• Journal of the Korean Institute of Navigation
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• v.25 no.1
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• pp.77-91
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• 2001

According to the many ancient literatures, it is said to be that Merchant Prince, Chang Pogo in unification Silla had traded with not only China, Japan but also Arab-Islam Countries, but unfortunately there is no definite records about this. Therefore in this study the writer would like to presume the sea routes of Merchant Prince, Chang Pogo in a unification Silla. For the purpose of this study the writer would like to study the reference books and materials regarding to the sea routes of prehistoric age and ancient three countries of Kingdoms and unification Silla. Especially the writer consider “The Work of Routes and Kingdoms” of Ibn Khurdarhbih regarding to the ancient sea routes of Korea, China, Arab-Islam Countries, and also the writer consider the ancient sea routes of Tang Dynasty in China and Ryukyu Kingdom in Japan. About this methodology of this study, the writer believe that the sea routes of today is the results of ancient sea routes, and this ancient sea routes could not be changed forever except special circumstance. According in this study the writer would like to persume the sea routes of Merchant Prince, Chang Pogo using like this methodologies. This presumption of the writer is originated on the basis of The Work of Routes and Kingdoms written by ancient Arabian Geographer, Ibn Khurdadhbih in the early years of 9th century. The Work of Routes and Kingdoms is geography, and the principal contents of this geography are the activities of Arab-Islam merchants and Chinese Merchants between Arab-Islam countries and China from 9th century to 11th century by ancient sea routes. But surprisingly in this geography, Silla was marked, and another ancient Arabian geogrpher, Al-Biruni marked Silla on his map, Qanun Al-mas'udi in the 9th century, and also another ancient Arabian geographer, Al-Idrisi marked Silla on his map in the 11th century. Especially Al-Biruni expressed the longitude and latitude of Silla on his map, he expressed Silla as following. “at the extreme end of China toward the East and few people travelled to it by sea”. Therefore the writer would like to presume that Arab-Islam merchants had traded with unification Silla in the 9th century, and also Merchant Prince, Chang Pogo had traded with not only China, Japan but also Arab-Islam Countries using above ancient sea routes in the 9th century.

• 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.

• Strategy21
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• s.33
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• pp.113-147
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• 2014

While China's military rise is an issue of growing importance to regional security, it is worthwhile to note that it is not China's military modernization per se, but its capacity to project and sustain power along and beyond its borders--in particular, the possibility to resolve forcefully its outstanding maritime disputes and various contingencies. This essay argues that China's "anti-access capability"--a U.S.-coined term originally developed for a Taiwan contingency--is equally applicable to other major regional cases such as the Spratly disputes and a North Korean contingency. Furthermore, notwithstanding China's continuos efforts to develop and deploy various types and classes of weapons/platforms, it is the Russian systems and technologies that are most capable and thus likely assigned to the highest mission-critical areas. In assessing China's current and likely future military capability as well as their implications for the region, it is necessary to take note of the following: • There exists asymmetry of military capability between China and its weaker neighbors. While the PLAN is weak in several important aspects, for instance, many of its neighbors' navies are weaker still. • Some have argued that China's foreign policy behavior apparently became more "assertive" in 2009-2013, but it is wiser to keep in mind that China has almost always been assertive and aggressive when it comes to what China defines as "sovereignty and territorial issues" as well as its newest "core interests." • On the South China Sea disputes it is the function of U.S. presence in the theater--in the form of overseas bases and the freedom of navigation--and the PLA's own limitations to project and sustain power for an extended period of time that have largely prevented armed. • While Taiwan remains the idee fixe of China's diplomacy and military, it is and will be a tough nut to crack. China's recent creeping attempts for economic integration with Taiwan should be seen in this context. • China and Japan, the two regional heavyweights and traditional rivals, will likely have a bilateral relationship that is replete with difficulties and tension. China's unilateral announcement of its ADIZ in November 2013 as well as the occasional yet persistent disputes with Japan over the Senkaku/Diaoyudao/Diaoyutai islands are only the latest manifestation of this deeper and difficult relationship. • For Korean security it is imperative to take into account the geostrategic and historical factors. On top of the existing military threats from North Korea, the ROK should be able to employ a) hedging strategy, b) "limited defense sufficiency" strategy, and c) rock-solid relations with the United States.

• Journal of the Korea Society of Computer and Information
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• v.24 no.12
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• pp.25-33
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• 2019

This paper presents a novel evolutionary framework for optimizing a bio-inspired fully dynamic neurocontroller for the maneuverable flapping flight of a simulated bird-sized ornithopter robot which takes advantage of the morphological computation and mechansensory feedback to improve flight stability. In order to cope with the difficulty of generating robust flapping flight and its maneuver, the wing of robot is modelled as a series of sub-plates joined by passive torsional springs, which implements the simplified version of feathers attached to the forearm skeleton. The neural controller is designed to have a bilaterally symmetric structure which consists of two fully connected neural network modules receiving mirrored sensory inputs from a series of flight navigation sensors as well as feather mechanosensors to let them participate in pattern generation. The synergy of wing compliance and its sensory reflexes gives a possibility that the robot can feel and exploit aerodynamic forces on its wings to potentially contribute to the agility and stability during flight. The evolved robot exhibited target-following flight maneuver using asymmetric wing movements as well as its tail, showing robustness to external aerodynamic disturbances.

• Proceedings of the Ginseng society Conference
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• 1998.06a
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• pp.1-11
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• 1998

Ameliorating mechanisms of red ginseng on learning deficits were investigated in the following 3 experiments; its effects on 1) place learning deficits in aged rats and in young rats with selective hippocampal lesions (behavioral study), 2) long-term potentiation in the hippocampal formation (neuro- physiological study), and 3) ChAT (choline acetyl transferase) activity in various brain regions of aged rats (pharmacological study). In the behavioral study, first, performance in the place learning tasks were compared among 3 groups of young and aged rats; control young intact rats (10-12 week old) treated with water, aged rats (28-32 month old) treated with water, and aged rats (28-32 month old) treated with red ginseng (100 mghglday) suspended in water. Second, performance in the place learning tasks was compared among 3 groups of young rats; control intact rats treated with water, rats with bilateral hippocampal lesions treated with water, and rats with bilateral hippocampal lesions treated with red ginseng (100 mg/kg/day). Each rat in these 2 behavioral experiments was tested with the 3 types of the place learning tasks in a circular open field using intracranial self-stimulation (ICSS) as reward. The ICSS reward was delivered if the rat (1) moved distance of 100-160 cm (DMT): (2) entered an experiment-determined reward place within the open field, and this place was randomly varied in sequential trials (RRPST); or (3) entered 2 specific places, and did a shuttle behavior between the 2 places (PLT). Performance of the aged rats in the ginseng group was not significantly different from that of control young rats in ICSS (current intensity, bar press rates), DMT and RRPST. However, treatment with red ginseng significantly ameliorated place-navigation learning deficits in aged rats in the PLT. Similarly, red ginseng ameliorated learning and memory deficits in young rats with hippocampal lesions in the same tasks. In the neurophysiological study using young rats, perfusion of hippocampal slices with non-sapon in fraction of red ginseng significantly enhanced magnitudes of the long-term potentiation (LfP) in the CA3 subfield. In the pharmacological study, treatment with red ginseng did not affect ChAT activity in aged rat brain including the hippocampal formation. These results strongly suggest that red ginseng ameliorates learning and memory deficits in aged rats through actions on the CA3 subfield of the hippocampal formation, which were independent of the presynaptic components of the cholinergic system

• Journal of Korean Port Research
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• v.13 no.2
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• pp.333-350
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• 1999

Today freeway is thought to be a very important transportation facility carrying tremendous traffic flow as the main corridor within the area of between the areas. However freeway is experiencing severe congestion and accidents by increased entrance ramp flow especially at peak time period. Ramp meters on the freeway entrance ramps that supply traffic to the freeway in a measured or appropriately regulated amount are needed for alleviating freeway congestion. Because ramp meters can be operated to discharge traffic at a measured or regulated rate thus maintaining more uniform speed on the mainline section maximizing the throughput to the freeway within the capacity of a downstream bottleneck and reducing the congestion related accidents. Thus the objectives in this study were to analyze the traffic characteristics on the freeway I-94 with ramp metering system before/after ITS technology in Detroit (Michigan) area compare shifts of the traffic characteristics on the freeway I-94 before/after ITS technology and finally suggest a better ramp metering strategy for the freeway system The following results were obtained: i)Flow occupancies and speeds on the mainline merge section of freeway were shown to be a big difference depending on the peak periods areas and directions based on the distribution of traffic flow characteristics on the freeway. ii)Reduced speed was shown to be more than 5 mph and ramp flow was also shown to be more than 240 vph at peak periods if there was the ramp metering system constructed on the freeway. iii)Ramp metering system was shown to be optimally operated on the freeway if ramp flow could be maximized within the range of over 900 vph and reduced occupancy could be also maximized by no more than 2 percent at peak periods. iv)The average flows on the freeway after the ITS technology were shown to be a decrease of over 20% depending on the peak periods areas and directions when compared with those flow on the freeway before the ITS technology. over 20% depending on the peak periods areas and directions when compared with those speeds on the freeway before the ITS technology. vi)The average metering rates on the freeway after the ITS technology were shown to be an increase of over 10% depending on the peak periods areas and directions when compared with those metering rates on the freeway before the ITS technology.

• Journal of Korean Port Research
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• v.10 no.2
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• pp.17-29
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• 1996

It is required to consider pricing and non-pricing factors and external economy in order to achieve the objects of physical distribution system in a port. Recently, among the three factors, much attention has been paid to non-pricing factor in the system. Although physical distribution service in a port(PDSP)has been frequently mentioned in documents and literature related to port and shipping studies, few study on it has not been systematically and scientifically made due to the following problems; $\circ$ there are not proper criteria to evaluate level and quality of PDSP and as a result it is difficult to set up a unified standard for doing so. $\circ$ algorithms to evaluate problems with complex and ambiguous attributes and multiple levels in PDSP are not available. This thesis aims to establish a paradigm to evaluate PDSP and to abvance existing decision making methods to deal with complex and ambiguous problems in PDSP. To tackle the first purpose, extensive and thorough literature survey was carried out on general physical distribution service, which is a corner stone to handle PDSp. In addition, through interviews and questionnaire to the expert, it have extracted 82 factors of physical distribution service in a port. They have been classified into 6 groups by KJ method and each group defined by the expert's advice as follows; a. Potentiality b. Exactness c. safety d. Speediness e. Convenience f. Linkage Prior to the service evaluation, many kinds of its attributes must be identified on the basis of rational decision owing to complexity and ambiguity inherent in PDSP. An analytical hierarchy process (AHP) is a method to evaluate them but it is not applicable to PDSP that have property of non-additivity and overlapped attributes. Therefore, probablility measure can not be used to evaluate PDSP but fuzzy measure is required. Hierarchical fuzzy integral method, which is merged AHP with fuzzy measure, is also not effective method to evaluate attributes because it has vary complicated way to calculate fuzzy measure identification coefficient of attributes. A new evaluation algorithm has been introduced to solve problems with multi-attribute and multi-level hierarchy, which is called hierarchy fuzzy process(HFP).Analysis on ambiguous aspects of PDSP under study which is not easy to be defined is prerequisite to evaluate it. HFP is different from algorithm existed in that it clarified the relationship between fuzzy measure and probability measure adopted in AHP and that it directly calculates the family of fuzzy measure from overlapping coefficient and probability measure to treat and evaluate ambiguous and complex aspects of PDSP. A new evaluation algorithm HFP was applied to evaluate level of physical distribution service in the biggest twenty container port in the world. The ranks of the ports are as follows; 1. Rotterdam Port, 2. Hamburg Port, 3. Singapore Port, 4. Seattle Port, 5. Yokohama Port, 6. Long beach Port, 7. Oakland Port, 8. Tokyo Port, 9. Hongkong Port, 10. Kobe Port, 11. Los Angeles Port, 12. New york Port, 13. Antwerp Port, 14. Felixstowe Port, 15. Bremerhaven Port, 16. Le'Havre Port, 17. Kaoshung Port, 18. Killung Port, 19. Bangkok Port, 20. Pusan Port

• Journal of Ocean Engineering and Technology
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• v.30 no.5
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• pp.389-399
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• 2016

This paper presents the explorations of hydrothermal vents located in the Marina Arc and Back Arc Basin using the deep-sea ROV Hemire. These explorations were conducted by KRISO and KIOST to demonstrate the capability of Hemire in various applications for deep-sea scientific research. The missions included the following: (1) to search the reported vents, (2) conduct visual inspections, (3) deploy/recover a sediment trap and bait traps, (4) sample sediment/water/rock, (5) measure the magnetic field at the vent site, and (6) acquire a detailed map using multi-beam sonar near the bottom. We installed three HD cameras for precise visual inspection, a high-temperature thermometer, a three-component magnetometer, and a multi-beam sonar to acquire details of the bottom contour or identify vents in the survey area. The explorations were performed in an expedition from March 23 to April 5, 2016, and the missions were successfully completed. This paper discusses the operational process, navigation, and control of Hemire, as well as the exploration results.

• Acta Via Serica
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• v.3 no.2
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• pp.49-72
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• 2018

The extensive maritime trade network between the Harappan and Mesopotamian civilizations as early as the $3^{rd}$ millennium BCE is a testimony to the long maritime trade history of India. From the dawn of the historical epoch, the maritime trade network of India expanded extensively. The findings of a large number of coins, pottery, amphorae and other materials from Italy and various other European countries, west Asia, China, Korea, Africa, the Arabian Peninsula, Sri Lanka, Southeast Asia and Far-East countries in India, particularly in the coastal regions, are a testimony to the dynamic maritime trade of India with other countries in the early period. Similarly, pottery, sculptures, inscriptions and other materials of Indian origin are also found in those countries. The depiction of different types of ships on the coins, paintings, sculptures, seals and sealing, exhibit the variety of vessels used for navigation and other purposes in the early period. The over 7500 km-long coastline of India is well known for its seaports located at river mouths or outlets to the sea. The Periplus Maris Erythraei, Ptolemy, and Indian literary sources mention many seaports on the western coast of India. Interestingly, archaeological investigations in many of these port towns have yielded material evidence exhibiting their dominant role in transoceanic trade and commerce with many countries in the early period. This paper discusses in detail all the major ancient seaports on the western coast of India and their maritime trade activities. At the outset, the paper briefly deals with the Harappan's maritime network, their seaports and the type of ships of that period. Following this, the maritime trade network of India during the historical period with various countries in the east and west, the traces of Indian influence and materials abroad and foreign materials found in India, the products exported from India, the trade winds and navigational devices and the depiction of ships on the coins, paintings, and sculptures of the period are discussed in detail. After briefly highlighting the coastline of India and its favourable nature for safe anchorage of ships and the strategic position of the seaports of western India, an extensive account of the major ancient seaports of western India like Barygaza, Ashtacampra, Gundigar, Kammoni, Khambhat, Bardaxema, Suparaka, Calliena, Semylla, Sanjan, Naura, Tyndis, Muziris, Nelcynda and other seaports, and their maritime trade activities are given based on archaeological excavations and explorations, literature, epigraphy, foreign accounts, and numismatic evidence.

• Journal of the Korean Society of Marine Environment & Safety
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• v.23 no.7
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• pp.847-857
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• 2017

The present situations of the education and training systems for the response to marine HNS spill incidents in domestic and foreign countries were reviewed and the plans to improve domestic system were suggested on the basis of the comparison between domestic and foreign education systems. There were almost no private education and training institutions in Korea, and they have not been activated, compared with those of foreign countries such as USA, Canada, Australia and UK. The domestic marine HNS-related education has been implemented uniformly under Korean government initiative. In addition, there were differences in the targets and duration of the education offered by Korea Coast Guard Academy (KCGA) and Marine Environment Research & Training Institute (MERTI) in Korea. Domestic HNS-related curriculum was relatively simple, compared with the curricula of foreign countries, and has not accepted two levels (operational level and manager level) required in HNS model courses of International Maritime Organization (IMO). The domestic education and training period was short relatively to those of foreign countries. The following suggestions were made to improve the education and training system for the response to domestic marine chemical incidents. In the short term, an HNS education and training management consultation body (tentative name) should be established, with both KCGA and MERTI participating jointly while maintaining the current system of the two institutions (KCGA and MERTI) simultaneously. In the more distant and long term, the HNS-related departments of KCGA and MERTI should be incorporated into a National Marine HNS Response Academy (tentative name) as unified system to enable international competitiveness.