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1.
Significant changes have taken place within the contemporary architecture since the 20th century: firstly the architecture turns from "thing" to "nothing",secondly the experience of architecture turns from logic to essence intuition,and thirdly the architecture turns from noun to verb,from which we find in surprise the sparks of the Chinese traditional thought which criticizes all the ready-made,especially the conceptual thought with its happening and generation,and shows a new non-subject-object-dimidiate,non-logical and fundamentally non-metaphysical perspective in theory.This made it possible for us to reconsider and reinterpret the contemporary architecture from a more original new perspective.  相似文献   
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针对汽车转向行驶时常因车速过快而引发侧翻事故这一问题,通过建立车辆转向行驶的力学模型,分别对刚性车体和考虑悬架作用车体在急转工况下的受力状况进行分析;在分析车辆转向时横向载荷转移、悬架运动等因素对横向力系数影响的基础上,将横向力系数的计算方法进行改进;根据横向力系数与车速间的关系,建立了基于横向力系数的汽车急转工况防侧翻临界安全车速计算模型;选用某型商用车结构参数为例,通过Matlab软件仿真的方法将所建立模型与其他4种弯道安全车速计算模型进行对比分析,该模型所得临界安全车速处于其他4种车速模型所得结果的区间内;同时,采用车辆动力学软件Truck Sim进行不同转弯半径下的车辆转向侧翻仿真对该模型进行验证,模型所得安全车速值比Truck Sim软件仿真所得侧翻临界车速值约小10%。该研究为急转工况下车辆的侧翻评价以及车辆转向行驶的主动安全控制提供了参考。  相似文献   
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长三角地区耕地非农化研究   总被引:3,自引:0,他引:3  
长三角地区越来越多的耕地被建设所占用,耕地保护面临着巨大的压力。为有效保护有限的耕地资源,探讨耕地非农化的动力机制就显得尤为必要。而当今的研究主要集中在对土地利用方式变化的驱动力分析上。因此,利用经济学的制度分析方法和均衡分析方法,初步探讨了耕地非农化的内在机制,并根据其转换的内在机制提出了4点建议。  相似文献   
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硫酸盐还原菌的分离与生态特点研究   总被引:3,自引:0,他引:3  
采用S培养基进行富集培养的方法对硫酸盐还原菌(SRB)进行了分离与鉴定。实验通过对SRB的生理和生化特性的了解,结合其生存条件和存在状态进行研究,得出主要的环境因素中pH值和温度对SRB的腐蚀作用的影响关系,并提出采用合适的环境因素来更好的控制SRB的生长代谢活动,得出有效的防治措施来控制硫酸盐还原菌引起的腐蚀,延长有关设备的正常使用寿命。  相似文献   
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通过研究水的垂直渗透对水稻返青、水稻分蘖、水稻产量的影响,提出通过完善排水工程、设施,定期深耕田地,改善土壤渗透性,为水稻高产奠定基础.  相似文献   
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Based on the Rice Fish Concurrent living theory and pond aquaculture high yield technology, combining Rice Fish Concurrent Farming technique in the model of pit pond aquaculture and the Rice Fish in turn Farming technique in the model of field pond aquaculture, the high quality and yield ecological technique model of early rice fish concurrent farming and late complete aquaculture in paddy field was established, which contain one submodel of fingerlings farming to juvenile and another submodel of juvenile fish farming to adult fish. The model demonstration base covering 20 hm2 paddy field was established in Songyang village, Gechuan town, Liancheng county of Fujian province. Production results showed: Early rice harvest average yield increased 22% very significantly (P 〈 0. 01 ) in both submodels, and 453 kg juvenile fish was produced per 667 m2 paddy field implementing the submodel of fingerlings farming to juvenile fish, whose production value and profit were 5 182¥ and 1 662 ¥ RMB, respectively, and were very significantly increased 2.5 times and 3.7 times (P 〈 0.01 ) respectively than planting only two harvests paddy without aquacuhure; 710 kg adult fish was produced per 667 m2 paddy field implementing the suhmodel of juvenile fish farming to adult fish, whose production value and profit were 6 428¥ and 2 005 ¥ RMB, respectively, and were very significantly increased 3.2 times and 4.7 times (P 〈 0. 01 ) respectively than planting only two harvests paddy without aquaculture; There were good economic, social and ecological benefit.  相似文献   
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To avoid the complex numerical calculation for the electromagnetic field and determine underground abnormality, a neural network based method is proposed. In consideration of turn off transmitter current, the effect of a linear ramp turn off current on transmitter is corrected. The characteristics of transient expression and the traditional calculation algorithm for apparent resistivity are analyzed, and a predigest structure of network is obtained based on the kernel expression. The three layer back propagation(BP) neural network is trained by using sample data in homogeneous half space, and its number in hidden layer was determined. The method proposed is compared with two traditional calculation methods with simulation experiments. The result demonstrates that BP neural network has a high speed of processing data and is useful in explanation of the transient electromagnetic method.  相似文献   
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选取了图书馆学情报学17种核心期刊2008年第一期作为调查对象.通过对其文后参考文献中析出文献著录情况的现状进行调研,对不规范的著录举例、分析,并提出了几点建议,以促参考文献的著录逐步走向规范化的轨道。  相似文献   
10.
This paper reports the turning performance of an articulated vehicle in which applying direct yaw-moment control is applied to reduce the turning radius. In the proposed method, a braking force is applied to the inner tires when the articulation angle reaches its maximum in turning, which generates a yaw-moment around the vehicle's centre of gravity. The yaw-moment allows the vehicle to turn in a small radius. To evaluate the performance in tight turns, experiments were conducted using a wheel loader on paved ground. The vehicle's turning radius, yaw rate and side-slip angle were determined from the data measured using two global positioning systems and a fibre-optic gyro sensor. In addition, results of a simulation were compared with experimental results from a test vehicle. The turning radius at a braking pressure of 4 MPa was at least 0.41 m smaller than that of 0 MPa. Experimental and simulated results proved that generating a yaw-moment by applying one-sided braking forces during turning decreases the turning radius.  相似文献   
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