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The Actuality and Prospect of Meteorological Service Technology for Solar Greenhouse 被引量:2
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作者 黎贞发 李春 刘淑梅 《Meteorological and Environmental Research》 CAS 2010年第3期112-116,共5页
The solar greenhouse's construction and its demand on meteorological service in the process of production management in China were analyzed,and the current situation of meteorological service on it was summarized.... The solar greenhouse's construction and its demand on meteorological service in the process of production management in China were analyzed,and the current situation of meteorological service on it was summarized.Combined with the trend of related technology,the future development of solar greenhouse meteorological service was prospected. 展开更多
关键词 Solar greenhouse Meteorological service actuality PROSPECT China
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Evidence-based Landscape Design of University Campus:Relationship Between Characteristics of Outdoor Environments and Actual Uses of Students
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作者 Fu Xing-yuan Qin Tong +4 位作者 Sun Hao-nan Shi Yang-ning Meng Xiang-dong Wang Yao Zou Tie-an 《Journal of Northeast Agricultural University(English Edition)》 CAS 2020年第2期152-158,共7页
Several studies have shown a positive relationship between high quality outdoor environments and users’health.Education of agricultural professionals also demands high quality outdoor environments in order to promote... Several studies have shown a positive relationship between high quality outdoor environments and users’health.Education of agricultural professionals also demands high quality outdoor environments in order to promote students’wellbeing,which in turn supports scientific researches.This study analyzed relationship between students’actual uses and campus outdoor environments,identified what environmental characteristics that students prefered,how they used and why they participated in the outdoor activities.The results could be used as guidance of campus design and management.Investigation of three universities in Harbin provided 686 valid questionnaires.The results suggested that health awareness effectively promoted students’use frequencies of outdoor environments.Environment with"natural"and"cultural"characteristics,especially undulating landform,vibrant plants and landmarks in a serpentins design style attracted more uses.Female students showed more preferences on social interaction activities than males.Students who had good economic consumption levels and participated in outdoor activities frequntly in childhood prefered to join all the kinds of activities after university enrollment. 展开更多
关键词 outdoor environment actual use PLACE landscape design university campus
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Evaluation of Actual Evapotranspiration and Crop Coefficient in Carrot by Remote Sensing Methodology Using Drainage and River Water to Overcome Reduced Water Availability
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作者 Ali H. Hommadi Nadhir Al-Ansari +2 位作者 Hatem H. Hussien Rafat N. Abd Algan Ghaith M. Ali Majed 《Engineering(科研)》 CAS 2023年第5期352-366,共15页
Searching for alternative methods for traditional irrigation is World trend at days due to a reduction in water and increased of drought due to climate changes therefore farmers need use modern methods of scheduling w... Searching for alternative methods for traditional irrigation is World trend at days due to a reduction in water and increased of drought due to climate changes therefore farmers need use modern methods of scheduling water and minimizing water losses while also increasing yield. To meet the future increasing demands water and food there is a need to utilize alternative methods to reduce evaporation, transpiration and deep percolation of water. Any countries use recycled water (drain and sewage) and desalination water from the sea or drains to irrigate crops plus computing actual crop evapotranspiration (ET<sub>c</sub>) so as to calculate the amount of water to apply to a crop. The paper aims to assess the actual evaporation and evaporation coefficient of carrots, by planting carrots in a field and the crop was exposed to several sources of water (DW and RW) and comparing ET<sub>c</sub>, K<sub>c</sub> and production among plots of three sites (A, B and C). The study used two types of irrigation water (drain water (DW) and river water (RW)). The results were to monthly rate and accumulated actual evapotranspiration to C (irrigation by RW only) more than A (67% RW and 33% DW) and B (17% RW and 83% DW) via 7% and 58%, respectively. The yield to C more than A and B by 17% and 75%, respectively. In conclusion the use of DW can cause a reduction in crop consumptive of carrot crops also causes a reduction in yield, crop length, root length, root size, canopy of crop, number of leaves and biomass of the plant therefore, the drainage water needs to treated before irrigating crops And making use of it to irrigate the fields and fill the shortfall in the amount of water from the river. The drain water helped on filling the water shortage due to climate changes and giving production of carrot crop but less than river water. 展开更多
关键词 CARROT Reference Evapotranspiration actual Evapotranspiration (ETa) Marginal Water Crop Coefficient Landsat Satellite
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The feasibility of the actual combat application of the traditional martial arts techniques in modem combat challenge
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作者 Xue Shifa 《International Journal of Technology Management》 2015年第12期30-31,共2页
The traditional Chinese martial arts are the pride of the Chinese national specialties, but with the development of the western modem combat, some traditional martial arts bias appeared, such as the argument of the re... The traditional Chinese martial arts are the pride of the Chinese national specialties, but with the development of the western modem combat, some traditional martial arts bias appeared, such as the argument of the real fight of the traditional martial arts. This paper starts from the traditional historical origin, and analyzes the actual combat possibility of traditional martial arts to study the feasibility of the actual combat application of the traditional martial arts techniques in modem combat challenge. 展开更多
关键词 the traditional martial arts techniques modem fight challenge in actual combat the feasibility
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Development and Actuality of Life Cycle Cost Technique in China
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作者 GENG Jun-bao JIN Jia-shan LUO Yun WU Yi-liang 《International Journal of Plant Engineering and Management》 2012年第2期95-103,共9页
Life cycle cost technique is a powerful tool to make a scientific decision and a useful method of advancing the continuable development of the society. In this paper, development course, application actuality and up-t... Life cycle cost technique is a powerful tool to make a scientific decision and a useful method of advancing the continuable development of the society. In this paper, development course, application actuality and up-to-date research trends of life cycle cost technique in China are summarized. Some suggestions are given on how to general- ize the application of life cycle cost technique which are used as the reference to study life cycle cost technique. 展开更多
关键词 life cycle cost technique development course application actuality up-to-date research trends
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Wings-FDY一步法生产ITY的工艺研究
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作者 周龙 余锡攀 +2 位作者 李振宇 孙建杰 杜杨洋 《聚酯工业》 CAS 2024年第3期26-28,共3页
通过设备改造及工艺优化,成功实现了ITY在Wings-FDY设备上一步法生产。研究结果表明:风压设定为30 Pa,调整纺丝/卷绕上油比例为6:4,预热辊温度51℃,定型辊温度124℃,拉伸倍数3.2,卷绕速度3550 m/min时,ITY 148dtex/108f纺况稳定,物理指... 通过设备改造及工艺优化,成功实现了ITY在Wings-FDY设备上一步法生产。研究结果表明:风压设定为30 Pa,调整纺丝/卷绕上油比例为6:4,预热辊温度51℃,定型辊温度124℃,拉伸倍数3.2,卷绕速度3550 m/min时,ITY 148dtex/108f纺况稳定,物理指标均匀,满足客户定制化的产品需求。 展开更多
关键词 ity Wings-FDY 设备改造
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Evaluation of Tourist's Satisfaction Degree of Dongda Hot Spring Resort Area in Xi'an City
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作者 同勤学 杨瑞 《Journal of Landscape Research》 2009年第9期69-73,共5页
Tourist's satisfaction degree is one of the important indexes to evaluate the service quality of scenic spot.Taking Xi'an Dongda Hot Spring Resort Area for an example,with the expectation difference theory and... Tourist's satisfaction degree is one of the important indexes to evaluate the service quality of scenic spot.Taking Xi'an Dongda Hot Spring Resort Area for an example,with the expectation difference theory and customers' satisfaction evaluation model as the theoretical basis of the research,the overall satisfaction degree of tourists to hot spring resort area,and the actual sensation accomplishments and the expectation difference of each service index were analyzed by using regression analysis and paired sample t test method.The results showed:① The overall satisfaction degree of tourists to the resort area was higher.There were remarkable correlation among three variables:the sensation value,the overall satisfaction degree,and the tourist's loyalty degree;② Generally,the sensation actual accomplishments of 15 service appraisal factors were higher than the expectation value.According to the characteristics,these 15 service appraisal factors were divided into 5 groups.Some unsatisfactory aspects were found out,and the corrective measures were put forward. 展开更多
关键词 Hot Spring RESORT Area Tourists’ SATISFACTION degree EXPECTATION SENSATION value SENSATION actual accomplishments
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Application of Farming Culture in the Construction of Eco-Park —A Case Study of Baiyunzhai Demonstration Eco-park in Chongqing City
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作者 董莉莉 《Journal of Landscape Research》 2011年第9期69-73,共5页
Definitions and features of eco-park and theme park were introduced as well as their differences, it was proposed that by applying cultural themes suited to regional ecological resources in the construction of eco-par... Definitions and features of eco-park and theme park were introduced as well as their differences, it was proposed that by applying cultural themes suited to regional ecological resources in the construction of eco-park, the eco-park could achieve not only desired ecological benefits, but also social and economic benefits, and the optimal comprehensive benefits. Design of Baiyunzhai Demonstration Eco-park was taken for an example, integration of eco-park and farming culture was confirmed as the nature, principles of "adaptation to actual conditions, amended protection and construction of plant system" proposed, three functional areas of "Colorful Forest Belt, Yiyun Health Maintenance Zone, Lakefront Meditation Zone" are given on the basis of actual terrains, planning highlights and desired landscape effects expounded to promote the value of regional cultures in Chongqing by building Baiyunzhai Eco-park. 展开更多
关键词 Integration Adaptation to actual conditions Amended protection System CONSTRUCTION EXPERIENTIAL FOLK activities AGGREGATION force
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Actual evapotranspiration of subalpine meadows in the Qilian Mountains, Northwest China 被引量:8
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作者 GAO Yunfei ZHAO Chuanyan +6 位作者 Muhammad W ASHIQ WANG Qingtao RONG Zhanlei LIU Junjie MAO Yahua GUO Zhaoxia WANG Wenbin 《Journal of Arid Land》 SCIE CSCD 2019年第3期371-384,共14页
As a main component in water balance,evapotranspiration(ET)is of great importance for water saving,especially in arid and semi-arid areas.In this study,the FAO(Food and Agriculture Organization)Penman-Monteith model w... As a main component in water balance,evapotranspiration(ET)is of great importance for water saving,especially in arid and semi-arid areas.In this study,the FAO(Food and Agriculture Organization)Penman-Monteith model was used to estimate the magnitude and temporal dynamics of reference evapotranspiration(ET0)in 2014 in subalpine meadows of the Qilian Mountains,Northwest China.Meanwhile,actual ET(ETc)was also investigated by the eddy covariance(EC)system.Results indicated that ETc estimated by the EC System was 583 mm,lower than ET0(923 mm)estimated by the FAO Penman-Monteith model in 2014.Moreover,ET0 began to increase in March and reached the peak value in August and then declined in September,however,ETc began to increase from April and reached the peak value in July,and then declined in August.Total ETc and ET0 values during the growing season(from May to September)were 441 and 666 mm,respectively,which accounted for 75.73%of annual cumulative ETc and 72.34%of annual cumulative ET0,respectively.A crop coefficient(kc)was also estimated for calculating the ETc,and average value of kc during the growing season was 0.81(ranging from 0.45 to 1.16).Air temperature(Ta),wind speed(u),net radiation(Rn)and soil temperature(Ts)at the depth of 5 cm and aboveground biomass were critical factors for affecting kc,furthermore,a daily empirical kc equation including these main driving factors was developed.Our result demonstrated that the ETc value estimated by the data of kc and ET0 was validated and consistent with the growing season data in 2015 and 2016. 展开更多
关键词 actual EVAPOTRANSPIRATION reference EVAPOTRANSPIRATION CROP coefficient METEOROLOGICAL FACTORS biotic FACTORS
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Non-probabilistic reliability method and reliability-based optimal LQR design for vibration control of structures with uncertain-but-bounded parameters 被引量:9
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作者 Shu-Xiang Guo Ying Li 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2013年第6期864-874,共11页
Uncertainty is inherent and unavoidable in almost all engineering systems. It is of essential significance to deal with uncertainties by means of reliability approach and to achieve a reasonable balance between reliab... Uncertainty is inherent and unavoidable in almost all engineering systems. It is of essential significance to deal with uncertainties by means of reliability approach and to achieve a reasonable balance between reliability against uncertainties and system performance in the control design of uncertain systems. Nevertheless, reliability methods which can be used directly for analysis and synthesis of active control of structures in the presence of uncertainties remain to be developed, especially in non-probabilistic uncertainty situations. In the present paper, the issue of vibration con- trol of uncertain structures using linear quadratic regulator (LQR) approach is studied from the viewpoint of reliabil- ity. An efficient non-probabilistic robust reliability method for LQR-based static output feedback robust control of un- certain structures is presented by treating bounded uncertain parameters as interval variables. The optimal vibration con- troller design for uncertain structures is carried out by solv- ing a robust reliability-based optimization problem with the objective to minimize the quadratic performance index. The controller obtained may possess optimum performance un- der the condition that the controlled structure is robustly re- liable with respect to admissible uncertainties. The proposed method provides an essential basis for achieving a balance between robustness and performance in controller design ot uncertain structures. The presented formulations are in the framework of linear matrix inequality and can be carried out conveniently. Two numerical examples are provided to illustrate the effectiveness and feasibility of the present method. 展开更多
关键词 Structural control Vibration control Robust control Linear quadratic regulator (LQR) Robust reliabil- ity Structural reliability
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Genetic variability and divergence studies in pod and seed traits of Pongamia pinnata(L.) Pierre., accessions in Bay Islands 被引量:4
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作者 I. Jaisankar M. Sankaran +1 位作者 D.R. Singh V. Damodaran 《Journal of Forestry Research》 SCIE CAS CSCD 2014年第2期351-358,共8页
In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducte... In this study, we assessed the variability in pod, seed traits and oil content of 24 accessions of Pongamia pinnata collected from different parts of the Andaman and Nicobar Islands, India. The experiment was conducted at the Central Agricultural Research Institute, Port Blair during 2010 to 2011. The variability studies for pod and seed traits revealed that, the accession CPT-6 collected from New Wandoor in South Andaman recorded the maximum values for eight traits viz. pod length (75.51 mm), pod width (34.62 mm), pod thickness (17.55 mm), 100 pod weight (770.33 g), seed width (21.23 mm), 100 seed weight (377.00 g), oil percentage (43.92%) and germination percentage (94.7%). However, the maximum seed length (26.46 mm) was recorded from CPT 2 and the maximum pod-seed ratio was obtained from CPT 13 and CPT 4 (2.50 and 2.44 respectively). The phenotypic and genotypic coefficients of variations were also close to each other for all traits, but the 100 pod and seed weight exhibited higher phenotypic and genotypic coefficient of variation than the other traits. Estimates of broad sense heritability ranged from 0.30 (for seed length) to 0.95 (pod length) and genetic ad- vance as percent of the mean ranged between 11.66% and 57.40% with seed length giving the lowest value and 100 pod weight giving the high- est value. Both the phenotypic and genotypic correlation between pod length, pod width, pod thickness, 100 pod weight, seed width and 100 seed weight and between pod thickness, 100 pod weight, seed width, 100 seed weight and germination percentage were found to be strong. On the basis of non hierarchical Euclidian cluster analysis, 24 accessions were grouped into six clusters. The maximum numbers of seven accessions were included in cluster VI. The maximum intra cluster distance (10.238)shown by cluster VI and the maximum inter cluster distance (17.021) between V and HI followed by III and II (15.942). Among the six clus- ters formed the cluster III recorded maximum oil percentage, 100 pod weight, 100 seed ,weight, pod length, pod thickness, pod width, seed width and. germination percentage, while cluster V recorded maximum pod seed ratio and germination percentage. The present findings suggest that the crossing between accessions of cluster V and cluster III will result in a wide spectrum of variability in subsequent generations. 展开更多
关键词 Pongamia pinnata correlation heritabi!ity genetic gain genetic divergence oil percentage
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Shakedown Criterion Employing Actual Residual Stress Field and Its Application in Numerical Shakedown Analysis 被引量:4
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作者 ZOU Zongyuan GUO Baofeng +2 位作者 LI Yinxiao JIN Miao ZHAO Shiyan 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2015年第5期919-927,共9页
Construction of the static admissible residual stress field and searching the optimal field are key tasks in the shakedown analysis methods applying the static theorem. These methods always meet dimension obstacles wh... Construction of the static admissible residual stress field and searching the optimal field are key tasks in the shakedown analysis methods applying the static theorem. These methods always meet dimension obstacles when dealing with complex problems. In this paper, a novel shakedown criterion is proposed employing actual residual stress field based on the static shakedown theorem. The actual residual stress field used here is produced under a specified load path, which is a sequence of proportional loading and unloading from zero to all the vertices of the given load domain. This ensures that the shakedown behavior in the whole load domain can be determined based on the theorem proposed by K6nig. The shakedown criterion is then implemented in numerical shakedown analysis, The actual residual stress fields are calculated by incremental finite element elastic-plastic analysis technique for finite deformation under the specified load path with different load levels. The shakedown behavior and the shakedown limit load are determined according to the proposed criterion. The validation of the criterion is performed by a benchmark shakedown example, which is a square plate with a central hole under biaxial loading. The results are consistent with existing results in the literatures and are validated by full cyclic elastic-plastic finite element analysis. The numerical shakedown analysis applying the proposed criterion avoids processing dimension obstacles and performing full cyclic elastic-plastic analysis under arbitrary load paths which should be accounted for appearing. The effect of material model and geometric changes on shakedown behavior can he considered conveniently. 展开更多
关键词 ELASTOPLASTIC finite element shakedown criterion specified load path actual residual stress field
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基于Unity 3D泥活字印刷虚拟仿真的设计与实现 被引量:2
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作者 徐秀梅 程明智 +1 位作者 史羽天 陈磊 《北京印刷学院学报》 2017年第2期35-38,共4页
为了弘扬和继承中国非物质文化遗产,提高人们对非物质文化遗产的关注度,了解现今虚拟现实技术的发展趋势,设计了一款基于Unity 3D引擎及其相关技术的泥活字印刷虚拟仿真应用软件。实现了将非物质文化遗产泥活字印刷的工艺流程与虚拟仿... 为了弘扬和继承中国非物质文化遗产,提高人们对非物质文化遗产的关注度,了解现今虚拟现实技术的发展趋势,设计了一款基于Unity 3D引擎及其相关技术的泥活字印刷虚拟仿真应用软件。实现了将非物质文化遗产泥活字印刷的工艺流程与虚拟仿真技术相结合。经虚拟仿真实验证明,该应用设计软件不仅能实现活字印刷的传统工艺流程的虚拟仿真,基于该项技术,还可以设计更多的非物质文化遗产进行场景复原式仿真,是虚拟仿真技术在非物质文化遗产保护领域中的一次应用性的探索。 展开更多
关键词 非物质文化遗产 UNity 3D 泥活字印刷术 虚拟仿真
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Comparison of pan evaporation and actual evaporation estimated by land surface model in Xinjiang from 1960 to 2005 被引量:6
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作者 刘波 马柱国 +1 位作者 徐晶晶 肖子牛 《Journal of Geographical Sciences》 SCIE CSCD 2009年第4期502-512,共11页
Pan evaporation,an indictor of potential evaporation,has decreased during the last several decades in many parts of the world;the trend is contrary to the expectation that the increase of actual evaporation will accom... Pan evaporation,an indictor of potential evaporation,has decreased during the last several decades in many parts of the world;the trend is contrary to the expectation that the increase of actual evaporation will accompany global warming,known as the pan evaporation paradox.What is the essential relationship between pan evaporation and actual evaporation? This is still an uncertain problem.In this paper,the trends of pan evaporation and actual evaporation are investigated using observational data and observation-constrained simulation results using NCAR Community Land Model(CLM) in Xinjiang from 1960 to 2005.Our analysis suggests that the decreasing trend of annual pan evaporation accompanies the increasing trend of annual actual evaporation,the tendencies of them both have statistical significance(at 99% level and at 95% level,respectively).We also find that there is the same turning point in precipitation,pan evaporation and actual evaporation of 1986,and either before the point or after,pan evaporation has inverse trend comparing with actual evaporation and precipitation.The above analysis indicates that pan evaporation and actual evaporation have complementary relationship.These results support the issue of evaporation paradox described by Brutsaert and Parlange(1998) and suggest that decrease of pan evaporation indicates an increase of actual evaporation in Xinjiang in the past half century.The correlation analysis shows that diurnal temperature range(DTR),wind speed,low cloud cover and precipitation are the most likely driving forces for the reduced pan evaporation and the ascending actual evaporation. 展开更多
关键词 XINJIANG pan evaporation actual evaporation numeral simulation
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An Analytical Study of Leibniz’s Secant and Tangent on the Logical Basis of Mathematical Infinity 被引量:2
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作者 ZHU Wu-jia GONG Ning-sheng DU Guo-ping 《Chinese Quarterly Journal of Mathematics》 CSCD 2011年第3期420-425,共6页
Refs 1 and 2 provide the definition of the concepts of‘potential infinity’(poi)and actual infinity(aci);Ref 3 discusses and verifies that poi and aci are a pair of contradictory opposites without intermediate(p,-p).... Refs 1 and 2 provide the definition of the concepts of‘potential infinity’(poi)and actual infinity(aci);Ref 3 discusses and verifies that poi and aci are a pair of contradictory opposites without intermediate(p,-p).The second part of this paper,i.e.,§2,further discusses the manners in which a variable x approaches infinitely to its limit x0 using the poi and aci methods and concludes that,in any system compatible with both poi and aci, the two approaching manners are also a pair of contradictory opposites without intermediate (A,-A).Finally,on the basis of this conclusion,we reexamine the fundamental question of Leibniz’s Secant and Tangent Lines in calculus and the limit theory and offer our analysis and raise new questions. 展开更多
关键词 CALCULUS limit theory potential infinity actual infinity
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Comparative Study on Shearing Edge Quality Influence of the Change of Tool Geometry in Fine-Blanking for Non-homogeneous Materials 被引量:1
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作者 Y C Leung L C Chan T C Lee 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期117-118,共2页
Excellent quality of shearing edge implies that a s mo oth cutting edge without tearing will be observed on the whole edge surface. Thi s is one of the most significant features of the Fine-blanking process. To achi e... Excellent quality of shearing edge implies that a s mo oth cutting edge without tearing will be observed on the whole edge surface. Thi s is one of the most significant features of the Fine-blanking process. To achi eve such a superb blanking edge quality in fine-blanking, there actually involv es quite a large number of factors, such as blanking speed, processing material, product shape, lubrication and tool geometry, to be considered simultaneously d uring the operation. Nevertheless, the thorough investigations on different effe cts of those critical factors for different kinds of popular and applicable mate rial are rare and limited. Thus, the objective of this paper is mainly focused o n the study of the quality influence of tool geometry change in fine-blanking f or non-homogeneous materials. However, the most obvious change of the tool geo metry during the operation will be the essential variation of the nose radius of the punch. This is because the nose radius usually seriously deteriorates with the increasing service period in mass production which eventually causes the ent irely lose of the specific features of the fine-blanking process. Therefore, a tailor-made experimental study was carried out to investigate the relationship between the punch nose radius and the shearing edge quality, such as blanked edg e finish, burr height and die-roll height, during fine-blanking for different types of material. Five punches with each specified nose radius (Rp), 0.00 mm, 0.25 mm, 0.50 mm, 0.75 mm and 1.00 mm, and four kinds of blanking material ( Mil d steel SS400, Stainless steel AISI316L, Copper alloy UNSC16200 and Aluminium al loy AA6063 ) were employed throughout the study. Subsequently, features of the s heared edge surfaces and data of each experiment were observed and captured for further analysis in this research. Consequently, findings show that an increase of punch nose radius would produce a higher percentage of fracture of blanked ed ge and increase the amount of burr height. In overall comparison, it is found th at mild steel and copper alloy do provide better surface edge finish with higher percentage of sheared area and less burr height than that of stainless steel an d aluminium alloy. 展开更多
关键词 fine-blanking tool geometry shearing edge qual ity
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Numerical analysis of stability for mined-out area in multi-field coupling 被引量:5
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作者 罗周全 谢承煜 +3 位作者 周吉明 贾楠 刘晓明 徐海 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第2期669-675,共7页
There were differences between real boundary and blast hole controlling boundary of irregular mined-out area in underground metal mines. There were errors in numerical analysis of stability for goaf, if it was analyze... There were differences between real boundary and blast hole controlling boundary of irregular mined-out area in underground metal mines. There were errors in numerical analysis of stability for goaf, if it was analyzed as regular 3D mined-out area and the influence of coupling stress-seepage-disturbance was not considered adequately. Taking a lead zinc mine as the background, the model was built by the coupling of Surpac and Midas-Gts based on the goaf model precisely measured by CMS.According to seepage stress fundamental equations based on the equivalent continuum mechanical and the theory about equivalent load of dynamic disturbance in deep-hole blasting, the stability of mined-out area under multi-field coupling of stress-seepage-dynamic disturbance was numerically analyzed. The results show that it is more consistent between the numerical analysis model based on the real model of irregular 3D shape goaf and the real situation, which could faithfully reappear the change rule of stress–strain about the surrounding rock under synthetic action of blasting dynamic loading and the seepage pressure. The mined-out area multi-field coupling formed by blasting excavation is stable. Based on combination of the advantages of the CMS,Surpac and Midas-Gts, and fully consideration of the effects of multi-field coupling, the accurate and effective way could be provided for numerical analysis of stability for mined-out area. 展开更多
关键词 mined-out area measured actually multi-field coupling stress-seepage-disturbance stability for mined-out area
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Lateral dynamic flight stability of hovering insects: theory vs. numerical simulation 被引量:4
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作者 Yan-Lai Zhang Jiang-Hao Wu Mao Sun 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第1期221-231,共11页
In the present paper, the lateral dynamic flight stability properties of two hovering model insects are predicted by an approximate theory based on the averaged model, and computed by numerical simulation that solves ... In the present paper, the lateral dynamic flight stability properties of two hovering model insects are predicted by an approximate theory based on the averaged model, and computed by numerical simulation that solves the complete equations of motion coupled with the Naviertokes equations. Comparison between the theoretical and simulational results provides a test to the validity of the assumptions made in the theory. One of the insects is a model dronefly which has relatively high wingbeat frequency (164Hz) and the other is a model hawkmoth which has relatively low wingbeat frequency (26 Hz). The following conclusion has been drawn. The theory based on the averaged model works well for the lateral motion of the dronefly. For the hawkmoth, relatively large quantitative differences exist between theory and simulation. This is because the lateral non-dimensional eigenvalues of the hawkmoth are not very small compared with the non-dimensional flapping frequency (the largest lateral non-dimensional eigenvalue is only about 10% smaller than the non-dimensional flapping frequency). Nevertheless, the theory can still correctly predict variational trends of the dynamic properties of the hawkmoth's lateral motion. 展开更多
关键词 Insect - Hovering Lateral dynamic flight stabil- ity Averaged model Equations-of-motion Navier-Stokes simulation
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Mathematical Infinity and Medium Logic (I) --Logical-mathematical Interpretation of Leibniz's Secant and Tangent Lines Problem in Medium Logic 被引量:1
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作者 ZHU Wu-jia GONG Ning-sheng DU Guo-pin 《Chinese Quarterly Journal of Mathematics》 CSCD 2013年第1期41-46,共6页
From the perspective of potential infinity (poi) and actual infinity, Ref [4] has confirmed that poi and aci are in 'unmediated opposition' (P,﹁P ) whether in ZFC or not; it has further been proved that the m... From the perspective of potential infinity (poi) and actual infinity, Ref [4] has confirmed that poi and aci are in 'unmediated opposition' (P,﹁P ) whether in ZFC or not; it has further been proved that the manners in which a variable infinitely approaches its limit also satisfy the law of intermediate exclusion. With these results as theoretical bases, this paper attempts to provide an accurate and strict logical-mathematical interpretation of the incompatibility of Leibniz's secant and tangent lines in the medium logic system from the perspective of logical mathematics. 展开更多
关键词 CALCULUS limit theory medium logic potential infinitv: actual infinity
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Fluorodeoxyglucose uptake in absence of CT abnormality on PET-CT: What is it? 被引量:1
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作者 Yiyan Liu 《World Journal of Radiology》 CAS 2013年第12期460-467,共8页
The purpose of this article is to provide a pictorial review of the findings and interpretative pitfalls about focal fluorodeoxyglucose(FDG)uptake in the absence of corresponding computer tomography(CT)lesion or abnor... The purpose of this article is to provide a pictorial review of the findings and interpretative pitfalls about focal fluorodeoxyglucose(FDG)uptake in the absence of corresponding computer tomography(CT)lesion or abnormality on an integrated positron emission tomography(PET)-CT.The integrated CT images in the PET-CT scanner allow correct co-registration and fused imaging of anatomical and functional data.On FDG PET-CT imaging,a real pathologic process often demonstrates abnormal uptake associated with a visible corresponding CT lesion or abnormality.When focal uptake is seen on PET imaging but no corresponding anatomic abnormality is visualized on the integrated CT,one should always be aware of possible mis-registration or mismatch of the PET and CT images due to the patient’s respiratory or body motion.While most of the hot spots in the absence of corresponding anatomic abnormalities are artefactual or secondary to benign etiologies,some may represent small sized or early staged neoplasm or metastases,especially in the gastrointestinal tract and skeletons.Caution should be exercised to simply diagnose a pathology based on the presence of the uptake only,or exclude the disease based on the absence of anatomic abnormality. 展开更多
关键词 FLUORODEOXYGLUCOSE UPTAKE POSITRON EMISSION tomography-computer TOMOGRAPHY ARTEF actual UPTAKE MIS-REGISTRATION POSITRON EMISSION TOMOGRAPHY interpretation
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