Underground excavations break the balance of the initial stress field and cause stress redistributions in the surrounding rock masses. Problems normally arise as the stress exceeds the rock mass strength. In addition, the rock mass contains preexisting defects, such as the fissures, fractures, joints, faults, shear zones, dikes, etc., which could significantly weaken the rock mass strength and make the rock mass behavior complicated. The stability of underground excavations is of great importance to an operating mine project since it ensures the safety of the working environment and the successful ore exploration. Due to the complex geological conditions and engineering disturbances, the assessment of rock mass stability for a practical engineering problem is extremely challenging and difficult, which needs to be solved by the modern numerical methods. In this dissertation, the rock mass stability around tunnels in an underground mine in the USA was investigated by performing three-dimensional modeling using the 3DEC 3-Dimensional Distinct Element Code. Comprehensive stress analyses were respectively carried out on a preliminary model and a more advanced model. In the preliminary study, the built model contains the inclined lithologies, a non-persistent fault, and a convoluted tunnel system. The geomechanical property values used for the rock masses and discontinuities in the numerical model were estimated using the available geotechnical information and the experience of the research group. The Mohr-Coulomb and strain softening constitutive relations were prescribed for the rock masses; the coulomb slip joint model was assigned for the discontinuities. The influence of the boundary conditions, block constitutive models, horizontal in situ stress and rock support system on the tunnel stability was investigated. The rock mass behavior was quantified using the results of stress, displacement, and yielded zones around the tunnels. It showed that the roller boundary conditions resulted in slightly different but comparable results with the combined boundary conditions (roller and stress combined) where K0 equals to 0.4 or 0.5. Whereas the in-situ stress field for a complex geological system can only be obtained by applying proper boundary stresses and then by performing stress analysis. The softening behavior of the rock masses caused more deformations and yielded zones around the tunnels; the rock masses around the tunnels were observed to reach the residual strength values, which can be treated as failed areas. In addition, the M-C and s-s rock masses reacted differently as the K0 value changed. At K0=1.0, the tunnels seemed to be the most stable; K0=1.5, however, provided the worst scenario with roof and floor problems. With respect to the effectiveness of the support system, a large amount of the bonds of the supports was failing, thus, the deformations and yielded zones around the tunnels were slightly improved. Finally, comparisons between the numerical modeling results and the field measurements implied the applicability of strain softening behavior and a K0 value between 0.5 and 1.0 for the mine. Based on the specific geological, geotechnical, and construction information, a numerical model incorporating accurate features was developed. It includes a non-planar, weak interlayer, the persistent and non-persistent faults, and the open and backfilled excavations. The mechanical property values used for the rock masses and faults were estimated based on the laboratory test results of the intact rock and smooth joints. The strain softening behavior was specified for the rock masses belonging to the average quality, and the rock masses that reached residual strengths were assumed to be failing. The linear relations between the fault stiffnesses and normal stress were described using the continuously yielding joint model. To simulate the mine construction process in the field, the sequential excavation, backfilling, and supporting procedures were numerically implemented; additionally, a novel routine was applied to account for the delayed installation of the supports. Results showed that the tunnels close to the fault and the backfilled area were less stable. Most of the displacements around the tunnels occurred within a distance of zero to 2 or 3 m from the tunnel surface. The varying K0 value caused great changes in the rock mass behavior and the shear behavior of the major fault; significant instability of the tunnels was triggered by the high horizontal in situ stress. Parametric studies on the rock mass condition, rock mass residual strengths, and fault property values showed that the tunnel stability was more sensitive to the former two factors than the last one. A systematic investigation was conducted to evaluate the current rock supports installed at the mine where the increasing stress relaxation was incorporated. The deformations and of the failure zone thicknesses around the tunnels were reduced up to 8% and 20% after applying the supports instantaneously, and the reductions were improved by the delayed installation of supports. Additionally, the safety of supports was evaluated by the bond shear and bolt tensile failures, which was also improved with incorporation of delayed supporting. It was found that the current rock supports are insufficient in length, bond and tensile strengths. Therefore, a stronger support system was suggested. The stronger supports worked better in stabilizing the tunnels. Based on the deformations and failures of the rock masses, the length of the bolts on walls was suggested to be 4-5 m. At the end, the horizontal convergence strain predicted by the numerical simulations were calculated at two locations where the tape extensometers were installed. Good agreements with the field measurements were obtained for the cases that have the average rock mass properties and K0 values in the range 0.5-1.25.

This thesis describes design of Simulator FM-CW range finders. It is choosing the optimal method of realization and inform about basic properties of continuous working radar. The work includes an analysis of errors in real rangefinder and a numerical estimate of the maximum error in real devices. Contains detailed block diagram of simulator FM-CW range-finder and computer simulation of function generator frequency modulated signal, demodulator. Further work includes the complete construction documents for the preparation and implementation of basic functional verification

Megatrends such as globalization, digitalization and the increased rate of technological   developmentare all example of aspects that directly affect and challenge companies. While it opens up for new business opportunities it also serves an increasingly competitive climate and puts tougher pressure on organizations. While several traditional management models are focused on internal aspects such as improving processes, reducing waste and removing non-value adding procedures it is argued in literature that having dynamic capabilities is key to succeed in a more rapidly changing environment. This means being able to not only handle daily business but also to sense, shape and seize opportunities and transform the organization accordingly. The Silicon Valley Model (SVM) is a holistic management model that aims at generating dynamic capabilities for firms in rapidly changing environments. This study is centered on identifying if the five principles that constitute the SVM are adopted in large multinational Swedish companies founded during the industrial era. The five principles are: 1. The Dynamic Firm 2. A People-Centric Approach 3. An Ambidextrous Organization 4. An Open Organization That Networks with Its Surroundings 5. A Systems Approach By interviewing 14 C-level employees in Telia, Lantmännen, Trelleborg and “Company A” we found that Telia and Lantmännen have implemented or have clear transformation initiatives that indicate that they are moving towards implementing all the management principles of the SVM. Trelleborg have or are moving towards all principles except an ambidextrous organization, which was not found during interviews. The fourth case company is anonymous and therefore called Company A. They  are operating in a more stable environment, which moves towards being more dynamic. They was seen implementing some management principles of the model, but did not have a holistic approach for it. The common denominator is that all companies come from having established satisfyingly efficient operational cores and profitability levels, before shifting focus towards having a growth and innovation focus. / Megatrender som globalisering, digitalisering och den ökade takten på teknologisk utveckling är allaaspekter som direkt påverkar och utmanar företag. Medan det öppnar upp för nya affärsmöjligheter  så bidrar det också till ökad konkurrens och större press på företags organisationer. Medan flera traditionella ledningsmodeller är fokuserade på interna aspekter såsom att förbättra processer, minska slöseri och ta bort icke värde-adderande processer, hävdas dynamiska förmågor vara en nyckel till att lyckas i en mer snabbrörlig omgivning. Detta innebär att man inte bara hanterar sin dagliga verksamhet utan också känner av och tar till vara på möjligheter samt förändrar sin organisation i enlighet med dessa. Silicon Valley Modellen (SVM) är en holistisk företagsledningsmodell som ämnar generera dynamiska förmågor för företag i snabbrörliga omgivningar, med syfte att skapa innovation och tillväxt. Den här studien är centrerad kring att identifiera om de fem principer som utgör SVM är anammade i stora multinationella svenska företag som är grundade under den industriella eran. De fem principerna är: 1. Den Dynamiska Firman 2. Individen i Centrum 3. Både-och-Organisation 4. Öppenhet och Nätverkande med Omvärlden 5. Systemansats Genom 14 C-level intervjuer på Telia, Lantmännen, Trelleborg och “Company A” drogs slutsatsen  att Telia och Lantmännen har implementerat eller har klara transformationsinitiativ som indikerar på att de rör sig mot att implementera hela SVM. Trelleborg rör sig mot att täcka hela, förutom både-och- organisation som inte hittades under intervjuerna. Det fjärde företaget, anonymt kallat Company A, verkar i en mer stabil tillverkningsindustri men rör sig mot en mer rörlig omgivning. De sågs implementera några principer från modellen, men ansågs inte ha ett holistiskt närmande till SVM. Den gemensamma nämnaren är att de fyra företagen kommer från att ha etablerat tillfredställande effektiva kärnverksamheter och lönsamhetsnivåer innan de skiftat fokus mot tillväxt och innovation.

With energy demands at an all time high, mechanical power systems are under great scrutiny. Substantial efforts are being made throughout the world to reduce energy use in common mechanical systems such as the internal combustion engine and transmission system. Eliminating or reducing efficiency losses in the transmission is a potential source of improving the efficiency of the system. To do so, various alternative types of transmissions are being investigated. At Brigham Young University, development of a Positively Engaged Continuously Variable Transmission (PECVT) is progressing. In addition to the efficiency increases that would occur as a result of operating the engine at a more constant speed, a PECVT type transmission may reduce efficiency losses that occur in a standard transmission by eliminating the disengagement of involute gear sets to change gear ratios of the transmission. For a PECVT, this is done by maintaining engagement of the input and output members of the transmission, while changing the gear ratio. Both of these types of losses are major contributing factors to the overall efficiency of the transmission and engine system, thus a PECVT is of great interest. The investigation for developing a feasible PECVT began with the identification of a behavioral issue identified in all known PECVT embodiments. This behavioral issue, known as the Non-Integer-Tooth-Problem (NITP), is due to the geometry of an involute gear and prevents specific gear ratios from being achieved. The research effort presented in this thesis returns to the conceptual design of a PECVT to address involutometry along with the NITP. A design tool entitled the Line-of-Action Model is developed which assists in quantifying how a conceptual solution can address the NITP using involutometry principles. As a result of the Line-of-Action Model, the Hybrid Involute Profile was discovered. Due to the simplicity of The Hybrid Involute Profile, it has proven to be an elegant solution to the NITP. Validation of the Hybrid Involute Profile concept was conducted to ensure that this concept satisfies the objectives and requirements of a PECVT and solves the NITP. The validation was completed using two case studies and a theoretical analysis. As a result of the validation, the Hybrid Involute Profile is declared a conceptual principal solution to the NITP. Fulfillment of the PECVT objectives, requirements list and elimination of the NITP by the Hybrid Involute Profile is also demonstrated. With the Hybrid Involute Profile as the conceptual principle solution, the development of a commercially viable PECVT is believed to be attainable.

Thesis (MScEng (Civil Engineering))--University of Stellenbosch, 2011. / ENGLISH ABSTRACT: The southbound screener lane of the Heidelberg Traffic Control Centre received structural improvements by means of an ultra thin continuously reinforced concrete pavement (UTCRCP) overlay. This experimental overlay forms part of the South African National Roads Agency Limited’s innovative highway repair strategy on existing pavements that have exceeded design life. The primary objective of this study was to characterize the UTCRCP overlay with regard to crack spacing formation under accelerated pavement testing (APT). Characterization comprised of empirical modelling techniques, statistical analysis, non destructive testing and software simulations. Pavement deflection responses were empirically and linear elastically converted to input parameters. These parameters were used in the mean crack spacing prediction model of the Mechanistic-Empirical Pavement Design Guide (M-E PDG). Observed cracking under APT was recorded and analyzed by means of descriptive statistics. The outcome of the M-E PDG’s mean crack spacing and the statistics of the observed cracking were evaluated against cncPave simulations. Initial shrinkage crack formations ranged from 500 mm to 900 mm, with a mean spacing of 695 mm. Subsequent secondary cracking reduced the segments, delineated by initial cracking, to intervals consisting of 100 mm to 350 mm. A statistical analysis of the observed cracking indicated that traffic had little effect on the transverse crack spacing formation. The observed cracks yielded a mean spacing of 296 mm, compared to the 186 mm of the M-E PDG mean crack spacing calculation. cncPave simulations indicated that the expected range of cracking would fall between 237 mm and 350 mm with a probability of 50% that crack spacing would exceed 265 mm. The 50th percentile of the observed cracks resulted in a spacing of 233 mm. The APT project was limited to a single test section. No pavement failures occurred during the APT project. A total of 2.8 million 80 kN load repetitions were applied to the UTCRCP. However circular crack formations regarded as a punchout development have formed on the UTCRCP test section. Circular cracks formed around weaknesses in the pavement system. The prediction of these punchout formations incorporates the mean crack spacing result. Occurrence of mean crack spacing forms part of a crack spacing distribution defined by a range. Therefore designing a punchout prediction model for UTCRCP should include the characteristics and range of the crack pattern and not merely the mean crack spacing value. Key Words: UTCRCP, APT, Mean Crack Spacing, Punchout, Descriptive Statistics, cncPave, M-E PDG, Transverse Cracks, Dense Liquid Foundation, Elastic Solid Foundation. / AFRIKAANSE OPSOMMING: Die suidwaartse moniteerings laan van die Heidelberg Verkeersbeheer Sentrum, het strukturele verbetering ondergaan deur die konstruksie van ‘n ultradun aaneen-gewapende betonplaveisel (UDAGBP) wat dien as ‘n deklaag. Hierdie eksperimentele deklaag is deel van die Suid-Afrikaanse Nasionale Paaie Aggentskap Beperk (SANRAL) se vernuftige deurpadherstelstrategie vir bestaande deurpaaie waarvan die ontwerplewe verstryk het. Die primêre doel van hierdie studie is om die UDAGBP te karakteriseer, met betrekking tot kraakspasiëring, deur middel van Versnelde Plaveisel Toetsing (VPT). Die karakteriseringsproses het bestaan uit empiriese moduleringstegnieke, statistiese ontleding, nie-destruktiewe toetsmetodologieë en sagtewaresimulasies. Die plaveiseldefleksiegedrag is empiries en linieêr elasties ontleed en omgeskakel na invoerparameters. Hierdie parameters is gebruik in die peilingsmodel vir gemiddelde kraakspasiëring van die Meganisties-Empiries Plaveisel Ontwerpsgids (M-E POG). Waargenome kraakspasiëring na die afloop van VPT is opgeteken en deur middel van beskrywende statistiek ontleed. Die resultate van die M-E POG se gemiddelde kraakspasiëring en die statistiese ontleding van die waargenome krake is geëvalueer teenoor cncPave simulasies. Aanvanklike krimpingskrake het gevorm met wisselende kraakspasiëring tussen 500 mm en 900 mm met ‘n gemiddelde spasiëring van 695 mm. Daaropvolgende krake het die aanvanklike segmente, wat gevorm het tydens die aanvanklike krimpingskrake, verkort na intervalle van 100 mm tot 350 mm. ‘n Statistiese ontleding van die waargeneemde krake het aangedui dat verkeer weinig ‘n aandeel het in die dwarskraak-vormingsproses. Die waargenome krake het ‘n gemiddelde spasiëring van 296 mm in vergelyking met 186 mm van die M-E POG se gemiddelde kraakspasiëring berekening. cncPave simulasies het aangedui dat die verwagte kraakspasiëringsgrense tussen 237 mm en 350 mm is en ‘n 50% waarskynlikheid dat die kraakspasiëring meer as 265 mm is. Die VPT projek is beperk tot ‘n enkele toetsseksie. Geen plaveiselfalings is waargeneem gedurende die VPT projek nie. In totaal was 2.8 miljoen as-lasherhalings aangewend op die UDAGBP. Daar het egeter sirkelvormige kraakformasies, wat beskou word as ponsswigting, ontwikkel op die UDAGBP toetsseksie. Sirkelvormige kraakpatrone het gevorm rondom swak plekke in die plaveisel. Die peilingsmodelle van hierdie ponsswigting maak gebruik van die gimiddelde kraakspasiëringsresultaat. Die verskynsel van gemiddelde kraakspasiëring in hierdie studie is deel van ‘n kraakspasiëringsverdeling, gedefinieerd deur ‘n spasiëringsgrens. Daarom moet die kraakspasiëringskarakteristieke en spasiëringsgrense in ag geneem word in die ontwerpsproses van ‘n UDAGBP ponsswigting-peilings-model, nie slegs die waarde van die gemiddelde kraakspasiëring nie. Sleutel woorde: UDAGBP, VPT, Gemiddelde Kraakspasiëring, Ponsswigting, Beskrywende Statistiek, cncPave, M-E POG, Transversale Krake, Digte Vloeistof Fondasie, Elasties- Soliede Fondasie.

Research hypothesis The dependence of maximal and submaximal indices of aerobic fitness and cardio respiratory system function on the type of ergometry will change due to specific impact of slow adaptation of the researched athletes. The functional indices of persons of different athletic fitness and sports specialization responsible for general adaptation of the human body to physical loads should vary less performing different continuously increasing loads or constant physical loads compared to those fitness indices which more depend on the adaptation specificity of trained muscles. The aim of the research was to establish the peculiarities of indices of athletes’ aerobic fitness and cardio respiratory system function in dependence on ergometry and the specificity of slow adaptation. Research objectives: 1. To compare maximal and submaximal values of indices of cardio respiratory system function of swimmers and untrained persons during cycling and arm ergometry. 2. To compare maximal values of indices of cardio respiratory system function of athletes in dependence on ergometry and the specificity of slow adaptation. 3. To compare submaximal values of indices of cardio respiratory system function of athletes in dependence on ergometry and the specificity of slow adaptation. 4. To compare the changes in the indices of cardio respiratory system function of athletes in the transitional phases of different constant physical load in dependence on ergometry and the specificity of... [to full text] / Tyrimo hipotezė. Maksimalių ir submaksimalių aerobinio pajėgumo ir vegetacinių sistemų funkcijos rodiklių priklausomumas nuo ergometrijos pobūdžio pakis dėl specifinio tiriamų sportininkų lėtos adaptacijos poveikio. Skirtingo treniruotumo ir sportinės specializacijos asmenų organizmo funkcijos rodikliai, atsakingi už bendrąją organizmo adaptaciją fiziniams krūviams, turėtų mažiau skirtis atliekant skirtingo pobūdžio nuosekliai didinamus ar pastovius fizinius krūvius, negu tie pajėgumo rodikliai, kurie labiau priklauso nuo treniruojamų raumenų adaptacijos specifikos. Tyrimo tikslas - nustatyti sportininkų aerobinio pajėgumo ir vegetacinių sistemų funkcijos rodiklių ypatumus priklausomai nuo ergometrijos ir lėtosios adaptacijos specifikos. Tyrimo uždaviniai: 1. Palyginti plaukikų ir nesportuojančių asmenų maksimalias ir submaksimalias vegetacinių sistemų funkcijos rodiklių reikšmes įvairaus pobūdžio darbe. 2. Palyginti sportininkų maksimalias vegetacinių sistemų funkcijos rodiklių reikšmes įvairaus pobūdžio darbe priklausomai nuo ergometrijos ir lėtosios adaptacijos specifikos. 3. Palyginti sportininkų submaksimalias vegetacinių sistemų funkcijos rodiklių reikšmes įvairaus pobūdžio darbe priklausomai nuo ergometrijos ir lėtosios adaptacijos specifikos. 4. Palyginti sportininkų vegetacinių sistemų funkcijos rodiklių kaitą pereinamosiose pastovaus intensyvumo įvairaus pobūdžio darbo fazėse priklausomai nuo ergometrijos ir lėtosios adaptacijos specifikos. Tyrimo rezultatų... [toliau žr. visą tekstą]

Os primeiros estudos sobre pavimentos de concreto continuamente armados (PCCA) foram desenvolvidos em zonas cujo clima característico é o temperado (EUA, Holanda e Bélgica), não se tendo estudos técnicos acerca do comportamento do pavimento em ambiente tropical. A premissa de funcionamento do PCCA está baseada na não execução de juntas de retração, obrigatórias em pavimentos de concreto simples (PCS), ou seja, as fissuras devido à retração do concreto ocorrem aleatoriamente, sendo controladas pela elevada taxa de armadura longitudinal disposta longitudinalmente ao longo de toda a extensão do pavimento. Como essa armadura não possui função estrutural, pois é colocada acima da linha neutra da placa, no banzo comprimido, sua função é manter as fissuras fortemente apertadas, garantindo suavidade ao rolamento e elevada transferência de carga (LTE), a qual ocorre pelo intertravamento dos agregados nas faces fissuradas, proporcionando assim um pavimento de alta durabilidade e que dispende baixíssimos custos com manutenção. No Brasil, a primeira experiência com PCCA teve início no ano de 2010, quando foram construídas quatro seções de 50 m de extensão cada, consideradas curtas em comparação aos 400 m de extensão de um PCCA rodoviário que podem ser alcançados ao final de um dia de trabalho. O monitoramento contínuo de tais seções mostrou haver uma diferença muito significativa de comportamento, comparado aos PCCA tradicionais, no que tange o tempo decorrido para estabelecimento do padrão de fissuração (a primeira fissura surgiu um ano após a construção), bem como espaçamento médio entre as fissuras, devido à curta extensão das placas e a inexistência de um sistema de ancoragem nas extremidades. Assim, para melhor compreender o comportamento de pavimentos de concreto com armadura contínua com padrões condizentes à realidade rodoviária em ambiente tropical, em janeiro de 2016, foi construído no campus da Universidade de São Paulo o primeiro PCCA de longa extensão do Brasil, com 200 m de comprimento. Foram empregados quatro diferentes tipos de concreto, variando o tipo de cimento e o tipo de agregado, bem como foram empregados aço galvanizado e aço comum. Para entender o comportamento do pavimento sob as condições climáticas brasileiras foram realizados três estudos: levantamento de fissuras (espaçamento e abertura), modelagem analítica do espaçamento entre fissuras através de modelos de previsão de retração em concreto e testes com FWD para avaliação da eficiência de transferência de carga (LTE) entre as fissuras. A análise do padrão de fissuração mostrou que o desenvolvimento das fissuras aconteceu conforme a literatura técnica, tendo início na primeira semana após a concretagem e atingindo aproximadamente 60% do número total de fissuras antes do primeiro mês. As seções centrais possuem o maior número de fissuras, pois estão ancoradas pelas seções de extremidade, onde o surgimento das fissuras é mais lento por conta da falta de ancoragem. As aberturas das fissuras mostraram-se maiores nas posições com aço galvanizado devido à menor aderência aço-concreto nesse caso, em comparação às posições com aço comum. O modelo de previsão de retração no concreto que melhor se aproximou do espaçamento médio desenvolvido em campo foi o modelo do Eurocode 2, com diferenças em torno de 30%, aproximadamente. As análises de LTE mostraram um desempenho muito satisfatório, apesar de a LTE nas regiões com aço galvanizado ter resultado menor do que a LTE nas regiões com aço comum. / The first studies on continuously reinforced concrete pavements (CRCP) were developed in areas in which the typical weather is temperate (United States, Netherlands and Belgium), with no technical studies carried out in tropical weather. CRCP structural premise is based on a slab without construction joints which are required in jointed plain concrete pavements (JPCP); i.e., CRCP cracks due to concrete shrinkage occur randomly being controlled by the high longitudinal reinforcement percentage, positioned longitudinally along the pavement length. As the longitudinal reinforcement has no structural role, because it is placed above the slab neutral axis, in the compression zone, its main function is to keep cracks strongly tight, ensuring a smooth ride and high load efficiency transfer (LTE) at cracks, which occurs through aggregates interlocking, thereby providing a highly durable pavement with low maintenance costs. The first experience with CRCP in Brazil started in 2010, when four experimental sections were constructed. Each section is 50 meters long, short when compared to the traditional CRCP that can extend for over 400 meters providing that concrete pouring does not stop. Continuous monitoring of these sections has shown that the short CRCP behaves differently from traditional CRCP, regarding the time taken for the cracking pattern full development (the first crack was visible on the surface one year after the construction), as well as average cracking space due to the slab\'s short extension and lack of anchorage. Therefore, in order to fully analyze the behavior of a traditional CRCP under tropical weather, in January 2016, the first long extension CRCP in Brazil was built, at the University of São Paulo campus, with 200 meters length. Four types of concrete were applied in the construction, varying cement and aggregate type. Galvanized and ordinary steel were used as well. To analyze the pavement behavior under Brazilian climatic conditions, three studies were carried out: cracks surveys (spacing and width), analytical modeling crack spacing through shrinkage prediction models and Falling Weight Deflectometer testing to evaluate the crack\'s load transfer efficiency (LTE). Cracking pattern analysis has shown cracks development consistent with technical literature. The first cracks appeared during the first week after concrete placement and, before the first month, about 60% of the total cracks number had developed. Central sections presented greatest number of cracks as they are anchored by the outer sections, where cracking occurs slower due to the lack of anchorage. Cracks width was higher in areas with galvanized steel due to the weaker steel-concrete bond, when compared to areas with common steel. The shrinkage prediction model for concrete that better approached the average field crack spacing was the Eurocode 2, with mean difference of 30%. LTE analysis has shown a quite satisfactory performance, even though LTE in areas with galvanized steel is lower than LTE in areas with common steel.

Made available in DSpace on 2016-04-04T18:32:32Z (GMT). No. of bitstreams: 1 Raquel Abrahao.pdf: 588284 bytes, checksum: b5ce52b515f60b0320ad6d7f5b4040b7 (MD5) Previous issue date: 2006-06-19 / At the beginning of this century we lived a sparkle of social transformation, politics, educational and paragon transformation. In face to this scenery the needs of lecturers that knows how to brave the countless contradictions lived in classrooms harmonized with very well founded work with theoretically basis becomes indispensable for a meaningful pedagogic practice. Addressing this purpose, the Sao Paulo State Educational Office (SEE) gave priority, among their responsibilities, to the continuously development of their professionals, being such program the matter of our research which investigates the continuously formation program named TEIA DO SABER UNIVERSIDADES from Jos? Bonif?cio Teaching Directory (specifically the Reading and Learning course). Our objective is to perceive the judgment of teachers from the Public System from Jos? Bonif?cio Teaching Directory about the real contribution of the continuously formation program TEIA DO SABER with related its instructive work, as well as identifying if the proposed ends by the Educational Office were accomplished. The documental analysis of Decentralized Actions Basic Project from TEIA DO SABER Program and semi-structured interviews with the teachers establishes the resources we picked up to answer our research objectives. Our work meet in Superior Teaching area and research line, teaching of evaluation and meeting two category of analysis: a) Continuously Development: conceptions in construction and the TEIA DO SABER and b) Articulations and disarticulations of TEIA DO SABER. In our regiounal, seem to reinforce a reprodutivist perspective that theachers are considerat as mere executors of bureau oractics task feeding the hateful capitalisa logic, inattentive from their reality. Without preoccupation with a continuously develop- ment that leads teachers to get a critical understanding of the pedagogical reality with over coming possibilities, the program TEIA DO SABER appears consolidadte with a continuously politicies that teachers, in yours speeches, appears private appropriation itself to be insert in educational ranking . / Neste in?cio de s?culo, vivemos um borbulhar de transforma??es sociais, pol?ticas, educacionais, paradigm?ticas. Frente a esse panorama, a necessidade de docentes que saibam enfrentar as in?meras contradi??es vividas nas salas de aula aliadas a um trabalho alicer?ado com fundamenta??es te?ricas, torna-se imprescind?vel para uma pr?tica pedag?gica significativa. Para tanto, a Secretaria da Educa??o do Estado de S?o Paulo (SEE) priorizou, entre suas a??es, a forma??o continuada de seus profissionais, a qual ? objeto da nossa pesquisa que investiga o programa de forma??o continuada da SEE TEIA DO SABER UNIVERSIDADES da Diretoria de Ensino de Jos? Bonif?cio (especificamente o curso Ler e Aprender). Nosso objetivo ? o de conhecer a opini?o dos professores da rede p?blica estadual da Diretoria de Ensino de Jos? Bonif?cio, sobre a contribui??o efetiva do programa em rela??o ? seu trabalho docente, como tamb?m, identificar se as finalidades propostas pela secretaria foram atingidas. A an?lise documental do Projeto B?sico das A??es descentralizadas do PROGRAMA TEIA DO SABER e entrevistas semi-estruturadas junto aos professores s?o os recursos que elegemos para responder aos nossos objetivos. Este trabalho encontra-se na ?rea de Ensino Superior e linha de pesquisa Ensino em Avalia??o e as an?lises se apoiaram em duas categorias: a) Forma??o Continuada: concep??es e o TEIA DO SABER; b) Articula??es e desarticula??es do TEIA DO SABER. Os resultados revelam que o PROGRAMA TEIA DO SABER, em nossa regional, parece refor?ar uma perspectiva reprodutivista em que professores s?o considerados como meros executores de tarefas burocr?ticas para alimentar a nefasta l?gica capitalista, alheios ? pr?pria realidade. Sem a preocupa??o de uma forma??o continuada que os levem a fazer uma leitura cr?tica da realidade pedag?gica, com possibilidades de supera??o, o programa TEIA DO SABER parece alicer?ar-se a uma pol?tica de forma??o que refor?a a cultura da certifica??o de compet?ncias. Cultura, esta, que os professores, em seus discursos, transparecem a apropria??o privada da mesma para estarem inseridos no ranking educacional.

The research presented in this thesis regards walking of quadruped robots, and particularly the walking of the Warp1 robot. The motivation for the robot is to provide a platform for autonomous walking in rough terrain. The thesis contains six papers ranging from development tools to actuation of robot legs. The first paper describes the methods and tools made for control development. These tools feature: programming of the robot without low level coding (C-code); that the controller has to be built only once for simulation and experiments; and that names of variables and constants are unchanged through the chain of software Maple -- Matlab -- Simulink -- Real~Time~Workshop -- xPC--Target. Three controllers, each making the robot walk are presented. The first controller makes the robot walk using the crawl gait. The method uses static stability as method for keeping balance and the instantaneous trunk motions are given by a concept using the so called weight ratios. A method for planning new footholds based on the positions of the existing footholds is also proposed and the controller experimentally verified. The second walking controller shows that the robot also can walk dynamically using the trot gait. The method proposed uses information from ground contact sensors on the feet as input to control balance, instead of, which is common, inertial sensors. It is experimentally verified that Warp1 can trot from level ground onto a slope and turn around while staying balanced. The main ideas of these two walking controllers are fused in the third which enables smooth transitions between crawl and trot. The idea of using the ground contact sensors from the first controller is here used to estimate the position of the center of mass. This controller uses weight ratios in the gait crawl as well as in the dynamic gait trot. Hence, the method of using weight ratios is not only useful for static stability for which it was originally intended. The controller is experimentally verified on Warp1. The Warp1 robot weighs about 60 kg, has 0.6 m long legs with three actuated joints on each. The speed and strength is sufficient only for slow walking, even though the installed power indicates that it should be enough for faster walking. The reason is that a walking robot often needs to be strong but slow when the feet are on the ground and the opposite when in the air. This can not be achieved with the motors and transmissions currently used. A transmission called the passively variable transmission (PVT) is proposed which enhance motor capabilities of robot joints. It is elastic, nonlinear and conservative. Some general properties for elastic transmissions are derived such that they can be compared with conventional transmissions. The PVT gives strong actuation at large loads and fast actuation at small loads. The proposed transmission is compared to a conventional transmission for a specific task, and the result is that a smaller motor can be used. / QC 20100831

In this research, the four valve independent metering configuration is to be investigated. The Independent metering concept will be emphasized and compared to spool valve coupled metering conventional technologies. Research focuses on the energy savings potential of the four valve independent metering configuration in addition to improving performance. The basic model of interest in this research is an actuator that is controlled by the four valve independent metering configuration to move beam like members of mobile hydraulic equipment such as tractor loader backhoes, excavators, and telehandlers. Five distinct (or discrete) metering modes that exist in the literature are initially studied: Powered Extension, High Side Regeneration Extension, Low Side Regeneration Extension, Powered Retraction, and Low Side Regeneration Retraction. The energy saving potential of these modes is studied and comparisons between this system and a conventional spool valve controlled actuator are conducted. The problem of switching between these five modes is treated as an optimal control problem of a switched dynamic system. Before solving the optimal control problem, a dynamic model for the system of interest is first derived. The model is experimentally validated. General theory for the optimal control problem is derived and then applied to the hydraulic system of interest. The results are then interpreted and explained by looking into the force-speed capability of modes. The effect of mode switching on system performance is studied as well. The basic mechanical system used for this analysis is a continuous rotating beam that undergoes structural vibrations due to mode switching in the driving hydraulic actuator. A fully coupled actuator-beam model is investigated. A non-dimensional analysis is pursued to generalize the study results. The optimal switching analysis and the vibrational study lead to the idea of Continuously Variable Modes (CVMs). Instead of having five distinct modes that determines the flow path by opening two of the four valves in the assembly, three Continuously Variable Modes are presented as an alternative way of controlling the four-valve configuration. These three CVMs combine the distinct modes and use three of the four valves to provide the fluid flow path. The five distinct modes become a special case of these three CVMs. It is going to be shown that CVMs have more force-speed capabilities than the distinct modes and provide for better velocity and vibrational performance by virtue of always offering a continuous flow path. The theory behind CVMs is presented and experimental validation follows.