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排序方式: 共有5713条查询结果,搜索用时 15 毫秒
51.
52.
基于负压波的管道泄漏检测与定位技术研究 总被引:10,自引:2,他引:10
管道输送因其具有独特的优点已经在各行各业中得到了广泛应用,但日益严重的泄漏问题不仅影响了管输的正常运行,也给人类的生命财产造成了极大的损失。探索一种有效的检测方法已经迫在眉睫。文章对基于负压波的管道泄漏检测与定位技术的方法进行了研究,说明了其优缺点,指出了基于负压波法的管道泄漏检测与定位结构模式识别系统具有很好的发展前景。 相似文献
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54.
多示例学习及其研究现状 总被引:2,自引:0,他引:2
较全面地介绍和分析了第4种机器学习框架的多示例学习(MIL).首先通过数学表达式对多示例学习进行描述,概括了其主要性质;然后总结了目前主要的求解多示例学习问题的算法,剖析了这些算法的主要思想;最后对多示例学习的未来发展作了展望. 相似文献
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56.
钢筋工程是钢筋混凝土工程中很关键的一个分项,钢筋的设计、加工及安装的好坏,直接影响工程的质量。在钢筋工程的设计与施工中,工程技术人员一般研读标准图集不够,或对钢筋工程的设计意图及施工工艺了解不是十分透彻,结果在钢筋的设计、加工及安装中出现许多质量隐患,不能引起工程界的足够重视。章针对钢筋工程在结构主梁与次梁的连接、框架柱与梁及剪力墙的连接、梁与板的连接、柱子纵向钢筋的加工、现浇板负筋的绑扎等部位和钢筋工程经常忽视的若干问题进行了分析,并提出了解决对策,供设计和施工人员参考。 相似文献
57.
Kubany Edward S.; Hill Elizabeth E.; Owens Julie A.; Iannce-Spencer Cindy; McCaig Mari A.; Tremayne Ken J.; Williams Paulette L. 《Canadian Metallurgical Quarterly》2004,72(1):3
This article describes a second treatment-outcome study of cognitive trauma therapy for battered women with posttraumatic stress disorder (PTSD; CTT-BW). CTT-BW includes trauma history exploration: PTSD education; stress management; exposure to abuse and abuser reminders; self-monitoring of negative self-talk; cognitive therapy for guilt; and modules on self-advocacy, assertiveness, and how to identify perpetrators. One hundred twenty-five ethnically diverse women were randomly assigned to immediate or delayed CTT-BW. PTSD remitted in 87% of women who completed CTT-BW, with large reductions in depression and guilt and substantial increases in self-esteem. White and ethnic minority women benefited equally from CTT-BW. Similar treatment outcomes were obtained by male and female therapists and by therapists with different levels of education and training. Gains were maintained at 3- and 6-month follow-ups. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
Birch Cheryl D.; Stewart Sherry H.; Wall Anne-Marie; McKee Sherry A.; Eisnor Shondalee J.; Theakston Jennifer A. 《Canadian Metallurgical Quarterly》2004,18(3):231
This study investigated whether exposure to musical mood induction procedures (MMIP) differentially increases the strength of specific alcohol expectancies for coping motivated (CM) versus enhancement motivated (EM) drinkers. Participants were 86 undergraduates who had elevated scores on either the CM or EM subscale of the Drinking Motives Questionnaire (M. L. Cooper, 1994). Participants were randomly assigned to either a positive or negative mood condition. The Alcohol Craving Questionnaire (E. G. Singleton, S. T. Tiffany, & J. E. Henningfield, 1994) was administered at baseline and after MMIP to assess phasic changes in alcohol expectancy strength. Consistent with hypotheses, only CM drinkers in the negative mood condition reported increased relief expectancies, and only EM drinkers in the positive mood condition reported increased reward expectancies. Theoretical and clinical implications are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Relapse is a central problem in smoking treatment. Data collected at the time of relapse episodes indicate that stress and negative affect (NA) promote relapse, but retrospective data are potentially biased. The authors performed a prospective analysis of stress and NA prior to initial lapses in smokers (N = 215). Day-to-day changes in stress (daily negative and positive events and Perceived Stress Scale scores) and NA (multiple momentary affect ratings) did not predict lapse risk on the following day. However, within the lapse day itself, NA was already significantly increasing hours before lapses, but only for episodes attributed to stress or bad mood. Thus, rapid increases in NA, but not slow-changing shifts in stress and NA, were associated with relapse. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Laurent Jeff; Catanzaro Salvatore J.; Joiner Thomas E. Jr. 《Canadian Metallurgical Quarterly》2004,16(4):373
Considerable empirical support exists for the positive affect and negative affect components of the tripartite model of anxiety and depression proposed by L. A. Clark and D. Watson (1991); however, less attention has been paid to the physiological hyperarousal component of the model. The development of the Physiological Hyperarousal Scale for Children (PH-C; J. Laurent, S. J. Catanzaro, & T. E. Joiner Jr., 1995) is described. The psychometric properties of items are examined using students in Grades 6-12 (N = 398). Initial scale validation includes a joint factor analysis with the Positive and Negative Affect Scale for Children (PANAS-C; J. Laurent et al., 1999; J. Laurent, K. Potter, & S. J. Catanzaro, 1994). The relationship between the PH-C and existing measures that tap related constructs is examined. Together, the PH-C and PANAS-C provide a means to assess tripartite model constructs useful in differentiating anxiety and depression. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献