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101.
Damping Effect on Waves Propagating Past a Submerged Horizontal Plate and a Vertical Porous Wall 总被引:1,自引:0,他引:1
A set of analytical solutions for waves propagating past a combined submerged horizontal plate and vertical porous wall breakwater system is presented. The wave damping effect caused by the horizontal plate induced flow constriction is considered in the analysis. The velocity potentials in each fluid domain are derived based on the linear wave theory and the unknown coefficients are determined from the matching conditions using three sets of orthogonal eigenfunctions. Reflection and transmission coefficients are presented to evaluate the performance of the breakwater system. The analytical solutions in terms of the reflection and transmission coefficients as well as the hydrodynamic force on the vertical porous wall are found in good agreement with published laboratory measurements. In comparison with the solutions without taking into account the wave damping effect, the present analytical solutions significantly improve the accuracy of the wave predictions, especially for the reflected waves. 相似文献
102.
Patricia R. Pfeiffer Angela R. Bielefeldt Tissa Illangasekare Bruce Henry 《Canadian Metallurgical Quarterly》2005,131(10):1447-1452
Laboratory experiments were conducted to investigate the abiotic interactions of soybean oil (SoyOil) and chlorinated ethene (CE) nonaqueous phase liquids (NAPLs). The mixed NAPL density and interfacial tension behaved ideally, as predicted by the volume ratio. The mixed NAPL viscosity increased exponentially from that of the pure CE to that of pure SoyOil as the volume fraction increased. The measured contact angle was highly variable and was unpredictable as a function of the volume composition of the mixed NAPL. The physical property effects indicate that the mobilization of residual CE NAPLs because of SoyOil injection is unlikely. Equilibrium dissolution of CEs from the NAPL mixtures behaved linearly as a function of the mole fraction. Dissolved SoyOil in simulated groundwater enhanced the dissolution of trichloroethene (TCE) during flow tests, increasing the effluent TCE concentration from 141?to?202?mg/L. The ready intermingling of the CE dense nonaqueous phase liquids (DNAPLs) and SoyOil indicate that such interactions may be significant at sites where vegetable oil is injected into DNAPL source areas to enhance in situ anaerobic bioremediation. 相似文献
103.
Components of the therapeutic process have been shown to be moderately strong predictors of change in patients' global interpersonal functioning during therapy. The authors sought to extend this research by examining how the therapeutic process in time-limited dynamic psychotherapy related to change in patients' perceptions of a specific relationship as rated by the Structural Analysis of Social Behavior. Results showed that ratings of therapist warmth at Session 3 predicted increased warmth and decreased hostility in patient behavior at posttreatment. Therapist warmth at Session 16 was predictive of a decrease in submissive behavior by patients toward their significant other. The importance of the association between the therapeutic process and patients' important interpersonal relationships is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
Floris Bex Henry Prakken Chris Reed Douglas Walton 《Artificial Intelligence and Law》2003,11(2-3):125-165
This paper studies the modelling of legal reasoning about evidence within general theories of defeasible reasoning and argumentation. In particular, Wigmore's method for charting evidence and its use by modern legal evidence scholars is studied in order to give a formal underpinning in terms of logics for defeasible argumentation. Two notions turn out to be crucial, viz. argumentation schemes and empirical generalisations. 相似文献
105.
In 1984, computing firms saw integrated voice/data terminals (IVDTs) as the solution to the proliferation of new forms of executive communication. The Sydis VoiceStation was hailed as the best of this new class of office machine but, like all IVDTs, it failed. Sydis succumbed to "integration stress," one danger of product development driven by the urge to integrate traditionally discrete functions. Sydis also failed from poor integration of financial and market actors. 相似文献
106.
The effect of varying the aluminium oxide content on the nucleation and crystallization behaviour of barium containing glasses based on 8SiO2·YAl2O34MgO2MgF2BaO was investigated in order to develop novel, high strength, machinable glass-ceramics. Nine glasses were synthesized and characterized by Differential Scanning Calorimetry (DSC) Combined Differential Thermal Analysis Thermal Gravimetric Analysis (DTA/TGA), X-ray diffraction (XRD) and dilatometry. The glass transition temperature (T g) and first peak crystallization temperature (Tp1) reduced with reducing alumina content. Glasses with Y > 1.5 exhibited a second peak crystallization temperature (Tp2). Tp1 was shown to correspond to the crystallization of barium fluorphlogopite (BaSi6Al2Mg6F2O19) and Tp2 to the crystallization of cordierite (Mg2Al2Si5O18). The thermal expansion coefficient (TEC) was insensitive to alumina content. All the glasses exhibited an optimum nucleation temperature just above T g, which was thought to be a result of amorphous phase separation (APS). DTA/TGA showed the glasses to undergo weight loss corresponding to silicon tetrafluoride volatilization from the surface, which resulted in a fluorphlogopite deficient surface layer. 相似文献
107.
Ferry Dharmawan Rodney S. Thomson Henry Li Israel Herszberg Evan Gellert 《Composite Structures》2004,66(1-4):181-187
The structural integrity and damage tolerance of typical composite T-joints found in ships constructed from glass fibre reinforced plastic was the subject of this investigation. The effect of the geometry of the T-joint on the strain distribution was investigated using finite element (FE) analysis. The results, reported in this paper, showed that the critical strains were significantly affected by the joint geometry. Results of the FE analysis conducted to investigate the effect of disbonds between the filler and overlaminate are also reported. This showed that particular defects led to large changes in the strains in the T-joint structure, which would encourage disbond progression. The FE model was validated by mechanical tests on a representative T-joint, instrumented with surface strain gauges and displacement transducers, into which a range of defects was progressively introduced. 相似文献
108.
Marsh Elizabeth J.; Dolan Patrick O.; Balota David A.; Roediger Henry L. 《Canadian Metallurgical Quarterly》2004,19(1):134
In 3 experiments, the authors examined part-set cuing effects in younger and older adults. Participants heard lists of category exemplars and later recalled them. Recall was uncued or cued with a subset of studied items. In Experiment 1, participants were cued with some of the category names, and they remembered fewer never-cued categories than a free-recall condition. In Experiment 2, a similar effect was observed for category exemplar cues. There was also an age difference: By some measures, a small number of cues impaired older adults more than younger. Experiment 3 replicated this result and found that older adults were disproportionately slow in the presence of cues. Across experiments, older adults showed robust part-set cuing effects, and sometimes, they were disproportionately impaired by cues. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
109.
110.
当证监会第二天就找上门来希望合作之前,中科院软件学院院长潘辛平博士并没有预料到他写的“建设金融科技中心”的提案会有这么强的反馈。潘辛平说:“他们希望我们能够在科研、测试、认证和监管方面和我们全面合作,并且提供足够的人才和项目。”事实上,从担任中科院软件学院院长的那一天起,在中国金融科技界享有盛誉的潘辛平就明确了自己的工程化人才教育模式。他认为,工程教育应该比工学教育更加关注流程化、标准化、团队作 相似文献