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1.
Traditional West African pearl millet couscous products are popular; however, their preparation is laborious, time-consuming and energy-demanding, involving agglomeration, steaming, drying and sieving steps. In this study, a process was developed to produce millet couscous using a high pressure, high temperature and low-cost single-screw extruder. The innovation was to directly process the cooked low-moisture extrudate to a couscous product by drying and milling to the appropriate particle size (ranging between 1 and 2 mm). Throughput for the traditional process as prepared for commercial sale is 50 kg per day, but with the same amount of labour, the extrusion process yields ~350 kg per day. A consumer sensory study held in Niamey (Niger) showed that the extruded millet couscous was comparable to traditional couscous, though this was dependent on selection of the proper millet variety. This novel extrusion process could stimulate small- to medium-scale manufacturing of couscous and couscous-type products in West Africa.  相似文献   
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This paper presents an analysis and design procedure for a buoyant cable array antenna used for satellite communications. The towed multi-element array is susceptible to washovers and fluctuations due to the ocean wave interaction with the floating hose where the elements are housed. A model of system performance for coherent multi-element combining is presented based on the dropouts and fades of the individual elements. The array design, including the number and spacing of elements, is shown to be highly dependent on the individual element exposure characteristics and the degree of correlation of the fades between channels. The joint statistics of the array are analyzed using a binary conditional element exposure model and a first-order Markov interelement correlation model. Using this analysis, a family of array designs meeting the communications requirements is produced.  相似文献   
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A series of studies of top European and other firms has revealed patterns of design management associated with commercial success. Firms that invest resources and professional expertise in product and industrial design in traditional and new industries have been commercially more successful than firms that pay less attention to these aspects of design. As an industry matures there is a shift in emphasis from design associated with technological innovation, to designs supporting technical improvements, and then to supporting user needs, fashion and product variants. These issues are illustrated through the history of the evolution of the bicycle.  相似文献   
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In this paper we analyse issues associated with overloads in tandem switching systems in Common Channel Signalling (CCS) networks. In particular, we examine the need for, and effectiveness of, Automatic Congestion Control (ACC), a CCS mechanism which allows a congested switching system to inform adjacent CCS nodes of its level of overload, and subsequently controls the rate at which traffic is sent to the congested node. We demonstrate the critical need for end-offices and tandem switching systems to implement some form of ACC if network performance is to be maintained during congestion, especially in tandem exchanges. In addition, we find that the presently defined ACC should be expanded to allow more levels of congestion to be reported to adjacent nodes, so that a more effective, finer grained control is produced.  相似文献   
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A total of 438 manufacturing firms reported their business relocation activity, their overall attitude toward the business climate in Michigan, and their assessment of 34 business climate dimensions. Using a lens model paradigm, we explored reasons for a lack of relation between actual relocation decisions and overall business climate attitudes. Location decisions were most highly correlated with distance and labor considerations, whereas overall business climate was most highly correlated with tax considerations, and secondarily correlated with labor problems. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Much of the writing on the psychological autopsy is reviewed. Several writers' opinions about what should be included in a comprehensive behavioral analysis conducted after an individual's death are compiled in an Appendix. Several additional and new areas to be covered in a psychological autopsy are included. The primary emphasis is on the provision of a practical guide for the working professional. Twenty-four separate factors, ranging from reconstruction of events that occurred before the death to the deceased's family death history, are presented. Some legal considerations are examined briefly in order to acquaint the professional with the significant impact that the results can have on family benefits and criminal prosecution. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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700 undergraduates were tested in 3 experiments on original or rewritten versions of 52 instructional texts about Army job tasks, general science, philosophy, and history. Five experts had rewritten various sets of the texts and stated hypotheses about the efficacious features of their revisions. We tested their hypotheses and several others. Recall and recognition tests were given immediately and after a 24-hr delay. Results showed that revisions made by 3 of the 5 experts improved retention of text information. The kind and number of revisions and improvements varied across the text sets. Most expert hypotheses were not supported, and they made many revisions they were declaratively unaware of. Some of our hypotheses about the revision features were supported, but different features were effective for different sets of texts. It was concluded that some experts have effective knowledge about improving instructional text, but it exists primarily in procedural form. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Results of a simulation study of the economics of frequency of rescheduling Material Requirements Planning (MRP) systems are presented for a single-product, two-stage system in which demand is uncertain. The results indicate that for systems with moderate demand uncertainty, frequent rescheduling to maintain customer service may be uneconomical when compared with the alternative of more stable schedules in conjunction with safety stock. This result arises primarily because the cost of “emergency” production setups which occur when rescheduling is frequent exceeds the cost of safety stock required to “protect” stable schedules.  相似文献   
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