• Korean Institute of Interior Design Journal
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• v.22 no.6
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• pp.29-39
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• 2013

Architecture has been expressed a complexity of their civilization with evolving into a living spaces and a crystalloid of culture in the times. So, architecture is always a dramatic phenomenon related to architectural aesthetic and technical expression in harmony with social and cultural issues by the times. From this point of view, we can describe that architecture is one of an important mediators to analyze the integrated trend of time. Specially an expressed building envelop which is a matter of consequence in the architectural component is first visual factor including architectural meaning and historical back ground. Therefore, this study firstly starts an investment for discriminative characteristics of building envelop design in the times, then will take the comparative analysis related with modern age and contemporary age based on phases of the times. This research will give the chance to prepare of the pillar of future envelop design in the practical affairs and has simultaneously the chance to understand of inclusive envelop design methodology by the changes of the times.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.32 no.11
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• pp.905-910
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• 2008

Vibration analysis is widely used in machinery diagnosis and the wavelet transform has also been implemented in many applications in the condition monitoring of machinery. In contrast to previous applications, this paper examines whether acoustic signal can be used effectively along vibration signal to detect the various local fault, in local fault of gearboxes using the wavelet transform. Moreover, envelop analysis is well known as useful tool for the detection of rolling element bearing fault. In this paper, a acoustic emission (AE) sensor is employed to detect gearbox damage by installing them around bearing housing at driven-end side. Signal processing is conducted by wavelet transform and enveloping to detect her fault all at once gearbox using AE signal.

• Journal of Advanced Marine Engineering and Technology
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• v.33 no.5
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• pp.672-678
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• 2009

Acoustic Emission (AE) technique is a non-destructive testing method and widely used for the early detection of faults in rotating machines in these days, because the sensitivity of AE transducers is higher than normal accelerometers. So it can detect low energy vibration signals. The faults in the rotating machines are generally occurred at bearings and gearboxes which are the principal parts of the machines. It was studied to detect the bearing faults by envelop analysis in several decade years. And the researches showed that AE had a possibility of the application in condition monitoring system(CMS) using the envelope analysis for the rolling bearing. And peak ratio (PR) was developed for expression of the bearing condition in condition monitoring system using AE. Noise level is needed to reduce to take exact PR value because the PR is calculated from total root mean square (RMS) and the harmonics peak levels of the defect frequencies of the bearing. Therefore, in this paper, the discrete wavelet transform (DWT) was added in the envelope analysis to reduce the noise level in the AE signals. And then, the PR was calculated and compared with general envelope analysis result and the result of envelope analysis added the DWT. In the experiment result about inner fault of bearing, defect frequency was difficult to find about only envelop analysis. But it's easy to find defect frequency after wavelet transform. Therefore, Envelop analysis added wavelet transform was useful method for early detection of default in signal process.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2008.11a
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• pp.43-48
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• 2008

Gear system has been widely used in industrial applications and unexpected failures of gears are not only extremely damaging but also lead to economic losses. So, early detection of fault is important for diagnosis machine condition. And acoustic emission is an efficient non destructive testing technique for the diagnosis of machine health and is useful technique for early detection of fault because it can find low-amplitude and high-frequency signal on account of high sensibility. Therefore, in this paper, the AE signal was measured and preprocessed using envelop analysis for gearbox with misalignment between pinion and gear. And then the vibration characteristic of gear misalignment was analyzed.

• Journal of the Architectural Institute of Korea Planning & Design
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• v.35 no.8
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• pp.23-34
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• 2019

The façade, a fundamental function as a skin that protects human life from external environment such as cold and hot weather, snow, rain, and wind, etc, has served as a media for communication between indoor space of the building and outside space. From the media for communication point of view, the approach to envelope design, in which environmental elements are transmitted internally through the filtering of external environments, has been evolving in various ways from the past to the present. Today, modern architecture technologies including curtain wall systems and user-friendly computer programming and environmental analysis programs demonstrate a differentiated approach to envelope design related to the indoor environment. For this reason, it is worth noting that the envelope design factors and trends that appear variously in the UNStudio's projects before and after the 2000s. The factors reflected in the envelop design in conjunction with the indoor environment obtained through the case study of the UNStudio's office projects were daylight environment, thermal environment, ventilation, noise, privacy and view, and consideration for daylight environment and thermal environment was reflected in many cases through the case study. Looking at the changes in the diagrams in order of year, it can be seen that the envelope design using the environmental analysis tool has been performed since 2006. This is a clue to show the envelop design changes from the conceptual method to the data-based one. The diagrams and analysis results related to the envelop design showed that the thermal environment related to solar radiation was the most, and no diagrams and analysis related to the indoor illumination were found. Since 2010, PV panel installation has been shown in the envelope design, which can be found in the increased efficiency of PV panels due to the technological advances and the decrease in production cost.

• Journal of Society of Preventive Korean Medicine
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• v.17 no.3
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• pp.103-114
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• 2013

Objectives : This study aimed to analyze the management efficiency of Korean Medicine hospitals for recent 10 years(2001~2010) using the Data Envelop Analysis(DEA) model. Methods : We collected the management data of 23 Korean Medicine hospitals for DEA model from the Korean Oriental Medicine Hospitals' Association (KOMHA). Input variables of DEA model are numbers of beds, numbers of doctors, numbers of nurses and numbers of other staffs of each Korean Medicine hospitals. Output variables are numbers of inpatients and numbers of outpatients of each Korean Medicine hospitals. Based on the DEA model, we calculated the efficiency score of each Korean Medicine hospital and compared it by hospital's ownership, location, and size. Results : Average DEA efficiency scores of Korean Medicine hospitals by year ranged from 0.86 to 0.92. Private owned hospitals showed higher efficiency scores than the university affiliated hospitals with statistical significance (p=0.001). And Korean Medicine hospitals located in capital region of Korea(Seoul City, Incheon City, Gyeonggi-do) and the rest Korean Medicine hospitals did not show statistical difference (p=0.516). Lastly, Korean Medicine hospitals with different size did not show statistical difference in management efficiency (p=0.499). Conclusion : We have found that Korean Medicine hospitals management efficiency have not changed throughout 10 years, and that different ownership forms of Korean Medicine hospital show statistical difference in management efficiency while location, and size do not.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.6
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• pp.40-52
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• 1998

A good grasp of the failure mechanisms of resistance spot weld, widely used in joining the auto-panels, in essential to the structural/crashworthy analyses and integrity assessment of the whole auto-body. In this study, We provide an estimative model describing the failure behavior of resistance spotf weld, and apply the model to the finite element analysis of crashworthiness. First, in "Part 1-Failure Criteria", to be used for the finite element analysis of spot-welded structural panels of an auto-body, (i) a methodology for quantifying the spot weld failure and the accompanying failure criteria are presented, and (ii) the coefficients of the failure equation are determined by a munimum number of appropriate experimental tests. To achieve these, we derive the functional form of the failure envelop by limit analysis, and correlate it with the form in PAM-$CRASH^{TM}$ code, and also investigate the effect of the failure coefficients on the failure envelop form. An estimative model obtained in this Part1, as spot weld failure criteria is applied to the Macroscopic finite element analysis of autobody structural panels using PAM-$CRASH^{TM}$ code in Part 2.

• International Journal of Air-Conditioning and Refrigeration
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• v.9 no.1
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• pp.71-76
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• 2001

Factors governing the rate of heat exchange comprise temperature, air velocity, relative humidity, and relation indoors. Recently, there are many researches on the transient analysis of indoor environmental factors such as dry bulb temperature, relative humidity and air velocity in miniature models. The purpose of this study is to measure the environmental factors and to analyze and evaluate the characteristics of indoor environment in different envelop structures using granite dome models. The interior relative humidity is constant regardless of exterior humidity although a little range of variation is shown in comparison to the cement model.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2009.04a
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• pp.109-110
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• 2009

• Proceedings of the Korean Geotechical Society Conference
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• 1997.11a
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• pp.21-30
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• 1997