World statistics proved that the most of work dangerous accidents, which causes death, are occurred in the construction works. These accidents related to many causes such as loss of workers experience and ignoring rules of safety requirements, especially young workers. Due to the risk of accidents that may occur in the site of work, the idea of this study crystallized to show the relationship between the age of worker and number of injuries and accidents, to identify the causes of these injuries, and to put the appropriate solutions to avoid or reduce the risk of work injuries. Also, the research shows the main principles of safety requirements to forming a clear picture about the subject of the study. A questioner form was prepared to collect the information and then analyzing it statistically in order to reach to the results and recommendations which contribute to decrease the occurrence of work injuries in the sites of construction projects.
Ge-Au infrared photoconductive detection was prepared from germanium single crystal which were doped with different gold concentration using thermal evaporation. The spectral resonsivity (Rλ), spectral detectivity (D*) were determined as function of wavelength, also the resistance, conductivity in dark and with illumination to infrared radiation, the gain and relative photo response have been measured with different gold concentration. Remarkable improvements in the photoresponse gain were observed for the highest resistance specimen at the expense of spectral detectivity values.
This paper reports on the experimental study, which conducted a series of triaxial tests for the asphalt concrete using hydrated lime as a mineral additive. Three HMA mixes, prepared by the specification for wearing, levelling and base layers, were studied under three different temperatures. The test results have demonstrated that, compared with the control mixes excluding HL, the permanent deformation resistance of the HL modified mixes has significant improvement. The deformation has been reduced at the same load repetition number, meanwhile the flow number has been considerably increased. The degree of improvement in permanent deformation resistance using HL is more pronounced at high stress deviation states and high temperature.
... Show MoreIn this work semi–empirical method (PM3) calculations are carried out by (MOPAC) computational packages have been employed to calculate the molecular orbital's energies for some organic pollutants. The long– chain quaternary ammonium cations called Iraqi Clays (Bentonite – modified) are used to remove these organic pollutants from water, by adding a small cationic surfactant so as to result in floes which are agglomerates of organobentonite to remove organic pollutants. This calculation which suggests the best surface active material, can be used to modify the adsorption efficiency of aniline , phenol, phenol deriviatives, Tri methyl glycine, ester and pecticides , on Iraqi Clay (bentonite) by comparing the theoretical results w
... Show MoreAt a time when any tourist in the world wants a trip to reload his energy and enjoy peace and quiet and engage in adventures in a safe environment, terrorism comes to disturb him on that journey through operations aimed at the tourist and entertainment destinations, such as shops, restaurants, cafes and hotels Is the orbit of research) for many reasons. The security measures taken by hotels play an important and fundamental role in preventing or limiting these terrorist operations. At the same time, while some hotel administrations are constantly seeking to improve these measures to preserve the safety of their guests and visitors, In spite of the high number of attacks on hotels since 2001 and today. This research is intended to highlight
... Show MoreThe objective of this study is to determine the efficacy of class V Er:YAG laser (2940 nm) cavity preparation and conventional bur cavity preparation regarding Intrapulpal temperature rise during cavity preparation in extracted human premolar teeth. Twenty non carious premolar teeth extracted for orthodontic purposes were used and class V cavity preparation was applied both buccal and lingual sides for each tooth .Samples were equally grouped into two major groups according to cavity depth (1mm and 2mm). Each major group was further subdivided into two subgroupsof ten teeth for each (twenty cavities for each subgroup). TwinlightEr:YAG laser (2940 nm) with 500mJ pulse energy, P.R.R of 10 Hz and 63.69 J/cm2 energy density was used. The ana
... Show MoreFlexible pipes, such as GRP pipes, serve as effective underground infrastructure especially as sewer pipeline. This study is an attempt for understanding the effects of bedding types on the behavior of large diameter GRP flexible sewer pipes using three dimensional finite element approaches. Theoretical and numerical analyses were performed using both BS EN 1295-1 approach and finite element method (ABAQUS software). The effects of different parameters are studied such as, depth of backfill, bedding compaction, and backfill compaction. Due to compaction, an increase in the bedding compaction modulus (E’1) results in a reduction of both stresses and displacements of the pipe, especially, for well compacted ba
... Show MoreThis study aims to evaluate and compare the cytotoxicity and biocompatibility of a modified heat-cured acrylic denture base material containing 15% phosphoric acid 2-hydroxyethyl methacrylate ester (PA2HEME) with those of nonmodified PMMA. Discs with a diameter of 12 mm and a thickness of 2 mm were prepared using a heat-cured PMMA denture base material and divided into control and experimental groups. The experimental group was modified with 15% phosphoric acid 2-hydroxyethyl methacrylate ester (PA2HEME). The modified and nonmodified materials were tested via FTIR, and the effect of modification on surface roughness was evaluated with AFM. An in vitro test was conducted to examine the cytotoxicity and biocompatibility of heat-cured acry
... Show MoreThis study investigates the impact of varying glass fiber-reinforced polymer (GFRP) stirrup spacing on the performance of doubly GFRP-reinforced concrete beams. The research focuses on assessing the behavior of GFRP-reinforced concrete beams, including load-carrying capacity, cracking, and deformability. It explores the feasibility and effectiveness of GFRP bars as an alternative to traditional steel reinforcement in concrete structures. Six concrete beams with a cross-section of 300 mm (wide) × 250 mm (deep), simply supported on a 2100 mm span, were tested. The beams underwent four-point bending with two concentrated loads applied symmetrically at one-third of the span length, resulting in a shear span (a)-to-depth (h) ratio of 2.
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