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41.
An analytical computer model of an ink jet printing system was created. Based upon the values of 13 input parameters, the program delivers predictions of the forces acting on individual drops and their resulting dynamic behavior. Predictions of drop displacements and flight times were used to infer drop pattern appearance resulting from a given input signal. The computer model was based upon theoretical work plus extensive empirical measurements. Drop behavior was predicted with modest accuracy. An improved understanding of ink jet printing systems and numerous recommendations for their use were also derived in this study.  相似文献   
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Structural health monitoring (SHM) is a promising field with widespread application in civil engineering. Structural health monitoring has the potential to make structures safer by observing both long-term structural changes and immediate postdisaster damage. However, the many SHM studies in the literature apply different monitoring methods to different structures, making side-by-side comparison of the methods difficult. This paper details the first phase in a benchmark SHM problem organized under the auspices of the IASC–ASCE Structural Health Monitoring Task Group. The scale-model structure adopted for use in this benchmark problem is described. Then, two analytical models based on the structure—one a 12 degree of freedom (DOF) shear-building model, the other a 120-DOF model, both finite element based—are given. The damage patterns to be identified are listed as well as the types and number of sensors, magnitude of sensor noise, and so forth. MATLAB computer codes to generate the response data for the various cases are explained. The codes, as well as details of the ongoing Task Group activities, are available on the Task Group web site at 〈http://wusceel.cive.wustl.edu/asce.shm/〉.  相似文献   
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Observers consciously prefer Mondrian's paintings in their original orientation compared with a rotated position—the “oblique effect” (Latto, Brain, & Kelly, 2000). However, this finding's premise, that all vertical–horizontal orientations of the thick black lines in Mondrian's oeuvre are preferred, overlooks the fact that the overall balance of these images is also altered when they are reoriented. Thus, balance may regulate the oblique effect, which might influence conscious aesthetic preferences. To address this issue, we explore Hess's (1965, 1972) claim that observers will unconsciously increase their pupil diameter to pleasing images and constrict it to unpleasant images. We overcame Hess's methodological limitation of not keeping his images' luminances and contrast constant across conditions by presenting eight Mondrian paintings (1921–1944) to 30 observers on a CRT for 20 s each in either their original or seven rotated positions. Simultaneously, we measured their pupil size while asking them to report how (dis)pleasing they found each image. We found both evidence for the oblique effect (where image rotation hampers preference) and a correlation between this consciously reported aesthetic preference and unconsciously derived pupil size. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Various reaction variables in the hydrogen peroxide oxidation of starch in the presence of UV light have been investigated. Higher carboxyl and carbonyl contents of oxystarches were obtained under acidic than under alkaline conditions. Extent of oxidation was found to increase with time. Increasing the concentration of hydrogen peroxide results in an increase in the carboxyl and carbonyl contents. Apparently, air has no effect on the degree of oxidation whereas, oxygen seems to accelerate it.  相似文献   
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A task as large as influencing the global economy requires that some thought be given to suitable strategies. Recent work in the science of cybernetics has identified four separate strategies for regulating complex systems composed of thinking participants. By using these strategies as a foundation, this paper reviews the history of the global economy, summarizes current concerns, and then identifies several possible courses of action.  相似文献   
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