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The challenge of persistent appearance-based navigation and mapping is to develop an autonomous robotic vision system that can simultaneously localize, map and navigate over the lifetime of the robot. However, the computation time and memory requirements of current appearance-based methods typically scale not only with the size of the environment but also with the operation time of the platform; also, repeated revisits to locations will develop multiple competing representations which reduce recall performance. In this paper we present a solution to the persistent localization, mapping and global path planning problem in the context of a delivery robot in an office environment over a one-week period. Using a graphical appearance-based SLAM algorithm, CAT-Graph, we demonstrate constant time and memory loop closure detection with minimal degradation during repeated revisits to locations, along with topological path planning that improves over time without using a global metric representation. We compare the localization performance of CAT-Graph to openFABMAP, an appearance-only SLAM algorithm, and the path planning performance to occupancy-grid based metric SLAM. We discuss the limitations of the algorithm with regard to environment change over time and illustrate how the topological graph representation can be coupled with local movement behaviors for persistent autonomous robot navigation.

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Eco-driving instructions could reduce fuel consumption to up to 20% (EcoMove, 2010). Participants (N=13) drove an instrumented vehicle (i.e. Toyota Camry 2007) with an automatic transmission. Fuel consumption of the participants were compared before and after they received eco-driving instructions. Participants drove the same vehicle on the same urban route under similar traffic conditions. Results show that, on free flow sections of the track, all participants drove slightly faster (on average, 0.7 Km/h faster), during the lap for which they were instructed to drive in an eco-friendly manner as compared to when they were not given the eco-driving instruction. Suprisingly, eco-driving instructions increased the RPM significantly in most cases. Fuel consumption slightly decreased (6%) after the eco-driving instructions. We have found strong evidence showing that the fuel saving observed in our experiment (urban environment, automatic transmission) fall short of the 20% reduction claimed in other international trials.

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Currently, finite element analyses are usually done by means of commercial software tools. Accuracy of analysis and computational time are two important factors in efficiency of these tools. This paper studies the effective parameters in computational time and accuracy of finite element analyses performed by ANSYS and provides the guidelines for the users of this software whenever they us this software for study on deformation of orthopedic bone plates or study on similar cases. It is not a fundamental scientific study and only shares the findings of the authors about structural analysis by means of ANSYS workbench. It gives an idea to the readers about improving the performance of the software and avoiding the traps. The solutions provided in this paper are not the only possible solutions of the problems and in similar cases there are other solutions which are not given in this paper. The parameters of solution method, material model, geometric model, mesh configuration, number of the analysis steps, program controlled parameters and computer settings are discussed through thoroughly in this paper.

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In Australia, collaborative contracts, and in particular, project alliances, have been increasingly used to govern infrastructure projects. These contracts use formal and informal governance mechanisms to manage the delivery of infrastructure projects. Formal mechanisms such as financial risk sharing are specified in the contract, while informal mechanisms such as integrated teams are not. Given that the literature contains a multiplicity of often untestable definitions, this paper reports on a review of the literature to operationalize the concepts of formal and informal governance. This work is the first phase of a study that will examine the optimal balance of formal and informal governance structures. Desk-top review of leading journals in the areas of construction management and business management, as well as recent government documents and industry guidelines, was undertaken to to conceptualise and operationalize formal and informal governance mechanisms. The study primarily draws on transaction-cost economics (e.g. Williamson 1979; Williamson 1991), relational contract theory (Feinman 2000; Macneil 2000) and social psychology theory (e.g. Gulati 1995). Content analysis of the literature was undertaken to identify key governance mechanisms. Content analysis is a commonly used methodology in the social sciences area. It provides rich data through the systematic and objective review of literature (Krippendorff 2004). NVivo 9, a qualitative data analysis software package, was used to assist in this process. A previous study by the authors identified that formal governance mechanisms can be classified into seven measurable categories: (1) negotiated cost, (2) competitive cost, (3) commercial framework, (4) risk and reward sharing, (5) qualitative performance, (6) collaborative multi-party agreement, and (7) early contractor involvement. Similarly, informal governance mechanisms can be classified into four measureable categories: (1) leadership structure, (2) integrated team, (3) team workshops, and (4) joint management system. This paper explores and further defines the key operational characteristics of each mechanism category, highlighting its impact on value for money in alliance project delivery. The paper’s contribution is that it provides the basis for future research to compare the impact of a range of individual mechanisms within each category, as a means of improving the performance of construction projects.

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This study sets out to provide new information about the interaction between abstract religious ideas and actual acts of violence in the early crusading movement. The sources are asked, whether such a concept as religious violence can be sorted out as an independent or distinguishable source of aggression at the moment of actual bloodshed. The analysis concentrates on the practitioners of sacred violence, crusaders and their mental processing of the use of violence, the concept of the violent act, and the set of values and attitudes defining this concept. The scope of the study, the early crusade movement, covers the period from late 1080 s to the crusader conquest of Jerusalem in 15 July 1099. The research has been carried out by contextual reading of relevant sources. Eyewitness reports will be compared with texts that were produced by ecclesiastics in Europe. Critical reading of the texts reveals both connecting ideas and interesting differences between them. The sources share a positive attitude towards crusading, and have principally been written to propagate the crusade institution and find new recruits. The emphasis of the study is on the interpretation of images: the sources are not asked what really happened in chronological order, but what the crusader understanding of the reality was like. Fictional material can be even more crucial for the understanding of the crusading mentality. Crusader sources from around the turn of the twelfth century accept violent encounters with non-Christians on the grounds of external hostility directed towards the Christian community. The enemies of Christendom can be identified with either non-Christians living outside the Christian society (Muslims), non-Christians living within the Christian society (Jews) or Christian heretics. Western Christians are described as both victims and avengers of the surrounding forces of diabolical evil. Although the ideal of universal Christianity and gradual eradication of the non-Christian is present, the practical means of achieving a united Christendom are not discussed. The objective of crusader violence was thus entirely Christian: the punishment of the wicked and the restoration of Christian morals and the divine order. Meanwhile, the means used to achieve these objectives were not. Given the scarcity of written regulations concerning the use of force in bello, perceptions concerning the practical use of violence were drawn from a multitude of notions comprising an adaptable network of secular and ecclesiastical, pre-Christian and Christian traditions. Though essentially ideological and often religious in character, the early crusader concept of the practise of violence was not exclusively rooted in Christian thought. The main conclusion of the study is that there existed a definable crusader ideology of the use of force by 1100. The crusader image of violence involved several levels of thought. Predominantly, violence indicates a means of achieving higher spiritual rewards; eternal salvation and immortal glory.

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This research is based on the problems in secondary school algebra I have noticed in my own work as a teacher of mathematics. Algebra does not touch the pupil, it remains knowledge that is not used or tested. Furthermore the performance level in algebra is quite low. This study presents a model for 7th grade algebra instruction in order to make algebra more natural and useful to students. I refer to the instruction model as the Idea-based Algebra (IDEAA). The basic ideas of this IDEAA model are 1) to combine children's own informal mathematics with scientific mathematics ("math math") and 2) to structure algebra content as a "map of big ideas", not as a traditional sequence of powers, polynomials, equations, and word problems. This research project is a kind of design process or design research. As such, this project has three, intertwined goals: research, design and pedagogical practice. I also assume three roles. As a researcher, I want to learn about learning and school algebra, its problems and possibilities. As a designer, I use research in the intervention to develop a shared artefact, the instruction model. In addition, I want to improve the practice through intervention and research. A design research like this is quite challenging. Its goals and means are intertwined and change in the research process. Theory emerges from the inquiry; it is not given a priori. The aim to improve instruction is normative, as one should take into account what "good" means in school algebra. An important part of my study is to work out these paradigmatic questions. The result of the study is threefold. The main result is the instruction model designed in the study. The second result is the theory that is developed of the teaching, learning and algebra. The third result is knowledge of the design process. The instruction model (IDEAA) is connected to four main features of good algebra education: 1) the situationality of learning, 2) learning as knowledge building, in which natural language and intuitive thinking work as "intermediaries", 3) the emergence and diversity of algebra, and 4) the development of high performance skills at any stage of instruction.

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Purpose The purpose of this paper is to reduce the potential for litigation by improving valuers’ awareness of water risks. As part of a valuer’s due diligence, the paper provides guidance as to how to identify such risks by explaining the different types and examining how online search tools can be used in conjunction with more traditional methods to evaluate the probability of these risks occurring. Design/methodology/approach The paper builds on prior research, which examined the impact of water to and for valuations. By means of legal/doctrinal analysis, this paper considers relevant issues from the perspective of managing client expectations and needs. In so doing it identifies online tools available to assist in identifying at risk properties and better informing clients. Findings While the internet provides a variety of tools to gain access to relevant information, this information most commonly is only provided subject to disclaimer. Valuers need to ensure that blind reliance is not given to use of these tools but that the tools are used in conjunction with individual property inspections. Research limitations/implications Although the examples considered primarily are Australian, increasing water risks generally make the issues considered relevant for any jurisdiction. The research will be of particular interests to practitioners in coastal or riverine areas. Practical implications Valuation reports are sought for a variety of purposes from a variety of clients. These range from the experienced, knowledgeable developer looking to maximise available equity to the inexperienced, uneducated individual looking to acquire their home and thinking more often than not with their heart not their head. More informed practices by valuers will lead to valuation reports being more easily understood by clients, thus lessening the likelihood of litigation against the valuer for negligence. Originality/value The paper highlights the issue of water risks; the need for valuers to properly address potential and actual risks in their reports; and the corresponding need to undertake all appropriate searches and enquiries of the property to be valued. It reinforces the importance of access to the internet as a tool in the valuation process.

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In this paper the soft lunar landing with minimum fuel expenditure is formulated as a nonlinear optimal guidance problem. The realization of pinpoint soft landing with terminal velocity and position constraints is achieved using Model Predictive Static Programming (MPSP). The high accuracy of the terminal conditions is ensured as the formulation of the MPSP inherently poses final conditions as a set of hard constraints. The computational efficiency and fast convergence make the MPSP preferable for fixed final time onboard optimal guidance algorithm. It has also been observed that the minimum fuel requirement strongly depends on the choice of the final time (a critical point that is not given due importance in many literature). Hence, to optimally select the final time, a neural network is used to learn the mapping between various initial conditions in the domain of interest and the corresponding optimal flight time. To generate the training data set, the optimal final time is computed offline using a gradient based optimization technique. The effectiveness of the proposed method is demonstrated with rigorous simulation results.

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Total world fishery production 1995, including aquaculture, of fish, shellfish, frogs and turtles – reached a new record of 112.9 million tones live weight. Marine fishery had a share of 91,9 million tonnes (+ 0.4) and freshwater fishery 21.0 million tonnes (+ 2.0). Not included in these figures are seals, whales, crocodiles and algae. Marine mammals and crocodiles are listed by number of killed individuals, and not given by weight. Algae alone represent a biomass of 7.1 million tonnes, but are not included by the FAO in the nominal „total production of the world“ either. About two thirds of the marine fishery harvest was used for human consumption, one third for industrial purposes – mainly production of fish meal and fish oil.

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Studies on Hymenopteran Parasitism of Drosophila

Flies of the genus Drosophila are subject to attack by a number of parasitic forms. Sturtevant (1921) has listed records of parasitism by protozoa (Leptomonas), fungi (Muiaria and Stigmatomyces), nematodes, mites and v~rious hymenoptera. According to Sturtevant, Perkins (1913) has bred at least five species of hymenoptera, belonging to the proctotrupoid, cynipoid and chalcidoid groups, upon Drosophiline flies. H.S. Smith has bred an unidentified proctotrupoid and a chalcidoid, Pachy crepoideus dubius Ashmead* from both Drosophila melanogaster ani D. hydei. Kieffer ( 1913) has described three species of hymenoptera from Africa collected by Silvestri and stated by him to be parasitic on Drosophila, species not given. They are Trichopria (Planopria) rhopalica (Diapriidae), Ashmeadopria drosophilae (Diapriidae), and the insect which forms the subject matter of the present investigation, Eucoila drosophilae (Figitidae).

There are in addition a number of predacious enemies among wasps, spiders, flies and beetles.

The present account is concerned with parasitism of various species of Drosophila by Eucoila drosophilae Kieff. The wasps were found b y Dr. w. P. Spencer who exposed traps in an effort to collect Drosophila at Long Lake, Ohio, in Sept. 1934 . Drosophila larvae from the trap gave a large number of pupae from which wasps emerged in considerable proportions. Since that time stock s have been maintained in culture on Drosophila melanogaster.

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[eus] Gaur egungo eskoletan, oraindik ere, zoritxarrez, behar besteko garrantzirik ematen ez zaion eta sendotu behar den ikasleen autoezagutza fisikoaren inguruan, honako landa-lana diseinatu eta ikasleekin burutu egin da, hauengan aldaketa bat sortarazteko asmoarekin. Horretarako, prestatutako ariketa desberdinen bitartez, ikasleen arrazonamendu maila, baita maila emozionala ere landu egin da. Kontuan izanda, autoezagutzan, aldaketak epe luzean ematen direla, esku-hartze honen bidez ez dira aldaketa handirik edo esanguratsurik nabarmendu. Dena den, errespetuaren balorea ikasleengan transmititzea lortu egin da. Hori dela eta, landa lana burutu eta gero, egindakoaren inguruan, autokritika egin da.

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A água é um bem essencial a todos os seres vivos. Porém, o homem não tem dado o valor e atenção necessários para a preservação dessa riqueza. Por mais que o ser humano não faça a água desaparecer do planeta, ele tem contribuído e muito para o decréscimo de sua qualidade. Dentre as várias atividades antropogênicas, que tem contribuído para a poluição das águas, destaca-se a atividade industrial. A indústria têxtil, por exemplo, libera enormes volumes de dejetos, destacando-se os corantes, além deles prejudicarem a ocorrência de fotossíntese, apresentam elevada toxicidade ao meio marinho. Com isso, este trabalho visa estudar a degradação do corante Alaranjado de Metila via catálise heterogênea. Neste estudo, foram realizadas a preparação e a caracterização de partículas metálicas estabilizadas em sílica, sendo essas partículas com diferentes teores de ferro (50 %wt, 25 %wt e 5 %wt) aderido ao suporte. Após o preparo dos catalisadores realizou-se o estudo de sua eficiência frente a diferentes parâmetros como: quantidade de catalisador, temperatura e pH. Por meio dos testes realizados foi possível observar que a quantidade do catalisador influência a reação de redução do corante Alaranjado de Metila. Porém, quando se atinge o ponto de saturação, mesmo que se adicione mais catalisador não é possível aumentar a degradação. Através da variação da temperatura, observou-se que quanto maior a temperatura maior a degradação do corante. Isso pode ser explicado devido o aumento do número de colisões entre os sítios ativos do catalisador e as moléculas do corante. E por meio da variação de pH, concluiu-se que pHs ácidos permitem que a reação de redução do corante ocorra mais rápido e pHs elevados tornam a reação de degradação do corante mais lenta, porém ainda assim ocorrem de forma satisfatória. O catalisador pôde ser reutilizado por até 3 vezes, sem nenhum tratamento prévio. Os catalisadores a 50 %wt, assim como, a 25 %wt foram capazes de degradar o corante de forma eficiente, porém o catalisador a 5 %wt não se mostrou ser eficaz. Foram realizados testes sob radiação microondas e a reação de redução ocorreu de forma muito eficaz, apresentando 100% de degradação em apenas 2 minutos. Além disso, realizou-se o estudo cinético, onde segundo dados experimentais, as reações foram classificadas como sendo de primeira ordem

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Este estudo procura compreender como os detentos elaboram a vida cotidiana na prisão e, em que medida o acesso aos dispositivos da educação e da religião disponíveis no cárcere podem contribuir para a reintegração social do indivíduo recluso. A pesquisa foi desenvolvida na perspectiva de que a população carcerária é constituída majoritariamente de pessoas marcadas pela vulnerabilidade social e que não tiveram acesso aos direitos fundamentais ao exercício da cidadania. Para estes indivíduos, o espaço escolar é percebido como espaço de sociabilidade e também de oportunidade de mudança, uma vez que, possibilita vislumbrar caminhos alternativos à vida criminal. As observações foram realizadas em quatro escolas localizadas em unidades prisionais do Rio de Janeiro. Trata-se de um estudo de caráter etnográfico que utiliza a narrativa dos presidiários sobre educação e religião como recurso metodológico. Através de depoimentos e entrevistas, procura identificar experiências que produziram significados no contexto das escolas existentes no interior das prisões e que revelam formas de elaboração da vida cotidiana pelos alunos detentos.

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Wallace, Joanne, et al., 'Body composition and bone mineral density changes during a premier league season as measured by dual-energy X-ray absorptiometry', International Journal of Body Composition Research (2006) 4(2) pp.61-66 RAE2008

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The paper reviews the provisions of the White Book on National Security of the Republic of Poland. It states that the issue of health security is not given adequate significance there. The accessibility of health services is considered, in general, solely in terms of their availability. The assumptions concerning the concept of providing the number of beds required in a state of threat to national security and in time of war do not take into account the current socio-economic conditions and need to be reviewed. The conclusions emphasize the dilemmas that emerge as a result of the unilateral promotion of a single category of national security, that is military security, in the context of ensuring health security.