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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.
1

Die Sacherschliessung an der ETH-Bibliothek Zürich

Pika, Jiri 30 June 2003 (has links) (PDF)
Abgerundet wurde die Thematik durch Berichte aus Bibliotheken, so der ETH-Bibliothek, Zürich. Jiri Pika berichtet von Nutzer-Anforderungen und den Versuchen der Bibliothekare, diese z.B. durch Einsatz von Klassifikation zu erfüllen.
2

Die Sacherschliessung an der ETH-Bibliothek Zürich

Pika, Jiri 30 June 2003 (has links)
Abgerundet wurde die Thematik durch Berichte aus Bibliotheken, so der ETH-Bibliothek, Zürich. Jiri Pika berichtet von Nutzer-Anforderungen und den Versuchen der Bibliothekare, diese z.B. durch Einsatz von Klassifikation zu erfüllen.
3

Neues aus dem UDC-Consortium, Den Haag und der ETH-Bibliothek, Zürich

Pika, Jiri 01 February 2011 (has links) (PDF)
UDC-Consortium und ETH-Bibliothek : Kurzbericht
4

Exploring the water-energy nexus in the Omo river basin : A first step toward the development of an integrated hydrological-OSeMOSYS energy model

Sundin, Caroline January 2017 (has links)
The issues of conflicts between water, energy and food (often referred to as WEFnexus) has become a problem in countries where the energy system is rapidly expanding; one of those countries is Ethiopia. Ethiopia has a large potential of hydropower, which is what most of the electricity production currently comes from. However, this has proven to cause problems on other practices around or close to the power plants. An example is the Omo River basin where the development of the Gibe hydropower cascading scheme, with currently the three power plants Gibe I, I and III operating, have brought up the discussion of the downstream impact. For instance, indigenous people living in the lower parts of Omo river, practice flood recession agriculture, meaning they are depending on the seasonal floods. Further, Omo river has its outflow into Lake Turkana, Kenya, and the lake is highly dependent on the flow regime of the Omo river. Studies on the Omo river have been many, an example is the ones using Topkapi-ETH, a physically based rain-fall runoff model, that models the hydrological aspects of the river and considers, among others, water abstraction for irrigation and diversions to reservoirs for hydropower. However, the hydropower modelled worked on the basis of an averaged power demand; not necessarily reflect the actual demand. Hence, OSeMOSYS, the long-term energy optimization tool, was proposed to complement this study by modelling the energy system in Ethiopia. This current thesis had the aim to do so with the attempt to explore the possibility of a coupling between the models Topkapi-ETH and OSeMOSYS. The aim was to feed OSeMOSYS with varying water availability from Topkapi-ETH; in return, OSeMOSYS would feed Topkapi-ETH with a more realistic required energy production demand. An OSeMOSYS model was set up for Ethiopia, with national data extracted from the study The Electricity Model Base for Africa (TEMBA), disaggregating the hydropower to be able to model each of the hydropower plants in the Gibe cascading scheme individually. To couple the two models, two approaches were developed: Storage module and Reservoir module. The Storage module used the storage feature within OSeMOSYS and used the varying volume in the reservoir from Topkapi-ETH and converted it into an energy potential, as input to OSeMOSYS. The Reservoir module, on the other hand, used the external inflow (sum of all flows except upstream release), obtained from Topkapi-ETH, to the reservoir. An experimental set-up was performed to test how the OSeMOSYS model, with the two modules, would react to the input and which inputs were the driving forces affecting the electricity production. The results showed that OSeMOSYS can respond to the varying water availability received from Topkapi-ETH with the electricity production from the Gibe cascading scheme showed results reflecting this. However, there was a mismatch in the hydrological response in which OSeMOSYS did not seem to fully reflect the volume in the reservoir. For certain cases, the volume would be zero, indicating it would not store any water but instead use all incoming water directly for energy production. Hence, with respect to the results presented in this study, one can conclude that OSeMOSYS is prone to respond to changes in water availability. However, due to the incompatibility in the hydrological perspective in regard to the volume, the coupling is not complete. Before such a complete coupling can be achieved one needs to understand why OSeMOSYS does not reflect the hydrological characteristics. If this can be solved, then a feedback of the required energy production in the Gibe hydropower plants ought to be sent back to Topkapi-ETH. / Konflikten mellan vatten, energi och mat (ofta benämnt WEF-nexus) har blivit ett problem i länder där energisystemet snabbt utvecklas; ett av dessa länder är Etiopien. Etiopien har stor potential i vattenkraft, från vilket den största delen av elektriciteten kommer ifrån idag. Däremot har detta visat skapa problem kring andra verksamheter runtomkring eller i närheten av kraftverken. Ett exempel är Omo RIVER BASIN, beläget i sydvästra Etiopien. Exploateringen av Gibe vattenkraftverk i en kaskad schema, idag med de tre kraftverket Gibe I, IO och III i bruk, har skapat diskussion kring påverkan nedströms. Till exempel så bot Urbefolkningen i den nedre delen av Omo floden, där de utövar så kallad flood recession jordbruk, vilket innebär att de är beroende av säsonger av översvämningar för att bevattna marken. Vidare, Omo floden har sitt utflöde in i Lake Turkana, Kenya, och skön är starkt beroende av flödesregimen i Omo floden. Studier kring Omo floden har varit manga, ett exempel är de som har använt sig av Topkapi-ETH, en fysikaliskt baserad nederbörd yt-avrinnings modell, som modellerat de hydrologiska aspekterna I floden och tar hänsyn till, bland annat, extrahering av vatten i bevattningssyfte och diversion till vattenkraftsdam. Dock modellerade vattenkraftverken med utgångspunkt från ett uppskattat energibehov; nödvändigtvis inte det faktiska behovet. Således föreslogs att OSeMOSYS, en LONGTERM energi optimerings modell, skulle komplimentera denna studie genom att modellera energisystemet i Etiopien. Den här uppsatsen hade som avsikt att testa de föregående med en ansats att undersöka möjligheten att sammankoppla de två modellerna Topkapi-ETH and OSeMOSYS. Målet var att förse OSeMOSYS med en varierad vatten tillgänglighet från Topkapi-ETH; i retur skulle OSeMOSYS förse Topkapi-ETH med ett mer realistiskt energiproduktions behov. En modell i OSeMOSYS skapades för Etiopien, med nationella data extraherad från studien The Electricity Model Base for Africa (TEMBA), där vattenkraftverk disaggregerades för att kunna modellera varje kraftverk I Gibe kaskad schema enskilt. För att sammankoppla de två modeller skapades två tillvägagångssätt: Lagrings modul och Reservoar modul. Magasin modulen använde en lagrings funktion i OSeMOSYS med en funktion av den varierande volym i en reservoar från Topkapi-ETH som omvandlades till en potentiell energi. Reservoar modulen däremot använde externt inflöde (summan av alla flöden förutom upströms utflöde), taget från Topkapi-ETH till reservoaren. Ett försök sattes upp för att testa hur OSeMOSYS modellen, med de två modulerna, skulle reagera till indata och vilken indata som är drivande och påverkar produktionen av elektricitet. Resultaten visade att OSeMOSYS kan besvara ett varierade vatten tillgänglighet kommen från Topkapi-ETH där produktionen av elektricitet från Gibe kaskad schema återspeglade detta. Däremot fanns en missanpassning i den hydrologiska responsen där OSeMOSYS inte fullt ut avspeglade volymen i reservoaren. I vissa fall var volymen noll, vilket tyder på att inget vatten kan lagras utan allt inkommande vatten går direkt till turbiner för produktion av energi. Således, med avseende på resultaten presenterade i den här studien, kan en dra slutsatsen att OSeMOSYS kan svara på variationer i vatten tillgängligheten. Däremot, på grund av missanpassning i hydrologiska perspektivet med avseende på volmen, så är inte sammankopplingen mellan modellerna fullständig. Före en sådan fullständig sammankoppling kan uppnås måste en förstår varför OSeMOSYS inte återspeglar denna hydrologiska karaktär. Om detta kan förstås, så kan en feedback av den fordrade energiproduktionen i Gibe vattenkraftverken återsändas tillbaka till Topkapi-ETH.
5

Feldhecken und deren Einfluss auf Hochwasser und Naturschutz unter Berücksichtigung von agrarökonomischen Belangen im Naturraum Erzgebirge / Hedge rows and their influence on flood prevention and nature conservation under consideration of agricultural conditions in the mountain ranges of the Erzgebirge

Bianchin, Sylvi 24 January 2012 (has links) (PDF)
Ziel der Arbeit war die Beurteilung der räumlichen Verteilung und Struktur von Feldhecken hinsichtlich ihrer Wirkung für Hochwasser- und Naturschutz, sowie die Analyse von agrarökonomischen Faktoren, welche die Anlage von Hecken fördern beziehungsweise behindern. Folgende Fragen standen bei den Untersuchungen im Mittelpunkt: Wie muss eine Hecke sowohl aus naturschutzfachlicher als auch hydrologischer Sicht aufgebaut sein, um eine optimale Wirkung zu erzielen, und wie müssen die Rahmenbedingungen für Landwirte aussehen, damit Heckenstrukturen nicht nur erhalten, sondern auch neu angelegt werden können? Um diese komplexen Fragen zu beantworten, wurden verschiedene methodische Ansätze zur Analyse ökologischer, hydrologischer und entscheidungsbildender Prozesse gewählt. Um die Ergebnisse der verschiedenen Skalenarten (ordinal / kardinal) zu vergleichen und dabei aus verschiedenen Optionen eine für alle Ziele optimale Vorzugsvariante zu ermitteln, wurde am Ende eine Nutzwertanalyse durchgeführt. / There were two main purposes of the study; the evaluation of the spatial distribution and structural patterns of hedgerows in regard to their impact on flood prevention and nature conservation, and the investigation of factors facilitating or constraining the establishment of hedgerows. On the basis of this assessment, knowledge based recommendations were developed for the facilitation of hedgerows in agricultural landscapes in mountainous areas such as the Erzgebirge. The following questions were the main focus of the investigation: how should a hedgerow be composed to obtain the optimal effect from the nature conservation as well as the flood prevention point of view, and how should the general requirements for farmers be constructed so that hedgerows are not only maintained but also newly established. To answer these complex questions different methodologies were applied for analysing ecological, hydrological and decision-forming processes. In order to compare the results and hedgerow alternatives to determine the optimal choice, a value-benefit analysis was performed.
6

Feldhecken und deren Einfluss auf Hochwasser und Naturschutz unter Berücksichtigung von agrarökonomischen Belangen im Naturraum Erzgebirge

Bianchin, Sylvi 24 January 2012 (has links)
Ziel der Arbeit war die Beurteilung der räumlichen Verteilung und Struktur von Feldhecken hinsichtlich ihrer Wirkung für Hochwasser- und Naturschutz, sowie die Analyse von agrarökonomischen Faktoren, welche die Anlage von Hecken fördern beziehungsweise behindern. Folgende Fragen standen bei den Untersuchungen im Mittelpunkt: Wie muss eine Hecke sowohl aus naturschutzfachlicher als auch hydrologischer Sicht aufgebaut sein, um eine optimale Wirkung zu erzielen, und wie müssen die Rahmenbedingungen für Landwirte aussehen, damit Heckenstrukturen nicht nur erhalten, sondern auch neu angelegt werden können? Um diese komplexen Fragen zu beantworten, wurden verschiedene methodische Ansätze zur Analyse ökologischer, hydrologischer und entscheidungsbildender Prozesse gewählt. Um die Ergebnisse der verschiedenen Skalenarten (ordinal / kardinal) zu vergleichen und dabei aus verschiedenen Optionen eine für alle Ziele optimale Vorzugsvariante zu ermitteln, wurde am Ende eine Nutzwertanalyse durchgeführt. / There were two main purposes of the study; the evaluation of the spatial distribution and structural patterns of hedgerows in regard to their impact on flood prevention and nature conservation, and the investigation of factors facilitating or constraining the establishment of hedgerows. On the basis of this assessment, knowledge based recommendations were developed for the facilitation of hedgerows in agricultural landscapes in mountainous areas such as the Erzgebirge. The following questions were the main focus of the investigation: how should a hedgerow be composed to obtain the optimal effect from the nature conservation as well as the flood prevention point of view, and how should the general requirements for farmers be constructed so that hedgerows are not only maintained but also newly established. To answer these complex questions different methodologies were applied for analysing ecological, hydrological and decision-forming processes. In order to compare the results and hedgerow alternatives to determine the optimal choice, a value-benefit analysis was performed.
7

Data Logging for Controller Area Network of Autonomous Vehicles : An Investigation of a CAN-Ethernet Gateway / Dataloggning av Controller Area Network för Autonoma Fordon : En undersökning av en nätsluss för CAN-Ethernet

Grönås, Daniel, Mazur, Fredrik January 2022 (has links)
With the development of autonomous vehicles, more and more technology is introduced into the automotive industry. Ethernet has found its way into the vehicle network, and it is forced to coexist with the well-established CAN bus. In terms of data acquisition, the presence of a mixed network brings challenges with significant changes in network architecture. This thesis explores CAN-Ethernet gateways as a replacement for the PCIe bus CAN transceivers utilized in today's logging systems, with the purpose to improve the adaptability of the autonomous logging system. A CAN-Ethernet gateway was implemented using Kvaser's DIN Rail SE400S-X10in an experimental comparison against the PCIe logging solution, including both classical CAN and CAN FD communication. In addition, a case study on the benefits and drawbacks with implementing an Ethernet architecture was performed, utilizing semi-structured interviews. It was concluded that a CAN-Ethernet gateway provides a robust solution in relation to data loss. Throughout the tests, the message loss rate was 0% for both logging solutions. However, CAN-Ethernetlogging introduced additional delay into the system. For the tests on a truck simulation rig the mean additional delay from a CAN-Ethernet gateway, compared to the existing PCIe-CAN logging, was 2 ms. Moreover, some spikes occurred and in a number of cases it could be up to 6 ms in additional delay compared to the existing PCIe logging. It was also proven difficult to time synchronize the gateway with the autonomous logging system, and unknown delays had an impact. Relevant metrics were obtained from relative measurements of side-by-side logging between the PCIe and CAN-Ethernet communication. The standard deviation and fluctuation of the delay were relevant metrics, since smaller fluctuations made the delay more predictable and real-time compatible. A CAN-Ethernet deployment may create a more complex architecture in general, and as of now has limitations for real-time systems. On the other hand, it may offer significant possibilities in future development of a more adaptable and scalable logging system. / Med utvecklingen av autonoma fordon har mer och mer teknologi introducerats inom fordonsindustrin. Ethernet har funnit sin väg in i fordonsnätverket och tvingas existera sida vid sida med den väletablerade CAN-bussen. För dataloggning orsakar närvaron av ett blandat nätverk (med både CAN och Ethernet) utmaningar i samband med stora förändringar inom nätverksarkitektur. Det här examensarbetet utforskar nätslussar för CAN-Ethernet som en ersättare till PCIe-bussens CAN-sändtagare som används i dagens loggningssystem. En CAN-Ethernet-nätsluss implementerades genom att använda Kvasers DIN Rail SE400S-X10 i en experimentell jämförelse med PCIe-loggningssystemet, och inkluderade både klassisk CAN samt CAN FD kommunikation. I tillägg gjordes en fallstudie om fördelar och nackdelar med att implementera en Ethernet-arkitektur,vilken grundades på semi-strukturerade intervjuer. Slutsatsen var att CAN-Ethernet-nätslussar tillhandahåller en robust lösning i förhållande till dataförlust. Under alla testerna var meddelandeförlusten 0% hos båda loggningsmetoderna. Däremot introducerade CAN-Ethernet-loggning en ökad fördröjning till systemet. För testerna på lastbilsriggsimulatorn var fördröjningen 2 ms jämfört med PCIe-CAN-loggningen. Dessutom förekom spikar i fördröjningen och i vissa fall resulterade fördröjningen i upp mot 6 ms, jämfört mot den befintliga PCIe-loggningen. Det visade sig även vara svårt att tidssynkronisera nätslussen med det autonoma loggningssystemet och okända fördröjningar hade en inverkan. Relevanta mått erhölls från relativa mätningar av jämsides loggning mellan PCIe och CAN-Ethernet kommunikation. Standardavvikelsen och fluktuation av fördröjningen var relevanta mått eftersom mindre fluktuationer resulterade i en mer förutsägbar samt realtidskompatibel fördröjning. Användningen av CAN-Ethernet kan, i allmänhet, resultera i en mer avancerad arkitektur och har i dagsläget begränsningar inom realtidssystem. Å andra sidan kan CAN-Ethernet erbjuda markanta möjligheter inom framtida utveckling av ett mer modulärt och skalbart loggningssystem.
8

Development of a tool to test computer protocols

Myburgh, W. D 04 1900 (has links)
Thesis (MSc) -- Stellenbosch University, 2003. / ENGLISH ABSTRACT: Software testing tools simplify and automate the menial work associated with testing. Moreover, for complex concurrent software such as computer protocols, testing tools allow testing on an abstract level that is independent of specific implementations. Standard conformance testing methodologies and a number of testing tools are commercially available, but detailed descriptions of the implementation of such testing tools are not widely available. This thesis investigates the development of a tool for automated protocol testing in the ETH Oberon development environment. The need to develop a protocol testing tool that automates the execution of specified test cases was identified in collaboration with a local company that develops protocols in the programming language Oberon. Oberon is a strongly typed secure language that supports modularisation and promotes a readable programming style. The required tool should translate specified test cases into executable test code supported by a runtime environment. A test case consists of a sequence of input actions to which the software under test is expected to respond by executing observable output actions. A number of issues are considered of which the first is concerned with the representation of test case specifications. For this, a notation was used that is basically a subset of the test specification language TTCN-3 as standardised by the European Telecommunications Standards Institute. The second issue is the format of executable test cases and a suitable runtime environment. A translator was developed that generates executable Oberon code from specified test cases. The compiled test code is supported by a runtime library, which is part of the tool. Due to the concurrent nature of a protocol environment, concurrent processes in the runtime environment are identified. Since ETH Oberon supports multitasking in a limited sense, test cases are executed as cooperating background tasks. The third issue is concerned with the interaction between an executing test case and a system under test. It is addressed by an implementation dependent interface that maps specified test interactions onto real interactions as required by the test context in which an implementation under test operates. A supporting protocol to access the service boundary of an implementation under test remotely and underlying protocol service providers are part of a test context. The ETH Oberon system provides a platform that simplifies the implementation of protocol test systems, due to its size and simple task mechanism. Operating system functionality considered as essential is pointed out in general terms since other systems could be used to support such testing tools. In conclusion, directions for future work are proposed. / AFRIKAANSE OPSOMMING: Toetsstelsels vir programmatuur vereenvoudig en outomatiseer die slaafse werk wat met toetsing assosieer word. 'n Toetsstelsel laat verder toe dat komplekse gelyklopende programmatuur, soos rekenaarprotokolle, op 'n abstrakte vlak getoets word, wat onafhanklik van spesifieke implementasies is. Daar bestaan standaard metodes vir konformeringstoetsing en 'n aantal toetsstelsels is kommersiëel beskikbaar. Uitvoerige beskrywings van die implementering van sulke stelsels is egter nie algemeen beskikbaar nie. Hierdie tesis ondersoek die ontwikkeling van 'n stelsel vir outomatiese toetsing van protokolle in die ontwikkelingsomgewing van ETH Oberon. Die behoefte om 'n protokoltoetsstelsel te ontwikkel, wat die uitvoering van gespesifiseerde toetsgevalle outomatiseer, is geïdentifiseer in oorleg met 'n plaaslike maatskappy wat protokolle ontwikkel in die Oberon programmeertaal. Oberon is 'n sterkgetipeerde taal wat modularisering ondersteun en a leesbare programmeerstyl bevorder. Die toestsstelsel moet gespesifiseerde toetsgevalle vertaal na uitvoerbare toetskode wat ondersteun word deur 'n looptydomgewing. 'n Toetsgeval bestaan uit 'n reeks van toevoeraksies waarop verwag word dat die programmatuur wat getoets word, sal reageer deur die uitvoering van afvoeraksies wat waargeneem kan word. 'n Aantal kwessies word aangeraak, waarvan die eerste te make het met die voorstelling van die spesifikasie van toetsgevalle. Hiervoor is 'n notasie gebruik wat in wese 'n subversameling van die toetsspesifikasietaal TTCN-3 is. TTCN-3 is gestandardiseer deur die European Telecommunications Standards Institute. Die tweede kwessie is die formaat van uitvoerbare toetsgevalle en 'n geskikte looptydomgewing. 'n Vertaler is ontwikkel wat uitvoerbare Oberon-kode genereer vanaf gespesifiseerde toetsgevalle. Die vertaalde toetskode word ondersteun deur 'n biblioteek van looptydfunksies, wat deel van die stelsel is. As gevolg van die eienskap dat 'n protokolomgewing uit gelyklopende prosesse bestaan, word daar verskillende tipes van gelyklopende prosesse in 'n protokoltoetsstelsel geïdentifiseer. Aangesien ETH Oberon 'n beperkte multitaakstelsel is, word toetsgevalle vertaal na eindige outomate wat uitgevoer word as samewerkende agtergrondtake. Die derde kwessie het te make met die interaksie tussen 'n toetsgeval wat uitgevoer word en die stelsel wat getoets word. Dit word aangespreek deur 'n koppelvlak wat gespesifiseerde interaksies afbeeld op werklike interaksies soos vereis deur die konteks waarin 'n implementasie onderworpe aan toetsing uitvoer. 'n Ondersteunende protokolom die dienskoppelvlak van die implementasie oor 'n afstand te bereik en ander onderliggende protokoldienste is deel van 'n toetskonteks. Die ETH Oberon-stelsel help in die vereenvoudiging van die implementasie van protokol toetsstelsels, as gevolg van die stelsel se grootte en die eenvoudige taakhanteerder . Die essensiële funksionaliteit van bedryfsstelsels word uitgelig in algemene terme omdat ander stelsels gebruik kan word om toetsstelsels te ondersteun. Ten slotte word voorstelle vir opvolgwerk gemaak.
9

Neues aus dem UDC-Consortium, Den Haag und der ETH-Bibliothek, Zürich

Pika, Jiri 01 February 2011 (has links)
UDC-Consortium und ETH-Bibliothek : Kurzbericht
10

Anpassung von WaSiM-ETH und die Erstellung und Berechnung von Landnutzungs- und Klimaszenarien für die Niederschlag-Abfluss-Modellierung am Beispiel des Osterzgebirges

Pöhler, Hannaleena Annikki 21 July 2009 (has links) (PDF)
Für das Verbundprojekt EMTAL (Einzugsgebietsmanagement von Talsperren in Mittelgebirgslandschaften) wurden Methoden zur Klärung hydrologischer Fragen entwickelt. Das dafür gewählte Modell WaSiM-ETH kann den Abfluss im Untersuchungsgebiet gut reproduzieren und ist unter Verwendung physikalisch basierter Teilmodule auf ähnliche Einzugsgebiete übertragbar. Es kann in einer hohen Bandbreite zeitlicher und räumlicher Diskretisierung verwendet werden. Bei der Modellierung verschiedener Landnutzungsszenarien zeigen sich Grenzen im Prozessverständnis, der Parametrisierung bekannter oder vermuteter Prozessse und in der Darstellung verschiedener Prozesse durch das Modell. Innerhalb streng festgelegter Randbedingungen können aber plausible Ergebnisse erlangt werden. Zusätzlich wurden meteorologische Zeitreihen für die Niederschlag-Abfluss-Modellierung bis 2050 erstellt. Die Effekte von Klimaänderungen auf den Abfluss werden gut abgebildet. Die Grenzen der Modellierung liegen hier in erster Linie bei der Güte der Eingangsdaten aus den Klimaprognosen.

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