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Träfflista för sökning "hsv:(ENGINEERING AND TECHNOLOGY) hsv:(Mechanical Engineering) hsv:(Production Engineering Human Work Science and Ergonomics) srt2:(1990-1999)"

Sökning: hsv:(ENGINEERING AND TECHNOLOGY) hsv:(Mechanical Engineering) hsv:(Production Engineering Human Work Science and Ergonomics) > (1990-1999)

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1.
  • Brynzér, Henrik, et al. (författare)
  • Design and performance of kitting and order picking systems
  • 1995
  • Ingår i: International Journal of Production Economics. - 0925-5273. ; 41:1-3, s. 115-125
  • Tidskriftsartikel (refereegranskat)abstract
    • The results from a number of case studies carried out within a research project concerned with the design and performance of materials kitting systems are discussed. The focus is on the design of the kitting systems in terms of location of the order picking activity, work organization, picking method, information system and equipment. These design considerations are related to performance measurements, such as picking efficiency and picking accuracy, and are discussed in relation to the preconditions of the kitting system. In kitting systems, results show that picking efficiency and accuracy can be improved by making better use of the product structure when designing the picking information and when deciding the storage assignment policy. Also, batching of picking orders is cost efficient when extensive sorting and administration can be avoided. In general, combining the work roles of assembly and picking results in less administration.
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2.
  • Gadde, Lars-Erik, 1945, et al. (författare)
  • Utvecklingslinjer i byggsektorns distributionssystem
  • 1999
  • Ingår i: In Bröchner, J. and Josephsson, P-E. (eds) Proceedings of the Nordic Seminar on Construction Economics and Organization, pp. 171-178. Chalmers University of Technology, Sweden. ; , s. 171-178, s. 171-178
  • Konferensbidrag (refereegranskat)
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4.
  • Blinge, Magnus, 1963 (författare)
  • ELM: Environmental Assessment of Fuel Supply Systems for Vehicle Fleets
  • 1998
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • This thesis is based on the idea of applying a logistics approach to fuel supply systems. The complete supply chain from energy raw material to end use in the vehicle is analysed while keeping track of energy conversion efficiency, exergy consumption and emissions to air. This method, which is referred to as Energy Logistic Modelling (ELM), is heavily influenced by LCA practices. The viability of using this approach in the decision-making process of choosing fuel for a vehicle fleet is investigated. The emphasis is on organising and structuring life cycle inventories of fuels for entire fleets of vehicles and to give recommendations and guidelines for how to define system boundaries and allocation rules. ELM is suitable for assessing trade offs between changes of fuel or system boundaries and the above mentioned fuel supply chain measures, as well as technical modifications of the supply chain itself.
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6.
  • Franzén, Stig, 1943 (författare)
  • Public Transportation in a Systems Perspective A Conceptual Model and an Analytical Framework for Design and Evaluation
  • 1999
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Today urban areas are faced with problems like traffic congestion, air pollution, and limited accessibility and transport policy issues are focused on the "sustainable city of the future". For decision-makers the crucial question is how, with limited financial resources, a system for public transportation should be designed and developed to provide attractive travel and transport services. The basic problem is related to the systems design process itself, as the introduction of advanced applications based on new information and communication technologies will require a better understanding of public transportation in a systems perspective. By combining cognitive systems engineering and transportation systems analysis, relevant elements of control and communication theories (cybernetics) and human factors, a conceptual model and an analytical framework for public (mass passenger) transportation are developed. By use of a means-ends hierarchy of functional levels, the model describes five dynamic processes (the accessibility, travel, transport, traffic, and motion processes) in public transportation. Structural elements of the model (nodes for control functions, information collection and processing, and links for data and information flows) and their characteristics are identified and discussed. The framework and the model are, for validation purposes, applied in a design task (the realisation of an information centre for travellers and passengers) and in an evaluation task (an exploration and analysis of how incidents and disturbances are handled in Gothenburg). The complexity of public transportation is further explored, and control and data filtering needs on each functional level are identified and related to the potential of future dynamic interaction between actors on different functional levels. It is finally stated that the systems approach used to develop the model and the framework will become a necessary basis for future new ideas of how to promote the transportation of people by public means and, in that respect, the concept of intermodal passenger transport is critically assessed. The potential of the conceptual model and the analytical framework, to incorporate all possible means of transport (public and private) as well as to apply to the transportation of goods, is also discussed.
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7.
  • Hagman, Thore E.W. 1952 (författare)
  • Logistic Time Requirements in Fast Sea Transportation Systems
  • 1998
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The dissertation deals with logistic time requirements in fast sea transportation systems and the benefit of the application of the total time definition. The transportation engineering approach, to create new transport systems with high effectiveness, high service levels and also with high resource utilisation, has to some extent gained acceptance in the transportation industry, but it has not been fully realised that the transport system and the traffic system are not identical and that by focusing on high performance of the traffic system no guarantee is given that the transport system will become effective. This may be the explanation why, in the present rush for introducing high speed passenger services, the support systems have not been designed to match the performance at sea and the high energy and capital costs associated herewith. The main objective for moving passengers is normally to obtain the shortest possible time in the transport system. This goes for all transportation modes; air, land and sea and it has for waterborne transportation led to a shifting of interest from conventional ferries to fast ferries. In recent years speed at sea has been doubled at some ferry services, and as a consequence, sailing time has been reduced accordingly. Logistic time requirements in a ferry operation are related to the performance of the main system, the movement system and the supporting subsystems, like access systems, and if these work in sequence or to some extent in parallel. Time requirements in ferry operation can be divided into two categories; one operational category which includes cycle, sailing, and terminal time, and one category referring to the user of the provided service perspective, the total time. The total time is the time definition which is the most relevant to the passenger, as this is the time the passenger has to spend in the actual transportation system. An example (paper No IV) shows that an increase of the speed with 100% in the vessel movement system only gives a reduction of the total time in the transport system with 15%. The thesis includes six papers reporting data collected from fast and conventional sea transport systems.
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8.
  • Hultén, Lars A. R., 1964 (författare)
  • Container Logistics and its Management
  • 1997
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • In this work research on container logistics and its management is presented. Contrary to the common approach of treating this as a mathematical problem and addressing it by operations research methods, this work regards the problem in a wider perspective. Instead of being limited to management of the physical system bringing about the movement of containers, container logistics management is regarded as also including demand management. The research aims at describing the logistics of the system in terms of how the various components in a container transport system interact and how the system interacts with its environment. Due to the limited previous research on container logistics and its management in a wider perspective, this work is primarily explorative and descriptive. Empirical studies of container flows are presented. Both the flow for an individual carrier and the total flow between a port and its hinterland have been studied and the studies reveal a low utilization of the containers. Containers were found to be stored empty for long periods of time at terminals, retained for a considerable time by customers and there was much transport of empty containers. The studies also revealed poor quality of the data in the computerized tracking systems with missing and erroneous data entries. In a study of ten of the world's twenty largest container shipping companies it was found that the use of advanced decision support systems, taking advantage of operations research or artificial intelligence technology, was scarce. Only one company reported to use such a system, which assigned priorities to depots, in day-to-day operations. The main logistical functions of the container are to create opportunities to exploit economies of scale and enabling vessels and vehicles to operate independently by decoupling them at terminals. Therefore, when deciding on actions to improve the utilization of containers the effect on other system components must be considered. Pooling is suggested as a way of increasing the utilization of the containers without constraining the operation of other, capital intensive, resources. Container logistics systems are characterized by high complexity and uncertainty. Much of the information relevant for decision-making is informal and the managers' experience is difficult to formalize. Therefore successful systems for container logistics management must take advantage of both human and computerized information processing. It is suggested to engage theories from cybernetics and information theory as a theoretical framework for logistics systems analysis. Even if this is only done to a limited extent in this research, due to being considered at a late stage of the research, these theories show a strong explanatory ability.
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9.
  • Jahre, Marianne, 1963 (författare)
  • Logistics Systems for Recycling - Efficient Collection of Household Waste
  • 1995
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • This dissertation investigates collection and recycling of household waste with focus on packaging materials. The purpose is how to describe and explain the d esign of a collection system according to different system environments in orde r to achieve high logistics performance in terms of low cost and high service. The research approach consists of two main parts. First, data on existing syst ems are collected and analysed. Then a model is used to analyse cost consequenc es from changes in the system and the environment. Four main properties of reverse distribution channels were identified including the number of distribution levels and distribution points, whether the system is bring or kerbside, the degree of separation at source and the degree of co- collection. The study further demonstrates that performance can be measured in a number of ways including service toward end-markets and households, costs, en vironmental consequences and programme ratios. Finally, two main environmental factors identified were population density and the number of materials being co llected in the system. The major conclusion from the study is that systems in areas with low populatio n density should collect and recycle few materials that should be separated at the source and then co-collected. Systems in areas with high population density, on the o ther hand, may collect many materials, but then centralized separation (i.e. processing in a MRF) should take place.
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10.
  • Lindau, Roger, 1961 (författare)
  • The Impact of High-Quality Information on Performance in Manufacturing
  • 1995
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The dissertation deals with the impact of high-quality information on performance in manufacturing. In a system where two material flows with sequence dependency are matched, the use of real-time information to monitor and control the sequencing buffer improves the system's ability to schedule many different models, compared with a system with no information at all. In the latter case, the system is upset considerably when more than four different models enter the system. The use of automatic data capture systems enhances productivity in manufacturing companies. Six case studies were carried out, all of which showed that the productivity improvements obtained by these systems are mainly in the area of human resource utilisation which was found in all six case studies. Improvements in machine utilisation, transporter utilisation and inventory levels were also found. The productivity can furthermore be improved if the installed system acts as a proactive system, giving information on the operational level about deviations and changed customer demands. Out of 31 registered disturbances, 15 resulted in a productivity loss because scheduling information was not available. A system providing scheduling information makes it possible for the scheduler to change a dispatch list or final assembly schedule in such a way that a less important job can be run ahead of a delayed important job, only to release capacity when the delayed job arrives. These kinds of systems mainly enhance productivity in an environment with shared resources. The impact of providing the scheduler with real-time information of high quality is investigated. It is shown that this enables him to reschedule the work force when stochastic events such as disturbances of different kinds affect the scheduling environment. It is also shown that the performance of the scheduled system improves a/ in direct relation to the number of work stations being scheduled and b/ with the reduction in lapse between the detection of a deviation and corrective action. Measures taken to prevent the propagation of disturbances can be classified as formal measures and informal actions. Formal measures are such measures which are defined in a computer system, and informal actions are such that are executed manually. None of the measures identified in this study were efficient when a holistic evaluation was made. This evaluation describes the ability of the measure to absorb disturbance effects, its cost and the degree to which it upsets the system. Some measures were, however, better than others. Partial delivery is a suitable action when materials shortages occur, subcontracting when machines break down, and moving over personnel when absenteeism occurs. When an ADCS is used, two types of effect can be experienced; direct effects and indirect effects. The direct effects are the result of the data capture process as such being enhanced, i.e. less effort is needed to capture data and to trace and correct faulty data, and the indirect effects are the effects experienced when timely and accurate data is fed into the data base from which a number of functions retrieve the data. The direct effects are normally easy to define. They affect the number of staff involved in data capture and handling, and in some cases safety stock levels. Indirect effects are more difficult to isolate. A general model showing the manufacturing process and the different ADCSs which can be found within each activity was developed. Indirect effects experienced as a result of enhanced decision-making when an ADCS is installed were; increased sales, decreased costs and decreased inventory investments. Both direct and indirect effects enhance the effectiveness of a company. It is shown how the use of a serial information flow respectively a parallel information flow with different time delays affects the performance of a system when expediting is carried out. The results indicate that a parallel information flow, i.e. information to the succeeding activities being given in advance, performs best if the information quality is high, i.e. the time delay is close to zero. When the time delay increases there is a threshold when the serial information flow performs better than the parallel information flow with poor information quality. The performance of the parallel system decreases with poor information quality. The same result is obtained with respect to the output, i.e. the output decreases with poor information quality.
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11.
  • Medbo, Lars, 1957 (författare)
  • Materials Supply and Product Descriptions for Assembly Systems - Design and Operation
  • 1999
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • This thesis discusses and reports on assembly systems design, concerning manual assembly of complex products involving production with requirement for flexibility in production volumes and product variants. The research is based on more than a decade of work within the Swedish automotive industry focusing on parallel product flows and long cycle time assembly work. The work has been accomplished in close co-operation with the industry based on both theoretical and practical frames of reference dating back to the 1970s. The work has resulted in implemented assembly systems organised in work groups and materials supply by means of materials kitting. Product descriptions have been found to be crucial regarding design of assembly systems including materials supply. An assembly oriented product structure has proved to be a significant key factor in this context. To achieve such a structure is a matter of reforming the traditional (abstract) product descriptions, which are based on and include the general design oriented product structure. Materials kits have proved to be a feasible way to accomplish the materials supply, since the materials kit functions as a work instruction and both materials supply and operator learning are enabled. Thus, materials kits bridge two inter-linked restrictions, for full-scale parallel flow, long cycle time assembly systems. The thesis explains how to reform traditional product descriptions by, for example, introducing a method for assembly systems design. The method is principally based on the information available in the design oriented product structure and utilises the physical components of the product to design intra-group work patterns and materials kits to achieve so-called structural congruence. This congruence is one key factor for the so-called materials kit configuration, which in turns leads to high materials kits functionality and reformed product descriptions. It is also shown that available product variant specifications and product variant identification procedures, applied in line assembly, lead to complex descriptions. Methods that reduce this complexity due to applications in long cycle time assembly are reported. Observed effects of applying such descriptions and methods are foremost described through case studies, which report on observed work pace in long cycle time assembly work and as well as how parallel work groups performed their assembly work. These results illustrate that there does not need to be a contradiction between humanisation of work and efficiency, or between efficiency and flexibility. The use and need of appropriate abstract product descriptions are especially demonstrated through the possibility to utilise assembly oriented product structures as the fundament in design of assembly systems, work instructions and product variant descriptions.
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13.
  • Onori, Mauro, 1961- (författare)
  • Kapitel 14.- Off-Line Programmering
  • 1992
  • Ingår i: Master of Science Course Litterature. - Linköping & Stockholm : Linköping Inst. of Technology & Royal Inst. of Technology.
  • Bokkapitel (refereegranskat)
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14.
  • Petzäll, Jan, 1949 (författare)
  • Design for Accessibility: The Development of Public Transport Vehicles with Regard to Mobility Impaired Passengers
  • 1993
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The objective of this thesis is to show how a knowledge basis and requirements for vehicles, for the accommodation of mobility impaired people, can be worked out and specified through experimental studies with selected groups of subjects as well as how requirement specifications can be formulated for use in the development process of vehicles. The overall hypothesis underlying this thesis is that integrating the requirements of mobility impaired people in the normal development process of vehicles produces a superior vehicle compared to redesigning or modifying a complete vehicle. A working method for the development is proposed, based on the development process used by vehicle manufacturers and on a user oriented product development process, focusing on the analysis of the user in the use situation. The work contains experimental studies of defined subsystems of vehicles, carried out with selected groups of subjects, for the purpose of specifying the functional requirements on the shape, dimensions and performance of the systems. The experimental studies have dealt with entrances and seats in buses, entrances of taxi cars, wheelchair and occupant restraint systems and the traversing of step obstacles with manual wheelchairs. A description and analysis of the development process of vehicles and a user oriented product development process are presented as well as a case study showing an example of how to define a requirement specification for buses based on the results of the experimental studies carried out. Principles for the selection of test subjects, methods for the recording and analysis of data as well as for dealing with conflicting requirements are discussed.
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15.
  • Shahriari, Mohammad, 1945 (författare)
  • Safety at Rail-Road Level Crossings
  • 1993
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Safety related to traffic at rail/road level crossings has long been a major issue for rail operators all over the world. Eliminating these level crossings entirely would be a desirable solution. However converting them into separate types is very expensive and not reasonable in many cases, e.g. where the traffic intensity is low. For this reason a research program should be started aimed to meet the following main requirements: 1. The safety awareness of the driver as the main decision-making unit should be increased. This may help him/her accept a lower risk when intending to pass over a level crossing. 2. Crossings should be designed to provide more convenient information to the driver. 3. Tail vehicles should be deisgned to protect the passengers in a critical collision situation. This thesis summarises some research studies concerning the above-mentioned requirements. In papers I and II, road driver behaviour at passive crossings is focused. A decision model for a simulation program was developed. The purpose of the study reported in papers III and IV was to find out whether risk analysis methods either forwards or backwards, could successfully explain the mechanism responsible for the occurrence of collisions at rail/road level crossings. The results show that application of these methods at a disaggregate level is feasible in order to explain single accidents. Paper V.1 and V.2 analyse a situation in which a light rail bus, travelling at 130-140 km/h, collides with a stationary heavy truck. The aim was to find out whether a combination of energy absorption capacity and some type of emergency brake system would offer increased protection to passengers in light rail vehicles. The results of the study indicate that under some realistic assumptions a survival impact speed as high as 70 km/h can be achieved, provided that the rail vehicle is fitted with a deformation zone of 1.5 m length, and an emergency retardation rate of up to 3.5 m/s.
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16.
  • Wedel, John E., 1956 (författare)
  • Lead-Time Reduction in Manufacturing - from Initiation to Realisation
  • 1996
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • This work deals with reduction of lead-time in manufacturing. The overall research problem focuses on how to ensure high efficiency in this process, and the research area includes how the reduction process is managed. The aim of the work is to increase the knowledge of planned changes and, in line with this, to increase knowledge about basic conditions for change, so that reductions can be better controlled. The work is based on six papers, each concentrating on one part of the process. Both quantitative and qualitative methods are used. The papers imply that reduction of lead-time is a complex process in which many conditions and factors interact, influencing the results. Even though the process can be described as a limited number of steps, this does not mean that it is simple to control. In each step, there are several issues to consider. The results also imply that companies who do not improve their lead-time performance significantly, will be less competitive. Small improvements are not enough, since other companies are making great progress. There are different types of forces, which are not the same in the beginning of as during the process. This means that control has to be active and flexible with continuous analysis. A company which isnot aware of this transformation of driving forces will be unable to promote the right forces as well as to direct resources and power towards the right restraining forces or obstacles. Goal setting can be managed differently, but an active approach has proved to yield good results. Motivation influences the magnitude of the goals, which implies that striving towards high goals is difficult without motivation. The implementation can be categorised by different approaches. Broad approaches combining demands for co-ordination and commitment have proved to be successful. When reductions have been achieved, this should be reflected in the basic files for planning.
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17.
  • Woxenius, Johan, 1967 (författare)
  • Development of Small-Scale Intermodal Freight Transportation in a Systems Context
  • 1998
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • An intermodal freight transportation system is characterised by the subsequent use of different transportation modes for moving goods stowed into unit loads from the consignor to the consignee. Typically, it involves a wide variety of activities, actors and resources, which implies a certain degree of technological as well as organisational complexity. Other distinctive features are dependency on surrounding systems and a general lack of formal systems management as well as of objectives shared among all actors. This dissertation focuses the need for a renewal of the European intermodal transportation system that has not yet been able to fulfil the high expe ctations from society. Most of the commercial problems are directly or indirectly related to the complexity of the system and the scale in which the services are produced in. The solution foreseen and advocated in this dissertation is to divide the operations between the layers direct shuttle trains, corridor trains and locally adapted small-scale network modules, of which the latter layer is especially treated. Special attention is paid to the issue of connecting the layers as well as the different network modules. An outspoken systems approach is applied and a framework model is chiselled out from theories on general systems, transportation systems as well as on intermodal transportation systems. The object of study is successively narrowed, focusing technical matters and small-scale operations on lower system levels. The complexity and lack of systems management implies that implementing new technical resources involves distinctive barriers that are described and classified. Approaches for reducing the effects of barriers include to conform to standards, to create closed systems and to implement new resources gradually. Another issue addressed is the suitability of transshipment technologies for different network operation principles and national preconditions. Small-scale transshipment technologies - all of which are described in a detached appendix - are evaluated against an outlined list of requirements. The argumentation is finally applied to the intermodal freight system that received the highest score in the evaluation - Swedish State Railways' Light-combi project.
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18.
  • Öjmertz, Birgitta, 1969 (författare)
  • Materials Handling from a Value-Adding Perspective
  • 1998
  • Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • The keen competition in industry puts a great deal of pressure upon all parts involved, and in addition to demands on the physical product, there are demands on the service aspects, such as an increased demand on the configuration of the delivered materials and their packaging, on throughput time, timeliness, and increased cost efficiency. The performance of the materials flow systems, in which materials handling constitutes an important part, therefore plays a crucial part in the strive for competitive advantage. The materials handling function contributes to the adding of value when, for example, mixing articles, packaging them as demanded by the customer, or orienting and positioning them for a later process step, as well as influences cost efficiency and throughput time. This thesis deals with the relation between the resources required for the materials handling function and the design of materials flow systems and is directed towards the development of a method for evaluation and improvement of materials flow systems regarding the performance of the materials handling function. The development of a conceptual framework for the perspective of materials handling as contributing to the value added in materials flow systems is included as an important basis. An improved understanding of the purpose of the materials handling function, as well as principles and procedures for how to utilise this knowledge to evaluate and improve the performance in terms of efficiency, is provided. The research was directed towards theory building, and a primarily inductive approach has been adopted, where the empirical data was gathered in ten case studies mainly within the manufacturing industry and warehousing. A method was developed which makes it possible to estimate, in an early design stage, the efficiency of the materials handling function, and to identify where along materials flows that changes in the materials flow system design would give prerequisites for improvements. Further, the efficiency measurement has been utilised in a study aiming at relating the efficiency of the materials handling function to the process localisation in the context of the automotive industry and outsourcing. Additionally, the thesis includes a method for simultaneous evaluation of the materials handling efficiency and the physical work load generated in a materials flow system, the Work-Load Dose method.
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19.
  • Hanson, Lars, et al. (författare)
  • ANNIE, a Tool for Integrating Ergonomics in the Design of Car Interiors
  • 1999
  • Ingår i: SAE technical paper series. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0148-7191. ; 108:5, s. 1114-1124
  • Tidskriftsartikel (refereegranskat)abstract
    • In the ANNIE project - Applications of Neural Networks to Integrated Ergonomics - BE96-3433, a tool for integrating ergonomics into the design process is developed. This paper presents some features in the current ANNIE as applied to the design of car interiors. A variant of the ERGOMan mannequin with vision is controlled by a hybrid system for neuro-fuzzy simulation. It is trained by using an Elite system for registration of movements. An example of a trajectory generated by the system is shown. A fuzzy model is used for comfort evaluation. An experiment was performed to test its feasibility and it showed very promising results.
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22.
  • Aardal, Karen, et al. (författare)
  • On the resemblance between the Kornai-Liptak and cross decomposition techniques for block-angular linear programs
  • 1990
  • Ingår i: European Journal of Operational Research. - : Elsevier BV. - 0377-2217 .- 1872-6860. ; 46:3, s. 393-398
  • Tidskriftsartikel (refereegranskat)abstract
    • In this paper the resemblance is demonstrated between the master- and subproblems generated by the Kornai-Liptak algorithm and the subproblems obtained by using the cross decomposition method on linear optimization problems with block-angular structure. The significance of the similarity between these two algorithms becomes apparent considering the main disadvantage attributed to cross decomposition. In cross decomposition a master problem has to be solved from time to time since the subproblems alone do not always give a converging sequence of primal and dual solutions. But if the cross decomposition algorithm is modified in such a way that the successive primal and dual subproblem solutions are taken into consideration with equal weights, this results in the Kornai-Liptak algorithm for which convergence is guaranteed
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23.
  • Aas, Gro Hanne (författare)
  • Kvinneforskningspolitiske (pr)øvelser
  • 1999
  • Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
    • Målsettingen for licentiatuppsatsen er å analysere nordisk kvinneforsknings formuleringer av forskningspolitiske felter, problemstillinger og utfordringer, og gjennom kontakt og diskusjon bidra til samarbeid, diskusjoner og offentlighet om forskingspolitikk i kvinneforskning. Arbeidet har tatt utgangspunkt i relativt nytt materiale fra Danmark, Norge og Sverige. I kap. 1 presenteres prosjektet, problemstillinger og materiale. Kapitlene 2-6 består av innledninger og artikler holdt eller skrevet i løpet av de to senaste åren. Diskusjoner om kjønn og akademia står i fokus i kap. 2 - "Universities have politics". I kap. 3, artikkelen "Gamle og nye drømmer", diskuteres et kvinneforskningspolitiske intervensjonsprosjekt som blev utført for en del år tilbake, og det antydes noen nye omdreiningspunkter for et slikt arbeid. Enkelte perspektiver utdypes i kap. 4, "Kvinneforskningens samfunnskontrakt", hvor termen "kvinneperspektiv" som forskningspolitisk term granskas krtitiskt. De to siste kapitlene tar utgangspunkt i den norske forskningsmeldingen som kom våren 1999. Ut fra tre lesestrategier forsøkes det leses muligheter for kvinneforskningspolitiske strategier. Det ses også på innholdet i regjeringens forskningspolitiske verdidebatt, og det diskuteres mulige intervensjoner i denne ut fra feministiske vitenskaps- og teknologistudier.
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25.
  • Abeysekera, John, et al. (författare)
  • Body sizes and other human factors differences between Swedish and foreign students in Swedish universities
  • 1994
  • Ingår i: Ergonomics for Quality Life. - : PPCOE. ; , s. 420-423
  • Konferensbidrag (refereegranskat)abstract
    • Past studies have shown large differences in body size between people of Industrialized Countries (ICs) and Industrially Developing Countries (IDCs). These differences can have negative effects on the usage of technology which IDCs today acquire to a great extent from ICs. At the same time, the number of students from IDCs seeking education and training in universities in ICs is increasing. This paper reports on the impact of human factors differences particularly body size differences between foreign and local students on the use of university facilities, based on anthropometric and questionnaire surveys carried out on a small scale by foreign graduate students of Lulea University, Sweden. The study revealed large differences in body sizes between local and foreign students. The questionnaire survey of foreign students showed that there are other significant human factors differences such as the use of a foreign language, viz. Swedish which is unique to Scandinavia, and the exposure to long cold winters. Whether these differences in human factors influence the acquisition of knowledge or learning capacity of foreign students is worth further investigation.
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26.
  • Abeysekera, John D.A., et al. (författare)
  • A Scandinavian perspective on human factors testing of personal protective devices
  • 1997
  • Ingår i: Performance of protective clothing. - West Conshohocken, Pa : ASTM International. - 0803124023 ; , s. 283-292
  • Konferensbidrag (refereegranskat)abstract
    • Testing for protection performance and human factors in personal protective devices (PPD) can be undertaken using a standardised methodology. The standardised methodology for performance testing is used for the certification of PPD. However, it is unfortunate that methods of testing for human factors and wearability of PPD are scarce, and even the methods that do exist are not always refined or standardised. In both hot and cold environments, thermal comfort is an important user need of PPD. To test the thermal characteristics of PPD, methods providing objective data are available, yet they are not always standardised. An exception exists for insulation testing of clothing, for which standardised methods have been developed. The fit of PPD is also a priority need among wearers. Clothing fit is often tested subjectively. The objective methods developed to test the fit of PPD and clothing again require refinement and standardisation. Wearability of PPD urgently requires the development and standardisation of both objective and subjective testing methods. This paper provides insights into some testing methods on human factors of PPD that have been particularly useful over the years.
  •  
27.
  • Abeysekera, John D. A., et al. (författare)
  • Adaptation to discomfort in personal protective devices: an example with safety helmets
  • 1990
  • Ingår i: Ergonomics. - : Informa UK Limited. - 0014-0139 .- 1366-5847. ; 33:2, s. 137-145
  • Tidskriftsartikel (refereegranskat)abstract
    • Discomfort in the use of personal protective devices (PPD) has been one of the chief causes of their non-use. A field trial using industrial helmets was carried out to ascertain whether by training and repeated wearing subjects could experience a significant adaptation to discomfort. Ten subjects took part in the trial in a tropical environment by wearing helmets repeatedly (6 h a day) for one month. Subjective evaluations of discomfort were made at the end of the 1st, 3rd, 5th, 14th and 30th day. It was revealed that complaints of discomfort, viz. hotness, heaviness, bad fit, etc., decreased markedly throughout the 30 day period. Though positive responses of adaptation to discomfort seem to reach an optimum towards 30 days, it is difficult to draw any conclusions on the optimum period of adaptation for each discomfort factor. In relation to inherent discomforts that are extremely difficult to overcome without compromising the protection efficiency of a PPD, the principle of adaptation seems to be a very important facet which has to be developed for an effective PPD programme.
  •  
28.
  • Abeysekera, John D.A. (författare)
  • Ergonomics and technology transfer
  • 1990
  • Ingår i: International Journal of Industrial Ergonomics. - 0169-8141 .- 1872-8219. ; 5:2, s. 181-184
  • Tidskriftsartikel (refereegranskat)
  •  
29.
  • Abeysekera, John D.A. (författare)
  • Ergonomics for effective collaboration
  • 1997
  • Ingår i: African Newsletter on Occupational Health and Safety. - 0788-4877. ; :2, s. 27-
  • Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
  •  
30.
  • Abeysekera, John D.A., et al. (författare)
  • Ergonomics in developing countries
  • 1990
  • Ingår i: Advances in industrial ergonomics and safety 2. - : Taylor and Francis Group. - 0850667488 ; , s. 771-778
  • Konferensbidrag (refereegranskat)
  •  
31.
  •  
32.
  •  
33.
  • Abeysekera, John D. A., et al. (författare)
  • The need for research on human factors regarding personal protective devices in the cold environment
  • 1996
  • Ingår i: Performance of protective clothing. - West Conshohocken, Pa : ASTM International. - 0803119879
  • Konferensbidrag (refereegranskat)abstract
    • The human factors or wearability needs of personal protective devices (ppd) and clothing (ppc) worn in the cold environment become more important as they must compromise with, and be adapted to, the clothing worn for cold protection. The occupational risks among outdoor workers in the cold can be aggravated if the wearability demands of ppd are not met. Failure to adequately meet user needs in currently used ppd in the cold environment has resulted in discomfort, injury, non-use and performance decrement among outdoor workers, particularly in the extreme cold regions. A preliminary study consisting of a literature survey in popular data bases and questionnaire survey among users of ppd, were carried out to ascertain what studies have already been conducted in this area and whether a wearability problem really exists among users, respectively. The literature revealed some specific areas where wearability problems exist and some research carried out on methods of testing of ergonomic characteristics of ppd. The questionnaire among ppd users in the cold climate confirmed that the workers do confront many inadequacies in the use of ppd. A case study carried out on ergonomic demands of safety shoes in the cold climate among users, manufacturers and experts revealed a similar trend of demands and priorities in ergonomics of shoes among all three groups. From the findings of the preliminary study it can be concluded that human factors research in ppd and particularly ppd worn on body extremities, viz. safety helmets, shoes and gloves, for use in the cold environment, seem urgent. Some research needs in the development of methods of testing for ppd evaluation are suggested.
  •  
34.
  •  
35.
  • Abeysekera, John (författare)
  • Ergonomics aspects of personal protective devices
  • 1993
  • Ingår i: Occupational and environmental economics. - : Indian Society of Ergonomics.. - 819005080X ; , s. 109-114
  • Konferensbidrag (refereegranskat)abstract
    • The use of a personal protective device (ppd) is a widely accepted method of safeguarding workers from occupational hazards in industrialized countries (IC) and an important method employed in developing countries (DC). Though protection is assured if the devices are worn constantly, it is unfortunate that due to discomfort and inconvenience, the majority of those exposed to hazards do not wear them. DCs which mainly import ppds from ICs are confronting many ergonomics problems, because the equipment designed for IC conditions is inappropriate for use in DCs, due to significant differences in user body sizes, environments and working methods. A questionnaire survey conducted among ppd manufacturers in 11 ICs revealed that 90% followed standards in manufacturing. Another survey conducted among health and safety authorities who responded on behalf of ppd users in 35 DCs revealed that the most common ergonomic causes of non-use are stresses from hotness, weight, improper fit and obstruction at work. While manufacturers place greater emphasis in the protection performance of the equipment, users in DCs refuse to wear it because the comfort needs are not fulfilled. Developing ergonomics standards for ppds seems to be a feasible way of persuading the manufacturers to provide ergonomic values in ppds. The need for maximum allowable comfort in the design, taking into consideration the user characteristics and protection factor is emphasized. To overcome the inherent discomforts that are extremely difficult to reduce without compromising the protection efficiency of a ppd, the principle of user adaptation seems to be a very important facet which has to be developed. A case study on safety helmets is reported. The use of a personal protective device (ppd) is a widely accepted method of safeguarding workers from occupational hazards in industrialized countries (IC) and an important method employed in developing countries (DC). Though protection is assured if the devices are worn constantly, it is unfortunate that due to discomfort and inconvenience, the majority of those exposed to hazards do not wear them. DCs which mainly import ppds from ICs are confronting many ergonomics problems, because the equipment designed for IC conditions is inappropriate for use in DCs, due to significant differences in user body sizes, environments and working methods. A questionnaire survey conducted among ppd manufacturers in 11 ICs revealed that 90% followed standards in manufacturing. Another survey conducted among health and safety authorities who responded on behalf of ppd users in 35 DCs revealed that the most common ergonomic causes of non-use are stresses from hotness, weight, improper fit and obstruction at work. While manufacturers place greater emphasis in the protection performance of the equipment, users in DCs refuse to wear it because the comfort needs are not fulfilled. Developing ergonomics standards for ppds seems to be a feasible way of persuading the manufacturers to provide ergonomic values in ppds. The need for maximum allowable comfort in the design, taking into consideration the user characteristics and protection factor is emphasized. To overcome the inherent discomforts that are extremely difficult to reduce without compromising the protection efficiency of a ppd, the principle of user adaptation seems to be a very important facet which has to be developed. A case study on safety helmets is reported.
  •  
36.
  • Abeysekera, John, et al. (författare)
  • Ergonomics in Sri Lanka : a means to productivity development
  • 1996
  • Ingår i: 4th Pan-Pacific Conference on Occupational Ergonomics. - : Ergonomics society of Taiwan. ; , s. 323-327
  • Konferensbidrag (refereegranskat)abstract
    • Sri Lanka has declared 1996 as the 'Year of Productivity'. With a significant share of her national income being diverted for defence and security, productivity development becomes supreme for Sri Lanka's economic survival. Ergonomics or human factors which is a science well known for improving working conditions, is hardly known in Sri Lanka. Ergonomics applications enhance job satisfaction and productivity and maximise the product or systems quality by improving usability. A recent survey of three randomly selected large industrial work establishments in Sri Lanka revealed that much mismatch exists between workers and the machinery they are forced to work with, which hampers productivity and causes friction in the work places. A series of lectures conducted by an ergonomist among different professional groups and university students helped to create considerable awareness of the science of ergonomics. The participants were convinced that ergonomics can contribute immensely to productivity development in the country. Some strategies for ergonomics education in Sri Lanka which can also be adopted in other similar industrially developing countries are proposed.
  •  
37.
  • Abeysekera, John, et al. (författare)
  • Human factors of clothing and work-wear : a review
  • 1994
  • Ingår i: Proceedings. - Kiel : German Society of Physiological Anthropology. ; , s. 137-142
  • Konferensbidrag (refereegranskat)abstract
    • An extraordinarily large share of research carried out in the near past on clothing comfort has been in the area of thermal comfort. Accordingly standards, norms and guidelines on thermal requirements of work-wear have been developed. Through behavioural adjustments people have learned to achieve thermal comfort even if the work clothes have slight deficiencies in thermal characteristics. It is beyond doubt that the thermal characteristics need careful consideration in the manufacture of work clothes. At the same time one must be aware that other human factors can also influence the overall wearability of clothing. This paper reviews the wearability and comfort of the clothing and work-wear to provide better understanding of the priorities in user needs in work clothes which can help plan future research and the need for new standards
  •  
38.
  •  
39.
  • Abeysekera, John, et al. (författare)
  • Some design recommendations to improve comfort in helmets : a case study from China
  • 1996
  • Ingår i: Journal of Human Ergology. - 0300-8134. ; 25:2, s. 145-154
  • Tidskriftsartikel (refereegranskat)abstract
    • Unless the basic user needs are satisfied in safety helmets, it is difficult to get workers to wear them habitually and for long periods. Hotness, weight and fitting problems are major wearability issues that require improvements. The enormous need for an optimally designed helmet in China prompted a case study on comfort aspects in helmets. The subjective impressions of the wearers of test helmets provided useful information for design changes to improve comfort. The heat transfer measurements through helmets indicated the need for ventilation openings to be provided on the shell of plastic helmets. Due to the advantage of low weight and good ventilation, it is recommended that cane helmets be further developed to improve protection, wearability and durability, and subsequently be produced in large scale
  •  
40.
  • Abeysekera, John (författare)
  • Some ergonomics issues in the design of personal protective devices
  • 1992
  • Ingår i: Performance of protective clothing. - Philadelphia, Pa. : ASTM International. - 0803114303 ; , s. 651-659
  • Konferensbidrag (refereegranskat)abstract
    • The use of personal protective devices (ppd) is an important method to safeguard workers from occupational hazards both in industrialized and developing countries. Surveys have indicated that majority of those exposed to hazards are reluctant to use ppd because they are uncomfortable for such reasons as hotness, heaviness, ill fit, inconvenient, etc. Investigations have revealed that user-centered designs which satisfy the human factors needs of ppd, can reverse this trend and make ppd more acceptable. Because a questionnaire survey has shown that manufacturers are more inclined to adhere to standards, developing ergonomic standards seems to be a feasible method to persuade the manufacturers to provide the user needs in the design. Any unavoidable discomforts in ppd can be controlled by adaptation of users to ppd wearing.  
  •  
41.
  •  
42.
  • Abeysekera, John (författare)
  • The use of personal protective clothing and devices in the cold environment
  • 1992
  • Rapport (övrigt vetenskapligt/konstnärligt)abstract
    • In the use of personal protective devices (ppd) in the cold environment the wearability problems become more aggravated as the ppd must be worn over the cold protective clothing. Research in the area of human factors of ppd in cold environment has been scarce in the past. The lack of adequate user needs in currently used ppd in the cold environment, has resulted in discomfort, injury, non-use, and performance decrement among outdoor workers, particularly in the extreme cold regions, viz. Arctic countries. A preliminary study on the 'state of the art' was carried out on the use of ppd in cold environment which consisted of a literature survey, questionnaire survey among outdoor workers and information search through visits to relevant research institutions, discussions with researchers and participation in Conferences. The literature search carried out in 6 data bases revealed useful information about specific areas where wearability problems exist in ppd as well as some methods to be employed in research. The results of the questionnaire survey carried out in the Luleå region confirm that workers confront many inadequacies in the use of ppd in the cold climate. From the findings of this preliminary study three important kinds of ppd viz. safety gloves, safety shoes and safety helmets are discussed in this report. Human factors research for ppd in the cold environment with a view for improvement of wearability and use seem urgent.
  •  
43.
  •  
44.
  • Abrahamsson, Kenneth (författare)
  • Adult education in Sweden and the United States : Working Life in Sweden No. 38
  • 1990
  • Rapport (populärvet., debatt m.m.)abstract
    • All young persons in Sweden have to complete 9 years of basic compulsory schooling. More than 95 percent opt for an additional 2 or 3 years of upper secondary school, after which they have free access to further education. The system of adult education is designed to bridge the gaps between generations and to provide opportunities for recurrent, lifelong education. The traditionally strong position of adult education is partly tied to the large number of providers. Formal adult education comprises basic education operated by authorities through government grants and municipal adult education. Popular adult educational activities are studies at folk high schools or under the aegis of adult educational associations. Labor market training takes the form of specially organized vocational training or uses the regular educational system. Personnel education and inservice training are educational activities aimed at employees and organized on the employers' terms and at their expense in companies and national or local authorities. The government has tried to establish the necessary preconditions for adult educational activities, including adult education in all municipalities, educational financing, educational leave, studies as part of the renewal of working life, and adult education as an expression of general welfare policy
  •  
45.
  •  
46.
  •  
47.
  • Abrahamsson, Kenneth (författare)
  • Arbetstiden som forskningsfält
  • 1998
  • Ingår i: Arbetstiden, jobben & framtiden. - Stockholm : Arbetsmiljöfonden. - 9188530639 ; , s. 15-21
  • Bokkapitel (populärvet., debatt m.m.)
  •  
48.
  • Abrahamsson, Kenneth (författare)
  • Arbetstider i olag
  • 1998
  • Ingår i: Arbetstiden, jobben & framtiden. - Stockholm : Arbetsmiljöfonden. - 9188530639 ; , s. 7-14
  • Bokkapitel (populärvet., debatt m.m.)
  •  
49.
  •  
50.
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