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911.
讨论了两个自旋为h/2的电子的能级,本征波函数的求解及粒子处于z轴上的概率问题.通过两种不同的的方法得到了粒子处于z轴负方向上的概率,加深了对耦合表象下两个电子自旋性质的掌握,拓宽了量子力学的理论计算的思路. 相似文献
912.
燃煤添加剂是提高煤燃烧效率的有效措施,对高效燃煤添加剂进行了燃烧对比试验,检验其在实践中的可行性与性能. 相似文献
913.
Three major methods currently in the use of determining vehicle speed based on wheel speeds,the minimum wheel speed,minimum wheel speed corrected by slope method and the Kalman filter method,are analyzed,with merits and defects of each approach stated. Through simulations,the Kalman filter method based on minimum wheel speed shows improved accuracy,in addition to better adaptivity to vehicle reference speed. It also can be used to acceleration ship regulation (ASR) in part-time four-wheel drive vehicles. 相似文献
914.
Steering control strategy for high-speed tracked vehicle with hydrostatic drive is designed based on analyzing the fundamental steering theories of the hydrostatic drive tracked vehicle. The strategy is completed by the cooperation between integrated steering control unit and pump & motor displacement controller. The steering simulation is conducted by using Simulink of Matlab. It is indicated that this steering control strategy can reduce the average vehicle speed automatically to achieve the drivers expected steering radius exactly in the case of ensuring not exceeding the system pressure threshold and no sideslip. 相似文献
915.
Neck injury is a severe problem in traffic accidents. While most studies are focused on the neck injury in rear and front impacts, few are conducted in side impact. This study focuses on the difference of neck injury under different postures and the difference of 7 cervical vertebras under the same posture using the method of prescribed structure motion(PSM). The analytical results show that the maximum changes of mean force and mean moment of 7 cervical vertebras under 8 different postures are 20% and 47% respectively. The variation of each cervical vertebra is different under different neck postures. Up cervical vertebras (C1-C4) and low cervical vertebras (C5-C7) suffer different forces and moments under the same neck posture. Generally speaking, No.6 (neck right leaning 40°) is the posture with lowest neck injury risk. 相似文献
916.
Fault-Diagnosis Method Based on Support Vector Machine and Artificial Immune for Batch Process 总被引:1,自引:1,他引:0
A new fault-diagnosis method to be used in batch processes based on multi-phase regression is presented to overcome the difficulty arising in the processes due to non-uniform sample data in each phase. Support vector machine is first used for phase identification, and for each phase, improved artificial immune network is developed to analyze and recognize fault patterns. A new cell elimination role is proposed to enhance the incremental clustering capability of the immune network. The proposed method has been applied to glutamic acid fermentation, comparison results have indicated that the proposed approach can better classify fault samples and yield higher diagnosis precision. 相似文献
917.
针对由某公司生产首次应用到核电上的SA508-3钢,采用膨胀法在Gleeble1500D热模拟机上测定了其焊接连续冷却转变的膨胀曲线,结合显微组织和硬度,获得了每个冷速下对应的相变点温度.结果表明,在0.015~0.05℃/s冷速范围内.为高温转变的铁素体和珠光体区,0.1~7℃/s冷速范围内,为中温转变的贝氏体区,20~80℃/s的冷速范围内,为低温转变的马氏体区;随着冷却速度的增大,硬度值也越来越大,0.015℃/s对应的硬度值为199 HV,80℃/s对应的硬度值为546 HV,这为制定合理的焊接工艺提供了依据. 相似文献
918.
探索基于木材的微观构造,提出通过测试木材的孔隙度预测木材的绝干密度,为木材绝干密度的测定提供了一种新的途径.通过观察木材的显微构造,进行图像处理,定量地分析木材各部位的力学性质,同时通过对组织比量的研究来探讨其与木材绝干密度的关系,对预测及解释木材的物理力学性能提供了依据. 相似文献
919.
MA Fengying 《中国矿业大学学报(英文版)》2010,20(3)
Coal mining monitoring system has been enforcing tests for the immunity of Electromagnetic Compatibility (EMC) since 2006.However,not all monitoring substations can pass the Electrical Fast Transient/Burst (EFT/B) immunity test and the explosion-proof test simultaneously.In order to enhance EMC,the EFT/B interfere transmission model was presented at the substation power port,after the EFT/B test method was used to analyze the monitoring substation power ports.Hence,a low-pass filter was designed by using the simulation software PIPICE and an anti-jamming method was proposed by way of a parallel connection of the discharge interfere circuit and the low-pass filter.The improved complex EMI filter was made up of an interference discharge device and a filter.The dynamic equivalent circuit was proposed for the EFT/B immunity test.As a result,the monitoring substation has passed the EFT/B immunity and explosion-proof tests with the complex filter.It is concluded that the complex EMI filter has significantly enhanced the immunity of the coal mining monitoring system. 相似文献
920.
大学校园的学风是学校师生整体精神面貌的全面反映,也是学生健康成才的软环境,但是当前和谐校园学风建设出现很多不和谐现象,主要原因是受到学习态度、学习环境和教学环境的影响。要通过加强特殊学生过程管理,发挥党员先锋模范作用和培养学生科技和社会实践能力等途径促进大学生综合素质的提高,推动和谐校园学风建设。 相似文献