1,720,958 research outputs found
Use of Advanced Planning and Scheduling (APS) systems to support manufacturing planning and control processes
No full textAn Advanced Planning and Scheduling (APS) system is defined as any computer program that uses advanced mathematical algorithms or logic to perform optimization and/or simulation on finite capacity scheduling, sourcing, capacity planning, resource planning, forecasting, demand planning and others. Relative the massive interest, both from academia and industry in the subject area of manufacturing planning and control, there has not been much written about the use of APS systems in practice. For academia, this means a lost opportunity of understanding benefits and problems of implementing and using advanced planning and scheduling approaches. Seeing the many algorithms developed by academia during the years that never have been put into practice this should be valuable knowledge. For practitioners, the many failed implementations should make it important to understand what could be expected when implementing an APS system and what is required to effectively use it. This thesis studies how APS systems can support manufacturing planning and control (MPC) processes in adding value to the company by focusing on the consequences of using APS system and the variables influencing the consequences of using APS systems. It is different from previous studies concerned with APS systems as special focus is given to the use, i.e. when the APS system is operated in the MPC process instead of the implementation, the phase between the software selection and going live. Four case studies and one survey have been conducted to aid in fulfilling the overall aim.
The thesis found that the use of an APS system can support MPC processes by improving the decision support, simplifying planning activities, and reducing planning time and by generating feasible plans and schedules that are possible to follow. Still, the use of an APS system might make the planning activities more difficult to conduct and result in plans and schedules that are difficult to retrace or which are incorrect. It was identified that not only the use or non use of APS functionalities, but also the way the functionalities are used and the extent to which the functionalities are used influences the MPC process. The planning environment complexity, identified as the number of/and dependencies between entities and uncertainties in demand, supply and the production system of a manufacturing company, was found to influence how the APS system ‘should’ be used. Variables connected to the implementation of the APS system and to the MPC process, on the other hand, influence how the APS system is actually used. This thesis should be of interest to the subject area manufacturing planning and control. Researchers may benefit from definitions and conceptualisations of a number of constructs. For managerial usage, a number of benefits from using APS system in different MPC processes have been identified. Those may be used as a tool to assess whether the potential benefits of APS systems support the overall business objectives. Alternatively, it can be employed as an evaluation mechanism to access whether anticipated benefits were realized. A number of variables of importance in order to use an APS system in such a way so that benefits could be achieved have been identified. Those should be important when considering an APS system implementation. The thesis also contributes with a number of case descriptions in how APS systems are used in different companies and the users perceptions of using APS systems. This could be interesting knowledge for consultants and system vendors
Shop floor characteristics influencing the use of advanced planning and scheduling systems
No full textThe purpose of this article is to investigate how the manufacturing process, the shop type and the data quality, i.e. the shop floor characteristics, influence the use of advanced planning and scheduling (APS) systems in production activity and control (PAC). The methodology implemented is a multiple case study at three case companies. Each company has different shop floor characteristics, but all use a scheduling module in an APS system, which supports production scheduling. A theoretical framework is developed suggesting how APS system are used in the PAC activities, and which major aspect to consider. The case analysis shows that the scheduling module in APS system, foremost supports sequencing and dispatching. In particular, the shop type is influenced by the decision of how often the APS runs and what freedom is given to the shop floor. The manufacturing process influences how the dispatch list is created. Contrary to the literature presuming that APS systems are most suitable in job shop processes, it is found that the manufacturing process is not a crucial factor when deciding whether APS systems are an appropriate investment. It is found that the level of data quality needed in the APS system depends to a large extent on how the dispatch list is used. For example, is the dispatch list used as a guideline, not a regulation, the need for accurate data in the module is reduced. This article extends the previous literature concerning APS systems by analysing how APS systems influence PAC as a whole and increase the understanding of the challenges of using APS systems in PAC
The Potential of Improving Construction Transport Time Efficiency—A Freight Forwarder Perspective
No full textConstruction transport, in general, is not carried out efficiently, resulting in unnecessary costs and CO2 emissions. Although it has been found that there is a great potential to improve construction transport, little research has been conducted within this field. The purpose of this study is to contribute to the construction transport time efficiency by identifying non-value-adding activities and their causes from a freight forwarder perspective. A single case study was conducted and two flows, a goods delivery flow and a waste material flow, were mapped and analyzed with the help of value stream mapping (VSM). We ran two workshops to discuss the findings of the VSM. The results from this study show that there is large potential for improving construction transport time efficiency as over 40% of the time was used for non-value-adding activities. Although transport suffers from similar non-value-adding activities undertaken in other industries, this study identifies the transport activities with respect to construction transport. The findings further highlight areas of potential improvements, such as improved information sharing, planning, and coordination among all stakeholders. This knowledge can be used by the freight forwarder and the main contractor to improve construction transport time efficiency. The limitation of this study is that it is based on a single case of a freight forwarder. It does not provide a full picture of construction transport efficiency but rather a starting point for future studies
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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