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苏符苏籀节行分化考辨——兼论苏籀绍兴和议期间的创作心态
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作者 李法然 《理论界》 2018年第4期80-88,共9页
苏符绍兴间两次不附秦桧,其中固然有个人节行,但背后更有赵鼎与秦桧两大政治势力的角力,苏符虽非赵鼎系官员,却因种种原因参与到这场角力之中。苏籀和金言论出于时事影响下自身的思维逻辑以及对宋金关系的判断,而非阿附秦桧,其谢秦桧启... 苏符绍兴间两次不附秦桧,其中固然有个人节行,但背后更有赵鼎与秦桧两大政治势力的角力,苏符虽非赵鼎系官员,却因种种原因参与到这场角力之中。苏籀和金言论出于时事影响下自身的思维逻辑以及对宋金关系的判断,而非阿附秦桧,其谢秦桧启不过是转官之后的例行公事,两次转官皆事出有因,并不由于秦桧的提携。二人所谓的节行分化,实际上可以在更为广阔的历史视野中作出合理的解释,从而在一定程度上洗脱苏籀"文丐奔竞"的恶名。苏籀绍兴和议期间的创作心态,以绍兴十五年为界,此前急于仕进,此后则疏离政治。影响这一转变的因素则是秦桧权力的扩大及其对包括元祐后学在内的政治对手的打压。 展开更多
关键词 苏符 苏籀 节行 绍兴和议 创作心态
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《李娃传》不是“爱情主题”小说
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作者 杜贵晨 《南都学坛(南阳师范学院人文社会科学学报)》 2018年第3期38-43,共6页
《李娃传》所写,是一个古代"草根"女子逆袭为郡国夫人的旷世典型。历来中国文学史教材论《李娃传》,多认为是"以爱情为主题"或"全力表现人世间的男女之情"的小说,可概括为"爱情主题"说。但这... 《李娃传》所写,是一个古代"草根"女子逆袭为郡国夫人的旷世典型。历来中国文学史教材论《李娃传》,多认为是"以爱情为主题"或"全力表现人世间的男女之情"的小说,可概括为"爱情主题"说。但这既非《李娃传》作者的创作意图,也不合于文本描写的实际。《李娃传》的主题不是"爱情",而是"节行"。《李娃传》的"节行"主题有与"爱情"不相逊色的传统文化意义。 展开更多
关键词 《李娃传》 “爱情主题” “证实偏见” 节行
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论“三言”中的商人形象
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作者 程传荣 《安顺学院学报》 2002年第2期10-13,共4页
冯梦龙“三言”中的商人形象的塑造,跟他的小说中的其他形象一样,都是出自于道德教化的目的,这些商人形象分为正反两种类型,作者借助这两类人物,宣扬了他的节行孝义的道德观念。这些商人形象对今天的读者来说,仍有一定的认识价值。
关键词 商人题材 道德教化 节行孝义
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Leaf Volatiles from Host Tree Acer negundo : Diurnal Rhythm and Behavior Responses of Anoplophora glabripennis to Volatiles in Field 被引量:8
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作者 李建光 金幼菊 +2 位作者 骆有庆 许志春 陈华君 《Acta Botanica Sinica》 CSCD 2003年第2期177-182,共6页
The volatile compounds from ash-leaf maple (Acer negundo L.) were examined by adsorption-thermodesorption and GC-MS. Thirty-two compounds, including alcohols, ketones, aldehydes, esters, terpenoids, carboxylic acids, ... The volatile compounds from ash-leaf maple (Acer negundo L.) were examined by adsorption-thermodesorption and GC-MS. Thirty-two compounds, including alcohols, ketones, aldehydes, esters, terpenoids, carboxylic acids, etc. were identified. The analysis revealed that the diurnal rhythm of release of volatile compounds from maple differed in July and in August. In July, the releasing of most volatile compounds reached the peak at 14 o'clock, when in August, the emission of volatile compounds reached the peak at 10 o'clock. Besides diurnal rhythm, there also existed other differences in the releasing of volatiles and their relative contents in July and in August. A possible explanation for this phenomenon is the maturation of leaves, since the sampling conditions were the same both in July and August. At the same time, the response of Anoplophora glabrpennis Motschulsky to volatiles was examined with field bioassay with traps. cis-3-hexen-1-ol was found to be more effective to attract A. glabrpennis than other volatiles released by ash-leaf maple tree in field trapping test. A mixture of 1-butanol, 1-pentanol and 2-pentanol was tested to be the most attractive to A. glabripennis among all tested volatiles. More field trapping tests should be conducted. 展开更多
关键词 Acer negundo Anoplophora glabtipennis VOLATILE diurnal rhythm behavioral response
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Seasonal variation and synchronization of sexual behaviors in free-ranging male Tibetan macaques (Macaca thibetana) at Huangshan, China 被引量:3
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作者 夏东坡 李进华 +3 位作者 朱勇 孙丙华 Lori K SHEERAN Megan D MATHESON 《Zoological Research》 CAS CSCD 北大核心 2010年第5期509-515,共7页
Although seasonal breeding has been documented in many non-human primates, it is not clear whether sexual behaviors show seasonal variation among male individuals. To test this hypothesis, the focal animal sampling me... Although seasonal breeding has been documented in many non-human primates, it is not clear whether sexual behaviors show seasonal variation among male individuals. To test this hypothesis, the focal animal sampling method and continuous recording were used to investigate seasonal variation and synchronization of sexual behaviors in five male Tibetan macaques (Macaca thibetana) at Mt. Huangshan from Oct 2005 to Sept 2006. Both copulatory and sexually motivated behaviors (i.e., sexual chase, grimace, and sexual-inspection), which were significantly higher in the mating season than non-mating season. Furthermore, seasonal variations of sexual behaviors, including copulatory and sexually motivated behaviors, were synchronized among males. The results shed light on sexual competition and tactics for reproductive success of male M. thibetana and other non-human primates with seasonal breeding. 展开更多
关键词 Tibetan macaques (Macaca thibetana) Males Sexual behavior Seasonal variation Synchrony
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Status and behavior of the Black-necked Crane (Grus nigricollis) in the Altun Mountain Reserve,Xinjiang
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作者 张同 马鸣 +2 位作者 丁鹏 徐峰 Paul J.BUZZARD 《Chinese Birds》 2012年第3期199-205,共7页
The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,popula... The Black-necked Crane (Grus nigricollis) is an endemic species of the Qinghai-Tibetan Plateau,with its population in Xinjiang largely found in the Kunlun and Altun mountain regions.A survey of the distribution,population dynamics,flock size and behavior was conducted in Altun Mountain National Natural Reserve from September to November 2011.We investigated the size and distribution of its population in this area with a sample spot survey and by direct counting.We found Black-necked Cranes on the wetlands of Wuzunxiaoer,Yusup Aleksei,Yaziquan,Qimantag,Tula Ranch and elsewhere,where we recorded 126 individual birds of the species in Yixiekepati (37° 15′-37°23′N,90°11′-90°20′E,elevation 3903 m),the largest population we have observed in this area.In the reserve,the population consists of about 180-200 birds.Combined with previous records,we conclude that more than 260 Black-necked Cranes live in Xinjiang.Cranes gathered conspicuously in the middle of October where the highest number of birds appeared on 29 October.All of the cranes had migrated out of this area by 6 November.Time budgets and diurnal behavior rhythms of Blacknecked Cranes were observed in the Yixiekepati wetland at daylight (from 06:00 to 18:00).Foraging was the most prevalent type of behavior during the autumn period,accounting for 58.9% of the diurnal time budget,followed by preening (13.2%),vigilance (9.5%),walking (8.2%),flying (3.5%),resting (3.4%),chirping (2.7%) and other types of behavior (0.6%). 展开更多
关键词 Black-necked Crane Grus nigricollis distribution population size behavior rhythm XINJIANG
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A SEASONAL INFLUENZA THEORY AND MATHEMATICAL MODEL INCORPORATING METEOROLOGICAL AND SOCIO-BEHAVIORAL FACTORS 被引量:1
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作者 周智翔 《Journal of Tropical Meteorology》 SCIE 2009年第1期1-12,共12页
On the basis of a comprehensive literature review and data analysis of global influenza surveillance, a transmission theory based numerical model is developed to understand the causative factors of influenza seasonali... On the basis of a comprehensive literature review and data analysis of global influenza surveillance, a transmission theory based numerical model is developed to understand the causative factors of influenza seasonality and the biodynamical mechanisms of seasonal flu. The model is applied to simulate the seasonality and weekly activity of influenza in different areas across all continents and climate zones around the world. Model solution and the good matches between model output and actual influenza indexes affirm that influenza activity is highly auto-correlative and relies on determinants of a broad spectrum. Internal dynamic resonance; variations of meteorological elements (solar radiation, precipitation and dewpoint); socio-behavioral influences and herd immunity to circulating strains prove to be the critical explanatory factors of the seasonality and weekly activity of influenza. In all climate regions, influenza activity is proportional to the exponential of the number of days with precipitation and to the negative exponential of quarter power of sunny hours. Influenza activity is a negative exponential function of dewpoint in temperate and arctic regions and an exponential function of the absolute deviation of dewpoint from its annual mean in the tropics. Epidemics of seasonal influenza could be deemed as the consequence of the dynamic resonance and interactions of determinants. Early interventions (such as opportune vaccination, prompt social distancing, and maintaining incidence well below a baseline) are key to the control and prevention of seasonal influenza. Moderate amount of sunlight exposure or Vitamin D supplementation during rainy and short-day photoperiod seasons, more outdoor activities, and appropriate indoor dewpoint deserve great attention in influenza prevention. To a considerable degree, the study reveals the mechanism of influenza seasonality, demonstrating a potential for influenza activity projection. The concept and algorithm can be explored for further applications. 展开更多
关键词 influenza influenza seasonality influenza modeling solar radiation temperature precipitation weather vitamin D
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Degradation of joint surface morphology, shear behavior and closure characteristics during cyclic loading 被引量:5
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作者 FAN Wen-chen CAO Ping LONG Long 《Journal of Central South University》 SCIE EI CAS CSCD 2018年第3期653-661,共9页
In order to investigate the failure mechanism of rock joint,a series of laboratory tests including cyclic direct shear tests under constant normal load(CNL)conditions were conducted.Morphology parameters of the rock j... In order to investigate the failure mechanism of rock joint,a series of laboratory tests including cyclic direct shear tests under constant normal load(CNL)conditions were conducted.Morphology parameters of the rock joint surface were precisely calculated by means of a three-dimensional laser scanning machine.All test results were analyzed to investigate the shear behavior and normal displacement behavior of rock joints under CNL conditions.Degradation of rock joint surface during cyclic shear tests was also analyzed.The comparison results of the height parameters and the hybrid parameters of the joint surface during cyclic tests show that the degradation of the surface mostly happens in the first shear and the constant normal loads imposed on the joints have significant promotion effects on the morphology degradation.During cyclic shear tests,joints surfaces evolve from rough state to smooth state but keep an overall undulation.Dilatancy of rock joints degrades with the degradation of joint surface and the increase of normal loads.The closure deformation of joint is larger than that of the intact rock,and the normal stiffness increases with the increase of shearing times. 展开更多
关键词 rock joint constant normal load condition surface morphology degradation shear behavior joint closure characteristic
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Fine particle aggregating and flotation behavior induced by high intensity conditioning of a CO_2 saturation slurry 被引量:5
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作者 SUN Wei DENG Mei-jiao HU Yue-hua 《Mining Science and Technology》 EI CAS 2009年第4期483-488,共6页
The influence on fine particle aggregation and flotation behavior induced by high intensity conditioning(HIC) from saturated of the slurry with CO2 saturation was investigated.Bubble size measurements were conducted.T... The influence on fine particle aggregation and flotation behavior induced by high intensity conditioning(HIC) from saturated of the slurry with CO2 saturation was investigated.Bubble size measurements were conducted.The effect of dissolved gas,xanthate addition and agitation speed on fine sphalerite particle aggregation-and flotation-behavior were studied.The results show that during HIC in air or CO2 saturated water xanthate acts as a frother.The dissolved gas content in the pulp and HIC play a synergistic role in promoting fine particle aggregation and hence flotation;a significantly enhanced aggregation of fine sphalerite particles in a CO2 saturated slurry by HIC is observed.The aggregate size increased when the agitation speed was increased from 700 r/min to 1500 r/min.Increasing the HIC speed to 1500 r/min caused a positive impact on flotation kinetics.Further increasing the speed to 2000 r/min resulted in an adverse effect on flotation kinetics. 展开更多
关键词 CO2 saturation high intensive conditioning CAVITATION aggregation FLOTATION
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Influencing factors analysis of spontaneous knee joint osteoarthritis among middle aged and old aged pople in Xi'an 被引量:4
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作者 王伟 王坤正 +4 位作者 党晓谦 柏传毅 王春生 时志斌 马树强 《Journal of Medical Colleges of PLA(China)》 CAS 2007年第3期179-184,共6页
Objective:To explore the prevalence rate of knee joint osteoarthritis and its pathogenetic fea- tures among the middle-aged and old aged people in the urban and rural area of Xi'an.Methods:From May to October 2005... Objective:To explore the prevalence rate of knee joint osteoarthritis and its pathogenetic fea- tures among the middle-aged and old aged people in the urban and rural area of Xi'an.Methods:From May to October 2005,1538 Han nationality above 40 years in Xi'an were investigated according to strati- fied and cluster random sampling.The same questionnaire was delivered to subjects who had been given normotopia and lateral position radiographic examination in both knees.Excluded from etiological arthri- tis,some subjects with clinical symptoms and a radiographic grade (beyond Kellgren & Lawrence gradeⅡ) were finally diagnosed as spontaneous knee joint osteoarthritis.All analyses were performed with SPSS 13.0 and t test,U test.Single factor analysis and multiple logistic regression analysis were used to analyze dates.Results:The total prevalence of spontaneous knee joint osteoarthritis was 12.1% with 2.5% and 2.1% for right and left knees,respectively.The prevalence of knee joint osteoarthritis in wom- en was 2.5 times of that in men (17.2% vs 6.8%,P=0.000).the osteophyte prevalence in women was 2.3 times of that in men (26.5% vs 11.4%,P=0.000).The prevalence of knee joint osteoarthritis and osteophyte increased with the growth of age.So did the symptomatic knee,except for the age group of 56- 60 years and 66-70 years.The prevalence of symptomatic knee joint for urban area was significantly higher than that for rural area (56.3% vs 45.3%,P=0.003).In women,the prevalence of knee joint os- teoarthritis increased significantly with the increasing of body mass index,which had not been observed in men.Female and obesity are the risk factors for osteoarthritis,but bean and its products and meat could prevent the osteoarthritis.Conclusion:Old age,female and obesity serve as risk factors for knee joint os- teoarthritis. 展开更多
关键词 OSTEOARTHRITIS KNEE SPONTANEOUS EPIDEMIOLOGY middle and old aged
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The foraging behavior of Japanese macaques Macaca fuscata in a forested enclosure: Effects of nutrient composition,energy and its seasonal variation on the consumption of natural plant foods 被引量:3
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作者 M.Firoj JAMAN Michael A.HUFFMAN Hiroyuki TAKEMOTO 《Current Zoology》 SCIE CAS CSCD 北大核心 2010年第2期198-208,共11页
In the wild, primate foraging behaviors are related to the diversity and nutritional properties of food, which are affected by seasonal variation. The goal of environmental enrichment is to stimulate captive animals t... In the wild, primate foraging behaviors are related to the diversity and nutritional properties of food, which are affected by seasonal variation. The goal of environmental enrichment is to stimulate captive animals to exhibit similar foraging behavior of their wild counterparts, e.g. to extend foraging time. We conducted a 12-month study on the foraging behavior of Japanese macaques in a semi-naturally forested enclosure to understand how they use both provisioned foods and naturally available plant foods and what are the nutritional criteria of their consumption of natural plants. We recorded time spent feeding on provisioned and natural plant foods and collected the plant parts ingested of their major plant food species monthly, when available. We conducted nutritional analysis (crude protein, crude lipid, neutral detergent fiber-‘NDF', ash) and calculated total non-structural carbohydrate - ‘TNC' and total energy of those food items. Monkeys spent 47% of their feeding time foraging on natural plant species. The consumption of plant parts varied significantly across seasons. We found that leaf items were consumed in months when crude protein, crude protein-to-NDF ratio, TNC and total energy were significantly higher and NDF was significantly lower, fruit/nut items in months when crude protein and TNC were significantly higher and crude lipid content was significantly lower, and bark items in months when TNC and total energy were higher and crude lipid content was lower. This preliminary investigation showed that the forested enclosure allowed troop members to more fully express their species typical flexible behavior by challenging them to adjust their foraging behavior to seasonal changes of plant item diversity and nutritional content, also providing the possibility for individuals to nutritionally enhance their diet . 展开更多
关键词 NUTRITION Food consumption Semi-natural vegetation Provisioned foods Captive primates ENRICHMENT
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Inverse kinematic optimal design of 6-DOF parallel manipulators 被引量:2
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作者 张义凤 姚郁 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2008年第1期18-22,共5页
To obtain the required articular velocities as lower as possible for the given kinematics of the moving platform, this paper focuses on this kind of articular velocities optimization of 6-DOF parallel manipulators. Ba... To obtain the required articular velocities as lower as possible for the given kinematics of the moving platform, this paper focuses on this kind of articular velocities optimization of 6-DOF parallel manipulators. Based on the inverse kinematic analysis, the H∞ norm of the weighted Jacobian matrix was adopted as the performance index to minimize the articular velocities, and then the optimal design problem was formulated to find a manipulator geometry that minimized the global performance index with the constraints of the workspace and structural parameters limits. Since the optimal design problem is a constrained nonlinear optimization problem without explicit analytical expressions, the genetic algorithm was applied to numerically solve the problem. Simulation results indicate that the articular velocities of the optimal manipulators can be the minimum while the kinematic reauirements of the moving platform are satisfied. 展开更多
关键词 parallel manipulator articular velocity optimal design
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Monitoring actual performance of ground source heat pump system using GPRS-based data transmission: A case analysis in Tangshan 被引量:2
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作者 杜红普 孔祥飞 +1 位作者 李敏 齐承英 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第4期1554-1562,共9页
The energy efficiency monitoring is an essential precondition for ground source heat pump system's controlling and energy saving operation. Based on the data monitoring applied in the school building, this work is... The energy efficiency monitoring is an essential precondition for ground source heat pump system's controlling and energy saving operation. Based on the data monitoring applied in the school building, this work is focused on the parameters acquisition and operation analysis of the GSHP system in Tangshan. Results show the average COPs(coefficient of performance) are2.85 and 2.70 in summer and winter, respectively, and heat(cold) unbalance underground existed after whole year operation. The analysis of data also indicates that the direct borehole air-conditioning saved some power consumption obviously in the early stage of summer and energy saving of the GSHP system depended remarkably on its operation and management level. Besides the observation points of ground temperature are laid for a large-scale GSHP system, and the hydraulic balance of the pipes group needs to be concerned specially in safeguarding better reliability. 展开更多
关键词 ground source heat pump monitoring operation performance
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Influence of void space on microscopic behavior of fluid flow in rock joints 被引量:3
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作者 Zhang Zhenyu Jan Nemcik +1 位作者 Ren Ting Zhang Jun 《International Journal of Mining Science and Technology》 SCIE EI 2014年第3期335-340,共6页
Advanced microfluidic technology was used to examine the microscopic viscous and inertial effects evolution of water flow in rock joints. The influence of void space on fluid flow behaviour in rock joints under differ... Advanced microfluidic technology was used to examine the microscopic viscous and inertial effects evolution of water flow in rock joints. The influence of void space on fluid flow behaviour in rock joints under different flow velocities was experimentally investigated at the micro scale. Using advanced fabrication technology of microfluidic device, micro flow channels of semicircular, triangular, rectangular and pentagonal cavities were fabricated to simulate different void space of rock joints, respectively. Using the fluorescence labelling approach, the trajectory of water flow was captured by the microscope digital camera when it passed over the cavity under different flow velocities. The flow tests show that the flow trajectory deviated towards the inside of the cavity at low flow velocities. With the increase in flow velocity, this degree of flow trajectory deviation decreased until there was no trajectory deviation for flow in the straight parallel channel. The flow trajectory deviation initially reduced from the void corner near the entrance. At the same time, a small eddy appeared near the void corner of the entrance. The size and intensity of the eddy increased with the flow velocity until it occupied the whole cavity domain. The gradual reduction of flow trajectory near the straight parallel channel and the growth of eddy inside the cavity reflect the evolution of microscopic viscous and inertial forces under different flow velocities.The eddy formed inside the cavity does not contribute to the total flow flux, but the running of the eddy consumes flow energy. This amount of pressure loss due to voids could contribute to the nonlinear deviation of fracture fluid flow from Darcy's law. This study contributes to the fundamental understanding of non-Darcy's flow occurrence in rock joints at the micro scale. 展开更多
关键词 Water flow Void space Joint flow Electron microscopy
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Effects of photoperiod on daily activity rhythm of juvenile sea cucumber, Apostichopus japonicus (Selenka) 被引量:8
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作者 董贯仓 董双林 +1 位作者 田相利 王芳 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第5期1015-1022,共8页
In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a popul... In nature, Apostichopus japonicus exhibits a behavioral characteristic of emerging at night and sheltering during the day. Hence, it was commonly believed that longer and darker light conditions are better for a population of A. japonicus. In aquaculture situations therefore, animals have commonly been cultured without lighting, especially during juvenile-hatching culture. However, how the length of darkness each day affects .4.japonicus and what the mechanism is of behavioral response of A. japonicus to different photoperiods remain unclear, and are specifically addressed in this study. We applied nine photoperiod treatments (light:dark (LD) cycles at 0:24, 3:21, 6:18, 9:15, 12:12, 15:9, 18:6, 21:3, and 24:0 under 500Ix) to 60 individuals (29.73±0.23 g) per treatment (with 3 replicates). The enviroramental conditions were set as: water temperature = 16.9±0.3℃, dissolved oxygen〉6.0 rag/L, ammonia〈0.3 mg/L, pH=7.8-8.2, and salinity=30-32. Under experimental conditions of continuous darkness as well as continuous light, cyclic nocturnal activity patterns of A. japonicus (viz. the animals emerged and fed at night and sheltered during the day) were observed. However, they spent more and less time, respectively, moving and feeding under continuous darkness and continuous light, than those under a natural light cycle. Under photoperiods with 6-12 h of light, the animals showed one sheltering behavior transition and two emerging behavior transitions. These behavior transitions appeared to be governed by some internal physiological factors and induced by daily light variation. The behavior of the animals was significantly affected by different photoperiods, and the distribution rate (DR) of the animals emerging at "daytime" increased with lengthening "light time" (except for the LD 3:21 cycle). We also found that there was no significant difference in mean DR per day under LD cycles of 6:18, 9:15, 15:9, and 12:12. Mean DRs per day were significantly lower for these photoperiods, than for those under LD cycles of 0:24 and 3:21, and significantly higher than for those under LD cycles of 18:6, 21:3 and 24:0. These results imply that 6-15 h light per day were the similar photoperiods to natural sunlight. From the viewpoint of activity and feeding behaviors, these might be the optimal photoperiods for rearing A. japonicus. 展开更多
关键词 Apostichopusjaponicus daily behavior PHOTOPERIOD
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Global and Regional Impacts of Vegetation on the Hydrological Cycle and Energy Budget as Represented by the Community Atmosphere Model (CAM3) 被引量:1
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作者 XU Zhongfeng ZENG Gang FU Congbin 《Atmospheric and Oceanic Science Letters》 2009年第2期85-90,共6页
The effects of vegetation and its seasonal variation on energy and the hydrological cycle were examined using a state-of-the-art Community Atmosphere Model (CAM3). Three 15-year numerical experiments were completed... The effects of vegetation and its seasonal variation on energy and the hydrological cycle were examined using a state-of-the-art Community Atmosphere Model (CAM3). Three 15-year numerical experiments were completed: the first with realistic vegetation characteristics varying monthly (VEG run), the second without vegetation over land (NOVEG run), and the third with the vegetation characteristics held at their annual mean values (VEGMEAN run). In these models, the hydrological cycle and land surface energy budget were widely affected by vegetation. Globaland annual-mean evapotranspiration significantly increased compared with the NOVEG by 11.8% in the VEG run run, while runoff decreased by 13.2% when the realistic vegetation is incorporated. Vegetation plays different roles in different regions. In tropical Asia, vegetation-induced cooling of the land surface plays a crucial role in decreasing tropical precipitation. In middle latitudes and the Amazon region, however, the vegetation-induced increase of evapotranspiration plays a more important role in increasing precipitation. The seasonal variation of vegetation also shows clear influences on the hydrological cycle and energy budget. In the boreal mid-high latitudes where vegetation shows a strong seasonal cycle, evapotranspiration and precipitation are higher in the summer in the VEG run than in the VEGMEAN run. 展开更多
关键词 VEGETATION seasonal variation hydrological cycle energy budget regional climate
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Optical A/D Quantizer Scheme Based on Parallel Phase Mod ulators
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作者 LI Zheng 《Semiconductor Photonics and Technology》 CAS 2005年第3期161-165,共5页
A high-speed and high-resolution optical A/D quantizer is proposed.Its architecture is discussed.Bit circuits are built by using the phase modulators in parallel.Based on the different character of the half-wave volta... A high-speed and high-resolution optical A/D quantizer is proposed.Its architecture is discussed.Bit circuits are built by using the phase modulators in parallel.Based on the different character of the half-wave voltage for every phase modulator and the polarized bias design of incident light,the RF input signal is coled and transmitted in the form of optical digital signal.According to the principle of the architecture,the high-resolution quantizers with 8-bit and 12-bit,et al.are built,which operate at 100 GS/s.Their quantization noise is invariable almost with bit circuits increasing.The simulation result of 4-bit A/D quantizer is also given. 展开更多
关键词 Optical A/D quantizer PARALLEL Photonic sampling Optical data processing Traveling wave phase modulation
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A KAD Network Evolution Model Based on Node Behavior
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作者 WANG Jian FENG Weisen 《China Communications》 SCIE CSCD 2014年第10期67-73,共7页
An evolution model of KAD Dynamic Model Network(KDMN) is proposed to study the reason of hot node and simulate the process of network evolution based on node behavior from a holistic perspective.First,some symbols and... An evolution model of KAD Dynamic Model Network(KDMN) is proposed to study the reason of hot node and simulate the process of network evolution based on node behavior from a holistic perspective.First,some symbols and meanings are introduced to describe nodes relationship and network states at a time step.Second,some evolution rules for network are formulated when node behaviors of join,exit,routing table update,data retrieval and content index distribution happen with different contextual scene in KAD network.In addition,a lightweight simulator is designed to implement the KDMN model.Moreover,an example of how to use the simulator to simulate the network changes in order to observe the result is described in detail.Finally,the KDMN is applied to analyze the reason for the formation of hot nodes in the BT and eMule network in the experiment.The different evolution principles of local priority,global priority and hybrid random are adopted based on the provision of network protocol of BT and eMule.The result of this experiment demonstrates that there are some hot nodes exist in the KAD network.However,the principle of hybrid random can effectively alleviate the phenomenon that a node is widely linked with others compared with global and local priority. 展开更多
关键词 KAD evolution model nodebehavior SIMULATOR
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Analytical model of shear mechanical behaviour of bolted rock joints considering influence of normal stress on bolt guide rail effect 被引量:2
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作者 ZHENG Luo-bin WANG Liang-qing ZHU Lin-feng 《Journal of Central South University》 SCIE EI CAS CSCD 2021年第5期1505-1518,共14页
Rock bolts have been widely used in slopes as a reinforcement measure.Modelling the shear mechanical behaviours of bolted rock joints is very complicated due to the complex factors that affect the axial force and shea... Rock bolts have been widely used in slopes as a reinforcement measure.Modelling the shear mechanical behaviours of bolted rock joints is very complicated due to the complex factors that affect the axial force and shear force on the bolts.Rock bolts under shear action exhibit the guide rail effect;that is,the rock mass slides along the rock bolt as if the rock bolt is a rail.The normal stress can inhibit the guide rail effect and reduce the axial force on bolts.However,this factor is not considered by the existing analysis models.Shear tests of bolted joints under different normal stresses were carried out in the laboratory.During the test,the axial force on each point monitored on the bolt was recorded by a strain gauge,and the attenuation trend of the strain was studied.An analytical model that considers the inhibition of the bolt rail effect due to an increase in the normal stress was proposed to predict the shear mechanical behaviour of rock bolted joints.The new model accommodates the bolt shear behaviours in the elastic stage and plastic stage,and the estimated values agree well with the results of the direct shear tests in the laboratory.The validation shows that the proposed model can effectively describe the deformation characteristics of the bolts in the shear tests. 展开更多
关键词 bolted rock joints shear test shear behaviour analysis model
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Analysis of Energy-saving Behavior among University Students in Vietnam
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作者 Naohiro Goto Shota Tokunaga +1 位作者 Dinh Thi Nga Van Ho Thi Thanh 《Journal of Environmental Science and Engineering(B)》 2016年第7期355-362,共8页
Currently, in the course of serious environmental problems where the cause is anthropogenic, such as global wanning, not only the technology and policies but also the promotions of pro-environmental behavior are requi... Currently, in the course of serious environmental problems where the cause is anthropogenic, such as global wanning, not only the technology and policies but also the promotions of pro-environmental behavior are required. However, previous studies reported a gap between high environmental awareness and behavior. So to promote this practice, it is necessary to clarify the determinants that lead to practice. Because of the rapid economic growth in developing countries, including Vietnam, pollution problems and energy consumption are of major importance. This study aims to propose methods to promote pro-environmental practices based on a questionnaire and statistical analysis that investigated university students in Vietnam's Ho Chi Minh city. From the factor analysis, in actions to do with the power-saving behavior of standby power and home electronics, and the use of air conditioning, four evaluation criteria including effectiveness, cost feasibility, convenience, and social norms are extracted. The covariance structure analysis showed that the evaluation of convenience represented the strongest causal relation to a given power-saving action, and the action, in turn, can lead to improvements in most practical activities so as to enhance their convenience. Finally, several methods to save energy are proposed based on the results of the questionnaire. 展开更多
关键词 Environmental behavior INTENTION factor analysis questionnaire investigation covariance structure analysis.
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