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71.
The effect of switching individual cow Record of Performance milk samples from on-farm Babcock analytical system to centralized infrared analysis was investigated. The effects of lipolytic activity on the signals of the fat (5.73/5.58 and 3.48/3.56 microns) and protein (6.46/6.68 microns) wavelengths of filter instruments showed that lipolysis decreased the infrared fat signal and concurrently increased the protein signal. The chain length (3.48/3.56 microns) signal was unaffected by lipolysis due to the concordant movement of the reference wavelength baseline with the changes in the sample wavelength signal. Storage trials (3 d) of preserved milk samples indicated no direct relation between fat signal depression and chemically determined free fatty acid levels. Microbial growth and agitation also contributed to changes observed in samples studied under controlled conditions. Based on concurrent infrared, Babcock, and Mojonnier analyses of approximately 900 samples on d 1 and 3, there was a consistent but marginal drop in the carbonyl (5.73/5.56 microns) fat signal and an increase in the amide (6.46/6.68 microns) protein signal, but these changes were of limited significance. A study of 3-d and older samples indicated that significant levels of acid were produced, indicative of microbial growth. A comparison of Babcock results carried out on-farm, Mojonnier analyses in the laboratory, and their corresponding infrared results did not show statistically significant differences. Other than the inherent variability present in the individual cow samples, there were minor quality changes occurring under the present sample handling system due to a combination of lipolysis, microbial growth, and acid production. Refrigeration of Record of Performance samples during transport and at the central laboratory is recommended to minimize these changes.  相似文献   
72.
This article demonstrates that the Bellcore OSCA architecture can serve as a basis for the metaarchitecture for software architectures that must support interoperability among functionality that traditionally has resided in operation systems and functionality that traditionally has resided in network elements (NE) (i.e., interoperability among operations functionality and network functionality). The need for this interoperability is driven by such telephone company business needs, as the need for customers to access operations capabilities spanning operations systems and NEs, the need for new service offerings to span operations systems and NEs, the need for a flexible environment for service development, and the need to manage all corporate data as a company resource. As a result, it is becoming beneficial to apply interoperability requirements to the network functionality that interfaces with operations systems. Therefore, it is reasonable to apply the OSCA architecture to network functionality. This article applies the OSCA architecture interoperability principles of separation of concerns to current and emerging network functionality. It demonstrates that this functionality can be partitioned among the three OSCA architecture layers of corporate data, processing, and user, and that there are a number of benefits to applying the OSCA interoperability principles to network functionality.  相似文献   
73.
Periodically adjusted parabolic mirror/evacuated tube absorber combinations are evaluated using computer simulation methods. The results show that a 4–6X reflector adjusted 10–15 times per year, operating at 150°C, competes favourably in cost-effective terms with a fixed reflector CPC collector operating at 50°C. Periodically adjusted collectors are advocated for medium temperature industrial applications below 200°C.  相似文献   
74.
In this work, we investigate the radial flow structure in gas-solids downer using Euler-Euler computational fluid dynamics (CFD) models. Solids are modeled as pseudo-fluid using kinetic theory of granular flow. In addition to the mass and momentum conservation equations, transport equation for fluctuating kinetic energy of the solids (modeled as granular temperature) is solved. The main focus of this work is the systematic investigation of the most suitable closures for the various force interactions in the system of interest. Results are presented for mean solids velocity, volume fraction, granular temperature and slip velocities for various closure forms. Sensitivity of the predicted results to the choice of closure forms is presented. Finally we emphasize the idea of matching slip velocities and the trends thereof with solids fraction as the key to developing a robust CFD model which has predictive capability over a wide variety of flow conditions.  相似文献   
75.
Access to a running wheel combined with restricted feeding produced body weight loss at an equivalent rate in male and female litter-mate rats (Experiment 1). Thus, despite weighing less and running more, females were not more vulnerable to this procedure. When factors influencing weight loss were varied, no sex difference was found in adaptation to a new feeding schedule or in the effect of single versus group housing (Experiment 2). The apparent critical difference was that body weight loss increased running in males but not in females (Experiment 3). In all rats, rapid recovery of body weight occurred when food access was no longer restricted (Experiment 1), suggesting that "activity-based anorexia" is a misnomer for weight loss by rats in a running wheel. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
76.
The term “software engineering” has been in use for over twenty years. Yet, it lacks a precise, generally acceptable interpretation. This situation has made it especially difficult to define and implement educational programs in this relatively new discipline. This paper discusses the experience and results of one of the first successful graduate programs in the field, the Seattle University Master of Software Engineering (MSE) program. This program was established in 1979, and the results of its first several years of operationare reviewed in this article.  相似文献   
77.
78.
A form of nomographic chart for the solution of the modulus of rupture equation is described. The chart is direct reading and less time is required for the determination from experimental data than with most methods.  相似文献   
79.
80.
The authors correct several typographical errors, and misinterpretations in their abovementioned paper (see ibid., vol.SE-12, no.1, p.3-11, Jan. 1986).<>  相似文献   
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