Effect of microwave‐assisted extraction on the release of polyphenols from ginger (Zingiber officinale)

The significance of different variables viz. temperature, time and solvent at constant power in microwave‐assisted extraction (MAE) process of ginger was studied and compared with conventional method. Aqueous ethanol (50%) provided higher yields of extract as well as the highest release of total polyphenols (TPP) than alcoholic solvents. The reason could be the high dielectric constant of aqueous ethanol as compared to alcohols. Microwave heating being a volumetric process, an exposure time of 1 min was found to be sufficient. The better penetration of microwaves and greater solubility at higher temperature resulted in higher yield of TPP and [6]‐gingerol. The resultant extract showed higher radical scavenging activity (RSA) values. Thus, MAE allowed higher recoveries compared to conventional extraction process, with improvement in the quantity and quality of extract in very short period of time.     

REFLICS: Real-time flow imaging and classification system

An accurate analysis of a large dynamic system like our oceans requires spatially fine and temporally matched data collection methods. Current methods to estimate fish stock size from pelagic (marine) fish egg abundance by using ships to take point samples of fish eggs have large margins of error due to spatial and temporal undersampling. The real-time flow imaging and classification system (REFLICS) enhances fish egg sampling by obtaining continuous, accurate information on fish egg abundance as the ship cruises along in the area of interest. REFLICS images the dynamic flow with a progressive-scan area camera (60 frames/s) and a synchronized strobe in backlighting configuration. Digitization and processing occur on a dual-processor Pentium II PC and a pipeline-based image-processing board. REFLICS uses a segmentation algorithm to locate fish-egg-like objects in the image and then a classifier to determine fish egg, species, and development stage (age). We present an integrated system design of REFLICS and performance results. REFLICS can perform in real time (60 Hz), classify fish eggs with low false negative rates on real data collected from a cruise, and work in harsh conditions aboard ships at sea. REFLICS enables cost-effective, real-time assessment of pelagic fish eggs for research and management. Received: 12 April 2000 / Accepted: 6 July 2000     

Developments in low-cost housing

The co-ordinator of working group W63 shows, in this abridged version of his paper, how several countries have brought a degree of pragmatism to their innovations, which take account of the realities of their situation in terms of material and manpower resources and the level of technology appropriate to their needs.     

A comparative evaluation of harmonic reduction techniques inthree-phase utility interface of power electronic loads

Power electronic loads inject harmonic currents into the utility system. This paper presents a comparative evaluation of harmonic reduction techniques which satisfy the current harmonic limits specified by the IEEE Standard 519, and at the same time provide a regulated DC output voltage. The techniques considered include active and hybrid filters, and various current waveshaping approaches for a three-phase utility interface. These techniques are compared in terms of their complexity (number of switches) and their component ratings. Based on the application requirements and the cost of active and passive components, this paper enables the estimation of the minimum cost topology     

Generalized Multiple Baseline Stereo and Direct Virtual View Synthesis Using Range-Space Search, Match, and Render

A new range-space approach is described for synergistic resolution of both stereovision and reflectance (visual) modeling problems simultaneously. This synergistic approach can be applied to arbitrary camera arrangements with different intrinsic and extrinsic parameters, image types, image resolutions, and image number. These images are analyzed in a step-wise manner to extract 3-D range measurements and also to render a customized perspective view. The entire process is fully automatic. An extensive and detailed experimental validation phase supports the basic feasibility and generality of the Range-Space Approach.     

The Antecedents of Community-Oriented Internet Use: Community Participation and Community Satisfaction

The linkage between the Internet and the offline community has been the subject of considerable research in the last decade. Scholars have been particularly interested in the effects of the Internet on offline community, and the relationship between Internet use and community participation. Based on the social shaping of technology and channel complementarity theories, this study proposes that community participation will be positively related to community-based Internet use. In addition, it posits that satisfaction with the community will emerge as a positive predictor of community-based Internet use. A regression analysis of data gathered by the Pew Center for the People and the Press demonstrates that community satisfaction and community participation explain variance in community-based Internet use beyond that explained by demographic variables.     

Development of an ergonomic evaluation facility for Indian tractors

The design of tractors manufactured in low-income countries like India has not changed much in the past two decades, especially from an ergonomic point of view. Moreover, in these countries tractors are used for transportation purposes in addition to farming operations. Therefore, the design criteria for these tractors need to be different from those in high-income countries. This paper describes the development of an ergonomic facility for improvement of tractor design. An ergonomic evaluation facility has been developed consisting of a work place envelope for the Indian population, a layout measuring device and an ergonomic rig. This facility can be used for comparative evaluation of the display and control layouts of different tractors in order to develop an optimum layout. The ergonomic rig has the facility to simulate the improved layout for subjective evaluation.     

TV shearography: quantitative measurement of shear-magnitude fields by use of digital speckle photography

Digital speckle photography combined with TV shearography is developed for precise measurement of the magnitude of the shear field in a linear shear configuration. As an application the method is implemented to determine the slope-change variations of a three-dimensional object with TV shearography in which the shear magnitude is obtained with the digital speckle photography technique.