Rutting-induced permeability loss of open graded friction course mixtures

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.

Vacuum brazing of alumina ceramic to titanium for biomedical implants using pure gold as the filler metal

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.^

Factors influencing the implementation of substance use prevention programs in elementary schools

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.^

Regulating Casino Gaming: A Checklist for States Considering It

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.

Família e escola: memórias de letramento

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.

Família e escola: memórias de letramento

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.

Transformational learning-environments in the post-secondary classroom: through the experience of indigenous women

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.

Ruote per arredi da ufficio dal design innovativo

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.

Retificação plana tangencial dos ferros fundidos nodular, vermicular e cinzento em várias condições de corte

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.

MIDIATIZAÇÃO E CIRCULAÇÃO DE SENTIDOS NAS MANIFESTAÇÕES DE JUNHO DE 2013

Os sistemas comunicacionais têm presenciado alterações expressivas desde a chegada da internet, onde os dispositivos participativos crescem a cada dia, fruto do processo cada vez mais evidente de uma sociedade midiatizada. O trabalho aborda o tema das Manifestações de Junho, ocorridas no Brasil, busca evidenciar os tensionamentos do discurso da grande imprensa frente a cobertura da mídia alternativa, reflete quais foram os desdobramentos de uma das principais manifestações que o país já presenciou e analisa a circulação de sentidos nos eventos ocorridos em 2013. Para tanto, combina uma pesquisa bibliográfica e histórica com pesquisa empírica voltada à análise de narrativas das colunas do jornalista Arnaldo Jabor para a Rádio CBN, durante as manifestações, como também de dois comentários em vídeo de Jabor, para o Jornal da Globo, da TV Globo. E para evidenciar o referencial teórico da presente pesquisa, analisou-se um terceiro vídeo, que tem como título “La Hipocresia de los Medios”, fruto da edição do programa Bajada de Línea, da TV Argentina, que repercute as falas de Arnaldo Jabor, transforma-se literalmente em uma terceira fala, evidenciando a mudança de opinião e confirmando que a midiatização afeta o modelo clássico de comunicação.

Active Energy: Three Mills - open workshop

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.

The LiDAR Compass: Extremely Lightweight Heading Estimation with Axis Maps

This paper introduces the LiDAR compass, a bounded and extremely lightweight heading estimation technique that combines a two-dimensional laser scanner and axis maps, which represent the orientations of flat surfaces in the environment. Although suitable for a variety of indoor and outdoor environments, the LiDAR compass is especially useful for embedded and real-time applications requiring low computational overhead. For example, when combined with a sensor that can measure translation (e.g., wheel encoders) the LiDAR compass can be used to yield accurate, lightweight, and very easily implementable localization that requires no prior mapping phase. The utility of using the LiDAR compass as part of a localization algorithm was tested on a widely-available open-source data set, an indoor environment, and a larger-scale outdoor environment. In all cases, it was shown that the growth in heading error was bounded, which significantly reduced the position error to less than 1% of the distance travelled.

Performance and Assessment of Rehabilitated Steel Culverts

This thesis explores the effects of rehabilitation on the structural performance of corrugated steel culverts. A full-scale laboratory experiment investigated the effects of grouted slip-liners on the performance of two buried circular corrugated steel culverts. One culvert was slip-lined and grouted using low strength grout, while the other was slip-lined and grouted using high strength grout. The performances of the culverts were measured before and after rehabilitation under service loads using single wheel pair loading at 0.45m of cover. Then, the rehabilitated culverts were loaded to their ultimate limit states. Results showed that the low and high strength grouted slip-liners provided strength well beyond requirements, with the low strength specimen failing at a load 2.4 times the fully factored service load, while the high strength specimen did not reach an ultimate limit state before bearing failure of the soil stopped testing. Results also showed that the low strength specimen behaved rigidly under service loads and flexibly under higher loads, while the high strength specimen behaved rigidly under all loads. A second full-scale experiment investigated the effect of a paved invert rehabilitation procedure on the performance of a deteriorated horizontal ellipse culvert. The performance of the culvert before and after rehabilitation was examined under service loads using tandem axle loading at 0.45m of cover. The rehabilitated culvert was then loaded up to its ultimate limit state. The culvert failed due to the formation of a plastic hinge at the West shoulder, while the paved invert cracked at the invert. Results showed that the rehabilitation increased the structural performance of the culvert, increasing the system stiffness and reducing average strains and local bending at critical locations in the culvert under service loads. A sustainability rating tool specifically for the evaluation of deteriorated culvert replacement or rehabilitation projects was also developed. A module for an existing tool, called GoldSET, was created and tested using two case studies, each comparing the replacement of a culvert using a traditional open-cut method with two trenchless rehabilitation techniques. In each case, the analyses showed that the trenchless techniques were the better alternatives in terms of sustainability.

Standardization in the Pre-Columbian Pottery from El Caño, Panama: Specialization, Productivity and Consumption

The pottery found in the burials of El Cano is uniform in style to these made in the coclesanos valleys between 700 and 1000 AD. The coefficient of variability of the different pottery forms, evidence diverse standardizations values for polychrome and non-polychrome ceramics. Moreover, data of funerary contexts from the Cano recently excavated, suggest that elite has controlled ceramic production. This control over the production of certain goods reveals that these were important in the support or proper operational of the chiefdoms in Panama and mark the phase of splendour of this culture.

Investigation of the Impact of Dual-Lane Axle Spacing on Lateral Load Distribution, 2016

The spacing of adjacent wheel lines of dual-lane loads induces different lateral live load distributions on bridges, which cannot be determined using the current American Association of State Highway and Transportation Officials (AASHTO) Load and Resistance Factor Design (LRFD) or Load Factor Design (LFD) equations for vehicles with standard axle configurations. Current Iowa law requires dual-lane loads to meet a five-foot requirement, the adequacy of which needs to be verified. To improve the state policy and AASHTO code specifications, it is necessary to understand the actual effects of wheel-line spacing on lateral load distribution. The main objective of this research was to investigate the impact of the wheel-line spacing of dual-lane loads on the lateral load distribution on bridges. To achieve this objective, a numerical evaluation using two-dimensional linear elastic finite element (FE) models was performed. For simulation purposes, 20 prestressed-concrete bridges, 20 steel bridges, and 20 slab bridges were randomly sampled from the Iowa bridge database. Based on the FE results, the load distribution factors (LDFs) of the concrete and steel bridges and the equivalent lengths of the slab bridges were derived. To investigate the variations of LDFs, a total of 22 types of single-axle four-wheel-line dual-lane loads were taken into account with configurations consisting of combinations of various interior and exterior wheel-line spacing. The corresponding moment and shear LDFs and equivalent widths were also derived using the AASHTO equations and the adequacy of the Iowa DOT five-foot requirement was evaluated. Finally, the axle weight limits per lane for different dual-lane load types were further calculated and recommended to complement the current Iowa Department of Transportation (DOT) policy and AASHTO code specifications.