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71.
I. Aidos N. Kreb M. Boonman J.B. Luten R.M. Boom A. Van Der Padt 《Journal of food science》2003,68(2):581-586
ABSTRACT: A pilot plant used for upgrading herring byproducts into fish oil was analyzed on its operational efficiency and product quality. The temperature of the heat exchanger and the speeds of the pump and the 3-phase decanter were varied according to a 23 fractional factorial design. The initial amount of oxidation products present in the crude oil, its storage stability, and the yields from the different obtained products were determined. Multivariate data analysis of the advanced screening stage showed that T had neither influence on the quality nor on the yield in contrast to D and MP (P < 0.05). Process optimization results showed that the quality of the oil was influenced by an interaction effect between the speed of the MP and the D. Oils processed with the highest MP speed were the most stable during storage. 相似文献
72.
Danil Van Nieuwenhove Ward van der Tempel Riemer Grootjans Johan Stiens Maarten Kuijk 《IEEE sensors journal》2007,7(3):317-318
A current assisted photonic demodulator for use as a pixel in a 3-D time-of-flight imager shows nearly 100% static demodulator contrast and is operable beyond 30 MHz. An integrated tunable sensitivity control is also presented for increasing the distance measurement range and avoiding unwanted saturation during integration periods. This is achieved by application of a voltage on a dedicated drain tap showing a quenching of sensor sensitivity to below 1% 相似文献
73.
Solar cells are the most commonly used devices in customer products to achieve power autonomy. This paper discusses a complementary approach to provide power autonomy to devices on a human body, i.e., thermoelectric conversion of human heat. In indoor applications, thermoelectric converters on the skin can provide more power per square centimeter than solar cells, particularly in adverse illumination conditions. Moreover, they work day and night. The first sensor nodes powered by human heat have been demonstrated and tested on people in 2004-2005. They used the state-of-the-art 100-muW watch-size thermoelectric wrist generators fabricated at IMEC and based on custom-design small-size BiTe thermopiles. The sensor node is completed with a power conditioning module, a microcontroller, and a wireless transceiver mounted on a watchstrap 相似文献
74.
Recent years have witnessed major governmental initiatives regarding critical infrastructure protection (CIP). During that same time, critical infrastructures (CIs) have undergone massive institutional restructuring under the headings of privatization, deregulation and liberalization. Little research has gone into understanding the interactions between these two developments. In this article, we outline the consequences of institutional restructuring for the changing ways in which CIs ensure the reliability and security of their networks and services. Neither Normal Accident Theory nor High‐Reliability Theory can account for reliability under these conditions. We then investigate the implications of these findings for CIP. 相似文献
75.
A comprehensive model for the recrystallization kinetics is proposed which incorporates both microstructure and the textural
components in the deformed state. The model is based on the single-grain approach proposed previously. The influence of the
as-deformed grain orientation, which affects the stored energy via subgrain size and sub-boundary misorientation, is taken into account. The effects of the deformed grain geometry, the nucleation-site
density, and the initial grain size prior to deformation on the recrystallization kinetics are assessed. The model is applied
to the recrystallization kinetics of a cold-rolled AA1050 alloy. 相似文献
76.
77.
Pin&Play: the surface as network medium 总被引:2,自引:0,他引:2
Van Laerhoven K. Villar N. Schmidt A. Gellersen H.-W. Hakansson M. Holmquist L.E. 《Communications Magazine, IEEE》2003,41(4):90-95
Integrating appliances in the home through a wired network often proves to be impractical: routing cables is usually difficult, changing the network structure afterward even more so, and portable devices can only be connected at fixed connection points. Wireless networks are not the answer either: batteries have to be regularly replaced or changed, and what they add to the device's size and weight might be disproportionate for smaller appliances. In Pin&Play, we explore a design space in between typical wired and wireless networks, investigating the use of surfaces to network objects that are attached to it. This article gives an overview of the network model, and describes functioning prototypes that were built as a proof of concept. 相似文献
78.
79.
RC Smith JS Lyles JA Mettler AA Marshall LF Van Egeren BE Stoffelmayr GG Osborn V Shebroe 《Canadian Metallurgical Quarterly》1995,70(8):729-732
PURPOSE: To use a controlled, randomized design to assess the effect on patient satisfaction of an intensive psychosocial training program for residents. METHOD: Twenty-six first-year residents, in two internal medicine and family practice community-based programs affiliated with the Michigan State University College of Human Medicine, were randomly assigned during 1991 and 1992 to a control group or a one-month intensive training program. Experiential teaching focused on many psychosocial skills required in primary care. A 29-item questionnaire administered before and after the residents' training evaluated their patients' satisfaction regarding patient disclosure, physician empathy, confidence in physician, general satisfaction, and comparison of the physician with other physicians. Analyses of covariance with groups and gender as factors and pre-training patient satisfaction scores as the covariate evaluated the effect of the training. RESULTS: The patients of the trained residents expressed more confidence in their physicians (p = .01) and more general satisfaction (p = .02) than did the patients of controls. The effect of training on patient satisfaction with patient disclosure (p < .01) and physician empathy (p < .05) was greater for female than for male residents. CONCLUSION: The intensive psychosocial training program for residents improved their patients' satisfaction. 相似文献
80.
G Franzosi E Battistel I Gagliardi W Van der Goes 《Canadian Metallurgical Quarterly》1995,43(3):508-513
A screening of microorganisms producing glutaryl-7ADCA acylase, an enzyme able to hydrolyse glutaric acid selectively from glutaryl-3-deacetoxy-7-aminocephalosporanic acid (glutaryl-7ADCA), has been carried out in soil samples. Five microorganisms expressing acylase activity were isolated and classified as Bacillus cereus, Achromobacter xylosooxidans, Bacillus sp., Pseudomonas sp. and Pseudomonas paucimobilis. The screening was carried out by preparing enrichment cultures containing glutaryl-7-ADCA or cephalosporin C as the selective carbon source. Four model compounds (adipoyl-, glutamyl- and glutaryl-p-nitroanilide and glutarylcoumarin), mimicking the glutaryl-7ADCA beta-lactam moiety, were synthesized as substrates suitable for the rapid screening of the microorganisms (2500) isolated from the enrichment cultures. A total of 300 strains were active on the model substrates and only 5 displayed acylase activity on glutaryl-7ADCA. The fermentation parameters, such as pH and inducer concentration, for the optimal acylase expression and acylase specificity towards the model substrates were different for each strain. 相似文献