The objective of this study was to investigate design factors of the electrolysis reactor through the CFD(computational fluid dynamics) simulation technique. Analyses of velocity vector, streamline, chloride ion concentration distribution showed differences in flow characteristics between the plate type electrode and the porous plate type electrode. In case of the porous plate type electrode, chlorine gas bubbles generated from the anode made upward density flow with relatively constant velocity vectors. Electrolysis effect was more expected with the porous plate type electrode from the distribution of chloride ion concentration. The upper part of the electrolysis reactor with the porous plate type electrode had comparatively low chloride concentration because chloride was converted to the chlorine gas formation. Decreasing the size and increasing total area of rectifying holes in the upper part of cathodes, and widening the area of the rectifying holes in the lower part of cathodes could improve the circulation flow and the efficiency of electrolysis reactor.

This paper is concerned with the numerical analysis of dynamic response of floating offshore wind turbine subject to underwater explosion using an effective non-reflecting technique. An infinite sea water domain was truncated into a finite domain, and the non-reflecting technique called the perfectly matched layer(PML) was applied to the boundary of truncated finite domain to absorb the inherent reflection of out-going impact wave at the boundary. The generalized transport equations that govern the inviscid compressible water flow was split into three PML equations by introducing the direction-wise absorption coefficients and state variables. The fluid-structure interaction problem that is composed of the wind turbine and the sea water flow was solved by the iterative coupled Eulerian FVM and Largangian FEM. And, the explosion-induced hydrodynamic pressure was calculated by JWL(Jones-Wilkins-Lee) equation of state. Through the numerical experiment, the hydrodynamic pressure and the structural dynamic response were investigated. It has been confirmed that the case using PML technique provides more reliable numerical results than the case without using PML technique.

This study was conducted to test the green-tide mitigation technique in the lower part of the Sook Stream (Chusori) of Daecheong Reservoir from June 27 to August 24, 2014. And the effects were compared with weekly monitoring result of the watching station of the algae alert system (AAS) as well as test beds reach. The green-tide in a test bed was begun from the upstream, and it was gradually transferred and spread toward the downstream by the hydrological factors. The total amount of algae removed by algae removal device during the test period was 33,920 kg, and solids dewatered by natural gravity was 8,480 kg. Also chlorophyll-a content was 2.83 kg, the number of blue-green algae cells was equivalent to 78.6×1014 cells. Compared with the results of the watching station of AAS, the pre-concentrate removal work in the outbreak waters was able to suggest the possibility of green-tide mitigation. In addition, an effective management of the green-tide was required spatial and temporal occurrence information and practical device technology. Particularly, the optimal timing of algae removal in the river-reservoir hybrid system was recommended at times before the monsoon rainy season and reached the lowest water level.

목 적 : GRAPPA 기법을 이용하는 검사에서 GRAPPA factor는 k-공간 내에 누락시 킬 신호의 양을 결정하고 검사시간을 줄이는 변수이다. 하지만 GRAPPA factor가 증가할수록 영상의 SNR이 저하되고 인공물이 증가하는 제한점이 있다. 따라서 본 연구에서는 GRAPPA factor와 ACS Line 수를 변화시켜 영상 화질과의 상관관계를 평가하여 분석하고자 하였다. 대상 및 방법 : VIBE sequence를 사용하여 GRAPPA factor를 2, 3, 4, 5로 ACS Line의 수는 20, 40, 60, 80, 100, 120로 증가시키고 검사하였다. 화질 평가를 위해 영상의 SNR을 측정하였고 GRAPPA 기법을 이용하지 않은 영상과 GRAPPA 기법을 이용한 영상의 유사성(SSIM)을 평가하였다. 또한 GRAPPA factor를 2, 3, 4, 5로 고정하였을 때 ACS Line과 SNR, ACS Line과 SSIM의 상관관계분석을 실시하였다. 결 과 : GRAPPA factor가 증가 할수록 SNR은 저하되었고 같은 GRAPPA factor의 조건에서 ACS line의 수가 증가 할수록 SNR은 증가되었다. GRAPPA 기법을 이용하지 않은 영상과 GARPPA기법을 이용한 영상의 유사성 평가에서는 GRAPPA factor가 증가 될수록 SSIM은 저하되었고 같은 GRAPPA factor의 조건에서 ACS Line의 수가 증가 될수록 SSIM은 1에 가까워졌다. ACS Line의 수와 SNR의 상관관계분석 결과 GRAPPA factor가 2일 경우 Pearson 상관계수가 0.291, GRAPPA factor가 3일 경우 0.458, GRAPPA factor가 4일 경우 0.779, GRAPPA factor가 5일 경우 0.88로 나타났다. ACS Line의 수와 SSIM의 상관관계분석 결과 GRAPPA factor가 2일 경우 Pearson 상관계수가 0.787, GRAPPA factor가 3일 경우 0.792, GRAPPA factor가 4일 경우 0.918, GRAPPA factor가 5일 경우 0.946로 나타났다. 결 론 : GRAPPA 기법을 이용하는 검사에서 GRAPPA factor를 증가시킬 경우 검사시간이 감소하지만 SNR이 저하되고 인공물이 증가하는 제한점이 있다. 따라서 GRAPPA 기법을 이용하였을 때 검사에 영향을 주지 않은 시간 내에서 ACS Line의 수를 최대로 사용하면 SNR 증강 효과와 더불어 인공물을 개선할 수 있고 GRAPPA factor가 높을 경우 ACS Line의 수를 증가시키면 개선효과가 더 클 것으로 사료된다.

목 적 : 최근 관상동맥 경화반(coronary plaque)을 진단하기 위해 X-ray를 이용한 관상동맥 조영술(coronary angiography), fractional flow wire를 통한 관상동맥 혈류측정 (fractional flow reserve, FFR),혈관내초음파(intravascular ultrasound. IVUS), 심혈관 광간섭 단층촬영(optical coherence tomography, OCT) 등 여러 가지 기법들이 사용되고 있다. 이 중 관상동맥 경화반(coronary plaque) 을 평가할 수 있는 PC-VENC를 이용한 MR- FFR(fractional flow reserve)이 개발되어 기존의 비침습적 영상기법인 관상동맥 CT와 OCT, FFR등 침습적 영상기법과 비교하여 연구가 진행되고 있다. 이에 본 연구는 관상동맥 경화반(coronary plaque)을 평가하는 MR-FFR 검사에서 사용되는 2D PC-VENC 기법의 최적화 요인에 대하여 알아보고자 한다. 대상 및 방법 : 2015년 8월부터 2016년 1월까지 관상동맥의 근위부에 의미 있는 동맥경화반이 관찰되어 침습적 관상동맥 조영술과 OCT 또는 FFR측정이 예정된 환자 30명을 대상으로 MR-FFR 검사를 진행하였다. 3.0T MR(Trio, Siemens Healthcare, Erlangen, Germany) 장비를 사용하였다. 코일은 phased-array body coil을 사용하였고 parameter는 fat saturation을 사용하고 in-plane resolution은 0.5-0.6 × 0.5-0.6 mm², slice thickness 는 3.2 mm, VENC 범위는 동맥 경화반 상태에 따라 40-80 cm/s(3방향 z, x, y), cardiac phases는 2 (segments/phase), scan time은 slice당 4-8min/slice으로 설정하였다. 결 과 : Stenosis 정도 40%이하는 4명(13%), 40~70% 에서는 25명(77%), 70%이상은 3명(10%)으로 검사하였다. 40%이하에서의 VENC측정값은 normal 구간에서 40cm/sec, plaque 구간에서는 41±2.5cm/sec로 나타났고, 40~70%에서의 VENC측정값은 normal에서 40cm/sec, plaque구간에서는 46±4.6cm/sec로 70%이상에서의 VENC 측정값은 normal, plaque구간 모두 45cm/sec로 나타났다. VENC측정값 별 평균 검사시간은 35~40cm/sec에서 91.2분, VENC 40~45cm/sec에서 98.4분, VENC 45~50cm/sec에서 98.4분, VENC 50cm/sec 이상에서 107분이 소요되었다. 결 론 : 관상동맥 경화반 진단을 위한 2D PC-VENC 기법 사용 시, 본 연구에서 측정된 stenosis 정도에 따라 적정 VENC측정값을 사용하여 장시간의 검사시간 낭비를 최소화 할 수 있다. 또한 미리 알고 있는 stenosis정보를 통해 guide가 될 수 있는 VENC값을 사용함으로써 검사시간의 효율화를 구현할 수 있다.

In this study, we studied the damage area detection of the composite tension specimens under fatigue loading by using image processing techniques. The aim of this study is to detect the area of the damage region on the basis of original image. Basically we have used Matlab program. This study analyzed a total of six specimens under cyclic loading and the results using a user algorithm and analysis procedures of step 7. The damaged area was well detected except 3,000 cyclic loading. Accuracy of damage area detection is determined to be excellent by 83.3%(5/6). In general, however, in order to automatically detect the damaged area must develop an algorithm for setting the number of multi-threshold automatically. This is to perform the studies in the future.

In this paper, a 2-DOF electromechanical impedance model of PZT material-aluminum interface member is proposed. The primary motivation is to control the effective frequency range in impedance-based local health monitoring practices. The proposed method focuses on the predetermination of the effective frequency band and the wireless impedance sensing possibility for damage detection in structural connections like tendon anchorage, etc. Firstly, a 2-DOF impedance model is proposed for modelling the PZT interface-host structure system. Secondly, the prototype design of the PZT interface is developed based on the analysis of the 2-DOF impedance model and the local dynamic characteristics of the composite aluminum interface-host structure system. Finally, the feasibility of the proposed 2-DOF impedance model is numerically verified by predetermining the effective frequency band for the impedance monitoring in a cable-anchorage connection.

The color that painted on the ground of Dancheong becomes Gachil(basecoat)-Dancheong and underpainting of Moro-Dancheong or Geum-Dancheong. So, the color of underpainting is the most important element that determines impression of the building. Thus, the architecture after using “Sangrokhadan” has different characters from what it had been. In the existing perception toward the background color of Dancheong, it was considered the characters of Korean Dancheong so-called “Sangrokhadan” that paint vertical elements like columns red and upper part of the columns green. But this study examined the color of Dancheong according to the era and region before and after Goryeo Dynasty era, then it reveals that Sangrokhadan technique was applied from the 14th century in the late Goryeo Dynasty. One of the Goryeo architecture, Geungnakjeon Hall of Bongjeongsa Temple is thought to be a previous style that is not applied “Sangrokhadan” technique because old elements are painted red pigment.

Potato Virus Y (PVY) (Potyviridae: potyvirus) is one of the serious emerging virus of seed potato world-wide. It affects the seed potato by transmitting non-persistently via aphids. Here, we developed a simple PVY detection method which used the boiling technique for releasing of the viral RNA from aphid such as stylet and amplification by PVY specific primers located in the viral coat protein gene which suitable for various strains. This simplified method could save the time compared to earlier detection method due to the simplified RNA extraction step. Following this procedure, we tested this one step RT-PCR based PVY detection method by using three PVY vectoring aphid species (M. persicae, A. gossypii and M. euphorbiae) as well as other sucking type insect such as thrips (F. occidentalis). This PVY detection method is rapid, easy-to-use and suitable for large-scale testing in laboratories of seed potato.

Monochamus saltuarius is one of the insect vector of pine wilt disease with Monochamus alternatus. The present study aimed to investigate the dose to induce sterile and the effect of sterility according to the gender of M. saltuarius. As the electron beam irradiation dose increased, the hatchability, adult eclosion rate and longevity of the former mid and late maturation feeding stage of adults was slightly reduced. However, there was no difference between these two adults. In addition, female adults were more sensitive to the electron beam than the male adults. Hatchability of the F1 generation of ♂T × ♀N o r♀T × ♂N (T: 200 Gy electron beam irradiation, N: 0 Gy) was completely suppressed. As electron beam irradiation dose increased, the fecundity of female adults were slightly decreased. Results by comet assay showed that electron beam irradiation induced as dose increased DNA damage in M. saltuarius adults. These results suggest that SIT using electron beam may be useful for control of M. saltuarius.

In korea, only small amount of nonstructural lightweight concrete is being used through indirect effects such as heat insulation property and soundproofing rather than structural elements due to lack of structural lightweight aggregates and lack of understanding about lightweight concrete development, etc. That`s why structural lightweight concrete to reduce weight has not been put to practical use. This study is a part of high strength lightweight aggregate concrete researches using lightweight aggregates and the purpose of this study is to find out the basic physical characteristics and tension cracking fracture characteristics of lightweight concrete. Crack Mouth Opening Displacement is measured through 3 point flexure experiment about notch beam. Load-CMOD characteristics are examined through rules of countries, characteristics of lightweight concrete and tension cracking fracture experiments. The degree of tensile characteristic alteration according to size changes of specimen and the characteristics about crack surface are analyzed. The changes of softening curve are analyzed and fracture energy is drawn through inverse analysis by the obtained Load-CMOD curve. To decide fracture energy and analysis parametric, inverse analysis is conducted and Ant Colony Method is conducted for optimization and then a way to find out optimal parameterization fracture energy is suggested.

This study considers the modern expression of oriental esthetics by analyzing the fashion design with the Chinese ink technique based on the concept of Chi-Yun- Sheng-Tung, which was regarded as the best rule of art creation in oriental history. This study was performed by conducting a literature review of related books and advanced studies, and then, collection analysis was done with photos derived from fashion websites (seoulfashionweek.org, chinafashionweek.org, vogue.com, firstview. com) from 2010 S/S to 2016 S/S. A total of 317 fashion photos of designs created using the Chinese ink technique by Korean designers at Seoul Fashion Week and Chinese designers at China Fashion Week were analyzed. The contemporary fashions created with the Chinese ink technique were characterized by, first, the bold brush strokes and natural spreading effects of Chinese ink, second, the emphasis of empty space by taking essential elements, and third, the coexistence of deep Chinese ink colors with modern primary colors. The formativeness of the contemporary fashions created with Chinese ink technique based on Chi-Yun-Sheng-Tung were as follows: first, temperance, pursuing spiritual and minimal expression, second, empty space, making design elements interact and pursue harmony, third, changeable rhythm, symbolizing the growth and variation revealing the power of life, and fourth, vitality, represented in the rhythmical movement of the brush. This study was based on the oriental esthetics inherent in Chi-Yun-Sheng-Tung, and it attempted to analyze contemporary fashion design. The aim was to show the possibility of modern applications to traditional values, and it can be a meaningful case in design planning based on culture.

PURPOSES: This study aims to show the difference of the binder aging level in the hot-mix asphalt (HMA) mixture after short-term aging (SA) under different aging conditions, such as mixture temperature and duration in hour. METHODS: Three SA times (i.e., 1 h, 2 h, and 4 h) at two temperatures (i.e., 160℃ and 180℃) were used for the normal mixtures prepared using a PG64-22 asphalt. The field long-term aging (LA) was simulated by applying the same LA procedure (65 h at 110℃) to all compacted specimens, prepared at the air void of 7% using each SA-treated mixture, in a convection oven. The binder aging level was measured in terms of large molecular size by gel-permeation chromatography (GPC) from the mixture and the absolute viscosity (AV) from the recovered binder. The aging levels were evaluated using those two properties after SA and LA, and then compared based on the normal SA (NSA) mixture (1 h at 160℃). The service life reduction caused by SA in various conditions was estimated based on the aging level of the field cores from different locations in various service lives. RESULTS: The results of the laboratory evaluation indicated that the binder of the mixture, which was treated at longer SA time and higher temperature, showed a significantly higher aging level than the NSA mixture. The binder aging level from a longer time, such as 2 h and 4 h SA, or at a higher temperature (180℃), were estimated to be similar to that of the mixtures, which had already been in field service for several years. CONCLUSIONS : The HMA mixture should be produced at a moderate temperature, such as 160℃, and placed within a limited hauling and queuing time to avoid a significant short-term aging of the binder before placement in the field pavement. The SA for a longer time at a higher temperature than the NSA condition was found to be detrimental to the service life of the asphalt pavement.

Infrared thermography provides the colorful images of concerning area where local changes of surface temperature occurs and can be used to measure the fine temperature of human body. Unlike the radiography technique, it is determined by the presence or absence of existing anatomical principles capable of quantitative evaluation and visible to the physiological and functional state of the human body. In this paper, it was studied the characteristics of dynamic motion conditions in the hands due to physiological changes of temperature distribution. The results showed that the difference between the change in temperature characteristics for the left and right hand.

고분자전해질 연료전지용 막-전극접합체 내 전극에는 삼상계면을 구성하기 위하여 이온 전도가 가능한 이오노머가 함유되어야한다. 따라서 촉매슬러리 제조를 위해 이오노머가 용매 시스템에 분산되어 있는 분산 용액 형태이어야 한다. 하지만 상용 이오노머 분산 용액의 종류가 제한되어 있으며 개발 물질로 제 조된 전해질막과의 호환성을 위해 동일 물질 기반의 분산 용액으로의 전환이 요구된다. 본 연구에서는 동결 건조 방식을 활용한 고분자 분쇄방법을 도입하여 이오노머를 분쇄하고 이를 활용한 이오노머 분쇄 용액을 제조하여 다양한 물성 및 성능을 조사하였다.

Monochamus alternatus is one of the insect vector of pine wilt disease with Monochamus saltuarius. The present study aimed to investigate the dose to induce sterile and the effect of sterility according to the gender of M. alternatus. As the electron beam irradiation dose increased, the longevity of the mid and late maturation feeding stage of adults was slightly reduced. However, there was no difference between these two adults. In addition, female adults were more sensitive to the electron beam than the male adults. Hatchability of the F1 generation of ♂T×♀N or ♀T×♂N (T: 200 Gy electron beam irradiation, N: 0 Gy) was completely suppressed. As electron beam irradiation dose increased, the fecundity of female adults were slightly decreased. Results by comet assay showed that electron beam irradiation induced as dose increased DNA damage in M. alternatus adults. These results suggest that SIT using electron beam may be useful for control of M. alternatus.

The first record of Melon thrips, Thrips palmi Karny, was in 1993 in Korea, and the species has become severe pest in agricultural industry. We used two different SDMs(Species Distribution Model) which have different approaches to analyse potential distribution of the pest species in climate change scenario, MaxEnt and CLIMEX. The MaxEnt model uses historical occurrence records with environmental variables to estimate the realized niche, and CLIMEX model simulates the fundamental niche of the object based on the seasonal phenology. In MaxEnt simulation, we reduced the number of variables to avoid multi-collinearity problem until we had no pairs with an absolute Pearson correlation coefficient higher than 0.8. BIO1(Annual Mean Temperature), BIO2(Mean diurnal range), BIO3(Isothermality), BIO4(Temperature seasonality) were finally selected as predictor, and we used 10 fold cross validation option to replicate. The averaged results were used to index analysis. The CLIMEX results, The Ecoclimate Index(EI), were also normalized in 0 to 1 scale to analysis. Under RCP 8.5 climate change scenario, in 2070s, the distribution of Thrips palmi was predicted to expand their territory overall agricultural area in Korea.

본 연구는 비고전 감쇠를 가지는 구조물, 모드가 매우 인접되어 있는 구조물의 모드를 분리하기 위하여 제안된 최적화 상태 공간 모드분리법의 검증을 목적으로 하고 있다. 실구조물에 대한 모드분리의 가능성 및 적용성을 위하여 40층 규모의 건물에 동조질 량감쇠기가 설치된 시스템을 대상으로 하였으며 그로부터 계측된 응답에 모드분리법을 적용하였다. 모드분리 결과를 보면, 해당 모드 에서의 에너지 집중을 목적함수로 설정한 경우에는 이웃한 인접모드의 고유진동수 부근에서 파워스펙트럼 값을 인위적으로 작게하여 왜곡하는 경향이 나타나는 것을 확인할 수 있었다. 이러한 왜곡현상을 방지하기 위해 도입된 구속조건과 이를 이용한 목적함수의 설 정을 통해서 인접한 모드가 효과적으로 분리 가능함을 확인 할 수 있었다.

목적 및 배경 : 본 연구의 목적은 Lumbar Spine Routine 자기공명영상에서 ProSet(Principles of the selective excitation technique)기법이 유용한 검사임에도 임상에서 많이 사용되지 않으며 2D영상만 주로 사용하고 3D영상으로 잘 분석되지 않고 있다. 이에 ProSet기법의 3D영상의 중요성과 요추 자기공명영상에서의 ProSet기법의 유용성을 알리고자 한다. 대상 및 방법 : 본원을 내원하여 2011~2014년 요추 자기공명영상 검사를 시행한 환자를 대상으로 ProSet 2D영상과 3D영상을 분석하였다. 연구에 이용한 실험 장비는 Philips사의 Gyroscan Intera 1.5Tesla로 Spine Array coil을 사용하였다. 결 과 : 요추 자기공명영상 검사의 ProSet 2D영상과 3D영상을 영상의학과 전문의 3명에게 보여주었다. 2D영상보다는 3D영상에서의 신경근 압박(Nerve root compression)정도와 신경근의 부종 등이 잘 묘사되어 3D영상의 진단적 가치가 더 높았다. 결 론 : 요추(Lumbar spine) 자기공명영상에서 ProSet의 2D영상보다 3D영상의 신경근 압박 및 부종 등의 진단적 가치가 높았다