• 대한건축학회논문집:계획계
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• 제36권5호
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• pp.33-40
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• 2020

The purpose of this research is to provide the basic information for the development of dental healthcare system's expertise and spatial composition in diverse dental spaces in Korea according to dental specialist system enforcement. Literature review of dental expertise especially dental specialist system and investigation on current status of spatial composition of dental spaces have been conducted. After the review, the spatial composition with field survey and architectural drawings of selected dental spaces have been analyzed. The result of this study is arranged with three points. First of all, the main clinical dental spaces are the dental school's dental hospital, dental department in medical center/hospital and private dental clinic in Korea. The second one is that dental school's dental hospital had differentiated to 10-11 departments in 1970-1980's and dental department in medical center/hospital has been changing to dental hospital with 5-7 departments in 2010's, and dental clinic is changing to specific dental clinic according to dental specialist system in 2018. The third one is that spatial composition is related with dental expertise at diverse levels. Spatial composition in dental school's dental hospital had been highly differentiated with dental expertise, dental department in medical center/hospital is partially subdivided with dental specialist system, but that of dental clinic is not changed according to dental specialist system. In addition to current spatial composition according to dental expertise, it is necessary to analyze the change of spatial composition with diachronic methods to develop the dental healthcare system.

• 한국전통조경학회지
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• 제29권4호
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• pp.148-158
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• 2011

경주 월성은 신라시대 궁궐이 있었던 역사적 상징성이 있는 궁궐터로 왕경 경주의 대표적인 역사유적이다. 본 연구는 경주 월성을 대상지로 역사공간 이미지와 관광객들의 이용행태에 대한 조사를 실시하였다. 연구방법은 주로 현장조사와 설문조사 두 단계로 실시하여 수집된 데이터를 행태, 시간, 공간별로 분석했다. 연구결과는 경주 월성의 주된 이용행태는 서서 하는 행위, 앉아서 하는 행위, 놀이/유흥 순으로 나타나고, 일반적인 역사문화유적지와 비교해 이용행태는 매우 단조로운 것을 알 수 있다. 경주 월성의 이용활성화를 위하여 주 진입로의 역할기능을 강화하면서 탐방객들을 월성 내 타 공간으로 분산시키기 위하여 각 동선코스를 사전에 안내하는 표지판, 야간조명, 식생정비, 도로정비 등을 필요하다.

• Bulletin of the Korean Chemical Society
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• 제11권4호
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• pp.276-281
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• 1990

The equivalent conductance of univalent cation (potassium, silver, thallium and ammonium) perchlorates in methanol containing 18-membered crown ethers, 18-crown-6 (18C6) and 1,10-dithia-18-crown-6 (DT18C6) were measured at different temperatures. The equivalent conductances of ammonium perchlorate were increased by increasing content of DT18C6 exceptionally, due to more favorable solvations than complexations. From the equivalent conductance changes, the formation constants for 1:1 compmlexes have been determined, and the values of enthalpy and entropy changes have been calculated. The complexations of 18C6 and DT18C6 with the univalent cations under investigation are all exothermic and the ${\Delta}$S values are all negative and no considerable differences around 50 J/ (k mol). The selectivity order of 18C6 is $K^+ > Tl^+ > Ag^+ > NH_4^+$, while that of DT18C6 is $Ag^+ > Tl^+ > NH_4^+ > K^+$. By sulfur substitutions in 18C6 result in significant decrease in stability, but the stability of $Ag^+$-DT18C6 complex are $10^4$ times larger than those of $K^+$. This increase of stabilities for $Ag^+$-DT18C6 complex are primary due to the result of favorable exothermic heat of reaction between the polarizable soft cation and soft sulfur centers. In NMR experiment, the stepwise additions of cation perchlorates into crown ether solutions induced two major spectral changes. First, the resonance all shift down field and the cation induced shifts were linear up to 1:1 cation/crown ratio, above which no further changes were observed. On the basis of these results, it could be concluded that 1:1 complex is formed. Second, the magnitudes of cation induced shifts were different each other in same ligand. By addition of silver ion to the solution of DT18C6, the largest shift of proton peak near the sulfur atom was observed. These effects are also arisen from the results of covalent bonding between "soft-soft" interactions.

• 식품과학과 산업
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• 제49권4호
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• pp.64-69
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• 2016

The potentialities of 3D printing technology are discussed from technical and research-oriented perspectives for industrial manufacturing of a variety of food products. Currently, 3D printing technology has advanced to enable us to process or cook innovative foods. However, food-based materials for 3D printing are still limited in terms of eating qualities, nutritional values and functionality as well as industrial production. Therefore, this uprising issue on alternative food processing techniques especially focused on the exploration of new food materials combined with these 3D printing technologies needs to be re-spotlighted, and then solved to pave the way to this innovative and sensational area of investigation with more accessibility. In this review, previous research work and industrial applications conducted by frontier research groups in this field are covered, then to open discussion for future research on the 3D printing of food.

• 정보보호학회논문지
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• 제21권6호
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• pp.55-65
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• 2011

최근 유무선 통신 네트워크의 확산 및 고속화에 따라 인터넷 기술을 활용한 높은 수준의 확장성을 제공하는 클라우드 컴퓨팅 서비스(Cloud Computing Service) 이용이 증가하고 있다. 클라우드 컴퓨팅 서비스란 네트워크, 서버, 스토리지, 응용프로그램 등 다양한 컴퓨팅 자원들의 공유된 풀에 네트워크로 접근하여 언제든지 편리하게 사용 가능한 컴퓨팅 방식으로써 컴퓨팅 환경의 가상화라는 클라우드 컴퓨팅 서비스의 본질적인 특성으로 인해 디지털 포렌식 관점에서 사건 수사 시 데이터를 확보하는 일 자체가 어려운 현실에 직면했다. 본 논문에서는 클라우드 컴퓨팅 서비스에 대한 디지털 포렌식 관점의 연구와 IaaS 형태의 클라우드 컴퓨팅서비스 중 시장 점유율의 대부분을 차지하고 있는 AWS(Amazon Web Service)와 Rackspace에 대한 증거데이터 수집 및 분석방안을 제시한다.

• Structural Engineering and Mechanics
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• 제77권3호
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• pp.343-354
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• 2021

The frequencies formulas of the bridge are of great importance in the design process since these formulas provide insight dynamic characteristics of the structure, which guides the designers to parametric analyses and the layout of the bridge in conceptual or preliminary design. Continuous rigid frame bridge is popular in the mountainous area. Mostly, this type of bridge was simplified either as a girder or cantilever when calculating the frequency, however, studies showed that the different configuration of the bridge made the problem more complex, and there is no unified fundamental calculation pattern for this kind of bridge. In this study, an empirical frequency equation is proposed as a function of pier's height, stiffness of pier and the weight of the structure. A unified fundamental frequency formula is presented based on the energy principle, then the typical continuous rigid frame bridge is investigated by finite element method (FEM) to study the dynamic characteristics of the structure, and then several key parameters are investigated on the effect of structural frequency. These parameters include the number, position and stiffness of the tie beam. Nonlinear regression analyses are conducted with a comprehensive statistical study from plenty of engineering structures. Finally, the proposed frequency equation is validated by field test results. The results show that the fundamental frequency of the continuous rigid frame bridge increases more than 15% when the tie beams are set, and it increases with the stiffness ratio of tie beam to pier. The results also show that the presented unified fundamental frequency has an error of 4.6% compared with the measured results. The investigation can predicate the approximate longitudinal fundamental frequency of continuous ridged frame bridge, which can provide reference for the seismic response and dynamic impact factor design of the pier.

• 한국의류학회지
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• 제45권3호
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• pp.409-422
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• 2021

A doctor's coat worn by Seo Jae-pil (1864-1951)-National Registered Cultural Heritage No. 607-was conserved with wet cleaning to remove thick wrinkles and brown stains that had been present for a long time. This paper also applied microscopic observation and infrared spectrophotometric analysis to obtain scientific investigation data on the cotton fabric of this doctor's coat. Information about Seo Jae-pil's time as a doctor, the process of changing his English name, and C.D.Williams & Co., which produced the medical coat, revealed that this doctor's coat was worn by Seo Jae-pil between 1892 and 1898 or 1926 and 1939. Additionally, this paper proposes a pad for filling relics that can protect the shape of modern and contemporary clothing, such as Seo Jae-pil's doctor's coat, for display at a museum site. Specifically, this research provides detailed information on the manufacturing of filling pads that can prevent damage to modern and contemporary jackets and coats so that they can be used in the cultural heritage field by developing filling materials for three-dimensional costume artifacts.

• Steel and Composite Structures
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• 제39권1호
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• pp.95-107
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• 2021

In this work, the dynamic response of functionally graded beams on variable elastic foundations is studied using a novel higher-order shear deformation theory (HSDT). Unlike the conventional HSDT, the present one has a new displacement field which introduces undetermined integral variables. The FG beams were assumed to be supported on Winkler-Pasternak type foundations in which the Winkler modulus is supposed to be variable in the length of the beam. The variable rigidity of the elastic foundation is assumed to be linear, parabolic and sinusoidal along the length of the beam. The material properties of the FG porous beam vary according to a power law distribution in terms of the volume fraction of the constituents. The equations of motion are determined using the virtual working principle. For the analytical solution, Navier method is used to solve the governing equations for simply supported porous FG beams. Numerical results of the present theory for the free vibration of FG beams resting on elastic foundations are presented and compared to existing solutions in the literature. A parametric study will be detailed to investigate the effects of several parameters such as gradient index, thickness ratio, porosity factor and foundation parameters on the frequency response of porous FG beams.

• Structural Engineering and Mechanics
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• 제77권4호
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• pp.441-461
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• 2021

Reinforced concrete (RC) columns are crucial in building structures and they are of higher vulnerability to terrorist threat than any other structural elements. Thus it is of great interest and necessity to achieve a comprehensive understanding of the possible responses of RC columns when exposed to high intensive blast loads. The primary objective of this study is to derive analytical formulas to assess vulnerability of RC columns using an advanced numerical modelling approach. This investigation is necessary as the effect of blast loads would be minimal to the RC structure if the explosive charge is located at the safe standoff distance from the main columns in the building and therefore minimizes the chance of disastrous collapse of the RC columns. In the current research, finite element model is developed for RC columns using LS-DYNA program that includes a comprehensive discussion of the material models, element formulation, boundary condition and loading methods. Numerical model is validated to aid in the study of RC column testing against the explosion field test results. Residual capacity of RC column is selected as damage criteria. Intensive investigations using Arbitrary Lagrangian Eulerian (ALE) methodology are then implemented to evaluate the influence of scaled distance, column dimension, concrete and steel reinforcement properties and axial load index on the vulnerability of RC columns. The generated empirical formulae can be used by the designers to predict a damage degree of new column design when consider explosive loads. With an extensive knowledge on the vulnerability assessment of RC structures under blast explosion, advancement to the convention design of structural elements can be achieved to improve the column survivability, while reducing the lethality of explosive attack and in turn providing a safer environment for the public.

• 한국의류산업학회지
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• 제22권6호
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• pp.844-852
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• 2020

This study is to understand the preferences of pilots, flight engineers and crew who work in the same aircraft but are exposed to different working environments and perform different mission operations in order to develop an ergonomic flight jacket. Based on a preliminary investigation, a survey of 107 pilots and 36 flight engineers and crew was conducted. The results are as follows; Pilots can control the temperature inside the cockpit, so they are less exposed to the cold when working, while flight engineers and crew are exposed to the cold more because they have many external tasks. The reason for the problem of the current flight jacket was a difference in ranking between two groups, but the highest ranking was poor dimensional suitability due to the habit of wearing layers of clothing. As a result of preferred design, there were significant differences between groups in the item of overall style. Pilots preferred a bomber jacket style(P:68.2%, E&C:44.4%), on the other hand, flight engineers and crew preferred a field jacket style(P:26.2%, E&C:55.6%)(p<.01). They preferred a stand collar(P:71.0%, E&C:86.1%), a fastener slider for a front fastening(P:62.6%, E&C:61.1%), fastener tape cuffs(P:54.2%, E&C:47.2%), a jacket with a softshell(P:86.9%, E&C:83.3%), fleece as softshell material(P:88.8%, E&C:69.4%), and fastener sliders as a attaching method(P:69.2%, E&C:61.1%). A hem fastening will be selected differently according to the overall style of outshell. Additionally, they preferred more than 5ea pockets(P:51.4%, E&C:44.4%), fastener sliders as pocket's fastenings(P:48.6%, E&C:61.1%), armpit ventilations(P:62.9%, E&C:58.5%). The results of above will be considered to design an ergonomic flight jacket.