• Title/Summary/Keyword: Computer Assisted

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Efficient Peer-to-Peer File Sharing Using Network Coding in MANET

  • Lee, Uichin;Park, Joon-Sang;Lee, Seung-Hoon;Ro, Won-W.;Pau, Giovanni;Gerla, Mario
    • Journal of Communications and Networks
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    • v.10 no.4
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    • pp.422-429
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    • 2008
  • Mobile peer-to-peer (P2P) systems have recently got in the limelight of the research community that is striving to build efficient and effective mobile content addressable networks. Along this line of research, we propose a new peer-to-peer file sharing protocol suited to mobile ad hoc networks (MANET). The main ingredients of our protocol are network coding and mobility assisted data propagation, i.e., single-hop communication. We argue that network coding in combination with single-hop communication allows P2P file sharing systems in MANET to operate in a more efficient manner and helps the systems to deal with typical MANET issues such as dynamic topology and intermittent connectivity as well as various other issues that have been disregarded in previous MANET P2P researches such as addressing, node/user density, non-cooperativeness, and unreliable channel. Via simulation, we show that our P2P protocol based on network coding and single-hop communication allows shorter file downloading delays compared to an existing MANET P2P protocol.

Exploiting Programmable Shaders in Hardware-Assisted Volume Rendering (PC용 그래픽스 가속기의 쉐이더 기능을 이용한 볼륨 렌더링)

  • Im, In-Seong;Gang, Byeong-Gwon
    • Journal of the Korea Computer Graphics Society
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    • v.8 no.2
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    • pp.23-29
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    • 2002
  • In this paper, we describe an implementation technique that extends the classification and shading capabilities offered by previously reported hardware-assisted volume rendering algorithms. In designing our rendering scheme, we exploited the programmable shader technology supported by the latest consumer PC graphics hardware. Our direct volume rendering technique enables to simultaneously display up to four materials, and to dynamically control gradient magnitude to emphasize or de-emphasize surface boundaries. It can easily create lighting effects such as light source attenuation, depth cueing, and multiple light sources that were often difficult to realize in previous hardware-assisted volume rendering.

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Optoacoustic Ultrasound Generator Based on Nanostructured Germanium (광음향효과를 이용한 게르마늄 나노구조 기반의 초음파 발생 소자 연구)

  • Yoon, Sang-Hyuk;Heo, Junseok
    • Korean Journal of Optics and Photonics
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    • v.26 no.5
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    • pp.255-260
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    • 2015
  • We have fabricated an optoacoustic ultrasound generator based on nanostructured germanium (Ge). Ge thin films were deposited via e-beam evaporation and then etched using a metal-assisted chemical (MAC) method to form nanostructured Ge films. The measured intensity of ultrasound from the nanostructured Ge covered with PDMS was about 3 times stronger than that of 100-nm-thick chromium (Cr). When the nanostructured Ge was embedded in the PDMS, the intensity of ultrasound became 8.5 times as strong compared to the 100-nm-thick Cr.

Modern Treatment of Early Gastric Cancer: Comparison between Laparoscope Assisted vs Hand-Assisted Laparoscopic Distal Gastrectomy vs Open Distal Gastrectomy (조기 위암의 최신 치료 방법 : 복강경 원위부 위절제술, Hand-Assisted 복강경 원위부 위절제술과 소개복 원위부 위절제술의 비교)

  • Yoon, Ki-Young;Gagner, Michel;Lee, Sang-Ho
    • Journal of Gastric Cancer
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    • v.4 no.2
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    • pp.75-81
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    • 2004
  • Recently detection of early gastric cancer (EGC) has been increasing and the treatment strategies for gastric cancer have been changing. The purpose of this study was to compare clinical outcomes between laparoscopically assisted (LADG) and hand-assisted laparoscopic gastrectomy (HALDG) and open distal gastrectomy for early gastric cancer. This review is directed toward providing gastric surgeons with recent advances in the treatment of EGC. We investigated the English language literature for the past 12 years through computer searches which focused on : 1) Patient demographics, 2) Operation time, 3) Intra-operative blood loss, 4) Depth of invasion, 5) CBC, 6)Weight loss, 7) Analgesic requirement, 8)Time NPO, 9) Length of hospital stay, 10) Tumor stage, 11) Lymph node (LN) dissection, 12) Position of LN resected, 13) Complications. Improved operative techniques and surgical instrumentation have facilitated the development of minimally invasive gastric cancer surgery. The short-term benefits of laparoscopic gastrectomy included less surgical trauma, less pain, rapid return of gastrointestinal function, and shorter hospital stay, with no change in operative outcome. Laparoscopic gastrectomy was better accepted by the patients as a good procedure and promptly brought the patients back to their previous lifestyle and activities of daily living. But the advantages of HALDG for gastric cancer, extended lymph node dissection and intracorporeal anastomosis are feasible and easier with the presence of the internal hand. The hand-assisted laparoscopic (HALDG) method reported the best results in lymph node dissection.This method is an alternative to total laparoscopic radical gastrectomy. LADG and HALDG, when compared with conventional open gastrectomy, have several advantages. When performed by a skilled surgeon, LADG and HALDG are safe and useful techniques for patients with early-stage gastric cancer. Their appropriateness for gastric cancer surgery require further study.

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Development of a Computer-Assisted Microbiological Quality Assurance Program for Hosipital Foodservice Operations (병원 급식시설의 미생물적 품질관리를 위한 전산 프로그램개발에 관한 연구)

  • Kwak, Tong-Kyung;Jang, Hye-Ja;Joo, Se-Young
    • Korean journal of food and cookery science
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    • v.8 no.2
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    • pp.137-145
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    • 1992
  • A computer-assisted microbiological quality assurance program was developed based on HACCP data obtained from a 500 bed general hospital by assessing time and temperature conditions and microbiological qualities of six categories of menu items according to the process of food product flow. The purpose of the study was to develop a computer-assisted microbiological quality assurance program in order to simplify the assessment procedures and to provide a maximum assurance to foodservice personnel and the public. A 16-Bit personnel computer compatible with IBM-PC/AT was used. The data base files and processing programs were created using dBASE III plus packages. The contents of the computerized system are summarized as knows: 1. When the input program for hazard analysis runs, a series of questions are asked to determine hazards and assess their severity and risks. Critical control points and monitoring methods for CCPs are identified and saved in Master file. 2. Output and search programs for hazard analysis are composed of 6 categories of recipe data file list, code identification list, and HACCP identification of the specific menu item. 3. When the user selects a specific category of recipe from 6 categories presented on the screen and runs data file list, a series of menu item list, CCP list, monitoring methods list are generated. When the code search program runs, menu names, ingredients, amounts and a series of codes are generated. 4. When the user types in a menu item and an identification code, critical control points and monitoring methods are generated for each menu item.

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Black box-assisted fine-grained hierarchical access control scheme for epidemiological survey data

  • Xueyan Liu;Ruirui Sun;Linpeng Li;Wenjing Li;Tao Liu
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.17 no.9
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    • pp.2550-2572
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    • 2023
  • Epidemiological survey is an important means for the prevention and control of infectious diseases. Due to the particularity of the epidemic survey, 1) epidemiological survey in epidemic prevention and control has a wide range of people involved, a large number of data collected, strong requirements for information disclosure and high timeliness of data processing; 2) the epidemiological survey data need to be disclosed at different institutions and the use of data has different permission requirements. As a result, it easily causes personal privacy disclosure. Therefore, traditional access control technologies are unsuitable for the privacy protection of epidemiological survey data. In view of these situations, we propose a black box-assisted fine-grained hierarchical access control scheme for epidemiological survey data. Firstly, a black box-assisted multi-attribute authority management mechanism without a trusted center is established to avoid authority deception. Meanwhile, the establishment of a master key-free system not only reduces the storage load but also prevents the risk of master key disclosure. Secondly, a sensitivity classification method is proposed according to the confidentiality degree of the institution to which the data belong and the importance of the data properties to set fine-grained access permission. Thirdly, a hierarchical authorization algorithm combined with data sensitivity and hierarchical attribute-based encryption (ABE) technology is proposed to achieve hierarchical access control of epidemiological survey data. Efficiency analysis and experiments show that the scheme meets the security requirements of privacy protection and key management in epidemiological survey.

A Practical Digital Video Database based on Language and Image Analysis

  • Liang, Yiqing
    • Proceedings of the Korea Database Society Conference
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    • 1997.10a
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    • pp.24-48
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    • 1997
  • . Supported byㆍDARPA′s image Understanding (IU) program under "Video Retrieval Based on Language and image Analysis" project.DARPA′s Computer Assisted Education and Training Initiative program (CAETI)ㆍObjective: Develop practical systems for automatic understanding and indexing of video sequences using both audio and video tracks(omitted)

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An Implementation of an Courseware Authoring Tool Using a Concept based Courseware Representation Method (개념 기반의 코스웨어 표현 방법과 이를 이용한 인터넷 기반의 코스웨어 저작 도구의 구현)

  • Kim, Man-Seok;Kim, Chang-Hwa
    • The Journal of Korean Association of Computer Education
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    • v.5 no.2
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    • pp.39-48
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    • 2002
  • It is general that the ICAI(Intelligent Computer Assisted Instruction) consists of 4 modules. Export module, Teacher module, Student module and Interface module. In each module construction, there should be some rules to control strategies efficiently and systematically that are related to the texts and assessment instruments, assessment results and evaluation, feedback, etc. It is necessary to use a method to classify the curriculum into sections with units and to represent the identified relationships between them. These relationships are available to all the process of learning, assessment, evaluation and feedback. In this paper, we propose the method to represent these units and relationships as a graph. In addition, we implement an internet-based courseware authoring tool to support the environment in which several expert can construct concurrently the courseware with cooperation between them.

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