919 resultados para wheel


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This research paper presents an examination of the journey to and from crime for autotheft offenders in the UK. For 852 offences, ‘wheel’ distances are calculated for triangles formed by offenders’ home location, theft location, and vehicle disposal location. The study demonstrates typical isosceles mobility triangles; distances travelled to and from home locations are roughly equal, whereas distances between theft and disposal points were shorter. Distances travelled by offenders under 17 years old and offences involving drug and drink were shown to be shorter than comparison groups. Prolifi c offenders tend to travel further, although there is signifi cant variation in this subgroup. Explanations and implications are discussed.

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This paper addresses the question of how just-in-time can be implemented within high variety manufacture. To illustrate some of the principles in relation to the high variety-low volume situation the case of a computer manufacturer is considered in detail. For contrast the paper also considers the case of the manufacture of highly-configured four wheel drive vehicles where both variety and volumes are high. The most important issue in high variety/low volume production is that JIT operation should be seen in terms of the tactical holding of inventory in upstream buffers within the supply chain so that value is not added to work in progress prematurely. Tactical buffers ensure that service levels are maintained and the risk of stock-outs is minimized. In high variety/high volume production schedule integrity is the key factor, unreliable schedules being a major inhibitor to the introduction of JIT.

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Automated negotiation is widely applied in various domains. However, the development of such systems is a complex knowledge and software engineering task. So, a methodology there will be helpful. Unfortunately, none of existing methodologies can offer sufficient, detailed support for such system development. To remove this limitation, this paper develops a new methodology made up of: (1) a generic framework (architectural pattern) for the main task, and (2) a library of modular and reusable design pattern (templates) of subtasks. Thus, it is much easier to build a negotiating agent by assembling these standardised components rather than reinventing the wheel each time. Moreover, since these patterns are identified from a wide variety of existing negotiating agents (especially high impact ones), they can also improve the quality of the final systems developed. In addition, our methodology reveals what types of domain knowledge need to be input into the negotiating agents. This in turn provides a basis for developing techniques to acquire the domain knowledge from human users. This is important because negotiation agents act faithfully on the behalf of their human users and thus the relevant domain knowledge must be acquired from the human users. Finally, our methodology is validated with one high impact system.

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* The research has been partially supported by INFRAWEBS - IST FP62003/IST/2.3.2.3 Research Project No. 511723 and “Technologies of the Information Society for Knowledge Processing and Management” - IIT-BAS Research Project No. 010061.

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A new creep test, Partial Triaxial Test (PTT), was developed to study the permanent deformation properties of asphalt mixtures. The PTT used two duplicate platens whose diameters were smaller than the diameter of the cylindrical asphalt mixtures specimen. One base platen was centrally placed under the specimen and another loading platen was centrally placed on the top surface of the specimen. Then the compressive repeated load was applied on the loading platen and the vertical deformation of the asphalt mixture was recorded in the PTTs. Triaxial repeated load permanent deformation tests (TRT) and PTTs were respectively conducted on AC20 and SMA13 asphalt mixtures at 40°C and 60°C so as to provide the parameters of the creep constitutive relations in the ABAQUS finite element models (FEMs) which were built to simulate the laboratory wheel tracking tests. The real laboratory wheel tracking tests were also conducted on AC20 and SMA13 asphalt mixtures at 40°C and 60°C. Then the calculated rutting depth from the FEMs were compared with the measured rutting depth of the laboratory wheeling tracking tests. Results indicated that PTT was able to characterize the permanent deformation of the asphalt mixtures in laboratory. The rutting depth calculated using the parameters estimated from PTTs' results was closer to and showed better matches with the measured rutting than the rutting depth calculated using the parameters estimated from TRTs' results. Main reason was that PTT could better simulate the changing confinement conditions of asphalt mixtures in the laboratory wheeling tracking tests than the TRT.

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Functionality of an open graded friction course (OGFC) depends on the high interconnected air voids or pores of the OGFC mixture. The authors' previous study indicated that the pores in the OGFC mixture were easily clogged by rutting deformation. Such a deformation-related clogging can cause a significant rutting-induced permeability loss in the OGFC mixture. The objective of this study was to control and reduce the rutting-induced permeability loss of the OGFC based on mixture design and layer thickness. Eight types of the OGFC mixtures with different air void contents, gradations, and nominal maximum aggregate sizes were fabricated in the laboratory. Wheel-tracking rutting tests were conducted on the OGFC slabs to simulate the deformation-related clogging. Permeability tests after different wheel load applications were performed on the rutted OGFC slabs using a falling head permeameter developed in the authors' previous study. The relationships between permeability loss and rutting depth as well as dynamic stability were developed based on the eight OGFC mixtures' test results. The thickness effects of the single-layer and the two-layer OGFC slabs were also discussed in terms of deformation-related clogging and the rutting-induced permeability loss. Results showed that the permeability coefficient decreases linearly with an increasing rutting depth of the OGFC mixtures. Rutting depth was recommended as a design index to control permeability loss of the OGFC mixture rather than the dynamic stability. Permeability loss due to deformation-related clogging can be effectively reduced by using a thicker single-layer OGFC or two-layer OGFC.

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One of the many promising applications of metal/ceramic joining is in biomedical implantable devices. This work is focused on vacuum brazing of C.P titanium to 96% alumina ceramic using pure gold as the filler metal. A novel method of brazing is developed where resistance heating of C.P titanium is done inside a thermal evaporator using a Ta heating electrode. The design of electrode is optimized using Ansys resistive heating simulations. The materials chosen in this study are biocompatible and have prior history in implantable devices approved by FDA. This research is part of Boston Retinal implant project to make a biocompatible implantable device (www.bostonretina.org). ^ Pure gold braze has been used in the construction of single terminal feedthrough in low density hermetic packages utilizing a single platinum pin brazed to an alumina or sapphire ceramic donut (brazed to a titanium case or ferrule for many years in implantable pacemakers. Pure gold (99.99%) brazing of 96% alumina ceramic with CP titanium has been performed and evaluated in this dissertation. Brazing has been done by using electrical resistance heating. The 96% alumina ceramic disk was manufactured by high temperature cofired ceramic (HTCC) processing while the Ti ferrule and gold performs were purchased from outside. Hermetic joints having leak rate of the order of 1.6 × 10-8 atm-cc/ sec on a helium leak detector were measured. ^ Alumina ceramics made by HTCC processing were centreless grounded utilizing 800 grit diamond wheel to provide a smooth surface for sputtering of a thin film of Nb. Since pure alumina demonstrates no adhesion or wetting to gold, an adhesion layer must be used on the alumina surface. Niobium (Nb), Tantalum (Ta) and Tungsten (W) were chosen for evaluation since all are refractory (less dissolution into molten gold), all form stable oxides (necessary for adhesion to alumina) and all are readily thin film deposited as metals. Wetting studies are also performed to determine the wetting angle of pure gold to Ti, Ta, Nb and W substrates. Nano tribological scratch testing of thin film of Nb (which demonstrated the best wetting properties towards gold) on polished 96% alumina ceramic is performed to determine the adhesion strength of thin film to the substrate. The wetting studies also determined the thickness of the intermetallic compounds layers formed between Ti and gold, reaction microstructure and the dissolution of the metal into the molten gold.^

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Prevention scientists have called for more research on the factors affecting the implementation of substance use prevention programs. Given the lack of literature in this area, coupled with evidence that children as early as elementary school engage in substance use, the purpose of this study was to identify the factors that influence the implementation of substance use prevention programs in elementary schools. This study involved a mixed methods approach comprised of a survey and in-person interviews. Sixty-five guidance counselors and teachers completed the survey, and 9 guidance counselors who completed the survey were interviewed individually. Correlation analyses and hierarchical multiple regression were conducted. Quantitative findings revealed ease of implementation most frequently influenced program implementation, followed by beliefs about the program's effectiveness. Qualitative findings showed curriculum modification as an important theme, as well as difficulty of program implementation. The in-person interviews also shed light on three interrelated themes influencing program implementation – The Wheel, time, and scheduling. Results indicate the majority of program providers modified the curriculum in some way. Implications for research, policy, and practice are discussed, and areas for future research are suggested.^

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In his essay - Regulating Casino Gaming: A Checklist for States Considering It – by Leonard E. Goodall, Professor of Management and Public Administration, College of Business and Econornics, University of Nevada, Las Vegas, Professor Goodall initially states: “Since various states are likely to continue to debate the issue of the establishment of legal casinos, and since states considering legal casinos must also decide how best to regulate them, the author discusses the similarities and contrasts in the regulatory systems already in operation.” Certainly not all states have solicited casino gaming, or what people generally refer to as gambling, but many have and the list is growing. If casinos are to be, and indications are that many more states will endorse gaming as a source of revenue, then regulating them must follow as a matter of due course says the author. Keep in mind this essay was written in 1988, and the actuality of casino gaming has indeed come to fruition in many states. “Nevada, having legalized casino gaming in 1931, has over a half-century of experience with the regulatory process,” Professor Goodall informs. “When New Jersey approved the establishment of casinos in Atlantic City in 1976, state officials studied the Nevada system carefully and adopted many of Nevada's procedures.” Professor Goodall bullet-points at least 7 key elements that states wanting to pursue gaming should, or in the cases of Nevada and New Jersey, have already addressed in regard to regulation of the industry. Goodall parses, in more detail, those essentials. The ultimate form of regulation is ownership Goodall says. Either state run, or private are the logical options. “The arguments for private ownership have been both pragmatic and political,” Goodall says. “Legislators, like the general public, are skeptical of the ability of state bureaucracies to run big businesses in an efficient manner. Many of them also believe regulation can be more effective if there is at least an arm's-length distance between regulation and ownership,” the professor opines. Additionally important to consider is the purpose of legalization, says Goodall. Are the proceeds earmarked for general funds, or to be used specifically? Geographic considerations are key, Goodall points out. “This decision will depend partly on a state's reasons for having casinos in the first place,” he expands. “New Jersey's policy, for example, is obviously consistent with its goal of using casinos to reinvigorate Atlantic City.” “In both states, one of the most important functions of the regulatory agencies is that of licensing, the process of investigating individuals or organizations and then authorizing them to participate in the gaming business,” Goodall provides. In closing, Goodall says there is no need for ensuing states to reinvent the wheel when it comes to casino gaming regulation. Nevada and New Jersey already provide two good designs from which to emulate and/or build upon.

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The school has the social function of educating the individual, building knowledge, attitudes and values that make supportive, critical, ethical and participatory. It is understood, however, in this study, these functions will only be, in fact, met at school if the family engagement at school. As a result, the objective of this research is to rescue the stories of families literacies yesterday and today and their expectations forward to school literacy of children. Theoretically, this research is based on studies of literacy (STREET, 1984; KLEIMAN, 1995; TFOUNI, 1995; 2010; OLIVEIRA, 2008) and in research on family literacy (HEATH, 1982; 1983; DANTAS; MANYAK, 2010). Methodologically, it is a qualitative research which fall within the field of Applied Linguistics (MOITA LOPES, 2006), characterized as an approach of the kind interpretative (MAYRING, 2000; CRESWEL, 2010). It takes as research area Municipal School Councilman Jose Sotero - Igapó / Natal-RN, using data generation tools such as: interview, questionnaire, teaching sequence and conversation wheel, aiming to seek answers to the following questions: How important to recover the reading and writing practices of the parents? What are the relationships between the history of the parents and the reading practices prevalent in the family? Which way to articulate these two systems: family and school, giving new meaning to the literacy practices experienced in the family context and the implications of literacy in school literacy of children? From the analysis of the data generated is expected to understand the family-school binomial and its interference in the literacy process of the students.

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The school has the social function of educating the individual, building knowledge, attitudes and values that make supportive, critical, ethical and participatory. It is understood, however, in this study, these functions will only be, in fact, met at school if the family engagement at school. As a result, the objective of this research is to rescue the stories of families literacies yesterday and today and their expectations forward to school literacy of children. Theoretically, this research is based on studies of literacy (STREET, 1984; KLEIMAN, 1995; TFOUNI, 1995; 2010; OLIVEIRA, 2008) and in research on family literacy (HEATH, 1982; 1983; DANTAS; MANYAK, 2010). Methodologically, it is a qualitative research which fall within the field of Applied Linguistics (MOITA LOPES, 2006), characterized as an approach of the kind interpretative (MAYRING, 2000; CRESWEL, 2010). It takes as research area Municipal School Councilman Jose Sotero - Igapó / Natal-RN, using data generation tools such as: interview, questionnaire, teaching sequence and conversation wheel, aiming to seek answers to the following questions: How important to recover the reading and writing practices of the parents? What are the relationships between the history of the parents and the reading practices prevalent in the family? Which way to articulate these two systems: family and school, giving new meaning to the literacy practices experienced in the family context and the implications of literacy in school literacy of children? From the analysis of the data generated is expected to understand the family-school binomial and its interference in the literacy process of the students.

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This study investigated the physical, mental, emotional, and spiritual aspects of transformational learning, including the elements, attributes, factors, and catalysis of the transformational learning environment, as Indigenous women experienced them in the Indigenous Studies 3040H: The Meaning of Work in the Contemporary World (INDG 3040H) course at Trent University. Using a holistic model developed in connection with the Medicine Wheel an Indigenous epistemology is integrated into the study. Qualitative interviews were conducted with eight Indigenous women. The data collected from the interviews indicated that for Indigenous women, the transformational learning environment of the post-secondary classroom is heavily connected to the relationship students develop with themselves, their peers, and the faculty member alongside the content of the course.

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Studio e progettazione di una nuova ruota per arredi da ufficio dal design innovativo. La ruota si differenzia per essere una tipologia Hub-less (senza mozzo), dotata di un carter che la protegge da polveri e corpi esterni e un sistema di riduzione dell'attrito che aiuta l'utente a muoversi in completa libertà.

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In a scenario of increasing competitiveness of the global industrial sector and with a consumer market increasingly demanding, there is an increased demand for new materials and, consequently, possibilities to explore new research and technological advances towards the development of new manufacturing methods or the improvement of existing technologies. In the case of cast irons, new grades of them have been developed so that their mechanical properties have been improved, making them more competitive with steel, expanding the applications and thus represents great economic gain for metallurgy and manufacturing sectors. This increases the interest and creates new opportunities to study these materials and identify how they respond in terms of the surface integrity, tool wear, cutting forces, among others, when machined by grinding operation. In this context, due to the lack of results from grinding of cast irons and studies comparing grindability among several grades of cast irons found in the literature, this work aims to generate scientific and technological contribution to the metallurgical and metal working sector through roughness results (Ra and Rz parameters) and evaluation and analysis of the subsurface integrity of three cast iron grades (gray, compacted graphite and nodular). The machining trials were performed on a surface grinding machine with silicon carbide grinding wheel at different cutting conditions. The input variables were the radial depth of cut (15 and 30 μm), worktable speed, vw (5 and 10 m/min) and the abrasive grain size of the grinding wheel. The results showed that surface roughness increased with the radial depth of cut for all materials tested; and the lowest values were obtained for gray cast iron. Also, roughness was sensitive to variation of worktable speed and the lowest values were obtained after machining with vw = 5 m/min. With respect to the abrasive grain size, as it decreased the roughness values increased to gray and nodular cast iron grades. Furthermore, grinding burns marks were observed on the surfaces of nodular cast iron and compacted graphite iron grades after grinding the smallest grain size, contrary to what is usually reported in literature. However, no evidence of severe thermal damages below the machined surfaces of all cast iron grades was observed after analyzing the results of hardness and the SEM micrograph images.

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On 14th May, as part of National Mills Weekend, an open workshop was held outside the 18th century House Mill in Bromley by Bow, the world's largest tidal mill. Members of the Geezers Club in Bow worked in the open air with an engineer to construct the stream wheel, which is being developed in ‘flat pack’ format to maximize transferability. The wheel will be installed in the River Lea later this year.