간행물

Journal of Korean Navigation and Port Reserch KCI 등재 한국항해항만학회지

권호리스트/논문검색
이 간행물 논문 검색

권호

Vol.18 No.2 (1994년 5월) 10

1.
1994.05 서비스 종료(열람 제한)
Kwangyang harbour has been developed very rapidly and has 20 berths including 2 for 250,000DWT bulk carriers at the terminal of Kwangyang Steel Company only. In addition to this, the port is developing a container terminal with 10 berths for 50,000GRT container ships, the construction of which is scheduled to be finished in the year 2000. Because of these development, it has been pointed out that the existing waterways are not wide and safe enough for the new large ships to be catered for. This work, therefore, aimed to examine the naviga-tional safety of the waterways of Kwangyang Harbour, and to suggest how to improve the existing water-ways for the large ships to be introduced in the near future. In examining the safety of the existing and newly suggested waterways, waterway design simulation methodology has been applied. From this study, it has been suggested that the No.4 navigational channel has to be dredged to the depth of 22.5 meters and used as an entrance channel only, while the No.3 channel is used as an exit channel. Additionally, a new waterway has been recommended to be established over the Myodo Island for the container ships which will use the new terminal, the width of which has been recommended to be 400 meters with 440 meters from the bend area.
2.
1994.05 서비스 종료(열람 제한)
Several factors can be chosen for evaluating seakeeping performance, such as deck wetness, propeller racing, slamming, rolling, vertical acceleration and vertical bending moment, in consi-deration of the safety of human being, cargo and ship. In fact, there are few developments for an evalua-tion method of seakeepting performance correponding with each ship's characteristics. The purpose of this paper is to develop an quantitative evaluation method of seakeeping performance according to ship types. The scope and the method of this study are as follow. (1) Obtain each response amplitude of ship's motion in waves by Ordinary Strip Method and apply it to short-crested, irregular wave for random process of the factors on seakeeping performance. (2) Define the evaluation index, the dangerousness, the maximum dangerousness and the evaluation diagram. (3) Figure out the different characteristics according to ship types by computer simulation of evaluating seakeeping performance. (4) Adopt vertical acceleration and one of rolling or lateral acceleration as the factors on seakeeping performance by clarifying the correlation of stochastic process. This study developed an evaluation method coincident with each ship's characteristics, and suggested a device for application to actual ship. This method might be useful in developing the practical system of seakeeping performance in accordance with ship types. The ship models for computer simulation are 175m container ship types, 93m tranning ship HANARA as passenger ship type, 259m bulk-carrier type and 164m pure car-carrier type.
3.
1994.05 서비스 종료(열람 제한)
This paper was a part of the risk management in planning a channel. It utilized Korea Marine Training & Research Institutes(KMTRI) which Houses a real-time, full-mission shiphandling simulator to examine the safety of the ship's transit in the planned channel of Asan port. 6 competent Captains participated in this study. The vessel modelled was a 60,000-ton ship. The two variables(factors) examined were environ-mental conditions such as flood-and-ebb current condition and day-and-night condition. The two variables were combined to produce four experimental conditions. To evaluate the safety of the environmental conditions, two categories of performance measures were analyzed. They were vessel's proximity to channel boundary and vessel controalbility. The findings regar-ding the effects of environmental conditions were as follows : - Closest Point of Approach(CPA) to channel boundary was enough for 60,000-ton ship to transit th-rough the channel with 99.999% confidence level. - Closest Point of Approach(CPA) to channel boundary further was under against-current condition than under with-current condition. -Vessel controlability was better under against-current condition than under with-current condition. -Vessel controlability was better under inbound transit than under outbound transit.
4.
1994.05 서비스 종료(열람 제한)
This paper treats the optimization analysis of tactical ship scheduling problems in the world seaborne bulk trade. The authors use the term 'tactial' to describe the ship scheduling problem where the owners should employ skillful tactics as an expedient toward gaining the higher profits per period in short term. Relevent research and related problems on ship scheduling problems are reviewed briefly and a model for the tactical ship scheduling problem formulated as Set Problem is introduced by modifying the previous work of Fisher(1989). The reality and practicability of the model is validated by some ship-ping statistics. Proper solution approaches are outlined in the context of computational tractability in tackling the Mixed Integer Propramming. Some underlying consideration for the computational experiment is also mentioned. The authors conclude the paper with the remarks on the need of user-friendly Decision Support System for ship scheduling under varying decision environment.
5.
1994.05 서비스 종료(열람 제한)
Studies on the ship's automatic navigation & berthing control have been continued by way of solving the ship's mathematical model, but the results of such studies have not reached to our satisfactory level due to its non-linear characteristics at low speed. In this paper, the authors propose a new berthing control system which can evaluate as closely as cap-tain's decision-making by using the FNN(Fuzzy Neural Network) controller which can simulate captain's knowledge. This berthing controller consists of the navigation subsystem FNN controller and the berthing subsystem FNN controller. The learning data are drawn from Ship Handling Simulator (NavSim NMS-90 MK Ⅲ) and represent the ship motion characteristics internally. According to learning procedure, both FNN controllers can tune membership functions and identify fuzzy control rules automatically. The verified results show the FNN controllers effective to incorporate captain's knowledge and experience of berthing.
6.
1994.05 서비스 종료(열람 제한)
Technological and organisational changes in transport system have introduced new dimension into port system development and inter-port competition. The quality of service now required by the customer is costly and not easily provided by small shipping companies and small ports. It has been suggested that in the future container shipping may be concentrated by space-sharing arrangements or actual mergers into the hands of a few mega-operators with the investment potential to provide total logistics networks. In order to compete effectively, high load factors will be essential and port concentration inevitable. A fa-voured few ports will become the load centres and other ports will assume a secondary feeder role. In this study, three questions are raised and attempts are made to answer them : (a) what is the new role of ports today ; (b) why should ports be engaged in this new role ; and (c) how can ports play this new role. In short, a modern port should be a service centre and a logistic platform for international trade and transport-a third generation port. Ports, in particular, have to make every effort to be competitive in the cost and quality of services and to make the port a transport and distribution service centre. For most ports, this is not an option but a must ; an essential requirement for survival in this win or lose situation. The best way to win is to maintain a close contact with port users, listen to them, discuss with them, help them and satisfy them. That is port marketing. Starting from the findings of port marketing, it is es-sential to work out appropriate development plans and marketing targets and to improve port competitive-ness. As an alternative method, a port competitiveness model is suggested, which may help port managers to make appropriate improvements.
7.
1994.05 서비스 종료(열람 제한)
A Contract of marine insurance is a contract whereby the insurer undertakes to indemnity the assurd, in manner and to the extent thereby agreed, against marine losses that is to say, the losses incident to marine adventure. But the matter is that whether the problem of increased risk in insurance law should be understood by matching to nay state under general principle of contract law and whether that we should give any effect is more proper to the original object of the system. For this, it is understood that it is a case to be applied a "clausula rebus sic stantibus" in general today, but it is regarded as the matter that whether "clausula rebus sic stantibs" is charging any position in change of risk and whether we should understood the concept of the risk on the substance of the risk. Accordingly the recognition for the problem like this, study should examine closely into whether any system for the effect of increase in change of risk is more proper and rational system provide the supplementing points through our principle of insurance law and the study by comparing method.by comparing method.
8.
1994.05 서비스 종료(열람 제한)
Sea casualties may happen in ship, cargo and the others concerned with sea transportation. : the shipo-wer, marine insurer and salvage company have been endeavored to compensate salvage award with some rule and regulation such as Marine Insurance Act, York Antwerp Rules and Average adjustment rules. Once sea casualties happened, the salvage contract is established between the owners, marine insurance and salvage company, the contract are divided into so many kinds of them. In this paper, we have an analysis on the character of the salvage contract whether the characteristic contents of them are in benefit to any party or not. In this connection with these positive or negative character of the contract, it is worthwhile to compare the actual salvage expenses contract with no cure no pay contract. LOF 1990 has been revised recently, which is based on no cure no pay, expecially, the special compensation, safety net clause of LOF 1990 could be understood in the view of the prevention of sea pollution and the preservation of sea circumstances in the world. Salvage has the complicated and quality, because the adjustment of almost salvage charges have been treated through the other sea casualties which is accompanied by and mixed with. Besides of the importance of salvage contracts, we are in need to understand that what the diversified character of salvage charges are. Furthermore the owners should carefully select the insured conditions on Hull Insurance according to the type of his company, operating ocean route, loading cargo and etc. In this paper, we would try to analyze the character of the salvage award such as General Average, Sue and Labour Charges and Particular charges. We would like to propose that the uniformed system of the salvage award. Compensation should be built up for the effective and efficient salvage operation and for reducing the claims and conflicts from the concerned parties. To this end, we could expect that the uniformed system for salvage award compensation will come to be the benefit of all owners, insurers, salvage company.
9.
1994.05 서비스 종료(열람 제한)
A wide band design method of an electromagnetic wave absorber using exponentially tapered ferrite, which has very wide band frequency characteristics, is proposed and discussed. The wide band electroma-gnetic wave absorber can be designed by the proposed equivalent material constants method for the re-gions varying spatially in the shape of ferrite. Futhermore, the wide band ferrite electromagnetic wave absorber with taper, which have not only exce-llent reflectivity frequency characteristics but also the band width of 30MHz to 2150 or 2450MHz under the tolerance limits of -20dB reflectivity, were designed.
10.
1994.05 서비스 종료(열람 제한)
Hull roughness due to corrosions of outer hull and had applications on outer hull paints was analyzed theoretically. It's value which was gainable practically, was studied, and estimated power penalty formular correspon-ding to that value were reviewed. Local roughness penalty and roughness texture penalty that paint manahers in ship yard can easily were compared and studied by dotting actual ships in the issued curves. Losses and benifits of hull roughness & the specification choise of A/F paint which managers of ship maintenance were much interested in have been calculated through actual ships. The paper is illustrating that how much the specification choise and managing of A/F paint have effects on fuel consumption of ship in program. It is urgently required that recent developed antifouling paints of new A/F generation should be adopted to new ship building by big shipping companies in view of the environmental protection and the economical maintenance of ships.