scholarly journals Remedial Solutions to Control Excessive Propeller Induced Hull Vibrations on a Landing Craft

2018 ◽  
Author(s):  
M Fan ◽  
B Aktas ◽  
W Shi ◽  
N Sasaki ◽  
P Fitzsimmons ◽  
...  
Keyword(s):  
Arabian Gulf ◽  
Flow Conditions ◽  
Power Performance ◽  
Gulf Region ◽  
Cfd Simulations ◽  
Flat Bottom ◽  
Hull Form ◽  
Propulsive Efficiency ◽  
Arabian Gulf Region ◽  
Computational Fluid Dynamics Cfd

Although landing craft are not sophisticated vessels, their functional/operational requirements often result in a hull shape which may encounter unusual hydrodynamic phenomena, requiring remedial attention. One such instance is discussed in this paper, which presents hull form solutions adopted to address excessive vibration experienced on-board an enhanced landing craft operating in the Arabian Gulf region. Through Computational Fluid Dynamics (CFD) simulations, the sources of excessive vibration experienced by this vessel were identified. The sources included the current bow design, which promoted aeration; an extensive flat bottom, which channelled the air to a shallow buttock-flow stern region; angled pram type stern fitted with blunt-ended appendages generated a non-uniform flow that was too severe for the existing propeller-hull clearances. The combination of these unfavourable flow conditions with the cavitating propellers resulted in undesirable Propeller-Hull Vortex Cavitation (PHVC) which manifested itself with excessive aft end vibrations and noise. To remedy the situation and to control the excessive vibrations, further CFD simulations guided the necessary hull form modifications. The identified countermeasures included anti-Propeller Hull Vortex (PHV) plates and streamlining of stern appendages. Subsequent sea trials showed horizontal vibration levels were reduced by 85%, which significantly improved the conditions on-board. This paper presents a technical summary of the above countermeasures, their implementations on the vessel, which included full-scale trials to measure the speed-power performance, hull vibrations and cavitation observations using a borescope system, and discussions of the results of these countermeasures. The paper concludes with an outline proposal for further design study, which could reduce on-board vibrations even further as well as providing other operational benefits regarding propulsive efficiency and manoeuvrability using the recently developed “Gate Rudder System ®” as a novel Energy Saving Device (ESD).

Branding of Germany’s Transnational Education and its Potentials in the Arabian Gulf Region

2018 ◽  
Vol 2 (3) ◽  
Author(s):  
Sanaa Ashour
Keyword(s):  
Higher Education ◽  
Arabian Gulf ◽  
Current Debate ◽  
Transnational Education ◽  
Gulf Region ◽  
Demand For Education ◽  
Financial Gain ◽  
Arabian Gulf Region ◽  
Global Demand ◽  
Foreign Education

Transnational education (TNE), responding to the growing global demand for education, plays a fundamental role in the current debate on the internationalisation and globalisation of higher education. Conducting a systematic literature review, this paper examines the characteristics of German transnational education, which has little in common with the American and British models, the reasons for its limited presence in the Gulf and its potential for having a stronger footprint. Since education for Germany is a public good, financial gain has never been a decisive factor for German universities to venture abroad. Whilst the Gulf Region is the largest importer of foreign education, German TNE is only represented by one university there, compared to the overwhelming number of US, UK and Australian higher education institutions. Although the Gulf Region is considered as a lucrative and appealing market for foreign education, lack of engagement of German TNE there could be interpreted through public policy-related reasons. Since Germany has already established its footprint in creating a unique brand of TNE, the paper recommends to build upon the country’s expertise in low-risk option for Germany to invest in the Gulf. For this to materialise, Germany must build awareness of its unique brand to stand out among the competition. 

Web Accessibility Research and Practice

2021 ◽  
Vol 10 (1) ◽  
pp. 36-49
Author(s):  
Mona M. Alnahari ◽  
Joyram Chakraborty ◽  
Mona Mohamed
Keyword(s):  
Arabian Gulf ◽  
Web Accessibility ◽  
Gulf Region ◽  
Persons With Disabilities ◽  
Research And Practice ◽  
Wcag 2.0 ◽  
Arabian Gulf Region ◽  
The World ◽  
Accessibility Issues ◽  
Arabic Speaking

Web accessibility is the practice of having websites that are accessible to all people, including persons with disabilities. Several research studies have been done around the world to improve web accessibility. However, advances in Arabic web accessibility studies are limited. Research has indicated that a significant number of Arabic websites have accessibility issues, which becomes a restraint to people with disabilities from accessing and using the web. This research reviews current studies in web accessibility presented within the cultural background of several Arabic-speaking countries, particularly the Arabian Gulf region of Gulf Cooperation Council, and addresses services offered by the countries. The authors evaluate 54 websites in the Gulf region regarding accessibility issues. The results show that all websites do not satisfy WCAG 2.0 (AA). This paper highlights the deficiencies in Arabic web accessibility and provide some recommendations and suggestions for improvements.

scholarly journals Diet and Food Allergy as Risk Factors for Asthma in the Arabian Gulf Region: Current Evidence and Future Research Needs

2019 ◽  
Vol 16 (20) ◽  
pp. 3852 ◽  
Author(s):  
Naser A. Alsharairi
Keyword(s):  
Risk Factors ◽  
Food Allergy ◽  
Eastern Mediterranean ◽  
Arabian Gulf ◽  
Current Evidence ◽  
Future Research ◽  
Gulf Region ◽  
Arabian Gulf Region ◽  
Mediterranean Countries ◽  
Increased Risk

Asthma is a chronic respiratory disease which is associated with higher levels of systemic inflammation. The causes of asthma remain poorly understood. Unhealthy diet and food allergy are potential risk factors for developing asthma. The prevalence of asthma in the Arabian Gulf region (AGR), and Kuwait, Saudi Arabia and Qatar in particular, is higher than in other Eastern Mediterranean countries. In the AGR, diets tend to be of low nutritional value due to high levels of total energy, cholesterol, sodium, added sugars and saturated fat, and low levels of fiber, fruit and vegetables. A few studies that include children and adults in the AGR have suggested a potential link between unhealthy diets/specific food allergens and increased risk of asthma, however, the association of food allergy with asthma is still a controversial issue. The aim of this commentary is to consider the evidence from the AGR regarding the effects of diet/food allergy on asthma risk that may be used to make recommendations for future research.

Sign in / Sign up

Export Citation Format

Share Document