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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

STUDIES ON ELECTRON-TRANSFER AS CATALYZED BY C-TYPE CYTOCHROMES

Miller, Warren Gregory, 1947- January 1973 (has links)
No description available.
82

Across-shelf sediment transport modeling and its application to storms at Duck, North Carolina /

Lee, Guan-hong. January 2000 (has links) (PDF)
Thesis (Ph. D.)--College of William and Mary. / Typescript (photocopy). Vita. Includes bibliographical references (leaves 130-137).
83

Développement économique et coordination des transports en Iran

Saghri, Farhad, January 1988 (has links)
Th. 3e cycle--Géogr.--Aix-Marseille 2, 1987.
84

Studie tvorby logistické koncepce ve vybraném podniku / Study of Creating a Logistics Concept in a Selected Company

Bobotová, Michaela January 2021 (has links)
The diploma thesis discusses the study of creation of new logistics conception and its proposal for the company, Schaeffler Skalica, spol. s r. o., which is engaged in the production of bearings and components for the automotive industry. The proposal of the new logistics conception relates to the stocks of Schaeffler Skalica, spol. s r. o., which are stored in the consignment warehouse in Germany and are supplied by Chinese supplier.
85

A Novel Dataset for the Transport Sector in a Province of Peru

Guerrero, Miguel Arango, Juárez, Pedro Shiguihara 01 January 2021 (has links)
El texto completo de este trabajo no está disponible en el Repositorio Académico UPC por restricciones de la casa editorial donde ha sido publicado. / Problems related to public transport and private transport in Peru are persistent. New proposals to solve them arise, currently the world of data analysis is starting in Peru, there are not many open datasets useful that allow proposing solutions in each environment. In this paper, we will collect relevant data of the transport located in a province of Peru with more than 1000 users involved, restricted by a delimited geographic area and with 2 years of operations and more than 3000 transport services tracked. In this way, we highlight the importance of the data, the possible potential uses within the transport, and a case of use of the collected dataset. / Revisión por pares
86

Turbulence and transport in stars and planets

Jermyn, Adam Sean January 2018 (has links)
In this dissertation I have argued that the study of stars and gaseous planets has relied too heavily on simplifying assumptions. In particular, I have demonstrated that the assumptions of spherical symmetry, thermal equilibrium, dynamical equilibrium and turbulent anisotropy all hide interesting phenomena which make a true difference to the structure and evolution of these bodies. To begin I developed new theoretical tools for probing these phenomena, starting with a new model of turbulent motion which accounts for many different sources of anisotropy. Building on this I studied rotating convection zones and determined scaling relations for the magnitude of differential rotation. In slowly-rotating systems the differential rotation is characterised by a power law with exponent of order unity, while in rapidly-rotating systems this exponent is strongly suppressed by the rotation. This provides a full characterisation of the magnitude of differential rotation in gaseous convection zones, and is in reasonable agreement with a wide array of simulations and observations. I then focused on the convection zones of rotating massive stars and found them to exhibit significantly anisotropic heat fluxes. This results in significant deviations from spherical symmetry and ultimately in qualitatively enhanced circulation currents in their envelopes. Accordingly, these stars ought to live much longer and have a different surface temperature. This potentially resolves several outstanding questions such as the anomalously slow evolution of stars on the giant branch, the dispersion in the observed properties of giant stars and the difficulty stellar modelling has to form massive binary black holes. In the same vein I examined the convection zones of bloated hot Jupiters and discovered a novel feedback mechanism between non-equilibrium tidal dissipation and the thermal structure of their upper envelopes. This mechanism stabilises shallow radiative zones against the convective instability, which would otherwise take over early on in the planet's formation as it proceeds to thermal equilibrium. Hence tidal dissipation is dramatically enhanced, which serves to inject significant quantities of heat into the upper layers of the planet and causes it to inflate. This mechanism can explain most of the observed population of inflated planets. Finally, I studied material mixing in the outer layers of accreting stars and developed a method for relating the observed surface chemistry to the bulk and accreting chemistries. This enables the direct inference of properties of circumstellar material and accretion rates for a wide variety of systems.
87

Logistikos veiksnių įtakos transporto srautų pasiskirstymui tyrimas / The research of the influence of logistical factors on transport flows distribution

Jaržemskis, Andrius 16 December 2004 (has links)
Pasaulio ekonomikos augimas, spartėjantis globalizacijos procesas, technologijų pažanga didina atstumus tarp žaliavų gavimo, gamybos ir pagamintų prekių naudojimo taškų. Gausėjant prekybinių ryšių bei plečiantis jų geografijai, didėja reikalavimai transporto ir logistikos paslaugas teikiančiam sektoriui. Regionų ekonominis augimas priklauso nuo to, kaip transporto sistema geba patenkinti žaliavų tiekėjų, gamintojų, prekybininkų ir vartotojų logistikos poreikius laiko, greičio, saugumo, sąnaudų prasmėmis. Transporto srautai ilgainiui prisitaiko prie kintamų regiono logistikos poreikių, tačiau dėl transporto sistemos inertiškumo tam sugaištama laiko. Lietuvoje reikšminga dalis bendrojo nacionalinio produkto sukuriama transporto ir logistikos sektoriuje, kadangi šalis yra stambių tranzitinių krovinių srautų kryžkelėje. Lietuvai tapus Europos Sąjungos nare, atsiveria tarptautinės prekybos augimo galimybes, Lietuva tampa Europos Sąjungos buferine zona prekybai su Rytų bloko šalimis, taigi teisinga Lietuvos transporto sistemos plėtros strategija gali suteikti Lietuvai didžiulį ekonominį potencialą, bendrojo vidaus produkto ir darbo vietų skaičiaus augimo perspektyvas. Transporto srautams užtikrinti būtina transporto infrastruktūra, kurios plėtrai yra labai svarbu nustatyti potencialius krovinių srautus. Transporto infrastruktūra labai imli kapitalui, todėl jos plėtros kryptys turi tiksliai atitikti logistikos poreikius, priešingu atveju milžiniškos investicijos nepateisinamos... [to full text] / Relevance of the dissertation is determined by the object of research – the influence of logistical factors on transport flows distribution. The growth of world economics, business globalization, progress in technology skills extends the distances between geographical points of raw materials resources, manufacturers and consumers. Due to the membership in the European Union (EU) Lithuania has got new opportunities for international trade growth, and all the Eastern Baltic countries have become the buffer region for the EU trading with the countries of the Eastern Europe and Asia. A proper transport policy and infrastructure development would increase significantly the GNP in warehousing, transport and distribution sectors. Forecasting of potential transport flows according to logistical requirements of freight suppliers is most important for transport network optimization. Scientific problem. Contemporary transport engineering theory approaches the peculiarities of transport flows formation too narrowly, only as an analysis of internal factors determining freight flows. There is no analysis of external factors. Many researchers assume that transport flows are determined only by the existing transport network and its characteristics. Other researchers consider transport flows as a result of logistic elements only. The estimating of internal and external logistical factors provides a possibility to forecast the transport flows. Aim of the research is to create a model of... [to full text]
88

The research of the influence of logistical factors on transport flows distribution / Logistikos veiksnių įtakos transporto srautų pasiskirstymui tyrimas

Jaržemskis, Andrius 16 December 2004 (has links)
Relevance of the dissertation is determined by the object of research – the influence of logistical factors on transport flows distribution. The growth of world economics, business globalization, progress in technology skills extends the distances between geographical points of raw materials resources, manufacturers and consumers. Due to the membership in the European Union (EU) Lithuania has got new opportunities for international trade growth, and all the Eastern Baltic countries have become the buffer region for the EU trading with the countries of the Eastern Europe and Asia. A proper transport policy and infrastructure development would increase significantly the GNP in warehousing, transport and distribution sectors. Forecasting of potential transport flows according to logistical requirements of freight suppliers is most important for transport network optimization. Scientific problem. Contemporary transport engineering theory approaches the peculiarities of transport flows formation too narrowly, only as an analysis of internal factors determining freight flows. There is no analysis of external factors. Many researchers assume that transport flows are determined only by the existing transport network and its characteristics. Other researchers consider transport flows as a result of logistic elements only. The estimating of internal and external logistical factors provides a possibility to forecast the transport flows. Aim of the research is to create a model of... [to full text] / Pasaulio ekonomikos augimas, spartėjantis globalizacijos procesas, technologijų pažanga didina atstumus tarp žaliavų gavimo, gamybos ir pagamintų prekių vartojimo taškų. Lietuva tapusi Europos Sąjungos nare, tampa Europos Sąjungos buferine zona prekybiniams mainams su Rytų Europos ir Azijos šalimis. Lietuvos transporto sistemą būtina pritaikyti esamiems ir potencialiems tarptautiniams krovinių srautams aptarnauti. Transporto srautų formavimosi išorinių veiksnių nustatymas ir įvertinimas Lietuvos transporto strategijoje gali suteikti šaliai didžiulį ekonominį potencialą.
89

Phonon and Carrier Transport in Semiconductors from First Principles:

Protik, Nakib Haider January 2019 (has links)
Thesis advisor: David Broido / We present fundamental studies of phonon and electron transport in semiconductors. First principles density functional theory (DFT) is combined with exact numerical solutions of the Boltzmann transport equation (BTE) for phonons and electrons to calculate various transport coefficients. The approach is used to determine the lattice thermal conductivity of three hexagonal polytypes of silicon carbide. The calculated results show excellent agreement with recent experiments. Next, using the infinite orders T-matrix approach, we calculate the effect of various neutral and charged substitution defects on the thermal conductivity of boron arsenide. Finally, we present a general coupled electron-phonon BTEs scheme designed to capture the mutual drag of the two interacting systems. By combining first principles calculations of anharmonic phonon interactions with phenomenological models of electron-phonon interactions, we apply our implementation of the coupled BTEs to calculate the thermal conductivity, mobility, Seebeck and Peltier coefficients of n-doped gallium arsenide. The measured low temperature enhancement in the Seebeck coefficient is captured using the solution of the fully coupled electron-phonon BTEs, while the uncoupled electron BTE fails to do so. This work gives insights into the fundamental nature of charge and heat transport in semiconductors and advances predictive ab initio computational approaches. We discuss possible extensions of our work. / Thesis (PhD) — Boston College, 2019. / Submitted to: Boston College. Graduate School of Arts and Sciences. / Discipline: Physics.
90

Two-Dimensional Transport Modeling of Tokamak Plasmas / トカマクプラズマにおける二次元輸送モデリング

Seto, Haruki 24 March 2014 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第18275号 / 工博第3867号 / 新制||工||1593(附属図書館) / 31133 / 京都大学大学院工学研究科原子核工学専攻 / (主査)教授 福山 淳, 教授 功刀 資彰, 准教授 村上 定義 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM

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