• 디지털산업정보학회논문지
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• 제6권2호
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• pp.107-118
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• 2010

This paper proposes a digital forensic method to a file creation transaction using a journal file($LogFile) on NTFS File System. The journal file contains lots of information which can help recovering the file system when system failure happens, so knowledge of the structure is very helpful for a forensic analysis. The structure of the journal file, however, is not officially opened. We find out the journal file structure with analyzing the structure of log records by using reverse engineering. We show the digital forensic procedure extracting information from the log records of a sample file created on a NTFS volume. The related log records are as follows: bitmap and segment allocation information of MFT entry, index entry allocation information, resident value update information($FILE_NAME, $STANDARD_INFORMATION, and INDEX_ALLOCATION attribute etc.).

• 한국정밀공학회지
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• 제16권11호
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• pp.234-242
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• 1999

In this paper, a method for assessment of the anisotropic machined surfaces is proposed. Fractal dimension (FD) is calculated using structure function and an index of the anisotropy is obtained as a ratio of its maximum and minimum value. The upper limit of fractal region on the structure function is determined as the length of the lag where the autocorrelation function shows 20% of its maximum value. The model of the structure function is derived from that of the auto correlation function. And, it shows that the new method and the proposed index of anisotropy are useful.

• 한국해양공학회지
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• 제30권4호
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• pp.287-293
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• 2016

This paper presents an effective damage detection method for offshore jackets using natural frequency change ratios. Two parameters, cosine similarity and magnitude index, are considered to estimate the location and severity of the damage in the structure. A numerical jacket structure model is considered to verify the performance of the proposed method. As observed through analysis, the damages in the structure are detected accurately.

• 유통과학연구
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• 제18권2호
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• pp.59-67
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• 2020

Purpose: This study examines the relationship between formation of employment subcenters and regional industrial structures in Incheon. Research design, data, and methodology: We used the five-year panel data from 2012 to 2016 in 146 basic municipal units of Incheon to analyze panel regression models. Gross employment density and employment to population ratio were used as indicators of employment subcenters formation. The entropy index and Hachman index were used for analyzing the diversity and heterogeneity of industrial structures. Result: The analyses of two panel regression models showed that for the formation of employment subcenters, both the Entropy and Hachman index were significantly negative in most models. But tertiary industry was shown to have a significant positive relationship in all models. In the wholesale and retail sector, it was found that the average number of employees in the employment subcenters is significantly higher than that in the non-employment subcenters. Conclusions: The specialization of the industrial structure rather than the diversification contributes to the formation of the employment subcenters in Incheon. In particular, it can be considered that the wholesale and retail sector plays a very important role in forming the employment subcenters in many areas of Incheon.

• 인터넷정보학회논문지
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• 제11권1호
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• pp.15-20
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• 2010

본 논문은 무선 브로드캐스트 환경에서 인접한 노드들로부터의 정보를 활용하여 질의접근시간과 에너지소모를 줄이기 위한 인덱스 기법을 소개한다. 우리는 정보의 선별적 청취를 위해 HLBS라 불리는 3-계층 위치기반 순차적 접근방식의 인덱스를 제안한다. HLBS는 객체들의 위치를 참고한 순차적인 접근탐색 구조를 통해 포인터 없이 모든 객체의 인덱스를 구성한다. HLBS는 단순하고 적은 크기의 인덱스 구조로 무선 브로드캐스트 채널에서 효율적인 정보탐색을 지원한다. 시뮬레이션을 통해 제안 기법의 효율적인 정보검색의 성능을 증명하였다.

• 한국정보통신학회논문지
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• 제11권3호
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• pp.523-531
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• 2007

본 논문에서는 이동체들을 관리하기에 적합한 새로운 색인 기법을 개발하고, 이 기법의 비용 모델을 제안한다. 또한 삽입/삭제 비용이 적은 동적 해싱 색인을 제안한다. 동적 해싱 색인 구조는 해쉬와 트리를 결합한 동적 해싱 기술을 공간 색인에 적용한 것이다. 본 논문에서는 이동체의 빈번한 위치 변경에 대한 비용 모델과 동적 색인 구조를 분석하였고, 성능 평가 실험을 통하여 검증하였다. 실험 결과에서 새로이 제안하는 색인 기법(동적 해싱 색인)은 R-tree와 고정 그리드 보다 성능이 우수하였다.

• 한국산림과학회지
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• 제97권5호
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• pp.501-507
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• 2008

The data of crown width with 4 directions, DBH, tree height, and coordinate for sample trees were collected from 30 permanent sample plots in secondary fore st of the Maoershan Experimental Forestry Farm, Northeast China. In this paper, the competition of individual trees in stand were discussed for secondary forest by using iterative Hegyi competition index and crown overlap index that represented the competitive and cooperative interactions among neighboring trees. Active competitors of subject tree in the competition zone were selected to calculate the iterative competition index. Using the results of crown classification based on the equal crown projection area, a new distance dependent competition index called crown overlap index (COI) was developed for secondary forest. The COI performed well in describing the crown competition rather than crown competition factor (CCF). The individual-based competition index discussed in this paper will provide more precise for developing individual tree growth models for secondary forest and it can also use to adjust the stand structure for spatial optimal management.

• 대한전기학회논문지:전력기술부문A
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• 제53권9호
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• pp.487-493
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• 2004

The electric power industry throughout the world is undergoing considerable changes from the vertically integrated utility structure to the deregulated market. However, the deregulated electricity market is operated with respect to theory of economical efficiency, and therefore, the system operator requires data with fast contingency ranking for security of the bulk power system. This paper compares the weather dependant probabilistic risk index(PRI) with the system performance index for power flow in the IEEE-RTS. The system performance index for power flow presents the power system stability. This paper presents fast calculation method for determining contingency ranking using the weather dependant probabilistic risk index(PRI). The probabilistic risk index can be classified into the case of normal and adverse weather. This paper proposes calculation method using the probabilistic risk index in determining contingency ranking required for security under the deregulated electricity market.

• 한국항공운항학회지
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• 제18권1호
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• pp.89-99
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• 2010

The purpose of this study is analysis of Korean peninsula aircraft turbulence using the numerical weather prediction model, KWRF with the various turbulence index and pilot weather report data. Compared with the pilot weather report data and Calculated the turbulence index using the KWRF model result, many turbulence index show the similar horizontal distribution, except for the TUB2 and VWS. The analysis of vertical structure of turbulence, there are some difference each turbulence index respectively, but severe turbulence turn up in 15,000ft almost turbulence index. above 20,000ft height, intensity of turbulence vary each turbulence index. Through this turbulence study, It is founded on the research and development of the Korean peninsula aircraft turbulence

• 산업경영시스템학회지
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• 제25권4호
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• pp.61-68
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• 2002

This paper provides a method of consciousness structure analysis for research and development project evaluation using fuzzy structure modeling(FSM). Fuzzy structure modeling, which is a modeling method for consciousness structure, has a large number of pairwise comparison by human subjective judgement and is difficult to check the consistency index of denoting the precision for human judgement. Thus, in this paper, we analyzed the structure of consciousness by fuzzy structural modeling method, introducing the concept of pairwise comparison matrix in Analytic Hierarchy Process.