Correlation Between Primary Si and Silicide Refinement Induced by Ultrasonic Treatment of Multicomponent Al–Si Alloy Containing Ti, Zr, V, and P

Jae‑Gil Jung,Young‑Hee Cho,Tae‑Young Ahn,Jae‑Hee Yoon,Sang‑Hwa Lee,Jung‑Moo Lee 대한금속·재료학회 2019 METALS AND MATERIALS International Vol.25 No.5

The correlation between primary Si and silicide refinement induced by ultrasonic treatment (UST) of multicomponent Al–Sialloy containing Ti, Zr, V, and P was investigated. UST significantly refined the primary Si phase owing to cavitation-inducedwetting and deagglomeration of MgAl2O4particles. Lowering the UST finish temperature caused deterioration of the degreeof primary Si refinement, instead leading to silicide refinement. Cavitation-induced silicide nucleation on wetted MgAl2O4consumed the MgAl2O4particles, particularly in the case of primary Si nucleation. Similarly, the formation of an AlP phaseon the silicide phase reduced the nucleation efficiency of the AlP phase. Poisoning of the MgAl2O4and AlP phases by thesilicide phase was responsible for the deterioration in primary Si refinement. Room-temperature tensile strength and hightemperatureelongation were increased by UST and were dependent on the size of primary Si.

양주 노고산(老姑山) 독재동(篤才洞)의 장소성과 역사문화경관 해석

노재현 ( Jae Hyun Rho ),김화옥 ( Hwa Ok Kim ),이정한 ( Jung Han Lee ),박주성 ( Joo Sung Park ) 한국전통조경학회 2015 한국전통조경학회지 Vol.33 No.1

본 연구는 경기도 양주시 장흥면 삼하리 독재동 바위글씨와 노고산의 장소성에 주목하여, 이곳의 경관 및 장소특질을 고찰하고 바위글씨에 담긴 경관의미를 추론함으로써 노고산과 독재동 계곡의 역사문화경관적 함의를 밝히고자 한 것으로 연구 결과는 다음과 같다. 삼각산은 조선왕조 6백년 도읍지의 주산(主山)이며 오악(五嶽)을 이루는 중앙의 성산(聖山)으로, 노고산은 삼봉산(三峰山)즉 삼각산의 우람한 세봉우리를 향배하는 의미공간으로서 그 장소성이 획득된다. 더불어 노고산은 조선의 정기를 상징하는 삼각산을 가장 완벽하게 조망할 수 있는 ‘망삼각산(望三角山)’의 절대 시점장이다. 독재동 계곡에 산포(散布)된 다수의 바위글씨는 미수 허목의『고양산수기』의 내용을 현현(顯現)하기 위한 행위이자 경물로 재생산된 산물이다. 그리고 추사 필적의 몽재(夢齋)는 중의적(衆意的) 표현이 읽혀지는 바위글씨로, 먼저 글자 그대로의 뜻인 ‘꿈꾸는 집’ 이지만 내면적 의미는 “한낮 몽상(夢想)도 바탕을 깊이 헤아려 보면 정당성이 확보된다.”는 의미로 ‘몽재거사’로 알려진 성재(性齋) 허전(許傳)의 『몽재집(夢齋集)』서(序)의 내용으로 보아 성재의 독재동 거주와 관련된 징표로 추정된다. 또한 몽재라 쓴 바위 하단의 갑자(甲子)·경오(庚午)·무술(戊戌)·갑인(甲寅) 등의 간지(干支)는 추사와의 교유관계가 있는 1804년 5월생 유생(儒生)의 사주팔자로 판단된다. 노고산과 독재동 계곡은 삼각산을 조망하는 장소일 뿐 아니라 송월재·성재 등 미수의 학통을 계승한 기호지역의 남인학자의 공통된 장구지소로써의 응집력을 보여준다. 또한 이곳에 각자(刻字)된 추사체와 미수체(전서체) 바위글씨는 우리나라 서예사의 큰 흐름을 함축적으로 보여준다는 측면에서도 매우 의미 깊은 역사문화경관이다. This study was focused on the placeness of Nogosan Dokjae-dong and rock inscription located in Jangheung-myeon, Yangju-si, Gyeonggi-do. The purpose was to reveal the implication of Nogosan and Dokjae-dong Valley in terms of Historic cultural landscape by considering the characteristics of the place and its landscape, and inferring the significance of the letters engraved on the rock. The result is as follows.10)Samgaksan is one of the five famous mountains in Korea. It is the sacred mountain that stands behind the capital city of the Joseon Dynasty that lasted for 600 years. On the other hand, the placeness of Nogosan is significant since it was the place where people used to bow low to the three great summits of Samgaksan. Furthermore, Nogosan was the perfect place to view Samgaksan that represented the Joseon spirit.Many letters were engraved on the rocks around Dokjae-dong Valley by Misu(眉수) Heo Mok(許穆) as part of his memories to describe his experience in the mountain and became a scenery. Chusa(秋史) Kim Jung-Hee(金正喜) also engraved letters of ``Mongjae`` on the rock that contains a double meaning. Literally, it means ‘a dreaming house’ However, it also implies that even just a daydream is significant in a way. These letters are presumed to be the signs that are related to Sung-Jae(性齋) Heo Jeon(許傳)’s experience in Dokjae-dong since the letters were part of his famous book title. Below these two letters, Chusa also engraved letters that describe the sexagenary cycle including the year of the rat, horse, dog, and tiger. They are regarded as the letters that describe the fate of Chusa’s friend, a scholar born in May 1804. Nogosan and Dongjae-dong Valley are very significant in terms of historic cultural landscape as a viewpoint to see Samgaksan; and a place that cherishes the traces of Misu and shows common values and cohesiveness of well-known scholars of the Joseon Dynasty including Song Wol-Jae(松月齋) and Sung-Jae as a of Gihonamin(畿湖南人). The engraved letters of Chusa and Misu also implicitly demonstrates the major trends of Korea’s calligraphy history.

2003년 국내 중증급성호흡기증후군 진료 현황 및 문제점 분석

이진수,김은실,정문현,백제중,정선화,안주희,최영화,이선희,고철우,김성범,김민자,박승철,기현균,송재훈,최상호,김양수,이상오,조용균,박영훈,정숙인,김연숙,이흥범,손창희,장성희,정희진,김우주 대한감염학회 2004 감염과 화학요법 Vol.36 No.3

목적 : 2002년 말 중국에서 SARS가 발생한 이후 국내에서도 2003년 10월까지 총 3명의 추정환자, 17명의 의심환자가 보고되었다. 향후 추가적인 SARS의 유행이 우려되는 상황에서, 그간의 SARS 환자 진료에 있어서의 실질적인 준비사항, 진료 현황 등에 대한 조사를 통해 문제점을 파악하여, 향후 더 나은 대비가 될 수 있도록 개선점을 제시하고자 하였다. 재료 및 방법 : SARS로 의심되는 환자를 진료 경험이 있는 병원의료진을 대상으로 2003년 10월에 설문조사를 실시하였다. 설문에는 SARS 환자 진료 시의 실질적인 조치, 진료 현황, 병실, 응급실 및 외래에서의 격리 시설과 준비사항, 보건당국의 관리와 지원에 관한 사항을 포함하였다. 결과 : 대상이 되는 22개 병원 중 17개(17/22, 77.2%) 병원이 설문에 응하였다. SARS 환자를 위한 격리실은 응급실, 외래, 일반병실 및 중환자실에서 각각 9개(9/17, 52.9%), 5개(5/17, 29.4%), 15개(15/16, 93.7%), 4개(4/16, 25%) 병원에서 음압처리가 되어있지 않은 일인실 혹은 다인실이 사용되었고, 1개(1/16, 6.3%) 병원에서만 일반병실에서 음압격리실이 운영되었다. 입원환자의 진찰 시 개인보호구의 착용은 거의 모든 의료기관에서 이루어졌다. 보건당국에서 SARS지정병원의 시설 등을 사전에 확인한 곳은 1곳(1/12, 8.3%)이였고, 14개 병원(14/15, 93.3%)에서는 보건당국에 의뢰한 검사결과를 통하 받지 못하였다. 결론 : 의료기관에서 SARS 환자용 격리실뿐만 아니라 기존의 격리실 설비 등이 미흡하였으며, 특히 중환자실 및 외래의 준비가 더욱 부족하였다. 보건당국의 의료기관에 대한 종합적인 지원이 부족하였고, 병원과의 원활한 연계가 잘 이루어지지 않았다. SARS 만이 아닌 격리를 필요로 하는 질환의 적절한 진료를 위해 향후 병원 시설의 정비와 정부차원에서의 보다 구체적이고 실질적인 대책마련이 필요하다. Background : There was an worldwide outbreak of the Severe Acute Respiratory Syndrome (SARS) originated from China in late 2002. During that period three cases of suspected SARS and 17 cases of probable SARS were reported in Korea. With the concerns about the reemergence of SARS-coV transmission, it is important to be prepared for any possibility. So, this study is aimed to analysis the past measures in managing SARS and propose the amendatory plans to improve the preparedness. Materials & Methods : Questionnaires were collected among clinicians with any experience in managing the probable or suspected SARS cases in Oct. 2003. 17 out of 22 hospitals responded to the questionnaire. The contents in the questionnaire were practical activities, personal equipments, response plans, isolation facilities in emergency centers, outpatient clinics, general wards and intensive care units, and relationship with the public health department. Results : The dedicated isolation rooms in emergency centers, outpatient clinics, general wards, and intensive care units were prepared in 9 (9/17, 52.9%), 5 (5/17, 29.4%), 15 (15/16, 93.7%), and 4 (4/16, 25.0%) hospitals, respectively. Except for one hospital that newly made negative pressure room for SARS, single or multi-bed rooms without airborne infection control were used in all the other hospitals. The personal precaution principles were kept quite well in general wards. Before the designation of SARS hospital by the public health department prior evalution to see if the hospital was suitable for managing SARS was conducted in only 1 (1/12, 8.3%) hospital. The results of laboratory diagnosis were reported back in 1 (1/15, 6.6%) hospital. Conclusions : The isolation facilities which can control airborne infection were almost deficient not only for SARS but also for other respiratory transmissible diseases. For the infection control of transmissible diseases including SARS, more investment is needed on medical facilities and comprehensive support from the public health department required.

국내 5개 3차 병원의 β-lactam계 항생제 사용 실태 및 Klebsiella pneumoniae의 항생제 내성과의 상관 관계

정숙인,박경화,권기태,고관수,오원섭,정두련,백경란,염준섭,장현하,김신우,손준성,송재훈 대한감염학회 2007 감염과 화학요법 Vol.39 No.4

Background : This study was performed to evaluate the prescribing pattern of β-lactam antibiotics and the relationship between antimicrobial resistance and antimicrobial use in 5 tertiary care hospitals in Korea. Materials and Methods : Data on annual patient-days and annual consumption (defined daily dose (DDD) per 100 patient-days) of β-lactam antibiotics from 2003 to 2005 in 5 tertiary hospitals were analyzed. To determine the antimicrobial resistance in K. pneumoniae, broth microdilution test and double disk synergy were performed according to the CLSI performance standards. Spearman's correlation coeffient was used to determine the relationship between antibiotic consumption and resistance. Results : The prescription of β-lactam antibiotics in 5 tertiary hospitals markedly varied. In two hospitals, increase in consumption of β-lactam antibiotics was more than 30% during recent 3 years. The higher consumption of β-lactam antibiotics significantly correlated with the higher rate of antibiotic-resistant K. pneumoniae in 5 tertiary care hospitals. Conclusion : Continuous surveillance of antibiotic use is needed to encourage appropriate prescribing of antibiotics and to reduce antibiotic resistance. 목적 : 항생제의 오남용으로 인한 내성균의 발현 및 급속한 확산이 전세계적으로 문제시 되고 있다. 특히 병원은 항생제 내성의 중심점에 있는 것으로 여겨진다. 본 연구에서는 최근 3년간 국내 5개 3차 병원의 β-lactam계 항생제의 사용량을 조사하고, 각 병원별 항생제 사용량과 K. pneumoniae의 항생제 내성률과의 상관관계를 알아보고자 하였다. 재료 및 방법 : 국내 5개 3차 병원에서 2003년 1월부터 2005년 12월까지 병원 입원 환자를 대상으로 연도별 재원연인원수와 각 β-lactam계 항생제의 총사용량을 수집하여 DDD (defined daily dose) per 100 patient-days로 환산하여 비교하였다. 2005년 6월부터 8월까지 각 병원의 임상검체에서 동정된 K. pneumoniae를 수집하여 액체배지미량희석법으로 항생제 감수성 검사를 시행하였고 ESBL(extended-spectrum β-lactamase) 생성 여부는 double disk synergy test를 시행하였다. 항생제 사용량과 내성의 상관관계는 Spearman 상관관계 분석을 시행하였다. 결과 : 5개 병원 중 3개 병원에서는 연도별 β-lactam계 항생제 사용량이 비슷하게 유지되었으나, 2개 병원에서는 2003년에 비해 2005년에 항생제 사용량이 30% 이상 증가하였다. β-lactam계 항생제 중 제제별 비율은 각 병원마다 차이가 있었으나, 3세대 cephaosporin의 사용이 가장 많았고 2세대 ceaphlosporin, β-lactam/β-lactamase inhibitor, 1세대 cephalosporin 순이었다. 경구용 β-1actam계 항생제의 사용량(r=0.900, P<0.037)과 2세대 cephalosporin의 사용량(r=0.900, P<0.037)은 각각 K. pneumoniae의 ESBL 생성과 양의 상관관계가 있었다. Ceftazidime의 사용량은 K. pneumoniae의 ceftazidime 내성률과 양의 상관관계가 있었다(r=0.900, P<0.037). 반면 imipenem의 사용량은 piperacillin/tazobactam 내성과 음의 상관관계가 있었다(r=-0.900, P<0.037). 결론 : 최근 3개년간 항생제 사용량은 병원별로 차이가 있으나 일부 병원에서는 증가하였다. β-lactam계 항생제의 사용량은 K. pneumoniae의 항생제 내성과 상관관계가 있었다. 항생제 사용을 줄임으로써 항생제 내성을 감소시킬 수 있을 것으로 기대되며, 병원별로 항생제 사용에 대한 지속적인 감시가 필요할 것이다.

中小都市의 成長要因과 特性에 관한 實證的 考察

정영동,오재화,김우혁,송승헌 朝鮮大學校 建設技術硏究所 2000 建設技術硏究 Vol.20 No.1

The study is concerned with all small and medium size cities. Study on the major purpose is to identify the domanial factors and their change for the growth of small and medium size cities through the analysis of correlation with growth rate. It could be done by case study of growth trends of all existing small and medium size cities for analysis period. The analysis results are summarized as follow : 1. Inevitably, the classification standards of the small and medium sized level in an urban hierarchy may vary among countries, depending on their pattern of urban settlement, level of development, and economic structure, population density, etc. But, the most convenient and frequently used criterion for identifying small and medium sized cities is relative population size because the city is proportional to the functional complexity. 2. The major factors affecting growth of small and medium size cities are POP, FIN, HIS, i.e., in 1986's. and the most dominant factor among them is POP, and The major factors affecting growth of small and medium sized cities are HIS, SAC, ASS, i.e., in 1996's, and the most dominant factor is HIS. 4. As the result, in small and medium size cities three variables, i.e., POP, HIS, SAC-are selected as the general factors concerned with urban population growth.

이종 탈회 건조골 및 Hydroxyapatite 제재의 골 이식이 성견 치조골 결손부 치유에 미치는 영향에 관한 비교연구

정성화,김종여,이재현 단국대학교 치의학연구소 1993 논문집 Vol.5 No.-

This study was conducted to evaluate the healing potential of hydroxyapatite and demineralized freeze dried bone in 5 dogs. Chronic periodontitis was induced by ligating elastic wire randomized as follows. The group in which only flap operation was performed was used as control. The group in which flap operation using nonresorbable nonporous hydroxyapatite (Orthomatrix) was performed was used as experimental Ⅰ. The group which flap operation using resorbable porous hydroxyapatite (Biocoral) was performed as experimental Ⅱ. The group in which flap operation using demineralized freeze-dried bone was performed was used as experimental Ⅲ. Thereafter dogs serially sacrificed at the 1,2,4 and 8 weeks and the specimens were prepared, and stained with Hematoxilin-Eosin stain for the light microscopic evaluation. The results of the this study were as follows : 1. Control group : progressive inflammatory cell infiltration till 4 weeks and epithelial undergrowth. 2. Group Ⅰ : epithelial undergrowth and new bone formed with fibrous margin around HA granule. 3. Group Ⅱ : no epithelial undergrowth and direct bone formation at the porous granule 4. Group Ⅲ : could not see epithelial undergrowth but obviously new cementum formation.

다양한 환경변이원의 분자독성학적 메커니즘 연구에 있어서 항종양 인자 p53의 중요성 고찰

정화진,류재천,서영록 한국환경독성학회 2004 환경독성보건학회지 Vol.19 No.3

The study of p53 tumor suppressor protein is one of most important subjects to an environmental toxicology as well as in cancer biology Generally, p53 has been known to Involve the cell cycle regulation and apoptosis by the activation of its target genes such as p2l and bax in a number of cellular stress responses In addition, associations of p53 with cellular proteins presumably reflect the involvement of p53 in critical cellular processes such as DNA repair The complex formation of p53 and exogenous proteins such as viral or cellular proteins has been shown in many cases to play important roles in carcinogenic processes against environmental mutagen Recently the disruption of p53 protein by oxidative stress has been also reported to have relevance to carcinogenesis These findings suggested that the maintaining of stability and functional activity of p53 protein was also important aspect to play as a tumor suppressor protein Therefore, the detection of functional status of p53 proteins might be an effective biomarker for the cancer and human diseases under the environmental toxicologic carcinogen.

Dense Kondo 계인 CeTe의 광학적 성질

정명화,김재민,권용성 성균관대학교 기초과학연구소 1995 論文集 Vol.46 No.1

Dense Kondo계인 CeTe와 정상금속인 LaTe의 크기 양질인 단결정을 개선된 Bridgeman방법으로 성장시켰다. 이 단결정을 이용하여 0.05∼8eV의 광범위한 에너지 영역에서 반사율을 측정하여, Kramers-Kronig변환을 통해 광학전도도를 얻었다. 광학전도도의 스펙트럼을 분석한 결과, CeTe와 LaTe의 경우 모두 p-d 전이에 의한 두 개의 피크가 3.6eV와 5.1eV에서 발견되었다. 이 두 피크의 형성 mechanism은 5d-band의 입방결정장에 의한 것임을 알았다. 그리고 CeTe의 경우는 LaTe에 없었던 4f-5d전이에 의한 피크가 0.4eV에서 발견되었다. 이는 XPS 스펙트럼으로부터 얻은 bare 4f-전자의 binding 에너지(약 1.5eV)에 비해 매우 작은 값이다. 이 편차는 local field를 고려한 Lorentz모델을 적용함으로서 잘 설명되었다. 또한, localization의 정도로 약 0.4의 값을 얻었다. 끝으로, 띠내전이의 해석으로부터 LaTe의 경우보다 CeTe의 경우가 전도전자의 유효질량이 무겁다는 사실을 얻었다. 이것으로부터 CeTe의 여기상태인 Γ_8와 전도전자 간의 Kondo 교환상호작용의 에너지가 매우 크다는 것을 알았다. We had grown the high quality single crystals of dense Kondo system CeTe and normal metal LaTe by using the advanced Bridgeman method. The reflectivities of the single crystals were measured in wide energy range from 0.05 to 8eV, and their optical conductivities were obtained using Kramers-Kronig transformation. By the result of their optical conductivity spectra, two peaks due to p-d transition were discovered at about 3.6 and 5.1eV, respectively. The double peaks were explained by cubic crystalline electric field. And in case of CeTe, extraordinary peak due to f-d transition, which LaTe had not, was appeared around 0.4eV. This value was well explained by the Lorentz model considering the local field. The degree of screening due to conduction electrons was evaluated to be about 0.4. The effective mass of conduction electron of CeTe was large compared with that of LaTe. From this, we could obtain the fact that in CeTe, Kondo exchange energy between conduction electron and excited Γ_8 state was very large

파일럿 채널지원 MMSE-RAKE 수신기의 성능분석

정인화,남옥우,김재형 창원대학교 정보통신연구소 2000 精報通信論文集 Vol.4 No.-

In this paper, we proposed pilot channel assisted MMSE-RAKE receiver, which use adaptive filter to provide relatively simple structure and good performance in the DS/CDMA downlink. Especially, utilizing normalized LMS(NLMS) algorithm to resolve the defect of LMS algorithms. And we explained pilot channel assisted method to estimate the multipath fading channel coefficients. With the result of performance analysis, we accepts that the adaptive MMSE-RAKE receiver much relys on the performance of channel estimator.

식도암 병기 결정에 있어서 초음파내시경의 유용성

이화영,김재준,김영호,성인경,손희정,이풍렬,고광철,백승운,이종철 大韓消化器病學會 1998 大韓消化器病學會誌 Vol.32 No.2