• Ocean and Polar Research
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• 제24권4호
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• pp.491-500
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• 2002

Magnetic anomalies in the Dokdo and it's surroundings were investigated with respect to structure and origin of the Dokdo and surrounding seamounts. After normal and diurnal correction of measured magnetic data, crossover correction was applied to reduce errors between sets of magnetic anomalies. The errors from crossover operation result in decrease of about 51%, from 62.2 nT to 30.1 nT in standard deviation. Reduction-to-the-pole, second vertical derivative and analytic signal processing were applied to explore magnetic anomaly signatures in detail. Magnetic anomalies are most complicated in the 1st-Dok seamount, show SWW-NEE linear pattern in the 2nd-Dok seamount and lower to the 3rd-Dok seamount. Different magnetic anomaly patterns in three seamounts imply that three volcanic seamounts were formed at different times and are composed of rocks that were produced in different conditions. It seems that the 3rd-Dok seamount was first to form and followed by the 1st-Dok seamount. The complicated magnetic and second vertical derivative anomaly patterns in the 1st-Dok seamount may be due to subsidiary cones around crater or the presence of intruded magma bodies below sea surface and the Dokdo is probably a marginal subsidiary part of crater.

• 대한수학회지
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• 제36권4호
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• pp.787-811
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• 1999

Let M be the maximal ideal space of the Banach algebra $H^{\infty}$ of bounded analytic functions on the open unit disc $\triangle$. For a positive singular measure ${\mu}\;on\;{\partial\triangle},\;let\;{L_{+}}^1(\mu)$ be the set of measures v with $0\;{\leq}\;{\nu}\;{\ll}\;{\mu}\;and\;{{\psi}_{\nu}}$ the associated singular inner functions. Let $R(\mu)\;and\;R_0(\mu)$ be the union sets of $\{$\mid$\psiv$\mid$\;<\;1\}\;and\;\{$\mid${\psi}_{\nu}$\mid$\;<\;0\}\;in\;M\;{\setminus}\;{\triangle},\;{\nu}\;\in\;{L_{+}}^1(\mu)$, respectively. It is proved that if $S(\mu)\;=\;{\partial\triangle}$, where $S(\mu)$ is the closed support set of $\mu$, then $R(\mu)\;=\;R0(\mu)\;=\;M{\setminus}({\triangle}\;{\cup}\;M(L^{\infty}(\partial\triangle)))$ is generated by $H^{\infty}\;and\;\overline{\psi_{\nu}},\;{\nu}\;{\in}\;{L_1}^{+}(\mu)$. It is proved that %d{\theta}(S(\mu))\;=\;0$ if and only if there exists as Blaschke product b with zeros $\{Zn\}_n$ such that $R(\mu)\;{\subset}\;{$\mid$b$\mid$\;<\;1}\;and\;S(\mu)$ coincides with the set of cluster points of $\{Zn\}_n$. While, we proved that $\mu$ is a sum of finitely many point measure such that $R(\mu)\;{\subset}\;\{$\mid${\psi}_{\lambda}$\mid$\;<\;1}\;and\;S(\lambda)\;=\;S(\mu)$. Also it is studied conditions on \mu for which $R(\mu)\;=\;R0(\mu)$.

• 정보처리학회논문지A
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• 제12A권3호
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• pp.243-252
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• 2005

본 논문에서는 최소제곱 추정기법과 로버스트 추정기법을 사용하여 다중 프로세서 시스템에서의 데이터 통신의 빈도를 모델링하는 방법을 제안한다. 몇 가지의 서로 다른 크기의 작은 입력 데이터들을 작업부하 프로그램에 부과하여 그때마다의 통신 빈도를 측정하고, 이 측정된 값들에 두 가지 통계적 추정기법을 순차적으로 적용함으로써 통신 빈도를 정확히 예측할 수 있는 모델을 구축하는 방법이다. 이 모델링 기법은 작업부하나 목표시스템의 구조적인 사양에 무관하게 입력 데이터의 크기에만 의존하므로 다양한 작업부하와 목표시스템에 대하여 그대로 적용할 수 있는 장점이 있다. 또한 목표시스템에서 작업부하의 알고리즘적 동적특성이 수학적인 공식으로 반영되므로 데이터 통신이외의 성능 데이터를 모델링하는 데에도 적용할 수 있다. 본 논문에서는 대표적인 다중 프로세서인 공유메모리 시스템에서 데이터 통신을 유발하는 핵심 요소인 캐시접근실패의 빈도에 대한 모델을 구하였으며, 12번의 실험 중 5번의 경우에는 $1\%$ 미만, 나머지 경우에는 $3\%$ 내외의 대단히 정확한 예측 오차율을 보였다.

• Journal of Computing Science and Engineering
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• 제5권2호
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• pp.111-120
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• 2011

Data mining algorithms should exploit new hardware technologies to accelerate computations. Such goal is difficult to achieve in database management system (DBMS) due to its complex internal subsystems and because data mining numeric computations of large data sets are difficult to optimize. This paper explores taking advantage of existing multithreaded capabilities of multicore CPUs as well as caching in RAM memory to efficiently compute summaries of a large data set, a fundamental data mining problem. We introduce parallel algorithms working on multiple threads, which overcome the row aggregation processing bottleneck of accessing secondary storage, while maintaining linear time complexity with respect to data set size. Our proposal is based on a combination of table scans and parallel multithreaded processing among multiple cores in the CPU. We introduce several database-style and hardware-level optimizations: caching row blocks of the input table, managing available RAM memory, interleaving I/O and CPU processing, as well as tuning the number of working threads. We experimentally benchmark our algorithms with large data sets on a DBMS running on a computer with a multicore CPU. We show that our algorithms outperform existing DBMS mechanisms in computing aggregations of multidimensional data summaries, especially as dimensionality grows. Furthermore, we show that local memory allocation (RAM block size) does not have a significant impact when the thread management algorithm distributes the workload among a fixed number of threads. Our proposal is unique in the sense that we do not modify or require access to the DBMS source code, but instead, we extend the DBMS with analytic functionality by developing User-Defined Functions.

• 한국환경과학회지
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• 제13권12호
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• pp.1023-1032
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• 2004

Rapid progress in urbanization has resulted in a change of the micro climate, especially in the urban area. In order to investigate the phenomenon of the heat island in the residential micro climate, a field survey was carried out by 4 sets of the residential type in Jeonju under typical winter synoptic condition. As analytic methode, it is used the comparison on the relation of the Land-to-Coverage Rate to Heat Island and Oxygen Concentration. And as a key question it is asked how stable characteristics of the micro climate will result from the survey of the Heat Island and the Oxygen Concentration, used as indicator. To ensure the trustworthy result of research, it is calculated the critical influence of the wind velocity and the Land-to-Covearage Rate. As a result of comparative analysis, it could be confirmed that the local temperatures in all sets of the residential type were higher than the average temperature in Jeonju. But the housing type A 'exclusive use for housing zone' has relativly the most stable and best living condition. On the contrary the residential type B and D has the worst toward the oxygen concentration in the time zone 9-12 a.m., which didn't reach the minimum of the oxygen concentration $20.5{\%}.$ It means that the higer the development and population density is, the worse is the situation of the Quality of Life in the residential types in accordance with the heat island and oxygon con­centration.

• 대한환경공학회지
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• 제34권1호
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• pp.23-31
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• 2012

새만금 유역은 BOD와 TP의 비점오염배출 비중이 각각 68.4와 61.4% (2009년 기준)로 점오염원에 비해 높게 나타나므로 새만금 수질관리를 위해서는 비점오염원에 대한 대책수립이 시급하다. 본 연구에서는 새만금 유역 최적관리기법 대상지 선정을 위해 비점오염원의 영향이 큰 농업지역을 중심으로, 그리고 부영양화에 주요인자인 총인(TP)을 기준으로 농업비점오염대책 우선지구를 선정하고자 하였다. 우선지구 선정방안은 의사결정에 의한 오염영향 지수를 이용한 정성분석 방법으로 수계에 비점오염원(TP기준)이 작용하는 단계를 크게 발생, 배출, 유출 관련지표로 구분하여 비점오염원 영향지수(NPSI; Non-point Source Index)를 산정하였으며, 전문가 AHP (Analytic Hierarchy Process)분석을 통해 지표의 가중치를 결정하였다. NPSI 산정에는 행정구역 745개의 동리단위 기준으로 비점발생특성(해당 지역의 액비살포 면적, 축사 면적, 논면적, 밭면적, 인산질 비료사용량), 비점배출특성(수질오염 총량관리제의 축산계 비점오염원 배출부하량, 토지계 배출부하량), 비점유출특성(토양유실량, 불투수율, 유출곡선지수, 유달거리, 유효강우비)의 총 12개의 지표가 적용되었다. GIS (Geographical Information System) 분석을 이용한 NPSI 산정결과 새만금 유역 농업비점관리지역 우선지구 후보지로 만경강 5지점과 동진강 5지점을 선정하였다. 우선지구 후보지의 선정원인은 주로 축산에서 기인한 것으로 나타났으며, 이는 AHP 분석결과 축산관련 지표의 가중치가 높았기 때문으로 사료된다.

• KIEAE Journal
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• 제11권4호
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• pp.63-70
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• 2011

In respond to the global energy crisis and climate change, there have been many ongoing national efforts to develop a sustainable housing prototype followed by "2 million Green Home Project" in Korea. More than 50% of nation's population are currently living in apartment housing thus the country is seriously in need of developing green apartment prototype. In this research, we focused on energy-conservative green apartment design prototype that have both passive components and active systems explored in a systemic design approach. After selecting an existing basic apartment unit, we analyzed and compared statistical data with the simulated annual energy consumption to match these two data sets for validating simulation accuracy performed with TRNSYS package. We performed energy simulations with different passive design factors such as varied insulation thickness, window types and infiltration rates as well as the active design factors including boilers and lighting fixtures to analyze their impacts on the energy performance of the housing unit using TRNSYS software. As a result, we acquired significant energy reduction effect with explored design strategies but the life cycle cost analysis for the final design guidline would need to be performed. In this study, we focused on a systematic comparative energy analysis based on TRNSYS that can improve the design of a green apartment housing.

• Asia pacific journal of information systems
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• 제7권1호
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• pp.85-97
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• 1997

This paper is concerned with knowledge representation schemes best suited for human resource management (HRM) problem domains including human resource planing, selection, placement, compensations, performance evaluation, training and labor-management relations. In order to suggest the scheme we consider two research gods. First, we evaluate and prioritize. The knowledge representation techniques of frames rules, semantic nets and predicate logic that hove been recommended to managerial domains. The combined Analytic Hierarchy Process technique is employed to combine individual judgments effectively between two different expert groups. As a result if we are to select a single knowledge representation technique, a frame representation is best for most HRM domains and to combine frames with others is another choice. Second as a strategy for knowledge representation schemes we show some examples for each damn in terms of labeled semantic nets and two types of rules derived from the semantic nets. We propose nine knowledge components as ontologies. The labeled semantic nets con provide some benefits compared with conventional one. More clearly definea node rode information maces it easy to find the ac information. In the rule sets, the variables are the node of the semantic nets. The consistency of rules is validated by the relationship of the knowledge components.

• 한국통신학회논문지
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• 제24권7B호
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• pp.1268-1278
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• 1999

본 논문에서는 ATM 망에서 VBR MPEG 비디오 트래픽에 대한 리키버킷 기반의 UPC 제어 시 적절한 트래픽 기술자 조합을 선정할 수 있는 해석적 방법을 제안한다. 장면기반 비디오 트래픽 모델링을 통해 UPC에서의 셀 위반확률을 해석적으로 유도하고, 이를 이용하여 원하는 UPC 제어 위반확률을 갖는 트래픽 기술자의 조합을 선정할 수 있음을 보인다. 실험 대상 MPEG 비디오 시퀀스에 대해 본 논문에서 제안한 해석적 트래픽 기술자 dimensioning 결과가 실제 시뮬레이션에 의한 선정결과를 잘 근사화 함을 모의실험을 통해 보인다. 마지막으로 망에서 호 수락제어로 ON/OFF 소스의 등가대역폭을 이용할 경우, 가능한 트래픽 기술자 조합에 대해 할당되는 등가대역폭을 분석하여 효율적인 트래픽 기술자 선정방안을 제안한다.

• 대한기계학회논문집A
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• 제20권1호
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• pp.163-171
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• 1996

For the effective analysis of two dimensional plane problems, Treffiz finite elements and cavity elements have been proposed. These element matrix equaitons were formulated on the basis of hybrid variational principle and Treffiz function sets derived consitstently from the complex theoy of plane elasticity. In order to suggest the accuracy chatacteristics of the proposed Treffiz elements typical plane problems were analyzed and these results were compared with ones obtained by using the conveintional displacement type elements. The accuracy of the proposed elements is less sensitive to the element size and shape than the conventional displacement type elements. These elements, being able to be formed with multi-nodes, give the convenient modeling of an analytic domain. The cavity elements give the comparatively exact values of stress concentration factors of stress intensity factors and can be effectively used for the analysis of mechanical stuctures containing various cavities.