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排序方式: 共有991条查询结果,搜索用时 15 毫秒
101.
102.
一、工程概况 石门水利枢纽工程位于汉江支流褒河峡谷出口以上1.8公里处。南距汉中18公里。 本工程是以灌溉为主、结合发电等综合利用效益的大型水利枢纽,为褒河梯级开发的第 相似文献
103.
在软基地区修筑高速公路,路基的沉降和稳定是制约施工工期和行车安全的两大基本问题,汕汾高速公路的典型软基路段按照常规手段处理后,路基填筑至设计高度一半,出现裂缝,果断地采取了部分卸载-等待-再加载的措施,再加载后裂缝再度出现.经多方反复论证,采取压入预制砼管桩的处理方案,效果良好,本文对此进行介绍,并从软基监测的角度进行评价. 相似文献
104.
进化算法(EA)是模仿自然界生物进化或物种的社会行为而产生和发展的随机搜索方法,这种算法能够解决许多传统方法无法解决的大规模优化问题。本文简明介绍了三种基于进化的优化算法:遗传算法、蚁群优化算法和微粒群优化算法,并在原理、参数和应用方面对它们进行了对比。 相似文献
105.
我厂生产的ZLM30装载机,在传动系中所采用的CYB-30型液力变矩器是参考国外样机试制的,如图1所示。经过几年运行,发现该变矩器出现下列几个问题: 相似文献
106.
酵晟? 《有色冶金设计与研究》1994,(2)
家的审判机关,将本着严肃执法的精神,正确适用上述法律和行政法规,强化对知识产权的保护。下面,我重点介绍几个诉讼中的问题:0知识产权Intellectual Property32-34 14D923.4G117;1;GG117_1;杨金琪000400040004000130-32 12论目前商标 相似文献
107.
Francisco GONZ?LEZ-LONGATT Pawel REGULSKI Happy NOVANDA Vladimir TERZIJA 《电力系统自动化》2012,36(8):191-197
Future power system faces several challenges,one of them is the high penetration level of intermittent wind power generation,providing small or even no inertial response and being not contributing to the frequency stability.The effect of shaft stiffness on inertial response of fixed speed wind turbines is presented.Four different drive-train models based on the multi-body system are developed.The small-signal analysis demonstrates no significant differences between models in terms of electro-mechanical eigen-values for increasing shaft stiffness.The natural resonance frequency of drive-train torsion modes shows slightly different values between damped and undamped models,but no significant differences are found in the number-mass models.Time-domain simulations show the changes in the active power contribution of a wind farm based on a fixed speed wind turbine during the system frequency disturbance.The changes in the kinetic energy during the dynamic process are calculated and their contribution to the inertia constant is small and effective.The largest contribution of the kinetic energy is provided at the beginning of the system frequency disturbance to reduce the rate of the frequency change,it is positive for the frequency stability. 相似文献
108.
Stahl A Schellewald C Stavdahl ? Aamo OM Adde L Kirker?d H 《IEEE transactions on neural systems and rehabilitation engineering》2012,20(4):605-614
Cerebral palsy (CP) is a perinatally acquired nonprogressive brain damage resulting in motor impairment affecting mobility and posture. Early identification of infants with CP is desired to target early interventions and follow-up. During early infancy, distinct motion patterns occur which are highly predictive for later disability. These motor patterns can be observed and recorded. In this paper, a method to predict later CP based on early video recordings of the infants' spontaneous movements, applying optical flow and statistical pattern recognition, is presented. We extract motion information from video recordings of young infants using a total variation related optical flow method. By using wavelet analysis features from motion trajectories of points initiated on a regular grid were extracted and classified using a support vector machine. 相似文献
109.
为了研究高占比紫薯全粉面条的最佳制作条件,在单因素实验的基础上,选择紫薯全粉添加量、谷朊粉添加量、食盐添加量为自变量,紫薯全粉面条的熟断条率、感官评分为评价指标,利用Box-Behnken中心组合原理设计3因素3水平实验,研究各自变量交互作用及其对紫薯全粉面条品质的影响。实验结果表明,高占比紫薯全粉面条的最佳工艺条件为:紫薯全粉与小麦粉的比例为44:56、谷朊粉添加量为7.0%、食盐添加量1.6%。在此条件下紫薯全粉面条的熟断条率为0.42%,感官评分为84.08。经中试验证,此工艺可规模化生产。 相似文献
110.
Vlada B. Veljkovi? Ana V. Veli?kovi? Jelena M. Avramovi? Olivera S. Stamenkovi? 《中国化学工程学报》2019,27(7):1690-1698
The performances of the response surface methodology (RSM) in connection with the Box-Behnken, face central composite or full factorial design (BBD, FCCD or FFD, respectively) were compared for the use in modeling of the NaOH-catalyzed sunflower oil ethanolysis. The influence of temperature, catalyst loading, and ethanol-to-oil molar ratio (EOMR) on fatty acid ethyl esters (FAEE) content was evaluated. All three multivariate strategies were efficient in the statistical modeling and optimization of the influential process variables but BBD and FCCD realization involved less number of experiments, generating smaller costs, requiring less work and consuming shorter time than the corresponding FFD. All three designs resulted in the same optimal catalyst loading (1.25% of oil) and EOMR (12:1). The reduced two-factorinteraction (2FI) models based on the BBD and FCCD defined a range of optimal reaction temperature (25℃-75℃) and 25℃, respectively while the same model based on the 33 FFD appointed 75℃. The predicted FAEE content of about 97%-98.0% was close to the experimentally obtained FAEE content of about 97.0%-97.6% under the optimal reaction conditions. Therefore, the simpler BBD or FCCD might successfully be applied for statistical modeling of biodiesel production processes instead of the more extensive, more laborious and more expensive FFD. 相似文献