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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Photometric Standards for the Southern Hemisphere

Bok, B. J., Bok, P. F. 08 1900 (has links)
No description available.
82

Flattening of the Galactic Spheroid

White, S. D. M. 10 1900 (has links)
No description available.
83

Stezky v oblasti Pootaví / Ancient Trails in the area of the Otava river

Pitín, Michal January 2012 (has links)
TITLE: Ancient trails in the area of the Otava River AUTHOR: Michal Pitín DEPARTMENT: History and History Didactics Department SUPERVISOR: prof. PhDr. Petr Charvát, DrSc. ABSTRACT: The diploma thesis focuses on one of the modern science called stibology which concentrates on the human past and human's relation to the landscape and its settlement and mainly passing trails through the landscape. The aim of this work is to study settlement and possible passing of the communications through the landscape in the area of the Otava River since the Celtic settlement, but mainly at the Early and the High Middle Ages. The work focuses on realisation of the stibologic knowledge in the area of the town Strakonice at the period of the Early Middle Ages. It also shows that the theme of the old trails is missed out of education and its possible usage in the subject called The Heritage Education in School Education Programmes. The work also includes analysis of the cartographic materials and their information about trails passing the landscape. The work is completed by the picture supplement from the area of the Otava River and cartographic materials. KEYWORDS: trail, way, settlement, area of the Otava River
84

Performance analyses for large-scale antennas equipped two-way AF relaying and heterogeneous networks

Dai, Yongyu 14 September 2016 (has links)
In this dissertation, performance analyses for large-scale antennas equipped two-way amplify-and-forward (AF) relaying and heterogeneous network (HetNet) are carried out. Energy-efficiency oriented design becomes more important for the next generation of wireless systems, which motivates us to study the strong candidates, such as massive multiple-input multiple-output (MIMO) combined with cooperative relaying and HetNet. Based on the achievable rate analyses for both massive MIMO two-way AF relaying, effective power allocation schemes are presented to further improve system performance. Focusing on the MIMO downlinks in the HetNet, mean square error (MSE) based precoding schemes are designed and employed by the macro base station (BS) and the small cell (SC) nodes. Considering a HetNet where both macro BS and SC nodes are equipped with large-scale antenna arrays, the capacity lower bounds are derived, followed by the proposed user scheduling algorithms. The work on multi-pair two-way AF relaying with linear processing considers a system where multiple sources exchange information via a relay equipped with massive antennas. Given that channel estimation is non-ideal, and that the relay employs either maximum-ratio combining/maximum-ratio transmission (MRC/MRT) or zero-forcing reception/zero-forcing transmission (ZFR/ZFT) beamforming, we derive two corresponding closed-form lower bound expressions for the ergodic achievable rate of each pair sources. The closed-form expressions enable us to design an optimal power allocation (OPA) scheme that maximizes the sum spectral efficiency under certain practical constraints. As the antenna array size tends to infinity and the signal to noise ratios become very large, asymptotically optimal power allocation schemes in simple closed-form are derived. The capacity lower bounds are verified to be accurate predictors of the system performance by simulations, and the proposed OPA outperforms equal power allocation (EPA). It is also found that in the asymptotic regime, when MRC/MRT is used at the relay and the link end-to-end large-scale fading factors among all pairs are equal, the optimal power allocated to a user is inverse to the large-scale fading factor of the channel from the user to the relay, while OPA approaches EPA when ZFR/ZFT is adopted. The work on the MSE-based precoding design for MIMO downlinks investigates a HetNet system consisting of a macro tier overlaid with a second tier of SCs. First, a new sum-MSE of all users based minimization problem is proposed aiming to design a set of macro cell (MC) and SC transmit precoding matrices or vectors. To solve it, two different algorithms are presented. One is via a relaxed-constraints based alternating optimization (RAO) realized by efficient alternating optimization and relaxing non-convex constraints to convex ones. The other is via an unconstrained alternating optimization with normalization (UAON) implemented by introducing the constraints into the iterations with the normalization operation. Second, a separate MSE minimization based two-level precoder is proposed by considering the signal and interference terms corresponding to the macro tier and the individual SCs separately. Furthermore, robust precoders are designed correspondingly with estimated imperfect channel. Simulation results show that the sum-MSE based RAO algorithm provides the best MSE performance among the proposed schemes under a number of system configurations. When the number of antennas at the macro-BS is sufficiently large relative to the number of MUEs, the MSE of the separate MSE-based precoding is found to approach those of RAO and UAON. Together, this thesis provides a suite of three new precoding techniques that is expected to meet the need in a broad range of HetNet environments with balance between performance and complexity. The work on a large-scale HetNet studies the performance for MIMO downlink systems where both macro BS and SC nodes are equipped with large-scale antenna arrays. Suppose that the large-scale antenna arrays at both macro BS and SC nodes employ MRT or ZFT precoding, and transmit data streams to the served users simultaneously. A new pilot reuse pattern among small cells is proposed for channel estimation. Taking into account imperfect CSI, lower capacity bounds for MRT and ZFT are derived, respectively, in closed-form expressions involving only statistical CSI. Then asymptotic analyses for massive arrays are presented, from which we obtain the optimal antenna number ratio between BS and SCs under specific power scaling laws. Subsequently, two user scheduling algorithms, that is, greedy scheduling algorithm and asymptotical scheduling algorithm (ASA), are proposed based on the derived capacity lower bounds and asymptotic analyses, respectively. ASA is demonstrated to be a near optimal user scheduling scheme in the asymptotic regime and has low complexity. Finally, the derived closed-form achievable rate expressions are verified to be accurate predictors of the system performance by Monte-Carlo simulations. Numerical results demonstrate the effectiveness of the asymptotic analysis and the proposed user scheduling schemes. / Graduate / 0544 / 0984
85

Erfarenhetsåterföring : En framtagen metod för att främja samverkan / Experience feedback : A Proven Method to Promote Collaboration

Viklund, Simon, Grujovic, Nikola January 2017 (has links)
Sverige har sett en stor ökning av nyproducerade bostäder de senaste åren och byggbranschen har haft stor framgång. Med den kraftiga ökningen ställs nya krav på byggbolagen. Byggprocessen förkortas och effektiviseras med metoder som industriellt byggande. Men med en kortare byggtid och ökad effektivitet kan även problem i produktionen uppstå.   Syftet med denna rapport är att lokalisera återkommande problem och störningar som idag finns vid arbetsmoment i produktionen. Via workshoppar har vi samlat information från entreprenadbolagets egna hantverkare för att uppnå en klar bild av hur man går tillväga i byggprocessens utförandedelar samt kartlägga problem som uppkommer i produktionen.   Entreprenadbolaget är kvalitets-, miljö- och arbetsmiljöcertifierat gentemot kraven i ISO 9001, ISO 1400 och OHSAS 1800. Dessa certifieringar ställer krav på ett strukturerat förbättringsarbete. Direktiv för förbättringsarbeten inom bolaget existerar men det är något som inte når hela vägen. Det saknas ett medel i förbättringsarbetet som verkar för samtliga yrkesroller inom bolaget.  Med insamlad information som bakgrund har vi utvecklat ett medel som kan effektivisera delar i produktionen som samtidigt bidrar till en stimulerande arbetsmiljö för hantverkarna.  Området som valdes att studera vidare var hantverkarnas förslag om en pärm för speciallösningar vid bristfälliga konstruktioner och störningar i produktionen.  Det framtagna hjälpmedlet samt den utförda metoden i arbetet med att motverka återkommande problem och störningar i produktionen ser vi som ett steg i arbetet med att uppfylla ett av entreprenadbolagets årliga delmål, som innebär att främja samverkan mellan medarbetarna. / The construction industry in Sweden has seen a rise in recent years. With the increase of house production, new demands are being made on the construction companies. The construction process is shortened and made more efficient with methods such as using precast elements. But with shorter production times and increased effectivity, problems can arise.  The purpose of this report is to localize reoccurring problems in the production process. We have gathered information from the company’s own carpenters through workshops to get a clear picture of the problems in today’s production.  The construction company is quality, environment and work environment certified according to the requirements of ISO 9001, ISO 1400 and OHSAS 1800. These certifications require structured improvement work. A directive for improvement work within the company exists but is not ensued sufficiently. There are no means in the improvement work that works for all roles within the company. With the gathered information we’ve developed an instrument that can increase effectivity in the production process as well as contribute to a stimulating work environment for the carpenters.  The field we chose to study was the carpenter’s suggestion about a binder for special solutions at inadequate constructions and difficult situations. The developed instruments as well as the method used in our report to counteract reoccurring problems and disturbances in the production, contribute to the work in reaching the company’s goal to promote cooperation within the organization.
86

MULTI-WAY COMMUNICATION SYSTEM

Chinnam, S. 01 March 2017 (has links)
Videoconferencing is increasingly becoming a trend worldwide in applications where clients need to access lectures, meeting proceedings, communicating with family and friends etc. It provides a platform enabling the visual, audio and video communication between clients. The aim of this project is to utilize the open source Java software to build a desktop application enabling communication between clients. When a user needs to transfer a secured file, it’s unsafe to send it using social networking sites because of lack of security. So, with the “Multi-Way Communication System” (MWCS) we resolve some security issues. The MWCS is a highly secure way for file transfer, text and video conferencing.
87

Rights of public access for outdoor recreation in New Zealand

Booth, Kay Lenore, n/a January 2006 (has links)
This thesis explores the nature of public access rights for outdoor recreation in New Zealand. It aims to improve understanding of these rights by examining the New Zealand public policy framework for public access, the social constructions of access rights and the interaction of these dimensions via analysis of two contemporary New Zealand access issues: the foreshore access debate and the state-sponsored Land Access Review. An institutional arrangements framework forms the study�s conceptual basis and is critiqued for its value in the examination of rights of public access. Multiple qualitative methods were employed to collect data, including interviews with access actors, submission analysis, examination of public policy documents and critical interpretation of the access discourse within the mass media. Key themes from the international access literature are identified and the disparate nature of much of this research is highlighted. Within New Zealand, public access represents an area of research neglect. This thesis provides the first comprehensive study of rights of public access for outdoor recreation in New Zealand. A threshold has been reached in the evolution of access rights in New Zealand. Societal changes are perceived to be reducing the public�s traditional rights to access land for outdoor recreation. Owing to the importance of these rights within conceptions of New Zealand national identity, the Government is codifying access rights in a bid to protect them. Thus a shift in access arrangements is occurring, from reliance upon social customs to increasing use of public policy instruments. Access rights are being renegotiated within a highly contested environment. The debate is being staged within the political arena and via the national news media; access has become a significant national issue. As a result, the level of engagement has shifted from localised access transactions between landholders and recreationists, to a national discussion regarding competing rights to land. Access actors have reacted in different ways to the reforms of access arrangements, driven by the manner in which the proposals affect their property rights, social values and norms. Some reactions have been strident and confrontational. Inadequate public policy arrangements for access have created the 'space' for these multiple social constructions of access to develop. Convergence of a disparate and poorly enforced access public policy framework with varying social representations of access rights is influencing the access outcomes. The 'place' of public access within New Zealand society occurs at the intersection of several strongly-held cultural traditions, including private property rights, Maori customary rights, and a belief that it is a birthright to freely access the outdoors. The tension between these values underpins New Zealand�s unique (and changing) manifestation of the rights of the public to access land for recreation.
88

Titel: PMC WAY – Vägen till effektiv produktion : En studie om hur Lean production kan implementeras i ett mindre industriföretag

Callander, Sara, Hägerström, Malin January 2008 (has links)
<p>Titel: PMC WAY – Vägen till effektiv produktion</p><p>Problem: Hur kan PMC AB använda sig av Lean production-konceptet för att få en mer produktiv och effektiv produktion?</p><p>Syfte: Syftet med denna uppsats är att på uppdrag av PMC AB genomföra en studie om konceptet Lean production, för att sedan ta reda på hur PMC AB kan använda sig av detta koncept i sin produktion för att bli mer effektiva och produktiva.</p><p>Metod: För att genomföra studien har primär- och sekundär data använts. Den primära datan har samlats in genom intervjuer med personer på PMC AB samt observationer i produktionen. Den sekundära datan består av information insamlad från litteratur, artiklar, Internet och broschyrer.</p><p>Resultat: Studien visar att Lean production inte bara är användbart i stora österländska företag såsom Toyota, utan går att implementera på alla olika sorters företag. Konceptet betonar dock vikten av att grundligt gå igenom alla delar av företaget och inte glömma någon. Toyota Ways fyra huvudområden tar upp just alla företagets delar, vilket har gjort att modellen blivit så framgångsrik. De fyra huvuddelarna är filosofin, processerna, medarbetare och partners samt problemlösning. Alla fyra huvudområden är viktiga på olika sätt, men utan den långsiktiga filosofin blir det svårare, om inte omöjligt, att uppnå framgång med konceptet. Den långsiktiga filosofin sitter tätt ihop med att företaget måste få med sig alla medarbetare i detta långsiktiga tänkande. Ledarna måste få medarbetarna motiverade och känna ett engagemang gentemot verksamheten och inte bara ser det som ett arbete. Kan ledarna få medarbetarna motiverade går det lätt att förbättra processerna och få bort allt slöseri i företaget. Detta kan dock endast göras om medarbetarna och ledarna själva blir problemlösare och lär sig se och lösa problem. Därför måste företaget få dem att inse att problem är något bra och något som endast kan göra företaget bättre. Genom att använda sig av denna modell har vi kunnat få fram vad som är viktigt för PMC att tänka på för att får en mer produktiv och effektiv produktion. Vi har analyserat fram hur PMC kan förbättras, och lämnat förslag till ledningen som nu får ta över arbetet med att genomföra dessa förbättringar.</p>
89

Titel: PMC WAY – Vägen till effektiv produktion : En studie om hur Lean production kan implementeras i ett mindre industriföretag

Callander, Sara, Hägerström, Malin January 2008 (has links)
Titel: PMC WAY – Vägen till effektiv produktion Problem: Hur kan PMC AB använda sig av Lean production-konceptet för att få en mer produktiv och effektiv produktion? Syfte: Syftet med denna uppsats är att på uppdrag av PMC AB genomföra en studie om konceptet Lean production, för att sedan ta reda på hur PMC AB kan använda sig av detta koncept i sin produktion för att bli mer effektiva och produktiva. Metod: För att genomföra studien har primär- och sekundär data använts. Den primära datan har samlats in genom intervjuer med personer på PMC AB samt observationer i produktionen. Den sekundära datan består av information insamlad från litteratur, artiklar, Internet och broschyrer. Resultat: Studien visar att Lean production inte bara är användbart i stora österländska företag såsom Toyota, utan går att implementera på alla olika sorters företag. Konceptet betonar dock vikten av att grundligt gå igenom alla delar av företaget och inte glömma någon. Toyota Ways fyra huvudområden tar upp just alla företagets delar, vilket har gjort att modellen blivit så framgångsrik. De fyra huvuddelarna är filosofin, processerna, medarbetare och partners samt problemlösning. Alla fyra huvudområden är viktiga på olika sätt, men utan den långsiktiga filosofin blir det svårare, om inte omöjligt, att uppnå framgång med konceptet. Den långsiktiga filosofin sitter tätt ihop med att företaget måste få med sig alla medarbetare i detta långsiktiga tänkande. Ledarna måste få medarbetarna motiverade och känna ett engagemang gentemot verksamheten och inte bara ser det som ett arbete. Kan ledarna få medarbetarna motiverade går det lätt att förbättra processerna och få bort allt slöseri i företaget. Detta kan dock endast göras om medarbetarna och ledarna själva blir problemlösare och lär sig se och lösa problem. Därför måste företaget få dem att inse att problem är något bra och något som endast kan göra företaget bättre. Genom att använda sig av denna modell har vi kunnat få fram vad som är viktigt för PMC att tänka på för att får en mer produktiv och effektiv produktion. Vi har analyserat fram hur PMC kan förbättras, och lämnat förslag till ledningen som nu får ta över arbetet med att genomföra dessa förbättringar.
90

Gaussian Two-Way Channel with Constellation-based Input

Banijamali, Seyedershad January 2013 (has links)
Achieving a higher transmission rate had always been a goal in the field of communications. Having a two-way channel in which two nodes transmit and receive data at the same time, is an important tool to achieve this goal. A two-way channel is the first step from point-to-point communication channel toward multi-user networks. In its ideal form, we can transmit data two times faster by using a perfect two-way channel. However, the area of two-way channels had not been of interest of researchers during the past years and number of articles on this area is considerably low comparing to other types of multi-user communication networks, such as multiple-access channel, broadcast channel and interference channel. On the other hand, use of analog-to-digital converters (ADC) is a must in modern systems to enable us to analyze data faster; nevertheless, presence of ADC add some other difficulties to the system. In this thesis, different scenarios about two-way channel are studied. The Shannon's model of two-way channel and his inner and outer bounds on the capacity of this channel are presented. For the Gaussian Two-Way Channel with quantized output, in which the ambient noise has a Gaussian distribution, the expression of Shannon's inner bound for both Gaussian and discrete inputs are derived. The best uniform quantizer to obtain the maximum achievable rate for Gaussian input is found numerically. Then we will evaluate the additive noise model for the quantizer from an information theoretic point of view. For the discrete input, the method of rotating one input with respect to other one is employed to enlarge the achievable rate region. At last, two scenarios will be studied in which, minimizing the power of interference, does not necessarily maximizes the transmission rate.

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