Application of the reliability of repairable systems on solving problems from constructing production systems takes an important place in the process of finding the optimal solution among the suggested system choices. The basic hypothesis when using the reliability of the repairable systems is that every machine is representing a component, a fact that is debatable when talking about technical sciences. However, considering the second assumption of the stationary process, the function of the availability is introduced. It represents the measure between (...) the reliability and the benefit of maintaining the components and the system as a whole one. An additional and the last reason for analyzing constructing machine as a whole one has an economic reason. From the aspect of the total cost and the capacity of the system, the function of the availability is catching more and more impact in the process of determinating the total cost in bill of quantities as the most important part of tender documents. Until former works, techno-economic optimisation usually ran over when choosing the system of the construction machines. In the work, there are shown the methodologies for gathering and analyzing the indicators of availabilities per unit of a company's machine park. The time of demission and reparation have been investigated among 34 components in the period of 6 years. Based on the obtained result for different conditions of machine exploitation and facilities, it is suggested the methodology of the future behaviour of the corresponding within the model optimization availability of constructing production system with the aim of eliminating extra criterion. The suggested model takes in consideration the total cost of the components when they are functional, and when they are not. This kind of approach enables the one who take choices decision of the height of profits, in the lenght of work in function of the projection of cash flow and managing with real indicators of functioning the system at the project level. Given the fact that the maintanance policy of machines is based on availability, and not on reliability of components, with the aim of maximizing the availability of different budget scenarios, a logical approach to the selection of the objective function in the terms of management of construction production systems is to minimize costs for a given availability of system constructing machinery is based on the use of historical data base with the values of the operational availability of components, conditions in which they function, in the process of forecasting the project availability for projects that follow. Ranking variant solutions is the result of the adopted function of the aim as a consequence due to enlargement methods of availability for serial parallel systems with the associated restrictions. For optimal system availability is taken a value that belongs to minimal total cost. However, it is predicted that after the end of the financial year, the real and projected indicators of system functions get compared to each other. Informational support to the proposed model is informational company system, which was built in the PHP programming language on the Linux software platform, and with data based in My SQL. The suggested model is tested on the system for the production and embedding bitumen bound materials on the specific project. Obtained results confirm the assumptions used in work. (shrink)

The Alberta tar sands, and the proposed pipelines which would carry their bitumen to international markets, comprise one of the most visible environmental controversies of the early twenty-first century. Jacques Ellul’s theory of technology presents ostensibly physical phenomena, such as the tar sands, as social phenomena wherein all values are subsumed under the efficient mastery of nature. The effect of technological rationality is totalizing because technical means establish themselves as the exclusive facts of the matter, which creates a socio-political (...) environment wherein ethical engagement is precluded. Analyzing the tar sands controversy through Ellul’s hermeneutic challenges environmental ethics to a more radical stance than the continuation of the technological worldview, and thus offers meaningful and hopeful alternatives to the status quo. (shrink)

The corpus of late antique Babylonian incantation bowls comprises a class of double-bowl sets, consisting of two bowls facing each other, fastened together with bitumen. Occasionally, such bowl sets have been found to contain inscribed egg shells or human bones. The double-bowl configuration is highly reminiscent of the double-jar burial practice attested in Mesopotamia from the second millennium to the sixth century BCE. The double-jar burial involved placing the deceased between two wide-mouthed jars, occasionally joining them with bitumen (...) at the rims. This article explores the double-bowl configuration and suggests a connection between double-jar burials and the later ritual artifacts of the Sasanian period. The double-bowl sets attached with bitumen may have originated on analogy to the ancient burial practice, intending symbolically to bury evil entities or human adversaries. (shrink)