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The study of the reciprocating internal combustion engine is of prime importance to the student engineer. In our present civilization, the number of units and the total rated power of internal combustion engines in use is far greater than that of all other prime movers combined. Many basic engineering problems are present in the study of the operation of internal combustion engines. A number of mechanical and electrical devices have been developed to aid the engineer in his studies of engine performance. The purpose of this project is to provide the Mechanical Engineering Department of the North Dakota State University with an addition to its laboratory facilities which will enable the student to do additional experimental work in the internal combustion engines field. / North Dakota State University (NDSU)

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.

The static cone penetrometer is an in-situ testing tool which was originally developed to derive information on soil type and soil strength. More recently, it has found application in liquefaction assessment. Typical cone penetrometers are heavy duty devices which are operated with the assistance of a drill rig. However, this capacity is not necessary in the case of field studies of liquefaction, since liquefaction usually occurs at relatively shallow depths. This thesis is directed to the goal of the development of a miniature, lightweight cone penetrometer which can be used in earthquake reconnaissance studies related to liquefaction problems. The research for this thesis involved four principal objectives: 1. Development of procedures to automatically acquire and process measurements from a miniature electrical cone; 2. Develop and perform tests in a model soil-filled bin to calibrate the cone; 3. Evaluate the utility and accuracy of the cone results as a means to assess conventional soil properties; and, 4. Conduct a preliminary evaluation of the cone results in the context of recently developed methods to predict liquefaction potential. The work in regard to the first objective involved assembling and writing software for a microcomputer based data acquisition system. Successful implementation of this system allowed data from the tests to be rapidly processed and displayed. Calibration tests with the cone were carried out in a four foot high model bin which was filled ten times with sand formed to variety of densities. The sand used is Monterey No. 0/30, a standard material with well known behavioral characteristics under static and dynamic loading. The test results showed the cone to produce consistent data, and to be able to readily distinguish the varying density configurations of the sand. Using the results in conventional methods for converting cone data into soil parameters yielded values which were consistent with those expected. Liquefaction potential predictions were less satisfying, although not unreasonable. Further research is needed in this area both to check the reliability of the prediction procedures and the ability to achieve the desired objectives. / M.S.

Thesis (MScEng.)--University of Stellenbosch, 2001. / ENGLISH ABSTRACT: The last two decades have seen many changes within the automotive industry. Many advances have been made in the design, research and development of the internal combustion engine and technological progress made in the integrated-circuit and computer industry has resulted in the availability of reliable low-cost electronic components. These components have, over time, been incorporated into the very hearts of engines, thereby allowing for the accurate control of engine functions and processes to an extent that was previously impossible. Parallel to these developments is the growing concern for the environment and the realisation that resources are being consumed at ever-increasing rates. This has placed vehicle manufacturers under continual pressure to optimise their engines, not only for fuel efficiency, but also to reduce harmful emissions while continuing to deliver better performance and drivability characteristics. At the same time, engine testing equipment and facilities have had to keep abreast with these advances and this has required the development of more sophisticated testing facilities. One such facility is the dynamic engine test-bed. Among other features, this facility has the ability to subject test-bed mounted engines to loads similar to what would be experienced in a vehicle on the road. This approach allows for the optimisation of engine components and performance under more realistic conditions, yielding results far superior to those obtainable using more conventional steady-state testing and development procedures. This document discusses the development of such a dynamic engine test-bed at the Centre for Automotive Engineering at the University of Stellenbosch. The project was initiated by conducting a literature survey to establish the current state of technology in the field. The dynamic test-bed was developed around an existing direct-current electric motor and industrial speed controller configured in a regenerative manner. This setup enabled the unit to both absorb and deliver power, essential for the simulation of vehicle dynamics. Great care was taken to ensure that signals obtained from the test-bed were accurate and useful for further computer manipulation. Anti-aliasing filters were designed and manufactured to guarantee that signals could not be misinterpreted due to sampling effects. A computer-implemented vehicle model was developed to simulate, in real-time, vehicle response to torque developed by the engine on the test stand. The model included a manual transmission, clutch and a rigid drive-shaft. Driver input (accelerator, brake, clutch and gear selection) was by means of a set of pedals and hand-held gear selector switches. Various vehicle speed control strategies were investigated and recommendations made regarding their possible future implementation. System evaluation was accomplished by the simulated acceleration of a large truck. The simulations indicated that repeatable results could be obtained from the system. The system was also found to be adequately sensitive to reflect the effect of subtle changes made to engine parameters on vehicle acceleration. It was concluded that the dynamic engine test-bed did indeed offer the capability to conduct research and testing not previously available in South Africa. Finally, recommendations were made for the future improvement and expansion of the system's performance and capabilities. / AFRIKAANSE OPSOMMING: Die laaste twee dekades het baie veranderinge in die outomobiel industrie megebring. Groot vooruitgang is gemaak in die ontwerp, navorsing en ontwikkeling van die binnebrand enjin, terwyl tegnologiese vooruitgang in die geïntegreerde-stroombaan en rekenaar industrië betroubare elektroniese komponente teen lae koste beskikbaar gemaak het. Hierdie komponente is mettertyd in enjins geïnkorporeer en het die akkurate beheer van enjin funksies en prosesse moontlik gemaak. Saam met hierdie ontwikkeling, is daar toenemende kommer oor die omgewing en 'n bewuswording dat hulpbronne verbruik word teen 'n groeinde tempo. Hierdie feite plaas voertuig vervaardigers onder volgehoude druk om enjins te optimeer vir brandstof doeltreffendheid, maar ook om skadelike emissies te bekamp terwyl beter werksverrigting en bestuurbaarheid vereis word. Enjin toetstoerusting en fasiliteite moes terselfdetyd met hierdie vooruitgang byhou en het die ontwikkeling van meer gesofistikeerde toetsfasiliteite vereis. Een sodanige fasiliteit is die dinamiese enjin toetsbank. Een van die kenmerke van hierdie fasiliteit is dat dit toetsbank-gemonteerde enjins kan onderwerp aan 'n las soortgelyk as wat ondervind sou word in 'n voertuig op die pad. Hierdie benadering stel ingenieurs in staat om enjin komponente en werksverrigting te optimeer onder meer realistiese kondisies en lewer resultate van 'n baie hoër gehalte as wat verkry kan word deur gebruik te maak van meer konvensionele gestadigde-toestand toets- en ontwikkelings-prosedures. Hierdie dokument bespreek die ontwikkeling van so 'n dinamiese enjin toetsbank by die Sentrum vir Automobielingenieurswese aan die Universiteit van Stellenbosch. Die projek is geïnisieer deur 'n literatuurstudie te doen om die huidige stand van tegnologie in die gebied vas te stel. Die dinamiese enjintoetsbank is ontwikkel rondom 'n bestaande gelykstroom-motor en industriële spoed beheerder wat in 'n regeneratiewe konfigurasie opgestel is. Hierdie opstelling het die absorpsie en lewering van drywing moontlik gemaak, 'n vereiste vir die simulasie van voertuig dinamika. Baie tyd is gespandeer om te verseker dat seine afkomstig van die toetsbank akkuraat en bruikbaar was vir verdere rekenaar manipulasie. Anti-aliaseringsfilters is ontwerp en vervaardig om te verseker dat seine nie verkeerd geïnterpreteer kon word as gevolg van diskritiserings effekte nie. 'n Rekenaar ge-implementeerde voertuigmodel is ontwikkel om 'n voertuig se reaksie op draairnoment ontwikkel deur die enjin op die toetsbank intyds te simuleer. Die model het 'n handrat transmissie, koppelaar en starre dryf-as ingesluit. Bestuurder intree (vernellingspedaal, rem, koppelaar en rat seleksie) is bewerkstellig deur middel van 'n stel pedale en 'n hand geoperateurde rat skakelaar. Verskeie voertuig spoed-beheerders is ondersoek en aanbevelings is gemaak aangaande die toekomstige implementering daarvan. Die sisteem is geëvalueer deur die versnellingsimulasie van 'n groot vragmotor. Die simulasies het daarop gedui dat herhaalbare resultate van die sisteem verkry kon word. Daar is ook bevind dat die sisteem sensitief genoeg was om subtiele veranderinge aan enjinparameters in die resultate te weerspieël. Die gevolgtrekking is gemaak dat die dinamiese enjin toetsbank inderdaad die vermoëns gebied het om ontwikkeling en toetswerk te doen wat nie voorheen in Suid-Afrika moontlik was nie. Voorstelle is laastens gemaak aangaande die toekomstige verbetering en uitbreiding van die sisteem se vermoëns.