572 research outputs found

    Causative factors of cost overrun in highway projects of Sindh province of Pakistan

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    Cost overrun is an increase of cost of project from approved budget which was signed by parties at the time of tender. Cost overrun in construction of highway projects is a common problem worldwide and construction industry of Pakistan is also facing this crucial problem of cost overrun in highway projects of Pakistan. The main objective of this research is to identify the causative factors of cost overrun in highway projects of Sindh province of Pakistan. A well designed questionnaire was developed based on 64 common factors of cost overrun from literature review. Developed questionnaire was distributed among selected 30 experts from owner/client, designer/consultant and contractor who have experience more than 20 years’ experience in highway projects. The collected data was statistical analyzed. After analysis results showed that delay process in payment by client, inadequate planning , client interference, poor contract management, delay of decision making, change of scope of project and financial problems faced by client were most causative factors of cost overrun in highway projects. This research will provide alertness to stakeholders of highway projects of Sindh province to avoid cost overrun in projects

    NAKED EYE ESTIMATES OF MORNING PRAYER AT TUBRUQ OF LIBYA

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    Naked eye observations at Tubruq sky (φ = 32° 05´, λ = 23° 59´) in Libya at the Mediterranean coast (see-desert background) during the two years (2008 – 2009) of morning twilight have been recorded.  These observations led us to get some estimates about morning twilight, as it is necessary to determine the time of the True Dawn (Al-Fajr Prayer Time).  this research aims to determine the correct time of Al-Fajr Prayer by finding the accurate angle of the sun vertical depression below the horizon that is associated with legitimate mark. The Methode used in this research was field research while the observations have been recorded by monitoring the first white thread on the eastern horizon (True Dawn) that announces the time of the Morning Prayer (Al-Fajr Prayer).  The azimuthally range of observation about the solar vertical extends from 0° up to ±20°, while the phenomenon was followed from 0° up to 20° along the altitudinal range.  This research gives a result that a beginning of the morning twilight is estimated to be around 13.5° depression of the sun below the horizon.  This value can reach a minimum depression around 11.5° at low visibility and a maximum around 13.5° at a very god visibility

    NAKED EYE ESTIMATES OF MORNING PRAYER AT TUBRUQ OF LIBYA

    Get PDF
    Naked eye observations at Tubruq sky (φ = 32° 05´, λ = 23° 59´) in Libya at the Mediterranean coast (see-desert background) during the two years (2008 – 2009) of morning twilight have been recorded.  These observations led us to get some estimates about morning twilight, as it is necessary to determine the time of the True Dawn (Al-Fajr Prayer Time).  this research aims to determine the correct time of Al-Fajr Prayer by finding the accurate angle of the sun vertical depression below the horizon that is associated with legitimate mark. The Methode used in this research was field research while the observations have been recorded by monitoring the first white thread on the eastern horizon (True Dawn) that announces the time of the Morning Prayer (Al-Fajr Prayer).  The azimuthally range of observation about the solar vertical extends from 0° up to ±20°, while the phenomenon was followed from 0° up to 20° along the altitudinal range.  This research gives a result that a beginning of the morning twilight is estimated to be around 13.5° depression of the sun below the horizon.  This value can reach a minimum depression around 11.5° at low visibility and a maximum around 13.5° at a very god visibility

    Diacritical Seismic Signatures for Complex Geological Structures: Case Studies from Shushan Basin (Egypt) and Arkoma Basin (USA)

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    Seismic reflection techniques show an imperative role in imaging complex geological structures and are becoming more acceptable as data interpreting tools in 2D/3D view. These subsurface geological structures provide complex seismic signature due to their geometrical behavior. Consequently, it is extremely difficult to interpret these seismic sections in terms of subsurface configuration. The main goal of this paper is to introduce seismic attributes as a powerful tool to interpret complex geological structures in different geological settings. In order to image these complex geological features, multiple seismic attributes such as coherence and curvature have been applied to the seismic data generated over the Shushan Basin (Egypt) and Arkoma Basin (USA). Each type of geological structure event usually generates a unique seismic “signature” that we can recognize and identify by using these seismic attributes. In Shushan Basin (Egypt), they provide a framework and constraint during the interpretation and can help prevent mistakes during a 3D structural modeling. In Arkoma Basin (USA), the seismic attributes results provide useful information for broader analyses of the complex structural relations in the region where the Ouachita orogenic belt intersects with the southern Oklahoma aulacogen. Finally, complex geological structures provide dramatically diacritical seismic signatures that can be easily interpreted by collaborating conventional seismic interpretation techniques with multiple seismic attributes

    Pengaruh Tepung Cangkang Rajungan (Portunus pelagicus) dalam Ransum terhadap Kadar Kolesterol Serum dan Pertambahan Bobot Badan Tikus Putih (Rattus norvegicus)

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    Crab shells contain the highest percentage of chitin. Chitin and its derivatives have many properties that make them attractive for a wide variety of applications. This study was conducted to determine the effect of crab (Portunus pelagicus) shells as a source of chitin in ration on serum cholesterol and weight gain of rats (Rattus norvegicus). The study was carried out in a factorial experiment 2 x 5 with 3 replications. The first factor is sex and the second factor is crab shells of 5 levels i.e., 0%, 5%, 10%, 15%, and 20% in ration. The study showed that there were no interaction effect between sex and crab shells levels in diet on all parameters. Serum cholesterol levels decreased (P > 0.05) and weigh gain increased (P < 0.01) when crab shells were included in the diets. The highest reduction of serum cholesterol level (14,8%) was observed at crab shells level of 10%, but the highest weight gain was reached at 5% inclusion of crab shells. These results suggest that crab shells in rat diets reduced serum cholesterol level and increased weight gain. Key words: crab shells, cholesterol, gain, ra

    Stability of Immediately Placed and Delayed Implants Using Resonance Frequency Analysis (RFA). A Systematic Review

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    Objectives: The aim of the present Systematic Review was to compare between immediate and delayed dental implant placement using resonance frequency analysis specifically Implant Stability Quotients (ISQ). Search methods: Search was performed in two databases (PubMed and Cochrane Library) till March 2023. Randomized clinical trials (RCTs) were included and measurements of ISQ at time of placement and time of loading were recorded. We excluded papers discussing bone grafting, orthodontic treatment and implant surface treatment. Results: Results were above ISQ threshold value of 65, with no significant difference between immediate and delayed implants. However, Immediate placement showed shorter treatment time and better esthetic outcome. Conclusion: Implant stability can be achieved with both immediate and delayed implant placement techniques

    Pengaruh Tepung Cangkang Rajungan (Portunus pelagicus) dalam Ransum terhadap Kadar Kolesterol Serum dan Pertambahan Bobot Badan Tikus Putih (Rattus norvegicus)

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    Crab shells contain the highest percentage of chitin. Chitin and its derivatives have many properties that make them attractive for a wide variety of applications. This study was conducted to determine the effect of crab (Portunus pelagicus) shells as a source of chitin in ration on serum cholesterol and weight gain of rats (Rattus norvegicus). The study was carried out in a factorial experiment 2 x 5 with 3 replications. The first factor is sex and the second factor is crab shells of 5 levels i.e., 0%, 5%, 10%, 15%, and 20% in ration. The study showed that there were no interaction effect between sex and crab shells levels in diet on all parameters. Serum cholesterol levels decreased (P > 0.05) and weigh gain increased (P < 0.01) when crab shells were included in the diets. The highest reduction of serum cholesterol level (14,8%) was observed at crab shells level of 10%, but the highest weight gain was reached at 5% inclusion of crab shells. These results suggest that crab shells in rat diets reduced serum cholesterol level and increased weight gain. Key words: crab shells, cholesterol, gain, ra

    Study on the tribological characteristics of plant oil-based bio-lubricant with automotive liner-piston ring materials

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    The development of bio-lubricant is an immerging area of research considering the rapid depletion of petroleum reserve and environmental concern. This study aims to develop non-edible jatropha oil-based bio-lubricant and investigate the tribological properties considering commonly used piston ring-cylinder liner materials of stainless steel and cast iron due to their interaction under lubricated conditions in an internal combustion engine. The bio-lubricant was prepared by blending different percentages of vegetable oil with commercial lubricants. The tribological test was carried out using a Reo-Bicerihigh-frequency reciprocating rig (HFRR) for the duration of 6 ​h under standard operating conditions. Different properties of bio-lubricants were measured before and after the HFRR test using various analytical instruments. The morphology of the worn material surfaces was examined via Hitachi S-4700 FE-SEM cold field emission high resolution scanning electron microscopy (SEM). The result showed that addition of vegetable oil lubricant up to 7.5% concentration can be compared with commercial lubricant in case of wear rate and coefficient of wear as weight loss reduced significantly. Minimum change in viscosity was observed at the addition of 7.5% bio-lubricant. Surface morphology analysis confirmed less damage of metal surface when tribological analysis were performed at mixed lubricated condition. © 2022 The Author
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