• Title/Summary/Keyword: 신뢰성 측정

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An Empirical Analysis of Industrial Design′s Functional Role in the Causal Model of Quality Competitiveness : Korean Manufacturing Sector (품질경쟁력 인과모형 하에서 산업디자인의 기능적 역할에 관한 실증적 분석 : 한국 제조업 부문을 중심으로)

  • 임채숙;윤종영
    • Archives of design research
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    • v.17 no.3
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    • pp.111-122
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    • 2004
  • The purpose of this study are two the first is to identify the positioning of product design and analyze its functional relationship with product development, manufacturing, marketing and sales in the comprehensive competitiveness evaluation model ; and the second is to estimate the determinants of QCI(quality competitiveness index), analyze the impact of product design on QCI, and compare the aforementioned results for the seven industrial sectors and the five product patterns. For this empirical analysis, this study surveyed 400 Korean manufacturing firms during August-October 2003. The major empirical findings are summarized as follows : First, the hypothesis on the positive effect of product design on QCI is accepted at a highly significant level (p < 0.001) for all : the manufacturing sector, seven industrial sectors, and five product categories. Second, the correlation analysis and factor analysis lead to the result that the effect of product design on QCI is estimated to be relatively very low, in comparison to those of product functionality and basic performance on QCI. These findings imply that Korean manufacturing sector has been still in the prematured stage at which product design has not played an important role yet. This study concludes that product design in line with other functions (product development, manufacturing, marketing, and sales) should make a good contribution to the improvement of QCI in the future.

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Discovering Association Rules using Item Clustering on Frequent Pattern Network (빈발 패턴 네트워크에서 아이템 클러스터링을 통한 연관규칙 발견)

  • Oh, Kyeong-Jin;Jung, Jin-Guk;Ha, In-Ay;Jo, Geun-Sik
    • Journal of Intelligence and Information Systems
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    • v.14 no.1
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    • pp.1-17
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    • 2008
  • Data mining is defined as the process of discovering meaningful and useful pattern in large volumes of data. In particular, finding associations rules between items in a database of customer transactions has become an important thing. Some data structures and algorithms had been proposed for storing meaningful information compressed from an original database to find frequent itemsets since Apriori algorithm. Though existing method find all association rules, we must have a lot of process to analyze association rules because there are too many rules. In this paper, we propose a new data structure, called a Frequent Pattern Network (FPN), which represents items as vertices and 2-itemsets as edges of the network. In order to utilize FPN, We constitute FPN using item's frequency. And then we use a clustering method to group the vertices on the network into clusters so that the intracluster similarity is maximized and the intercluster similarity is minimized. We generate association rules based on clusters. Our experiments showed accuracy of clustering items on the network using confidence, correlation and edge weight similarity methods. And We generated association rules using clusters and compare traditional and our method. From the results, the confidence similarity had a strong influence than others on the frequent pattern network. And FPN had a flexibility to minimum support value.

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Properties of Blocking Filter as a function fo Magnetic Core shapes for Power Line Communication (자심재료의 형상에 따른 전력선 통신용 블로킹 필터의 특성)

  • Kim, Hyun-Sik;Lee, Hae-Yon;Ji, Min-Kwon;Oh, Young-Woo;Byun, Woo-Bong
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.11a
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    • pp.230-230
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    • 2007
  • 전력선 통신(Power Line Communication)은 최근 전력선을 이용한 통신기술의 발달과 더불어 세계적으로 관심도가 높아지고 연구 개발 및 자본 투자가 활발히 진행되고 있으며, 안정적인 네트워크를 구성하기 위해서는 고주파 전력선 통신 신호를 차단하는 블로킹 필터가 반드시 적용되어야 한다. 전력선 통신용 블로킹 필터는 광대역의 주파수 특성과 높은 신호감쇄 특성 및 대전류 특성이 요구되며, 이러한 특성을 구현하기 위해서는 블로킹 필터의 핵심부품인 자심재료의 고투자율 및 대전류화가 이루어져야 한다. 따라서 본 연구에서는 우수한 전 자기적 특성이 균일하게 유지되고, 전력선에 흐르는 대전류에 의한 자심재료의 포화가 발생하지 않도륵 새로운 자심 재료를 설계하여, 전력선 통신을 적용한 홈 네트워크 구축의 핵심 부품인 광대역 블로킹 필터를 개발하고자 하였다. 2350과 0.3 T의 투자율과 포화자속 밀도를 갖는 EI 형상의 자심재료를 해석모델로 설정하고 다중 에어 갭의 위치에 따른 전류와 자속밀도 변화를 유한요소 해석법으로 분석한 결과 자심재료의 대전류 특성에 지배적인 영향을 미치는 에어 캡의 삽입 위치를 알 수 있었고, 새로운 해석 모델인 I 형상의 로드(ROD) 코어에 대해 수치해석을 수행하여, 100A의 통전 전류에서도 자기적으로 포화되지 않고 인덕턴스의 정밀 제어가 가능하고, 특성의 신뢰성과 대전류에 대한 안정성을 증가시킬 수 있는 인덕터를 설계하였다. 또한 수동소자를 이용한 LC 공진회로를 기본 구성으로 하고, 주파수 대역, 신호 감쇄율과 대전류 특성, 상용화를 고려하여 블로킹 필터 회로를 설계하였으며, 유한요소해석법을 적용한 전자장 모의해석을 통하여 최소의 크기를 갖는 I 형상의 자심재료에 $6{\Phi}$의 에나멜 동선을 6.5턴, 6턴 권선하여 2.5, $2.15\;{\mu}H$의 인덕턴스를 갖는 직렬 인덕터를 구현하였고 블로킹 필터를 구성하였다. 주파수에 따른 신호감쇄 특성을 5 Hz~1 MHz의 주파수 범위에서 측정한 결과 약 490 kHz~450 kHz의 주파수 대역에서 -70dB의 신호감쇄 특성을 나타냈다. 본 연구를 통해 개발된 100A급 광대역 블로킹 필터가 적용되어 상용화 될 수 있을 것으로 판단되며, 또한 모뎀 통신 주파수 대역에서 -70dB 이상의 높은 감쇄 특성을 갖기 때문에 신호차단 특성이 보다 우수할 것으로 사료된다.

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Comparison of Linac-based VMAT Stereotatic Radiosurgery and Conventional Stereotatic Radiosurgery for Multiple Brain Lesions (Linac 기반 VMAT 정위적 수술 뇌 병변 연구와 기존의 정위적 방사선 수술 비교)

  • Jang, Eun-Sung;Chang, Bo-Seok
    • Journal of the Korean Society of Radiology
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    • v.15 no.2
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    • pp.239-246
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    • 2021
  • Portal Dosimetry was verified using EPID to secure the clinical application and reliability of the existing research dose evaluation. The dose distribution of Geant4 was compared with the measured value by 360° rotational irradiation with a 2.5 cm cone for stereotactic brain surgery. To confirm the dose distribution of patients with brain metastasis, the dose distribution investigated by inserting a Gafchromic EBT film into the parietal phantom and the dose distribution obtained from the parietal phantom using VMAT are compared and applied to actual patients. As a result of the analysis, it was confirmed that the accuracy of the beam center and the center of the couch coincide accurately with an error within 1mm as a result of QA through a pin ball. In addition, it was confirmed that the EBT3 film has excellent linearity in the range of 0 to 10 Gy according to various dose irradiation. In the same setting as the two cervical phantoms, we confirm that the implementation and simulation results calculations of dose calculations based on Geant4 using photon beams match the experimental data within the treatment planning volume (PTV). Therefore, volume modulated arc treatment (VMAT) 360° rotational irradiation was performed, and the result of iso-dose distribution analysis by rotational irradiation confirmed that it is appropriate to include a virtual tumor.

Calibration of cultivar parameters for cv. Shindongjin for a rice growth model using the observation data in a low quality (저품질 관측자료를 사용한 벼 생육 모델의 신동진 품종모수 추정)

  • Hyun, Shinwoo;Kim, Kwang Soo
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.21 no.1
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    • pp.42-54
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    • 2019
  • Crop models depend on a large number of input parameters including the cultivar parameters that represent the genetic characteristics of a given cultivar. The cultivar parameters have been estimated using high quality data for crop growth, which require considerable costs and efforts. The objective of this study was to examine the feasibility of using low quality data for the parameter estimation. In the present study, the cultivar parameters for cv. Shindongjin were estimated using the data obtained from the report of new cultivars development and research from 2005 to 2016. The root mean square errors (RMSE) of the heading dates were less than 3 days when the parameters associated with phenology were estimated. In contrast, the coefficient of determination for yield tended to be less than 0.1. The large errors incurred by the fact that no growth data collected over a season was used for parameter estimation. This suggests that detailed observation data needs to be prepared for parameter calibration, which would be aided by remote sensing approaches. The occurrence of natural disasters during a growing season has to be considered because crop models cannot take into account the effects of those events. Still, our results provide a reasonable range for the parameters, which could be used to set the boundary of a given parameter for cultivars similar to cv. Shindongjin in further studies.

Experimental Assessment and Specimen Height Effect in Frost Heave Testing Apparatus (동상시험장비의 실험적 검증 및 시료크기의 영향에 관한 연구)

  • Jin, Hyunwoo;Ryu, Byunghyun;Lee, Jangguen
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.1
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    • pp.67-74
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    • 2019
  • Frost heave is one of the representative engineering characteristics in cold regions. In South Korea, which is located in seasonal frost area, structural damage caused by frost heave and thaw happens and the need for research on the frost heave is increasing. In this paper, newly developed transparent temperature-controllable cell is used to focus on the frost heave. Frost susceptible artificial soil is used to analyze water intake rate which is one of the important factors in frost susceptibility criteria. Frost heave rate and water intake rate have similar behavior after heave by freezing of pore water converges. O-ring installed in the upper pedestal to measure water intake rate generates side friction between the inner wall of the freezing cell and O-ring, thereby hindering frost heave. Therefore, the frost susceptibility criteria using the water intake rate is not reliable. It is appropriate to use frost heave rate which has similar behavior with water intake rate. Frost heave tests were performed under two different specimen heights. Overburden pressure, temperature gradient and dry unit weight were set under similar state. Based on laboratory testing results, frost heave is independent on the specimen height.

The Validation of the Play Participation Attitude Scale for Parents of Preschoolers (영유아 부모의 놀이참여태도 척도 타당화 연구)

  • Lee, So-yean;Wui, Yeong-hee;Yoo, Jae-ryoung;Chyung, Yun-joo;Lee, Young-ae;Kim, Lee-jin
    • Korean Journal of Play Therapy
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    • v.21 no.4
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    • pp.491-507
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    • 2018
  • The purpose of this study is to validate the Play Participation Attitude Scale for parents of preschoolers, which was developed by the Delphi survey. 447 parents of 9 daycare centers in Seoul and Incheon were recruited for this study and, finally, data from 339 parents were used to perform exploratory factor analysis, confirmatory factor analysis, correlation analysis, multiple regression analysis, and reliability analysis. The results of the study are as follows. First, factor analyses revealed that the global fit of the sensitively play (7 items), responsively play (6 items), and delightfully play(7 items) three-factor model was good. Second, the internal consistency of the Play Participation Attitude Scale was good. Third, there was a statistically significant positive correlation between the current scale and the parents' playfulness scale, indicating concurrent validity. Finally, higher scores of the Play Participation Attitude Scale and its three factors significantly predicted lower scores of parenting stress and higher scores of the preschoolers' self-control ability. These findings revealed that this new measure to be both valid and reliable and specifically suggests what kind of attitude is appropriate for parents to adopt when participating in preschoolers' play.

Analysis of Job Characteristics for Ultrasound Examination of Radiological Technologists in Yeongnam Area (영남지역 방사선사의 초음파검사 직무특성 분석)

  • Jeong, Bong-Jae;Lee, Sang-Hun
    • Journal of the Korean Society of Radiology
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    • v.16 no.5
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    • pp.639-647
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    • 2022
  • This study analyzed the job characteristics of radiological technologists in charge of ultrasound examinations in the Yeongnam region. The measuring tool used in the study was a questionnaire, and the subjects were radiological technologists in charge of ultrasound examination at medical institutions located in the Yeongnam region from August 01 to November 30, 2021. In consideration of the COVID-19 situation, statistical analysis was performed using the SPSS/PC Ver 18.0 program using e-mail and SNS in a non-face-to-face manner with 158 questionnaires. As a result of analyzing the job characteristics of the radiological technologists in charge of ultrasound examination, the job satisfaction was 3.24±0.61. In the effect of job characteristic factors on job satisfaction, professional position, self-esteem, and trust relationship formation were found to be higher than the average of 3.0. However, as the dissatisfaction factor, compensation and appropriateness of work were cited. Therefore, in order to improve the job characteristics and satisfaction level of radiological technologists in charge of ultrasound examinations, it is necessary to do their best to improve the appropriate work environment of medical institutions and to continuously secure professionalism of radiological technologists in charge of ultrasound examinations.

Development and validation of a Korean Affective Voice Database (한국형 감정 음성 데이터베이스 구축을 위한 타당도 연구)

  • Kim, Yeji;Song, Hyesun;Jeon, Yesol;Oh, Yoorim;Lee, Youngmee
    • Phonetics and Speech Sciences
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    • v.14 no.3
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    • pp.77-86
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    • 2022
  • In this study, we reported the validation results of the Korean Affective Voice Database (KAV DB), an affective voice database available for scientific and clinical use, comprising a total of 113 validated affective voice stimuli. The KAV DB includes audio-recordings of two actors (one male and one female), each uttering 10 semantically neutral sentences with the intention to convey six different affective states (happiness, anger, fear, sadness, surprise, and neutral). The database was organized into three separate voice stimulus sets in order to validate the KAV DB. Participants rated the stimuli on six rating scales corresponding to the six targeted affective states by using a 100 horizontal visual analog scale. The KAV DB showed high internal consistency for voice stimuli (Cronbach's α=.847). The database had high sensitivity (mean=82.8%) and specificity (mean=83.8%). The KAV DB is expected to be useful for both academic research and clinical purposes in the field of communication disorders. The KAV DB is available for download at https://kav-db.notion.site/KAV-DB-75 39a36abe2e414ebf4a50d80436b41a.

Analysis of Influence Factors on the Satisfaction of Viewers on China's CCTV-9 Channel (중국 CCTV-9 채널 시청자의 프로그램 관람 만족도 결정요인 분석)

  • Guo, Yuan;Wang, Zhifeng
    • Journal of Korea Entertainment Industry Association
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    • v.15 no.8
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    • pp.107-116
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    • 2021
  • In recent years, the research on audience satisfaction after watching programs has been carried out in various fields. However, there is no precedent for the study of simply analyzing the influencing factors of audience satisfaction with the newly established CCTV-9 channel. For CCTV-9, how to explore the strategy of industrial development based on the needs of the audience in the era of big data is a very important part. This article exploratively focuses on the influencing factors related to CCTV-9 audience satisfaction. Using questionnaires, 101 samples of the satisfaction with the channel of men and women of different ages, education backgrounds, majors, and incomes were collected to test, and 9 hypotheses were tentatively proposed as relevant influencing factors of channel satisfaction. Through empirical analysis, this research searches for the determinants. The reliability and validity of the measurement were properly analyzed, and all hypotheses were statistically tested. The empirical results show that: subject matter, program format, program scheduling, program broadcast time, channel advertising, simulcast series of documentaries, diversified communication platforms, brand image packaging and audience satisfaction are significantly positively correlated.