111 research outputs found
Intelligent Simulation Modeling of a Flexible Manufacturing System with Automated Guided Vehicles
Although simulation is a very flexible and cost effective problem solving technique, it has been traditionally limited to building models which are merely descriptive of the system under study. Relatively new approaches combine improvement heuristics and artificial intelligence with simulation to provide prescriptive power in simulation modeling. This study demonstrates the synergy obtained by bringing together the "learning automata theory" and simulation analysis. Intelligent objects are embedded in the simulation model of a Flexible Manufacturing System (FMS), in which Automated Guided Vehicles (AGVs) serve as the material handling system between four unique workcenters. The objective of the study is to find satisfactory AGV routing patterns along available paths to minimize the mean time spent by different kinds of parts in the system. System parameters such as different part routing and processing time requirements, arrivals distribution, number of palettes, available paths between workcenters, number and speed of AGVs can be defined by the user. The network of learning automata acts as the decision maker driving the simulation, and the FMS model acts as the training environment for the automata
network; providing realistic, yet cost-effective and risk-free feedback. Object oriented design and implementation of the simulation model with a process oriented world view, graphical animation and visually interactive simulation (using GUI objects such as windows, menus, dialog boxes; mouse sensitive dynamic automaton trace charts and dynamic graphical statistical monitoring) are other issues dealt with in the study
Air Force Institute of Technology Research Report 2007
This report summarizes the research activities of the Air Force Institute of Technology’s Graduate School of Engineering and Management. It describes research interests and faculty expertise; lists student theses/dissertations; identifies research sponsors and contributions; and outlines the procedures for contacting the school. Included in the report are: faculty publications, conference presentations, consultations, and funded research projects. Research was conducted in the areas of Aeronautical and Astronautical Engineering, Electrical Engineering and Electro-Optics, Computer Engineering and Computer Science, Systems and Engineering Management, Operational Sciences, Mathematics, Statistics and Engineering Physics
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Managerial Problem-Solving Methods and Outline Specification for a Computer-Based Managerial Job-Management System
This thesis examines problem-solving theory and practice by managers and proposes a structure for computer-based job and problem management.
Two principal models are advanced. The Problem-centred model reflects existing perceptions of the problem-solver analysing a specific issue but with further definition given of the main model components. The Role-centred model broadens the perspective to reflect the manager dealing with the totality of his current work units (tasks) amongst which problems form a sub-set. Whilst a work unit may not be 'problematic' it is linked with other issues both in terms of competition for resources and the causal relationships engendered by any resulting actions.
The thesis describes a number of designed methods that have emerged in the last few decades including rational sequential approaches as well as self-contained methods which focus on a particular facet. Whilst the varied nature of most managerial problems precludes the adoption of a rigid phased approach, the individual phase components of the former and the specific foci of the latter may be relevant to some amongst the population of problems. Some of the failures in acceptance of the methods by practitioners can be attributed to an assumption that these are comprehensive rather than selectively relevant. Fieldwork provides additional insights into processes adopted in real-world problem-solving, main findings being fragmentation of a problem into sub-problems, the distinction between processes to solve problems and processes to administer the problem-solving process and the network of relationships between different problems.
The desk-top PC is identified as currently the main tool for managers offering the most significant potential in terms of medium for methods design and delivery. The recently-emerging PIMs systems can provide the basis for job management but the functionality requires substantial expansion to include the problem-centred activities resulting in broad categories termed Search, Input, Output, Holding, Data and Relating. Executive Information Systems and Expert Systems provide increasingly relevant support within this overall framework, along with other tools and techniques.
The main implication of the role-centred model is the requirement that problem-solving methods be embedded within a wider, holistic structure which reflects the manager addressing the totality of his current activities which are prioritised but also interrelated. Within this structure many existing methods, tools and techniques can be assimilated on a non-prescriptive basis as they can be viewed as selectively relevant to types of problem or individual activities within problem-solving processes
Digital watermarking and novel security devices
EThOS - Electronic Theses Online ServiceGBUnited Kingdo
Hot Licks and Rhetoric: Collecting, Community, and Disruptive Literacies
This ethnographic dissertation investigates the activities and tactical technical communications (TTC) of underground music collectors. Through this it explores the concepts of community and institution that compositionists and technical writing scholars use as ways to address social influences on writing, but which fail to explain how these milieus influence the writers and their genres. Collectors of Recordings of Independent Origin (ROIOs), through the use of increasingly disruptive technologies, moved from passive listeners to active producers of music for sharing freely, garnering opposition from the music industry as their activities moved online. This study views the relationship between the music industry, ROIO collectors, and bootleggers through an activity theory lens and applies rhetorical genre analysis to collectors’ voluntary, colloquially written, but highly technical documentation. These methods, coupled with surveys of ROIO collectors, creators, and site administrators, reveal high interactivity and cooperation between these seemingly oppositional groups. By focusing away from social contexts and toward the literacies employed within them and the purposes to which these literacies are applied, this study suggests that the way in which technologies disrupt societies and organizations is analogous to the way in which social contexts influence writing and genre. These findings allow for a more literacy-connected way of seeing institution and a purpose-driven view of community that return analytical focus to writers and the purposes for which write. In turn, these ideas allow us to view tactics, currently viewed in TTC scholarship as opposition to institutional preferences or strategies, in terms of both multiperspectivity of an activity system’s object and the available literacies employed for the writer’s purposes
MANAGING THE UNCERTAINTY ASPECT OF RELIABILITY IN AN ITERATIVE PRODUCT DEVELOPMENT PROCESS
Ph.DNUS-TU/E JOINT PH.D. PROGRAMM
Countertrade as a development tool: a comparative analytical approach
This study explores the consequences of defence countertrade arrangements for national development based on the South African experience in comparative perspective. Although defence countertrade has been controversial in many contexts, it is concluded that it may play a positive developmental role. This is premised on the central role governments can play in ensuring that countertrade's role in national economic development – global pressures and neo-liberalism notwithstanding – remains an important tool through which active industrial policy may be pursued. This can include developing and maintaining a defence industrial base (DIB) in those countries that have such capabilities. Countertrade occurs under two kinds of market conditions. The one is where there is a natural need for trading but it is constrained in some way, for example, by an absence of currency or an oversupply. Under these conditions countries can resort to bartering, which involves a commodity for commodity exchange and no money. The second market condition is one where countertrade is purposefully structured to secure reciprocal benefits as a condition of a commercial sales transaction - defence or civil in nature. This is referred to as leveraged procurement and manifests primarily as defence offsets involving the defence industrial base, which is the concern of this study. Around 40 per cent of countries, including South Africa, use various purposely structured government procurement programmes when procuring goods and services abroad. These programmes apply the principle of reciprocity through the use of internationally accepted countertrade practices that manifest in many diverse ways. Although „countertrade‘ is the collective term, it is regularly referred to as „offsets‘. Procurement leverage is used to secure some reciprocal benefit from the foreign seller (benefits sought vary from country to country). Countertrade-related practices occur widely despite the fact that the World Trade Organisation's (WTO) Agreement on Government Procurement (GPA6) rules out the use of offsets. Their use is viewed as a discriminatory procurement practice that interferes with free trade. However, the WTO allows for exceptions in the case of developing countries and also for national security and public health contracts. It is important to note that countertrade (and offset) practices, valued in billions of US Dollars, are applicable mostly to defence contracts, although becoming increasingly relevant in non-defence (i.e. civil) government procurements. This research systematically interrogated and investigated issues surrounding the origins and subsequent popular and increased use of countertrade since the 1980s. The purported negative impact of defence-related offsets on the defence industrial base (i.e. the loss or gain of jobs, technology and market share) of both the exporting and receiving countries is of particular concern to the US government and the European Union (EU). My exploratory mixed method research, together with practitioner (insider) and reflexive research approaches, culminated in a primarily descriptive, qualitative, analytical narrative. The research is further founded on structured survey questionnaires. These specific research approaches are known to be subjective and biased and I thus needed to take extra care to prevent emotive subjectivities, primarily through triangulating my findings against a variety of other views and arguments pertaining to the research question. This was done to provide for a holistic overview, and in consideration of the case study, in particular. It must be noted that South Africa has two sets of industrial participation policies and practices. One is Defence Industrial Participation (DIP) managed exclusively by Armscor, South Africa's acquisition agency, which favours pursuing defence industry development objectives. The other is the National Industrial Participation Programme (NIPP), managed independently by the Department of Trade and Industry (DTI). The NIPP is primarily focused on the civil industry with a bias towards manufacturing, investments and exports. The DIP is the focus of the case study element of this research. Since its inception in 1968, Armscor has been tasked with establishing a DIB. Until the late 1980s, this DIB made huge strides in developing unique defence equipment to cater for the harsh Southern African environment and its military operational conditions. The DIB's development was enhanced further by the various UN embargoes imposed on the former South African apartheid government. Owing to these embargoes, Armscor dealt with all its defence imports (and exports) in a clandestine manner. Armscor was the only government entity that applied countertrade from around 1988 until 1996 when the DTI introduced NIPP. During the latter part of 1996, Armscor redrafted its countertrade policy with the new DIP policy approved in early 1997. This policy was applied during the biggest arms transaction in South Africa‟s history, namely, the Strategic Defence Package (SDP). A DIP commitment of circa R15 billion resulted from the equipment bought under the SDP. This study investigated how the DIP manifested in practice from 2000 to 2012 within the DIB that involved numerous South African Defence Industry (SADI) entities. The study considered the DIB, its growth and decline, and to what extent the DIP assisted it to retain its capabilities and capacities, including the retention of jobs. Hence, parts of the case study cover issues related to the South African military complex and the SDP‟s selection process. Subsequent investigations into alleged acts of misconduct and maladministration in the selection process, fraud and corruption are also covered, although not in detail, since this matter is sub judice the outcome of the 2011 presidential appointed Arms Procurement Commission (APC) of inquiry that is anticipating completing its investigations in 2015. Although there are many derivative views on the actual defence equipment needs of the South African National Defence Force (SANDF), the study did not endeavour to analyse these views in depth as they are adequately covered in the 1996 Defence Review. Similarly, there are views expressed that South Africa paid much more for its equipment compared with similar types of equipment bought by other countries. A cost comparative analysis was not performed as the exact configuration of each type of equipment can differ substantially due to the unique operational needs of the various defence forces – the exact configuration of such equipment is not in the public domain, since it is a sovereign security concern. Despite many opposing views, it is concluded that DIP (also referred to as defence offsets) has worked for South Africa: in many ways the South African DIP practice compares favourably with internationally accepted best practices. The research‟s postulation that countertrade can be used as a possible development mechanism is therefore supported by the findings of this study that showed that DIP had a positive retention impact on the DIB, and jobs, and made a positive contribution to Gross National Product (GNP7). The study found that the 1997 DIP policy needed to be much better aligned with the broader strategic national industrial development aims and objectives, including better corroboration with the NIPP. In this respect critical inferences are made that the DIP policy primarily focused on the SADI and its capabilities, without considering its wider application in a broader industrial sense. However, in the context of the Armscor legal mandate (i.t.o. Act 57 of 1968) ensuring the establishment of a DIB in South Africa, the DIP policy was clear in its intent to specifically further the interests of only the SADI. However, the 2014 Defence Review recommends that the DIP policy should be much more focused and even prescriptive when considering specific strategic defence needs. Although DIP policy directives contain requirements for establishing strategic local capabilities and capacities that could adequately cater for logistic support, repair and maintenance of foreign produced defence equipment, this aspect was not well contracted in the 1999 SDP. There is also general consensus that foreign obligors should in future not be allowed the freedoms of choice evident in the SDP‟s DIP process, which resulted in numerous smaller companies not benefitting as was generally anticipated. Future defence contracts should not be signed without an appropriate DIP business plan. Hence, all indications are that the DIP regime in South Africa is set to become much more stringent in its application and subsequent discharge administration
CORPORATE SOCIAL RESPONSIBILITY IN ROMANIA
The purpose of this paper is to identify the main opportunities and limitations of corporate social responsibility (CSR). The survey was defined with the aim to involve the highest possible number of relevant CSR topics and give the issue a more wholesome perspective. It provides a basis for further comprehension and deeper analyses of specific CSR areas. The conditions determining the success of CSR in Romania have been defined in the paper on the basis of the previously cumulative knowledge as well as the results of various researches. This paper provides knowledge which may be useful in the programs promoting CSR.Corporate social responsibility, Supportive policies, Romania
Space station systems: A bibliography with indexes (supplement 10)
This bibliography lists 1,422 reports, articles, and other documents introduced into the NASA scientific and technical information system between July 1, 1989 and December 31, 1989. Its purpose is to provide helpful information to researchers, designers and managers engaged in Space Station technology development and mission design. Coverage includes documents that define major systems and subsystems related to structures and dynamic control, electronics and power supplies, propulsion, and payload integration. In addition, orbital construction methods, servicing and support requirements, procedures and operations, and missions for the current and future Space Station are included
Is the Automotive Industry using Design-for-Assembly Anymore?
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