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A countermeasure against Foreshadow and ZombieLoad attacks based on segmentation fault monitoring (Segmentation fault 모니터링을 통한 Foreshadow 및 ZombieLoad 공격 방어 기법 연구)

  • Lee, Jun-Yeon;Suh, Taeweon
    • Proceedings of the Korea Information Processing Society Conference
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    • 2019.10a
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    • pp.384-387
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    • 2019
  • 2018년 Meltdown 공격이 발표된 이후 Foreshadow, ZombieLoad 등 다양한 종류의 마이크로아키텍처 기반 부 채널 공격과 방어 기법들이 발표되었다. 그중 Meltdown 공격을 원천 차단할 수 있는 KPTI (Kernel Page Table Isolation)는 커널 영역을 사용자 메모리 영역과 분리하여 커널 정보의 유출을 방어할 수 있으나, 최대 46%의 시스템 성능 저하를 가져온다. 본 연구는 런타임에 시스템콜 발생빈도를 분석하여 낮은 오버헤드로 Meltdown-type 공격을 탐지하고, 방어하는 프로그램을 개발하고 실험하였다. 개발한 Fault Monitoring Tool은 기존 시스템 대비 적은 오버헤드(최대 7%)로 악의적인 사용자를 구분해 내고 방어할 수 있었다.

A Table Parametric Method for Automatic Generation of Parametric CAD Models in a Mold Base e-Catalog System (몰드베이스 전자 카탈로그 시스템의 파라메트릭 CAD 모델 자동 생성을 위한 테이블 파라메트릭 방법)

  • Mun, Du-Hwan;Kim, Heung-Ki;Jang, Kwang-Sub;Cho, Jun-Myun;Kim, Jun-Hwan;Han, Soon-Hung
    • The Journal of Society for e-Business Studies
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    • v.9 no.4
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    • pp.117-136
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    • 2004
  • As the time-to-market gets more important for competitiveness of an enterprise in manufacturing industry, it becomes important to shorten the development cycle of a product. Reuse of existing design models and e-Catalog for components are required for faster product development. To achieve this goal, an electric catalog must provide parametric CAD models since parametric information is indispensable for configuration design. There are difficulties in building up a parametric library of all the necessary combination using a CAD system, since we have too many combinations of components for a product. For example, there are at least 80 million combinations of components on one page of paper catalog of a mold base. To solve this problem, we propose the method of table parametric for the automatic generation of parametric CAD models. Any combination of mold base can be generated by mapping between a classification system of an electric catalog and the design parameters set of the table parametric. We propose how to select parametric models and to construct the design parameters set.

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A Development of Fusion Processor Architecture for Efficient Main Memory Access in CPU-GPU Environment (CPU-GPU환경에서 효율적인 메인메모리 접근을 위한 융합 프로세서 구조 개발)

  • Park, Hyun-Moon;Kwon, Jin-San;Hwang, Tae-Ho;Kim, Dong-Sun
    • The Journal of the Korea institute of electronic communication sciences
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    • v.11 no.2
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    • pp.151-158
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    • 2016
  • The HSA resolves an old problem with existing CPU and GPU architectures by allowing both units to directly access each other's memory pools via unified virtual memory. In a physically realized system, however, frequent data exchanges between CPU and GPU for a virtual memory block result bottlenecks and coherence request overheads. In this paper, we propose Fusion Processor Architecture for efficient access of main memory from both CPU and GPU. It consists of Job Manager, Re-mapper, and Pre-fetcher to control, organize, and distribute work loads and working areas for GPU cores. These components help on reducing memory exchanges between the two processors and improving overall efficiency by eliminating faulty page table requests. To verify proposed algorithm architectures, we develop an emulator based on QEMU, and compare several architectures such as CUDA(Compute Unified Device Architecture), OpenMP, OpenCL. As a result, Proposed fusion processor architectures show 198% faster than others by removing unnecessary memory copies and cache-miss overheads.

A Study on Comparison of 6th Curriculum and 7th Curriculum of Home Economics Textbooks in the Middle School (제 6차와 7차 교육과정에 따른 중학교 가정 교과서 비교 연구)

  • Yoon In Kyung
    • Journal of Korean Home Economics Education Association
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    • v.16 no.4 s.34
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    • pp.1-8
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    • 2004
  • The purpose of this study was to investigate as to how much of changes has occurred in the newly revised Home Economics Textbooks required by the 7th Curriculum as compared to those by the former 6th Curriculum. and to seek future policy direction which can be improved even better. if any. for further revision. To implement this proposal, this study employed 8 different textbooks published among 12 textbooks developed for the 7th Curriculum for data base. The results of this study were as follows: It was covered such areas of change and develope in the composition of category and system in the Home Economics Textbooks required by the 7th Curriculum as compared to those by the former 6th Curriculum. The whole system of textbook was composed of cover page, the inside of a book cover. the title page, introduction. table of contents. appendices. It was same in the total pages with the exception of table of contents. appendices. the inside of a book cover and it was much alike in contents of introduction. In the aspect of the unit system of the textbooks. their whole flows were similar to each other. but the writers' intention and the stress on the focal points had appeared well in topic introduction and texts for the units of the textbooks. In addition. it can be said desirable that much more middle school teachers took a participation in the development of textbooks as textbook writers than before. In the organizational aspect of the sub-area organization of textbooks in the 7th Curriculum, it was not dispersed in grade 1, 2, and 3, but was centralized in a certain grade to increase its efficiency. The number of activity and experiment & practice that students could try to do actually were drastically increased compared to the 6th Curriculum. but it showed a wide difference between textbooks.

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A Study on Jo Bok-seong's Insect-related Books Published in 1948: Focused on Story of Insects and About Insects (1948년에 출간된 조복성의 곤충 관련 저작에 관한 연구 - 『곤충이야기』와 『곤충기』를 중심으로 -)

  • Jin, Na-Young
    • Journal of the Korean Society for Library and Information Science
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    • v.53 no.2
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    • pp.267-294
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    • 2019
  • This study conducted analysis on forms and contents of Story of Insects (Gonchung Iyagi) and About Insects (Gonchung-gi), writings of biologist Jo Bok-seong published in 1948 to examine characteristics of two books and compare them. Story of Insects was made in the form of front cover-title page-foreword-table of contents-main text-copyright clause-advertisement-back cover, with the book size being A5 format. Contents of the book were divided into nine groups according to the characteristics of 65 species insects, to describe their characteristics. While, About Insects was made in the form of cover-title page-foreword-table of contents-main text-copyright clause-publication message of Eulyoo Mungo-advertisement-back cover, with the book size of A6 format. Contents of the book were divided into the author's own 11 groups according to the characteristics of 56 species insects, to describe their characteristics. About Insects being Eulyoo Publishing Co. and Story of Insects being Association of Joseon Children's Culture (abbreviated as Ahyeop) - sister company of Eulyoo Publishing Co. - but with the same basis.

Document Image Segmentation and Classification using Texture Features and Structural Information (텍스쳐 특징과 구조적인 정보를 이용한 문서 영상의 분할 및 분류)

  • Park, Kun-Hye;Kim, Bo-Ram;Kim, Wook-Hyun
    • Journal of the Institute of Convergence Signal Processing
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    • v.11 no.3
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    • pp.215-220
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    • 2010
  • In this paper, we propose a new texture-based page segmentation and classification method in which table region, background region, image region and text region in a given document image are automatically identified. The proposed method for document images consists of two stages, document segmentation and contents classification. In the first stage, we segment the document image, and then, we classify contents of document in the second stage. The proposed classification method is based on a texture analysis. Each contents in the document are considered as regions with different textures. Thus the problem of classification contents of document can be posed as a texture segmentation and analysis problem. Two-dimensional Gabor filters are used to extract texture features for each of these regions. Our method does not assume any a priori knowledge about content or language of the document. As we can see experiment results, our method gives good performance in document segmentation and contents classification. The proposed system is expected to apply such as multimedia data searching, real-time image processing.

The Assesment of the Internet Information on Provincial Cultural Festivals -Based on the "Cultural Festivals of Korea 2001" Designated by the Ministry of Culture and Tourism- (지방문화축제에 관한 인터넷정보의 평가 -2001년 문화관광부지정 문화축제를 중심으로-)

  • 이시영;심준영
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.2
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    • pp.85-94
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    • 2001
  • The study aims at assessing information on cultural festivals furnished through the internet homepage of a provincial government. The study examines 29 tourist festivals of ˝Cultural Festivals of Korea 2001˝, designated by the Ministry of Culture and Tournism. Based on the inquiring table, framed through the previous study, each festival´s information was surveyed and analyzed, by visiting the homepages of provincial governments. The results of the study show that 1) ˝The information of festival˝ is low in quality. Particularly, ˝the contents of festival˝ needs to be improved and expanded and ˝the festival periods˝ should be brought up to date. These are the important factors in making a decision to participate in the festival and the chief attraction of a homepage, well-planned and detailed information can influence more tourists who are interested in visiting a festival. 2) Seventeen festivals support ˝foreign language˝. But ˝festival information˝ is weak as it provides only an outline of festival and doesn´t even contain the date and contents of festival. Valuable information, like transportations, accommodations and restaurants when tourists visit a tourist spot, and detailed festival contents should be provided. 3) ˝Search˝ and ˝Q and A˝ are function which provide specifics for users. In addition to the homepage of a local government, these functions on the web page of cultural festivals or on an exclusive web page of tourism is required. 4) The homepage of festivals should offer ˝the information of participation˝. The convenience of information searchers should be considered by providing them information such as local prices, transportations, accommodations and restaurants which are necessary to participate in festival.

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A Study on the Gongjungwisaeng Kanhohak, the First Korean Textbook for Public Health Nursing (우리나라 최초의 보건간호학 교과서 "공중위생간호학" 연구)

  • June, Kyung Ja;Yi, Ggodme
    • Research in Community and Public Health Nursing
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    • v.33 no.1
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    • pp.84-95
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    • 2022
  • Purpose: The purpose of this study is to extend the knowledge about the textbook, Public Health Nursing Textbook (in Korean, Gongjungwisaeng Kanhohak) which is published in 1933 by the Nurses' Association of Korea. Methods: Public Health Nursing Textbook was investigated from the cover page to the last page and compared with two original books and other nursing books published in modern Korea. Results: Public Health Nursing Textbook was the forth published Korean nursing textbook and the first published Korean public health nursing textbook. Rosenberger, a missionary nurse from USA, Lee Keumjeon, Korean public health nurse who studied in Canada, and other Koreans were in charge of translation, etc. It is a user - friendly book written mainly in Korean (Hangul) with Chinese characters and included the English table of contents, preface and back cover. Most of its contents were extracted and translated from two original books, one is Public Health Nursing by Mary Gardner and the other is Personal Hygiene Applied by Jesse Williams. It is worth noting that the book not only introduced the public health nurses's activities across the country, but also focused on the information necessary for common health problems at that time. Conclusion: From the Public Hygiene and Nursing, it can be seen that public health nurses had been independently educated since Imperial Japan's colonial period, and public health nursing was growing as a independent field in Korea.

A PageRank based Data Indexing Method for Designing Natural Language Interface to CRM Databases (분석 CRM 실무자의 자연어 질의 처리를 위한 기업 데이터베이스 구성요소 인덱싱 방법론)

  • Park, Sung-Hyuk;Hwang, Kyeong-Seo;Lee, Dong-Won
    • CRM연구
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    • v.2 no.2
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    • pp.53-70
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    • 2009
  • Understanding consumer behavior based on the analysis of the customer data is one essential part of analytic CRM. To do this, the analytic skills for data extraction and data processing are required to users. As a user has various kinds of questions for the consumer data analysis, the user should use database language such as SQL. However, for the firm's user, to generate SQL statements is not easy because the accuracy of the query result is hugely influenced by the knowledge of work-site operation and the firm's database. This paper proposes a natural language based database search framework finding relevant database elements. Specifically, we describe how our TableRank method can understand the user's natural query language and provide proper relations and attributes of data records to the user. Through several experiments, it is supported that the TableRank provides accurate database elements related to the user's natural query. We also show that the close distance among relations in the database represents the high data connectivity which guarantees matching with a search query from a user.

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Block Unit Mapping Technique of NAND Flash Memory Using Variable Offset

  • Lee, Seung-Woo;Ryu, Kwan-Woo
    • Journal of the Korea Society of Computer and Information
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    • v.24 no.8
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    • pp.9-17
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    • 2019
  • In this paper, we propose a block mapping technique applicable to NAND flash memory. In order to use the NAND flash memory with the operating system and the file system developed on the basis of the hard disk which is mainly used in the general PC field, it is necessary to use the system software known as the FTL (Flash Translation Layer). FTL overcomes the disadvantage of not being able to overwrite data by using the address mapping table and solves the additional features caused by the physical structure of NAND flash memory. In this paper, we propose a new mapping method based on the block mapping method for efficient use of the NAND flash memory. In the case of the proposed technique, the data modification operation is processed by using a blank page in the existing block without using an additional block for the data modification operation, thereby minimizing the block unit deletion operation in the merging operation. Also, the frequency of occurrence of the sequential write request and random write request Accordingly, by optimally adjusting the ratio of pages for recording data in a block and pages for recording data requested for modification, it is possible to optimize sequential writing and random writing by maximizing the utilization of pages in a block.