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The objective of the study was to map the structure of the construction engineering and management (CEM) discipline and its contents, trace its evolution, and to identify the most prevailing research areas in the discipline. The study entailed a review of the literature in construction engineering and management as well as two of the leading academic journals in the discipline, particularly a bibliometric study of the contents of the ASCE Journal of Management in Engineering (JME), as a case study of the CEM refereed journals. The JME's contents were investigated from its onset in 1985 until 2002. The results of the analysis show that 70% of the published papers focused on four main subjects: management and organization of the firm, project management, industry structure and environment, and management of personnel. Considerable changes occurred within the subjects with the emergence of new topics and the decline of others over the eighteen years of publication. The study also analyzed the use of keywords, research methods, and identified authors, and the concentration of knowledge. The JME is mainly concerned with the managerial aspects of engineering, while ASCE Journal of Construction Engineering and Management (JCEM) focuses more on construction and technical issues. Additional studies of the JCEM's contents should be conducted for a complete mapping of the discipline in the USA.

Vegetable oil methyl esters obtained by transesterification of vegetable oils are considered to be suitable alternative fuels for diesel engines. However, higher viscosity, surface tension and boiling temperatures of biodiesels may adversely affect spray characteristics as compared to those of diesel. Thus, spray characteristics of Jatropha Methyl Ester (JME) are studied by comparing them to those of diesel in a high-pressure chamber with optical access to simulate the actual in-cylinder conditions. Also, the effect of inner-nozzle cavitation on JME and diesel sprays is studied by utilizing two nozzles, one with sharp entry-radius and the other with larger entry-radius. Finally, spray characteristics of surrogate fuels such as n-dodecane and n-hexadecane are also studied. The first part of the work concerning precise measurements of inner-nozzle geometry revealed that one of the nozzles has a hole diameter of 190-µm and entry-radius of around 70-µm, while the other has a hole diameter of 208-µm and entry-radius of around 10-µm. Injection rate-shape and coefficient of discharge for JME and diesel flow through the two nozzles were then measured. It was observed that while the coefficients of discharge (Cd) are almost identical for JME and diesel, the nozzle with entry radius of 10-µm exhibited around 20% lower Cd than that of the entry-radius of 70-µm. This observation coupled with insight from complementary CFD simulations of inner-nozzle flow showed that the lower Cd of the nozzle with entry-radius of 10-µm could be attributed to inner-nozzle cavitation. The second part of the work involved measurement of non-evaporating spray characteristics including spray-tip penetration, spray-cone angle and droplet size measurement under realistic operating conditions using techniques such as Shadowgraphy and Particle/Droplet Imaging Analysis (PDIA). The non-evaporating spray of the fuels are studied by injecting them using a common-rail fuel injection system into the high-pressure chamber maintained at room temperature. Experimental results show that JME is associated with a slightly faster spray-tip penetration and narrow spray-cone angle indicating inferior spray atomization which is confirmed by around 5% larger droplet sizes. Slower spray-tip penetration, wider spray-cone angle and around 5% smaller droplet sizes are observed for the spray from the cavitating nozzle. Thus, the inner nozzle cavitation is observed to improve the atomization of diesel and JME sprays. The differences in spray characteristics of JME and diesel reduce as the injection pressure increases. The spray-tip penetrations of both surrogates are observed to almost match that of diesel. The third part of the work involved measurements of evaporating spray liquid length, vapour penetration and spread angle for JME, diesel and surrogates at conditions of 50 bar chamber pressure and 900 K temperature. It is observed that the JME exhibits around 16% longer liquid length than that of diesel. The liquid length of n-dodecane is significantly lower than that of diesel and liquid length of n-hexadecane is around 20% higher than that of n-dodecane mimicking the trend of JME and diesel. The liquid length of n-hexadecane is very close to that of diesel at all the three test conditions. Interestingly, the vapour penetration and spread angle for all the fuels is observed to be almost identical. As the cold spray and evaporating spray characteristics of n-hexadecane match well with those of diesel, n-hexadecane can be chosen as a pure component surrogate for diesel. Finally, an analytical model for predicting the spray vapour penetration is assessed with the experimentally-observed trends of penetration and spray spread angle. The model indicated that the effect of fuel density variation is compensated by the corresponding variation in injection velocity for a given injection pressure to result in a similar vapour penetration. Overall, the present work, in addition to studying the effect of fuel physical properties and cavitation on sprays, has generated a comprehensive experimental database on non-evaporating and evaporating sprays of biodiesel, diesel, and pure component surrogates, which would aid significantly in validation of CFD simulations.

This master's thesis deals with the possibilities of using open source 3D game engine Java Monkey Engine (jME) in developing applications for the Android platform. It includes theoretical knowledge for the jMonkey Engine architecture and the Android platform. In the following section, the thesis describes used techniques and external libraries in solving issues of interaction between jME and Android platform and of working with objects in the 3D scene and their way of implementation.