On the application of vibratory disk feeders for silos

Originally vibratory disk-feeders and-reclaimers were designed with rather small diameters. They were mainly applied in chemical process plants, and were mostly flush mounted underneath bins of modest size, say up to 1 m diameter. Over the past decades they have been increasingly used for bins of much larger diameter, some via a hopper and some not. The latter may cause an unfortunate combination of the most important parameters, leading to malfunctioning and even to feeder jam. This work shows that basically vibratory disk feeders should be installed via a hopper, which for practical reasons becomes feasible above diameters of approximately 0.8 m, depending on the material to be reclaimed and the required mass flow. Feeders of considerable size, up to 2.5 m, may very well operate satisfactorily when properly mounted underneath a hopper. Nonfunctioning of vibratory disk feeders is mostly caused by a combination of too bad flowability of the bulk material to be reclaimed; too high a feeder load and wrong silo fill procedures and feeder power-up procedures.     

Solar panels BPX47A for terrestrial applications

Solar panels are used for direct conversion of solar radiation into electrical energy. Based on ten years experience in space and terrestrial projects the BPX47A has been developed to meet stringent requirements imposed by humid, arid, tropical, subtropical, continental and arctic climates. This paper describes operation of the solar panel in combination with storage batteries, design considerations, solar radiation on the earth's surface, optimum design of a power station and an example of a realized project.     

Effective coordination in the software process - historical perspectives and future directions

A critical factor in delivering quality software products is the quality of the software process. Software development is characterized by its multi-party activity (MPA), and a major challenge in managing the software process is the coordination of its constituent activities, resources and people. In this paper, we review approaches and techniques for managing multi-party activity in the software process in terms of their originating domain and the coordination features they address. Malone and Crowston's framework of coordination dependencies is adopted to consider common dependencies between activities and to classify the different approaches that have been taken to their management in software engineering. Some observations are made regarding strategies for achieving effective coordination and on areas for further investigation.     

Principaux facteurs d'immunite et de corrosion du nickel dans un milieu bacterien

The corrosion of nickel has been studied in fresh and sea-water, in the presence of 17 bacteria of various properties and with four different nutrients. The metal is protected by a bacterium living normally. A small amount of corrosion can occur with living bacteria consuming a small amount of oxygen. Cases of severe corrosion are observed when the bacteria disappear. Bacterial death can be caused by acid pH, high redox potential and dissolved nickel ions.     

In vitro Antimicrobial Activity of Ozonized Theobroma Oil Against Candida albicans

In this paper, a study of antimicrobial activity of ozonized theobroma oil against Candida albicans was carried out. Minimum inhibitory concentration and minimum fungicide concentration from ozonized theobroma oil for several peroxides indexes were determined. Mortality kinetics for peroxide index of 1200 mmol-eq/kg was carried out. Effect of contact time, peroxide index and ozonized theobroma oil concentration on Candida albicans mortality was studied. Under the conditions studied, minimum inhibitory concentration and minimum fungicide concentration values between 5 and 3.75 mg/mL and 11.58 and 5.78 mg/mL were obtained for peroxides indexes of 1002 and 1200 mmol-eq/kg of sample, respectively.

Microorganism inactivation follows first order kinetics. An optimal concentration value of 93.75 mg/mL was obtained. Further increases of ozonized theobroma oil concentration did not exert any influence on mortality. Under the variables ranges studied all parameters have a significant effect on the mortality of Candida albicans, contact time being the most important factor.     

Rotational particle separator: A new method for separating fine particles and mists from gases

An account is given of the patented technique of the rotational particle separator for separating solid and liquid particles of diameter 0.1 μm and larger from gases. Attention is focused on the working principle, fluid mechanical constraints, particle design, separation performance, power consumption, dimensions, filter cleaning and costs. Furthermore, an overview is given of current developments to introduce this technique in industrial dust removal, in electricity generation and in the consumer goods market. The article concludes with a summary of the feature which distinguish this technique from existing filtering methods.     

Axios river basin water quality management

This paper presents a consistent methodology to analyze the water quality management of a river basin. Mathematical modelling techniques are used to establish the water quality characteristics of the study area and to assess the effects of alternative management strategies in a quantitative way.The Axios river basin in Northern Greece is used as a target area to demonstrate the capabilities of the methodology and the computational framework. The study provides a thorough examination of the water use in the river basin, the associated water quality standards, external factors influencing the water quality and alternative measures. Finally, a quantitative comparison of management strategies is given.     

International trends in research and technology development

The way in which research and technology development in building and construction is conducted in most industrialized countries is changing dramatically. Major changes include a reduced dependence on government support for R&D, the development of a partnership between the construction industry and the research community, internationalization of construction research as a market, the subsequent impact for national research programmes, increased international collaboration between national research organizations, and the impact of electronic communication. The changing role of CIB is discussed as positive response to these challenges, which include the changing composition of CIB's membership (from East Asia and North America), increased participation by industry, more focused CIB programmes which are closely aligned to industry's priorities, and new ways of creating international teams and working methods through the use of electronic participation. La facon de conduire les recherches ainsi que la mise au point des techniques du batiment et de la construction dans la plupart des pays industrialises est en train de changer radicalement. Les principaux changements sont: une moindre dependance vis-a-vis des aides en R&D de l'Etat, l'institution d'un partenariat entre l'industrie de la construction et le monde de la recherche, l'internationalisation du marche des recherches pour la construction, un developpement de la collaboration internationale entre les instituts de recherche nationaux et l'impact des communications electroniques. Les nouvelles missions due CIB s'analysent comme une reaction positive face a ces defis et concernent la modification de la composition des membres du CIB (originaires de l'est de l'Asie et de l'Amerique du Nord), une participation accrue de l'industrie, des programmes du CIB mieux centres et plus proches des preoccupations de l'industrie, de nouvelles methodes de travail et de constitution d'equipes internationales gr^ ace aux outils de communications electroniques.