This study aimed to identify the causes of significant problems existing in the metallurgical sector, and a solution is proposed for the setup process. We detail the theoretical background of the processes in the lean manufacturing methodology, which will be applied to a rolling machine. Further, we provide a brief description of the company and the sector’s problems. We describe success stories of companies that implemented various lean manufacturing tools. We also present some of the results achieved across sectors to gain an in-depth understanding of the technique and a practical support of the implemented model. Our proposal is based on the lean manufacturing methodology; tools such as Single Minute Exchanges of Dies, Kaizen, 5S, and value stream mapping (VSM) will be used to reduce setup times and to impact machine layout and productivity positively. We also show the implementation results of a pilot plan conducted in the company over a period of more than 3 months. / Revisión por pares

An important characteristic of all systems is availability. Availability is the probability that a system or piece of equipment will operate in a prescribed manner when used under specified conditions. It is primarily a design dependent parameter. Availability derives from a systems reliability and maintainability. Reliability is the probability that a system will operate for a specified time under specified operating conditions. It is commonly measured by the mean-time-between-failure (MTBF). Maintainability is the ability of a system to be maintained. For this report, maintainability is measured by the mean maintenance down time (MDT). The MDT is a function of several variables, including the mean-time-to-repair (MTIR) and Logistics Delay Time (LDT). MTIR is the time that active maintenance is being performed. The LDT is the time delay due to spare part availability, transportation, repair facility availability, traveling to the location of the malfunction, etc. LDT is a major portion of the MDT. In order to meet a requirement of improved system availability, the MTBF and/or the MDT must be improved. Decreasing the distance between the repair organization and the location of the failure may have a significant impact on LDT, assuming that the system's LDT is positively correlated to the distance traveled. An improvement in the LDT corresponds to an improvement in the MDT, hence the availability. For a situation where the repair function (referred to as the repair unit) travels to the location of the failed component, the deployment location may have a critical impact on a system's availability. In a system where the operating components are located over a wide area and the repair organization must travel to the component to effect a repair, there are numerous ways to deploy the servicing units. The systems maintenance concept addresses this issue. The deployment of the repair units is the central focus of this report. / Master of Science

The research is based on the problems encountered in the production process of companies in the metalworking sector. The problem arises from the low availability of machines in the production process due to working conditions (39.5%), poor maintenance management (40.3%) and poor-quality control (20.2%) that generate low profitability for business. As a solution, Lean Manufacturing tools are implemented to improve the process and increase profitability. The improvement proposal consists of a series of stages: first, the definition of indicators for the measurement of the variables; then, the design and implementation of a pilot in the production process and, in parallel, a simulation system will be designed to evaluate the long-term results. The document concludes that the implementation of the proposed tools will increase the availability of machines and an OEE to 55%, avoiding defective products and reducing reprocessed products by 4%.

A methodology to estimate stochastic surface water flows was developed and applied to a case study area using chance constrained programming model. The results were analyzed as to the effects on different areas of production in Utah.

Doctor Educationis / As the world moves into a hyper-connected global society with near universal access to the internet, cybercrime has become a global challenge. The problems embedded in the issue of cybercrime are at least twofold. Firstly, the proliferation of cybercrime globally, and more specifically in South Africa, is outstripping the pace at which governments and lawmakers are able to respond efficiently. Secondly, where governments do manage to respond, there is a temptation to do so on the basis of a superficial understanding of the essence of cybercrime. There are many debates about the novelty of cybercrime in which participants have described it as “old wine in new skin”. This study takes the position that cybercrime is neither completely novel nor is it merely a virtual manifestation of the ordinary terrestrial crimes. The premise of this research is that cybercrime is an interesting and unique form of criminality that manifests itself in a number of challenging ways. These manifestations need to be considered independently and comprehensively if effective countermeasures are to be devised. This is not to say that every single offence has to be considered critically. That would be impracticable. It would suffice that certain types of cybercrimes be classified differently from other types, so as not to paint all with the same brush.

Many ecological and evolutionary processes have been described underlying natural selection but supporting evidence in wild settings is often lacking and our understanding remains incomplete. Using a multi-scale approach, I investigated expression of facultative den behavior (denning) among and within ursid species. Among species, lack of denning behavior was supported by relaxation of selection pressures of seasonal food availability due to realization of two sources of ecological opportunity; colonization of new habitat and adaptation of key innovations. Of denning species, I found evidence of adaptive ecological plasticity in den chronology among and within populations consistent with relaxed selective pressures influencing seasonal food availability and energetic budgets. I supported these finding using indices of fitness and established ecological theory. Further knowledge of organismal response to selection pressures has practical applications in predicting responses to novel and fluctuating pressures and aids in our understanding of the complexities of ecology and evolution.

Very few studies have explored the relationship between the availability of certain types of firearms and gun density on both gun aggravated assaults and gun homicides. Nonetheless, research by Koper (2001) discovered that the availability of more lethal types of firearms, not gun density, was directly related to an increase in gun homicide rates for Dallas. However, this study did not take into account certain social and economic variables that may strengthen or weaken the determined relationship. The current study uses data previously analyzed by Koper (2001) and includes social and economic variables that have been linked to lethal violence while using gun aggravated assaults and gun homicides as the dependent variables. The results will help ascertain to what extent the impact of firearm availability on gun crimes is contingent on contextual factors.

Bottomland hardwood stands managed as greentree reservoirs (GTRs) provide critical habitat for numerous wildlife species. The oak component in GTRs is of critical importance to wildlife managers since oaks produce high energy foods during the winter. However, GTR management warrants concern since it has been linked to increased mortality and insufficient regeneration of desirable species. This project evaluates willow oak acorn production and the effects of flooding and midstory control on the survival and growth of planted willow oak seedlings. Winter flooding reduced survival of seedlings inundated in early October but did not reduce survival of seedlings inundated in mid-November. Midstory control did not produce desired light levels for the future survival of underplanted seedlings. Acorn production was good for both years. Trees with DBH between 55 and 65 cm produced the majority of sound acorns. Acorn production was likely adequate to support foraging waterfowl and natural regeneration.

The impacts of the introduction of casino gambling in Plainville, MA and surrounding communities are of interest in developing informed policy. Problem gambling is a public health issue as associated harms include physical and mental illness, impaired relationships with one’s close social network, impacts on school or work, financial difficulties and illegal behavior. The results of surveys prior to and after the introduction of the casino were used to evaluate potential differences in the prevalence of at-risk and problem gambling, associations amongst health and gambling behavior covariates with at-risk and problem gambling status by year, and changes of covariate relationships with at-risk and problem gambling between years (2014 Total n = 1,090; 2016 Total n = 999; Total N = 2,089). No change in prevalence of at-risk and problem gambling was observed. A borderline significant higher rate in casino gambling between survey years was observed for at-risk and problem gamblers. Future research should aim to explore the influence of gambling availability on vulnerable subgroups of the population to create fully informed policy.

Selection research often examines whether adverse impact can be reduced/eliminated from employment practices. Such research, however, largely ignores the influence of minority availability issues (i.e., the number of minorities who apply and the number of minorities who accept a job offer); three general factors comprise minority availability: the missing applicant problem, targeted recruitment and job refusal rates. As minority availability issues have not been systematically addressed in the broader literature, the purpose of this study was twofold: 1) to highlight the importance of and explicate a comprehensive description of their potential effects on adverse impact and 2) to demonstrate such effects through monte carlo simulations. Specifically, simulations were used to examine issues related to the level effects and covariance effects of minority availability on adverse impact. Therefore, an iterative process was used whereby minority availability factors were manipulated to produce combinations that meaningfully affect adverse impact; the goal was to conduct as many simulations as necessary to establish a reliable pattern of the effects of minority availability on adverse impact. Simulation results suggest minority availability issues can influence the detection of adverse impact. In fact, minority availability issues may hinder efforts to reduce adverse impact in some selection contexts. Implications of these results are discussed. / Ph. D.