Search results for "Civil engineering"
showing 10 items of 1216 documents
Considerations on the automation of a natural gas compressor station
2018
Natural gas compressor stations are very important components of a natural gas life cycle. Unfortunately, in Romania most of the existing natural gas compressor stations are equipped only with old-type automation systems, with a high degree of physical and moral wear. The current paper describes the main elements and functions of an automation system that was implemented in a natural gas compressor station, offering an improved pressure control function, but also the possibility to control the compressors from a distance, for example from a central dispatching station.
Developing adult motivation for continuous training
2021
Traditional education focused primarily on the moment of teaching, on the moment of transmitting information, knowledge, and only then on aspects related to ethical, motivational, moral nature. Contemporary society in a continuous remodeling and change, no longer coincides, no longer accepts such a system. Traditional learning does not keep pace with contemporary society. The aim of this study is to investigate the motivation of learning in adulthood. In the motivational structure of the investigated adults, extrinsic reasons predominated, indirectly related to the learning activity, such as: the need to advance professionally, to keep up with the times, to obtain a social status as high as…
Reinforcement Efficiency of Cellulose Microfibers for the Tensile Stiffness and Strength of Rigid Low-Density Polyurethane Foams
2020
Rigid low-density closed-cell polyurethane (PU) foams are widely used in both thermal insulation and structural applications. The sustainability of PU foam production can be increased by using bio-based components and fillers that ensure both enhanced mechanical properties and higher renewable material content. Such bio-based foams were produced using polyols derived from rapeseed oil and microcrystalline cellulose (MCC) fibers as filler. The effect of MCC fiber loading of up to 10 wt % on the morphology, tensile stiffness, and strength of foams has been evaluated. For estimation of the mechanical reinforcement efficiency of foams, a model allowing for the partial alignment of filler fibers…
The Geometry of a Domed Architecture: A Stately Example of Kārbandi at Bagh-e Dolat Abad in Yazd
2016
This paper analyses the kārbandi of the Hashti pavilion at Bagh-e-Dolat Abad in Yazd. Kārbandi is a spatial system obtained through the projection of a star-shaped drawing onto a curved surface. It is characterised by a complex use of geometry and repetitive symmetry. The analysis of its geometrical aspects contributes to an understanding of the traditional rules underlying the original design. The kārbandi of the octagonal vestibule of the Hashti pavilion consists of a complex roof system that completes the octagonal volume of the room below; its intrados presents a pattern of interlocking ribbed arches. The paper also looks at the drawings, module and proportions of the Hashti pavilion, w…
Are electric vehicles eco-friendly products? A review from life cycle and sustainability perspective
2021
Industry, especially the automotive industry is permanently changing and adapting to the external and internal factors. The appearance of the new types of vehicles – electric vehicles, is a big and important step not only regarding the evolution of the product, but also regarding the advantages of reducing environmental impact. It is promoted the idea that an electric vehicle generates less direct emissions in use phase compared with a conventional one. If we limit to this, we could say that we are dealing with an eco-friendly type of vehicle. The question is, can we extend this idea to the other stages of the life cycle? What about the sustainability of the industry? This article highlight…
Rubberised bitumen manufacturing assisted by rheological measurements
2015
This paper investigates the effect of processing temperature and time on the rheological proper- ties of recycled tyre rubber-modified bitumens (RTR-MBs) produced using two different base binders and an ambient ground crumb rubber modifier (CRM). The production of the RTR- MBs was accomplished by means of a standard Brookfield rotational viscometer together with a modified impeller, dual helical impeller, to allow mixing as well as real-time viscosity measurements of the produced RTR-MBs. The rheological properties of the final RTR-MBs were determined by means of standard dynamic mechanical analysis oscillatory and multiple stress creep recovery testing using a dynamic shear rheometer. The …
Bio-based rigid high-density polyurethane foams as a structural thermal break material
2020
Abstract Sustainable development of building industry implies increasing usage of green materials. With this aim and for the intended application as a structural thermal break material, rigid high-density polyurethane foams have been manufactured using polyols derived from renewable resources - tall oil fatty acids. Thermal conductivity, compressive strength and stiffness of the foams of density ranging from ca. 100 to 680 kg/m3 have been determined. Comparison of the bio-based foams with reference foams derived from petrochemical resources demonstrated similar performance characteristics thus suggesting that bio-based foams can also serve as structural thermal break materials. Analytical m…
Flexural Behavior of Glass Beams with T and I Shape Cross Sections
2017
AbstractGlass beams having T or I cross sections can be obtained as glass panels or laminated glass (LG) panels assembled with polymer adhesives of different types, such as semirigid (silicones, mo...
Natural gas hydrates vs. induced dysfunctions in the hydrocarbon extraction process
2021
Cantoned fluids in porous-permeable or fractured media of reservoirs have acquired during the geological time special properties. The fluids from the reservoir could be or not a mixture of reservoir water, liquid hydrocarbons and gaseous hydrocarbons. Considering if inside of a reservoir there are two types of substances like natural gas and reservoir water which may be in the form of vaporous than the condition of saturation of gases with water vaporous is fulfilled. This process is taking place due to thermodynamic equilibrium resulting the so-called gas humidity. This state corroborated with a certain chemical composition plus favourable values of pressure and temperature may be decisive…
Fundamental and practical aspects concerning the characterization of smart textiles
2017
The research aims towards a novel methodology of ZnO impregnation onto polyamide supports, in order to attain a special inorganic-organic hybrid polymer material, with increased UV-barrier attributes and high hydrophobicity. The experimental approach employed ZnO micro particles powder. Solutions with different concentrations of ZnO powder dispersed in methanol are prepared as anti-UV finishing agent and applied onto polyamide fabric. The responsive behaviour of this complex polymer network to UV irradiation, the photo protective performance and its time stability, also the hydrophobic character are assessed by different characterization techniques. The proposed method has advantages, like:…