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91.
Tokar David M.; Withrow Jason R.; Hall Rosalie J.; Moradi Bonnie 《Canadian Metallurgical Quarterly》2003,50(1):3
Structural equation modeling was used to test theoretically based models in which psychological separation and attachment security variables were related to career indecision and those relations were mediated through vocational self-concept crystallization. In contrast to previous studies, which have found either weak or no support for a relation between separation or attachment security variables and career indecision, results based on a sample of 350 college students indicated that some components of separation and attachment security did relate to career indecision in a theoretically supportable direction. Results also revealed that regardless of whether global or component career indecision measures were used, separation and attachment security effects on indecision were at least partially mediated through vocational self-concept crystallization. The strongest mediated relations were observed for the effects of attachment anxiety and maternal separation. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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利用地下水模拟软件系统GMS,在反推入渗系数、蒸发系数的基础上,设定合理的边界条件,建立非稳定流数学模型,模拟计算浸没范围,并论述了选取适当参数对农业区、居民区布置减压井,通过检验减压井防渍效果,得出对于典型二元结构地层,采用减压井防渍是经济合理措施的结论. 相似文献
95.
复杂结构井的过套管测井技术应用 总被引:1,自引:1,他引:0
王贺林 《石油地球物理勘探》2006,41(3):357-361
过套管测井是在已下套管井中完成的用以解决油气层识别、储层物性参数计算为目的的测井系列,在复杂井中用来代替常规的裸眼测井,以便减少在大斜度井中的测井事故,缩短测井周期。本文介绍了几种常用的过套管测井技术,并将其应用于大港油田的庄海401井。结果表明,过套管测井不仅解决了油气层判别的问题,也提供了较准确的物性参数,同时降低了施工作业的难度,缩短了占井周期,这一点对海上钻井尤为重要。 相似文献
96.
We present a fictitious domain decomposition method for the fast solution of acoustic scattering problems characterized by a partially axisymmetric sound‐hard scatterer. We apply this method to the solution of a mock‐up submarine problem, and highlight its computational advantages and intrinsic parallelism. A key component of our method is an original idea for addressing a Neumann boundary condition in the general framework of a fictitious domain method. This idea is applicable to many other linear partial differential equations besides the Helmholtz equation. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
97.
W. J. PLUMBRIDGE Y. KARIYA 《Fatigue & Fracture of Engineering Materials & Structures》2004,27(8):723-734
With continuing miniaturisation, increased performance demands and the requirement to remove lead from solder alloys, the challenges to structural integrity and reliability of electronic equipment are substantial and increasing. This paper outlines typical features in electronic equipment of which the structural integrity community may be generally unaware. Potential failure modes in service are described, and the problems of scale and material characteristics are considered. Progress in the application of fracture mechanics to the life prediction of interconnections is reviewed. The limited evidence available suggests that the crack growth resistance of silver‐containing lead‐free solders is superior to that of the traditional Sn‐37Pb under cycle‐controlled conditions but there is no difference when time‐dependent conditions prevail. In several respects, it is contended that the electronics sector is faced with challenges at least equivalent to those encountered in gas turbines and nuclear power generation. 相似文献
98.
H. Oudadesse J. L. Irigaray Y. Barbotteau V. Brun Ph. Moretto 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2002,190(1-4):458-465
Bioactive glasses are used as coating biomaterials to facilitate anchorage of metallic prostheses implanted into the body. The aim of this work is to study the behavior of gel formed in contact with alloys and BVA and BVH bioactive glasses implanted. Cylinders of metallic implants composed by Ti, Al and V, are coated with bioactive glass. Three sheep were implanted for different time length: 3, 6 and 12 months in the femoral epiphysis. Results obtained with particle induced X-ray emission and scanning electron microscopy show that BVA coating induces a better contact between the metallic implant and bone. On the other hand, BVH coating prevents corrosion from the metallic implant. 相似文献
99.
隧道受震破壞調查分析與修復管理案例 总被引:1,自引:0,他引:1
就隧道震後之災損模式進行統計與災損原因研判,並利用數值分析方法研判安全性,就結構加固等改善措施之設計考量作詳細說明;另由於隧道結構物的損壞範圍大,且修復經費受限,必須藉由定期檢测進行長期維護管理,以防範意外發生。於此,利用Vidco-GIS自動化影像地理资訊系統之e化新技術,以動態及靜態影像紀錄隧道災損狀況,同時亦整合建置前期設計、施工圖及定期維護等資料,相關成果以資料庫方式纳入日常維護管理,以有限人力有效率地進行維護管理紀錄並随時掌握現況供作決策之明確參考。 相似文献
100.
赵新国 《石油地球物理勘探》1992,27(4):545-555
断块油田的油气聚集和分布,在很大程度上受各种类型的断层所控制。这种油田具有构造面貌复杂、含油层系多、油水关系复杂、含油丰度差别大等特点,给油气勘探和开发造成了许多困难和不便。目前,有关断块构造圈闭的统计尚无统一标准。以往所用的取值方法是沿用背斜圈闭的要素统计方法,不能适用于复杂的断块构造圈闭。本文以断层圈闭特点为基础,以影响圈闭性能的各种因素间的函数关系为依据,提出了具有较厚盖层和储层地区的断层圈闭要素的计算方法。将此法应用于东濮凹陷,取得了较高精度的含油圈闭面积。 相似文献