• Geomechanics and Engineering
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• 제5권1호
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• pp.17-36
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• 2013

Settlement of the piled raft can be estimated even after years of completing the construction of any structure over the foundation. This study is devoted to carry out numerical analysis by the finite element method of the consolidation settlement of piled rafts over clayey soils and detecting the dissipation of excess pore water pressure and its effect on bearing capacity of piled raft foundations. The ABAQUS computer program is used as a finite element tool and the soil is represented by the modified Drucker-Prager/cap model. Five different configurations of pile groups are simulated in the finite element analysis. It was found that the settlement beneath the piled raft foundation resulted from the dissipation of excess pore water pressure considerably affects the final settlement of the foundation, and enough attention should be paid to settlement variation with time. The settlement behavior of unpiled raft shows bowl shaped settlement profile with maximum at the center. The degree of curvature of the raft under vertical load increases with the decrease of the raft thickness. For the same vertical load, the differential settlement of raft of ($10{\times}10m$) size decreases by more than 90% when the raft thickness increased from 0.75 m to 1.5 m. The average load carried by piles depends on the number of piles in the group. The groups of ($2{\times}1$, $3{\times}1$, $2{\times}2$, $3{\times}2$, and $3{\times}3$) piles were found to carry about 24%, 32%, 42%, 58%, and 79% of the total vertical load. The distribution of load between piles becomes more uniform with the increase of raft thickness.

• 한국환경과학회지
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• 제13권8호
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• pp.733-737
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• 2004

FThe aim of this study was to carry out a preliminary test of the air quality modelling system (HIRES-AIRCHEM) developed at The University of New South Wales, particularly with regard to the forecast ozone distribution. This was achieved by assimilating the New South Wales State Environment Protection Authority (EPA) emissions inventory, consisting of road and non-road sources, and running the system over the Sydney metropolitan area for the four day period 25-28 February 1998. During this period ozone readings exceeded the EPA's goal of 8pphm on several occasions. The model forecasts of ozone distribution verified well with the EPA's ozone readings. This result has important implications for possible future use of the system as a tool for routinely predicting and assessing air quality.

• 융합보안논문지
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• 제2권2호
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• pp.179-187
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• 2002

그리드는 지리적으로 흩어져 있는 이종의 자원들을 고속 네트워크로 연결하여 협업하기 위한 기반구조이다. 그리드 응용의 수행되기 위해서는 먼저 네트워크의 안정성과 신뢰성이 보장되어야 함으로 네트워크 자원들은 관리되어야 한다. GMA는 대규모 분산된 자원의 모니터링을 위한 효과적인 구조를 제안한다. 본 논문에서는 GMA를 기반으로 실제적이고 전체적인 네트워크 관리를 위한 웹 기반 그리드 네트워크 관리 시스템을 설계하였다. 그리드 네트워크 관리 시스템은 여러 분산된 관리 시스템을 스스로 유지시키면서 연결할 수 있어야 한다. LDAP 인증을 이용하여 시스템 접근에 대해 관리자 인증을 수행하여 그리드 네트워크 관리 시스템의 안정성을 보장한다.

• 천문학회보
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• 제42권2호
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• pp.63.3-64
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• 2017

KIC6118779 is an over-contact binary system having a short orbital period of about 0.36 days. The photometric data for this system are acquired by the observations of Kepler mission in the long cadence mode having a time resolution of about 30 minutes. It means that the Kepler light curves of the system may be strongly affected by phase smearing effect and the analysis of them without consideration of the phase smearing effect may result in wrong stellar properties. Additionally, this system also shows dynamical variation of light curve resulting from spot activity. For all those reasons, it is difficult to investigate KIC6118779, and the investigation should be carried out carefully. In this presentation, we introduce the phase smearing effect and carry out the light curve modeling with the 2015 version of the Wilson-Devinney binary code considering the phase smearing effect. Our results show that the system is a deep over contact binary system and has extremely low mass ratio of about 0.12. Moreover our spot modeling implies the cyclic migration of a big cool spot on the massive component.

• Structural Engineering and Mechanics
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• 제6권4호
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• pp.427-437
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• 1998

Flat plate constructions are structural systems which are directly placed on columns without any beams. Various solution methods have been introduced for the solution of flat plate structures under horizontal and vertical loads. In most of these solution methods, models comprising of one column and one plate have been studied. In other solutions, however, co-behavior of two reciprocal columns has been investigated. In this study, interrelations of all the columns on one storey have been examined. At the end of the study structure consisting of nine columns and four plates has been chosen as a model. Then unit moment has been successively applied to each of these columns and unit moments carried over the other columns have been found. By working out solutions far plates and columns varying in ratio, carry-over factors have been found and these factors given in tables. In addition, fixed-end moment factors on the columns arising due to vertical load were also calculated. Then citing slope-deflection equations to which these results could be applied, some examples of moment and horizontal equilibrium equations have been given.

• Structural Engineering and Mechanics
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• 제4권1호
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• pp.49-59
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• 1996

This paper considers large deflection problem of a simply supported beam with variable are length subjected to a point load. The beam has one of its ends hinged and at a fixed distance from this end propped by a frictionless support over which the beam can slide freely. This highly nonlinear flexural problem is solved by elliptic-integral method and shooting-optimization technique, thereby providing independent checks on the new solutions. Because the beam can slide freely over the frictionless support, there is a maximum or critical load which the beam can carry and it is dependent on the position of the load. Interestingly, two possible equilibrium configurations can be obtained for a given load magnitude which is less than the critical value. The maximum arc-length was found to be equal to about 2.19 times the fixed distance between the supports and this value is independent of the load position.

• 한국실내디자인학회:학술대회논문집
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• 한국실내디자인학회 2007년도 추계학술발표대회 논문집
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• pp.198-201
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• 2007

Currently, both Korea and Japan have cooperated to get a foothold in economic major countries in the Asia through the various economic cooperation and the overcoming of cultural difference in cultural interchanges between two countries. However, in the present age, two countries are on the other road in historical view and conception; the final report over 3 year studies by the two countries' history study partnership commission shows the above views; while Korea has been in base of Japan colonialization's unjustification, Japan has been in base of its facts. The aboves have proved that Japan has not taken an honest self examination and conscience over the history. Accordingly, Japan resistance volunteer memorial is proposed as the educational place to carry down the martyr's holy patriotism in later ages and practice its spirit by learning the resistance volunteer resistance volunteer movement, which focused on resisting the Japan invasion and fighting the independence.

• 핵의학기술
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• 제14권2호
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• pp.197-202
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• 2010

목적: 각 검사실에서는 임상의 신속한 검사 결과 보고 요청에 부응하고 검사 결과의 신뢰도 및 효율성을 증가시키기 위해 자동화 장비를 많이 사용한다. 국산 자동화 장비는 기존 자동화 장비의 단점을 개선, 보완하여 폭넓은 수행능을 가진 국산 자동화 장비이다. 본 연구에서 국산 자동화 장비와 기존 자동화 장비와의 상관성 및 분석능력을 평가하여 검사실에서의 결과보고시간 단축에 대한 유용성과 신뢰성을 알아보고자 하였다. 대상 및 방법: 2009년 9월 삼성서울병원에서 갑상선 호르몬 검사(TT3, TSH, FT4)가 의뢰된 환자를 대상으로 저농도에서 고농도 검체 100개씩 국산 자동화 장비와 RIA-mat 280을 사용하여 상관성을 알아보았다. 국산 자동화 장비의 부분별 평가로 첫째, Tip부분은 정확도, 회수율, 검체 간 상호 오염도를 측정하였다. 둘째, Incubator부분은 회전수(RPM)와 회전축 원경(mm)에 따른 최적의 검사반응 조건을 알아보았다. 검체처리 속도를 분석하기 위해 특정기간의 검사결과 보고시간을 조사하였다. 결과: 국산 자동화 장비와 RIA-mat 280의 상관계수($R^2$)는 TT3 0.98, TSH 0.99, FT4 0.92로 좋은 상관관계를 보였다. Tip의 평가로 정밀도 CV 0.38 %(1번 Tip), CV 0.39 %(2번 Tip), 정확도 98.3 %(1번 Tip), 98.6 %(2번 Tip). 검체 간 상호 오염도는 0.01 %(1번 Tip), 0 %(2번 Tip)로 검체 간 상호 오염도가 거의 없었다. Incubator 조건에서 회전수(RPM)와 회전수 원경(mm) 500 RPM의 1.0 mm, 1.5 mm와 600 RPM의 1.0 mm, 1.5 mm 중 600 RPM의 1.0 mm가 최상의 조건임을 알 수 있었다. 기존의 자동화 장비에서 6회/일 시행되던 검사가 최대20회/일로 늘어남으로써 검체 접수에서 결과보고까지 소요시간이 평균 4.20시간에서 평균 2.19시간으로 약 2시간 단축되었다. 결론: 국산 자동화 장비(Gamma Pro) 사용으로 결과보고 시간이 평균 2.19시간으로, 약 2시간 단축되는 결과를 얻었다. 본 기기는 일정시간당 대량 검체 처리능력이 뛰어나고 실용성을 갖춘 효율적인 장비라고 여겨진다. 검사결과 보고 시간 단축으로 인해 응급환자의 신속한 진단과 외래환자의 진료대기시간 단축에 유용할 것이다.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제11권2호
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• pp.846-864
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• 2017

Software Defined Network (SDN) realizes management and control over the underlying forwarding device, along with acquisition and analysis of network topology and flow characters through south bridge protocol. Data path Identification (DPID) is the unique identity for managing the underlying device, so forged DPID can be used to attack the link of underlying forwarding devices, as well as carry out DoS over the upper-level controller. This paper proposes a dynamic defense method based on Client-Puzzle model, in which the controller achieves dynamic management over requests from forwarding devices through generating questions with multi-level difficulty. This method can rapidly reduce network load, and at the same time separate attack flow from legal flow, enabling the controller to provide continuous service for legal visit. We conduct experiments on open-source SDN controllers like Fluid and Ryu, the result of which verifies feasibility of this defense method. The experimental result also shows that when cost of controller and forwarding device increases by about 2%-5%, the cost of attacker's CPU increases by near 90%, which greatly raises the attack difficulty for attackers.

• 한국문헌정보학회지
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• 제31권3호
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• pp.165-208
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• 1997

온라인 열람목록의 이용자 인터페이스 특성이 이용행태에 미치는 영향을 파악하고, 이용자에게 보다 친근한 인터페이스를 평가하여 시스템 설계의 방향을 제시하는 데에 본 연구의 목적을 두었다. 이용자 인터페이스에 있어서 뚜렷한 특성상의 차이를 보이는 두 시스템을 대상으로 하여 $2\times2$ 교차계획법으로 이용행태연구를 위한 실험연구를 수행하였다. 65명의 탐색자가 실험에 참여하였다. $2\times2$ 교차계획법에서의 이월효과와 시스템효과, $\chi^2$검증, t 검증 매크네마 검증, 최대우도법을 통한 주변대칭성 검증, 인자분석, 회귀분석, 분산분석 등의 통계기법을 검증해야 할 가설과 데이터의 성격에 따라 적절히 적용하여 분석하였다.