• 대한기계학회논문집A
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• 제33권1호
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• pp.64-71
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• 2009

In this paper, a study on low-velocity impact response of honeycomb sandwich panels was done for the changes of impact location and core fabrication angles. The test specimens were made of glass/epoxy laminate facesheet and aluminum honeycomb core. Square samples of 100mm and 100mm sides were subjected under low-velocity impact loading using instrumented testing machine at three energy levels. Impact parameters like maximum force, time to maximum force, deflection at maximum force and absorbed energy were evaluated and compared for the changes of impact location and core fabrication angle. The impact damage size were measured at facesheet surface by 3-Dimensional scanner. Also, sandwich specimens after impact test were cut to analyse the failure mode.

• 한국공간구조학회논문집
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• 제23권3호
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• pp.71-78
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• 2023

Recently, Free-Form and Irregular Shape high-rise buildings are constructed by IT technology development. Tilted shaped high-rise building which is one of Irregular shape high-rise buildings can cause lateral displacement by gravity load and lateral load due to tilted elevation shape. Therefore, it is necessary to review the behavior and structural aspects of the Tilted shape high-rise building by gravity load. In this paper, the dynamic characteristics of a tilted structure with a dual-core were analyzed with the core location as a design variable, and response behavior, vulnerable members, and vulnerable layers to earthquake loads were analyzed. As a result of the analysis, as the location of the core moved in an tilted direction, the eccentric distance and eccentric load decreased, reducing the axial force of the vertical members. However, the location of the core had little effect on the response.

• KIEAE Journal
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• 제10권6호
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• pp.3-10
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• 2010

The subject is to find green roofs' location as stepping stones in green-network in fine scale. The study site is Junggu, Seoul, which has core areas(Bukaksan and Namsan) and green areas(parks, etc.). Through literature review, the closer to core areas and green areas, target species reach green roof easier, and target species must be avifauna(flying species) and high class in food chain, because of possibility of reaching. So, Great Tits, inhabited in Namsan and urban bird, is target species. The location standard of green roofs, realized birds' reaching distance, consists of home range(horizontal range and vertical range) and roof-greening capable area. The green roofs' distribution of location was resulted through GIS analysis of feasible site finding, and classified with weight of score. In discussion, Namsan gives more effect to locate green roofs than Bukaksan does and selected buildings which are grouped in some parts need to be managed with group, green roof district.

• Steel and Composite Structures
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• 제38권6호
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• pp.671-690
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• 2021

Seismic responses of RC core wall with two outriggers are investigated in this study. In the models analyzed here, one of the outriggers is fixed at the top of the building and the second is placed at different levels along the height of the system. Each of the systems resulting from the placement of the outrigger at different locations is designed according to the prescriptive codes. The location of the outrigger changes along the height. Linear design of all the structures is accomplished by using prescriptive codes. Buckling restrained braces (BRBs) are used in the outriggers and forward directivity near fault and far fault earthquake record sets are used at maximum considered earthquake (MCE) level. Results from nonlinear time history analysis demonstrate that BRB outriggers can change the seismic responses like force distribution and deformation demand of the RC core-walls over the height and lead to the new plastic hinge arrangement over the core-wall height. Plasticity extension in the RC core wall occurs at the base as well as adjacent to the outrigger levels. Considering the maximum inter-story drift ratio (IDR) demand as an engineering parameter, the best location for the second outrigger is at 0.75H, in which the maximum IDR at the region upper the second outrigger level is approximately equal to the corresponding value in the lower region.

• 한국통신학회논문지
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• 제25권1A호
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• pp.90-95
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• 2000

Ordered Core Based Tree (OCBT) 프로토콜에서 core 스위치의 위치는 성능에 영향을 끼치는 가장 중요한 요소이다. 본 논문에서는 여러 level의 core 스위치를 어디에 둘 것인가에 대한 방법을 연구한다. 제안된 알고리즘은 전체 네트워크는 3개의 논리적 계층-Small, Medium, Large-으로 나누어, 네트워크의 각 노드(라우터)들은 자기 이와의 다른 노드들로부터 자신의 노드까지의 최단경로 비용의 합을 계산한다. S지역에서 최소의 비용을 가지는 노드를 core노드로 만들고, 같은 M지역에 속한 S지역의 core 노드들은 다른 core 노드들로부터의 최단 경로 합을 계산해서 그 값이 가장 작은 노드가 레벨이 하나 높은 core 노드가 된다. 그리고 M지역에서의 core노드에서 같은 방법으로 가장 높은 레벨을 가지는 core노드를 정한다. 제안한 방법을 네트워크에서 core 노드를 정하는 두 가지 일반적인 방법과 비교한다. 첫 번째 방법은 random 방법으로 같은 수의 core 노드를 random하게 선정하는 방법이다. 두 번째 방법은 center 방법으로 각각의 S지역에서 중심에 가까운 노드를 core 노드로 만들고, M지역이나 L 지역에서의 core는 하위 레벨 core 중에서 해당 熾だ\ulcorner중심에 가까운 core로 결정한다. 시뮬레이션을 통하여 제안한 방법이 mean tree cost와 join latency관점에서 비교된 다른 방법들 보다 우월한 성능을 가지는 것을 확인할 수 있었다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2003년도 컴퓨터소사이어티 추계학술대회논문집
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• pp.179-182
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• 2003

In this paper, we developed those OpenLS(Open Location Service) Core Services based on the Web-Service, because Web-Service environments provide a suitable method to gather requested information in an appropriate way. The proposed architecture cooperate with OpenLS Core Services( Directory Service, Location Utility Service and Router Determination service) and is an interoperability one - it identifies those global elements of the global Web-Services network that are required in order to ensure interoperability between Web-services. In this paper, a new architecture of OpenLS Core Services is proposed and tested in OpenLS Core Services environments.

• 정보처리학회논문지A
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• 제13A권5호
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• pp.435-444
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• 2006

위치기반서비스(LBS: Location-Based Services)의 이용자가 급증함으로써 최근 위치 트리거(Location Trigger) 서비스에 대한 다양한 응용분야가 등장하고 있다. 위치 트리거는 사용자의 이동 위치를 감지하여 특정한 지역에 진입, 존재, 이탈할 경우 사용자에게 단문문자서비스(SMS), 전자메일 등을 통하여 알리거나 또는 사용자에 의해 미리 정의된 특정한 서비스를 제공하는 기술이다 기존에 이러한 위치 트리거 기술은 위치 제공 서버에 주기적으로 위치정보를 요청하여 처리해 왔으나 LBS 서비스 가입자가 증가할수록 서버 및 통신 부하로 인하여 시스템의 성능 저하를 초래하게 된다. 이에 본 논문에서는 위치 트리거를 처리함에 있어서 이동통신망의 위치서버의 부하를 줄이고 모바일 단말기에 임베디드 된 GPS 디바이스의 전력 소모량을 최소화하는 멀티레벨 위치 트리거 방법에 대하여 연구하였다. 실제 본 논문에서 제시하는 방법을 설계하고 테스트베드를 구축하여 성능을 평가함으로써 위치 트리거 기술의 성능 향상에 기여하였다.

• 한국안전학회지
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• 제33권2호
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• pp.8-13
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• 2018

The light weight composite materials have been replacing in high performance structures. The object of this study is to examine the effects of the initial crack location about a delamination in a PVC foam cored sandwich composite that is used for the strength improvement of structures. The initial crack location and fiber laminates thickness were changed with several types. The MMB specimen was used for evaluating the fracture toughness and crack behaviors. The material used in the experiment is a commercial twill carbon prepreg in CFRP material and Airex in PVC foam core. Sandwich laminate composites are composed by PVC foam core layer between CFRP face sheets. The face sheets were fabricated as 2 types of 5 and 8 plies. The initial cracks were located in a PVC form core and the interface of upper CFRP sheet. From the results, the crack initiation was affected with the location of the initial crack inserted in the PVC foam core. Among them, the initial crack at 1/3 of the upper part of the PVC foam core was the most rapid progression. And the critical energy release rate was $0.40kJ/m^2$, which is the lowest value when the initial crack was inserted into the interface between a PVC foam core and CFRP laminated with 5 plies. Meanwhile, the highest value of $1.27kJ/m^2$ was obtained when the initial crack was located at the center line in case of the 8 plies.

• Journal of Computing Science and Engineering
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• 제5권4호
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• pp.283-287
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• 2011

Due to the proliferation of software parallelization on multi-core CPUs, the number of concurrently executing processes is rapidly increasing. Unlike processes running in a server environment, those executing in a multi-core desktop or a multi-core mobile platform have various correlations. Therefore, it is crucial to consider correlations among concurrently running processes. In this paper, we exploit the property that for a given created location in the binary image of the parent process, the average running time of child processes residing in the run-queue differs. We claim that this property can be exploited to improve the overall system performance by running processes that have a relatively short running time before those with a longer running time. Experimental results verified that the running time was actually improved by 11%.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2005년도 Proceedings of ISRS 2005
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• pp.317-320
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• 2005

The LBS (Location-Based Services) are valuable information services combined the location of moving object with various contents such as map, POI (point of Interest), route and so on. The must general service of LBS is route determination service and its applicable parts are FMS (Fleet Management System), travel advisory system and mobile navigation system. The core function of route determination service is determination of optimal route from source to destination in various environments. The MODB (Moving Object Database) system, core part of LBS composition systems, is able to manage current or past location information of moving object and massive trajectory information stored in MODB is value-added data in CRM, ERP and data mining part. Also this past trajectory information can be helpful to determine optimal route. In this paper, we suggest methods to determine optimal route by querying past trajectory information in MODB system and verify the effectiveness of suggested method.