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The paper analyzes geopolitical circumstances on the global oil market towards the beginning of the 21st century. After the oil price leap, the global oil market has entered the phase of possible energy-related crises, political instability and major disturbances. Such a condition makes the energy-related situation of energy importers rather difficult, especially when it comes to relatively small countries outside of geopolitical integrations, but also makes the need for energy savings topical once again, along wi...

The utilization possibilities of secondary raw materials in civil engineering are presented in this paper. Three various solid waste kinds were tested as a partial cement or natural aggregate material replacement in construction applications. The influence of mechanically and chemically activated coal fly ash as 25 wt. \% cement replacement and steel slag and recycled concrete as aggregate fraction replacement on compressive strength development of composites during hardening was investigated. The addition of the ...

The preliminary goal of this study is to design, construct and test an automatic sequential precipitation sampling instrument. Testing includes collection of sequential precipitation samples, analyzing them and trying to find the sources of environmental pollution. Proposed sequential sub-event sampler is composed of two parts; mechanic and electronic hardware. Mechanical part includes a stepped 100 ml sampler cups on it, and a metallic body. Electronic part is composed of digital and analog sensors, various elect...

Stress intensity factor is the one of most important parameters in rock fracture mechanics. In practice, this factor is commonly calculated by various numerical techniques such as finite element and boundary element methods. These methods encounter mesh-related difficulties in dealing with fracture mechanics problems. In this paper the Element Free Galerkin method based on the linear elastic fracture mechanics was used to determine tension-mode stress intensity factor in jointed rock medium using stress extrapolat...

The process of rock massif separation with the method of rotary drilling is a dominant process in geotechnology and in subterranean raw material mining. The type of drilling tool used and the mode of drilling with given properties of the rock are crucial in the determination of energy efficiency of this process. The research is directed toward classification of rocks into classes (pattern classification) according to geomechanical properties and the determination of efficient mode of drilling for individual define...

The world is being polluted rapidly in recent years. Pollution, which can stem from both natural and artificial causes, has a detrimental effect on our health and the environment. People’s contribution to the pollution cannot be emphasized enough. Technological development also plays an important role in environmental pollution. Extravagant uses of technology and people’s lack of sensitivity to the damages of technology cause pollution to increase in an uncontrollable rate. Pollution causes both global warming and...

Mudstone formation samples from Crete, GREECE are investigatedwith regard to their suitability as raw materials for rammed earth and adobe production. This paper deals with the mineralogical composition, soil particle size distribution of samples, as well as the analysis of sample consistency and compressive strength of rammed earth cube samples. Quartz and clay minerals are the major mineralogical constituents, whereas micas, chlorites, iron-oxides and hydroxides, carbonates and feldspars were detected in various...

Industrial processes do not get full efficiency and this means that a considerable amount of wastes without economical aim and which will finish in rubbish dumps, hence promoting a large environmental impact. Modern society steer itself, towards getting a sustainable development which minimize the production of these wastes, which are also increasing its economical, environmental and social costs. This fact compels to search solutions which could avoid the generation of this kind of wastes and to get value from th...

Defining the mineral potential of the sea floor could be handled by different methods, but the prerequisites for each methods is to clear the conditions of precipitation environment such as physico – chemical conditions and also it depends on the type of precipitant. The appearance of any mineral in the sea floor strongly depends on the aqueous environment and the physical prosperities of the mineral. In this article, first of all, I considered the physiographic regions of the sea floor in entire the world, an acc...