• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2012.06a
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• pp.52-54
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• 2012

Saigon-Vungtau fairway is the main and the most important fairway of the major economic areas: Ho Chi Minh City, Dong Nai Province and Ba Ria-Vung Tau Province in Vietnam. In last 5 years, 80% of accidents happened on the fairway were caused by collision and contact/impact. This presentation study on marine traffic investigation in the adjacent of the fairway to find out problems related to marine traffic for improving Marine Traffic Safety Management in this area.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.23 no.9A
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• pp.2249-2257
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• 1998

In this paper, we propose the enhanced priority control algorithm that adaptively controls the cell service ratio according to the relative cell occupancy ratio of buffer. The asynchronous transfer mode (ATM) provides the means to support various multimedia services in broadband networks. To support multimedia services, various data traffics of different priorities should be controlled effectively. And also it needs congestion control functions required in the netowrk to carry out the control operation. To accomplish this in a flexible and effective manner, priority classes for the different services ar ecommonly used. The proposed enhanced priority control mechanism have two service calsses of the delay sensitive class and the loss sensitive class. The simulation results show that te proposed control mechanism improves the QoS, the charateristics of cell loss probability and mean cell delay time, by selecting propeor relativ ecell occupancy ratio of buffer and the average arrival rate.

• Korean Journal of Veterinary Service
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• v.16 no.1
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• pp.57-64
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• 1993

This survey was performed to report rare outbreak of liver cirrhosis in Korean native goat (KNG) which was died of Yangpyeong's goat farm on Feb. 1992. The examination for the KNG was carried out by clinical signs, necropsy and various lab-oratory test including parasitic, bacterial and histological test. The KNG looked jaundice, ascite, hemorrhage of lumen, abomasum and intestine, and brownish smooth cirrhotic liver at necropsy. Histological examination for liver revealed considerable proliferation of connective tissue and piecemeal necrosis which was caused by chronic active inflammation in interlobules and intralobules. There were atrophic micro and macro nodules which were sur-rounded by connective tissue. The lobular structure lack almost all central vein. The portal areas appearred proliferation of bile ducts, blood vessels and connective tissues. These connective tissue infiltrated heavily with plasma cells, Iymphocytes and histocytes. Histological examination for brain proved to be hepatic encephalopathy by virture of congestion and edema in cerebral medullary. From these results were demonstrated miked nodular, active, postnecrotic liver cirrhosis.

• Journal of KIISE:Information Networking
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• v.31 no.6
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• pp.595-607
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• 2004

Networks often evolve to provide a host with multiple access points to the Internet. In this paper, we propose a transport layer load distribution mechanism utilizing the multiple network interfaces simultaneously. We specifically propose an extension of Stream Control Transmission Protoco1 (SCTP) to have load sharing over multiple network interfaces. We named the particular service provided by the Proposed load sharing mechanism to be LS (Load Sharing) mode service. LS mode service is based on the following four key elements: (i) the separation of flow control and congestion control, (ii) congestion window based striping, (iii) redundant packet retransmission for fast packet loss recovery, (iv) a novel mechanism to keep track of the receiver window size with the SACKS even if they arrive out-of-order. Through simulations, it is shown that the proposed LS mode service can aggregate the bandwidth of multiple paths almost ideally despite of the disparity in their bandwidth. When a path with a delay of 100% greater is utilized as the second path, the throughput is enhanced about 20%.

• MALSORI
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• no.39
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• pp.43-51
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• 2000

The aim of this paper is to present a phonetically oriented keyboard array for the International Korean Phonetic Alphabet (IKPA). IKPA is a phonetic alphabet devised on the basis of Hangout (Korean alphabet) (Lee, 1999). Every computer has a keyboard as its input device and the English keyboard array is hewn as 'QWERTY' system, which represents the first six letters of the second line of the keyboard. This array is a traditional one devised to protect the congestion of the keys of the mechanical typewriter. To improve the anay of the keyboard, another system named 'Dvorak' has been devised. Likewise, a serious attempt has been made by the authors to work out an efficient keyboard for IKPA representing the manner of vowel and consonant classification. In the phonetic keyboard, the consonant symbols are arranged in the left hand side according to the Place and mauler of the articulation and the vowel symbols in the right hand side according to the vowel quadrilateral.

• Proceedings of the Korean Geotechical Society Conference
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• 1993.03a
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• pp.41-48
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• 1993

The 2nd phase of Seoul Subway, Lines 5,6,7 and 8, is in progress. To reduce the surface traffic congestion during construction the greater part of the system has been engineered by bored tunnelling. The current tunnelling methodology is based on the New Austrian Tunnelling Method. Serveral collapses have been reported to date. Most of the collapses took place in the area forwed with soft ground. The modes and causes of the collapses were progressive failures in the unsupported surface and sliding failures due to the unfavourable joint direction. The major causes turned out to be the weakness of ground and the sudden influx of ground water from the surface. Some measures to prevent the failures are also presented. To ensure the safe tunnelling ghrough the soft ground the unsupported excavation area has to be minimized and closed as early as possible. Additional support measures such as supporting core, sealing shotcrete, forepoling, spread footing, face rock bolting and grouting should be employed as well depend on ground conditions.

• IE interfaces
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• v.11 no.1
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• pp.75-84
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• 1998

The important issue for intra-city vehicle scheduling is to measure and store actual vehicle travel speeds between customer locations. Travel speeds(and times) in nearly all metropolitan areas change drastically during the day because of congestion in certain parts of the city road network. We propose three models for estimating departure time-dependent travel speeds between locations that relieve much burden for the data collection and computer storage requirements. Two of the three models use a least squares method and the rest one employs a neural network trained with the back-propagation rule. On a real-world study using the travel speed data collected in Seoul, we found out that the neural network model is more accurate than the other two models.

• Information and Communications Magazine
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• v.10 no.8
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• pp.77-87
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• 1993

There has been increasing attention paid to the influence of fascimile type of technologies on transportation costs. This attention is noticeable in large business companies, as fascimile become widely available in Korea. The importance of the fascimile usage is that it might effectively substitute for transportation, thereby reducing transportation costs. This paper presents an analysis of cost saving resulting from fascimile usage for substitutable trips. Data were collected from business companies on various aspects of the fascimile usage patterns, with particular emphasis on usage behavior substitutable for trips. Although by no means comprehensive, the analysis revealed that significant benefits can be derived from the usage of fascimile for substitutable trips in business settings. The results of benefit estimation show that net benefits turn out to be 7,608 won and 5,055 won per one usage for large and small companies respectively. If traffic congestion were to be considered, total social benefits would be higher.

• Bulletin of the Korean Chemical Society
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• v.13 no.1
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• pp.59-64
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• 1992

The contrasting behaviour of meso-and d,l-$D_3$-trishomocubylidene-$D_3$-trishomocubane (1 and 2) in the electrophilic addition reaction, the former giving rearranged spiro compound (1a and 1b) and the latter giving 1,2-adduct (2a and 2b), has been explained as arising from the secondary steric effects based on computational evidence. As the degree of out-of-plane deformation of the olefinic carbon atoms increases with reaction progress, the resulting internal congestion in the region behind the double bond becomes unbearably large in meso-1. The absence of symmetry plane across the double bond of d,l-2 helps for the closing fragments to adjust themselves.

• Structural Engineering and Mechanics
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• v.74 no.2
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• pp.243-254
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• 2020

Devastating RC structural failures in the past have identified that the behavior of beam-column joints is more critical and significantly governs the global structural response under seismic loading. The congestion of reinforcement at the beam-column joints with other constructional difficulties has escalated the attention required for strengthening RC beam-column joints. In this context, numerous studies have been carried out in the past, which mainly focused on jacketing the joints with different materials. However, there is no comparative study of different approaches used to strengthen RC beam-column joints, from efficiency and cost perspective. This paper presents a detailed investigation carried out to study the various strengthening schemes of exterior RC beam-column joints, viz., steel fiber reinforcement, carbon fiber reinforced polymer (CFRP) strengthening, steel haunch strengthening, and confining joint reinforcement. The effectiveness of each scheme was evaluated experimentally. These specimens were tested under horizontal loading that produced opening moments on the joints and their behavior was studied with emphasis on strength, displacement ductility, stiffness, and failure mechanism. Special attention was given to the study of crack-width.