• Title/Summary/Keyword: Similarity Measurement

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The Effect of Perceived Risks and Performance regarding Psychic Distance (심리적거리가 지각된 위험과 성과에 미치는 영향)

  • Hwang, Hwa-cheol
    • Journal of Distribution Science
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    • v.7 no.2
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    • pp.63-87
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    • 2009
  • The conclusions shown by this study are as follows: Firstly, Despite the similarity of the objective distance caused by the geographic distance and cultural similarities. it is found that the psychic distance factor still exists. Secondly, a new affective factor of psychic distance has been noted. As to the shaping method, even though culture and psychic distance involve homeogenic factors, psychic distance is more complex in that it is affected not only by cultural changes but also by other affective factors. Culture is a very significant factor, which can have an effect on forming psychic distance, but it is short of being a measurement variable for measuring psychic distance. Thirdly, psychic distance can have a direct effect on customers' buying response. If it is just a belief shared among the people of a nation, it can't become an important notion.

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A Study on Image Evaluation System based on Prototype Theory (프로토타입 이론을 적용한 계층적 이미지 계측시스템)

  • 김돈한
    • Archives of design research
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    • v.14 no.1
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    • pp.27-34
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    • 2001
  • In order to design the products that impression or emotional taste influence the purchase, feedback is necessary as useful data for better idea sketches through users emotional evaluation in early stage of design process. On the other hand, it was required to make judgments individually in previous image evaluations for emotional evaluations such as semantic differential method (SD method) that objects have been considered as classified tendency. However those SD methods are not enough to reflect flexible human capability with similarity judgment in object perceptual process. Therefore, this study proposes a classification of stimulus based on intuitive judgment and a hierarchical image evaluation method based on analysis of hierarchical process and fuzzy integration. The evaluation will be conducted through the order of process, intuitive classification of objective stimulus and items, definition of representatives in each class. Evaluation for each image of the stimulus, calculation of prior raking based on fuzzy integration. The evaluation supportive software is developed to conduct this evaluation process under interactive environments.

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A Study of SPA Vulnerability on 8-bit Implementation of Ring-LWE Cryptosystem (8 비트 구현 Ring-LWE 암호시스템의 SPA 취약점 연구)

  • Park, Aesun;Won, Yoo-Seung;Han, Dong-Guk
    • Journal of the Korea Institute of Information Security & Cryptology
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    • v.27 no.3
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    • pp.439-448
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    • 2017
  • It is news from nowhere that post-quantum cryptography has side-channel analysis vulnerability. Side-channel analysis attack method and countermeasures for code-based McEliece cryptosystem and lattice-based NTRU cryptosystem have been investigated. Unfortunately, the investigation of the ring-LWE cryptosystem in terms of side-channel analysis is as yet insufficient. In this paper, we propose a chosen ciphertext simple power analysis attack that can be applied when ring-LWE cryptography operates on 8-bit devices. Our proposed attack can recover the key only with [$log_2q$] traces. q is a parameter related to the security level. It is used 7681 and 12289 to match the common 128 and 256-bit security levels, respectively. We identify the vulnerability through experiment that can reveal the secret key in modular add while the ring-LWE decryption performed on real 8-bit devices. We also discuss the attack that uses a similarity measurement method for two vectors to reduce attack time.

Development of Ultrasonic Sensor to Measure the Distance in Underwater (수중 거리 측정을 위한 초음파 센서의 개발)

  • Kim, Chi-Hyo;Kim, Tae-Sung;Jung, Jun-Ha;Lee, Jin-Hyung;Lee, Min-Ki;Jang, In-Sung;Shin, Chang-Joo
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2013.06a
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    • pp.293-298
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    • 2013
  • This research develops an ultrasonic sensor to measure the distance in underwater. The ultrasonic transducer transmits an acoustic signal to an object and receives the echo signal reflected from the object. The ultrasonic driver calculates a distance by multiplying the acoustic speed to the time of flight(TOF) which is the time necessary for the acoustic signal to travel from the transducer to the object. We apply a thresholding and a cross correlation methods to detect the TOF and show their results. When an echo pulse is corrupted with noise and its shape is distorted, the cross correlation method is used to find the TOF based on the maximum similarity between the reference and the delayed echo signals. The echoes used for the reference signal are achieved at the different environments, which improves the performance of the sensor. This paper describes the driver of the acoustic sensor and analyzes the performance of sensors in different measurement environments.

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Implementation of a Chatbot Application for Restaurant recommendation using Statistical Word Comparison Method (통계적 단어 대조를 이용한 음식점 추천 챗봇 애플리케이션 구현)

  • Min, Dong-Hee;Lee, Woo-Beom
    • Journal of the Institute of Convergence Signal Processing
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    • v.20 no.1
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    • pp.31-36
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    • 2019
  • A chatbot is an important area of mobile service, which understands informal data of a user as a conversational form and provides a customized service information for user. However, there is still a lack of a service way to fully understand the user's natural language typed query dialogue. Therefore, in this paper, we extract meaningful words, such a region, a food category, and a restaurant name from user's dialogue sentences for recommending a restaurant. and by comparing the extracted words against the contents of the knowledge database that is built from the hashtag for recommending a restaurant in SNS, and provides user target information having statistically much the word-similarity. In order to evaluate the performance of the restaurant recommendation chatbot system implemented in this paper, we measured the accessibility of various user query information by constructing a web-based mobile environment. As a results by comparing a previous similar system, our chabot is reduced by 37.2% and 73.3% with respect to the touch-count and the cutaway-count respectively.

An intelligent hybrid methodology of on-line system-level fault diagnosis for nuclear power plant

  • Peng, Min-jun;Wang, Hang;Chen, Shan-shan;Xia, Geng-lei;Liu, Yong-kuo;Yang, Xu;Ayodeji, Abiodun
    • Nuclear Engineering and Technology
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    • v.50 no.3
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    • pp.396-410
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    • 2018
  • To assist operators to properly assess the current situation of the plant, accurate fault diagnosis methodology should be available and used. A reliable fault diagnosis method is beneficial for the safety of nuclear power plants. The major idea proposed in this work is integrating the merits of different fault diagnosis methodologies to offset their obvious disadvantages and enhance the accuracy and credibility of on-line fault diagnosis. This methodology uses the principle component analysis-based model and multi-flow model to diagnose fault type. To ensure the accuracy of results from the multi-flow model, a mechanical simulation model is implemented to do the quantitative calculation. More significantly, mechanism simulation is implemented to provide training data with fault signatures. Furthermore, one of the distance formulas in similarity measurement-Mahalanobis distance-is applied for on-line failure degree evaluation. The performance of this methodology was evaluated by applying it to the reactor coolant system of a pressurized water reactor. The results of simulation analysis show the effectiveness and accuracy of this methodology, leading to better confidence of it being integrated as a part of the computerized operator support system to assist operators in decision-making.

Comparison of Daily Soil Water Contents between Energy BalanceWater Budget Approach and TDR (에너지와 물수지 연계방법과 TDR로부터 얻어진 매일 토양 함수량의 비교)

  • 임창수
    • Water for future
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    • v.29 no.4
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    • pp.119-129
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    • 1996
  • The daily soil water contents were obtained from the time domain reflectometry (TDR) method and energy balance-water budget approach with eddy correlation at the two small semiarid watersheds of Lucky Hills and Kendall during the summer rainy period. There was a comparison of daily soil water content measured and estimated from these two different approaches. The comparison is valuable to evaluate the accuracy of current soil water content measuring system using TDR and energy balance-water budget approach using eddy correlation method at small watersheed scale. The degree of similarity between the regressions of these two methods of measuring soil water content was explained by determining the correlations between these methods. Simple linear regression analyses showed that soil water content measured from TDR method was responsible for 58% and 63% of the variations estimated from energy balance-water budget approach with eddy correlation at Lucky Hills and Kendall, respectively. The scatter plots and the regression analyses revealed that two different approaches for soil water content measurement at small watershed scale have no significant difference.

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Comprehensive Review of Standard Occupational Classification (SOC) as used in the Occupational Safety and Health Field (산업안전보건분야에서 표준직업분류(Standard Occupational Classification, SOC) 활용 사례 고찰 및 향후 국내 도입 방안 제언)

  • Park, Donguk;Choi, Sangjun;Byun, Hyaejeong;Kim, Yangho;Kim, Soogeon;Ha, Kwonchul;Kang, Taesun
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.23 no.1
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    • pp.11-19
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    • 2013
  • Backgrounds: Occupations are grouped on the basis of similarity in tasks and duties performed. Standard occupational classification (SOC) is a tool for organizing all professions into a clearly defined set of groups according to the tasks and duties undertaken in the respective jobs. Objectives: The major objective of this study is to comprehensively review how a SOC system is used in occupational and safety fields such as surveillance, exposure monitoring, occupational epidemiological study, management of carcinogens and analysis of occupational accidents. Methods: We summarized the cases, policies and regulations used in SOC systems in advanced countries and as they appear in articles Results: We found that SOC systems have been widely used in various areas of occupational safety and health in the US, the UK, Finland, and the EU. In general, it is highly common to use SOC in the analysis of occupational accidents and diseases and to identify factors causing those accidents. The SOC system is also used not only for surveillance of exposure to hazardous agents and occupational health, but to manage carcinogens. In order to adjust the effects of a particular job, SOC is used in the general population health area. The Ministry of Employment and Labor (MOEL) has never used or introduced an SOC system. There have been no cases of the application of a SOC system to either the occupational safety and health field or to health surveillance for the general population in Korea. Conclusions: We suggested a need to introduce an SOC system in several occupational safety and health activities, such as work environment measurement, analysis of occupational accidents, specific physical examination and surveillance systems, etc.

Structure Design and Experimental Appraisal of the Drag Force Type Vertical Axis Wind Turbine (수직축 항력식 풍력터빈의 구조설계 및 실험평가)

  • Kim Dong-Keon;Keum Jong-Yoon;Yoon Soon-Hyun
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.30 no.3 s.246
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    • pp.278-286
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    • 2006
  • Experiments were conducted to estimate the performance of drag force type vertical axis wind turbine with an opening-shutting rotor. It was operated by the difference in drag force generated on both sides of the blades. The rotational speed was measured by a tachometer in a wind tunnel and the tunnel wind speed was measured by using a pilot-static tube and a micro manometer. The performance test for a prototype was accomplished by calculating power, power coefficient, torque coefficient from the measurement of torque and rpm by a dynamometer controller. Various design parameters, such as the number of blades(B), blade aspect ratio(W/R), angle of blades$(\alpha)$ and drag coefficient acting on a blade, were considered for optimal conditions. At the experiment of miniature model, maximum efficiency was found at N=15, $\alpha=60^{\circ}$ and W/R=0.32. The measured test variables were power, torque, rotational speed, and wind speeds. The data presented are in the form of power and torque coefficients as a function of tip-speed ratio V/U. Maximum power was found in case of $\Omega=0.33$, when the power and torque coefficient were 0.14 and 0.37 respectively. Comparing model test with prototype test, similarity law by advance ratio for vertical axis wind turbine was confirmed.

The Image Position Measurement for the Selected Object out of the Center using the 2 Points Polar Coordinate Transform (2 포인트 극좌표계 변환을 이용한 중심으로부터의 목표물 영상 위치 측정)

  • Seo, Choon Weon
    • Journal of the Institute of Electronics and Information Engineers
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    • v.52 no.11
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    • pp.147-155
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    • 2015
  • For the image processing system to be classified the selected object in the nature, the rotation, scale and transition invariant features is to be necessary. There are many investigations to get the information for the object processing system and the log-polar transform which is to be get the invariant feature for the scale and rotation is used. In this paper, we suggested the 2 points polar coordinate transform methods to measure the selected object position out of the center in input image including the centroid method. In this proposed system, the position results of objects are very good, and we obtained the similarity ratio 99~104% for the object coordinate values.