• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.2
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• pp.1-7
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• 2003

Mode superposition method(MSM) is the most commonly used for solving linear response problems of structural dynamics. The major advantage of MSM is that usually a small number of lower mode is sufficient to analysis the response. However, the convergence is slow and many modes would be needed to give an accurate MSM in large structure with many degrees of freedom. The inaccuracies of MSM are caused by mode truncation in the solution. These demerits can be overcome by use of the mode acceleration method(MAM). Example analyses are carried out in simple beam subjected to harmonic loadings and compared the convergence of the joint displacements by the two methods. For relatively low frequency loadings, a good results was obtained by the lowest one mode in MAM, so the method is more economic in numerical analysis on an accurate solution.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.4B
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• pp.178-185
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• 2005

NEMO basic support is a solution that provides network mobility in the Internet topology. Yet, when multiple mobile networks are nested, this basic solution suffers ken pinball-routing and a severe routing overhead. Therefore, several solutions for route optimization in a nested mobile network have already been suggested by the IETF NEMO WG. However, the current paper proposes Regional Information-based Route Optimization (RIRO) in which mobile routers maintain a Nested Router List (NRL) to obtain next-hop information, and packets are transmitted with a new routing header called an RIRO Routing Header (RIRO-RH). We showed that RIRO had the minimum packet overhead that remained constant, irrespective of how deep the mobile network was nested, in comparison with two earlier proposed schemes - Reverse Routing Header (RRH) and Bi-directional tunnel between HA and Top-Level mobile router (BHT).

• Journal of KIISE:Information Networking
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• v.33 no.6
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• pp.451-460
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• 2006

In HMIPv6, the nested mobile network because of the mobility of node and router can be constituted. Many subnets exist and many mobile router(MR)s and mobile node(MN)s activate in the nested mobile network. If the nested depth is deeper, the number of mobile router that packet goes through, increases and data transmission delay owing to this might be larger. This paper proposes EPA algorithm which finds out the path from Mobility Anchor Point(MAP) to a destination mobile node using the binding cache information of MAP and processes the path information by adding it to packet header. If we apply EAP algorithm, the quantity of unnecessary packet within MAP domain can be decreased. Also, the transmission delay can be decreased in a intermediate mobile router because it supports packet re-transmission just by simple packet substitution.

• Journal of KIISE:Information Networking
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• v.36 no.4
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• pp.309-321
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• 2009

Nowadays, requests of connecting to the Internet while moving are increasing more and more, and various technologies have been developed for satisfying those requests. The IETF nemo WG standardized "Network Mobility Basic Support Protocol" for supporting mobile network through extending existing MIPv6 protocol for supporting host mobility. But, mobile networks can be nested while they are changing their location. And if they are multi -level nested, that causes some problems because of protocol characteristic. In this paper, we try to solve the problem that is complicated routing path caused by multi-level nesting of mobile networks with our limited prefix delegation method. We give a little modification to the standard protocol and add some functions to mobile router. With results from analysis, we could say that our method has better performance than other proposed methods.

• Korean Journal of Environment and Ecology
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• v.37 no.6
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• pp.418-428
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• 2023

This study was conducted to clarify the daily activity patterns overlap between hikers and mammals from 2015 to 2019 in the Baekdudaegan protected area. To investigate relationship behaviors between hikers and mammals, we set the camera traps on the ridge of the Baekdudaegan protected area. Daily activity patterns of yellow-throated marten (Martes flavigula) and Siberian chipmunk (Eutamias sibiricus) were highly overlapped with hiker total study periods. Moreover, daily activity patterns of Siberian roe deer (Caperohus pygargus) and water deer (Hydropotes inermis) were highly overlapped with hikers only in spring. In winter, daily activity patterns of wild boar (Sus scrofa) were overlapped with hikers. However, leopard cat (Prionailurus bengalensis), raccoon dog (Nyctereutes procyonoides), and Eurasian badger (Meles leucurus) did not significantly overlap with hikers during the study periods. The daily activity patterns of 8 mammals differed by species-specific behavior and temporal characteristics. Overlap of daily activity patterns between mammals and hikers were differed in each season. Differences in daily activity pattern overlap between mammals and humans may lead to differences in human impact on mammal populations. Information on the interaction between hikers and mammals on species-specific and temporal-specific behavior could be basic ecological data for management and conservation of mammal populations and their habitats.

• Journal of Institute of Convergence Technology
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• v.11 no.1
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• pp.39-42
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• 2021

2차원 유동장내 수직 진동하는 원통의 Von Karman 와열 유동 현상에 대한 진동 주파수 계산 문제는 진동하는 물체의 비정상 공력 해석 연구 검증에 많이 사용하는 고전적 방법이다. 본 연구에서는 오픈소스 OpenFoam 기반의 중첩격자 기법을 사용하여 층류 유동장내의 수직방향 진동하는 원통 주변의 비정상 유동 현상과 원통 벽면에서의 공력 특성 변화를 해석하기 위한 일련의 해석 단계들과 결과를 타 연구그룹과 비교하였다. 원통 형상과 진동에 의한 와열 유동의 주기적 유동 특성과 복잡성 해석의 건전성을 확보하기 위하여 격자와 시간제어에 대한 해의 정확도에 미치는 영향을 평가하였다. 본 연구에서 수행한 해석 방법은 일관성과 신뢰성 있는 해석 결과들 보여주었으며, 향후 보다 실제적인 진동하는 에어 포일의 비정상 공력 해석 연구에 적용 가능함을 확인하였다.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.11 no.5
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• pp.15-26
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• 2012

Government agencies including the national police agency have executed diverse efforts including continuous improvements of traffic facilities and operation methods, education, enforcements in order to improve traffic operation systems; nevertheless there have been continuous criticisms on irrationality in traffic signal and road facility operation. One of the reasons may be the lack of systematic preliminary evaluations on various alternatives. However, there was no appropriate tool to evaluate the mobility and safety of thus alternatives in a systematic way. Therefore, this study proposes the systematic use of microscopic traffic simulation models as a comprehensive evaluation tool. In addition, this study verified the potential of using a microscopic traffic simulation model using the case of operating an overlap phase on a shared-left-turn lane through a systematic way where the evaluation was conducted through data collection, building networks, calibrating microscopic simulation models, producing performance measures, evaluating mobility and safety, and so on. As a result, the operation of overlap phase on a shared-left-turn lane showed no big difference from other operation scenarios such as leading left-turn on exclusive left turn lane in terms of mobility. However the operation of overlap phase on a shared-left-turn lane decreased safety by increasing potential conflicts.

• The Journal of Korean Association of Computer Education
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• v.8 no.1
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• pp.93-103
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• 2005

Since the most program execution time is consumed in a loop structure, extracting parallelism from sequential loop programs is critical for the faster program execution. Conventional studies for extracting the parallelism are focused mostly on a uniform data dependence distance. In this paper, we proposed data dependency elimination method for a nested loop and extended data dependency elimination method to extract parallelism from the loop with procedure calls. The data dependency elimination method and the extended data dependency elimination method can be applied to uniform and non-uniform data dependency distance. We compared our method with conventional methods using CRAY-T3E for the performance evaluation. The results show that the proposed algorithms are very effective.

• Journal of Korean Orthopaedic Sports Medicine
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• v.9 no.2
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• pp.85-90
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• 2010

Purpose: To evaluate the results of percutaneous lateral release and arthroscopic medial plication for patients with recurrent patella dislocation. Materials and Methods: This study includes the thirty-one cases of patients who have had a surgical operation from March 2001 to March 2008. All the patients had recurrent patella dislocation after trauma history. The average age was 24.2 years old and the average follow up was 47.4 months (minimum 24 months). Results: The preoperative congruence angle, lateral patellofemoral angle, Lysholm score was $24.8^{\circ}$, $-6.2^{\circ}$, 75 points on average respectively. However, the postoperative congruence angle, lateral patellofemoral angle, Lysholm score was improved to normal range: $-2.8^{\circ}$, $10.2^{\circ}$, 95 points on average. Five cases showed the recurrent dislocation after operation. Among them, three cases showed femoral trochlear dysplasia. Conclusion: Percutaneous lateral release and arthroscopic medial plication showed satisfactory results for recurrent patella dislocation with low complication rate. However, in cases with femoral trochlear dysplasia, another surgical treatment may be considered.

• Spatial Information Research
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• v.6 no.2
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• pp.247-256
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• 1998

The objective of this research was to develop habitat suitability models for wild boar (Sus Scrafa) in Mt. Sulak National Park and Mt. Jumbong Natural Forest Reserve. The study area is covered-with climax temperate hardwood forests ot'mainly Mongolian oak ($\textit{Quercus mongolica}$), and has diverse wildlife species including wild boars. Three suitability models - summer, fall, and annual models - were developed. These models were based on slope, aspect, forest types, forest year classes, distance from streams and trails. Habitat data collected through telemetry were used for the models. The accuracy of the models was tested by comparing observed traces of wild boar in Mt. Jurnbong, and most traces were on suitable areas on the suitability maps.