC++实现了油藏饱和度场动态绘制,提供了饱和度场和等值线的直观展示方式。 展开更多
关键词 open INVENTOR 油藏体 饱和度场 等值线
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Large-scale evaluation of pea(Pisum sativum L.)germplasm for cold tolerance in the field during winter in Qingdao 被引量:3
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作者 Xiaoyan Zhang Shuwei Wan +3 位作者 Junjie Hao Jinguo Hu Tao Yang Xuxiao Zong 《The Crop Journal》 SCIE CAS CSCD 2016年第5期377-383,共7页
As a cool-season crop, pea(Pisum sativum L.) can tolerate frost at the vegetative stage but experiences yield loss when freezing stress occurs at the reproductive stage. Cold-tolerance improvement of pea varieties is ... As a cool-season crop, pea(Pisum sativum L.) can tolerate frost at the vegetative stage but experiences yield loss when freezing stress occurs at the reproductive stage. Cold-tolerance improvement of pea varieties is important for stable yield and expansion of the winter pea planting area. Under natural low-temperature conditions during winter in Qingdao,Shandong, China, we evaluated the cold tolerance of 3672 pea germplasm accessions in the field and categorized them as displaying high resistance(214), moderate resistance(835), or susceptibility(2623). The highly and moderately resistant genotypes were validated in the following year. We found that genotypes from the winter production region showed higher cold tolerance than genotypes from the spring production region. The accessions identified as having high levels of cold tolerance are recommended as potential genetic resources in cold-tolerance breeding of pea. 展开更多
关键词 Pisum sativum L. Cold tolerance Germplasm evaluation open-field experiment
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Study on transient aerodynamic characteristics of parachute opening process 被引量:20
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作者 Li Yu Xiao Ming 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2007年第6期627-633,共7页
In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficu... In the research of parachute, canopy inflation process modeling is one of the most complicated tasks. As canopy often experiences the largest deformations and loa-dings during a very short time, it is of great difficulty for theoretical analysis and experimental measurements. In this paper, aerodynamic equations and structural dynamics equations were developed for describing parachute opening process, and an iterative coupling solving strategy incorpo- rating the above equations was proposed for a small-scale, flexible and flat-circular parachute. Then, analyses were carried out for canopy geometry, time-dependent pressure difference between the inside and outside of the canopy, transient vortex around the canopy and the flow field in the radial plane as a sequence in opening process. The mechanism of the canopy shape development was explained from perspective of transient flow fields during the inflation process. Experiments of the parachute opening process were conducted in a wind tunnel, in which instantaneous shape of the canopy was measured by high velocity camera and the opening loading was measured by dynamometer balance. The theoretical predictions were found in good agreement with the experimental results, validating the proposed approach. This numerical method can improve the situation of strong dependence of parachute research on wind tunnel tests, and is of significance to the understanding of the mechanics of parachute inflation process. 展开更多
关键词 PARACHUTE opening process Numerical simulation Flow field characteristics AERODYNAMICS Structural dynamics
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基于OpenFOAM的弧板式透空堤水动力特性数值研究 被引量:1
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作者 李钦 李雪艳 +4 位作者 王庆 张俊斌 王丽雪 张之晨 伊锋 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2020年第3期412-419,共8页
为探讨一种弧板式透空堤的水动力特性,基于OpenFOAM建立了波浪与弧板式透空堤相互作用数值模型,探讨了弧板式透空堤的消浪特性、压强特性及流场分布情况.结果表明:本次数值试验范围内,波浪对弧板式透空堤的透射系数随相对板宽的增大而减... 为探讨一种弧板式透空堤的水动力特性,基于OpenFOAM建立了波浪与弧板式透空堤相互作用数值模型,探讨了弧板式透空堤的消浪特性、压强特性及流场分布情况.结果表明:本次数值试验范围内,波浪对弧板式透空堤的透射系数随相对板宽的增大而减小,反射系数则相反.弧板式透空堤上下表面所受波浪正压强与负压强分布呈现对称特性,且大部分工况下的波浪压强极值发生在结构物偏迎浪向一侧的测点位置处.弧板式透空堤位于静水面及以上时,消浪效果明显优于其位于静水面以下.弧板式透空堤对其周围流场影响显著,在其迎浪向与背浪向位置均产生较为明显的漩涡. 展开更多
关键词 弧板式透空堤 消浪特性 波浪压强 流场 openFOAM
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基于OpenCL的Gzip数据压缩算法 被引量:8
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作者 赵雅倩 李龙 +4 位作者 郭跃超 史宏志 郭振华 魏士欣 陈继承 《计算机应用》 CSCD 北大核心 2018年第A01期112-115,130,共5页
目前,数据压缩算法主要基于串行编程模型设计和实现,导致数据压缩速率较低,因而无法满足大数据分析和处理等应用的实时性需求。为了解决这个问题,以常用数据压缩算法Gzip为蓝本,提出一种实现无损数据压缩算法的专用硬件电路。首先,采用... 目前,数据压缩算法主要基于串行编程模型设计和实现,导致数据压缩速率较低,因而无法满足大数据分析和处理等应用的实时性需求。为了解决这个问题,以常用数据压缩算法Gzip为蓝本,提出一种实现无损数据压缩算法的专用硬件电路。首先,采用多字典并行查找的设计方案提高重复数据的查找速率;接着,采用匹配长度拼接技术提升数据的压缩效果;最后,采用开放计算语言(Open CL)实现了所提出的专用硬件电路。基于现场可编程门阵列(FPGA)进行功能验证和性能评测,结果表明:与基于串行编程模型设计和实现的数据压缩算法相比,所提出的硬件电路在取得适当压缩率的同时,显著地提高了数据的压缩速率,压缩速率可达12 Gb/s。 展开更多
关键词 数据压缩 开放计算语言 Gzip算法 现场可编程门阵列 硬件加速
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基于Open FOAM的液压阀流场数值模拟及分析 被引量:2
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作者 张志鹏 古镇铨 +2 位作者 袁聪 罗宽 庄剑威 《液压气动与密封》 2022年第7期58-62,共5页
由于目前液压阀的流场结构随开口度的变化趋势尚未得到透彻的研究,针对液压阀在相同压差条件下的流场结构随开口度的变化,利用OpenFOAM开源平台对液压阀的不同阀门开口度开展了数值模拟,分析速度场、漩涡结构以及压力分布,揭示了液压阀... 由于目前液压阀的流场结构随开口度的变化趋势尚未得到透彻的研究,针对液压阀在相同压差条件下的流场结构随开口度的变化,利用OpenFOAM开源平台对液压阀的不同阀门开口度开展了数值模拟,分析速度场、漩涡结构以及压力分布,揭示了液压阀的流场结构随开口度的变化情况。结果表明:流场流动与阀门的开口度密切相关。流动的不稳定性伴随着开口度的增大而增大,流动的不稳定性的产生和漩涡相关,且流动具有强烈的时间依赖特性。五种开口度的压力最低的区域均为射流自由剪切层并非在阀体阀门端点处,且负压峰值出现在下游处的自由剪切层,与漩涡的初生位置较为吻合。这将为液压阀的优化设计提供理论基础。 展开更多
关键词 液压阀 开口度 数值模拟 流场结构
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Temporal interference driven by an oscillating electric field in photodetachment of H^- ion
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作者 王德华 李梦芝 +1 位作者 宋鸿娜 任笑笑 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第2期314-320,共7页
The real time domain interferometry for the photodetachment dynamics driven by the oscillating electric field has been studied for the first time. Both the geometry of the detached electron trajectories and the electr... The real time domain interferometry for the photodetachment dynamics driven by the oscillating electric field has been studied for the first time. Both the geometry of the detached electron trajectories and the electron probability density are shown to be different from those in the photodetachment dynamics in a static electric field. The influence of the oscillating electric field on the detached electron leads to a surprisingly intricate shape of the electron waves, and multiple interfering trajectories generate complex interference patterns in the electron probability density. Using the semiclassical open-orbit theory, we calculate the interference patterns in the time-dependent electron probability density for different electric field strengths, different frequencies and phases in the oscillating electric field. This method is universal, and can be extended to study the photoionization dynamics of the atoms in the time-dependent electric field. Our study can guide the future experimental researches in the photodetachment or photoionization microscopy of negative ions and atoms in the oscillating electric field. 展开更多
关键词 temporal interference photodetachment dynamics oscillating electric field semiclassical open-orbit theory
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半夏泻心汤对功能性消化不良大鼠抑郁状态及促肾上腺皮质激素释放因子相关通路的影响
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作者 耿琦 李敬伟 +1 位作者 凌江红 蒋健 《陕西中医》 CAS 2024年第2期147-152,共6页
目的:观察半夏泻心汤对功能性消化不良(FD)大鼠抑郁样行为、下丘脑促肾上腺皮质激素释放因子(CRF)及其受体CRF-R1、CRF-R2的影响。方法:48只SPF级Wistar大鼠随机分为空白组、模型组、氟西汀组、半夏泻心汤低、中、高剂量组,共六组,每组... 目的:观察半夏泻心汤对功能性消化不良(FD)大鼠抑郁样行为、下丘脑促肾上腺皮质激素释放因子(CRF)及其受体CRF-R1、CRF-R2的影响。方法:48只SPF级Wistar大鼠随机分为空白组、模型组、氟西汀组、半夏泻心汤低、中、高剂量组,共六组,每组各8只。空白组正常饲养,其余五组采用不规则喂养+夹尾激惹刺激法造模,造模成功后半夏泻心汤低、中、高各剂量组分别给予0.62、1.24、2.48 g/ml剂量灌胃,氟西汀组给予2 mg/kg氟西汀,空白组及模型组均给予同等容积的蒸馏水,各组连续灌胃14 d。干预结束后采用糖水偏好实验和旷场实验测试各组抑郁样行为;HE染色观察大鼠胃窦组织基本形态;RT-qPCR和Western blot检测大鼠下丘脑中CRF、CRF-R1和CRF-R2 mRNA和蛋白的表达。结果:与空白组比较,模型组大鼠体重、糖水偏好度、旷场实验移动总距离和直立次数均明显下降(P<0.05);下丘脑中CRF、CRF-R1 mRNA和蛋白表达均明显升高(P<0.01),CRF-R2 mRNA和蛋白的表达均明显降低(P<0.01)。与模型组比较,半夏泻心汤各剂量组大鼠的体重、糖水偏好度、旷场实验移动总距离和直立次数均明显增加(P<0.05);半夏泻心汤各剂量组FD大鼠下丘脑中CRF、CRF-R1 mRNA的表达量均明显降低(P<0.01),CRF-R2 mRNA的表达明显升高;半夏泻心汤高剂量组FD大鼠下丘脑中CRF蛋白表达均明显降低(P<0.01),半夏泻心汤各剂量组FD大鼠下丘脑中CRF-R1蛋白表达明显降低(P<0.01),CRF-R2蛋白表达升高(P<0.05)。结论:半夏泻心汤可通过调控CRF通路,恢复CRF-R1和CRF-R2的平衡状态,发挥抗抑郁的作用。 展开更多
关键词 功能性消化不良 半夏泻心汤 抑郁状态 糖水偏好实验 旷场实验 促肾上腺皮质激素释放因子通路
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