• Journal of computational fluids engineering
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• v.19 no.3
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• pp.44-51
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• 2014

Considering the importance of the detailed resolution of the reacting flow field inside a gasifier, the objective of this study lies on to investigate the effect of important variables to influence on the reacting flow and thereby to clarify the physical feature occurring inside the gasifier using a comprehensive gasifier computer program. Thus, in this study the gasification process of a 1.0 ton/day gasifier are numerically modeled using the Fluent code. And parametric investigation has been made in terms of swirl intensity and aspect ratio of the gasifier. Doing this, special attention is given on the detailed change of the reacting flow field inside a gasifier especially with the change of this kind of design and operation parameters. Based on this study, a number of useful conclusions can be drawn in the view of flow pattern inside gasifier together with the consequence of the gasification process caused by the change of the flow pattern. Especially, swirl effect gives rise to a feature of a central delayed recirculation zone, which is different from the typical strong central recirculation appeared near the inlet nozzle. The delayed feature of central recirculation appearance could be explained by the increased axial momentum due to the substantial amount of the presence of the coal slurry occupying over the entire gasifier in gasification process. Further, the changes of flow pattern are explained in detail with the gasifier aspect ratio. In general, the results obtained are physically acceptable in parametric study.

• Journal of architectural history
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• v.27 no.2
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• pp.101-112
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• 2018

The study on the government office building in Chungcheong Suyeong(忠淸水營) is very rare. How were the Gaeksa(客舍) and Dongheon(東軒) which are representative government office buildings in Suyeong, maintained and what was the aspect of it, while passing through the upheaval period of the end of Joseon(朝鮮)? And where was the original place and was there any change in use? It is so regrettable that these subjects were not figured out yet. So I thought it is very important task to figure out its actual aspect by investigating the maintain state of the Gaeksa and Dongheon and the change of their places. So this study examined the related historical records and, based on it, analyzed "Ocheon GoonJi(鰲川郡誌)" in various view points. Through this analysis, this study could figured out the maintain aspect of the gaeksa and dongheon and the change of their places, and be able to deduce the other change of the government office building. This study could assume the places of each government office buildings by comparing this investigated result and the analyzed result of the original cadastral map in various view points. As the result of the study done by this method, this study confirmed the maintain state of the Gaeksa and Dongheon in Chungcheong Suyeong while passing through the upheaval period of the end of Joseon. And this study figured out the places of the Gaeksa and Dongheon, and be able to confirm their places by the lot number on the original cadastral map. Along with this, this study could estimate Jo(趙) family's confliction with the residents at that time by verifying the lot numbers of the Sapaeji(賜牌地) which this family received from the government. And among the names of the government office buildings, for the Jangkyocheong(將校廳) which is in dispute because of the name, this study figured out that the author of "Ocheon GoonJi" made a mistake in writing Dongheon.

• The Journal of the Acoustical Society of Korea
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• v.40 no.4
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• pp.330-336
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• 2021

In bistatic sonar operation, the scattering strength of a sonar target is characterized by the probe signal frequency, the aspect angle and the bistatic angle. Therefore, the target detection and identification performance of the bistatic sonar may vary depending on how the positions of the target, sound source, and receiver are changed during sonar operation. In this study, it was evaluated which variable is advantageous to change by comparing the target identification performance between the case of changing the aspect angle and the case of changing the bistatic angle during the operation. A scenario of identifying a hollow sphere and a cylinder was assumed, and performance was compared by classifying two targets with a support vector machine and comparing their accuracy using a finite element method-based acoustic scattering simulation. As a result of comparison, using the scattering strength defined by the frequency and the bistatic angle with the aspect angle fixed showed superior average classification accuracy. It means that moving the receiver to change the bistatic angle is more effective than moving the sound source to change the aspect angle for target identification.

• Journal of the Korean Society of Clothing and Textiles
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• v.34 no.11
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• pp.1812-1823
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• 2010

The modifiable design of clothes is significant in that a single garment can be presented in various ways and can be modified by user adjustments as well different kinds of figurative beauty can be expressed through the garment. This study departmentalized the case of knitwear in the modifiable design of clothes to propose a possibility of a variable knit fashion that makes the most of the knit characteristics. This study investigated precedent research, arranged general terms, created fundamental notions, found the background of the advent, and located specific characters in the modifiable design as well as arranged a concept, type, structure, and traits for the knit. The following results were obtained through this study. First, the modifiable design of the clothes can express the change of the silhouette and the change of the item itself or a change in the item according to the change in the mode of wearing, manipulation, and technology. Second, the results show that modifiable knit designs by open & close are mostly used according to manipulation and have no existence in this study according to the technology. Third, there was a noticeable appearance of a modifiable knit design from 2002 to 2004. However, it was increased again in 2009 after a steady decrease in 2005 and 2008. Finally, it can create effects in several dresses in the visual aspect and functional aspect.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.22 no.1
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• pp.53-60
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• 2012

To reduce the vibration in industrial settings, the viscous fluid dampers have been widely used. Since the damper shows a viscoelastic behavior, many methods to predict the behavior have been investigated. But the methods did not consider a change of damper size that is important factor for practical design engineer. In this study, to predict a change of damper ability with respect to a change of damper size, the dynamic experiment were conducted with fixed aspect ratio and gap. The damping coefficient at zero frequency was computed through theoretical and experiment approach in order to fit the experimental results using fractional derivative Maxwell model.

• 유체기계공업학회:학술대회논문집
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• 2006.08a
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• pp.217-220
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• 2006

The lift and drag forces produced by a wing of a given cross-sectional profile are dependent on the wing planform and the angle of attack. Aspect ratio is the ratio of the wing span to the average chord. For conventional fixed wing aircrafts, high aspect ratio wings produce a higher lift to drag ratio than low ones for flight at subsonic speeds. Therefore, high aspect ratio wings are used on aircraft intended for long endurance. However, birds and insects flap their wings to fly in the air and they can change their wing motions. Their wing motions are made up of translation and rotation. Therefore, we tested flapping motions with parameters which affect rotational motion such as the angle of attack and the wing beat frequency. The half elliptic shaped wings were designed with the variation of aspect ratio from 4 to 11. The flapping device was operated in the water to reduce the wing beat frequency according to Reynolds similarity. In this study, the aerodynamic forces, the time-averaged force coefficients and the lift to drag ratio were measured at Reynolds number 15,000 to explore the aerodynamic characteristics with the variation of aspect ratio. The maximum lift coefficient was turned up at AR=8. The mean drag coefficients were almost same values at angle of attack from $10^{\circ}$ to $40^{\circ}$ regardless of aspect ratio, and the mean drag coefficients above angle of attack $50^{\circ}$ were decreased according to the increase of aspect ratio. For flapping motion the maximum mean lift to drag ratio appeared at AR=8.

• The KIPS Transactions:PartD
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• v.13D no.4 s.107
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• pp.593-602
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• 2006

Software development methodology has been developed for satisfying goals of improvement in productivity and reduction in time-to-market through the reuse of software assets. The current methods that implement software product-line, one of software development methodologies, interfere massively with the core assets, which require high cost in assembly level reducing the effectiveness. In this paper, we introduce Aspect-Oriented Programming (AOP) as a method for improving assembly process in software product-line. The method that assembles core assets and variabilities is described by grammar elements such as Join point, pointcut and advice without code-change. We analyze requirements of a mini-system as an example adapting AOP and design using UML. Our study implements the variabilities, which are from design stage, using an Aspect-Oriented Programming Language, AspectJ and prove usability and practicality by implementing the proposed idea using an Aspect-Oriented Programming Language, AspectJ.

• Korean Journal of Psychosomatic Medicine
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• v.9 no.1
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• pp.66-80
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• 2001

Most people experience stress during his or her life. The types of psychosocial stressors are variable. Also, the stress appraisal, coping, and responses in stress process are variable. These varieties reflect individual differences due to ongoing social situation, personal dispositions such as personal resources and vulnerability factors, etc. The stress process results in psychosocial growth or no substantial change in functioning or health, or adverse change in functioning(illness) or health to person. Therefore, the preventive management and treatment of stress need to be tailored to individual characteristics. All physicians managing the stress-related patients have to understand the multidimensional aspects of stress. To understand stress better in psychosocial aspect, I comprehensively reviewed the literature on stress.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.19 no.2
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• pp.235-240
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• 2010

The recent trend of vehicle design aims at crash safety and environmentally-friendly aspect. For the crash safety aspect, energy absorbing members should be absorbed with collision energy sufficiently. But vehicle structure must be light weight for the environmentally-friendly aspect, in order to improve fuel efficiency and to reduce tail gas emission. Therefore, the light weight of vehicle must be achieved in a status of securing safety of crash. An aluminum or CFRP (Carbon Fiber Reinforced Plastics) is representative one among the light-weight materials. In this study, impact collapse behavior of circular hybrid thin-walled member is evaluated. The hybrid members are manufactured by wrapping CFRP prepreg sheets outside the aluminum circular members in the autoclave. Because the CFRP is an anisotropic material whose mechanical properties change with its stacking condition, special attention is given to the effects of the stacking condition on the collapse behavior evaluation of the hybrid thin-walled member. Collapse mode and energy absorption capability of the hybrid thin-walled member are analyzed with change of the fiber orientation angle and interface number.

• Journal of the Korean housing association
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• v.17 no.2
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• pp.117-124
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• 2006

Korean urban traditional housing abandoned by the social apathy promptly disappearing form our sight, or ruining. It tells that the strategies we are using today are impossible to fulfill socio-economic needs of residents here. So it needed to find out the strategies which can change this place better to live in. Consolidating the street parking lots fer cars can be one of the important solutions to the area. By using cul-de-sac, after setting up small unit of communities, we will have chance to have a small public space, and at the same time it can help to set up our tradition of people's intimacy inside the community. Most people have their own cars, and the need of parking lots becomes more serious. So, a meeting place like public well in the past must replace parking lots. On the other hand, it is important to re-consolidate existing land to obtain appropriate land size for other uses. Today, the use of private space (house, private lots, etc..)and public space(streets, local offices) is very important. NIMBY (Not In My Back Yard) attitude should also be reconsidered. All these negative social aspects come from negative social relationship, thus we should consider them with care and deep understandings. The traditional housing of Korea should not be abandoned as slum, but this should be transformed in terms of the conservation since it is superior in its ecological and energy conservation aspect.