• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.34
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• pp.129-137
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• 1995

Recently the recognition of Logistics becomes important to enterprises as a means for improving their competition, but the Korea enterpries falls for far behind in management techniques for analyzing realities and problems in the logistic compare to the advanced countries. In describing a distribution network, we have stated that it is basically a system or a set of locations that ship, receive or store material plus the routes that connect these locations. Using a Dynamic Programming on logistics, we can decrease the inventory level and increase the service level on logistics and the management performance.

• Proceedings of the Korean Society of Computer Information Conference
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• 2017.07a
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• pp.374-375
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• 2017

As the distribution of image contents is activated, users can easily access image contents through various routes and media.In this paper, we propose a new virtual reality (VR) system, which is based on the development of IT technology, in order to prepare for the fourth industrial revolution era.We propose a method of producing educational video contents that combines maximized virtual reality.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.8
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• pp.3551-3567
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• 2016

The Low Earth Orbit satellite network has the unique characteristics of the non-uniform and time-variant traffic load distribution, which often causes severe link congestion and thus results in poor performance for delay-sensitive flows, especially when the network is heavily loaded. To solve this problem, a novel adaptive routing algorithm, referred to as the delay-oriented adaptive routing algorithm (DOAR), is proposed. Different from current reactive schemes, DOAR employs Destination-Sequenced Distance-Vector (DSDV) routing algorithm, which is a proactive scheme. DSDV is extended to a multipath QoS version to generate alternative routes in active with real-time delay metric, which leads to two significant advantages. First, the flows can be timely and accurately detected for route adjustment. Second, it enables fast, flexible, and optimized QoS matching between the alternative routes and adjustment requiring flows and meanwhile avoids delay growth caused by increased hop number and diffused congestion range. In addition, a retrospective route adjustment requesting scheme is designed in DOAR to enlarge the alternative routes set in the severe congestion state in a large area. Simulation result suggests that DOAR performs better than typical adaptive routing algorithms in terms of the throughput and the delay in a variety of traffic intensity.

• Ocean and Polar Research
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• v.23 no.4
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• pp.323-335
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• 2001

Distribution features of foulers attached on 28 ships of 6 main shipping routes (SR) of the Far East Sea Basin were analyzed using various statistical methods. Collections obtained during 1976-1990 in the expeditions by the Institute of Marine Biology were used for the analyses. Samples were taken from the ships during anchorage by SCUBA diving and from dry-docks of Vladivostok ship-repairing yard. In all cases, the distribution patterns of most animals and algal species showed clear contagious patterns. Total biomass of fouling organisms and biomass of attached animals frequently increased along the horizontal direction of ship hulls, from the stem to the sternpost. Animal and algal species were usually located at different sites of the hulls. According to the increasing floating speed, there was, a clear tendency of the displacement in main fouling biomass from the stem to the stem. Any generalizations and deductions concerning the distribution patterns of the foulers from the same SR ships are not always substantiated, but one may see some similarities of the fouler distributions in many cases. Micro-scale turbulence generated by water flow around a ship hull for the distribution of fouling organisms is discussed.

• Progress in Superconductivity and Cryogenics
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• v.7 no.1
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• pp.37-41
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• 2005

This paper describes the construction scheme of new distribution system using HTS(High Temperature Superconducting) power equipments such as cable, transformer and FCL(fault current limiter). At present, one of the most serious problems in distribution power system, especially for metropolitan complex city, is to obtain the ROW for cable line routes, space for downtown substations and satisfy the environmental protection caused by NIMBY phenomena. Unfortunately, it is expected that this situation will get more and more worse. As the HTS technology to apply in power system Is developed, HTS cable utilizing mass-capacity characteristic can be a useful countermeasure to overcome this problem. This paper describes the application methodology of 22.9kV HTS cable with low-voltage, mass-capacity characteristics replacing the 154kV conventional cable. By applying 22.9kV HTS cable, the HTS transformer with higher capacity for the reduction of space and transformer numbers of downtown substation is necessary. Also, if the leakage Impedance of HTS transformer is same as or lower than that of conventional transformer, the fault current of 22.9kV bus will increase because the HTS transformer capacity is larger than that of the conventional transformer. This means the parallel application of HTS-FCL to reduce the fault current in addition to the HTS cable and transformer can be necessary. With the basic construction scheme of new distribution system, this paper describes the future study points to realize this new distribution system using HTS equipments.

• Archives of Pharmacal Research
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• v.18 no.3
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• pp.141-145
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• 1995

Omeprazole, a proton pump inhibitor, was given intravenously (iv), orally (po), intraperitoneally (ip), hepatoportalvenously (pv), and intrarectally (ir) to rats at a dose of 72mg/kg in order to investigate the bioavailability of the drug, The extent of bioavailabilities of omeprazole administered through pv, ip, po, and ir routes were 88.5, 79.4, 40,8, and 38.7%, respectively. Pharmacokinetic analysis in this study and literatures (Regardh et al., 1985 : Watanabe et al., 1994) implied significant dose-dependency in hepatic first-pass metabolism, clearance and distribution, and acidic degradation in gastric fluid. The high bioavailability from the pv administration (88.5%) means that only 11.5% of dose was extracted by the first-pass metabolism through the liver at this dose (72 mg/kg). The low bioavailability from the oral administration (40.8%) in spite of minor hepatic first-pass extraction indicates low transport of the drug from GI lumen to portal vein. From the literature (Pilbrant and Cederberg, 1985), acidic degradation in gastric fluid was considered to be the major cause of the low transport. Thus, enteric coating of oral preparations would enhance the oral bioavailability substantially. The bioavailability of the drug from the rectal route, in which acidic degradation and hepatic first-pass metabolism may not occur, was low (38.7%) but comparable to that from the oral route (40.8 %) indicating poor transport across the rectal membrane. In this case, addition of an appropriate absorption enhancer would improve the bioavailability. Rectal route seems to be an possible alternative to the conventional oral route for omeprazole administration.

• The Journal of Fisheries Business Administration
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• v.31 no.1
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• pp.33-54
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• 2000

This study intends to examine the distribution channel of the most popular ten species caught in Korean coastal and off-shore fisheries with the aid of interviewing fish brokers and cooperative staffs in fish landing markets. This paper finds and emphasizes the following three suggestions, in order to improve the present scheme of fish distribution system. Firstly, annual catch of 10 kinds of fishes is successively decreasing in quantity from 1994 to 1998. Moreover annual catch shows larger variations than fish price and cooperative sales quantity. Except sea eel and sole, cooperative sales accommodates more than 90% of the fish landed, accounting for the small variation in cooperative sales, which invalidates the effectiveness of the free distribution system adopted by the government. Secondly, diversified distribution channels are exposed according to the nature of the fish, the method to harvest, and the quantity caught. Large retailers such as discount stores, super chains and home shopping institutions are actively involving themselves in direct purchase in fish landing markets. Through the analysis of distribution routes, the general distribution channel of fresh fish has been found such as producers longrightarrow fish brokers in landing markets longrightarrow fish brokers in central wholesale markets longrightarrow wholesalers longrightarrow retailers longrightarrow consumers. In order to reduce distribution margin through the analysis of distribution function and distribution margin, this paper presents a new distribution channel such as producers longrightarrow fish brokers in landing markets longrightarrow wholesalers longrightarrow retailers longrightarrow consumers. Thirdly, to improve the fish landing markets, this paper suggests the M&A of uneconomical fish landing markets or renovating toward wholesalers, introduction of processing services and improvement of processing facilities, subsidizing fish brokers in landing markets, revitalization of marketing divisions in cooperatives and improvement in fish auction system.

• Journal of Advanced Navigation Technology
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• v.24 no.5
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• pp.348-357
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• 2020

An important challenge in commercialization of eVTOL PAV is to reduce noise for urban air mobility (UAM) operation. Therefore, in this paper, noise priority routes were created to minimize the number of people affected by noise using aviation environmental design tool (AEDT) software and population distribution data for administrative districts, and noise analyses during operation were performed. Also, it was analyzed how much noise exposure could be reduced compared to the number of people affected by noise in the shortest route. Considering that the eVTOL PAV developers do not provide data, the analysis was conducted using a helicopter model. As a result, it was shown that the noise priority route that minimized the amount of noise exposure was more efficient than other routes.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.1
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• pp.58-66
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• 2005

Floating debris was observed using a training ship, KAYA, of Pukyong National University with cruising speed of about 10-12 knot during July 12~25, 2003. The area sampled was the East Sea enclosed by 3 nations, namely, Korea, Japan and Russia, and was divided into 68 unit segments on survey routes [Fig. 1]. Debris fabrication materials were categorized with 6 items, e.g., man-made or natural wood items, paper and cardboard, nylon rope, styrofoam, vinyl and plastic, floating metal and glass containers. All identified items within $100{\pm}10 m$ wide band were recorded but ignored if beyond this boundary. The results of this study are as follows: 1. The average numbers of debris per unit area, $1km^2$, were found as 16.3 pieces (items) in the sea. 2. The highest densities of numbers, $32.3pieces/km^2$, were discovered in vicinity of the Oki strait of Japan, area of 'NEK' in Fig. 1. 3. Especially, styrofoam item only was composed to 63.6% of all in the sea of 'SD', located in the southern part of Dokdo Island, Korea. The item seems to be derive from the Southern Sea of Korea. 4. Therefore, comparing the distribution of debris numbers (the results of above 2 and 3) with flow patterns of Kuroshio currents, it was shown that their relation was good agree each other. Further more surveys are being conducted and a much wider coverage can be achieved with other countries, then it can be obtained that the East Sea is polluted to some extent, where is the origin of debris, and the finding of floating routes and stationary sea.

• Journal of Fisheries and Marine Sciences Education
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• v.11 no.2
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• pp.203-215
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• 1999

Floating debris was recorded from a training ship, Kaya, of Pukyong National University with about 12 knots speed at July 19~21, 1999 and July 24~26. The sampled area is the Yellow Sea (YS) connected from Cheju Is. of Korea to Qindao harbor of China, divided into 88 unit segments on survey routes. Debris fabrication materials were categorized with 6 items using the following; man-made or natural wood items, paper and cardboard, nylon netting and rope, styrofoams, vinyl and plastics, floating metal and glass containers. All identified items within a $120{\pm}20m$ wide band were recorded but ignored if beyond this boundary. The results of distribution of floating debris in the area are as follows: 1. The greatest quantities of marine debris discovered during the survey were $184pieces\;per\;km^2$ near Qindao harbor. The next polluted areas, Sohuksan islands, positioned in the eastern part of YS were scattered in about $40pieces/km^2$ or so. 2. Among items, woods, paper and cardboard, vinyl and plastics were found out near Qindao Coast of China. On the other hand, there were many styrofoams, nylon netting and rope near the area of Sohuksan islands in the eastern part of YS. 3. The distribution densities of western part of YS near Qindao are varied with largely range in items and quantities but those of the eastern part, near Sohuksan islands were nearly constant. 4. Styrofoams were composed of 63% among all debris in YS, next paper and cardboard 15%, and wood item, vinyl and plastics each 10%. Therefore, marine debris of YS is revealed that distribution characteristics and composition are very different in each area. These phenomena are concluded that they largely depend on the life styles in land and the utilities of the sea. And of items, styrofoams is dominated by the distribution pattern of YS. Furthermore, surveys are continuously being investigated, and from this it is hoped that a much wider coverage can be achieved, perhaps all sites of the YS and contributed to the finding sources, the stationary area and removal method of debris joined the flow patterns.