• Transactions of the Korean Society of Mechanical Engineers B
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• v.29 no.12 s.243
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• pp.1313-1320
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• 2005

In this investigation, we studied the wake interactions incurred by two nearby spheres at Re=300. We considered all possible arrangements of the two spheres in terms of the distance between the spheres and, the angle inclined with respect to the flow direction. It turns out that significant changes in shedding characteristics are noticed depending on how the two spheres are positioned. In this study, not only quantitative changes in the key physical parameters such as force coefficients and shedding frequencies, but also qualitative changes in shedding patterns are analyzed and reported.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.4
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• pp.75-80
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• 2001

An error analysis is very important to estimate performance of a precision machine. This study proposes an error analysis for a new parallel device, a cubic parallel device. The cubic parallel manipulator has error sources including upper and lower universal joint errors due to the directional changes in the link and actuation errors. The maximum errors of the end effector are affected by the axial direction changes of each links and the clearances of the universal joints when the parallel manipulator is moving along a path. It is found that the changes of errors mostly occur at the positions where the directions of exerting link forces shift. The error analysis is based on an error model formed from the relation between the universal point errors and the end-effector accuracy. The analysis method can be also used in predicting the accuracy of other parallel devices.

• Asian Journal for Public Opinion Research
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• v.1 no.2
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• pp.147-150
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• 2014

Mixed-mode (or multi-mode) surveys and (volunteer) web panels were recently introduced as ways to cope with changes in the social survey environment, which is going through a rapid and massive transformation. The direction, speed, and magnitude of these changes have been clear in Korea, too. Enumerated in Figure 1 are the social surveys between 1960 and 2010 archived by the Korean Social Science Data Archive (KOSSDA) 2. The left panel shows the exponential growth in the overall volume. The other two panels, more importantly, show the changes in the composition. Mixed-mode and online surveys are rapidly increasing their shares and are fast becoming de facto standards in Korea, as in many other countries.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.143-144
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• 2018

It was 15 years since the remodeling system was introduced in 2001 and the remodeling system was implemented due to the amendment of the housing law. From now on, the remodeling will be settled in the direction of important apartment houses, and planning will be the core plan of remodeling. Up to now, the remodeling system has changed according to the market situation, and the planning plan has also changed based on the laws and regulations. In this background, this study summarizes the changes of the regulations related to the remodeling plan and examines the characteristics of the plan according to the changes of the regulations. The remodeling plan can be divided into three periods according to the changes of the regulations, and the contents of the regulations and the characteristics of the plan have been clarified.

• The Journal of Information Systems
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• v.7 no.1
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• pp.5-21
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• 1998

The speedy advance of network technology with axis internet gives the business opportunities to the today's firms and also makes them apply the intranet and groupware to their management. And, the firms admit these technological changes and expand the investment on the network. But, the firm's plans to cope with the changes which is caused by the appliance of the network technology to their firms are not prepared yet. Especially, the firm's managers are particularly wondering on how to use the already invested network hardware. In this article, we investigated the advance process and direction of the network technology like internet, groupware, and intranet, the firm's efforts to build network system, and the changes of the business process procedures. To apply the new technologies such as intranet and groupware into the business, the firms have to change the function of computer center from the programming to the user training and the management of network and computing resources, and they need to standardize their business process.

• International Journal of High-Rise Buildings
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• v.1 no.2
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• pp.81-85
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• 2012

Vertical meteorological conditions encountered by super tall buildings, such as wind speed, temperature and humidity, vary due to their height. Therefore, it is necessary to consider these environmental changes to properly estimate the heating and cooling loads, and to minimize the energy demands for HVAC in super tall buildings. This paper aims to analyze how vertical meteorological changes affect heating and cooling loads of super tall buildings by using numerical simulation. A radiosonde, which observes atmospheric parameters of upper air such as wind speed, wind direction, temperature, relative humidity and pressure, was used to provide weather data for the building load simulation. A hypothetical super tall building was used for the simulation to provide quantified characteristics of the heating and cooling loads, comparing the lower, middle and upper parts of the building. The effect of weather data on the heating and cooling loads in super tall building was also discussed.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.32 no.4
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• pp.79-86
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• 2009

The purpose of this paper is to analyze the 24 mail center's efficiency and productivity changes from first quarter to fourth quarter of 2008 using window analysis and Malmquist productivity index. Row views of window analysis results make it possible to determine trends and/or observed behavior with the same data set, and column views to examine the stability of results across different data sets. Malmquist productivity indexes greater than unity translate into improvements in productivity, and less than unity mean deterioration in performance over time. The results of this study suggest that DEA models under dynamic situations such as window analysis and Malmquist productivity index enable us to comprehend the efficiency and productivity changes over time and to show the direction of improvements.

• Journal of Families and Better Life
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• v.22 no.1
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• pp.77-89
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• 2004

The study examined the shift in the attitudes of college students regarding familial gender roles between 1991 to 2002. The results are as follows. (a)There were changes toward the egalitarian direction in familial-related gender role attitudes between 1991 and 2002, in both male and female college students. (b)Yet, despite of these changes toward egalitarianism, Female colleges students exhibited the more egalitarian familial gender role attitudes than their male counterparts, both in 1991 and 2002. (c)The shift toward more egalitarian attitudies was most pronounced in couples' equal participation in decision making, the sharing of housework, and women's participation in labor force. however, the shift toward egalitarian attitudies was less pronounced in the issues concerning outside home activities of the mothers with infants. Based on the results, implication for the future family and family education programs were discussed.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.11a
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• pp.128-133
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• 2007

Modern society changes so fast that it makes the borderlines obscure among all the elements in physical environments as well as culture and economy through rapid flows of Network or new media. Also these flows of changes appears and collides everywhere at the same time, which continuously generates heterogeneous environmental factors. For this reason, architecture is required to correspond with circumstances of the day, but it doesn't keep up with the speed of social changes actually because it features physically fixed construction. This research offers new direction and possibilities of architecture space elements using pluralistic and do-centering attributes of hypertext as a counterplan, and finds out how architecture space should correspond with the moving environment of modern society.

• Korean Journal of Applied Biomechanics
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• v.15 no.3
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• pp.95-104
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• 2005

To know the proper setup posture for the various clubs, changes of setup variables according to the change of golf club length was investigated. Swing motions of three male low handicappers including a professional were taken using two high-speed videocameras. Four clubs iron 7, iron 5, iron 3 and driver (wood 1) were selected for this experiment. Three dimensional motion analysis techniques were used to get the kinematical variables. Mathcad and Kwon3D motion analysis program were used to analyze the position, distance and angle data in three dimensions. The variables divided into three categories 1) position and width of anterior-posterior direction 2) position and width of lateral direction 3) angles and evaluated based on the theories of many good golf teachers. Major findings of this study were as follows. 1.The stance (distance between ankle joints) was increased as the length of the club increased but the increasing width was not large. It ranges from 5cm to 10cm and professional player showed small changes. 2. Forward lean angle of trunk was decreased (more erected) as the length of the club increased. It ranges from 30 degrees for iron7 to 25 degrees for driver. 3. Angle between horizontal and right shoulder were increased as the length of the club increased. It ranges from 10 degrees to 20 degrees and professional player showed small changes. 4. Anterior-posterior position of the shoulders were located in front of the foot for all clubs and the difference between the shoulder and knee position was decreased as the length of the club increased. 5. Anterior-posterior position of grip (hand) was located almost beneath the shoulders (2.5cm front) for iron7, but it increased to 10cm for the driver. This grip adjustment makes the height of the posture increased only 5cm from iron7 to driver. 6. Lateral position of grip located at 5cm left for the face of iron7, but it located at the right side (behind) for the face of driver. 7. Lateral position of the ball located at the 40%(15cm) of stance from left ankle for iron7 and located at the 10% (5cm) of stance for driver. 8. Head always located at the right side of the stance and the midpoint of the eyes located at the 37% of stance from the right ankle for all clubs. This means that the axis of swing always maintained consistently for all clubs. 9. Left foot opened to the target for all subject and clubs. The maximum open angle was 25 degrees. Overall result shows that the changes of the setup variables vary only small ranges from iron7 to driver. Paradoxically it could be concluded that the failure of swing result from the excessive changes of setup not from the incorrect changes. These findings will be useful for evaluating the setup motion of golf swing and helpful to most golfers.