• 대한기계학회논문집
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• 제19권3호
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• pp.834-845
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• 1995

An experimental study is made in a nearly two-dimensional 90.deg. curved duct to investigate the effects of interaction between streamline curvature and mean strain on turbulence. The initial shear at the entrance to the curved duct is varied by an upstream shear generator to produce five different shear conditions ; a uniform flow (UF), a positive weak shear (PW), a positive strong shear(PS), a negative weak shear (NW) and a negative strong shear(NS). With the mean field data of the case UF, variations of the momentum thickness, the shape factor and the skin friction over the convex(inner) surface and the concave (outer) surface are scrutinized quantitatively in-depth. It is found that, while the pressure loss due to curvature is insensitive to the inlet shear rates, the distributions of wall static pressure along both convex and concave surfaces are much influenced by the inlet shear rates.

• International Journal of Precision Engineering and Manufacturing
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• 제9권3호
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• pp.68-71
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• 2008

Transdermal and topical drug delivery with minimal tissue damage has been an area of vigorous research for a number of years. Our research team has initiated the development of an effective method for delivering drug particles across the skin (transdermal) for systemic circulation, and to localized (topical) areas. The device consists of a micro particle acceleration system based on laser ablation that can be integrated with endoscopic surgical techniques. A layer of micro particles is deposited on the surface of a thin metal foil. The rear side of the foil is irradiated with a laser beam, which generates a shockwave that travels through the foil. When the shockwave reaches the end of the foil, it is reflected as an expansion wave and causes instantaneous deformation of the foil in the opposite direction. Due to this sudden deformation, the microparticles are ejected from the foil at very high speeds, and therefore have sufficient momentum to penetrate soft body tissues. We have demonstrated this by successfully delivering cobalt particles $3\;{\mu}m$ in diameter into gelatin models that represent soft tissue with remarkable penetration depth.

• 건축역사연구
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• 제14권1호
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• pp.107-122
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• 2005

The purpose of this study is to analyse Herzog & de Meuron's surface, which represents contemporary architectural trends toward surface. Semper's Bekleidung theory and the important architectural theories about surface were compared according to the conceptual opposition between representation and re-presentation, which is borrowed from Kastern Harris, and again Martin Heidegger. Representation means a sort of translation into a different medium. It doesn't preserve the material identity of what it represent. Re-presentation, however, celebrates the material employed. The tension between representation and re-presentation have activated the architectural history Contemporary architects have emphasized re-presentation at the expense of representation. This trends relate with digital technology, which demands surface or skin independent from depth or interior. Buildings that deserve to be called works of architecture invite us to attend to material in a different way Re-presenting its materials, the work of architecture reveals its being. Such revelation requires that materials work in a way that invites us to step back from our usual involvement with things. It's the poetics of re-presentation, which is emboded in the Herzog & de Meuron's architectural works.

• 한국주거학회논문집
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• 제27권5호
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• pp.73-81
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• 2016

Focused on developing form of Western architecture, invisible elements covering actual human life has been dealt with separately and the time was turned away and disparaged. But now the phenomenology, arranging such a meeting of space and time, gives opportunity to look at the actual life in architecture. Recently, Guille Deleuze and Merleau-Ponty tried to recover the sense of touch segregated in skin from body keeping eyes for distance. And the activity can be happened by being connected to the body rather than to eye in the space. From the phase of recognition where the human body tries to identify the object in the space considering a time, it will be changed for the subject to the phase of space-time structure. If the tactility is to erase the distance different from the visuality in dichotomy, it will be occurred to having a tension and makes new relationship to work trying to move the subjective point of view in object. Like this evidence in analysis of architecture, it can be found these in the Korean traditional architecture rather than Western architecture in terms of emphasizing the time and space. And this study will be intensive to the side of the Phenomenology how it is being connected to the movement in the space and time for the subject and object.

• 한국실내디자인학회논문집
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• 제20권4호
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• pp.11-20
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• 2011

Jeju Special Self-Governing Province are trying every effort to be presented as an International Free City with unique combination of history, culture and landscape, This research focuses on the analysis of characteristics we can find in buildings in Jeju province. The main purpose is to provide basic and informative materials for the landscape formation of Jeju by investigating current status of buildings in Jeju province. This research divides Jeju province into 34 areas and categorizes buildings by use. 2,973 cases in total are collected and analyzed their architectural features. A basic analysis of the collected data is conducted in the first and the second stages. And In the third stage, 505 cases whose addresses can be identified are selected for the in-depth analysis of the registered building data on architecture year, building area, and total area. These data are analyzed by the categories of region, year, and size for the study of general characteristics of buildings in Jeju. The results show that territoriality is weak because of the simplicity of building layout on the streets. Exterior form of buildings, streetscape image, and overall city image are tedious and boring because of the lack of the variety of facade and exterior finishing materials.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.234.1-234.1
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• 2014

Many studies have been investigated on high density plasma source (Electron Cyclotron Resonance[ECR], Inductively Coupled Plasma[ICP], Helicon plasma) for large area source after It is announced that productivity of plasma process depends on plasma density. Among them, Some researchers have been studied on multiple sources In this study, we attempted to determine the possibility of multiple inductively coupled plasma (ICP), and helicon plasma sources for large-area processes. Experiments were performed with the one and two coils to measure plasma and electrical parameters, and a circuit simulation was performed to measure the current at each coil in the 2-coil experiment. Based on the result, we could determine the possibility of multiple ICP sources due to a direct change of impedance due to current and saturation of impedance due to the skin-depth effect. However, a helicon plasma source is difficult to adapt to the multiple sources due to the consistent change of real impedance due to mode transition and the low uniformity of the B-field confinement. As a result, it is expected that ICP can be adapted to multiple source for large-area processes.

• KIEAE Journal
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• 제11권6호
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• pp.139-149
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• 2011

This study focuses on design tendencies in office buildings of public institutions after tightening up Korea's building energy performance criteria. Important office design criteria and recommendations pay attention to the issues such as building orientation, greening buildings, building form, space and envelop by intensifying building energy performance related laws, government guidelines and evaluation systems. The design tendencies explored in this research are as follows. Office buildings mainly face south and have various types of indoor and roof green spaces not for ecological reasons but for the rest. Building depth becomes thinner and atria are inserted into office buildings to improve daylighting and natural ventilation. Building cores are located on north or west and east sides acting as buffer spaces to reduce heat loss and to block solar radiation. Office building envelop design includes various creative ideas to control or utilize solar energy as like three dimensional or double structured skin and window size variation to cope with the intensity of solar radiation. Further, solar energy generation systems are integrated with building component such as roofs, sun screens and windows. This study demonstrates that government's reinforcement of the building energy performance criteria drives the change in design methods and approach.

• 한국분말재료학회지
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• 제14권5호
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• pp.303-308
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• 2007

The oxidation of $Fe_{73}Si_{16}B_7Nb_3Cu_1$ nanocrystalline powder has been conducted to investigate its influence on the electromagnetic wave absorption characteristics of the soft magnetic material. Oxidation occurred primarily on the surface of nanocrystals. Oxidation reduced the real part of complex permeability due to the reduction of the relative volume of the powder, which otherwise contributes to the permeability. Oxidation reduced the absorption efficiency of the sheet at frequencies over 1GHz, indicating that the relative contribution of skin depth increments to the absorption was not significant. The pulverization and milling process lowered the optimum crystallization temperature of the material by $40{\sim}50^{\circ}C$ because of the internal energy accumulated during the fragmentation and powder thinning processes.

• 대한임상검사과학회지
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• 제36권2호
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• pp.193-198
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• 2004

PET/CT combines the functional information from a positron emission tomography (PET) exam with the anatomical information from a computed tomography (CT) exam into one single exam. A CT scan uses a combination of x-rays and computers to give the radiologist a non-invasive way to see inside your body. One advantage of CT is its ability to rapidly acquire two-dimensional pictures of your anatomy. Using a computer these 2-D images can be presented in 3-D for in-depth clinical evaluation. A PET scan detects changes in the cellular function - how your cells are utilizing nutrients like sugar and oxygen. Since these functional changes take place before physical changes occur, PET can provide information that enables your physician to make an early diagnosis. The PET exam pinpoints metabolic activity in cells and the CT exam provides an anatomical reference. When these two scans are fused together, your physician can view metabolic changes in the proper anatomical context of your body. PET/CT offers significant advantages including more accurate localization of functional abnormalities, and the distinction of pathological from normal physiological uptake, and improvements in monitoring treatment. A PET/CT scan allows physicians to measure the body's abnormal molecular cell activity to detect cancer (such as breast cancer, lung cancer, colorectal cancer, lymphoma, melanoma and other skin cancers), brain disorders (such as Alzheimer's disease, Parkinson's disease, and epilepsy), and heart disease (such as coronary artery disease).

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 세계 도시지반공학 심포지엄
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• pp.899-904
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• 2009

This paper presents the analysis result of load-transfer mechanism and pile movements associated with the development of frictional resistance to understand the engineering characteristics of micropile behavior. An field load tests were performed for two different types of micropiles and they are (i) thread bar reinforcement with D=50mm and (ii) hollow steel pipe reinforcement with $D_{out}$=82.5mm and $D_{in}$=60.5mm and wrapped with woven geotextile for post-grouting. The load test results indicated that micropiling with pressured grouting provided better load-transfer characteristics than micropiling with gravity grouting under both compressive and tensile loading conditions in that unit skin frictional resistance is well distributed along installation depth. The unit weight and unconfined compressive strength of cured grout were obtained for each piling method. The strength and unit weight of micropile with pressured grouting was higher than those with gravity grouting. The fact that load bearing quality with pressured grouting is better than that of gravity grouting could be attributed to the dense mutual adhesion between surrounding ground and pile due to pressurized grouting method and better grout quality.