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Register a new userStudy of Bulk Cargo Influence Upon Ship's Righting Lever
دراسة تأثير حركة الحمولات السائبة على ذراع عزم الاستعدال للسفينة
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Added by
Tishreen University ورقة بحثية
Publication date
2013
fields
Marine Engineering
and research's language is
العربية
Authors
هيثم عيسى( باحث )
Created by
Shamra Editor
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يقدم هذا البحث طريقة جديدة لحساب أثر انزلاق الحمولات السائبة عرضيا لسفن نقل الحبوب و تقييم أثرها على أمان السفينة بشكل دقيق جدا. يمكن تحديد تأثير انزلاق الحمولات في حال كانت العنابر محملة بحمولات مختلفة و بنسب ملء مختلفة. يمكن تقييم هذا الأثر كميا من خلال رسم منحني ذراع عزم الاستعدال المحصّل. نقدم وفق هذه الطريقة مخطط زوايا مميزة خاصة بعملية الانزلاق، هذا المخطط يتم اقتراحه للمرة الأولى بحيث يقدم صورة شديدة الوضوح عن كل مرحلة من مراحل ميلان السفينة عرضيا نحو اليمين أو نحو اليسار.
This paper presents a new method for studying the bulk cargo behavior and its effects on righting lever. Effects of cargo sliding in holds are computed for each heel angle. The deficiency of righting lever is quantitatively computed and plotted on the designed application windows. For the first time a three characterizing angles are presented here, what offer a new clear vision about the cargo sliding steps.
References used
Captain J Isbester "BULK CARRIER DESIGN PRINCIPLES AND CRITERIA ", 16th INTERNATIONAL SHIP AND-OFFSHORE STRUCTURES CONGRESS-20-25 AUGUST 2006. SOUTHAMPTON, UK, 01-25
AUGUST 2006. SOUTHAMPTON, UK, 01-25. 2 BIRAN, A. B., “Ship Hydrostatics and Stability”, Butterworth-Heinemann, London, 2003, 141-142
DERRETT, D.R., “Ship Stability for Masters and Mates”, Butterworth-Heinemann, OXFORD, 2006, 266-275
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In order to calculate the cross curve of stability related to ship form the water line
of equal volume corresponding to each load draught should be determined. Therefore
complex and long steps of mathematical calculations should be done for each ve
ssel
displacement.
The goal of this research is to build a mathematical model enables the determination
of cross curve of stability related to ship form for all ship displacements. This model is
based on reading of the transverse sections of the ship projected on to a vertical transverse
plane of the body plan.
This method does not need to previous assumptions to perform calculations therefore
the calculations accuracy could be increased in comparison with other methods currently in
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The efficiency of this method has been proven in saving time as well as in giving
good results by comparing it with the analytical results for ships of box and trigonometric
forms. The comparison includes Pozduinin approximate method which is largely used in
ship world as well as the stability curves for real commercial ship. The good results of
evaluation of cross curves of stability by the proposed method (scanning sections method)
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100 samples of some tradional ice cream sold in Damascus to customers
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The study showed that the rate of rejection for Syrian normal standard was
85.
71 % for coliform, 9.89 % for Staph. aureus and 0 % for Salmonella .
In addition to identification of E.coli often found in ice cream there were
Enterobacter cloacae, Klebsiella planticola or Klebsiella oxytoca and to less
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on bulk density and structure stability for clay soil has taken from
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The main achieved results in this study showed , a significant
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