• 제목/요약/키워드: On-line University

검색결과 14,082건 처리시간 0.048초

RSA 문제와 동등한 안전성을 갖는 온라인/오프라인 서명 기법 (On-Line/Off-Line Signature Schemes with Tight Security Reduction to the RSA Problem)

  • 최경용;박종환
    • 정보보호학회논문지
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    • 제28권2호
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    • pp.327-338
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    • 2018
  • 온라인/오프라인(On-line/off-line) 서명은 오프라인 단계에서 서명생성에 필요한 무거운 연산을 수행하고, 온라인 단계에서 간단한 연산만으로 최종 서명을 완성하는 기법이다. 이는 다수의 사용자에게 즉각적인 서명 응답을 해야 하는 응용환경에 적합하다. 본 논문에서는 RSA 문제에 기반한 새로운 온라인/오프라인 서명기법을 두 가지로 제안한다. 첫 번째 기법은 온라인 서명 시 고정된 밑수에서의 지수승이면 되고, 두 번째 기법은 해쉬연산과 같은 매우 간단한 계산만으로 온라인 서명을 완성할 수 있다. 두 서명의 안전성은 모두 RSA 문제로 환원되는데, 랜덤 오라클 모델에서 안전성 손실 없이 증명이 된다.

On-Line Aircraft Parameter Identification Using Fourier Transform Regression With an Application to NASA F/A-18 Harv Flight Data

  • Song, Yongkyu;Song, Byungheum;Seanor, Brad;Napolitano, Marcello R.
    • Journal of Mechanical Science and Technology
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    • 제16권3호
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    • pp.327-337
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    • 2002
  • This paper applies a recently developed on-line parameter identification (PID) technique to sets of real flight data and compares the results with those of a state-of-the-art off-line PID technique. The on-line PID technique takes Linear Regression from Fourier Transformed equations and the off-line PID is based on the traditional Maximum Likelihood method. Sets of flight data from the NASA F/A-18 High Alpha research Vehicle (HARV) circraft, which has been recorded from specifically designed maneuvers and used for our line parameter estimation, are used for this study. The emphasis is given on the accuracy and on-line measure of reliability of the estimates. The comparison is performed for both longitudinal and lateral-directional dynamics for maneuvers at angles of attack ranging u=20°through $\alpha$=40°. Results of the two estimation processes are also compared with baseline wind tunnel estimates whenever possible.

Anatomic Study of Pterygomaxillary Junctions in Koreans

  • Kim, Dong-Yul;Cho, Yeong-Cheol;Sung, Iel-Yong;Yun, Dae-Kawn;Kim, Min-Uk;Kim, Ji-Uk;Son, Hyung-Suck;Son, Jang-Ho
    • Maxillofacial Plastic and Reconstructive Surgery
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    • 제35권6호
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    • pp.368-375
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    • 2013
  • Purpose: This study is to evaluate the location of descending palatine artery, the anatomy of pterygomaxillary junction, and the association between the obtained anatomic values and several variables. Methods: We studied 40 patients who were treated for dentofacial deformites from January 2010 to December 2012 in Ulsan University Hospital, Ulsan, Korea. Cone beam computed tomogram (CBCT) was done for all patients. The reference point was approximately 5 to 7 mm above anterior nasal spine on axial image. We evaluated the location of the greater palatine canal (line a: on the coronal view, the shortest line between the center of greater palatine canal and pterygoid fossa; distance a: the distance of line a). We also measured the thickness (line b: on the coronal view, the shortest line between maxillary posterior sinus wall and pterygoid fossa; distance b: distance of line b), width (line c: on the coronal view, the line perpendicular to the line b and the nearest line from the most concave point of lateral pterygoid plate to the medial pterygoid plate; distance c: distance of line c) and height (line d: on sagittal view, the vertically longest line of pterygoid junction; distance d: the distance of line d) in pterygomaxillary junctions. We evaluated the association between the obtained anatomic values and several variables (sex, age, height and weight). Results: The mean distance a was 4.78 mm, mean distance b was 5.53 mm, mean distance c was 8.01 mm and mean distance d was 13.22 mm. The differences between age and mean distance c and weight and mean distance d in pterygomaxillary junctions are statistically significant. Conclusion: There apparently is anatomic variation of pterygomaxillary junctions by various values, particularly weight and age in a Korean clinical population.

콘텐츠 품질이 학습태도 형성에 미치는 영향에 관한 연구 - 온라인 대학에서 오프강의 병행에 대한 효과- (A study on how the quality of on-line contents influence learning attitudes: Effectiveness of conducting off-line lectures at a Cyber University)

  • 이진희
    • 한국콘텐츠학회:학술대회논문집
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    • 한국콘텐츠학회 2009년도 춘계 종합학술대회 논문집
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    • pp.373-377
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    • 2009
  • 본 연구는 학습자의 효과적 학습을 위해 온라인 상 콘텐츠 품질을 구성하는 요소와 오프 강의가 콘텐츠 품질을 인식하는데 얼마나 영향을 주는가를 알아보기 위한 연구이다. 다속성 태도모델(multiattribute attitude model)의 속성만족도-중요도 모델(attribute satisfaction-importance model)을 중심으로 온라인 학습에 있어 콘텐츠 품질이 학습태도에 미치는 영향과 오프 강의를 병행했을 때의 학습태도(learning attitude) 형성의 변화에 대한 관계를 살펴보고자 한다. 콘텐츠 만족도에 대한 신념(belief)은 콘텐츠 품질을 구성하는 요소로 음성강의, 동영상강의, WBI방식 강의로 나누어 평가한다. 여기에 웹상의 강의와 오프강의를 병행했을 때 형성되는 학습태도의 변화에 대해 연구한다.

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온라인과 오프라인에서 의류 상품 색상감성평가가 상품에 대한 태도에 미치는 영향 -흰색 티셔츠를 중심으로- (Effect of Color Sensibility Evaluation of Clothing Product on Attitude toward Product in On-line and Off-line -Focusing on White T-Shirt-)

  • 여은아
    • 복식문화연구
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    • 제19권3호
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    • pp.650-660
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    • 2011
  • Purpose of this study is to explore: 1) the difference in color sensibility evaluation, color attractiveness, and attitude toward the product, 2) the difference in the effect of color sensibility evaluation on color attractiveness, and 3) the difference in the effect of color sensibility evaluation on attitude toward the product between the identical clothing product presented in on-line and off-line settings. Experimental method was applied with 230 male and female university students using stimuli of an on-line site as well as an off-line window display presenting the same white t-shirts. Color sensibility factors of white t-shirt were hedonic, stimulating, active, and spatial senses. These color sensibility factors of the clothing product affected product color attractiveness as well as attitude toward the product. Although there were not differences in color sensibility evaluation, product attractiveness, and attitude toward the product between items presented in on-line and off-line settings, difference was found in the effect of color sensibility on the color attractiveness and attitude toward the product. The effect of color sensibility on color attractiveness and attitude toward the product was stronger in on-line than in off-line setting. Hedonic sense was the most important factor influencing attractiveness of product color and attitude toward the product. In addition, spatial sense affected attractiveness of product color in on-line setting; and stimulating sense impacted attitude toward the product in off-line setting. Based on the results implications were generated.

Seven-year Survival Rate of On-line Hemodiafiltration

  • Yoon, Jung-Hwan;Kim, Nam-Ho
    • 대한의생명과학회지
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    • 제25권1호
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    • pp.32-39
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    • 2019
  • Conventional high-flux hemodialysis (HD) is not as good as normal kidney function. Morbidity and mortality rates of patients receiving HD are still very high. To increase mid-to-large molecule clearance by combining diffusion and convection, on-line hemodiafiltration (HDF) is required. The objective of this study was to compare long-term survival rate of patients treated with on-line HDF to those who received conventional high-flux HD by reviewing data from Chonnam National University Hospital (CNUH). We selected patients who attended the 'CUNH dialysis center' and agreed to participate in the study. Overall, 40 patients with ESRD switched from high flux HD to on-line HDF or started on-line HDF from August 2007 to December 2009. Additionally, a total of 42 patients receiving conventional high-flux HD during the same period were enrolled. We then reviewed long-term survival rate of patients receiving on-line HDF over the next seven years. When we compared survival rates for seven years, the survival rate of the group receiving on-line HDF was 65% (26/40) while that of the group receiving the conventional high-flux HD was 54.8% (23/42). Although the number of patients was small to see survival difference clearly by one specific dialysis modality, there was somewhat difference in survival rate between the two groups. Indicators such as anemia, calcium-phosphate metabolism, nutritional status, treatment adequacy, and hospitalization were also improved in the group receiving HDF. Overall, results of our study showed beneficial effects of on-line HDF on clinical outcomes and survival in chronic HD patients.

Research on the Correlation of Control Malfunction with Induced Voltage of Control Signal Line According to Voltage Change of a Power Line

  • Kang, Dong-Woo;Kim, In-Gun;Ham, Sang-Hwan;Kim, Sung-Yul;Bae, Sungwoo;Kim, Dae-Nyeon;Lee, Ju
    • Journal of Electrical Engineering and Technology
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    • 제11권3호
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    • pp.775-780
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    • 2016
  • This induced voltage measurement test and electromagnetic field simulation are related to the possibility of control signal malfunction by power line. Through an experiment, this research analyzed whether the voltage causing control malfunction according to the on/off status of power permitted to power line was induced to control signal line. Also, the research calculated the voltage induced to control signal line and examined the phenomenon by conducting an electro-magnetic field-specific simulation through the finite element method for the cable model used in the experiment.

온라인 의류 점포유형에 따른 점포속성 중요도 (The Importance of On-line Store Characteristics Depending on On-line Store Type)

  • 김은숙;김미영
    • 한국의류학회지
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    • 제31권8호
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    • pp.1310-1320
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    • 2007
  • This study investigated the differences in the importance of store characteristics depending on on-line clothing store type and consumer age. The questionnaires were given to female residents in the ages between 20-39 in Seoul and Kyung-gi province during October 2006. The results were summarized as follows: 1. By analyzing the differences in importances of on-line store characteristics factors it was found that buying process service factor and product searching system factor were important in on-line general merchandise store. and buying process service factor and product factor(all the factors, such as store credit, product, screen-displayed design, searching and approaching system, customer management service) were important in on-line specialty store. 2. By analyzing the differences in importances of on-line store characteristics depending on the store type, buying process system such as refund policy, shipping, high-speed payment and rapid searching, screen-displayed design system, approaching and searching system were more important in on-line general merchandise store when comparing to specialty store. It also showed that the consumer considered the reputation of the store and its image more important in on-line general merchandise store. 3. By analyzing the differences in of on-line clothing store importance depending on age, in the case of on-line general merchandise store, it showed that people in their thirties regarded buying process service factor more important than twenties, and when it came to the product and searching system, it was vice versa. Twenties had a tendency to consider the aspect of product important and, relatively, thirties regarded searching and approaching system factor important. in the case of specialty store. It was found that women in their twenties had a tendency to consider product factor more important.

Development of On-line Performance Diagnostic Program of a Helicopter Turboshaft Engine

  • Kong, Chang-Duk;Koo, Young-Ju;Kho, Seong-Hee;Ryu, Hye-Ok
    • International Journal of Aeronautical and Space Sciences
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    • 제10권2호
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    • pp.34-42
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    • 2009
  • Gas turbine performance diagnostics is a method for detecting, isolating and quantifying faults in gas turbine gas path components. On-line precise fault diagnosis can promote greatly reliability and availability of gas turbine in real time operation. This work proposes a GUI-type on-line diagnostic program using SIMULINK and Fuzzy-Neuro algorithms for a helicopter turboshaft engine. During development of the diagnostic program, a look-up table type base performance module are used for reducing computer calculating time and a signal generation module for simulating real time performance data. This program is composed of the on-line condition monitoring program to monitor on-line measuring performance condition, the fuzzy inference system to isolate the faults from measuring data and the neural network to quantify the isolated faults. Evaluation of the proposed on-line diagnostic program is performed through application to the helicopter engine health monitoring.

온라인 게임 캐릭터 복식 색채와 패션 트렌드 색채의 비교 분석 (Comparative Analysis of On-Line Game Characters' Costumes and Fashion Trend Color)

  • 신하나;이민선;유지헌
    • 복식문화연구
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    • 제18권3호
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    • pp.436-451
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    • 2010
  • The purpose of this study is to come up with ways that cooperate between on-line game design and fashion design by analyzing trend color and on-line game character's costume color in on-line game. As for the research methodology, First, on-line games were selected with reference to www.ranky.com. Second, 2009 SS trend color palettes suggested by Copenhagen International Fashion Fair was used as a criterion of fashion trend. Third, on-line game character's costume colors were analyzed in relation to the degree of reflection of trend and the game character's type. The results are as follows. Each on-line game character costume's colors were made in accordance with typical character types. But we can find a one-to-one correspondence between fashion trend colors and game character costume's colors. That's because both trends and character types are the results of the continuing interactions between human-beings and societies. In comparison with fashion trend colors, game character costume colors are partly raw and inharmonious. Therefore, it is necessary to apply fashion trend color in game character costume design for enhancing competitiveness in the world market.