International Journal of General Engineering and Technology

1-8

Authors: EHSANUL KABIR, HOSSEIN EMADI & MOHAMED Y. SOLIMAN

The minimum stem travel required to fully open an unbalanced, single-element Gas Lift Valve (GLV) is an important parameter in GLV performance calculations. The value of this parameter dictates whether the valve is fully or partially opened, thus determining the amount of gas passage through the GLV. The geometries of the ball and the seat are the main factors affecting this parameter. There exists only one equation in literature to readily calculate this minimum stem travel required for a fully open GLV. However, the derivation of this equation is based on only one position of the ball which might not be the case for different ball and seat geometries. Also, this equation allows to calculate the minimum stem travel for sharp-edge seats only. Recently, detailed theoretical calculations were made and experiments were run based on modified seat designs (beveled seats) (Elldakli, Soliman, Shahri, Winkler, & Gamadi, 2014) which showed a significant performance improvement compared to sharp-edge seats. As minimum stem travel depends on seat geometries, the existing equation cannot be applied for the beveled seats. In this paper, a set of new equations have been presented to calculate minimum stem travel for fully open GLV for any ball positions, and ball and seat geometry. In addition to the equation for sharp-edge seats, another equation has been derived for beveled seat based on average port area. This set of new equations is expected to make the relevant calculations more precise and correct.

1-6

Authors: SALAH ELDIN FARAG & MAGDY ALI ELASHKAR

The standard of education, training and evaluation has an important role in promoting the quality of seafarer’s competence. The International convention on standards of training, certification and watchkeeping for seafarers (STCW) together with the International Maritime Organization (IMO) model courses contain the required standard of competence for seafarers in light of emerging technologies. However studies of maritime accidents statistics show that the human factor is still the main originator of the problem. Hence there is a need to improve maritime education and training. This paper discusses the global standard of education, the maritime education systems in Egypt, the barriers and challenges to be addressed, the current and the proposed feature of the needs of the coming generation.

1-18

Authors: SARATH RAJ N. S & GEETANJALI R CHANDRA

Aviation safety affects everybody from governments, passengers, industry, freight companies and academic community. Over the years, aviation has been the safest mode of transport in the world but each casualty in air travel is entirely too many. This paper reviews the economic literature relating to aviation safety; examines aviation security as a growing dimension of aviation safety; and identifies emerging issues in airline safety and challenges for aviation safety research. Aviation safety needs to improve significantly, as the global population depends on an efficient and safe commercial network.

1-10

Authors: SALAH ELDIN FARAG

To impede substandard ships from cruising the seas and oceans of the globe, there is a safety net acting as filters or a gates. The first gate is the flag state which is considered the main gate to impede substandard ships from passing but those ships which endanger the safety of lives at sea and the marine environment found their way through the flag state gate via flag of convenience countries. The second gate is the classification societies gate which is of a great importance where there are more than 100 in the world only 12 of them are members in the International Association of Classification Societies (IACS). Flag states approve and delegate classification societies and Recognized Organizations (ROs) to carry out part of the role of the flag state under their supervision and responsibility. The third gate is a combination of ship owners, managing companies, ships masters and crew which also failed to impede substandard ships. The fourth gate is guarded by insurance companies and P & I clubs. The fifth gate is guarded by charterers, shippers and receivers. All the previous five gates failed to impede the passage of substandard ships that is why there was a need for a strong gate with overriding authority to prevent substandard ships from sailing, but that gate could not be globally but could be regional basis to be able to trace the ships through data bases. The new gate is guarded by Port State Control ( PSC ) which has become of ever increasing importance in the field of marine safety and marine pollution prevention and thus in the work of the International Maritime Organization (IMO) over the past few years. This paper reviews the role of the PSC, its goals and achievements over the years since its implementation till now and trying to find the answer of whether it achieved its goals or not by reviewing Paris MOU reports in 2013 and 2014. Finally discussing the reasons for PSC not achieving its goals and providing some recommendations which can improve the PSC performance.

8

Authors: CHRISTARAS V, MOROPOULOU AN, CHATZIANGELOU M, DIMITRAKI L & DEVLIOTI K

The non-destructive methods are necessary in the investigation of the physical and mechanical properties of the materials in monuments. In this framework the ultrasonic velocities were used in situ for the elaboration and evaluation of the weathering on the surfaces of monuments. Additionally, the P-wave velocities were used for the estimation of the depth of weathered zone, as well as the depth of cracks at the surface of the monument. This estimation was performed on a Jewish tomb placed in the AUTH university campus between the building of Law and Economic Sciences and the Administration building, of the Aristotle University of Thessaloniki.