목 적：평균 수명 연장으로 고령화에 따른 노인층 증가에 따라 노인 의료건수가 더욱 증가하고 있다. 노인층 MRCP 검사 또한 증가하는 추세이며, 호흡이 중요한 MRCP 검사 시 노인 환자들의 호흡은 의학적 정보 를 얻는 중요한 요소가 된다. 보통 MRCP 검사 시 일반 환자들에서는 호기(expiration) 후 호흡 정지 영상을 얻어 검사를 시행하고 있다. 호흡이 불안정한 노인 환자들 중 호기와 흡기(inhalation) 후 호흡 정지 검사 시 영상의 진단적 가치의 차이점이 있는지 알아보고자 한다. 대상 및 방법：2017년 10월부터 2017년 12월까지 MRCP 검사 시 호흡이 불안정한 환자를 선별해 환자(남성 11명 평균연령-68.4세, 여성 7명 평균연령-68.9세)을 대상으로 하였다. 실험 장비는 Siemence verio 3.0T 와 6 channel 복부 Coil을 사용하였다. 검사 전 환자들에게 호흡에 대한 충분한 설명 후 검사를 시행하였으며 sequence는 T2 Haste axial, coronal를 시행하였고, 각 시퀀스 검사 시 매개변수는 동일하게 하였다. 실험A(호기,expiration후)와 실 험B(흡기,inhalation후) 호흡 정지 영상을 얻은 후 복부 임사 판독의 2명, 방사선사 3명이 정성적 평가를 하였다. 그리고 실험A로 호흡 정지검사가 힘든 환자는 실험B로 검사를 시행하였다. 정성적 평가로 영상 의 선예도, 연속성, 전체 영상의 질에 대하여 각 5단계(1=매우 나쁨,2=나쁨,3=보통,4=좋음,5=매우 좋 음)로 평가하였다. 결 과：영상의 선예도, 연속성, 영상의 질에 대한 평가자 5명의 정성적 평가는 실험A에서 T2 axial에서는 각각 평균 3.8, 4.12, 3.96 ,4.14 ,4. T2 coronal에서는 각각 평균 3.84, 3.96, 4.12, 4.16, 4.12였고, 실험 B에서 T2 axial에서는 각각 평균 4.22, 4.24, 4.2, 4.26, 4.4 T2 coronal에서는 각각 평균 4.26, 4.22, 4.24, 4.28, 4.36의 결과를 보였다. 대상자 18명중 8명은 호기 후 호흡 정지가 어려워 검사가 안됐으며, 그 중 4명은 흡기 후 검사에서는 호흡 정지가 가능해 검사를 마칠 수 있었다. 결 론：MRCP 복부 검사 시 호기 후 보다 흡기 후 검사에서 영상의 질의 평가에서 더 우수하게 나타났고, 호기 후 호흡 정지가 안 되는 환자는 흡기 후 호흡 정지가 좀 더 수월하게 나타났다. 일반적으로 MRCP 검사는 호기 후 검사의 완성도가 높으나 호기 후 14-15초의 호흡 정지가 어려운 노인 환자들에 대해서는 흡기 후 검사를 시행하는 경우도 영상의 진단적 가치가 있어 호기 후 호흡 불안정에 따른 영상의 불완성도 또는 검사의 실패를 대처 할 수 있다고 사료된다.

Stainless steel is being used in various industries such as automobile and aerospace for its cheap manufacturing cost and excellent mechanical properties. However, stainless steel failed to stably protect a specimen with a Cr2O3 protective layer at temperatures above 1000 ℃. Thus, improving the high temperature flame resistance of the specimen through additional surface coating was needed. In this study, multilayer coatings of YSZ and Al2O3 were performed on SUS 304 specimens using pack cementation coatings and thermal plasma spray. The multilayer coated specimen showed enhanced thermal properties due to the coated layers. The microstructures and phase stability are discussed together with flame conditions at 1350 ℃.

This study was conducted to explore the effects of seeding rate of a seed mixture on grassland productivity and botanical composition. Seeding rates were composed of four different treatments varying by the amount of seed: T1, 50% decrease in seeding rate from standard; T2, standard seeding rate; T3, 50% increase in seeding rate from standard; and T4, 100% increase in seeding rate from standard. In 2016, seasonal changes in grass botanical composition revealed T2, T3, and T4 in portion of grass ratio were the highest with a range of 87–100%, whereas T1 was the lowest of all treatments. In 2017, the botanical composition in T1 showed that the grass ratio in of the first cutting was 91%, but in the fourth cutting its ratio decreased by 75%. The results from both years were combined for each treatment, T4 (11,435 kg ha-1) and T3 (11,162 kg ha-1) demonstrated the highest dry matter yield of the treatments (T1: 8,196 kg ha-1; T2: 9,521 kg ha-1) (p＜0.05). As a result, a 50–100% increase in the seeding rate from the standard demonstrated the best grassland yield and botanical composition.

Recently, interest in the development of alternative water resources has been increasing rapidly due to environmental pollution and depletion of water resources. In particular, seawater desalination has been attracting the most attention as alternative water resources. As seawater desalination consumes a large amount of energy due to high operating pressure, many researches have been conducted to improve energy efficiency such as energy recovery device (ERD). Consequently, this study aims to compare the energy efficiency of RO process according to ERD of isobaric type which is applied in scientific control pilot plant process of each 100 m3/day scale based on actual RO product water. As a result, it was confirmed that efficiency, mixing rate, and permeate conductivity were different depending on the size of the apparatus even though the same principle of the ERD was applied. It is believed that this is caused by the difference in cross-sectional area of the contacted portion for pressure transfer inside the ERD. Therefore, further study is needed to confirm the optimum conditions what is applicable to the actual process considering the correlation with other factors as well as the factors obtained from the previous experiments.

Background: A limited hip rotational range of motion (ROM) has been considered to be one of characteristics of low back pain (LBP) in athletes. Although LBP frequently occurs in jiu-jitsu athletes, no previous has compared hip rotational ROM between jiu-jitsu athletes with and without LBP. Objects: The aim of the study was to compare ROM for hip internal rotation (IR) and external rotation (ER), and total hip rotation between jiu-jitsu athletes with and without LBP. Methods: Jiu-jitsu athletes were recruited for the LBP group (n1=15) and control group without LBP (n2=15). IR, ER, and total rotational range of hip joint were measured using a goniometer. Analysis of variance was used to compare the ROM between groups and sides. Results: The LBP group showed a significantly lower range of passive hip IR, passive total rotation, active IR, active ER, and active total rotation than the control group (p<.05). Dominant side of passive hip IR and active IR had a significantly lower ROM than non-dominant side (p<.05). In passive ER ROM, non-dominant side was significantly greater than dominant side (p<.05). Conclusion: Compared to jiu-jitsu athletes without LBP, athletes with LBP exhibit a loss of hip rotational ROM. Based on these results, clinicians and athletic trainers should measure hip rotational ROM when designing the management plan for jiu-jitsu athletes with LBP.

Pseudo-static approach has been conventionally applied for the design of gravity type quay walls. In this method, seismic coefficient (kh), expressed in terms of acceleration due to gravity, is used to convert the real dynamic behavior to an equivalent pseudo-static inertial force for seismic analysis and design. Therefore, the calculation of an appropriate kh considering frequency characteristics of input earthquake is critical for representing the real dynamic behavior. However, the definitions of kh, which is used for simplified analysis in Korea, focuses only on convenience that is easy to use, and the frequency characteristics of input earthquake are not reflected in the kh definitions. This paper evaluates the influences of the frequency characteristics of input earthquake on kh by initially reviewing the kh definitions in the existing codes of Japan for port structures and then by performing a series of dynamic centrifuge tests on caisson gravity quay walls of different earthquake input motions (Ofunato, Hachinohe). A review of the existing codes and guidelines has shown that the kh values are differently estimated according to the frequency characteristics of input earthquake. On the other hand, based on the centrifuge tests, it was found that the permanent displacements of wall are more induced when long-period-dominant earthquake is applied.

For the purpose of developing new immunomodulatory agents from broccoli, ethanol extract (BCEE), hot water extract (BCHW), and crude polysaccharide (BCCP) were isolated from broccoli, and their immunomodulatory activities and chemical properties were examined. In the in vitro cytotoxicity analysis, BCHW and BCCP did not affect the growth of tumor cells and normal cells. Murine peritoneal macrophages stimulated with BCCP showed higher production of IL-6, IL-12, and TNF- α cytokines than those stimulated with BCHW. Also, BCHW and BCCP did not show proliferation of splenic lymphocytes. In the in vitro assay for intestinal immunomodulatory activities, only BCCP enhanced GM-CSF secretion and the bone marrow cell-proliferating activity via cells in Peyer’s patches at 1,000 μg/mL. Also, BCHW mainly contained 33.7% neutral sugars, such as arabinose, glucose, and galactose, and 30.7% uronic acid, and BCCP consisted of 42.6% neutral sugars, including arabinose, galactose, and glucose, and 50.5% uronic acid. The above results lead us to conclude that crude polysaccharide (BCCP) isolated from broccoli causes considerably high cytokine production in peritoneal macrophages and bone marrow cell proliferation, and the polysaccharide extraction process is indispensable for separation of new immunomodulatory agents from broccoli.

In this study, it is estimated that ceramic membrane process which can operate stably in harsh conditions replacing existing organic membrane connected with coagulation, sedimentation etc. . Jar-test was conducted by using artificial raw water containing kaolin and humic acid. It was observed that coagulant (A-PAC, 10.6%) 4mg/l is the optimal dose. As a results of evaluation of membrane single filtration process (A), coagulation-membrane filtration process (B) and coagulation-sedimentation-membrane filtration process (C), TMP variation is stable regardless of in Flux 2 m3/m2･day. But in Flux 5 m3/m2･day, it show change of 1-89.3 kpa by process. TMP of process (B) and (C) is increased 11.8, 0.6 kpa each. But, the (A) showed the greatest change of TMP. When evaluate (A) and (C) in Flux 10 m3/m2･day, TMP of (A) stopped operation being exceeded 120 kpa in 20 minutes. On the other hand, TMP of (C) is increased only 3 kpa in 120 minutes. Through this, membrane filtration process can be operated stably by using the linkage between the pretreatment process and the ceramic membrane filtration process. Turbidity of treated water remained under 0.1 NTU regardless of flux condition and DOC and UV254 showed a removal rate of 65-85%, 95% more each at process connected with pretreatment. Physical cleaning was carried out using water and air of 500kpa to show the recovery of pollutants formed on membrane surface by filtration. In (A) process, TMP has increased rapidly and decreased the recovery by physical cleaning as the flux rises. This means that contamination on membrane surface is irreversible fouling difficult to recover by using physical cleaning. Process (B) and (C) are observed high recovery rate of 60% more in high flux and especially recovery rate of process (B) is the highest at 95.8%. This can be judged that the coagulation flocs in the raw water formed cake layer with irreversible fouling and are favorable to physical cleaning. As a result of estimation, observe that ceramic membrane filtration connected with pretreatment improves efficiency of filtration and recovery rate of physical cleaning. And ceramic membrane which is possible to operate in the higher flux than organic membrane can be reduce the area of water purification facilities and secure a stable quantity of water by connecting the ceramic membrane with pretreatment process.

Selecting suppliers in the global supply chain is the very difficult and complicated decision making problem particularly due to the various types of supply risk in addition to the uncertain performance of the potential suppliers. This paper proposes a multi-phase decision making model for supplier selection under supply risks in global supply chains. In the first phase, the model suggests supplier selection solutions suitable to a given condition of decision making using a rule-based expert system. The expert system consists of a knowledge base of supplier selection solutions and an “if-then” rule-based inference engine. The knowledge base contains information about options and their consistency for seven characteristics of 20 supplier selection solutions chosen from articles published in SCIE journals since 2010. In the second phase, the model computes the potential suppliers’ general performance indices using a technique for order preference by similarity to ideal solution (TOPSIS) based on their scores obtained by applying the suggested solutions. In the third phase, the model computes their risk indices using a TOPSIS based on their historical and predicted scores obtained by applying a risk evaluation algorithm. The evaluation algorithm deals with seven types of supply risk that significantly affect supplier’s performance and eventually influence buyer’s production plan. In the fourth phase, the model selects Pareto optimal suppliers based on their general performance and risk indices. An example demonstrates the implementation of the proposed model. The proposed model provides supply chain managers with a practical tool to effectively select best suppliers while considering supply risks as well as the general performance.

Recently, many studies on Mixed Reality have been going on. Virtual Reality can only show virtual objects, but Mixed Reality combines real-world information to open up more possibilities. In the game, interaction between the player and others is an essential factor, and games based on Virtual Reality or Mixed Reality using HMD are no exception. For this, we implemented a Mixed Reality System for the Behavior-like Interaction using an additional device to HMD that supports Virtual Reality. This paper presents the theoretical content, the overall contents of the implemented Mixed Reality System, the experiment, the evaluation, and the results.

전극 구성에 따른 고효율 전해정련공정의 일반적인 모델을 구축하기 위하여, 상미분방정식 인터페이스를 갖는 COMSOL Multiphysics V5.3 전착 모듈을 사용하여 수치해석을 실시하였다. 구축된 모델은 한국원자력연구원에서 제작한 실험실 규 모 (1kg 우라늄/day 규모) 다중배열전극 전해정련장치를 사용해 전극 간 거리, 전극 배열을 변수로 하여 실시한 실험의 전 류밀도-전위 곡선과 비교하였다. 공정온도는 500℃이다. 용융염은 3wt% UCl3가 포함된 LiCl-KCl 공융염을 사용하였다. 검 증된 모델을 이용하여 전류밀도-셀전위 곡선을 계산한 결과 전극 간 거리가 가까울수록, 전극 배열은 양극/음극 면적비가 증 가할수록 셀 전위가 낮아져 전해정련장치의 우라늄 처리효율을 향상시킬 수 있다는 것을 확인하였다. 이러한 접근은 고출력 사용후핵연료 전해정련기의 안전설계를 위한 데이터베이스 구축에 유용할 것이다.

Si3N4 is a ceramic material attracting attention in many fields because of its excellent abrasion resistance. In addition, Ti and TiAl alloys are metals used in a variety of high temperature environments, and have attracted much attention because of their high strength and high melting points. Therefore, study of the interface reaction between Si3N4 / Ti and Si3N4 / TiAl can be a useful practice to identify phase selection and diffusion control. In this study, Si3N4 / Ti5Si3 + TiN / TiN / Ti diffusing pairs were formed in the Si3N4 / Ti interfacial reaction and Si3N4 / TiN(Al) / Ti3Al / TiAl diffusion pathway was identified in the Si3N4 / TiAl interfacial reaction. The diffusion layers of the interface reactions were identified and, to investigate the kinetics of the diffusion layer, the integrated diffusion coefficients were estimated.

목적: 청색광 차단 안경렌즈 착용 전과 후의 대비감도 시력을 평가하고자 한다. 방법: 성인 남녀 37명을 대상으로 원거리 시력을 교정한 상태에서 청색광 차단 안경렌즈 착용 전과 후의 원거리와 근거리 양안 대비감도 시력을 측정하였다. 원거리 양안 대비감도 시력의 측정은 10% Lea-numbers 대비감도 시표(Good-LITE, USA)를 사용하였고 근거리 양안 대비 감도 시력의 측정은 adobe illustrator cs6을 이용하여 40cm 5% 근거리 대비감도 시표를 제작 하여 측정하였다. 측정에 사용된 청색광 차단 안경렌즈는 D, S, C, N社의 제품을 사용하였다. 검사실의 조도는 500lx 이었다. 결과: 청색광 차단 안경 착용 전 원거리 10% 양안대비감도시력은 -0.0558± 0.1887 LogMAR, 청색광 차단 안경 착용 후의 양안대비감도시력은 C社 -0.0849±0.168, N社 -0.070±0.164, S社 -0.0576±0.1985, D社 -0.0394±0.1853 LogMAR 순이었으며, 이원분산 분석 결과 통계적 유의성은 없는 것으로 나타났다. 또한 5% 근거리 대비감도 시력은 0.26± 0.1726 LogMAR, 청색광 차단 안경 착용 후의 양안대비감도시력은 N社 0.242±0.1396, D社 0.263±0.1853, C社 0.267±0.135, S社 0.282±0.1985, LogMAR 순이었으며, 이원분산분석 결과 유의성은 없는 것으로 나타났다. 결론: 청색광 차단 안경렌즈는 우리 눈에 유해하다고 알려진 청색광을 일부 차단하기 때문에 전체 가시광선 투과율이 낮아져 대비감도에 영향을 줄 것으로 생각하였다. 그러나 현재 시판중 인 청색광 차단 안경렌즈는 원거리, 근거리 대비감도 시력의 변화에 큰 영향을 주지 않으면서 유해광선을 차단하는 것을 확인 할 수 있었다.

수소는 고부가가치의 신재생 수송원료이자 탄소자원화 화학제품 제조의 기초 원료로 사용할 수 있으며 이를 위해 경제성 있는 분리소재 및 분리공정기술이 중요하다. 본 연구에서는 철강부생가스 COG내 수소를 회수할 수 있는 건습식 방사법에 의한 비대칭 구조의 폴리이미드 중공사막의 제조를 연구하였다. 이를 위해 지환족 다이안하이드를 사용한 유기용매에 대한 용해성이 높은 폴리이미드 소재를 합성하여 수소, 메탄, 질소, 산소 등의 기체투과특성을 확인하였고 그 중 가장 수소 선택성이 높은 DOCDA-ODA를 이용하여 용해성 폴리이미드를 합 성하였다. 합성된 폴리이미드는 H-NMR, FT-IR을 통하여 합성이 성공적으로 이루어진 것을 확인하였으며 확보된 폴리이미드를 이용해 건습식 방사법에 의한 중공사막을 제조하였다.

This study is aimed to separation propylene and propane using membrane process. Membrane-based gas separation enables a chemical process to be low-energy consuming, if high olefin selective membrane is developed. In this study, facilitated transport membrane (FTM) is used for propylene/ propane separation. We prepared FTM module using PVP/AgBF4/TCNQ composite membrane on top of hollow fiber membrane. We developed simulation program predicting the membrane separation properties under operation conditions. Separation properties of FTM module for propylene and propane were obtained from the simulation program based on the pure gas permeation data. Based on the these results, it is predicted that an one-stage membrane process provides 99.5% of propylene at permeate side from a binary gas mixture of 95 vol% C3H6/5 vol% C3H8 supplied as a feed gas.

프로필렌은 석유화학제품의 기초 연료이며, Naphatha Cracker 에서 나오는 프로필렌/프로판 혼합물을 저온증류하여 생산된다. 저온증류를 이용하여 프로 필렌/프로판을 분리할 경우 많은 에너지가 소비되기 때문에 플랜트 규모가 작고 에너지 소비가 적은 막분리법이 대체법으로 연구되고 있다. 본 연구에서는 올레핀/파라핀 분리에 우수한 성능을 가지는 아민계 고분자를 이용하여 촉진수 송막을 제조하였으며, 이들의 프로필렌/프로판 분리특성을 알아보았다. 순수가 스 테스트를 통해 압력변화에 따른 투과도와 선택도를 구하였으며, 혼합가스 테 스트를 통해 stage-cut에 따른 투과측 프로필렌 농도 및 회수율 변화를 알아보 았다. 그 결과, 2bar, 25°C에서 95%의 프로필렌을 99.6%까지 농축 시킬 수 있음을 확인하였다.