• 제목/요약/키워드: Deleted Data

검색결과 219건 처리시간 0.022초

디지털 포렌식을 위한 SHA-256 활용 데이터 수정 감지시스템 제안 (A Proposal on Data Modification Detection System using SHA-256 in Digital Forensics)

  • 장은진;신승중
    • 한국인터넷방송통신학회논문지
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    • 제21권4호
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    • pp.9-13
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    • 2021
  • 통신 기술의 발달과 더불어 다양한 형태의 디지털 범죄가 증가하고 있고, 이에 따라 디지털 포렌식에 대한 필요성이 높아지고 있다. 더욱이 특정인이 중요한 데이터를 담고 있는 텍스트 문서를 고의적으로 삭제하거나 수정할 경우 데이터 수정 감지 여부를 확인하는 시스템을 통해 특정인과 범죄와의 연관성을 입증할 수 있는 중요한 자료가 될 수 있을 것이다. 이에 본 논문은 텍스트 파일을 중심으로 암호화 기법 중 하나인 SHA-256의 hash data, 생성 시간, 수정 시간, 접근 시간 및 파일의 크기 등을 분석하여 대상 텍스트 파일의 수정 여부를 비교할 수 있는 데이터 수정 감지 시스템을 제안한다.

학위논문의 목록기술형식 및 검색방법 고찰 (A study of descriptive forms of catalogue and searching method for dissertations)

  • 조호일
    • 한국도서관정보학회지
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    • 제12권
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    • pp.133-160
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    • 1985
  • In college or university libraries, the data of dissertations is one of the important academic information data. But traditional cataloging rules of dissertations and the method of operation is not only didn't unify but also fit to actual circumstances of library. This reason make librarians waste of time and the situation about piling up of unprocessed data don't make library services properly. In this papers, to analyze the above mentioned problems, I have investigated with questionaries about actual examples of construction methods of call number and item describing form of dissertations which is being used now in every college library in Korea. With the replied 61 questionaries which was compared with and investigated to merits and faults about library itself, I have showed revision ways. The characteristics of the revision ways are the followings. 1) Deleted informal and unmeaning descriptions and simplified describing. 2) Recommended to operating one or two kinds describing items which are only necessary. 3) Made call number specifically and then it make us easy to identify data and simultaneously call number can do its original action. 4) shelving range of data is made to colleges, years, departments, majors but in same departments, author's name is recommended by Korean alphabetical ordering. Besides, for proper and systematic management and operating of data. It must be necessary to recommend that reading systems of closed shelves type, incoming and outgoing and shelving by fulltime exclusive charged librarian, separate management of items and data are recommended.

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A study on Customer satisfaction and Repurchase intention on Chinese Mobile service

  • SU, Shuai
    • 한국인공지능학회지
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    • 제7권1호
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    • pp.1-4
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    • 2019
  • This study to investigate Mobile service quality factors influencing on customer satisfaction and repurchase intention for the research purpose. This study collected data by a survey method for an empirical. A total of 340 replies were used for data analysis. While 340 replies were collected from Chinese users of Mobile e-commerce. Our results support previous researches to results of SPSS analysis all of the 7 hypotheses, 4 hypotheses are adopted and 3 are deleted. After an empirical analysis of this study, the academic implications are as follows. As there have not been many academic studies related to mobile commerce quality, this study can be a meaningful framework when quality factors associated with mobile commerce are being analyzed. This paper as the mobile commerce industry is very sensitive to environmental changes, academic research that can be used to cope with these changes is continuously required. Further studies should be carried out to overcome limitations that have not been analyzed by this study.

Object Oriented Design and Implementation of HMI GUI Design Tool

  • Chung Soon Bo;Sun Bok Keun;Han Kwang Rok;Kim Soo Hi
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2004년도 학술대회지
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    • pp.751-754
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    • 2004
  • Nowadays a large number of PLCs are being used in automatic machines for factory automation in industry, and HMI is essential for the effective and convenient operation of PLCs. Each screen displayed in actual EMI equipment should be created, modified and deleted using a PC-based editor and it should be composed of necessary display components to express desired OUI. Based object-oriented development methodology, this study designed screen objects representing a editing screen, display components forming the UI of screens and data management objects necessary for data exchange with HIM system and, based on the objects, implemented a HMI screen editor.

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A File/Directory Reconstruction Method of APFS Filesystem for Digital Forensics

  • Cho, Gyu-Sang;Lim, Sooyeon
    • International Journal of Internet, Broadcasting and Communication
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    • 제14권3호
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    • pp.8-16
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    • 2022
  • In this paper, we propose a method of reconstructing the file system to obtain digital forensics information from the APFS file system when meta information that can know the structure of the file system is deleted due to partial damage to the disk. This method is to reconstruct the tree structure of the file system by only retrieving the B-tree node where file/directory information is stored. This method is not a method of constructing nodes based on structural information such as Container Superblock (NXSB) and Volume Checkpoint Superblock (APSB), and B-tree root and leaf node information. The entire disk cluster is traversed to find scattered B-tree leaf nodes and to gather all the information in the file system to build information. It is a method of reconstructing a tree structure of a file/directory based on refined essential data by removing duplicate data. We demonstrate that the proposed method is valid through the results of applying the proposed method by generating numbers of user files and directories.

인터넷에 올라와 있는 개인정보의 자기결정권과 통제권에 관한 연구 (Study on Decision-making and Control of Personal Data Posted on the Internet)

  • 윤경배
    • 한국인터넷방송통신학회논문지
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    • 제14권4호
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    • pp.227-232
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    • 2014
  • 인터넷 기술이 발전되고, 보편화 되면서 상업과 자본의 대형화가 이루어져 대형 포털 사이트들이 등장하고 성장하게 되면서 인터넷상에서 시간이 흘러도 삭제되지 않는 개인정보 때문에 심각한 사생활 침해문제 등 새로운 위험요소가 제기되고 있다. 특히 마녀사냥 같은 개인의 신상 털기는 피해 당사자가 정상적인 생활이 불가능할 정도의 중대한 문제로 부각되고 있다. 따라서 본 논문에서는 국내외 사례분석을 통하여 개인이 온라인 사이트에 올라와 있는 자신과 관련된 정보 삭제를 요구할 수 있는 권리의 필요성과 국내 도입방안 및 적용에 관한 개선방안을 제안한다.

어분이 $40\%$ 함유된 배합사료에 P, Ca, Zn, Mg, Fe, K, Mn과 Se 무 첨가가 조피볼락의 성장에 미치는 효과 (Effects of Deletion of P, Ca, Zn, Mg, Fe, K, Mn, or Se from Mineral Premix in the Diets Containing $40\%$ Fish Meal on Growth Performance of Juvenile Korean Rockfish (Sebastes schlegeli))

  • 이상민;박승렬;김태진;명정인;장영진
    • 한국수산과학회지
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    • 제31권2호
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    • pp.252-258
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    • 1998
  • 어분이 $40\%$ 첨가된 조피볼락 실용 배합사료의 미네랄 첨가효과와 적정 mineral premix 개발에 필요한 자료를 제공하기 위해 mineral premix중에 P, Ca, Zn, Mg, Fe, K, Mn 및 Se을 각각 첨가하지 않은 실험구와 mineral pre-mix 전부를 첨가하지 않은 실험구를 설정하여 9주간 3 반복으로 사육하였다. 어분 $60\%$ 첨가사료 (HF)와 어분 $40\%$ 첨가사료 (대조구)에 미네랄을 모두 첨가했을 때의 증체율 및 사료효율은 서로 차이가 없었다 (P>0.05). 어분을 $40\%$ 첨가한 사료에 P, Mg, Fe 및 Mn을 각각 첨가하지 않은 사료의 증체율은 미네랄을 모두 첨가한 HF 사료 및 대조사료와 유의차가 없었고 (P>0.05), Ca, Zn, K 및 Se을 각각 첨가하지 않은 사료는 대조구 및 HF사료보다 유의하게 낮았다 (P<0.05). 일일 사료섭취율은 사료간에 유의차는 없었으며, 사료효율은 Zn 무첨가구와 mineral premix를 첨가하지 않은 실험구가 대조구보다 낮은 값 (P<0.05)을 보였으며, 그 외 실험구들은 차이가 없었다. 간의 일반성분 및 중량지수는 사료의 미네랄에 영향을 받지 않았다 (P>0.05). 위의 결과로부터 사료에 어분이 $40\%$ 함유된 사료에는 P, Mg, Fe 및 Mn을 별도로 첨가하지 않아도 될 것으로 판단되며, Ca, Zn, K 및 Se은 별도 첨가가 필요할 것으로 보인다.

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양생측정도구의 타당도와 신뢰도 재검증 -전북지역 노인을 중심으로- (Reassessment of Validity and Reliability of the Tools for Measuring Yangseng -Focused on the Elderly People in Jeonbuk Area-)

  • 정해경;권소희;김애정;왕명자;이기남
    • 대한예방한의학회지
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    • 제9권1호
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    • pp.17-36
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    • 2005
  • The objective of this study is to present basic data for producing tools to measure Yangseng of the elderly aged older than 65 by reassessing the validity and reliability of such tools already developed. In the present study, total 855 subjects were divided into 4 groups and given 31 question for the ultimate factor analysis of each item. The results cloud be summarized as follows: 1. In case of 'don't have sex in drunken state or right after dinner'(the 31st item of sex live yangseng). factor loading came out proportionally in 3 factors such as factor 4=0.358, factor 5=0.389 and factor 6=0.386. As they all failed to reach the general standard of 0.5 or more and even the minimum standard of 0.4 or more, the 31st item was deleted from the questionnaires. 2. From the factor analysis after exclusion of the 31st item, factor loading of the 25th item of sleep yangseng 'go to bed and get up regularly' appeared to be proportional in 2 factor(factor 4=0.393 and factor 7=0.373). Since it was shown that the 25th item could not be classified into a category but interacted with others in common and didn't satisfy the minimum standard of 0.4, it was deleted form the questionnaires, too. 3. From the factor analysis conducted after excluding the item numbers 31 and 25, factor loading of the 12th item of diet yangseng 'do not eat much' turned out to be relatively high with such values as factor 5=0.518 and factor 3=0.453. As it was, however, tied up with the factor of exercise yangseng, it was also deleted. In conclusion, 28 items after excluding the item numbers 12, 25 and 31 form 4 group showed the same results as divided into 8 factor with high grade of reliability and validity, evidencing the assumption that they can be employed practically to measure yangseng of the elderly aged 65 and oder.

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A Query Randomizing Technique for breaking 'Filter Bubble'

  • Joo, Sangdon;Seo, Sukyung;Yoon, Youngmi
    • 한국컴퓨터정보학회논문지
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    • 제22권12호
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    • pp.117-123
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    • 2017
  • The personalized search algorithm is a search system that analyzes the user's IP, cookies, log data, and search history to recommend the desired information. As a result, users are isolated in the information frame recommended by the algorithm. This is called 'Filter bubble' phenomenon. Most of the personalized data can be deleted or changed by the user, but data stored in the service provider's server is difficult to access. This study suggests a way to neutralize personalization by keeping on sending random query words. This is to confuse the data accumulated in the server while performing search activities with words that are not related to the user. We have analyzed the rank change of the URL while conducting the search activity with 500 random query words once using the personalized account as the experimental group. To prove the effect, we set up a new account and set it as a control. We then searched the same set of queries with these two accounts, stored the URL data, and scored the rank variation. The URLs ranked on the upper page are weighted more than the lower-ranked URLs. At the beginning of the experiment, the difference between the scores of the two accounts was insignificant. As experiments continue, the number of random query words accumulated in the server increases and results show meaningful difference.

Skew Detection for Thai Printed Document Images

  • Premchaiswad, Wichian;Duangphasuk, Surakarn
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 ITC-CSCC -1
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    • pp.326-328
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    • 2000
  • The paper proposes the scheme of skew detection for Thai printed document images by using linear regression algorithm. It intends to use with the Thai character recognition systems to reduce the skew detection time. This scheme begins by finding the center of gravity of a document image. This point is used as the starting point for gathering data in the scheme. The data is obtained by scanning incrementally one pixel in vertically with the width of 20-pixels. After the scanning process, if data Is different from it's neighbor more than ${\pm}$ 15 pixels, it will be considered as noise or data in other lines and will be deleted. The last step is the operation by using linear regression algorithm on these selected data and the skew angle will be obtained. The proposed method has been tested with 45 document images with different fonts, sizes and skew angles. The experiment results show that the proposed method can detect the skew angle with the error of less then one degree. The average processing time is about 19 times faster than that of the Hough Transform method.

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