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181.
集成化企业网络需求分析信息量化模型冯径沈苏彬顾冠群(东南大学计算机科学与工程系,南京210096)集成化企业网络是CIMS网络的典型网络,包括设计制造、控制和管理等各方面的网络集成[1,2].网络需求分析是网络设计的第一步[3],它不仅是整个网络设...  相似文献   
182.
在分析LF-VD-CC过程各阶段热平衡状况的基础上,开发了LF-VD-CC过程中钢液温度控制模型。用该模型模拟计算了LF-VD-CC过程的温度变化。结果表明,该模型对预报过程钢水温度,计算的命中率较高,可用于工业生产.  相似文献   
183.
Two national stalagmite standard (GBW04412, GBW04413) and one international coral standard (RKM_4) have been determined by using thermal ionization mass spectrometry (TIMS) method. The values of ( 234 U/ 238 U) act , ( 230 Th/ 234 U) act and age are all consistent in error range with the standard values obtained by using α spectrometry.  相似文献   
184.
The187Os/188Os ratios of spinel lherzolite xenoliths from Panshishan determined with N-TIMS are lower than that of the primitive mantle, which shows depleted mantle characteristics. Their positive correlation with Al2O3/MgO suggests that the geochemical behavior of trace elements Re and Os is similar to that of Al2O3 and MgO respectively during the magmatic evolution and Re-Os isotopic system is largely immune to mantle metasomatism. A model age of 2.8–3.4 Ga obtained by187Os/188Os-Al2O3/ MgO correlation might represent the homogeneous age of the mantle lithosphere beneath the area.  相似文献   
185.
Some test statistics of Kolmogorov type and Cramér-von Mises type based on projection pursuit technique are proposed for the testing problem of sphericity of a high-dimensional distribution. The limiting distributions of the test statistics are derived under the null hypothesis and under any fixed alternative. The asymptotic properties of bootstrap approximation are investigated. Furthermore, for computational reasons, an approximation for the statistics, based on the number theoretic method, is suggested. An erratum to this article is available at .  相似文献   
186.
Chronology of environmental events over East Asia during the past 130 ka   总被引:3,自引:0,他引:3  
In the transitional region between the Loess Plateau and deserts, 4 sections located respectively at Yuling, Hengshan, Dingbian and Huining of China are studied. The high-resolution paleoclimatic records obtained show that environmental events on varying time scales have happened over East Asia. These events are dated with the time scales established using the recently-developed approach of Automatic Orbital Tuning. This leads to the establishment of the chronology of the environmental events.  相似文献   
187.
The effects of calmoddin (CaM) antagonist W7-agarose, anti-CaM serum and exogenous purified CaM on pollen germination and tube growth ofForsythia suspensu were studied. The pollen germination and tube growth were inhibited or completely stopped by CaM antagonist W7-agarose. The addition of exogenous purified CaM stimulated pollen germination and tube growth, whereas the same amount of bovine serum albumin (BSA) had no effect. The inhibitory effects caused by W7-agarose and anti-CaM serum could be reversed completely by the addition of exogenous purified CaM. The tube growth of germinated pollen was also inhibited or completely stopped by W7-agarose. The results suggest that endogenous extracellular CaM initiates pollen germination and tube growth, whereas exogenous CaM enhances the above processes.  相似文献   
188.
Having reviewed the major classification systems proposed by various scholars across the world, it is found thatindica andjaponica underO. sativa L. are two major directions thoroughly differentiated from the Asian cultivated rice, forming the framework of the classification structure. A system withindica andjaponica as the only two subspecies is therefore reiterated. There are various ways to determine the indica-japonica identity of hybrid rice, but the “combined morphological trait index” (CMT index) method is more efficient and easier to handle, although the isozyme analysis, molecular marker analysis and grain quality assay methods are also feasible.  相似文献   
189.
以沥青砂浆材料为例,通过薄板的蠕变断裂及单轴拉伸蠕变的试验结果和数据分析,推求出沥青砂浆在不同温度下的断裂特性参数Γ和σmI1。  相似文献   
190.
The nuclear capsid protein gene (vp39) ofBombyx mori nuclear polyhedrosis virus (BmNPV) was amplified successfully by PCR technique and inserted into pGEM 3zf(+). The 5′ and 3′ terminal area of the amplified vp39 gene were sequenced with silver-staining dideoxy method. Bmvp39 gene was sub-cloned into the expression vector pRSET-A, and transformed intoE. coli BL21. This gene was highly expressed by IPTG induction. SDS-PAGE analysis showed that the expressed protein is about 38 kd, and the expressed amount reached maxium in 4 h with IPTG induction. Supported by the National Natural science Foundation of China and the Doctoral Foundation of Edn carto Committee Liu Deli: born in 1954, Doctoral Candidate from Huazhong Normal University To whom correspondence should be addressed: (027-7882712-2938)  相似文献   
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