This report is the written part of a bachelorthesis on the computer engineering program at University of Halmstad. The project was a cooperate project that where done together with Free2move Holding AB. Free2move is a company with eight employees in Sweden and four in Malaysia. The company is today developing Bluetooth modules and RFID chips. The market for this kind of products is growing very rapidly, last year it grew 71 percent. The most important market for Free2move is to provide other developers with Bluetooth modules. Free2move has recieved some inquiries from previous customers about a system that would allow communication between two or more persons. After recieving this, Free2move started to evaluate the grounds for such a protocol and also how the transmisison time slots should be distributed among the parties. The result was planned to manage an infinite number of users and the possibility for two users to talk simultaneously. The goal of the project was to develop a prototype of a reciever with functionality according to a specification and protocol developed by Free2move. One part of the project where to do a research of the market to find suitable hardware for the reciever, at least a tranciever/reciever and a processor with DA-converter. Factors such as pricing, power cousumption and size should be take in consideration during the researchphase. Free2move had explicity said that they where intrested in a microprocessor from Texas that had low power comsumption and that we should concider takingthat one. The PIC microprocessor from Micrichip was one of the other candidates. Since the specification of the protocol demanded a DAconverter with 16 bit resouliton an external codec was neccesary to be implemented in to the construction. During the project negotiations about the structure and functionality of the protocol where still not finished. This resulted in a turn in what the goal of this project was, and a new goal where set. The goal where now to develop and construct a reciever and a transmitter and make a research of how well diffrent kind of protocol would perform.

abstract: This dissertation examined sojourner adjustment success utilizing a unique method for collecting and analyzing the perceptions and sense making of the sojourner participants. Although previous research studies in this area have mostly relied on quantitative survey designs and researcher-generated models, this study relied on in-depth, participant-driven, qualitative interviews that were semi-structured using a software-assisted method called Interpretive Structural Modeling (ISM). Through this dissertation research, study abroad students (sojourners) had the opportunity to reflect on their sojourn experience, share their adjustment stories, and identify factors that were personally relevant to their success. This study broke new ground while building on the vast body of work in cross-cultural and sojourner adjustment. Sojourners were asked to provide their perspectives on the relationships among those factors reported in the literature that are commonly believed to influence successful adjustment. This allowed me to connect existing literature on the subject with the lived experience of the sojourner participants. This dissertation sought to answer two research questions. First, what factors do participants identify as being keys to the success of their sojourn? Second, what relationships do participants perceive among the factors contributing to successful sojourner adjustment? This dissertation found that language proficiency played a key role in their adjustment and openness was the factor most selected by participants in their explanation of a successful sojourn. Additionally, participant profiles and influence structure summaries provided evidence of the relationships participants saw among success factors in their lived experiences. In terms of preparing sojourners for going abroad, analysis of the composite structure revealed what could be prioritized in pre-departure training for impending sojourners. Themes emerged which provide insight into the commonalities of the sojourner experience despite differences in one's program or personality. This dissertation also explained additional success factors participants identified (e.g., ability to manage language fatigue, creation of connections with other travelers) that were not initially provided to them. Finally, suggestions for study abroad students/coordinators, researchers, and employers are provided. / Dissertation/Thesis / Ph.D. Communication 2014

A major question in galaxy formation is how the gas supply that fuels activity in galaxies is modulated by their environment. We use spectroscopy of a set of well-characterized clusters and groups at 0.4 < z < 0.8 from the ESO Distant Cluster Survey and compare it to identically selected field galaxies. Our spectroscopy allows us to isolate galaxies that are dominated by old stellar populations. Here we study a stellar-mass-limited sample (log(M*/M-circle dot) > 10.4) of these old galaxies with weak [O II] emission. We use line ratios and compare to studies of local early-type galaxies to conclude that this gas is likely excited by post-AGB stars and hence represents a diffuse gas component in the galaxies. For cluster and group galaxies the fraction with EW([O II]) > 5 angstrom is f([O II]) = 0.08(-0.03)(+0.02) and f([O II]) = 0.06(-0.04)(+0.07), respectively. For field galaxies we find f([O II]) = 0.2 (+0.07)(-0.06), representing a 2.8 sigma difference between the [O II] fractions for old galaxies between the different environments. We conclude that a population of old galaxies in all environments has ionized gas that likely stems from stellar mass loss. In the field galaxies also experience gas accretion from the cosmic web, and in groups and clusters these galaxies have had their gas accretion shut off by their environment. Additionally, galaxies with emission preferentially avoid the virialized region of the cluster in position-velocity space. We discuss the implications of our results, among which is that gas accretion shutoff is likely effective at group halo masses (log M/M-circle dot > 12.8) and that there are likely multiple gas removal processes happening in dense environments.

Este trabalho apresenta o estudo de algumas moléculas do meio interestelar úteis para o levantamento do conteúdo de matéria orgânica do universo e para as condições pré-bióticas na Terra e em outros ambientes no universo. Utilizamos como objeto-teste a Nebulosa Cabeça de Cavalo, devido à sua geometria simples, à sua distância moderada até nós, ao seu campo de radiação ultravioleta bem conhecido resultante da iluminação por uma estrela próxima, $\\sigma$ Orionis, e por ter sido extensivamente estudada por diversos trabalhos. Desse modo, podemos investigar com segurança diversos processos físicos e químicos no meio interestelar. O principal instrumento utilizado neste trabalho foi o código PDR Meudon devido ao fato de que é amplamente utilizado por ser um dos programas de análise de dados de projetos recentes de astronomia, como o projeto Herschel, e por ser público. O código pode ser utilizado para modelizar com confiabilidade a Nebulosa Cabeça de Cavalo, visto que ela mesma é uma PDR (região de fotodissociação) prototípica. Atualizamos o setor de química do código para testar diversos cenários de formação de moléculas. Consideramos o impacto nas abundâncias derivadas das moléculas de várias suposições em relação ao estado do gás (modelos isocórico, isotérmico e isobárico), decidindo em favor de um modelo isobárico. Verificou-se o papel dos raios cósmicos e de vários conjuntos de dados das reações químicas. Obtivemos as abundâncias de várias moléculas, incluindo algumas de potencial importância pré-biótica: CN e seus íons, HCN, HNC, nitrilas e seus íons, hidretos de nitrogênio, benzeno. Investigamos o papel dos ânions e dos PAHs. Finalmente, exploramos canais de produção para heterocíclicos nitrogenados com relevância em astrobiologia: pirrol e piridina. As presentes simulações apresentaram como a exploração de uma pequena gama de possíveis canais de produção de heterocíclicos já resultou em abundâncias significativas para ao menos uma espécie de heterocíclicos nitrogenados, a piridina. Dessa forma, excursões sistemáticas pelos diversos canais de produção deverão revelar mais espécies para serem alvos de buscas. / This work presents the study of some molecules of the interstellar medium that are useful for the bookkeeping of the molecular content of the universe and for prebiotic conditions on Earth and in other environments in the universe. The Horsehead Nebula was chosen as test object, due to its simple geometry, its moderate distance to us, its well-known ultraviolet radiation field resulting from the star $\\sigma$ Orionis, and due the fact that it has been extensively studied in several works. In this way, we can safely investigate several physical and chemical processes on the interstellar medium. The main tool used in the present work was the Meudon PDR code due the fact that it is widely used as one of the legacy data analysis programs of current astronomy projects, e.g. the Herschel project, and it is public. The code can reliably model the Horsehead Nebula, since this nebula is a prototypic PDR (photodissociation region). We updated the chemical sector of the code in order to test several scenarios for molecule production. We considered the impact on the derived molecule abundances of several assumptions relative to the gas state (isochoric, isothermal and isobaric models), and the isobaric model was found to be the most plausible. We checked the role of cosmic rays and several datasets of chemical reactions. We derived the abundances of several molecules, including some of potential prebiotic importance: CN and their ions, HCN, HNC, nitriles and their ions, nitrogen hydrides, and benzene. We investigated the role of anions and PAHs. Finally, we explored production channels for astrobiologically relevant nitrogenated heterocycles: pyrrole and pyridine. This presents simulations show us how the exploration of a small quantities of possibles path of prodution of heterocycles resulted already in significants abundances at least one n-heterocycle specie, the pyridine. Thereby, systemact tours for the many productions paths should show more species to be targe of searches.

The gas kinetic temperature (T-K) of various interstellar environments is often inferred from observations that can deduce level populations of atoms, ions, or molecules using spectral line observations; H I 21 cm is perhaps the most widely used, and has a long history. Usually the H I 21 cm line is assumed to be in thermal equilibrium. and the populations are given by the Boltzmann distribution. A variety of processes, many involving Ly alpha, can affect the 21 cm line. Here we show how this is treated in the spectral simulation code Cloudy, and present numerical simulations of environments where this temperature indicator is used, with a detailed treatment of the physical processes that determine level populations within H-0. We discuss situations where this temperature indicator traces TK, cases where it fails, as well as the effects of Lya pumping on the 21 cm spin temperature. We also show that the Lya excitation temperature rarely traces the gas kinetic temperature.

The aim of this master’s thesis is analysis of wireless communication between mikroprocesors. The first part of the work are analysed the problems the wireless free ISM band. Mainly RFM12B and ZigBee module, which i these band work and ZigBee standart. The second part are described relazation board for both module. Further how programming ZigBee module. And at last programs for tested module.

京都大学 / 0048 / 新制・課程博士 / 博士(理学) / 甲第18073号 / 理博第3951号 / 新制||理||1569(附属図書館) / 30931 / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 鶴 剛, 教授 谷森 達, 教授 柴田 大 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DGAM

The Communications industry is currently involved in a wireless revolution. Consequently, there is a need for a wide variety of wireless solutions to replace existing wired systems. The major systems, such as cellular and satellite, are costly to put in place and require a low BER (bit error rate) to be successful for their real-time applications. In contrast to this are those systems that can tolerate a higher BER as a trade off for cost (<$50.00) and complexity. A typical application for these lower cost systems is monitoring non-critical data that is not required to be delivered real-time. The work presented here focused on designing, building and testing a Proof of Concept Prototype (POCP) for a low-cost wireless data link (WDL). In a typical WDL application, problems arise when too large a data rate attempts to travel the allotted channel bandwidth in the frequency band of interest. Also, limitations imposed by current radio transceiver technology tend to limit WDL design. The existing sponsor's wired system operates at a 9600 Baud, and presented the opposite problem: the data rate was too low for the RF Microdevices RF2905 used for the POCP. This challenge necessitated the development of a low-cost encoding scheme using standard digital logic gates in place of more costly Manchester Encoding. For the digital logic encoding scheme to work, the crystal oscillators had to be modified. This resolved the problem with the low frequency limitations of the RF2905 phase locked-loop. In addition, the polled, asynchronous, and unbalanced RS485 connections of the wired system had to be adapted to interface with the single-ended data connections of the WDL. Finally, the successful design of a timing scheme, using standard TTL components and balanced to unbalanced drivers, resolved the interface problems resulting in a low-cost WDL designed to operate with an existing wired system without requiring modifications to that system. The WDL is transparent in connection and operation and can be inserted without disrupting the current wired system. / Master of Science

Yes / In the modern business era, mobile commerce (m-commerce) is changing the way the business is conducted using the Internet. However, the prominence of m-commerce among small and medium-sized enterprises (SMEs) in the UK is minimal. The purpose of this study is to evaluate the existing literature and to extend the research surrounding the barriers that prevent the adoption of m-commerce amongst SMEs. The study uses an Interpretive Structural Modelling (ISM) and MICMAC approach for guiding and helping managers of SMEs. Data was collected from an expert participant group each of whom had extensive knowledge of m-commerce. The findings represent the unstable nature of variables in the context of their impact on each other, their relationships, and themselves. The listed factors in the proposed framework and the interrelationships between them highlight the multi-dimensional element of m-commerce adoption prevention. This observation proves criticality of analysing data as a collective entity rather than viewing the barriers in isolation. The findings also indicated ‘perceived risk’ being a key barrier that demonstrates how personal opinions of the concept of adoption can have a great significance on the outcome and whether other variables will come into effect.

Massive star formation takes place in the dense cores of molecular clouds where the stars may be obscured at optical wavelengths. An excellent signpost of a massive young stellar object is the presence of an ultra-compact HII region (UCHii), which is a dense photo-ionised cocoon of gas surrounding the newly formed star. The aim of this project is to develop an assembly of numerical tools, caravela, that can simulate realistic data streams representing high-mass star forming regions in our Galaxy. The synthetic output consists in images and photometric point source catalogues, in the IRAS and Herschel wavebands. In an era when large observational surveys are increasingly important, this tool can produce simulated infrared point-source catalogues of high-mass star forming regions on a Galactic scale. The approach used is to construct a synthetic Galaxy of star-forming regions represented by SED templates. The star-forming regions are distributed randomly along a four spiral arm morphology, although a wide range of geometries can be used including rings and different numbers of spiral arms. The caravela code then observes the synthetic Galaxy to produce simulated images and point source catalogues with appropriate sensitivity and angular resolution. caravela was first used to model the simulated Galaxy by constraining the synthetic output to observations made by IRAS. This numerical tool will allow the user to infer physical properties of the Galactic population of high-mass star forming regions from such observations. Second, the selected model was again observed with caravela in Herschel mode. These are therefore predictive results for the future Herschel observations. A model with 4.0×104 compact proto-stars embedded in larger grey-body envelopes (with T = 40 K and linear size scale lIII = 5.0 × 106 AU) is the best-fit model to the IRAS observational data set studied. We found a level of contamination from low- and intermediate-mass objects of " 90%. The modelled data set resulting from the Herschel simulation resulted in the detection of approximately twice as many Herschel objects than IRAS, which is consistent, in a limited way, with the real observed companion clump fraction (CCF) of 0.90 ± 0.07 (Thompson et al., 2006) means that on average there were observed 2 sources per one IRAS source. Our caravela and the real observed CCF are therefore consistent. caravela was coupled with an independent diffuse emission model (Paladini et al., 2007) and the resulting analysis is presented as an interesting seed for the future.