Strain Distributions of Plane-Strained and Simple-Sheared Al–Mg Alloy

Hyeon‑Woo Son,Jae‑Cheol Lee,Hyun Soon Park,Soong‑Keun Hyun 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.11

Strain distribution in plane-strained (rolling) and simple-sheared (torsion) Al–Mg alloy has been estimated using both X-rayline profile analysis and electron backscatter technique. The strain analyses under unified texture distribution by orientationrotation showed that torsion has relatively homogeneous strain distribution regardless of texture component in contrast toinhomogeneous strain in rolling. In addition, annealing texture of torsion has more random texture than inhomogeneousrolling texture. Lower texture difference index in annealed torsion specimens suggest homogeneous strain distribution insimple shear has a higher resistance to strain-induced boundary migration, which has been known to be main reason forstrong development of ND||⟨100⟩ component during annealing of rolled Al sheet.

이방성 담낭(Bicameral Gallbladder) : 1례 보고

이현경,오연희,김승현,이성우,안우섭 동국대학교 경주대학 1996 東國論集 Vol.15 No.-

담낭의 선천성 기형 중 이방성 담낭은 매우 드문 기형으로 저자들은 우상복부 동통을 주소로 내원하여 초음파, 전산화 단층 촬영, 간담도 스캔 검사에서 이방성 담낭으로 진단되고 수술로 확진된 이방성 담낭(Bicameral GB) 1례를 경험하였기에 문헌 고찰과 함께 보고 하고자 한다. The bicameral gallbladder is one of the rarest congenital malformation of the gallbladder. A 26 years-old male was examined for the colicky pain in right upper quadrant area. On sonographic examination the lumen of gallbladder was partitioned, nearly completely, into two chamber(fundal and ductal) that are of approximately equal size. There was gallbladder wall thickening with cholelithiasis in the fundal chamber. Surgical finding showed bicameral gallbladder divided into two camber of same size and gallbladder wall thickening with cholelithiasis in the fundal chamber.

텅스텐인산으로 개질된 SBA-15 촉매 상에서 아세트산의 탈수반응

우창수,He, Nong-Yue,김현국,이호인 한국공업화학회 2004 응용화학 Vol.8 No.1

TPA (tungstophosphoric acid), a typical heteropoly acid, was impregnated on SBA-15 to modify the acidic property of the mesoporous catalyst. The TPA was highly dispersed on the SBA-15 which has large surface area confirming by nitrogen adsorption, X-ray diffraction, and infrared spectroscopy. According to the result of in-situ FTIR spectroscopy using pyridine as a probe molecule, it was revealed that silanol group was gradually decreased with increasing the loading amount of TPA, and that new acidic site different from that of pure TPA was generated resulting in the enhancement of catalytic activity. TPA could act as a promoter when loaded on SBA-15 by relatively small amount, but the catalytic activity was greatly decreased due to the loss of silanol group as an active site when a large amount of TPA was loaded.

최단경로 알고리즘을 이용한 PCB 자동 배선에 관한 연구

우경환,김현호,이천희 청주대학교 산업과학연구소 2001 産業科學硏究 Vol.19 No.1

Routing region modeling methods for auto-routing system is used grid and non-grid methods Although physical elements are small, the grid method has disadvantage that decrease the auto-routing speed due to constraint with size of grid and board, which in it is increase memory size Shape based type(non-grid method) used region process type and the shape located in memory as a individual element, and this element consumed small memory due to unique data size In this paper we developed PCB(Print Circuit Board) auto-routing system using the auction algorithm method that 1) Could be reached by solving the shortest path from single original point to various destination, and 2) without any memory dissipation with the best speed. Also, the auto-routing system developed by Visual C++ in Window environment, and can be used in IBM Pentium computer or in various individual PC system

스트룹 테스트와 단순반응 테스트의 훈련 향상도에 관한 연구

조현우,박영민,박사엘,공추,왕초전,장신,김재화 순천향대학교 기초과학연구소 2022 순천향자연과학연구 논문집 Vol.28 No.1,2

This study which of the Stroop test training and simple response training can reduce the Stroop effect in the information processing process when continuous training is performed. 4 male students from S University(Asan-si) were divided into Stroop test training group(2) and simple reaction group(2). The test was conducted 10 times a day, and average was obtained and analyzed. The results encountered through this study are as follows. 1 The simple response training group improved more slowly than the Stroop test training group. 2. In the Stroop test training group, the rate of increase increased significantly compared to the simple response training group, but it did not increase once the record reached a certain point. 3. Simple response training at increasing values ​​was also trained on the Stroop effect. 4. In the average of phage values, both groups look similar.

청감실험을 통한 교통소음의 주관적 반응 조사

박현구,조경숙,송혁,김선우 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1

The aim of this study is to analyse the relationship between traffic noises and subjective responses. The traffic noises considered in this study were aircraft, road traffic and train, and we recorded them in order to edit by using the sound insulation performance of windows. The sound sources recorded and edited were made to be different sound level with 5 steps by 5dB. Finally 100 sounds sources were composed for the purpose of psychoacoustic experiments and we surveyed the subjective responses. As a result, the average points of the subjective response to the sound sources have shown differently depending on their sound level, the type of windows and the type of sound sources.

췌장 손상의 CT진단

이현경,이성우,오민구 동국대학교 경주대학 1998 東國論集 Vol.17 No.1

수술 또는 임상 소견으로 췌장 손상이 진단된 34명의 환자를 대상으로 하여 손상 직후 시행한 전산화단층촬영 소견을 후향적으로 분석하였다. 전산화단층촬영 소견상 췌장 실질 손상의 유무, 췌장 주위 액체 저류의 유무 및 위치, 전신막 비후, 동반된 장기 손상등을 알아 보았다. 34명의 췌장 손상 환자중 전산화단층촬영 소견상 췌장 실질내 병변이 관찰된 예는 22명(65%)이었고 췌장 주위 액체 저류가 관찰된 경우는 2명을 제외한 32명(94%)이었다. 액체 저류의 위치는 전신방강이 20예(59%)로 가장 많았고, 소낭이 16예(47%), 췌장과 비정맥 사이 14예(41%), 상장간막 정맥 및 동맥 주위 9예(26%), 위십이지장동맥 주위 1예(3%)였다. 전신막의 비후는 19예(56%)에서 보였다. 췌장 손상 환자의 35%에서 전산화단층촬영상 췌실질 손상이 관찰되지 않았고 췌장 주위의 액체 저류는 2예를 제외한 전례에서 관찰되었다. 그러므로 췌장 주위의 액체 저류를 관찰하는 것은 췌장 손상이 의심되는 환자에서 실질내의 손상 소견이 관찰되지 않거나 의심스러울 시 진단에 도움이 되는 유용한 소견으로 생각된다. We retrospectively reviewed the abdominal CT scans of 34 patients with surgically proven pancreatic injury or clinical pancreatitis after blunt abdominal trauma. The CT scans were analyzed for the pancreatic gland injury, presence and location of the peripancreatic fluid collections, Thickening of the anterior renal fascia, and associated injury. The pancreatic injury was identified on CT in 22 patients(65%), whereas peripancreatic fluid collections on CT were noted 32 patients(94%) who had pancreatic injury. The fluid was in the anterior pararenal space in 20 patients(59%), in the lesser sac in 16 patients(47%), between the pancreas and the splenic vein in 14 patients(41%), around the SMA & SMV in 9 patients(26%), and around the gastroduodenal artery in 1 patient(3%). Thickening of anterior renal fascia was seen in 19 patients(56%). Pancreatic injury was not observed on CT in 35% of patients with such injury, whereas peripancreatic fluid collections on CT were noted in 94% who had pancreatic injury. The presence of peripancreatic fluid is a helpful CT finding for the diagnosis of pancreatic injury after blunt abdominal trauma.

알루미늄과 헤테로폴리산으로 개질된 메조포러스 실리카 상에서의 AKD 합성

김현국,우창수,최재석,박민태,이병민,이호인 한국공업화학회 2003 응용화학 Vol.7 No.1

AKD(alkyl ketene dimer) used widely as a neutral sizing agent is produced industrially by halogenization of stearic acid followed by dimerization of alkyl ketene. In the present work, to suppress the byproduct of hydrochloric acid and to improve reaction pathway. AKD was prepared through of ketene intermediate by dehydration of stearic acid in gas phase using reaction with silanol on silica as active sites of the catalyst SBA-15 showed the highest activity due to the large and open tubular pores. It was found that main products were dimer and trimer. Our goal of the present work was to increase of the selectivity for the dimer.

미국정당의 도전과 변화

이현우 서강대학교 사회과학연구소 2003 社會科學硏究 Vol.11 No.-

1960년대 미국에서 흑인들을 중심으로 민권운동이 일어나면서 뉴딜연합으로 구성된 정당체계의 변화가 나타나기 시작한다. 그 대표적인 것이 유권자들이 새로운 이슈에 의해 재편되는 것이 아니라 정당에 대한 소속감이 감소하는 유권자 연합의 해체현상이라고 볼 수 있다. 이러한 현상을 가장 직접적으로 보여주는 것이 무당파(independents)의 증가와 투표시 분할투표(split-ticket voting)의 경향이 강하게 나타나는 것이다. 미국정당의 약화요인으로는 첫 번째가 정당의 고유기능의 약화이다. 정당이 후보자를 충원하고 공천하는 기능을 하는데 미국에서 정당개혁을 통해 후보자 공천과정이 일반인에게 공개되면서 정당의 영향력이 감소된 것이다. 두 번째 원인으로 들 수 있는 것이 대중매체의 발달이다. 미국의 정당활동이 주로 선거를 중심으로 이루어지는데 TV 등 대중매체의 발달은 정당보다는 후보자 중심의 선거운동으로 이루어지게 되었다. 미국의 정당개혁은 1910년대와 1970년대에 이루어졌다. 그러나 정당개혁은 정당의 민주화와는 연결되었지만 정당의 발전을 정당의 강화라는 의미에서 본다면 성공적이라고 할 수는 없었다. 정당의 전당대회는 이미 선출된 후보를 확인하는 이상의 의미는 갖지 못하게 됨으로써 정당의 기능을 약화시키게 된 것이다. 이는 결국 정당의 책임성이 약화되고 후보자의 영향력이 강화되었다는 것을 의미하게 된다. 후기산업사회에서 대두되는 다양한 문제들로 유럽에 서도 기존정당을 비판하면서 새로운 정당이 등장하는 것을 보면(장훈 1994) 미국에서도 사회의 복잡화로 인하여 정당에 대한 유권자의 불만이 많아지는 일부 이유를 설명할 수 있다. Civil right movements in 1960s brought about the new political party system from the old one based on New Deal coalition. Unlike the previous coalitions, Change of the party system in 1960s was characterized by dealignment rather than realignment. That is, influence of the parties has been declined in that the number of independents and split-ticket voting increases. At least two points are mentioned to explain weakness of American political parties. First, the role of parties in selection of candidates became less critical because the nomination process was opened to party members through the party reforms. Second, increase of power of mass media is referred. Election campaign using mass media such as TV is more likely to pay attention to candidates rather than parties. Party reforms in U.S. were achieved in 1910s and 1970s. Even though the reforms contributed to democratization of running parties, it should pay to make the parties mainly controlled by amateurs, ranks and files. For example, National convention has simply confirmed the decisions by mass political members. As the results, the responsibility of parties becomes weak and candidate factors in elections are more counted. In one sense, the traditional concepts of political parties cannot be an answer for various conflicts in the post-material society. It is time to redefine the role of political parties to respond to the changing environments.

Enterococcus faecalis 추출물이 임파구의 IL-2, IL-4, TGF-β1분비에 미치는 영향에 관한 연구

김현식,이우철,손원준,이상탁,김철호,임성삼 大韓齒科保存學會 2005 Restorative Dentistry & Endodontics Vol.30 No.1

In order to examine the immunoresponse of host cells to Enterococcus faecalis, this in vitro study monitored the production of Interleukin-2 (IL-2), Interleukin-4 (IL-4) and Transforming growth factor-β1 (TGF-β1) in human lymphocytes. Lymphocytes were activated with PHA in the presence or abscence of sonicated extracts of E. Faecalis (SEF) and further incubated for 72 hours. The level of each cytokine was measured by ELISA. Data were analyzed with Kruskal-Wallis test and Mann-Whitney U test (P < 0.05). PHA-activated group did exhibit higher level of IL-2 and IL-4 than untreated control group. The levels of expression of both cytokines were significantly decreased following the treatment of high (25㎍/㎖) and medium concentration (12.5㎍/㎖) of SEF (P > 0.05) than those of PHA activated group. But low concentration (5㎍/㎖) of SEF showed th similar level of IL-2 and IL-4 production as those of PHA activated group. TGF-β1 was unaffected by SEF treatment. These results suggested that E. faecalis may suppress IL-2 and IL-4 production by lymphocytes and this could be one of possible factors why E. faecalis are found frequently in the teeth with failed endodontic treatment. 근관치료의 실패원인 중 중요한 세균으로 알려진 Enterococcus faecalis는 최근에 중요성이 더해지며 많은 연구들이 진행중이다. 여러가지 기전들이 보고되고 있으나 면역반응에 관한 연구는 거의 알려져 있지 않은 상태이다. 본 연구에서는 Enterococcus faecalis의 초음파 분쇄 추출물을 성인의 말초혈액으로부터 얻은 임파구에 적용시켜서 여기서 분비되는 interleukin-2, interleukin-4, transforming growth fater-β1의 농도를 Enzyme linked immunosorbent assay (ELISA)로 측정하여 비교, 평가하는 것을 목적으로 한다. E. faecalis를 적절한 조건에서 배양한 뒤 초음파 분쇄를 하여 추출물을 얻어냈다. 임파구는 건강한 성인의 말초혈액에서 추출하여 분리하였다. 임파구를 적절한 농도의 mitogen (Phytohemagglutinin: PHA)으로 자극시킨 뒤에 다양한 농도의 E. faecalis 초음파 추출물을 적용시키고 72시간 동안 배양하였다 ELISA를 이용하여 IL-2, IL-4,TGF-β1 의 농도를 측정하였다. 실험결과는 Kruskal-Wallis test, Man-Whitney rank sum test (p < 0.05)를 사용하여 통계처리 하였다. 실험결과 PHA로 처리한 군은 아무것도 처리하지 않은 군에 비해서 IL-2, IL-4의 수치가 유의성 있게 높았다 (p < 0.05). PHA로 처리한 군중에서 고농도와 중농도의 sonic extract of E. faecalis (SEF)로 처리한 군은 그렇지 않은 군에 비해서 IL-2 IL-4의 농도가 유의성 있게 낮았다 (p < 0.05). PHA로 처리한 군중에서 저농도의 SEF로 처리한 군은 그렇지 않은 군과 비교하여 유의할 만한 차이를 보이지 않았다.TGF-β1의 농도는 모든 군에서 유의할 만한 차이를 보이지 않았다 (p > 0.05). 따라서, E. faecalis의 추출물은 임파구의 IL-2, IL-4의 분비능력을 저하시킨다고 할 수 있다.