• KIEAE Journal
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• 제17권3호
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• pp.35-44
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• 2017

Purpose: This study questioned the efficiency of daylight factor as a daylight adequacy and investigated a method of how to complement its weakness by considering a direct sunlight component under a clear sky condition. Method: The Snowdon visitor centre cafe was chosen as a case study building and various techniques such as BRE formula, BRE sky protractor, Pilkington dot diagram and mock-upscale model under the artificial sky simulator were used to analyse and compare daylight factor values. An analysis of direct sunlight component under the clear sky condition was carried out by Climate Consultant 5.5, sun path diagram, and the artificial sky simulator. Result: The result of daylight factor analysis differed by the adopted techniques and it was also contradictory to the results on a direct sunlight penetration. The result not only showed the limitation of daylight factor as a metric but also suggested an improvement by combining it with direct sunlight analysis. The techniques used in this study had a merit of being applied in the early design stage and thus be beneficial to many design professions in order for early daylight performance analysis.

• 한국정밀공학회지
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• 제18권2호
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• pp.199-205
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• 2001

Burr makes troubles on manufacturing process due to deburring cost, quality of products and productivity. This paper described the results of experimental study on the influence of the cutting parameters on the formation of exit burrs in face milling. Using the results of experimental study, burr types are classified and data bases are developed to predict burr formation result. From the CAD file for work geometry and the NC data for tool path, the exit angles are calculated at every edges. This program predicts the burr geometry at exit edges using the prediction algorithm and data bases which are developed experimentally. Simulation results on deformation strain and temperature are also available in specific 2-dimensional cutting conditions. Also algorithm which can determine the exit angle is proposed.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.800-811
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• 2014

Recent developments in the prediction of the contribution of windnoise to the interior SPL have opened a realm of new possibilities in terms of i) how the convective and acoustic sources terms can be identified, ii) how the interaction between the source terms and the side glass can be described and finally iii) how the transfer path from the sources to the interior of the vehicle can be modelled. This work discusses in details these three aspects of wind noise simulation and recommends appropriate methods to deliver required results at the right time based on i) simulation and experimental data availability, ii) design stage at which a decision must be made and iii) time available to deliver these results. Several simulation methods are used to represent the physical phenomena involved such as CFD, FEM, BEM, FE/SEA Coupled and SEA. Furthermore, a 1D and 2D wavenumber transformation is used to extract key parameters such as the convective and the acoustic component of the turbulent flow from CFD and/or experimental data whenever available. This work focuses on the validation of the wind noise source characterization method and the vibro-acoustic models on which the wind noise sources are applied.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2014년도 추계학술대회 논문집
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• pp.563-564
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• 2014

Recent developments in the prediction of the contribution of windnoise to the interior SPL have opened a realm of new possibilities in terms of i) how the convective and acoustic sources terms can be identified, ii) how the interaction between the source terms and the side glass can be described and finally iii) how the transfer path from the sources to the interior of the vehicle can be modelled. This work discusses several simulation methods that can be used to represent the physical phenomena involved such as CFD, FEM, BEM, FE/SEA Coupled and SEA. This work focuses on the validation of the wind noise source characterization method and the vibro-acoustic models on which the wind noise sources are applied in the framework of a benchmark proposed by Hyundai Motors Corporation.

• Journal of the Optical Society of Korea
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• 제18권5호
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• pp.605-610
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• 2014

Clouds play an important role in climate change, in the prediction of local weather, and also in aviation safety when instrument assisted flying is unavailable. Presently, various ground-based instruments used for the measurements of the cloud base height or velocity. Lidar techniques are powerful and have many applications in climate studies, including the clouds' temperature measurement, the aerosol particle properties, etc. Otherwise, it is very circumscribed in cloud velocity measurements because there is no Doppler effect if the clouds move in the perpendicular direction to the laser beam path of Doppler lidar. In this paper, we present a method for the measurement of cloud velocity using lidar's range detection and DIC (Digital Image Correlation) system to overcome the disadvantage of Doppler lidar. The lidar system acquires the distance to the cloud, and the cloud images are tracked using the developed fast correlation algorithm of DIC. We acquired the velocities of clouds using the calculated distance and DIC algorithm. The measurement values had a linear distribution.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2009년도 한국우주과학회보 제18권2호
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• pp.49.3-49.3
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• 2009

Geostationary Ocean Colour Imager (GOCI) is the first ocean color instrument that will be operating in a geostationary orbit from 2010. GOCI will provide the crucial information of ocean environment around the Korean peninsula in high spatial and temporal resolutions at eight visible bands. We report an on-going development of imaging and radiometric performance prediction model for GOCI with realistic data for reflectance, transmittance, absorption, wave-front error and scattering properties for its optical elements. For performance simulation, Monte Carlo based ray tracing technique was used along the optical path starting from the Sun to the final detector plane for a fixed solar zenith angle. This was then followed by simulation of red-tide evolution detection and their radiance estimation, following the in-orbit operational sequence. The simulation results proves the GOCI flight model is capable of detecting both image and radiance originated from the key ocean phenomena including red tide. The model details and computational process are discussed with implications to other earth observation instruments.

• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2017년도 추계학술발표대회
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• pp.1258-1261
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• 2017

1급 발암물질인 미세먼지 중 44.3%를 차지하고 있는 도로 비산먼지는 효과적인 미세먼지 농도 저감 대책의 방안 중 하나이다. 도로 비산먼지 제거는 일반적으로 특수 차량을 이용, 정해진 경로와 주기에 따라 운행된다. 이러한 운행방식은 도로의 오염 현황에 따른 효과적 경로 선정 및 운영이 어렵다. 본 논문에서는 도로 비산먼지 제거의 효율적인 경로 제안을 위해 대구지역에 분포된 KISTI 이동형 도시센싱 테스트베드에서 수집되는 고해상도의 실시간 지역별 오염 현황 데이터를 활용하여 실시간 오염도를 분석하고, LSTM(LONG SHORT-TERM MEMORY) 알고리즘을 활용하여 미래의 미세먼지 농도를 예측하였다. 기존 연구와 달리 지역별 상황을 고려한 데이터를 사용하여 선형 회귀 분석을 수행하였다. 실험 결과, 시간 속성을 고려한 LSTM이 MLP 보다 평균 제곱근 오차 값이 경우에 따라 최대 30% 더 작음을 확인했다. 본 연구를 기반으로 고해상도 사물 데이터 기반 예측 연구의 가능성을 보였으며, 미세먼지 예측 결과를 활용 유연하고 효과적인 도로 청소차량의 운행 경로를 설정에 활용될 수 있을 것으로 기대한다.

• 대한간호학회지
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• 제31권4호
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• pp.681-691
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• 2001

Purpose: The exercise status in patients with rheumatoid arthritis, associations between exercise behavior and personal factors, and associations between exercise behavior and exercise-specific cognitions and their effects were assessed. Method: Four hundred thirty nine outpatients with rheumatoid arthritis were studied. The exercise status was measured by a single item. The intensity was multiplied by the frequency and duration of each exercise. The product of these intensity values for all exercises was defined as exercise behavior. Based on the Pender's revised health promotion model, exercise benefit, barrier, self-efficacy, enjoyment and social support were chosen as exercise specific cognitions and affect variables. Path analysis was used to identify the predictors of exercise behavior. Results: Compared to the duration before being diagnosed, the number of subjects who exercised regularly increased after being diagnosed. However over half of the subjects refrain from any sort of exercise and the type of exercise is very limited. Among the variables, exercise barrier, self-efficacy, and social support were found to be significant predictors of exercise behavior, and only previous exercise experience was found to be significant predictors of all behavior specific cognitions and affect variables. Conclusion: These findings suggest that studies should explore exercise behaviors and strategies to emphasize the cognitive-motivational messages to promote exercise behaviors.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2018년도 추계학술대회
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• pp.586-589
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• 2018

도로 교통 시스템에 빅데이터 기술이 융합되면서 운전자와 보행자에게 편리하고 도움이 되는 새로운 서비스들이 생겨나고 있다. 다양한 교통 데이터를 수집하고 분석함으로써 교통 시스템에서 흔히 발생할 수 있는 정체 현상 또는 교통량 등을 예측하는 모델이 개발되고 있다. 본 논문에서는 대구시에서 수집한 택시 경로 데이터를 이용하여 대구시의 지도 위에 해당 데이터를 시각화한다. 그 다음으로 대구 시 내의 도로 구간을 설정하고, 택시 데이터의 위치와 속도 데이터, 그리고 도로 구간 정보를 이용하여 해당 구간의 교통량과 구간에서의 차량 평균 속도를 구한다. 이 결과를 이용하여 특정 도로 구간에 대한 교통 시스템 문제 파악에 도움을 주고자 한다.

• 기본간호학회지
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• 제3권2호
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• pp.183-199
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• 1996

The Purpose of this study is to develop and test a nursing model which can be applied to prediction of the quality of life for the patient receiving hemodialysis. A hypothetical model was constructed on Johns & Meleis's empowerment model framework which has 3 contsructs(stress, resource, empowerment). 6 Factors(perceived stress, self-esteem as personal resource, perceived social support as social resource, perceived fertigue, perceived health status & self efficacy as empowerment) were selected to pre dict the quality of life of receiving hemodialysis patients. 4 Factors(self-esteem, perceived social support, perceived health status & self efficacy) had direct effects on the quality of life significantly. Self-esteem had indirect effect on the quality of life via perceived heath status significantly. Perceived social support had indirect effect on the quality of life via self-effcacy significantly. Perceived stress had no direct and indirect effect on the quality of life significantly. Revised model from hypothetical model showed better fit to the data by eliminating unsignificant path. From results of this study we suggest that to improve quality of life of hemodialysis patient nurses provide nursing interventions which improve self-esteem, perceived social support, self-efficacy & perceived health status.