Imam

This paper presents a comparison between different types of propellers operated in calm water to evaluate their performance behind hulls and in open-water conditions. A bulk carrier is chosen as a case study to perform the simulation and to evaluate the performance of several propeller series, namely the Wagengein B-series, Kaplan 19A, and MAU. Firstly, optimization procedures are performed by coupling a propeller design tool and a nonlinear optimizer to find the optimum design parameters of a fixed-pitch propeller. This optimization model aims to design the propeller behind the hull at the engine operating point with minimum fuel consumption and maximum propeller efficiency. The two main objectives of this study and the constraints are defined in a single fitness function to find the optimum values of the propeller geometry and the gearbox ratio. By considering the benefits of the single-objective over the multi-objective optimization problem, this model helps to find the optimum p...

For design of marine propeller, the energy supply from marine engine to the propeller should be converted to thrust force with minimum losses. Furthermore, the unwanted vibration and cavitation due to the overlooking a detail calculation of the propeller should be prohibited for increasing the fuel efficiency and life-span of the propeller. In the last few decades, most of small and medium sized enterprises (SMEs) focusing their work on ship component industry in Central Java Province Indonesia provide the marine propeller to the ship manufacturer and ship repairmen in some shipyards in northern part of Central Java port. The design of the propeller is never been observed and optimized. The aim of the present work is to redesign the installed propeller on a wooden fishing boat with the new optimized design using B-Series propeller theory approach. The reverse engineering method uses three-dimensional scanner to obtain the geometrical data of the installed ship propeller. The new opt...

As is known, adult education is the education that is given to individuals who are not in formal learning. And this takes place in the scope of continuing education. Teacher candidates undergoing teacher training have been prepared to teach at primary and secondary education. Being intellectual members of their societies, teachers are expected to be models for parents and other adults in the society. Within this scope, that they train and improve the surrounding adults is of essential. When looked through the programmes of faculties of education, it appears that there are mainly pupil-oriented lectures and activities. Thus we can easily say that preservice teachers cannot ready adequately for the adult education.In the light of such information, the key point is as fallows: “How are the preparatory competences of teacher candidates studying in faculties of education on adult education? ”. In order to solve the survey problem, the scanning model have been used. Data concerning the pr...

This paper presents a comparison between different types of propellers operated in calm water to evaluate their performance behind hulls and in open-water conditions. A bulk carrier is chosen as a case study to perform the simulation and to evaluate the performance of several propeller series, namely the Wagengein B-series, Kaplan 19A, and MAU. Firstly, optimization procedures are performed by coupling a propeller design tool and a nonlinear optimizer to find the optimum design parameters of a fixed-pitch propeller. This optimization model aims to design the propeller behind the hull at the engine operating point with minimum fuel consumption and maximum propeller efficiency. The two main objectives of this study and the constraints are defined in a single fitness function to find the optimum values of the propeller geometry and the gearbox ratio. By considering the benefits of the single-objective over the multi-objective optimization problem, this model helps to find the optimum p...

This paper presents a case study of repowering peculiarities in relation to an old vessel. The vessel selected for study was designed for cruising speed of 15 knots. Over the years of operation the vessel's cruising speed reduced to about 8 knots. So, the owner wanted to repower it to have a fresh tenure of life and the work was given to a shipyard. But after replacement of old two engines by new engines of same power with different model, the performance of the vessel was not satisfactory. In the present paper, the problem is studied with comprehensive calculations of hydrostatic particulars and resistance of the ship. The analysis is carried out in respect of engine specifications, gear ratios, propeller design etc. and found that the operating ranges of new engines are not at par with the old engines. The new engine does not also match with old propeller. At this situation, comparative studies have determined that among all possible solutions redesign of propeller is the most suitable one and cost effective.

The environmental problem in land activity created a big alarm especially close to very inhabited zones; in the marine field, after a very long period of stand by, the problem is felt mainly in the big water cities where, close to the harbours, a heavy microclimate expose people who live nearby to  risks of serious damages for their health. As well known, one of the main causes of air pollution in the harbours is the contemporaneous presence of many ships producing large amounts of noxious substances and the shore-side power supply of these ships is doubtless the better solution. Shore connection (also called “cold ironing ”) means to supply ships at berth in feeding points close to the mooring sites so that the diesel electric generators can be switched off and no exhausts are delivered during ship stay. A real standard solution for cold ironing is not available yet; actually, the kind of installation depends on the specific environmental and commercial vocation of the port as well...

A new practical method for improving the performance of a ship in waves had been established and showed favorable results in reducing the added resistance of a modified Wigley model at certain wavelength regions. In that method, optimization based on natural selection or socalled Genetic Algorithm (GA) was utilized and combined with the Enhanced Unified Theory (EUT) to compute the objective function during optimization. To illustrate effectiveness and efficiency of the method, in the present study, an actual ship e.g. SR-108 is used as a basis hull with the objective functions based on sensitivity study to the added resistance. The wave resistance is also computed in order to confirm reduction of the total resistance of such ship.

Everybody will agree that sea trial data is valuable. The value and usefulness of this information, however, can be greatly increased when the data is analyzed. Sea trial analysis is a critical process that can be used to provide a sense for how a boat is really operating. It can help fix problems when they appear, and better yet, it can be used in the design process of future boats to help avoid these problems from the outset. This paper tells the story of a boat that did not perform as expected. The various interested parties – the owner, builder, and propulsion equipment suppliers – all had different opinions about the performance and ways to improve it. The information presented here has been fictionalized to protect the interests of all parties, but it demonstrates how the information from a sea trial can be analyzed to expose what really is happening.

For design of marine propeller, the energy supply from marine engine to the propeller should be converted to thrust force with minimum losses. Furthermore, the unwanted vibration and cavitation due to the overlooking a detail calculation of the propeller should be prohibited for increasing the fuel efficiency and life-span of the propeller. In the last few decades, most of small and medium sized enterprises (SMEs) focusing their work on ship component industry in Central Java Province Indonesia provide the marine propeller to the ship manufacturer and ship repairmen in some shipyards in northern part of Central Java port. The design of the propeller is never been observed and optimized. The aim of the present work is to redesign the installed propeller on a wooden fishing boat with the new optimized design using B-Series propeller theory approach. The reverse engineering method uses three-dimensional scanner to obtain the geometrical data of the installed ship propeller. The new opt...

In the present paper the computational fluid dynamic (CFD) technique is applied to predict the total resistance (Rt) of Self Propelled Coal Barge (SPCB). The simulation process was executed using ANSYS®software based on fluid flow (CFX) solver. The selected CFD method is volume of fluid (VOF). The solid modeling of SPCB is developed using Maxsurf®. Boundary conditions are set on each domain area covering bottom , free surface , inlet , outlet , ship and wall . The variation of computaitional grid ( meshing grid ) which is used in computation are SST ( Shear Stress Transport )67,000, SST 73,000, SST 103,000, SST 117,000, SST 127,000, SST 147,000, SST 157,000, and SST 200,500. Total resistance (Rt) resulted from CFX computation is validated with total resistance (Rt) resulted from Holtrop. The larger of grid meshing size, the better of validation result. The CFD technique demonstrated good agreement with Holtrop formulae in predicting the total resistance (Rt) of SPCB.

One of the objectives of the eSAFE project was to develop a holistic probabilistic methodology, as well as an associated NAPA software functionality, for assessing post-damage ship survivability combining, through a sound and consistent generalised approach, collision, bottom grounding and side grounding/contact damages. This paper provides a summary overview of some main outcomes in this respect, namely: the development of a non-zonal approach for collision starting from, and extending, the SOLAS framework; the development and critical analysis of alternative approaches for considering the different attained indices from collision, bottom grounding and side grounding/contact damages; the practical implementation and testing of the framework.

The article presents a method to determine the route of a sailing vessel with the aid of deterministic algorithms. The method assumes that the area in which the route is to be determined is limited and the basic input data comprise the wind vector and the speed characteristic of the vessel. Compared to previous works of the authors, the present article additionally takes into account the effect of sea waves with the resultant resistance increase on the vessel speed. This approach brings the proposed model closer to real behaviour of a sailing vessel. The result returned by the method is the sailing route, optimised based on the multi-criteria objective function. Along with the time criterion, this function also takes into account comfort of voyage and the number of performed turns. The developed method has been implemented as simulation application SaillingAssistance and experimentally verified.

This thesis includes a concept design optimization which is applied on a new semi-submersible heavy transport vessel for Boskalis subsidiary Dockwise. Dockwise considers replacing four S-class semisubmersible heavy transport vessels which are nearing their end of lifetime. These relatively small size and low-end of the fleet vessels, transports a versatile and attractive market. The main objective of this thesis is to advice Dockwise on a new heavy transport vessel to replace the S-class vessels. The introduction of additional vessel functionality to increase market potential for heavy marine transport, logistical management and transport & installation services in relation to the current markets served by the S-class results in an initial concept that remains operational in the low-end of the market. Within this thesis, an investigation is done to economically analyse effective design add-ons of the initial concept to increase market potential. The current S-class is not capable of...

The author chanced upon an astoundingly simple way to obtain fuel efficiency even beyond the designed propeller performance. This article is to establish this claim. There is an immense waste of propulsive energy in the wake of the ships created by the propeller, in the bow waves and the froth around the ship, and due to cavitation in the propeller(s). The author has found a way to eliminate all these wastes of energy. The author has also applied the basic principle behind this improved efficiency in other similar settings where the transfer of energy between systems is involved, and similar improvements have been observed.

Ketidakseimbangan ketersediaan dan kualitas air minum diperkotaan yang cenderung menurun serta kebutuhan air yang semakin meningkat, diakibatkan karena padatnya penduduk dan banyaknya industri diperkotaan ditambah dengan pencemaran air oleh sampah, bakteri dan zat – zat berbahaya dari limbah industri. Untuk menghadapi hal tersebut banyak bermunculan pemasok atau depo – depo air minum isi ulang di daerah perkotaan. Namun pemilik depo air minum juga tidak bisa serta merta dalam menjual air minum isi ulang kepada konsumen. Karena perlu dilakukan pengecekan dan pemantauan dalam hal kualitas serta kuantitas (stok) air minum yang tesedia. Untuk proses pemantauan kuantitas atau stok air dan kualitas air masih dilakukan secara manual dengan melakukan pengecekan secara langsung. Hal iu membuat proses pengelolaan depo air minum isi ulang menjadi kurang efektif dan efisien. Untuk itu penelitian ini dilakukan guna membangun sistem kontroling dan monitoring kartu stok pada depo air isi ulang ber...

For design of marine propeller, the energy supply from marine engine to the propeller should be converted to thrust force with minimum losses. Furthermore, the unwanted vibration and cavitation due to the overlooking a detail calculation of the propeller should be prohibited for increasing the fuel efficiency and life-span of the propeller. In the last few decades, most of small and medium sized enterprises (SMEs) focusing their work on ship component industry in Central Java Province Indonesia provide the marine propeller to the ship manufacturer and ship repairmen in some shipyards in northern part of Central Java port. The design of the propeller is never been observed and optimized. The aim of the present work is to redesign the installed propeller on a wooden fishing boat with the new optimized design using B-Series propeller theory approach. The reverse engineering method uses three-dimensional scanner to obtain the geometrical data of the installed ship propeller. The new opt...

With the new harmonised regulations for damage stability, SOLAS 2009, now in place (since January 2009), a number of ship owners and consequentially yards and classification societies are venturing to exploit the new degrees of freedom afforded by the probabilistic concept of ship subdivision. In this process, designers are finding it rather difficult to move away from the prescriptive mindset that has been deeply ingrained in their way of conceptualising, creating and completing a ship design. Total freedom it appears is hard to cope with and a helping hand is needed to guide them in crossing the line from prescriptive to goal-setting design. This will be facilitated considerably with improved understanding of what this concept entails and of its limitations and range of applicability. This paper represents an attempt in this direction, based on the collective knowledge and experience of the authors, deriving from many years of research on damage stability and survivability and a s...

For design of marine propeller, the energy supply from marine engine to the propeller should be converted to thrust force with minimum losses. Furthermore, the unwanted vibration and cavitation due to the overlooking a detail calculation of the propeller should be prohibited for increasing the fuel efficiency and life-span of the propeller. In the last few decades, most of small and medium sized enterprises (SMEs) focusing their work on ship component industry in Central Java Province Indonesia provide the marine propeller to the ship manufacturer and ship repairmen in some shipyards in northern part of Central Java port. The design of the propeller is never been observed and optimized. The aim of the present work is to redesign the installed propeller on a wooden fishing boat with the new optimized design using B-Series propeller theory approach. The reverse engineering method uses three-dimensional scanner to obtain the geometrical data of the installed ship propeller. The new opt...

This paper surveys the relationship between Clergy Vocational Conflict, cognitive conflict (religious conflict and Quest) and psychological well-being in a sample of 178 Muslim clergy in Turkey. It was found that Clergy Vocational Conflict is accompanied by religious conflict and Quest. Those who experienced Clergy Vocational Conflict and religious conflict (but not Quest) suffered from poor psychological well-being. Quest, which does not affect psychological well-being, and religious conflict, which adversely affects it, are more common among the younger stratum of the sample. However, well-being prevails among the older layer and among the more educated clergy. Finally, psychological well-being, self-esteem, Quest and religious conflict were found as predictors for Clergy Vocational Conflict.

Intellektuelle har altid spillet en central rolle i den islamiske historie og ogsa i dag finder man muslimske intellektuelle i forskellige sammenhaenge. I en dansk kontekst har sadanne optradt i den offentlige debat fra sa forskellige udgangspunkter som for eksempel talsmanden for Hizbut-Tahrir, Junes Kock, imamerne fra Dansk Islamisk Center, Waseem Hussain, Naveed Baig og Fatih Alev, eller samfundsdebattorer med muslimsk baggrund som Tarek Ziad Hussein eller Ahmed Akkari. I det speciale, som ligger til grund for denne artikel, undersogte jeg en raekke danske muslimer, som jeg har valgt at kalde for de nye muslimske intellektuelle i Danmark. De udgor ikke en organiseret gruppe, men kender udmaerket hinanden. Det, som gor dem interessante, er, at de som nogle af de forste dansk opvoksede muslimer har erhvervet sig formelle islamiske uddannelser fra muslimske majoritetslande ved siden af deres uddannelser til ingeniorer, laeger og jurister. Pa baggrund af begge dele mener de, som musl...