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1.
Production logistics involve the co-ordination of ac tivities such as production and materials control (PMC), inventory management, p roduct life cycle management, etc. Those activities demand for an accurate forec asting model. However, the conventional methods of making sell and buy decision based on human forecast or conventional moving average and exponential smoothing methods is no longer be sufficient to meet the future need. Furthermore, the un derlying statistics of the market information change ...  相似文献   
2.
在已开发的重油催化裂化十一集总动力学模型的基础上,对参数估计方法进行了改进,建立了一步法确定模型动力学参数的方法,并通过一步法得到了MLC-500催化剂多产柴油裂化的动力学参数,模型的实验室验证表明,动力学参数是可靠的。  相似文献   
3.
Highly precise 40Ar39Ar dating results demonstrate that the ages of potash-rich volcanic rocks in western Shandong Province are 114.7-124.3 Ma, and that of the lamprophyres is 119.6 Ma. The potash-rich volcanic rocks have relatively high (87Sr/86Sr)i ratios ( 0.708715-0.711418)and distinctly negative εNd values ( -11.47 - -17.54), and are enriched in radiogenic lead (206Pb/204pb=17.341-17.622,207pb/204Pb=15.525-15.538, 208Pb/204pb = 37.563-37.684).Similarly, the lamprophyres also have quite low εNd values ( -11.57 - -19.64). Based on the fact that the Sr, Nd and Pb isotopic compositions of potash-rich volcanic rocks are very consistent with that of the clinopyroxene separates, and by integrating comprehensive analyses of their tectonic settings,and extensive comparisons of the Sr, Nd isotopic compositions with that of the related simultaneous rocks, it is concluded that the potash-rich volcanic rocks and lamprophyres in western Shandong Province were most possibly derived from the partial melting of enriched mantle which was caused by source contamination and metasomatism of subducted continental crustal materials.``  相似文献   
4.
在大型电力系统中存在有自生的甚低频系统振荡。它一旦产生,就会不断增强,从而导致发电机组丧失同步以致使系统解体。本文推出一种新颖的最优控制对策,用以消除低频振荡,而又不损伤鲁棒数值特性。数字模拟结果表明,所推出的控制器可作为消除低频振荡的有效手段。  相似文献   
5.
The Diplecogaster-ctenocrypta species-group is reviewed; it comprises two species. The clingfish Diplecogaster ctenocrypta from the Canary Islands is redescribed. The new species Diplecogaster tonstricula, a facultative cleaner of other teleosts, is described on the basis of eight specimens and colour photos from Senegal and the Canary Islands, eastern Atlantic Ocean. The species is small, apparently not exceeding 23 mm total length; it is characterised by having nine dorsal-fin rays, eight anal-fin rays, 24–25 pectoral-fin rays, 14–15 principal caudal-fin rays, 13–16 rakers on third gill arch, pelvic disc without lateral papillae in region A, disc region B with two rows of weak papillae, interorbital distance 4.1–4.6 in head length, distance between disc and anus 14–17% of SL, head and body with 10–13 narrow vertical brownish bars, cheek with a white ocellus surrounded by black, and with a small black spot in the middle. The new species is compared with other species of the genus; a key to the six known species of the eastern Atlantic, Mediterranean and Black Sea and South African genus Diplecogaster is presented. A checklist is provided for the species of Diplecogaster and their synonyms.  相似文献   
6.
基于室内火灾烟气层高度和温度模型,使用拉丁超立方抽样方法研究了火灾增长系数和最大热释放速率的不确定性对可用安全疏散时间(ASET)的影响.结果表明,对于相当于民用建筑一个防火分区的单室无排烟房间,当最大热释放速率在0~1MW时,其不确定性对ASET影响较大;当最大热释放速率为1~4MW时,火灾增长系数对ASET的影响大于最大热释放速率对ASET的影响;当最大热释放速率在4~8MW取值,仅考虑最大热释放速率的不确定性时,ASET为一确定值,此时热释放速率的不确定性对ASET的影响仅由火灾增长系数产生.  相似文献   
7.
催化裂化原料油的乳化过程   总被引:2,自引:0,他引:2  
将掺渣蜡油乳化成W/O乳液,作为催化裂化原料油,在二次雾化和分子解聚作用下,可显著改善原料油雾化状况,降低结焦和干气收率。研究了掺渣蜡油的乳化过程,包括乳化剂的单剂筛选和复配以及乳化工艺条件。结果表明,烷基酚聚氧乙烯醚(M-2)具有较好的乳化性能;乳化剂的复配能增加乳化原料油稳定性;适宜的掺水量是ω水=0.10-0.15,加剂量为ω乳化剂=0.001-0.00125;乳化温度70℃-80℃,乳液体系中水珠分布直径为5μm-10μm,乳化原粒油在80℃时油水分层时间达14d。  相似文献   
8.
运用重油催化裂化十一集总动力学模型的工业应用软件 RCCLK,对催化裂化装置掺炼焦化蜡油和焦化柴油的工况进行了模拟。结果表明 ,模拟预测计算结果能较好地符合催化裂化反应规律 ,为催化裂化掺炼焦化蜡油、柴油选择合理的操作条件提供了依据  相似文献   
9.
BackgroundIntheearly 195 0s,MortonandYen[1] developedthefibertracingmethodintheyarn .Theymixedsomedyedfibersintoyarnbeforecarding ,anddippedtheyarninachemicalreagentwithsimilarrefractiveindextoobservethedyedfibersintheyarnunderthemicroscope .Theconceptoffibe…  相似文献   
10.
含缺陷流变特体在破坏过程中存在热致磁效应,跟踪测量出这一热致磁感应强度,对含缺陷流变物体材料破坏机理的研究具有重要意义,介绍一种以单片机为核心的随动跟踪测量系统的研制及其应用,重点说明传感器的结构及跟踪测量方法,并给出主程序框图。  相似文献   
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