• 한국산업정보학회논문지
• /
• 제29권1호
• /
• pp.49-62
• /
• 2024

본 연구는 국내 모바일폰 산업을 위한 지속가능한 폐쇄루프 공급망 (Sustainable closed-loop supply chain: SCLSC) 네트워크 모델을 제안한다. 제안된 SCLSC 네트워크 모델의 지속 가능성을 위해 경제적, 환경적, 사회적 요인들이 각각 고려된다. 이들 세 가지 요인들은 SCLSC 네트워크 모델의 각 단계에서 고려되는 설비의 구축 및 운영으로부터 발생하는 총비용 최소화, CO₂ 방출 총량 최소화, 사회적 영향력 최대화를 목표로 한다. 이러한 목표들은 SCLSC 네트워크의 모델링 단계에서 각각 개별적인 목적함수로 고려되어야 하기 때문에 SCLSC 네트워크 모델은 다목적 최적화 문제로 간주할 수 있다. SCLSC 네트워크 모델은 수리모델을 사용하여 표현되며, 혼합형 메타휴리스틱 접근법을 수리모델에 적용하여 그 해를 구한다. 수치실험에서는 제안된 혼합형 메타휴리스틱 접근법의 수행도가 기존의 메타휴리스틱 접근법들의 수행도와 비교된다. 실험결과는 본 연구에서 제안된 혼합형 메타휴리스틱 접근법이 기존의 메타휴리스틱 접근법들과 비교하여 더 뛰어난 수행도를 보여주는 것을 알 수 있다.

• 한국전자통신학회논문지
• /
• 제16권1호
• /
• pp.95-100
• /
• 2021

본 논문에서는 수중 건설 로봇을 제어하기 위한 모델 기반 메타 강화 학습 방법을 제안한다. 모델 기반 메타 강화 학습은 실제 응용 프로그램의 최근 경험을 사용하여 모델을 빠르게 업데이트한다. 다음으로, 대상 위치에 도달하기 위해 매니퓰레이터의 제어 입력을 계산하는 모델 예측 제어로 모델을 전송한다. MuJoCo 및 Gazebo를 사용하여 모델 기반 메타 강화 학습을 위한 시뮬레이션 환경을 구축하였으며 수중 건설 로봇의 실제 제어 환경에서의 모델 불확실성을 포함하여 제안한 방법을 검증하였다.

• Asian Pacific Journal of Cancer Prevention
• /
• 제13권8호
• /
• pp.3717-3721
• /
• 2012

Purpose: Any association between the CYP1A1 Ile462Val polymorphism and endometrial cancer risk remains inconclusive. For a more precise estimate, we performed the present meta-analysis. Methods: PUBMED, OVID and EMBASE were searched for the studies which met inclusion criteria. Data in all eligible studies were evaluated and extracted by two authors independently. The meta-analysis estimated pooled odds ratio (OR) with 95% confidence interval (CI) for endometrial cancer risk attributable to the CYP1A1 Ile462Val polymorphism. Results: A total of 7 studies were included in this meta-analysis. The results indicated no association between endometrial cancer risk and the CYP1A1 Ile462Val polymorphism (for Val vs Ile allele model [OR 1.09, 95% CI 0.73-1.62]; for Val.Val vs Ile.Ile genotype model [OR 1.54, 95% CI 0.56-4.23]; for (Ile.Val + Val.Val) vs Ile.Ile genotpye model [OR 1.08, 95% CI 0.71-1.63]; for Val.Val vs (Ile.Ile + Ile.Val) genotype model [OR 1.46, 95% CI 0.53-4.04]). Conclusions: This meta-analysis suggests that there is no association between endometrial cancer risk and the CYP1A1 Ile462Val polymorphism.

• 한국기계가공학회지
• /
• 제18권3호
• /
• pp.74-81
• /
• 2019

Herein, we performed a comparative study on approximate multi-objective design optimization, to realize a structural design to improve the weight and vibration performances of the knuckle - a car suspension component - considering various load conditions and vibration characteristics. In the approximate multi-objective optimization process, a regression meta-model was generated using the response surfaces method (RSM), while Kriging and back-propagation neural network (BPN) methods were applied for interpolation meta-modeling. The Pareto solutions, multi-objective optimal solutions, were derived using the non-dominated sorting genetic algorithm (NSGA-II). In terms of the knuckle design considered in this study, the characteristics and influence of the meta-model on multi-objective optimization were reviewed through a comparison of the approximate optimization results with the meta-models and the actual optimization.

• International journal of advanced smart convergence
• /
• 제8권4호
• /
• pp.68-74
• /
• 2019

Along with the deeper architecture in the deep learning approaches, the need for the data becomes very big. In the real problem, to get huge data in some disciplines is very costly. Therefore, learning on limited data in the recent years turns to be a very appealing area. Meta-learning offers a new perspective to learn a model with this limitation. A state-of-the-art model that is made using a meta-learning framework, Meta-SGD, is proposed with a key idea of learning a hyperparameter or a learning rate of the fast adaptation stage in the outer update. However, this learning rate usually is set to be very small. In consequence, the objective function of SGD will give a little improvement to our weight parameters. In other words, the prior is being a key value of getting a good adaptation. As a goal of meta-learning approaches, learning using a single gradient step in the inner update may lead to a bad performance. Especially if the prior that we use is far from the expected one, or it works in the opposite way that it is very effective to adapt the model. By this reason, we propose to add a weight term to decrease, or increase in some conditions, the effect of this prior. The experiment on few-shot learning shows that emphasizing or weakening the prior can give better performance than using its original value.

• 한국습지학회지
• /
• 제11권1호
• /
• pp.49-64
• /
• 2009

홍수나 가뭄 등 극한 사상을 예측하여 재해에 대비하거나 또는 수자원을 효율적으로 관리, 배분하기 위하여 강우-유출 모형이 이용되고 있다. 그러나 많은 수문학자들은 강우-유출 모형이 가질 수밖에 없는 불확실성에 대하여 언급하였다. 실제 유역에 내린 강우는 증발과 증산, 차단, 침투 등 여러 과정을 거쳐 유출로 이어지는데, 모형에서는 이러한 복잡한 물리적 과정을 단순화하여 표현하였으므로 불확실성이 반드시 존재할 수밖에 없는 것이다. 따라서 모형으로부터의 모의 결과를 신뢰할 수 있는지를 정량적으로 판단하는 과정이 이루어져야 한다. 본 논문에서는 현재까지 강우-유출 모형의 불확실성을 평가한 선행 연구 중 Montanari와 Brath(2004)가 제시한 Meta-Gaussian 기법을 이용하여 강우-유출 모형 모의 결과에 대한 불확실성을 검토하였다. 이 기법은 모형 오차의 확률 분포형으로부터 신뢰구간의 상한계와 하한계를 추정하는 방법으로 수문모형의 전역적 불확실성(Global Uncertainty)을 정량화할 수 있다. 본 논문에서는 동일한 강우사상에 대한 물리적 기반의 분포형 모형인 $Vflo^{TM}$ 모형과 개념적 준 분포형 모형인 HEC-HMS 모형으로부터 모의된 유출량을 Meta-Gaussian 기법을 적용하여 불확실성을 분석하였다.

• 산업경영시스템학회지
• /
• 제23권56호
• /
• pp.19-34
• /
• 2000

Impact of business process re-engineering requires the fundamental rethinking of how information systems are analyzed and designed. It is no longer sufficient to establish a monolithic system for fixed business environments. Information systems must be adaptive in nature. This demand is also applied in production domain. Enabling concept for the adaptive information system is reusability. This paper presents a new object-oriented analysis process for creating such reusable software components in production domain, especially for production planning and scheduling. Our process called MeCOMA is based on three meta-models: physical object meta-model, data object meta-model, and activity object meta-model. After the three meta-models are extended independently for a given production system, they are collaboratively integrated on the basis of integration pattern. The main advantages of MeCOMA are (1) to reduce software development time and (2) to consistently build reusable production software components.

• 한국컴퓨터산업교육학회:학술대회논문집
• /
• 한국컴퓨터산업교육학회 2003년도 제4회 종합학술대회 논문집
• /
• pp.127-133
• /
• 2003

The data models which express all types of video information physically and logically. and the definition of spatiotemporal relationship of video data objects In This paper, we classifies meta-model for efficient management on spatiotemporal relationship between two objects in video image data, suggests meta-models based on Rambaugh's OMT technique, and expanded user model to apply the adaptive model, established from hyper-media or web agent to VOD. The proposed meta-model uses data's special physical feature: the effects of camera's and editing effects of shot, and 17 spatial relations on Allen's 13 temporal relations, topology and direction to include logical presentation of spatiotemporal relation for possible spatiotemporal reference and having unspecified applied mediocrity.

• 대한간호학회지
• /
• 제52권4호
• /
• pp.363-377
• /
• 2022

Purpose: This study aimed to test a hypothetical model of Korean nurses' patient safety management activities using meta-analytic path analysis. Methods: A systematic review, meta-analysis, and meta-analytic path analysis were conducted following the PRISMA and MOOSE guidelines. Seventy-four studies for the meta-analysis and 92 for the meta-analytic path analysis were included. The R software program (Version 3.6.3) was used for data analysis. Results: Four variables out of 49 relevant variables were selected in the meta-analysis. These four variables showed large effect sizes (ESr = .54) or median effect sizes (ESr = .33~.40) with the highest k (number of studies) in the individual, job, and organizational categories. The hypothetical model for the meta-analytic path analysis was established using these variables and patient safety management activities. Twelve hypothetical paths were set and tested. Finally, the perception of the importance of patient safety management and patient safety competency directly affected patient safety management activities. In addition, self-efficacy, the perception of the importance of patient safety management, patient safety competency, and patient safety culture, indirectly affected patient safety management activities. Conclusion: Self-efficacy, the perception of the importance of patient safety management, patient safety competency, and the organization's patient safety culture should be enhanced to improve nurses' patient safety management activities.

• 대한간호학회지
• /
• 제50권6호
• /
• pp.757-777
• /
• 2020

Purpose: The purpose of this study was to identify the outcome variables of nursing unit managers' transformational leadership and to test a hypothetical model using meta-analytic path analysis. Methods: A systematic review and meta-analysis were conducted in accordance with PRISMA guidelines. Data analysis, conducted using R version 3.6.2 software, included 49 studies for the meta-analysis and 119 studies for meta-analytic path analysis. Results: In the meta-analysis, four out of 32 outcome variables were selected. These four variables were empowerment, nursing performance, job satisfaction, and organizational commitment, which showed larger effect sizes than the median and more than five k. The hypothetical model for the meta-analytic path analysis was established by using these four variables and transformational leadership. A total of 22 hypothetical paths including nine direct effects and 13 indirect effects were set and tested. The meta-analytic path analysis showed that transformational leadership had direct effects on the four variables. Finally, eight direct effects, 12 indirect effects, and six mediating effects were statistically significant, and the hypothetical model was verified. Conclusion: Nursing unit managers can use the transformational leadership to improve empowerment, nursing performance, job satisfaction, and organizational commitment of nurses. This study empirically showed the importance of transformational leadership of nursing managers. This finding will be used as evidence to develop strategies for enhancing transformational leadership, empowerment, nursing performance, job satisfaction, and organizational commitment in nursing science and practice.