• 한국통신학회논문지
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• 제23권8호
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• pp.2025-2031
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• 1998

MPEG2 동영상 압축 부호화는 비트율을 제어하는 방법에 따라서 압축율에 큰 영향을 미칠 뿐만 아니라 영상의 질도 좌우하게 된다. 본 논문은, I,P 프레임에 보다 많은 비트량을 할당하고, 인접 매크로블럭들의 MQUANT값들의 평균을 다음 매크로블럭의 양자화 값에 사용하는 비트 제어방법을 제안하였다. MPEG2 Test-Model5의 비트 제어방법과 비교하였을 때 제안한 방법은 약 0.9dB 정도의 화질이 향상됨을 보였다.

• 산경연구논집
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• 제11권10호
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• pp.59-73
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• 2020

Purpose: The ultimate purpose of this work is to investigate gender differences in the relationships between product quality cues and perceived values at a food select shop. Specifically, this study examines the effects of internal and external cues, which are indicators of product quality, on emotional and social values based on gender differences. Research design, data and methodology: In this study, a questionnaire technique was used to collect the data necessary to test the proposed model. 183 data were collected through this technique. PLS SEM (Partial Least Squares Structured Equation Model) was used to test the research model. Results: First, there is no gender difference between intrinsic cue and emotional value. When using male and female data, there was no significant causal relationship between intrinsic cues and emotional values. Second, we found no gender difference between intrinsic cue and social value. When analyzed with female data, there was no significant causal relationship between intrinsic cue and social value. On the other hand, in the case of men, it was found that a weak causal relationship exists. Third, this study found gender difference between extrinsic cue and emotional value. In the case of men, it was found that a weak causal relationship exists, whereas in the case of women, a strong causal relationship exists between extrinsic cue and emotional value. Fourth, we found gender difference between extrinsic cue and social value. In the case of men, there was no causal relationship, whereas in the case of women, there was a strong causal relationship between extrinsic cue and social value. Finally, we found that there are moderating roles of gender in the relationship between external cues and perceived quality. Conclusions: As a result of analysis, it is necessary to focus on extrinsic clues of product in order to increase the perceived emotional and social values of women. On the other hand, in order to improve the perceived emotional and social values of men, it is necessary to pay attention to both intrinsic and extrinsic cues of product. Therefore, it is necessary to consider what clues and values are important to core customers.

• 대한의용생체공학회:의공학회지
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• 제44권3호
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• pp.182-189
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• 2023

CT is a medical device that acquires medical images based on Attenuation coefficient of human organs related to X-rays. In addition, using this theory, it can acquire sagittal and coronal planes and 3D images of the human body. Then, CT is essential device for universal diagnostic test. But Exposure of CT scan is so high that it is regulated and managed with special medical equipment. As the special medical equipment, CT must implement quality control. In detail of quality control, Spatial resolution of existing phantom imaging tests, Contrast resolution and clinical image evaluation are qualitative tests. These tests are not objective, so the reliability of the CT undermine trust. Therefore, by applying an artificial intelligence classification model, we wanted to confirm the possibility of quantitative evaluation of the qualitative evaluation part of the phantom test. We used intelligence classification models (VGG19, DenseNet201, EfficientNet B2, inception_resnet_v2, ResNet50V2, and Xception). And the fine-tuning process used for learning was additionally performed. As a result, in all classification models, the accuracy of spatial resolution was 0.9562 or higher, the precision was 0.9535, the recall was 1, the loss value was 0.1774, and the learning time was from a maximum of 14 minutes to a minimum of 8 minutes and 10 seconds. Through the experimental results, it was concluded that the artificial intelligence model can be applied to CT implements quality control in spatial resolution and contrast resolution.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제16권5호
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• pp.1561-1583
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• 2022

Context: Testing is one of the techniques that can assure the quality of software including the domain of Software Product Line (SPL). Various techniques have been deliberated to enhance the quality of SPL including Model-based Testing (MBT). Objective: The objective of this study is to analyze and classify trends of MBT in SPL covering the solutions, issues and evaluation aspects by using taxonomy form. Method: A Systematic Literature Review (SLR) was conducted involving 63 primary studies from different sources. The selected studies were categorized based on their common characteristics. Results: Several findings can guide future research on MBT for SPL. The important finding is that the multiple measurements are still open to improving current metrics to evaluate test cases in MBT for SPL. The multiple types of measurement required a trade-off between maximization and minimization results to ensure the testing method which could satisfy multiple test criteria for example cost and effectiveness at the same time.

• 대한간호학회지
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• 제47권1호
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• pp.60-70
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• 2017

Purpose: This study was conducted to construct and test a structural equation model of health-related quality of life (HRQoL) among hospitalized patients with pulmonary tuberculosis (PTB). Methods: Participants were 256 patients with PTB who were 20 years or older and admitted in two national tuberculosis hospitals. The patients participated in pulmonary function testing and responded to structured questionaries. Results: The goodness-of-fit statistics of the final hypothetical model were as follows: ${\chi}^2/df=2.19$, RMSEA=.07, SRMR=.05, GFI=.95, NFI=.95, CFI=.96, TLI=.92, and PCFI=.52. Symptoms and general health perception had significant direct effects, and subjective economic status, social support and stigma had significant indirect effect on HRQoL of hospitalized patients with PTB. These variables explained 64% of variance in the prediction model. Conclusion: Findings suggest that strategies and intervention for physical symptoms and depressive symptoms are crucial to improve the quality of life in hospitalized patients with PTB. The development of various social support programs is also recommended.

• 한국수자원학회논문집
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• 제34권6호
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• pp.701-711
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• 2001

수질 인자들은 다양하고 관계가 복잡하여 수질 변화를 예측하는데 많은 어려움이 있다. 따라서 입력과 출력이 비교적 용이하고 비선형 예측에 적합한 신경망 모형을 이용하여 금강유역 공주지점의 DO, BOD, TN에 대한 월수질 예측을 수행하고 ARIMA 모형과 비교하여 적용 가능성을 검토하였다. 사용된 신경망 모형은 학습을 위해 BP(Back Propagation) 알고리즘을 적용하였으며 학습을 향상시키기 위한 모멘트-적응학습율(Moment-Adaptive learming rate) 방법을 이용한 MANN 모형, 레번버그-마쿼트(Levenberg-Marquardt) 방법을 이 용한 LMNN 모형, 그리고 정성적인 판단인자를 첨가하여 정량적인 월 수질 자료와 분별, 학습하 도록 은닉층을 분리한 MNN 모형으로 구분하였다. 대체로 신경망 모형의 예측치가 실측치에 근사한 결과를 보였으며, 은닉층을 분리한 MNN 모형이 가장 우수한 결과를 보였다.

• 한국주조공학회지
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• 제38권5호
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• pp.95-102
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• 2018

The dependence of the tensile properties on variations in the porosity of A356 aluminium alloys was investigated in terms of the quality index of the tensile properties based upon the ultimate tensile strength and elongation as well as the variation of the strength coefficient and strain-hardening exponent with regard to a T6 treatment. The test specimens were prepared by low-pressure die-casting and a subsequent T6 treatment, and the experimental results of a tensile test carried out at room temperature were compared to the theoretical description using a modified constitutive model. The nominal value of the quality index of A356 alloys increases gradually with a lapse of the ageing time upon a T6 treatment, despite the fact that this value is temporarily decreased during the initial stage of ageing from a solutionised condition. Additionally, the quality index depends practically upon the porosity variation with a power law relationship without regard to whether in solutionised or artificial aged conditions. The theoretical description indicates that the strength coefficient directly determines the nominal level of the quality index. Moreover, the overall dependence of the quality index on the porosity variation is remarkably weakened with an increase in the tensile strain, whereas the quality index depends sensitively upon the porosity variation with a low value of the strain-hardening exponent.

• 대한간호학회지
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• 제45권6호
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• pp.879-889
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• 2015

Purpose: The purpose of this study was to construct and test a structural equation model of quality of work life for clinical nurses based on Peterson and Wilson's Culture-Work-Health model (CWHM). Methods: A structured questionnaire was completed by 523 clinical nurses to analyze the relationships between concepts of CWHM-organizational culture, social support, employee health, organizational health, and quality of work life. Among these conceptual variables of CWHM, employee health was measured by perceived health status, and organizational health was measured by presenteeism. SPSS21.0 and AMOS 21.0 programs were used to analyze the efficiency of the hypothesized model and calculate the direct and indirect effects of factors affecting quality of work life among clinical nurses. Results: The goodness-of-fit statistics of the final modified hypothetical model are as follows: ${\chi}^2=586.03$, ${\chi}^2/df=4.19$, GFI=.89, AGFI=.85, CFI=.91, TLI=.90, NFI=.89, and RMSEA=.08. The results revealed that organizational culture, social support, organizational health, and employee health accounted for 69% of clinical nurses' quality of work life. Conclusion: The major findings of this study indicate that it is essential to create a positive organizational culture and provide adequate organizational support to maintain a balance between the health of clinical nurses and the organization. Further repeated and expanded studies are needed to explore the multidimensional aspects of clinical nurses' quality of work life in Korea, including various factors, such as work environment, work stress, and burnout.

• Asia Marketing Journal
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• 제7권2호
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• pp.1-22
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• 2005

본 연구는 거래지속기간에 따른 수출-수입업체간의 관계의 질에 대한 연구모형을 검토한 것이다. 연구모형은 지각된 유사성, 관계성과, 기회주의가 관계의 질에 영향을 주며, 거래 지속기간이 이들 관계에 조절변수로 작용하는 것으로 설정하였다. 또한 관계의 질은 결속에 영향을 주는 것으로 설정되었다. 연구가설의 검정을 위해 해외수출업체와 관계있는 수입업체 201개를 대상으로 설문조사를 실시하였다. 연구결과 대부분의 가설이 지지되었으며, 특히 지각된 유사성은 거래초기에는 관계의 질에 영향을 주지만, 거래후기에는 관계의 질에 유의한 영향을 미치지는 못하는 것으로 나타났으며, 기회주의는 거래초기보다 거래후기에 더욱 부정적인 역할을 하는 것으로 나타났다.

• 전자공학회논문지
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• 제52권7호
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• pp.143-152
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• 2015

품질경쟁력지수(QCI)는 전 세계에 유통 중인 제품의 품질을 객관적으로 측정할 수 있고, 정량적으로 비교할 수 있는 지표로 정의된다. 본 논문에서는 국내외 의류품 유통관리 시장에 보급되고 있는 UHF대역 RFID 라벨 태그(전세계 ISO 18000-3C지원)의 품질경쟁력지수 산출을 위한 평가모델을 제안한다. 품질경쟁력지수 평가모델은 KS표시품 품질우수성 지수(KS-QEI)모델을 기반으로 하고, 공정능력, 내환경성, 내구성, 설계마진 총 4가지의 평가항목으로 구성된다. 품질경쟁력지수는 가중산술 평균을 통해 평가항목 별 점수와 각 항목별 가중치를 각각 곱한 후 합산하는 방식으로 계산된다. 여기서 가중치는 국내외 산학연 전문가를 대상으로 AHP방식의 설문조사를 통해 결정되었다. 제안된 품질경쟁력지수는 글로벌 경쟁기업 제품과의 품질비교 결과 뿐만 아니라 이를 통해 우수한 품질의 국내 RFID 라벨 태그 정보를 제공할 수 있다. 또한 신제품을 개발하고자 하는 제조업체의 품질향상을 위해 중요한 역할을 할 것으로 기대된다.