RACIAL COMPOSITION AND NEIGHBORHOOD EVALUATION

While the negative association between racial composition and neighborhood evaluation for white residents is fairly well established, there is less consensus on what are the precise mechanisms which produce this relationship. This paper examines three possible mechanisms in this regard: status loss, perceived decline in the quality of neighborhood services, and fears about personal safety. A survey of nine neighborhoods with different racial mixes finds evidence for the direct effect of racial composition on white residents' evaluations through status loss and its indirect effect through fears about personal safety, but no support for the notion that the racial composition effect operates through negative perceptions of neighborhood public services. Alternatively, having larger numbers of blacks in a neighborhood has a negative effect on black residents through its association with a perception of lower quality public services: at the same time, higher numbers of blacks in a neighborhood has a positive effect on black residents' evaluations of the area, once the association between racial composition and perception of quality of services is taken into account. This positive effect operates directly and also indirectly, through its association with perceptions of greater safety. The implications of these findings for the future of integrated neighborhoods are discussed.     

The viscosity of cheese sauces with different starch systems and cheese powders

Cheese sauces were prepared by blending cheese powders, starches, skim milk powder, flavouring agents, milk and/or water to ˜24% dry matter, cooking to 98°C and simmering for ˜2 minutes. Most sauces exhibited thixotrophic behaviour as characterized by the curvilinear decreases in viscosity and shear stress with time when subjected to a constant shear rate (118s^-1). However, Colflo 67 based sauces underwent shear thinning initially and then shear thickening at shearing times >˜200 s. Increasing the total starch level from 2 to 4% resulted in sauces which had more viscous consistencies, higher susceptibility to shear thinning and higher viscosities on completion of shearing. The rheological properties of sauces were markedly influenced by serving temperature and the type of starch base used. Variation in the level of cheese solids in the cheese powder had little influence on the rheological characteristics of sauces when used at levels of <10% (w/w).     

Size distributions of clouds in real time from satellite imagery

Abstract

An instrument is proposed to gather global data on cloud size distributions. The instrument contains a broad-band visible/infrared radiometer to scan the clouds with a field of view comparable to the grid squares of circulation models, but a resolution within the field of view of approximately 100 m, adequate to resolve the fine structure of clouds. The image is digitized, discriminated to distinguish cloudy and clear pixels, and submitted to a dedicated parallel computer which calculates the size distribution of the clouds in real time. Only the size distribution is transmitted to Earth, so the data transmission rate from the satellite is low and the archival problems at the earth station are minimal. This paper examines several alternative definitions of the size distribution of clouds, and concludes that the procedure of ‘sizing by openings’ is most appropriate. It is then shown that the processing speed required by the image analyser can be achieved at realistic power levels with present day technology.     

Ultrasonic Imaging of Micro-Leaks and Seal Contamination in Flexible Food Packages by the Pulse-Echo Technique

Reliable inspection of flexible food packages for micro-leaks and product contamination in the seal area is needed to prevent spoilage and safety hazard. Nondestructive testing by the ultrasonic imaging method, Backscattered Amplitude Integral (BAI), was evaluated for use in defect detection. Channel defects (6–15 μm in diameter) and simulated food strands (20–60 μm dia) perpendicular to the sealing direction were fabricated within the seal region of both all-plastic and foil-containing retortable pouches. Results showed that 17.3-MHz pulse-echo BAI-imaging detected channel defects (9.5–15 μm) and all strand-inclusion defects in both types of package materials.     

Cell control research— current status and development trends

A critical literature review on cell controller research is presented in this paper. Different definitions of a flexible manufacturing cell and cell controller are analysed, and comprehensive cell and cell controller definitions are given. Based on the requirements for a cell control system suggested by practitioners, users and researchers, a new set of general requirements for the development of a cell control system is proposed. After many well-known cell control systems are reviewed, a general structure of a cell controller and the general architecture of the cell control system, which includes a cell controller and a sub-system for the generation and configuration of a cell controller, are suggested. The scheduling approaches used in cell control are also discussed. The tools employed for modelling the cell control logic are examined. The trends and potential research directions in cell controller development are addressed.     

Water-Holding Capacity and Textural Acceptability of Precooked, Frozen, Whole-Egg Omelets

Precooked, frozen omelets were analyzed for moisture loss, expressible moisture, shear-force, and sensory evaluation to determine water-holding capacity and- textural acceptability. Addition of 0.1% xanthan gum, application of moist heat in cooking, and cryogenic freezing with liquid carbon dioxide or nitrogen minimized moisture loss and shear force. Sodium. carboxymethylcellulose (CMC), pre-gelatinized tapioca starch and sodium tripolyphosphate additives performed satisfactorily, but omelets containing xanthan gum were consistently rated highest in sensory evaluation of several treatments, including fresh and untreated control omelets. Steaming omelets for five minutes combined with cryogenic freezing produced a desirable- omelet, requiring no additives. Steamed omelets were rated comparable to baked omelets in most sensory parameters.     

An interactive approach to computer aided facility layout

In all manufacturing and service industries the layout of facilities is an important determinant of operating efficiency and costs. Whenever the flow of materials or people is complex, computerized procedures offer the only feasible means of developing and evaluating alternative arrangements.

This paper describes an interactive approach to construction and improvement procedures which utilizes a refresh graphics terminal (IMLAC)linked to a PRIME 400 computer. Input includes projected materials flow, estimates of material handling costs, 2-D templates of machines, etc., and an initial layout which can be either existing, proposed, or constructed using the procedure INLAYT. A heuristic procedure, S-ZAKY, utilizes multi-pairwise facility exchange to develop improved layouts based upon an analysis of materials flow. The improved layout is displayed in detail alongside the initial layout at the graphics terminal together with relevant material handling costs. The user may then accept, reject or modify the improved layout using the light-pen attached to the terminal before proceeding to successive iterations until satisfied. An economic evaluation of the projected savings in material handling costs against costs of relayout may be displayed at each iteration. On completion, a fully documented record including drawings may be obtained for every stage in the. procedure.