• Title/Summary/Keyword: 공개영역

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A Robust Watermarking Method against Partial Damage and Geometric Attack (부분 손상과 기하학적 공격에 강인한 워터마킹 방법)

  • Kim, Hak-Soo
    • Journal of Korea Multimedia Society
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    • v.15 no.9
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    • pp.1102-1111
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    • 2012
  • In this paper, we propose a robust watermarking method against geometric attack even though the watermarked image is partially damaged. This method consists of standard image normalization which transforms any image into a predefined standard image and embedding watermark in DCT domain of standard normalized image using spread spectrum technique. The proposed standard image normalization method has an improvement over existing image normalization method, so it is robust to partial damage and geometric attack. The watermark embedding method using spread spectrum technique also has a robustness to image losses such as blurring, sharpening and compressions. In addition, the proposed watermarking method does not need an original image to detect watermark, so it is useful to public watermarking applications. Several experimental results show that the proposed watermarking method is robust to partial damage and various attacks including geometric deformation.

Facial Expression Recognition with Instance-based Learning Based on Regional-Variation Characteristics Using Models-based Feature Extraction (모델기반 특징추출을 이용한 지역변화 특성에 따른 개체기반 표정인식)

  • Park, Mi-Ae;Ko, Jae-Pil
    • Journal of Korea Multimedia Society
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    • v.9 no.11
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    • pp.1465-1473
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    • 2006
  • In this paper, we present an approach for facial expression recognition using Active Shape Models(ASM) and a state-based model in image sequences. Given an image frame, we use ASM to obtain the shape parameter vector of the model while we locate facial feature points. Then, we can obtain the shape parameter vector set for all the frames of an image sequence. This vector set is converted into a state vector which is one of the three states by the state-based model. In the classification step, we use the k-NN with the proposed similarity measure that is motivated on the observation that the variation-regions of an expression sequence are different from those of other expression sequences. In the experiment with the public database KCFD, we demonstrate that the proposed measure slightly outperforms the binary measure in which the recognition performance of the k-NN with the proposed measure and the existing binary measure show 89.1% and 86.2% respectively when k is 1.

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Implementation and Evaluation of IoT Service System for Security Enhancement (보안성 향상을 위한 IoT 서비스 시스템 구현 및 평가)

  • Kim, Jin-bo;Kim, Mi-sun;Seo, Jae-hyun
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.27 no.2
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    • pp.181-192
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    • 2017
  • Internet of Things includes the whole process of collected information generated from a variety of objects, as well as analyzing and sharing it, and providing useful information services to people. This study seeks ways to improve security and safety in the areas of service security technology, ID management technology and service access control, all of which take place in the IoT environment. We have implemented the services that can design and issue C&C (Certificate and Capability) service token authentication, which is based on a public key, to improve the service security. In addition, we suggest LCRS (Left Child-Right Sibling) resource model management for the efficient control of resources when generating the resource services from the data collected from node devices. We also implemented an IoT services platform to manage URL security of the resource services and perform access control for services.

A Study on the Improvement Method of Deleted Record Recovery in MySQL InnoDB (MySQL InnoDB의 삭제된 레코드 복구 기법 개선방안에 관한 연구)

  • Jung, Sung Kyun;Jang, Jee Won;Jeoung, Doo Won;Lee, Sang Jin
    • KIPS Transactions on Computer and Communication Systems
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    • v.6 no.12
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    • pp.487-496
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    • 2017
  • In MySQL InnoDB, there are two ways of storing data. One is to create a separate tablespace for each table and store it separately. Another is to store all table and index information in a single system tablespace. You can use this information to recover deleted data from the record. However, in most of the current database forensic studies, the former is actively researched and its structure is analyzed, whereas the latter is not enough to be used for forensics. Both approaches must be analyzed in terms of database forensics because their storage structures are different from each other. In this paper, we propose a method for recovering deleted records in a method of storing records in IBDATA file, which is a single system tablespace. First, we analyze the IBDATA file to reveal its structure. And introduce delete record recovery algorithm which extended to an unallocated page area which was not considered in the past. In addition, we show that the recovery rate is improved up to 68% compared with the existing method through verification using real data by implementing the algorithm as a tool.

Efficient dummy generation for protecting location privacy in location based services (위치기반 서비스에서 위치 프라이버시를 보호하기 위한 효율적인 더미 생성)

  • Cai, Tian-yuan;Youn, Ji-hye;Song, Doo-hee;Park, Kwang-jin
    • Journal of Internet Computing and Services
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    • v.18 no.5
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    • pp.23-30
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    • 2017
  • For enjoying the convenience provided by location based services, the user needs to submit his or her location and query to the LBS server. So there is a probability that the untrusted LBS server may expose the user's id and location etc. To protect user's privacy so many approaches have been proposed in the literature. Recently, the approaches about using dummy are getting popular. However, there are a number of things to consider if we want to generate a dummy. For example, when generating a dummy, we have to take the obstacle and the distance between dummies into account so that we can improve the privacy level. Thus, in this paper we proposed an efficient dummy generation algorithm to achieve k-anonymity and protect user's privacy in LBS. Evaluation results show that the algorithm can significantly improve the privacy level when it was compared with others.

The Communication of Elementary Math Classes Through Observing the Excellent Lesson Videos (우수수업 사례를 통해서 본 초등 수학 교실에서의 의사소통)

  • Choi, Eun-Ah;Lee, Kwang-Ho
    • School Mathematics
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    • v.12 no.4
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    • pp.507-530
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    • 2010
  • The purpose of this study was to help teachers for their teaching practice by analyzing the excellent lesson videos. To analyze the lesson videos between teacher and students, the researchers classified excellent lesson classes into four types as 'Discourse type', 'Representation type', 'Operation type' and 'Complex type' by mathematical communication pattern and kept close watch each lesson videos. Mathematical communication of the best discourse type classroom was analyzed in terms of questioning, explaining, and the sources of mathematical ideas. As a result, the number of Discourse type classes was 6. Operation type classes were 16 owing to characteristic of elementary class. Representation type class was 1 and Complex type class was 1. The Classes excluding Operation type was more planned by teachers. Teachers need to know about mathematical communication accurately because they designed just 5 lesson plan considering mathematical communication of students and only one of the lessons has the intellectual purpose of communication. Furthermore teachers should reflect questioning for student-to-student in their lesson plan.

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Development and Effectiveness of Counseling Manual for Community-based Visiting Nursing (맞춤형 방문건강관리사업 상담매뉴얼 개발과 효과)

  • Choi, Kyung-Won;Lim, Ji-Young;Kim, Eun-Joo
    • The Journal of the Korea Contents Association
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    • v.12 no.9
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    • pp.226-233
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    • 2012
  • Purpose: The purpose of this study was to develop and analyze the effectiveness of an education program counseling manual (EPCM) for community-based visiting nurses. Methods: Seventy-eight of community-based visiting nurses was enrolled in this study. Data were collected using structured questionnaires and analyzed using descriptive statistics, the ${\chi}^2$-test, and the paired t-test in SPSS version 18.0. Results: Nurses had higher mean scores for counselor activity self-efficacy: skill self-efficacy, session management self-efficacy and counseling challenges self-efficacy, after EPCM than before EPCM. Significant differences were found after applying the EPCM. Conclusion: The results of this study indicate that the EPCM is effective at improving counselor self-efficacy of community-based visiting nurses.

A Design and Implementation of Mobile E-mail Transmission System Using PC Remote Control Technique (PC 원격 제어 기법을 사용한 모바일 이메일 전송 시스템 설계 및 구현)

  • Song, Hye-Ju;Kim, Hyun-Ju;You, Hyun-Jung;Lee, Jong-Woo
    • Journal of Digital Contents Society
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    • v.8 no.1
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    • pp.17-25
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    • 2007
  • Recently, the ubiquitous computing environment being able to connect all kinds of computing elements at anytime anywhere becomes widespread in human life. In this paper, we focus on a PC remote control system using cellular phones. Especially, we design and implement an mobile e-mail transmission system using PC remote control technique. By using our remote controller, cellular phone users can login into their own PC, and then send any file to others by e-mail attachment. To show the correct running of our system, real demonstration results are presented. We are sure that by opening our source code to the public our results can play an important role to encourage development of the various mobile remote control functionalities.

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A New Natural Convection Heat Transfer Correlation for Laminar and Turbulent Film Condensation Derived from a Statistical Analysis of Existing Models and Data (기존모델과 실험자료의 통계적 분석에 의해 유도한 층류 및 난류 막응축에 대한 새로운 자연대류 열전달 관계식)

  • Chun, Moon-Hyun;Kim, Kyun-Tae
    • Nuclear Engineering and Technology
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    • v.23 no.2
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    • pp.200-209
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    • 1991
  • A new semi-empirical average heat transfer correlation applicable for both laminar and turbulent film-wise condensation on a vertical surface has been presented. Re functional form of the present correlation is based on the representative existing correlations for laminar and turbulent film flows, whereas the numerical coefficients of the present correlation have been determined by the least squares method using experimental data obtained from the open literatures. In addition, the performance of the present as well as the seven existing correlations (four for laminar and three for turbulent film flow regimes) were evaluated for their accuracy and the range of application. The result shows that for laminar film filow regimes Zazuli's and the present correlations give the samllest values of mean error, whereas for turbulent film How regimes Kirkbride and Badger's and the present correlations produce the smallest values of mean error.

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Well-Structured Inter-Oranizational Workflow Modeling for B2B e-Commerce

  • Li, Xizuo;Kim, Sun-Ho
    • The Journal of Society for e-Business Studies
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    • v.9 no.4
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    • pp.53-64
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    • 2004
  • Today's enterprises take processes beyond their own organizational boundaries in order to electronically trade goods and services with partners under the concept of B2B e-commerce. In this environment, inter-organizational business processes are required and should be well defined not only in public processes between partners but in private processes within individual partners. For this purpose, we propose the method to represent inter-organizational business processes. First of all, a feasible modeling method for the inter-organizational workflow for B2B e-commerce is developed. This method is proposed based on BPSS in ebXML so that the binary and multiparty collaborations share a common process. In this method, message flows and control flows are separated in order to facilitate the design procedure of the inter-organizational workflow process. Second, a well-structured process modeling algorithm to design a well-structured inter-organizational workflow process is proposed. In the algorithm, a process is transformed to a Petri-net-based process model. This algorithm employs well-behaved modeling blocks, well-behaved control structures, and business transactions to develop well-structured process models by a top-down design.

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