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991.
In this case study the introduction of computer-aided design (CAD) in an engineering company was analyzed. The process of change as well as repercussions of the new technology on work organization and communication patterns within the company were studied. The designers has received the new technology favorably and were even impatient about the pace of change. As the development of the system was limited to a small group close to the design management, the introduction had less than desirable effects on the work situation of the designers and on the cooperation with other functions that was envisaged in the planned CAD/CAM step. The study confirms that CAD, as such, will have little effect on a bureaucratic organization unless such a change is included as an explicit objective. For a full utilization of any new technology a joint forum for outlining a strategy is needed  相似文献   
992.
Bovine alpha-lactalbumin and beta-lactoglobulin concentrations were determined by radial immunodiffusion in 354 milk samples from uninfected and 98 samples from infected quarters from 42 Holstein-Friesian cows taken at 30, 150, and 270 days of lactation. alpha-Lactalbumin and beta-lactoglobulin concentrations were not affected by quarter location. The alpha-lactalbumin decreased at the end of lactation and in samples collected beyond second lactation. The beta-lactoglobulin concentration increased with stage of lactation. There was a positive correlation between alpha-lactalbumin and beta lactoglobulin (r = .12). Milk from uninfected quarters had mean alpha-lactalbumin and beta-lactoglobulin concentrations of 1.47 and 4.6 mg/ml, respectively. Milk from quarters infected by major pathogens or Corynebacterium bovis had less alpha-lactalbumin. Milk from quarters infected by minor pathogens had less beta-lactoglobulin. There was a negative correlation between alpha-lactalbumin concentration and somatic cell count (r = .31), which was amplified by infection status of quarters. No correlation was noted between somatic cell count and beta-lactoglobulin concentration when considered over the whole sampling period, but the correlation became negative in quarters infected by major pathogens.  相似文献   
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994.
The StoryGrid project undertook studying the role new interface technologies might play in education, particularly at the high school level. Unfortunately, technology often seizes center stage in high school classrooms; i.e., it becomes the topic of instruction. We believe that learning about technology would be most successful when technology is not the topic, but simply a tool used during instruction. StoryGrid, therefore, was designed to support and to enhance existing narrative activity in classrooms by adhering to the following goals: trigger reflection and interpretation, accommodate individual expression and encourage student discourse.  相似文献   
995.
The Uniform Covering by Probabilistic Rejection (UCPR) algorithm was used, in conjunction with the Soil and Water Assessment Tool (SWAT) model, to identify P loads from point source and nonpoint source polluters in the upper Etowah River basin (UERB) in Georgia. The key findings of the research are as follows. The mean absolute error was preferred over the root mean square error as a search criterion for the UCPR algorithm when water quality observations are scarce. The undocumented P load from point sources in the UERB was consistently estimated as about 43 kg/d by the proposed method; but the method was not able to identify the broiler litter application rate to the poultry/beef operation pastures. Point sources (both documented and undocumented), poultry/beef operation pastures, and forests are the three major contributors of P. During 1992-1996, on average they accounted for 36.4, 31.7, and 17.2% of P load from the UERB, respectively.  相似文献   
996.
The effect of the coordination groups of boron, aluminum, and silicon on the acid-base properties of the glass mass and the change in the redox state of copper in boron-containing melts are studied. Indicators are proposed for evaluating the redox potential of the glass mass. The acid-base properties of commercial alkali-alumoborosilicate glasses are compared using these indicators. __________ Translated from Steklo i Keramika, No. 7, pp. 3–7, July, 2007.  相似文献   
997.
We study the nonlinear propagation of light in optical fibers in the strong nonlinearity limit. In this limit, the transverse guiding properties are altered and cannot be decoupled from the longitudinal part of the wave equation. We consider a refractive index profile with no bound modes at low intensities and show that stable self-guiding occurs at a critical intensity. This critical intensity is a property of the guide and can be made much lower than the threshold for unstable self-focusing. We consider a particular design for which self-guiding occurs at three orders of magnitude lower than the self-focusing threshold.  相似文献   
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