9% nickel steel has remarkable mechanical properties in a cryogenic condition and is widely used in storage containers for LNG fueled ships. Demand for laser welding rather than conventional arc welding has grown to increase manufacturing efficiency. However there are various types of heat sources which are suggested by other researchers. With that, it is difficult to select a proper heat source shape for welding conditions. The author proposed a representative heat source model that can cover most of suggested heat source models through previous studies. Welding power was fixed at 4kW and the speed was changed to 1.0m/min, 1.5m/min, and 2.0m/min respectively. The shapes of the welding heat sources were derived, and the tendency of the main parameters was also deducted. It was observed that the width and depth of the weld bead decreased as the welding speed increased through welding experiment, parameters of welding heat source are changed linearly. Based on this study, it is expected that it will be possible to estimate the shape of the heat source under untested welding conditions.

Wireless sensors are more favorable in measuring structural response compared to conventional sensors in terms of them being easier to use with no issues with cables and them being considerably cheaper. Previous tests have been conducted to analyze the performance of MEMS (Micro Electro Mechanical Systems) sensor in sinusoidal excitation tests. This paper analyzes the performance of in-built MEMS sensors in devices by comparing with an ICP sensor as the reference. Earthquake input amplitude excitation in shaking table tests was done. Results show that MEMS sensors are more accurate in measuring higher input amplitude measurements which range from 100gal to 250gal than at lower input amplitudes which range from 10gal to 50gal. This confirms the results obtained in previous sinusoidal tests. It was also seen that natural frequency results have lower error values which range from 0% to 3.92% in comparison to the response spectra results. This also confirms that in-built MEMS sensors in mobile devices are good at estimating natural frequency of structures. In addition, it was also seen that earthquake input amplitudes with more frequency contents (Gyeongju) had considerably higher error values than Pohang excitation tests which has less frequency contents.

Wireless sensors are more favorable in measuring structural response compared to conventional sensors. This is because they are easier to use with no issues with cables and are considerably cheaper. There are several applications that can be used in recording and analyzing data from MEMS sensor installed on an iPhone. The Vibration App is one of the applications used and there has not been adequate research conducted in analyzing the performance of this App. This paper analyzed the performance of the Vibration App by comparing it with the performance of an ICP sensor. Results show that natural frequency results are more accurate (error less than 5%) in comparison to the amplitude results. This means that built- in MEMS sensor in smartphones are good at estimating natural frequency of structures. In addition, it was seen that the results became more accurate at higher frequencies (5.0Hz and 10.0Hz).

For the 3D game visual effects, the deferred rendering can only consider only the scene image resolution regardless of the scene complexity. Therefore, it is effective in processing realistic visual effects using many geometric buffers as multiple render targets. This paper uses the deferred rendering for the 3D game visual effects such as dynamic lights, specular, shadow, motion blur, and water shading. The 3D game supporting deferred rendering is developed to evaluate various 3D rendering effects with variation of the screen resolution in terms of the rendering speed and PSNR image quality. The performance results show that the rendering speed of the 3D visual effect techniques with 1280x960 resolution is average 56.0% better than that with 640x480 resolution. Also, the average PSNR is getting better as the screen resolution gets higher. The PSNR of the 3D visual effect techniques with 1152x864 resolution is average 30.9% better than that with 640x480 resolution.

PURPOSES : The purpose of this study is to identify the factors affecting the effectiveness of speed limit change that is defined as the amount of increased travel speed. METHODS: A ordered logit model was adopted to analyze the relationship between the change in travel speed and contributing factors. A stretch of Kyungbu freeway was selected for the analysis because the Korea expressway corporation has raised speed limit from 100km/h to 110km/h since September 1st in 2010. RESULTS: The results showed that geometric design elements, speeding cameras, and section length were identified as factors contributing the effectiveness. Contributing geometric design elements include the number of horizontal curves and vertical curves that do not meet the design requirement with 110km/h speed limit. CONCLUSIONS: The outcome of this study will be used for establishing various traffic operations and control strategies for freeway speed management.

터널, 교량, 커브구간 등 교통사고위험이 연속적으로 존재하는 도로구간에서의 대형교통사고를 예방하기 위하여 경찰청은 2007년 1월 위험도로구간에서 교통관리 대책의 일환으로서 무인구간속도위반단속시스템 시범설치 운영을 결정하였다. 2007년 12월 영동고속도로 둔내터널 강릉방면을 시작으로 2011년 7월 현재까지 고속도로 8개 구간 및 국도 3개 구간, 총 11개 구간 85km에서 무인구간속도위반단속시스템이 운영 중에 있다. 하지만 이러한 무인구간단속시스템의 설치가 교통사고 감소에 얼마나 기여하는지에 대한 실질적인 연구가 부족하였다. 따라서 본 연구에서는 고속도로를 중심으로 무인구간속도위반단속시 스템 설치 전 후 교통사고건수를 체계적으로 비교할 수 있는 비교그룹방법을 이용하여 무인구간속도위반단속시스템의 설치효과를 분석하고자 한다. 이를 위하여 2008년 고속도로에 설치된 무인구간속도위반단속시스템을 대상으로 설치 전 후 각 1년의 사고이력자료를 수집하여 분석하였다. 그 결과, 무인구간속도위반단속시스템을 설치하지 않았을 경우에 비해 사업을 시행함으로서 49.97% 사고감소효과가 있는 것으로 나타났다.

The main purposes of this study were to find the correlation between walking ability assessment tools using the Modified Barthel Index (MBI), Functional Independence Measure (FIM), Spinal Cord Injury Measurement II (SCIM II), Walking Index for Spinal Cord Injury (WISCI), walking velocity, and walking endurance. The study population consisted of 56 patients with spinal cord injury referred to the department of Rehabilitative Medicine in the National Rehabilitation Hospital. All subjects were ambulatory with or without an assistive device. All participants were assessed by MBI, FIM, SCIM II, WISCI, walking velocity, and walking endurance. The data were analyzed using Pearson correlation analysis and X2. There was significant correlation between the MBI, FIM, SCIM II, WISCI, walking velocity, and walking endurance (p<.01). In particular, WISCI has a significant correlation with SCIM II(p<.001). Therefore the WISCI scale is an appropriate assessment tool to predict the gait ability of patients with spinal cord injury. Further study about MBI, FIM, SCIM II, WISCI, walking velocity, and walking endurance is needed using a longitudinal study design.

목적 : Dynavision을 이용한 성인 남녀의 시각운동 반응 속도를 측정하여 정상인의 표준치를 밝히고, 임상에서 이 도구를 이용한 훈련을 시행할 때 대상자의 성별을 고려하여 적용함을 목표로 실험을 실시하였다. 연구방법 : 대상자는 대학생 62명을 대상으로(남: 31, 여: 31), 나이는 19～27세로, 평균나이는 21.48±2.19세이었다. 국소적인 시각적 주의력과 주변 시각적 주의력 그리고 시지각 전체 영역에서 시각 탐색, 시각반응의 측정 및 훈련하도록 고안된 dynavision의 여러 훈련 프로그램 중 본 연구에서는 self-paced 60초와 240초 프로그램을 사용하였다. 결과 : 남녀 두 그룹간 시각운동 반응 속도에서 유의한 차이를 보였는데, self-paced 60초와 240초 훈련 프로그램 모두에서 남자들이 여자들보다 반응 속도가 빠르게 나타났다(p<0.05). 결론 : Dynavision을 시지각 손상 환자를 평가하고 훈련시킬 때 성별에 따른 정상 수행 속도를 고려하여 적용하여야 할 것이다.

This study deals with human reaction speed according to human physical conditions (body size) such as head width, thickness, breast width, arm extent, and age Especially, the results of this study are compared between young and old generation. According t

지반의 횡파 속도 단면은 주로 다운흘 탄성파 탐사에 의존해 왔으나 최근에 MASW와 같은 표면파 탐사방법과 SCPT와 같은 탄성파 콘 관입시험법 등이 개발되어 사용되고 있다. 본 연구에서는 비고결 퇴적물에서 다운홀 탄성파 탐사, MASW, SCPT 등을 사용하여 횡파 속도 단면을 구하고 이들을 시추조사 결과와 비교하였다. 그 결과 퇴적물상의변화와 횡파 속도 변화는 밀접한 관계가 있음을 알 수 있었으며, 세 가지 횡파 속도 단면 중 SCPT가 퇴적물상의 변화에 가장 민감하게 반응하는 것을 알 수 있었다. SCPT 결과 퇴적층 내 약 8∼l2m 깊이에 주로 점토질 모래로 구성되어 있는 저속도 층이 있음을 알 수 있었다.

표면파 탐사는 탄성파를 이용한 여러 가지 다른 탐사 방법과 비교하여 독특한 장점들을 가지고 있다. 그러나 이 방법은 최근에 개발되기 시작하여 아직 연구 결과가 많이 축적되지 않은 분야이다. 이 연구에서는 지반 공학적 성질이 서로 다를 것으로 예상되는 여러 지역에서 표면파 탐사자료를 획득하여 그 분산곡선의 특징을 찾아보았다. 또한 분산곡선을 역산하여 S파 속도구조를 구하여 이를 시추조사 결과와 비교하였다. 그 결과 퇴적물상이나 암석상의 변화가 S파속도의 급격한 변화와 관련되어 있음을 확인하였다. 이것은 표면파 탐사법을 이용하여 퇴적물이나 암석의 물리적 성질이 급격하게 변화하는 경계면을 구별할 수 있는 가능성을 시사한다.

Manual dexterity is often evaluated in rehabilitation because of its contribution to upper limb performance and to individual functional independence. Dexterity depends on age, sex, anthropometric measurements of the hand and sensitivity. The purpose of this study was to compare the finger dexterity with and without wearing different types of gloves (latex gloves and cotton gloves), and to investigate the correlation among the different measurement tools (VALPAR component work samples, O‘conner finger dexterity, and Minnesota grooved pegboard) for finger dexterity. Fifteen healthy young subjects (male: 6, female: 9) had a mean age of 26 years were evaluated. The results were as follows: There was no significant difference in finger dexterity between male and female group at all conditions except for wearing cotton glove condition. The finger dexterity was significant difference in Minnesota grooved pegboard test among conditions(bare hand, latex gloves and cotton gloves). However, finger dexterities were no significant differenece in other tests at different conditions. There was high correlation between measurement tool except for the Size discrimination item in VALPAR test. The results of this study suggest that Minnesota grooved pegboard test maybe a sensitive tool to measure the finger dexterity at sensory constrained conditions.

This study was designed to compare re-epithelization rate/feature of conjunctival epithelial cell on amniotic membrane and anatomical difference between normal amniotic membrane and de-epithelial amniotic membrane. Human conjunctival tissue obtained while cataract operation were used in this study. Primary cultured human conjunctival epithelial cell and fibroblast were incubated on intact amniotic membrane and de-epithelialized amniotic membrane. After incubation for 3, 5 and 7 days, re-epithelization rate was analyzed using cell tracker and microscopic feature was examined using methylene blue and hematoxylin- eosin stain. For cell marker analysis, cytokeratin 14 and vimentin antibody immunofluorescence stain were used. Clearance rate of epithelial cells on amniotic membrane using trypsin was better than using 25% alcohol. The results of reepithelization rate using cell tracker, HaCaT, conjunctival firbroblast, and epithelial cell were rapidly incubated on deepithelialized amniotic membrane. Wound healing and re-epithelization were more rapidly induced on de-epithelialized amniotic membrane on permanent amniotic membrane graft.

Background : This study was carried out to investigate the possibility of cosmetics materials by comparing growth characteristics, photosynthetic rate and major functional components of Rosa multiflora and Perilla frutescens at different altitudes. Methods and Results : This experiment is being carried out in April 2018 in Namwon (500 m above sea level) and Iksan (15 m above sea level) in Jeollabuk-do. The growth characteristics of R. multiflora were investigated at the end of May. Flowers were collected at this time and used as samples for functional analysis. The growth characteristics of P. frutescens were investigated in the middle of August and the ground part was collected at this time and used as a sample for functional analysis. Photosynthetic rates were measured using LCpro+ (ADC, UK). The marker compound were investigated and analyzed using HPLC Alliance e2695 and 2998 PDA detector (Waters, USA). Photosynthetic rate (based on 1,600 μ mole of light intensity) was measured in mid-June as follows. The R. multiflora showed 9.8 μ mole․CO2/㎡/s in Iksan and 7.9 μmole․CO2/㎡/s in Namwon. The P. frutescens showed 15.0 μmole․CO2/㎡/s in Iksan and 8.8 μmole․CO2/㎡/s in Namwon. Overall, Photosynthetic rate was higher in Iksan. As a result of analyzing 18 kinds of marker compound, gallic acid and astragalin were found in R. multiflora, caffeic acid and rosmarinic acid were found in P. frutescens. Gallic acid and Astragalin of R. multiflora showed 5.4 ㎎/g and 28.4 ㎎/g in Iksan and 3.2 ㎎/g and 21.6 ㎎/g in Namwon, respectively. Caffeic acid and rosmarinic acid of P. frutescens were 2.7 ㎎/g and 49.7 ㎎/g in Iksan and 2.5 ㎎/g and 33.6 ㎎/g in Namwon, respectively. Conclusion : Comparing the yield of the harvesting parts by region, both R. multiflora and P. frutescens was higher in Namwon. As a result of quantitative analysis of four detected elements of gallic acid, astragalin, caffeic acid and rosmarinic acid, all four components were high in Iksan. It is considered that this is due to optical environment difference.

우리나라의 하수슬러지 처리방법은 해양투기가 약 70%를 차지해왔으나, 런던협약으로 인해 해양투기 규제가 강화됨에 따라 소각 및 연료화 사례가 증가되고 있다. 그러나, 하수슬러지는 함수율이 높고 유기물함량이 상대적으로 낮기 때문에, 소각이나 연료화를 위해서는 건조전처리를 통해 함수율을 낮추는 과정이 반드시 필요하다. 슬러지 건조기는 열원의 접촉형태에 따라 직접건조방식과 간접건조방식으로 구분되며, 국내의 경우에는 소각로에서 발생한 폐열(폐스팀)을 이용하는 간접건조방식이 주로 적용된다. 슬러지는 유입원수, 소화･열처리 유무, 탈수보조제의 종류 등에 따라 건조속도가 차이가 발생하기 때문에, 건조기 용량 결정시에 대상슬러지의 건조특성을 사전에 실험을 통해 파악하는 것이 필요하다. 특히, 건조 과정중 함수율 50~70% 영역에서 점성이 높아지고, 슬러지가 건조기에 부착되어 건조효율을 저하시키기 때문에 주의가 요구된다. 본 연구는 동일한 타입의 건조기가 설치된 두 개의 하수처리장을 대상으로 진행되었다. 하수처리장에서는 각각 혐기소화슬러지와 호기성슬러지를 건조처리 중이었으며, 혐기성소화슬러지가 안정적으로 건조가 이루어지고 있는 반면 호기성슬러지는 설계용량의 50% 수준으로 운영되고 있었다. 운영중인 건조기에서 위치별로 슬러지 함수율을 측정하였으며, 혐기소화슬러지는 함수율 60~70% 수준에서 점성구간(Glue zone)을 형성된 반면, 호기성슬러지는 함수율 30% 까지 점성구간이 유지되는 것으로 확인되었다. 호기성슬러지는 넓은 함수율 범위에서 고점성을 유지하였으며, 건조기에 부착되어 건조효율이 저하된 것으로 판단된다. 실험실의 건조오븐을 이용하여 동일한 조건에서 건조속도를 비교한 결과, 혐기소화슬러지는 (초기함수율 82%) 목표 함수율 10% 이하로 건조하기 위해서 250분의 건조시간이 필요하였으나 호기성슬러지는 500분 이상의 건조시간이 필요한 것으로 나타났다. 또한 혐기소화슬러지는 건조과정에서 자연적으로 분말화가 진행되는 반면, 호기성슬러지는 입자끼리 뭉쳐져 있는 현상이 관찰되었다. 우리나라의 건조기 설계는 아직까지 제작사의 경험이나 기존의 설계사례에 의존하고 있는 실정이다. 그러나, 본 실험결과에서 나타난 바와 같이 슬러지는 성상에 따라 건조속도가 차이가 발생하므로, 건조기 설계에 앞서 슬러지 건조속도 등을 측정하여 반영할 필요가 있다. 특히, 호기성슬러지를 건조 처리하는 경우에는, 혐기소화슬러지에 비해 건조속도가 크게 차이가 날 수 있으므로 설계시 유의가 필요하다.

The surface properties and adsorption rates of activated carbon modified with acid and base were compared. The distribution ratio of C and C-H on the surface of activated carbon were decreased by modification with acid and base, but the distribution ratio of C-O, C=O, and O=C-O were increased. Base modification damaged the surface of activated carbon more than acid modification, it caused the effect of 6 percent increments of surface area. Adsorption rate model was more suitable to second order equation than first order equation. Adsorption rate was controlled by adsorption in pore better than in surface.