BLSS: A Contribution to Future Life Support

The problem of the supply of basic life supporting ingredients was analyzed. Storage volume and launch weight of water, oxygen and food in a conventional nonregenerable life support system are directly proportional to the crew size and the length of the mission. Because of spacecraft payload limitations this requires that the carbon, or food, recycling loop, the third and final part in the life support system, be closed to further reduce logistics cost. Advanced life support systems need to be developed in which metabolic waste products are regenerated and food is produced. Biological life support systems (BLSS) satisfy the space station environmental control functions and close the food cycle. Numerous scientific space experiments were delineated, the results of which are applicable to the support of BLSS concepts. Requirements and concepts are defined and the feasibility of BLSS for space application are analyzed. The BLSS energy mass relation, and the possibilities to influence it to achieve advantages for the BLSS are determined. A program for the development of BLSS is proposed

Technology survey of computer software as applicable to the MIUS project

Existing computer software, available from either governmental or private sources, applicable to modular integrated utility system program simulation is surveyed. Several programs and subprograms are described to provide a consolidated reference, and a bibliography is included. The report covers the two broad areas of design simulation and system simulation

Waste Collection Vehicle Routing Problem: Literature Review

Waste generation is an issue which has caused wide public concern in modern societies, not only for the quantitative rise of the amount of waste generated, but also for the increasing complexity of some products and components. Waste collection is a highly relevant activity in the reverse logistics system and how to collect waste in an efficient way is an area that needs to be improved. This paper analyzes the major contribution about Waste Collection Vehicle Routing Problem (WCVRP) in literature. Based on a classification of waste collection (residential, commercial and industrial), firstly the key findings for these three types of waste collection are presented. Therefore, according to the model (Node Routing Problems and Arc Routing problems) used to represent WCVRP, different methods and techniques are analyzed in this paper to solve WCVRP. This paper attempts to serve as a roadmap of research literature produced in the field of WCVRP

Aerospace medicine and biology: A continuing bibliography with indexes, supplement 204

This bibliography lists 140 reports, articles, and other documents introduced into the NASA scientific and technical information system in February 1980

Livestock farmers' attitude towards manure separation technology as future strategy

In this paper, an ordered probit model is used to assess the factors that affect the probability of livestock farmers having plans to adopt manure separation technology in the future. A survey, based on a postal and computerized questionnaire of representative dairy and pig farms in the Netherlands was carried out in 2009. The results show that age of farmer and a variable which accounts for the interaction between size and location of the farm are important variables explaining the probability of farmers having plans to adopt manure separation technology. Furthermore, farmers who agreed that future application norms are the driving force for considering adoption of manure separation technology were more likely to consider manure separation as the right strategy for their farm. This outcome implies that farmers are considering manure separation as a strategy to survive the more stringent future application norms. Policy implications are that young farmers with bigger Dutch size unit located in manure regions where there is oversupply of manure are more likely to adopt manure separation technology in the futur

Management: A continuing bibliography with indexes

This bibliography lists 551 reports, articles, and other documents introduced into NASA scientific and technical information system in 1980

A GIS-Based Optimization Technique for Spatial Location of Municipal Waste Bins in a Developing City

Prime spatial features such as environmental constraints and indigenous transit routes which determine optimal waste bin locations in developing areas are often neglected. In this study, we illustrate a technique that includes these features to determine the optimal locations of waste bins for case study in Ilorin, Nigeria. The built-in solver for p-median problems in the Geographic information system (GIS)-based package; TransCAD v. 5.0 was used to determine the optimal locations of one to ten waste bins. This optimization technique requires less computational time and the output of ten computer runs showed that partial service coverage was obtained when p=1 to 5 while full service coverage was achieved with p≥6. Also the GIS optimized waste bin locations tend to be more accessible to waste generators than the empirical waste bin locations. Hence, this technique has the potential to improve service coverage and public satisfaction in developing areas.Keywords: Municipal solid waste; Geographic information system; waste bin; optimal location; developing city

Maintenance and Asset Life Cycle for Reliability Systems

This chapter presents tools, methods, and indicators, in order to develop a successful and modern maintenance program. These are based on reliability engineering that improves the reliability of a system or complex equipment. Frequently, the industry implements maintenance schemes, which are based on equipment’s manufacturer’s recommendations and may not apply changes throughout the asset life cycle. In this sense, several philosophies, methodologies, and standards seek to assist this process, but most of them do not take into consideration their operation characteristics, production necessity, and other factors that are regarded as being important to one’s company. This method is based on the analysis of preventive component replacements and the subsequent critical consequences. These analyses may be used as a decision-making tool for defining component replacement decisions. In this chapter, the first section introduces and justifies the importance of this topic being approached from the perspective of asset management. Next, it discusses key maintenance concepts and techniques, with the aim of establishing the foundation of a maintenance management. The purpose of the final section is to present a maintenance strategy model, and it presents the findings of the case study about model implementation at home cleaning service company

OPTIMAL MAINTENANCE PROGRAM OF A WASTE-TO-ENERGY PLANT : Case Study: wasteWOIMA®

Waste-to-energy (WtE) plant is a complex system which requires different maintenances to be reliable and available in its full functionalities. Maintenance has a crucial impact on the performance, availability and reliability of the WTE plant. The inadequacies of WTE plant lifetime maintenance may increase the production costs, and more it negatively affects the competitiveness, makes the downtime longer and the Mean-Time-Failure is bigger. The thesis focuses on the maintenance of WtE plant and it reviews the existing literature about Waste-to-Energy maintenance program and then find the best combination that better suits a Waste-to-Energy plant. This thesis has into two parts: the first part identifies the critical factors that enable high availability of Waste-to-Energy plant and the second addresses the identification of the right criteria for spare part selection. Both parts are aimed at enhancing the availability of Waste-to-Energy plant. A survey was sent to Waste-to-Energy professionals to collect data and compare that data to the findings in literature. DEMATEL method is chosen over the other methods for the pragmatic methodology used to construct and analyze the structural model involving causal relationship between multiple factors. It also integrates different expert knowledge that helps to investigate internal relationship and significance degrees of all the chosen factors. One advantage is that it can present a derived relationship through a cause-effect diagram. Critical factors through a visual structural model can be found, as well as the interdependent relationship amount factors are identified and evaluated while using DEMTEL. Key findings of the study revealed that human, economic, equipment and tools, management and environment factors have important impact of the effectiveness of the maintenance and the availability of the WtE plant, whatever the maintenance strategies from preventive to corrective maintenance through the condition maintenance. Quality, Lead time, Price and severity of spare part failure are keys criteria to consider while selecting spare part for WtE plant. The main limitation is that, the sample was a bit small since only few responds to the survey. Limitation of the thesis is related to the amount of the data collected. The findings cannot be generalized as it is affected by the limitation. The survey encounters probably the lack of cooperation from respondents as the study was not directly requested and done from their companies. It would be interesting to do further research of the topic by using data from different plants operated by the case company, to make the research more objective. This will help the case company knowing real issues their plants face. It could be interesting to do further research by focusing for instance on different locations and population because different climatic and environment factors may influence the failure rate of the plants items; dust, humidity, cultural factors