• 제목/요약/키워드: model-based software testing

검색결과 242건 처리시간 0.029초

자동차용 연료펌프의 진동 저감에 대한 연구 (A Study on the Vibration Reduction of an Automobile Fuel Pump)

  • 김병진;원홍인;이성원;박상준;정진태
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2013년도 춘계학술대회 논문집
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    • pp.772-777
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    • 2013
  • This article presents the reduction of vibration generated by an automobile fuel pump. In order to analysis the vibration of the fuel pump, a simplified dynamic model is established, which is composed of a rigid rotor and a equivalent springs. The equivalent stiffnesses of the upper and lower assemblies are evaluated by the comparison of modal testing results and the finite element analysis. the stiffness for the oil film of the journal bearing is extracted by using Reynold's equation. In addition, the time responses for the vibration of the fuel pump are computed by using a commercial multi-body dynamics software, RecurDyn. Based on these results, some design suggestions are proposed to reduce the vibration of an automobile fuel pump.

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Fake News Detection Using Deep Learning

  • Lee, Dong-Ho;Kim, Yu-Ri;Kim, Hyeong-Jun;Park, Seung-Myun;Yang, Yu-Jun
    • Journal of Information Processing Systems
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    • 제15권5호
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    • pp.1119-1130
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    • 2019
  • With the wide spread of Social Network Services (SNS), fake news-which is a way of disguising false information as legitimate media-has become a big social issue. This paper proposes a deep learning architecture for detecting fake news that is written in Korean. Previous works proposed appropriate fake news detection models for English, but Korean has two issues that cannot apply existing models: Korean can be expressed in shorter sentences than English even with the same meaning; therefore, it is difficult to operate a deep neural network because of the feature scarcity for deep learning. Difficulty in semantic analysis due to morpheme ambiguity. We worked to resolve these issues by implementing a system using various convolutional neural network-based deep learning architectures and "Fasttext" which is a word-embedding model learned by syllable unit. After training and testing its implementation, we could achieve meaningful accuracy for classification of the body and context discrepancies, but the accuracy was low for classification of the headline and body discrepancies.

국내 MIS 연구에서 구조방정식모형 활용에 관한 메타분석 (A Meta Analysis of Using Structural Equation Model on the Korean MIS Research)

  • 김종기;전진환
    • Asia pacific journal of information systems
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    • 제19권4호
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    • pp.47-75
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    • 2009
  • Recently, researches on Management Information Systems (MIS) have laid out theoretical foundation and academic paradigms by introducing diverse theories, themes, and methodologies. Especially, academic paradigms of MIS encourage a user-friendly approach by developing the technologies from the users' perspectives, which reflects the existence of strong causal relationships between information systems and user's behavior. As in other areas in social science the use of structural equation modeling (SEM) has rapidly increased in recent years especially in the MIS area. The SEM technique is important because it provides powerful ways to address key IS research problems. It also has a unique ability to simultaneously examine a series of casual relationships while analyzing multiple independent and dependent variables all at the same time. In spite of providing many benefits to the MIS researchers, there are some potential pitfalls with the analytical technique. The research objective of this study is to provide some guidelines for an appropriate use of SEM based on the assessment of current practice of using SEM in the MIS research. This study focuses on several statistical issues related to the use of SEM in the MIS research. Selected articles are assessed in three parts through the meta analysis. The first part is related to the initial specification of theoretical model of interest. The second is about data screening prior to model estimation and testing. And the last part concerns estimation and testing of theoretical models based on empirical data. This study reviewed the use of SEM in 164 empirical research articles published in four major MIS journals in Korea (APJIS, ISR, JIS and JITAM) from 1991 to 2007. APJIS, ISR, JIS and JITAM accounted for 73, 17, 58, and 16 of the total number of applications, respectively. The number of published applications has been increased over time. LISREL was the most frequently used SEM software among MIS researchers (97 studies (59.15%)), followed by AMOS (45 studies (27.44%)). In the first part, regarding issues related to the initial specification of theoretical model of interest, all of the studies have used cross-sectional data. The studies that use cross-sectional data may be able to better explain their structural model as a set of relationships. Most of SEM studies, meanwhile, have employed. confirmatory-type analysis (146 articles (89%)). For the model specification issue about model formulation, 159 (96.9%) of the studies were the full structural equation model. For only 5 researches, SEM was used for the measurement model with a set of observed variables. The average sample size for all models was 365.41, with some models retaining a sample as small as 50 and as large as 500. The second part of the issue is related to data screening prior to model estimation and testing. Data screening is important for researchers particularly in defining how they deal with missing values. Overall, discussion of data screening was reported in 118 (71.95%) of the studies while there was no study discussing evidence of multivariate normality for the models. On the third part, issues related to the estimation and testing of theoretical models on empirical data, assessing model fit is one of most important issues because it provides adequate statistical power for research models. There were multiple fit indices used in the SEM applications. The test was reported in the most of studies (146 (89%)), whereas normed-test was reported less frequently (65 studies (39.64%)). It is important that normed- of 3 or lower is required for adequate model fit. The most popular model fit indices were GFI (109 (66.46%)), AGFI (84 (51.22%)), NFI (44 (47.56%)), RMR (42 (25.61%)), CFI (59 (35.98%)), RMSEA (62 (37.80)), and NNFI (48 (29.27%)). Regarding the test of construct validity, convergent validity has been examined in 109 studies (66.46%) and discriminant validity in 98 (59.76%). 81 studies (49.39%) have reported the average variance extracted (AVE). However, there was little discussion of direct (47 (28.66%)), indirect, and total effect in the SEM models. Based on these findings, we suggest general guidelines for the use of SEM and propose some recommendations on concerning issues of latent variables models, raw data, sample size, data screening, reporting parameter estimated, model fit statistics, multivariate normality, confirmatory factor analysis, reliabilities and the decomposition of effects.

위험관리 기반의 비용 효율적인 실시간 웹 애플리케이션 소프트웨어 보안취약점 테스팅 (Cost-Effective, Real-Time Web Application Software Security Vulnerability Test Based on Risk Management)

  • 쿠미 산드라;임채호;이상곤
    • 정보보호학회논문지
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    • 제30권1호
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    • pp.59-74
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    • 2020
  • 웹 애플리케이션이 동작하는 웹 공간은 공개된 HTML로 인하여 공격자와 방어자의 사이버 정보전쟁터이다. 사이버 공격 공간에서 웹 애플리케이션과 소프트웨어 취약성을 이용한 공격이 전 세계적으로 약 84%이다. 웹 방화벽 등의 보안제품으로 웹 취약성 공격을 탐지하기가 매우 어렵고, 웹 애플리케이션과 소프트웨어의 보안 검증과 보증에 많은 인건비가 필요하다. 따라서 자동화된 소프트웨어에 의한 웹 스페이스에서의 신속한 취약성 탐지와 대응이 핵심적이고 효율적인 사이버 공격 방어 전략이다. 본 논문에서는 웹 애플리케이션과 소프트웨어에 대한 보안 위협을 집중적으로 분석하여 보안위험 관리 모델을 수립하고, 이를 기반으로 효과적인 웹 및 애플리케이션 취약성 진단 방안을 제시한다. 실제 상용 서비스에 적용한 결과를 분석하여 기존의 다른 방식들보다 더 효과적임을 증명한다.

BYOD 환경의 MDM 보안솔루션의 품질평가모델에 관한 연구 (A Study on Quality Evaluation Model of Mobile Device Management for BYOD)

  • 나현대;강수경;김창재;이남용
    • 컴퓨터교육학회논문지
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    • 제17권6호
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    • pp.93-102
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    • 2014
  • 모바일 오피스 환경이 점차 증가하여 스마트폰 태블릿 PC 기기 등 모바일 장비가 기업, 학교, 공공기관 등 장소에 구애 받지 않고 많이 활용되고 있다. 이에 따른 보안 위협도 지속적으로 발생하여 효과적인 보안 관리정책과 기술적 보안이 요구되고 있다. 이러한 BYOD(Bring Your Own Device) 환경에서 기술적인 보안을 위한 해결책으로 네트워크기반통제 솔루션, MDM(Mobile Device Management), MAM(Mobile Application Management), MCM(Mobile Contents Management)등이 출시되어 정보 보안에 활용되고 있다. 그러나 BYOD의 보안 솔루션을 선정함에 있어 표준 가이드라인 및 품질 평가 기준이 미흡하여 품질 평가 모델이 요구되고 있다. 본 논문에서는 최근 가장 범용적으로 사용되고 있는 MDM 솔루션을 선택하여 그 특징을 살펴보고 ISO/IEC25010의 소프트웨어 품질특성에 기반을 두어 제품 속성 분석 및 품질 평가 요소를 도출, 관련 메트릭스를 산출하였다. 품질 평가 모델 검증을 위해 보안점검 항목 및 테스트 수행 방안을 정하고 사례연구를 통하여 메트릭스를 적용하고 분석하였다.

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상관관계를 통한 조직의 테스트 프로세스 개선 가이드 방안 (Guideline for Test Process Improvement of Test Organization Through Correlating TMMi with TPI NEXT)

  • 김기두;박용범;김영철
    • 정보처리학회논문지:소프트웨어 및 데이터공학
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    • 제2권12호
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    • pp.823-828
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    • 2013
  • 본 논문에서는 기본적인 TMMi 레벨 인증으로부터 정형화된 올바른 테스트 프로세스를 적용하여 소프트웨어의 품질을 높이고자 한다. 조직의 테스트 성숙도 수준 평가 모델인 TMMi과 테스트 프로세스를 개선 모델인 TPI NEXT의 분석을 통해 상관 관계도를 제안하고, 그 기반에서 조직의 테스트 성숙도 측정으로 테스트 프로세스 향상을 위한 가이드를 제공하고자 한다. 또한 기존의 테스트 성숙도 상호관련 메트릭의 보완 및 개선 통해 성숙도 측정을 도식화 한다. 제한된 레벨 수준의 사례로 TMMi와 TPI NEXT의 상관 관계도와 보완한 테스트 성숙도 상호관련 메트릭을 통해 조직의 테스트 프로세스 개선을 위한 가이드를 보여준다.

A High-Performance Sensorless Control System of Reluctance Synchronous Motor with Direct Torque Control

  • Kim Min-Huei;Kim Nam-Hun;Choi Kyeong-Ho;Kim Dong-Hee;Hwang Dong-Ha
    • 전력전자학회:학술대회논문집
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    • 전력전자학회 2001년도 Proceedings ICPE 01 2001 International Conference on Power Electronics
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    • pp.355-359
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    • 2001
  • This paper presents an implementation of digital control system of speed sensorless for Reluctance Synchronous Motor (RSM) drives with DTC. The control system consists of stator flux observer, rotor position/speed/torque estimator, two hysteresis band controllers, an optimal switching look-up table, IGBT voltage source inverter, and TMS320C31 DSP controller by using fully integrated control software. The stator flux observer is based on the combined voltage and current model with stator flux feedback adaptive control that inputs are current and voltage sensing of motor terminal with estimated rotor angle for wide speed range. The rotor position is estimated by observed stator flux-linkage space vector. The estimated rotor speed is determined by differentiation of the rotor position used only in the current model part of the flux observer for a low speed operating area. It does not require the knowledge of any motor parameters, nor particular care for motor starting, In order to prove the suggested control algorithm, we have a simulation and testing at actual experimental system. The developed sensorless control system is shown a good speed control response characteristic results and high performance features in 50/1000 rpm with 1.0Kw RSM having 2.57 ratio of d/q reluctance.

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직접토크제어에 의한 리럭턴스 동기전동기의 고성능 제어시스템 (A High-Performance Control System of Reluctance Synchronous Motor with Direct Torque Control)

  • 김민회;김남훈;김민호
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 학술대회 논문집 전문대학교육위원
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    • pp.47-52
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    • 2001
  • This paper presents a high-performance control system for Reluctance Synchronous Motor (RSM) drives with direct torque control (DTC). The system consist of stator flux observer, rotor position/speed estimator, torque estimator, two hysteresis band controllers, an optimal switching look-up table, IGBT voltage source inverter, and F240/C31DSP controller by using fully integrated control software. The stator flux observer is based on the combined voltage and current model with stator flux feedback adaptive control that inputs are current and voltage sensing of motor terminal with estimated rotor angle for wide speed range. The rotor position is estimated by the observed stator flux-linkage space vector. The estimated rotor speed can be determinated by differentiation of the rotor position used only in the current model part of the flux observer for a low speed operating area. To prove the suggested control algorithm, we have a simulation and testing at actual experimental system. The developed digitally high-performance position sensorless control system are shown a good motion control response characteristic results and high performance features using 1.0Kw RSM.

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직접 토크제어에 의한 리럭턴스 동기 전동기의 센서리스 제어시스템 (A Sensorless control system of Reluctance Synchronous Motor with Direct Torque Control)

  • 김민회;김남훈;백원식;김동희
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 추계학술대회 논문집 전기기기 및 에너지변환시스템부문
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    • pp.161-164
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    • 2001
  • This paper presents a digital speed sensorless control system for Reluctance Synchronous Motor (RSM) drives with direct torque control (DTC). The system consist of stator flux observer, rotor speed estimator, torque estimator two hysteresis band controllers, an optimal switching look-up table. IGBT voltage source inverter, and TMS320C31DSP controller by using fully integrated control software. The stator flux observer is based on the combined voltage and current model with stator flux feedback adaptive control that inputs are current and voltage sensing of motor terminal with estimated rotor angle for wide speed range. The rotor speed is estimated by the observed stator flux-linkage space vector. The estimated rotor speed can be determinated by differentiation of the rotor position used only in the current model part of the flux observer for a low speed operating area. In order to prove the suggested speed sensorless control algorithm. There are some simulation and testing at actual experimental system. The developed digitally high- performance speed sensorless control system are shown a good speed control response characteristic results and high Performance features using 1.0Kw RSM.

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Purchase Intention Towards Japanese Convenience Goods: A Cross-Sectional Study in Vietnam

  • NGUYEN, Nga Thi Quynh;NGUYEN, Duong Tuan;NGUYEN, Quynh Thi Phuc
    • The Journal of Asian Finance, Economics and Business
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    • 제8권10호
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    • pp.165-176
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    • 2021
  • The primary purpose of this study is to identify determinants influencing Vietnamese consumers' purchase intention towards Japanese convenience goods. The research model consisting of six factors affecting the dependent variable is proposed based on the Theory of Consumption Values and Theory of Perceived Value of purchase. This study employs a survey method in a convenient sampling method to collect data of target respondents. Data consisting of 180 samples was collected and analyzed using the SMARPLS3 software. The measurement model is assessed to confirm the validity and reliability of the construct, then hypotheses testing is performed with Bootstrapping analysis. The results demonstrated that five factors affect Vietnamese consumers' purchase intention towards Japanese convenience goods, including the price of the product, quality of the product, functional value, emotional value, and conditional value. Major findings of this study suggest that the functional value that consumer perceives about Japanese convenience goods has the most significant relationship with their purchase intention, followed by the quality of the product and the price of the product. Besides, emotional value and conditional value have a moderate influence on consumers' purchase intention. Whereas the influence of the epistemic value of the product on consumers' purchase intention is insignificant in this presented study.