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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.
151

On the Shape Parameter of the MFS-MPS Scheme

Lin, Guo-Hwa 23 August 2010 (has links)
In this paper, we use the newly developed method of particular solution (MPS) and one-stage method of fundamental solution (MFS-MPS) for solving partial differential equation (PDE). In the 1-D Poisson equation, we prove the solution of MFS-MPS is converge to Spectral Collocation Method using Polynomial, and show that the numerical solution similar to those of using the method of particular solution (MPS), Kansa's method, and Spectral Collocation Method using Polynomial (SCMP). In 2-D, we also test these results for the Poisson equation and find the error behaviors.
152

Vessel Segmentation Using Shallow Water Equations

Nar, Fatih 01 May 2011 (has links) (PDF)
This thesis investigates the feasibility of using fluid flow as a deformable model for segmenting vessels in 2D and 3D medical images. Exploiting fluid flow in vessel segmentation is biologically plausible since vessels naturally provide the medium for blood transportation. Fluid flow can be used as a basis for powerful vessel segmentation because streaming fluid regions can merge and split providing topological adaptivity. In addition, the fluid can also flow through small gaps formed by imaging artifacts building connections between disconnected areas. In our study, due to their simplicity, parallelism, and low computational cost compared to other fluid simulation methods, linearized shallow water equations (LSWE) are used. The method developed herein is validated using synthetic data sets, two clinical datasets, and publicly available simulated datasets which contain Magnetic Resonance Angiography (MRA) images, Magnetic Resonance Venography (MRV) images and retinal angiography images. Depending on image size, one to two order of magnitude speed ups are obtained with developed parallel implementation using Nvidia Compute Unified Device Architecture (CUDA) compared to single-core and multicore CPU implementation.
153

On the Increasingly Flat RBFs Based Solution Methods for Elliptic PDEs and Interpolations

Yen, Hong-da 20 July 2009 (has links)
Many types of radial basis functions, such as multiquadrics, contain a free parameter called shape factor, which controls the flatness of RBFs. In the 1-D problems, Fornberg et al. [2] proved that with simple conditions on the increasingly flat radial basis function, the solutions converge to the Lagrange interpolating. In this report, we study and extend it to the 1-D Poisson equation RBFs direct solver, and observed that the interpolants converge to the Spectral Collocation Method using Polynomial. In 2-D, however, Fornberg et al. [2] observed that limit of interpolants fails to exist in cases of highly regular grid layouts. We also test this in the PDEs solver and found the error behavior is different from interpolating problem.
154

Komunikacijos sistema neįgaliesiems / Communication system for disabled

Balbonas, Dainius 11 June 2004 (has links)
The developing stages of communication system for the physically disabled persons with speech and language impairments are presented in this master job. The system was developed in pursuance of international Eureka project E! 2707. The author tried to take notice of disables situation in society of 21’st century and tried to formulate the problems witch appearing then disables trying to use modern communication technologies (internet, e-mail, text typing). A review of compensation method for disables was done. Also the market of compensatory devices was reviewed. Only when analysis of users was done, compensatory methods for physically disabled person was review, and facilities was sum up, the model of communications system and the demo version of software for the physically disabled persons with speech and language impairments was created. The design software lets to type text, to use e-mail possibilities, to browse Internet. All these functions can be achieved using one or two ON-OFF buttons and virtual keyboard. The experiments shows that is possible to achieve text typing speed approximately 20 symbols per minute.
155

Žemės naudojimo reglamentavimas rengiant valstybinių parkų tvarkymo planus (Anykščių regioninio parko pavyzdžiu) / The regulation of land using by making the reguliative drafts of national parks. (By Anyksciai regional park)

Šerepka, Kęstutis 28 January 2008 (has links)
Magistriniame darbe nagrinėjamas žemės naudojimo reglamentavimas rengiant valstybinių parkų tvarkymo planus. Tvarkymo planų rengimo metodika valstybiniams parkams, biosferos rezervatams ir draustiniams yra patvirtinta Aplinkos ministro įsakymu, todėl žemės naudojimo reglamentavimas buvo nagrinėjamas Anykščių regioninio parko pavyzdžiu. Tvarkymo planai – specialiojo teritorijų planavimo dokumentai rengiami saugomų teritorijų apsaugą ir naudojimą reguliuojančioms kraštovaizdžio tvarkymo zonoms bei jų reglamentams nustatyti, apsaugos ir tvarkymo kryptims bei priemonėms, o taip pat ir kraštovaizdžio formavimo, rekreacinės infrastruktūros kūrimo, numatyti. Parko teritorijoje kraštovaizdžio tvarkymo zonos sudaro kraštotvarkinių kategorijų sistemą, skirstomą į konservacinės paskirties žemę (152,9 ha), miškų ūkio paskirties žemę ( 6020,2 ha), žemės ūkio paskirties žemę ( 6726,8 ha), gyvenamosios paskirties žemę ( 1056 ha), rekreacinės paskirties žemę ( 327,9 ha), vandens ūkio paskirties žemę ( 1144,4 ha). Tvarkymo plane išnagrinėta galima veikla kiekvienoje iš šių zonų, nubrėžtos jų apsaugos ir tvarkymo kryptys, numatytas tolesnis parko teritorijos vystymas. Pagrindinis tvarkymo plane keliamas uždavinys išsaugoti ir pritaikyti lankymui saugomą teritoriją, nes visa saugomų teritorijų sistema sukurta tam, kad ateities kartoms būtų išsaugotas dabar mūsų turimos gamtos ir kultūros paveldo vertybės. / There is analysed the regulation of land using by preparing the regulative drafts of National parks in the master work. The methodology of regulative drafts for national parks, biosphere reserves and conservation areas is sealed by the order of Environmental minister. Consequently, the regulation of land using was analysed by Anyksciai regional park example. The regulative drafts – there are the papers of special planning areas. They are prepared in case to evaluate landscape regulative areas and their regulations, trends and mediums of protection and regulation, and also to provide landscape formation and development of recreation facility. The landscape regulative areas compose region regulation category system in park territory. This system is devided into conservation land (152,9 ha), forestry land (6020,2 ha), agriculture land (6726,8 ha), locality land (1056 ha), recreation land (327,9 ha) and water economy land (1144,4 ha). There are analysed possible activity in each area, defined their protection and regulation trends, supposed further park area development in the regulation draft. The main task of regulation draft is to conserve and apply protected area for visiting. Because all protected areas system is created to save our nature and cultural heritage for muture generations.
156

Theoretical Framework for Modeling Ingressive Phonation

Brougham, Michael V Unknown Date
No description available.
157

Mažaenerginio administracinio pastato sezoninės energijos poreikių ypatybės / Seasonal Peculiarities of Energy Demands of a Low Energy Office Building

Subačiūtė, Ieva 20 July 2012 (has links)
Baigiamajame magistro darbe nagrinėjamas mažaenergis administracinis pastatas ir AEI panaudojimo jame galimybės Lietuvos meteorologinėmis sąlygomis. Naudojant modeliavimo priemonę TRNSYS sukuriami mažaenerginio administracinio pastato bei AEI sistemų skaičiavimo – valdymo modeliai: saulės kolektoriai, foto elementai, vėjo jėgainės, šilumos siurbliai, imantys šilumą iš grunto bei oro. Atlikus modeliavimą gauti pastato energijos suvartojimai šildymui (54 kWh/m2), vėsinimui (20 kWh/m2) bei elektros (48 kWh/m2). Metiniame pastato energijos balanse, energija pagaminta iš AEI gali padengti 56,6% reikalingos šiluminės energijos, 102,9 % energijos reikalingos vėsinimui ir 4,5 % reikalingo elektros kiekio. Pastato energijos poreikių jautrumo analizė atliekiama 3 pastato variantams. Pastebėta, kad esant didesniam stiklinių atitvarų plotui pietinėje pastato pusėje pagamintas šilumos kiekis iš AEI gali padengti net 85 % pastatui reikalingo šilumos kiekio. Tačiau beveik du kartus išaugo energijos poreikis pastato vėsinimui. Mažiausias vėsinimo kiekis reikalingas stačiakampio ploto pastatui. Apibendrinus rezultatus, pateiktos išvados ir rekomendacijos. Darbą sudaro 5 dalys: įvadas, 5 skyriai, išvados ir rekomendacijos, literatūros sąrašas. Darbo apimtis – 63 p. teksto be priedų, 31 iliustr., 16 lent., 27 bibliografiniai šaltiniai. Atskirai pridedami darbo priedai. / Thesis examined low energy office building and possibilities of renewable energy use in it by Lithuanian meteorology conditions. Using TRNSYS simulation tool the computing-control models for low energy office building and renewable energy systems (RES) (solar collectors, photovoltaic, wind turbines and heat pumps taking the heat from the soil and air) are created. After the simulation buildings’ energy consumption for heating (54kWh/m2), cooling (20 kWh/m2) and electricity (48 kWh/m2) were obtained. The annual building energy balance: an energy produced from RES can cover 56.6 % of the necessary thermal energy, 102.9 % of the energy required for cooling and 4.5 % required for electricity generation. The buildings’ energy demand sensitivity analysis is performed for three buildings’ variants. It is observed that of a larger area of the glass envelope of the building in southern direction the amount of heat produced from RES can cover up to 85% of the building required heat. However, almost twice rises electricity demand in cooling of the building. The minimum amount of cooling is required for a rectangular area building. Summarizing the results, conclusions and recommendations are presented. The work consists of 5 parts: introduction, 5 chapters, conclusions and recommendations, references. Work size – 63 pages without appendices, 31 figures, 16 tables, 27 references. Appendices.
158

Αναγνώριση συμβάντων ακουστικής εκπομπής και υλοποίηση σε μικρουπολογιστικό σύστημα ειδικού σκοπού

Κόγια, Μαρία 08 January 2013 (has links)
Η Ακουστική Εκπομπή είναι μία μέθοδος αναγνώρισης και εντοπισμού αστοχιών σε υλικά ή/και κατασκευές είτε κατά τη διάρκεια χρήσης ή λειτουργίας τους είτε με την άσκηση δύναμης σε αυτά. Με άλλα λόγια, με την τεχνική αυτή μπορούμε να προσδιορίσουμε το πότε και το πού μία αστοχία έχει πραγματοποιηθεί, όταν το αντικείμενο που εξετάζουμε είναι σε λειτουργία ή του ασκούμε κάποια πίεση. Στη διπλωματική αυτή εργασία, στόχος μας είναι η ανάπτυξη ειδικού λογισμικού για τον εντοπισμό αστοχιών σε υπό εξέταση αντικείμενα με τη χρήση ενός και μόνο αισθητήρα. Το εγχείρημα αυτό είναι ιδιαιτέρως ενδιαφέρον και τα αποτελέσματά του χρήσιμα, αφού σε αυτό προσπαθούμε να εντοπίσουμε πηγές αστοχιών χρησιμοποιώντας λιγότερο εξοπλισμό απ’ ότι συνηθίζεται, απλά με έναν αισθητήρα και ένα προγραμματιζόμενο ενσωματωμένο σύστημα. Έτσι, το κόστος κατασκευής είναι μικρό και εξοικονομείται χώρος για την εγκατάσταση του εξοπλισμού. / The Acoustic Emission is a method that we use in order to recognize and locate failures in materials or/and structures either while we are using them or they are operating or by exerting force upon them. In other words, implementing this technique, we are able to identify when and where a discontinuity has occurred while either the object, we examine, is working or we are pressing it. In this way, as we become aware of the exact place and extent of defects of useful objects at the time they happen, we are able to refit them readily. In this thesis, our goal is to configure a program for locating discontinuities in objects, which we examine, by the usage of a single sensor. This project is particularly interesting and the results that have been come out of it are useful as well, since we try to locate the sources of these failures by making use of less equipment than it is expected to; merely with a single sensor and one programmable embedded system. Therefore, the cost of the whole construction is little and we are in need of less space for the equipment to be established.
159

Uso do Solo do Município de Rio das Ostras como uso em processos de sorção como etapa de tratamento de lixiviados de aterros sanitários. / Land Use of the City of Rio das Ostras as use in sorption processes and treatment of leachate from landfills step.

Monica Bomilcar Albano 17 March 2008 (has links)
Este trabalho investiga a utilização do solo do Aterro Sanitário de Rio das Ostras como forma de tratamento de lixiviado, de modo a quantificar a redução de contaminastes, cor e valores de DQO. A utilização do solo argiloso para redução de contaminantes, cor e valores de valores de DQO foi estudada usando três lixiviados diferentes: Rio das Ostras, Morro do Céu e aterro grande porte em ensaios para medida de sorção. As análises de redução de cor e valores de DQO foram realizadas, tendo o resultado mostrado uma redução de cor que variou de 45 a 73% e valores de DQO entre 7 e 66%, usando ensaios do tipo Batch Tests pelo Método CSI. Outros ensaios foram realizados pelo Método ECI de Batch Tests que mostraram resultados melhores de redução de cor, entre 60 e 80% apresentando uma capacidade de sorção do solo argiloso de 22 mg/g. Os ensaios de sorção, com os três lixiviados, foram também utilizados, para estudo do comportamento de certos contaminantes amônio, potássio, sódio e cálcio com relação ao solo argiloso de Rio das Ostras. Foi observada uma dessorção para os íons sódio e cálcio e também uma alta sorção para os íons amônio e potássio. O solo e o lixiviado do Aterro Sanitário de Rio das Ostras foram utilizados para pesquisa de determinação dos coeficientes de difusão molecular para os íons amônio, potássio, sódio, cloreto e cálcio, simulados nos programas computacionais POLLUTE e MPHMTP. Os resultados do coeficiente de difusão para o POLLUTE variaram entre 0,03 m2/ano e 0,1 m2/ano sendo no MPHMTP de 0,06 m2/ano a 0,1 m2/ano. Os dados experimentais mostraram melhor comportamento nas simulações realizadas no MPHMTP. / This work is an investigation study of the use of Rio das Ostras MSW clay soil as a leachate treatment. The activity of the clay soil for color and COD reduction was studied using three different leachates: Rio das Ostras, Morro do Céu and another one without identification. Analysis of the color and COD reduction were performed and the results for color reduction vary from 45 to 73% and the COD reduction from 7 to 66 %, using CSI Batch Tests. Other tests using one of the leachates with ECI Batch Tests presented better results for color reduction, the results of ECI tests showed an sorption capacity for the clay soil of 22 mg/g. The sorption tests, with the three leachates, were also performed to study the behavior of certain contaminants; Sodium, Ammonium, Potassium and Calcium in the presence of a clay soil from Rio das Ostras MSW. A Sodium and Calcium desorption was observed as well as a higher sorption for ammonium and potassium. The molecular diffusion coefficients determination using the soil and the leachate of Rio das Ostras MSW for the Chloride, Sodium, Ammonium, Potassium and Calcium ions were researched and the software POLLUTE and MPHMPT (Multi Phase Heat and Mass transfer program) were used. The results vary between 0,03 m2/year to 0,1 m2/year for POLLUTE software and 0,06 m2/year to 0,1 m2/ year for MPHMPT model. The experimental data showed better agreement for MPHMPT.
160

Valence Band Properties of the Ruthenium Complex Catalyst Using Ab Initio Theory

Svensson, Pamela H.W. January 2018 (has links)
Ruthenium complexes has been geometrically optimized with different combinations of basis sets. Using single point calculation, the Density of States and partial Density of States has been calculated. RuIII-OH2 experienced a shift towards higher binding energies. The Ru atom plays a vast role in the contribution to the HOMO level of each complex, dominating in RuII-OH2. The nitrogen atom gives a small contribution for each complex in the HOMO region except for RuII-OH2 where it only appears at higher binding energies. The energy difference between RuII-OH2 and RuIII-OH/RuIV-O is about 1.1 eV whereas it experimentally is shown to be around 1.5 eV for the same complexes.

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