• Journal of Distribution Science
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• v.16 no.12
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• pp.95-104
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• 2018

Purpose - In order to gain the upper hand in competition between container terminals, efforts to improve container terminal productivity continue. Export containers arrive randomly in the container terminal and are carried in the container terminal yard according to the arrival order. On the other hand, containers are carried out of the container terminal yard in order based on container weight, not in order of arrival. Because the carry-in order and the carry-out order are different, rehandling may occur, which reduces the performance of the container terminals. In order to reduce rehandling number, containers can be moved in advance when they arrive, which is called preprocessing. This paper proposes an effective preprocessing algorithm and analyzes the factors that affect the productivity of the container terminals. It also provides a way to choose the best factors for preprocessing for a variety of situations. Research design, data, and methodology - To analyze the impact of factors affecting the performance of preprocessing algorithms presented in this paper, simulations are performed. The simulations are performed for two types of bays, 12 stacks with 8 tiers, and 8 stacks with 6 tiers. Results - The results of the factor analysis that affects the performance of the preprocessing algorithm were as follows. (1) As the LMF increased, preprocessing number increases and rehandling number decreased. (2) The LML effect was greatest when the LML changed from 0 to 1, and that the effect decreased when it changed above 1. (3) The sum of preprocessing number and rehandling number was then shown to be increased after decrease, as the LMF increased. (4) In the case of NCI, a decrease in NCI showed that the containers would become more grouped and thus the performance was improved. (5) There was a positive effect in the case of EFS. Conclusion - In this paper, preprocessing algorithm was proposed and it was possible to choose the best factors for preprocessing for a variety of situations through simulations. Further research related to this study needs to be carried out in the following topic : a study on the improvement of container performance by connecting the preprocessing with remarshalling.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.24 no.12
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• pp.1670-1675
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• 2020

In this study, to provide the basis for establishing effective network based countermeasures against DRDoS(Distributed Reflection Denial of Service) attacks, we propose a new 'DRDoS attack multi-level detection method' that identifies the network based characteristics of DRDoS and applies probability and statistical techniques. The proposed method removes the limit to which normal traffic can be indiscriminately blocked by unlimited competition in network bandwidth by amplification of reflectors, which is characteristic of DRDoS. This means that by comparing 'Server to Server' and 'Outbound Session Incremental' for it, accurate DRDoS identification and detection is possible and only statistical and probabilistic thresholds are applied to traffic. Thus, network-based information security systems can take advantage of this to completely eliminate DRDoS attack frames. Therefore, it is expected that this study will contribute greatly to identifying and responding to DRDoS attacks.

• Journal of Korea Port Economic Association
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• v.38 no.1
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• pp.1-14
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• 2022

The change in the management environment of the logistics industry in the era of global competition is becoming an era in which customers choose companies. Differentiation from competitors through the provision of products and services suitable for customers As customers' choices change depending on their superiority, companies are constantly striving to receive or retain customers' choices. Ultimately, this competitive structure can be seen as the importance of long-term relationship building. Therefore, in this study, we examined how factors related to transaction characteristics performed by logistics companies for customer satisfaction in the transaction relationship between cargo companies and shippers affect performance and long-term transaction intentions. First, we derived the factors of logistics service, cost, logistics infrastructure, and company competency, which are transaction characteristics factors of a logistics company that must be specifically realized for customer satisfaction in transactions between logistics companies. Second, we analyzed how the transaction characteristics factors of a logistics company affect the company's performance, and finally, how the company's performance factors affect long-term transaction intentions. As a result of empirical analysis, there were no statistically significant results on the relationship between transaction characteristics and performance of logistics companies, which can be attributed to the small size of the logistics companies that were the sample. In other words, logistics companies that do not have sufficient capacity to provide services at low prices have no choice but to engage in constant bleeding competition. It can be seen that it reflects the characteristics of the industry. On the other hand, the relationship between corporate performance factors and long-term transaction intention was found to have a positive relationship. The higher the level of partnership with logistics companies and visible financial performance is, the higher the transaction will be in the future, and the more the transaction volume will be gradually increased. And even if it costs a little more, it can be seen that the intention to continue trading is greatly expressed.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1253-1253
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• 2001

The ability to accurately assess wine quality is important during the wine making process, particularly when allocating batches of wines to styles determined by consumer requirements. Grape payments are often determined by the quality category of the wine that is produced from them. Wine quality, in terms of sensory characteristics, is normally a subjective measure, performed by experienced winemakers, wine competition judges or winetasting panellists. By nature, such assessments can be biased by individual preferences and may be subject to day-to-day variation. Taste and aroma compounds are often present in concentrations below the detection limit of near infrared (NIR) spectroscopy but the more abundant organic compounds offer potential for objective quality grading by this technique. Samples were drawn from one of Australia's major wine shows and from BRL Hardy's post-vintage wine quality allocation tastings. The samples were scanned in transmission mode with a FOSS NIR Systems 6500, over the wavelength range 400-2500 ㎚. Data analysis was performed with the Vision chemometrics package. With samples from the allocation tastings, the best correlations between NIR spectra and tasting data were obtained with dry red wines. These calibrations used loadings in the wavelengths related to anthocyanins, ethanol and possibly tannins. Anthocyanins are a group of compounds responsible for colour in red wines - restricting the wavelengths to those relating to anthocyanins produced calibrations of similar accuracy to those using the full wavelength range. This was particularly marked with Merlot, a variety that tends to have relatively lower anthocyanin levels than Cabernet Sauvignon and Shiraz. For dry white wines, calibrations appeared to be more dependent on ethanol characteristics of the spectrum, implying that quality correlated with fruit maturity. The correlations between NIR spectra and sensory data obtained using the wine show samples were less significant in general. This may be related to the fact that within most classes in the show, the samples may span vintages, glowing areas and winemaking styles, even though they may be made from only one grape variety. For dry red wines, the best calibrations were obtained with a class of Pinot Noir - a variety that tends to be produced in limited areas in Australia and would represent the least matrix variation. Good correlations were obtained with a tawny port class - these wines are sweet, fortified wines, that are aged for long periods in wooden barrels. During the ageing process Maillard browning compounds are formed and the water is lost through the barrels in preference to ethanol, producing “concentrated” darkly coloured wines with high alcohol content. These calibrations indicated heaviest loadings in the water regions of the spectrum, suggesting that “concentration” of the wines was important, whilst the visible and alcohol regions of the spectrum also featured as important factors. NIR calibrations based on sensory scores will always be difficult to obtain due to variation between individual winetasters. Nevertheless, these results warrant further investigation and may provide valuable Insight into the main parameters affecting wine quality.

• KDI Journal of Economic Policy
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• v.12 no.1
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• pp.93-110
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• 1990

The basic purpose behind the Korean government's policy toward the Korean deep sea fishing industry is to limit growth of the industry. Therefore, the regulations on the industry are generally restrictive and interventionist. The policy is intended to maintain high domestic fish prices in order to protect the domestic coastal fishing industry. Some regulations have also been introduced to maintain "industrial order." Each fishing vessel must obtain a government permit for operation. The permit specifies the kind of fish it can catch, the area of sea in which it can operate, and the port at which it can unload its catches. The number of permits government issues each year is based on the estimates of the demand increase calculated by government officials, and the government traditionally has been fairly conservative in its estimation, reflecting its concern for fish price stabilization, which actually implies a gradual increase of the prices. There is also a restriction on importing vessels from abroad. This regulation is intended to protect the domestic shipbuilding industry. However, this regulation has resulted in an unusually high average age of Korean fishing vessels, causing fishing costs to rise. These regulations and the inflexible response of the regulators to changing circumstances have resulted in many problems: i) high domestic fish prices, which are, to some extent deliberately, inflated to three or four times the level of international prices, resulting in huge consumer welfare losses; ii) over-exploitation of coastal fish resources; iii) provision of a hospitable environment for inefficient firms to survive, which is especially evident from the fact that, despite the high fish prices in Korea, most of the firms in the industry do not enjoy high profitability. It also must be pointed out that the actual beneficiaries of the high fish prices are the large operators, who are protected from competition and provide most of the fish for domestic consumption, rather than the low-income fishing households and small coastal operators whom the policy was originally designed to help. This study proposes a set of regulatory reforms and policy changes which could Promote competition and equity within the industry and allow firms to reduce costs and increase productivity. Such changes can make the industry more efficient and internationally competitive. Major proposals are, among others: minimization of bureaucratic discretion in issuing fishing permits and maintaining transparency in the governments' decision-making processes; reduction of the government permit specifications and simplification of the operational categories within the industry; and removal of the restrictions on importing foreign fishing vessels.

• Journal of Korea Port Economic Association
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• v.34 no.1
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• pp.111-132
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• 2018

As China continues to evolve as a major economic power and the Free Trade Agreement (FTA) between the Republic of Korea and China was ratified on June 1, 2015, market volume between the two countries is expected to grow more rapidly. This study aims on improving the efficiency of car-ferry lines. We conducted two surveys- for shippers and forwarders of car-ferry companies, and container liners. The study analyzes the decision factors for delivery companies and their importance for shippers and forwarders of car-ferry companies and container liners. Based on analysis of prior studies on the competition for car-ferry companies and liners, three primary variables are selected-promptness, economics, and safety. The promptness variable consists of shipping time, loading/unloading time, and customs clearing time. The economic variable consists of marine transportation cost from a domestic harbor to China, loading/unloading cost in the harbor, and overland transport cost from the harbor to shippers inland. Finally, the safety variable consists of cargo damage rates, safety facilities, such as lashing and shoring, and punctuality of transportation time. The survey and AHP results show that the promptness, safety, and economics factors are 0.549, 0.309, and 0.142 in the shipper groups of car-ferry companies' category, respectively. It indicates that there is considerable difference in the importance of each factor. In contrast, the factors are 0.350, 0.348, and 0.302 in the forwarders category, which suggests that there is little difference in each factor's importance. As for shippers and forwarders of liners, the importance of each factor is found to be in the following order: economics, safety, and promptness.

• Journal of the Korean Institute of Navigation
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• v.13 no.1
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• pp.21-53
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• 1989

In the past twenty years, there has been a rapid increase in the volume of traffic in Korea due to the Korean great growth of the Korean economy. Since transformation provides an infrastructure vital to economic growth, it becomes more and more an integral part of the Korea economy. The importance of coastal shipping stands out in particular, not only because of the expansion limit on the road network, but also because of saturation in the capacity of rail transportation. In spite of this increase and its importance, coastal shipping is falling behind partly because it is givenless emphasis than ocean-going shipping and other inland transportation systems and partly because of overcompetition due to excessive ship tonnage. Therefore, estimating and planning optimum ship tonnage is the first take to develop Korean coastal shipping. This paper aims to estimate the optimum coastal ship tonnage by computer simulation and finally to draw up plans for the ship tonnage balance according to supply and demand. The estimation of the optimum ship tonnage is peformed by the method of Origin -Destimation and time series analysis. The result are as follows : (1) The optimum ship tonnage in 1987 was 358, 680 DWT, which is 54% of the current ship tonnage (481 ships, 662, 664DWT) that is equal to the optimum ship tonnage in 1998. this overcapacity result is in excessive competition and financial difficulties in Korea coastal shipping. (2) The excessive ship tonnage can be broken down into ship types as follows : oil carrier 250, 926 DWT(350%), cement carrier 9, 977 DWT(119%), iron material/machinery carrier 25, 665 DWT(117%), general cargo carrier 17, 416DWT(112%). (3) the current total ship crew of 5, 079 is more than the verified optimally efficient figure of 3, 808 by 1271. (4) From the viewpoint of management strategy, it is necessary that excessive ship tonnage be reduced and uneconomic outdated vessels be broken up. And its found that the diversion into economically efficient fleets is urgently required in order to meet increasing annual rate in the amounts of cargo(23, 877DWT). (5) The plans for the ship tonnage balance according to supply and demand are as follows 1) The establishment of a legislative system for the arrangement of ship tonnage. This would involve; (a) The announcement of an optimum tonnage which guides the licensing of cargo vessels and ship tonnage supply. (b) The establishment of an organization that substantially arrangement tonnage in Korea coastal shipping. 2) The announcement of an optimum ship tonnage both per year and short-term that guides current tonnage supply plans. 3) The settlement of elastic tariffs resulting in the protect6ion of coastal shipping's share from other tonnage supply plans. 4) The settlement of elastic tariffs resulting in the protection of coastal shipping's share from other transportation systems. 4) Restriction of ocean-going vessels from participating in coastal shipping routes. 5) Business rationalization of coastal shipping company which reduces uneconomic outdated vessels and boosts the national economy. If we are to achieve these ends, the followings are prerequisites; I) Because many non-licensed vessels are actually operating and threatening the safe voyage of the others in Korea coastal routes, it is necessary that those ind of vessels be controlled and punished by the authorities. II) The supply of ship tonnage in Korean coastal routes should be predently monitored because most of the coastal vessels are to small to be diverted into ocean-going routes in case of excessive supply. III) Every ship type which is engaged in coastal shipping should be specialized according to the characteristics of its routes as soon possible.

• Journal of the Korean Institute of Navigation
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• v.4 no.2
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• pp.45-79
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• 1980

The aim of this paper is to analyze the mechanics of price formation in the tramp shipping. For the purpose of this study, the main characteristics of tramp freight rates and the market is examined, and a brief examination of the nature ofthe costs of operation is given which are essential for the understanding of the functioning of shipping firms as well as for the understanding of developments in the tramp freight market. The demand and supply relationships in the market is also analysed in detail. Tramp shipping is an industry that has a market which functions under conditions that are not dissimilar to the theoretical model of perfect competition. However, it does notmean that tramp shipping market is a perfectly competitive market. It is apparent that this realworld competitive system has its imperfections, which means that the market for tramp shipping is near to being a perfectly competitive market on an internaitonal scale and it is freight are therefore subjext to the laws of supply and demand. In theory, the minimum freight rate in the short term is that at which the lowest cost vessels will lay-up in preference to operating, and is equal to the variable costs minus lay-up costs; and this would imply that in all times except those of full employment for ships there is a tendency for newer low-cost, and, probably, faster vessels to be driving the older high-cost vessels in the breaker's yards. In this case, shipowners may be reluctant to lay-up their ships becasue of obligations to crews, or because they would lose credibility with shippers or financiers, or simply because of lost prestige. Mainly, however, the decision is made on strictly economic grounds. When, for example, the total operating costs minus the likely freight earnings are greater than the cost of taking the ship out of service, maintaining it, and recommissioning it, then a ship may be considered for laying-up; shipowners will, in other words, run the ships at freight earnings below operating costs by as much as the cost of laying them up. As described above, the freight rates fixed on the tramp shipping market are subject to the laws of supply and demand. In other words, the basic properties of supply and demand are of significance so far as price or rate fluctuations in the tramp freight market are concerned. In connection with the same of the demand for tramp shipping services, the following points should be brone in mind: (a) That the magnitude of demand for sea transport of dry cargoes in general and for tramp shipping services in particular is increasing in the long run. (b) That owning to external factors, the demand for tramp shipping services is capable of varying sharphy at a given going of time. (c) The demad for the industry's services tends to be price inelastic in the short run. On the other hand the demand for the services offered by the individual shipping firm tends as a rule to be infinitely price elastic. In the meantime, the properties of the supply of the tramp shipping facilities are that it cannot expand or contract in the short run. Also, that in the long run there is a time-lag between entrepreneurs' decision to expand their fleets and the actual time of delivery of the new vessels. Thus, supply is inelastic and not capable of responding to demand and price changes at a given period of time. In conclusion, it can be safely stated that short-run changes in freight rates are a direct result of variations in the magnitude of demand for tramp shipping facilities, whilest the average level of freight rates is brought down to relatively low levels over prolonged periods of time.