무가압 침투법에 의해 제조된 Al/BN 복합재료의 미세조직과 인장성질

조수연,이건배,심호섭,허성우,유황룡,권훈 대한금속재료학회(대한금속학회) 2000 대한금속·재료학회지 Vol.38 No.12

Spontaneous infiltration and strengthening behaviors were analyzed in terms of microstructures and tensile properties of Al/BN composite fabricated by pressureless infiltration technique, compared with control alloy without BN fabricated by the same method. The Mg₃N₂ formed by the reaction of Mg vapor and nitrogen gas, which coated the particles in the powder bed, is believed to induce spontaneous infiltration through a great enhancement of wetting via the following reaction, Mg₃N₂+ 2Al→2AlN + 3Mg. This was identified by the finding of AlN particle layers on the surfaces of old Al particles in the powder bed, which contacted with the infiltrating melt. In addition, unreacted Mg₃N₂ was observed outside the composite, where the Al melt directly did not come into contact. Fine AlN particles formed in-situ resulted in a significant strengthening even in the control alloy with no addition of BN. In the composite reinforced with BN, additional AlN was formed by the interfacial reaction of the BN and Al melt as well as AlN by the in-situ reaction. Consequently, both the BN particles and the additional AlN particles formed by the interfacial reaction led to a further strengthening in the composite, as compared to control alloy strengthened by the AlN particles formed in-situ.

선진복합재료 적층판의 동적 층간 파괴 인성평가

김지훈,양인영,김영남,심재기 한국산업안전학회 1998 한국안전학회지 Vol.13 No.4

In this paper, an investigation was performed on the dynamic interlaminar fracture toughness of CFRP(carbon fiber reinforcement plastics) composite laminates. Composite laminates used in this experimentation are CF/EPOXY and CF/PEEK laminated plates. In the experiments, Split Hopkinson's Bar(SHPE) test was applied to dynamic and notched flexure test. The mode II fracture toughness of each unidirectional CFRP was estimated by the analyzed deflection of the specimen and J-integral with the measured impulsive load and reactions at the supported points. As an experimental result, the vibration amplitude of CF/PEEK laminates appear more than that of CF/EPOXY laminates for the J-integral and displacement velocity at a measuring point. Also, it is thought that the dynamic. fracture toughness of two kind specimens(CFRP/EPOXY and CF/PEEK) with the in crease of displacement velocity becomes a little greater at a measuring point within the range of measurement.

원불교 사회사업의 성찰과 과제에 대한 연구 : 서기2000년과 원기 85년을 전후한 시기의 조망

심대섭 한국원불교학회 2001 圓佛敎學 Vol.6 No.-

This paper describes the self-reflection about the position and tasks of Won-Buddhist social welfare in 2000. the contents of this paper are summarized as follows. First, a benevolent spirit appears to be the most important assignment in terms of ideological self-reflection. Second, the professionalism of workers in social welfare agencies should be urgently achieved, and the status security of Won-Buddhist monks working in social welfare agencies is required. Third, the information exchanges and discussions through the association of social welfare agencies in each field should be actively performed. Fourth, social welfare practices should be carried out centering around parishes and believers in stead of the head quarter and Won-Buddhist monks. Fifth, social welfare programs making the best use of Won-Buddhist characteristics should be developed, and the support of a religious body should be established.

Plasma Secretin Concentrations in Fasting and Postprandial States of Normal Korean Subjects

심여림,조양혁,심상수,남상채,김명석,Sim, Yeo-Rim,Jo, Yang-Hyeok,Sim, Sang-Soo,Nam, Sang-Chae,Kim, Myung-Suk The Korean Physiological Society 1985 대한생리학회지 Vol.19 No.2

한국의 정상 성인 20 명에서 공복시 및 음식물 섭취후의 철장 secretin농도를 방사면역 측정법(radioimmunoassay)으로 다음과 같이 측정하였다. 20명중 12명은 단백질 음식물인 햄버거와 쌀밥을 일주일 간격으로 섭취하였다. 햄버거 섭취 추 평균 혈장 secretin농도$(12{\sim}16\;pg/ml)$는 공복시의 평균 혈장 secretin농도(10 pg/m1 이하) 보다 유의하게 증가하였으며 그 증가가 오랫동안 지속하였다. 쌀밥의 섭취 후에는 혈장 secretin농도$(9{\sim}13\;pg/ml)$가 공복시의 값보다 증가하는 경향이었으며, 단지 식후 30분의 값에서만 유의하게 증가하였다. 식후 혈장 secretin농도의 증가폭은 햄버거에서의 증가 값이 쌀밥에서의 값보다 더 컸다. 나머지 8명은 자당 용액과 생리 식염수를 마셨다. 자당 용액의 섭취후 평균 혈장 secretin농도$(10{\sim}14\;pg/ml)$는 공복시의 값보다 유의하게 증가하였으나 쌀밥의 값과 마찬가지로 일시적이었다. 그러나 생리 식염수를 섭취한 후에는 혈장 secretin농도에 이렇다할 변화가 없었다. 이상의 결과로 미루어 정상 한국 성인에서는 단백질 음식물은 물론 탄수화물 음식물의 섭취로도 혈장 secretin농도가 증가한다고 사료된다. This study was conducted to investigate fasting plasma secretin and postprandial secretin concentrations after ingestion of a protein meal or a sucrose solution in 20 healthy Korean subjects. In 12 subjects, ingestion of a protein meal, hamburger resulted in a significant and sustained increase in the mean plasma secretin concentrations, from mean fasting levels of less than 10 pg/ml to $12{\sim}16\;pg/ml$, and the mean plasma secretin concentrations, $9{\sim}13\;pg/ml$, after a rice meal increased significantly but transiently compared with mean fasting levels. The magnitude of postprandial increase in the Plasma secretin concentration after the hamburger was greater than that of the rice meal. In the remaining 8 subjects, drinking of a sucrose solution resulted also in a significant but transient increase in the mean Plasma secretin concentrations, from mean fasting levels of less than 10 pg/ml to $10{\sim}14\;pg/ml$ which were significantly greater than that after a physiological saline. Significant increase in the plasma secretin concentration was not observed during the postprandial period after the physiological saline. It is inferred from the above results that the Plasma secretin levels increase significantly after ingestions of a carbohydrate meal as well as a protein meal in the Korean race.

새로운 상호연결망 하프 버블정렬 그래프 설계 및 성질 분석

서정현,심현,이형옥,Seo, Jung-Hyun,Sim, Hyun,Lee, Hyeong Ok 한국정보통신학회 2017 한국정보통신학회논문지 Vol.21 No.7

버블정렬 그래프는 노드 대칭이며 데이터 정렬 알고리즘에 활용 할 수 있다. 본 연구에서는 버블정렬 그래프의 망 비용을 개선한 하프 버블정렬 그래프를 제안하고 분석한다. 하프 버블정렬 그래프 $HB_n$의 노드수는 n!이고 분지수는 ${\lfloor}n/2{\rfloor}+1$이다. 하프 버블정렬 그래프의 분지수는 버블정렬 그래프의 분지수의 $${\sim_=}0.5$$배 이고, 지름은 $${\sim_=}0.9$$배 이다. 버블정렬 그래프의 망 비용은 $${\sim_=}0.5n^3$$이고, 하프 버블정렬 그래프의 망 비용은 $${\sim_=}0.2n^3$$이다. 하프 버블정렬 그래프는 버블정렬 그래프의 서브 그래프임을 증명하였다. 추가로 라우팅 알고리즘을 제안하였고 지름을 분석하였다. 마지막으로 버블정렬 그래프와 망 비용을 비교 하였다. The Bubble sort graph is node symmetric, and can be used in the data sorting algorithm. In this research we propose and analyze that Half Bubble sort graph that improved the network cost of Bubble sort graph. The Half Bubble sort graph's number of node is n!, and its degree is ${\lfloor}n/2{\rfloor}+1$. The Half Bubble sort graph's degree is $${\sim_=}0.5$$ times of the Bubble sort, and diameter is $${\sim_=}0.9$$ times of the Bubble sort. The network cost of the Bubble sort graph is $${\sim_=}0.5n^3$$, and the network cost of the half Bubble sort graph is $${\sim_=}0.2n^3$$. We have proved that half bubble sort graph is a sub graph of the bubble sort graph. In addition, we proposed a routing algorithm and analyzed the diameter. Finally, network cost is compared with the bubble sort graph.

수확후 채소류에 발생하는 진균독소의 탐색과 방제 (II) 이병된 양념 채소류(양파, 마늘, 고추)에서 주요 진균독소 검출

정일민,주호종,심성철,백수봉,유승헌,Chung, Ill-Min,Ju, Ho-Jong,Sim, Sung-Chur,Paik, Su-Bong,Yu, Seung-Hun 한국분석과학회 1998 분석과학 Vol.11 No.3

수확후 Alternaria, Penicillium 및 Fusarium에 이병된 고추, 양파, 마늘을 HPLC로 주요독소들을 검정한 결과 고추에서 Alternaria 독소의 AOH(alternariol)는 소량~$400{\mu}g/g$, ALT(alternuene)는 소량~$103{\mu}g/g$, TeA(tenuagonic acid)는 $249{\sim}342{\mu}g/g$ 및 AME(alternariol monomethyl ether)는 $206{\sim}294{\mu}g/g$이 검출되었고 양파, 마늘에서 Penicillium 독소의 citrinin이 $2.8{\sim}18.4{\mu}g/g$, penicillin-G는 $0{\sim}439.0{\mu}g/g$, penicillic acid는 $0{\sim}10.2{\mu}g/g$ 및 patulin은 $0{\sim}7.0{\mu}g/g$ 검출되었다. 그리고 양파, 마늘에서 Fusarium 독소로는 fusaric acid가 $0{\sim}553.6{\mu}g/g$ 검출되었을 뿐 deoxynivalenol과 nivalenol은 검출되지 않았다. The major mycotoxins were detected from peppers, onions and garlics infected postharvest pathogens, Alternaria, Penicillium and Fusarium. Analyses of the major mycotoxins were conducted using HPLC. Detected Alternaria mycotoxins per gram of infected postharvest peppers were alternariol (AOH) with amount ranged from small quantity to $440{\mu}g/g$, altenuene (ALT) with amount ranged from small quantity to $103{\mu}g/g$, tenuagonic acid (TeA) with amount ranged from 249 to $342{\mu}g/g$ and alternariol monomethyl ether (AME) with amount ranged from 206 to $294{\mu}g/g$. Penicillium toxins per gram of infected postharvest onions and garlics were citrinin with amount ranged from 2.8 to $18.4{\mu}g/g$, penicillun-G with amount ranged from no detection to $439.0{\mu}g/g$, penicillic acid with amount ranged from no detection to small quantity and patulin with amount ranged from no detection to small quantity. Fusarium toxins per gram of infected postharvest onions and garlics were fusaric acid with amount ranged from no detection to $553.6{\mu}g/g$. However, deoxyrivalenol and nivalenol were not detected from onins and garlics infected by Fusarium.

Does Age Influence the Poor Prognosis after Aneurysmal SAH Surgery in Elderly Patients?

Sim, Jong-Eun,Kim, Hyung-Dong,Song, Young-Jin,Noh, Seung-Jin The Korean Neurosurgical Society 2006 Journal of Korean neurosurgical society Vol.40 No.5

Objective : The incidence of aneurysmal subarachnoid hemorrhage has been increasing. At the same time, surgical results for elderly patients are unsatisfactory and no guidelines of treatment are available. We carried out a study comparing variable factors and surgical results between young and old age groups to find ways to improve prognosis. Methods : A retrospective study was carried out on 754 patients who were operated on between 1990 and 2004 by the same surgeon in our hospital. The patients were divided into seven groups according to age : 93 patients below 40 years of age [Group I], 419 patients aged $40{\sim}59$ [Group II], 115 patients aged $60{\sim}64$ [Group III], 82 patients aged $65{\sim}69$ [Group IV], 28 patients aged $70{\sim}74$ [Group V], 12 patients aged $75{\sim}79$ [Group VI] and 5 patients over the age of 80 [Group VII]. We then checked their medical history, Fisher's grade, Hunt-Hess grade, postoperative complications, and Glasgow Outcome Scale. Results : Age was not a statistically significant factor among patients below 70 years of age [P $value{\ge}0.05$]. But for those aged 70 and older, the age factor had a statistical value [P $value{\le}0.001$]. In addition, there was a close correlation between Hunt-Hess grade IV and V patients, and those with vasospasm, and hydrocephalus after surgery, with poor prognosis in elderly patients as well as young patients [P $value{\le}0.001$]. Conclusion : Advanced age [under the age of 70] dose not precluded adequate surgical treatment in patient with AN SAH, and we should be also alert to preventable causes of delayed neurological deterioration for improving the outcome in all elderly groups.

2상 유동 내 관군에서의 압력 손실

심우건(Woo Gun Sim),닥단(Dagdan Banzragch) 대한기계학회 2016 大韓機械學會論文集B Vol.40 No.3

수평 관군에 대하여 수직이고 상향으로 흐르는 2상 유동에 의한 감쇠비를 예측하기 위한 해석모델이 Sim에 의하여 개발되었다. 이 모델에서 평가된 2상 유동의 기공률, 압력손실 등의 유동변수는 기존의 실험식을 사용하여 계산하였다. 그러나 관군의 경우에 사용하기에는 약간의 개선이 요구된다. 따라서 관군 내에 흐르는 2상 유동의 유동 변수에 대한 더 많은 정보를 획득하기 위하여 실험적으로 연구할 필요가 있다. 실험은 공기 - 물의 2상 유동이 흐르는 정사각형 배열 관군에서의 압력계수와 2상 유동 마찰승수를 계산하기 위하여 수행되었다. 피치 직경 비는 1.35이었고, 실린더의 직경은 18 mm이다. 압력센서와 신호처리 장치를 이용하여 관군에서의 압력차를 측정하였다. 2상 유동 마찰승수와 오일러수를 계산하기 위하여 관군에 적용되는 비균질 유동의 기공률은 Feenstra 등의 실험식을 사용하여 계산하였다. 균질과 비균질 2상 유동의 마찰승수와 오일러의 수를 실험적으로 구하고 Sim의 어림적 모델에 근거한 이론적 해석 결과와 비교・분석하였다. An analytical model was developed by Sim to estimate the two-phase damping ratio for upward two-phase flow perpendicular to horizontal tube bundles. The parameters of two-phase flow, such as void fraction and pressure loss evaluated in the model, were calculated based on existing experimental formulations. However, it is necessary to implement a few improvements in the formulations for the case of tube bundles. For the purpose of the improved formulation, we need more information about the two-phase parameters, which can be found through experimental test. An experiment is performed with a typical normal square array of cylinders subjected to the two-phase flow of air-water in the tube bundles, to calculate the two-phase Euler number and the two-phase friction multiplier. The pitch-to-diameter ratio is 1.35 and the diameter of cylinder is 18mm. Pressure loss along the flow direction in the tube bundles is measured with a pressure transducer and data acquisition system to calculate the two-phase Euler number and the two-phase friction multiplier. The void fraction model by Feenstra et al. is used to estimate the void fraction of the two-phase flow in tube bundles. The experimental results of the two phase friction multiplier and two-phase Euler number for homogeneous and non-homogeneous two-phase flows are compared and evaluated against the analytical results given by Sim"s model.

말기 암환자의 임종 전 48시간 동안의 임상증상

심윤수,김도연,남은미,이순남,Sim, Yun-Su,Kim, Do-Yeun,Nam, Eun-Mi,Lee, Soon-Nam 한국호스피스완화의료학회 2007 한국호스피스.완화의료학회지 Vol.10 No.4

목적: 말기 암환자의 여명을 예측하는 것은 환자와 가족들에게 '평안한 임종'을 맞기 위한 준비를 할 수 있도록 하고, 의료진에게는 적극적 증상완화와 전인간적 돌봄을 가능하게 할 수 있다. 이에 본 연구는 말기 암환자에서 임종 전 48시간 동안의 임상증상을 파악하고 임종을 예측하는 임상증상을 확인하여 환자 가족 및 의료진에게 이 시기에 나타나는 변화들을 이해하여 준비된 평안한 임종을 맞는데 도움이 되고자 한다. 방법: 2003년 7월부터 2006년 3월까지 한 대학병원에 입원하여 사망한 말기 암환자 89명을 대상으로 하여 임종 전 48시간 동안의 임상증상을 조사하였고 입원 시, 임종 48시간-24시간전, 임종 24시간전$\sim$임종시까지 시간대별 증상의 빈도 변화를 분석하였다. 결과: 전체 대상 환자의 중앙 연령은 62세(범위, $16{\sim}97$세)였다. 임종 48시간전 임상증상의 빈도는 의식혼탁(57%)이 가장 흔하였으며 이외 통증(30%), 발열(22%), 호흡곤란(19%)의 순이었다. 원발암에 따른 임종 48시간전 임상증상도 유사한 빈도를 보였으나 담도계암환자에서 발열의 빈도가 다른 암종에 비해 유의하게 높았다(P=0.012). 임종이 임박할수록 입원 시에 호소하던 전신 쇠약감과 식욕부진은 감소한 반면 의식혼탁은 유의하게 증가하였다(P<0.001). 결론: 말기 암환자에서 의식혼탁은 임종이 임박했음을 나타내는 가장 중요한 임상 지표로 생각된다. Purpose: Individual cancer patients often experience many symptoms that impair their quality of life at the end of life. Identifying symptoms at the terminal stage of cancer patients and possible imminent death prediction by using that assessment can assist physicians and patients in preparing the 'peaceful death'. This study examines symptom experience during the last 48 hours of life of terminal cancer patients, and determines whether symptom experience change with proximal to death. Methods: The medical records of 89 patients who died with terminal cancer at a hospital between July 1, 2003 and March 31, 2006 were reviewed. Symptom prevalence at the last 48 hours was analyzed along with the change of symptom experience at the admission, $48{\sim}24$ hours, and $24{\sim}0$ hours before death. Results: Median age of all patients was 62 years old (range $16{\sim}97$). During the last 48 hours, symptom prevalence was described as follows; unclear consciousness (57%), pain (30%), fever (22%), and dyspnea (19%). According to the primary site, unclear consciousness was notified the most frequent symptom, but fever was relatively high prevalence in patients of biliary origin cancer rather than other site cancer (P=0.012). As death was Impending, the prevalence of poor appetite and general weakness were decreased, while that of unclear consciousness was increased, which were all statistically significant (P < 0.05). Conclusion: The presence of unclear consciousness could be regarded as the symptom indicator as imminent death of terminal canter patients.

VERTICAL PROPERTIES OF THE GLOBAL HAZE ON TITAN DEDUCED FROM METHANE BAND SPECTROSCOPY BETWEEN 7100 AND 9200Å

Sim, Chae-Kyung,Kim, Sang-Joon,Kim, Joo-Hyeon,Seo, Haing-Ja,Jung, Ae-Ran,Kim, Ji-Hyun The Korean Astronomical Society 2008 Journal of The Korean Astronomical Society Vol.41 No.3

We have investigated the optical properties of the global haze on Titan from spectra recorded between 7100 and $9200{\AA}$, where $CH_4$ absorption bands of various intensities occur. The Titan spectra were obtained on Feb. 23, 2005 (UT), near the times of the Cassini T3 flyby and Huygens probe, using an optical echelle spectrograph (BOES) on the 1.8-m telescope at Bohyunsan Observatory in Korea. In order to derive the optical properties of the haze as a function of altitude, we developed an inversion radiative-transfer program using an atmospheric model of Titan and laboratory $CH_4$ absorption coefficients available from the literature. The derived extinction coefficients of the haze increase toward the surface, and the coefficients at shorter wavelengths are greater than those at longer wavelengths for the 30 - 120 km altitude range, indicating that the Titanian haze becomes optically thin toward the longer wavelength range. Total optical depths of the haze are estimated to be 1.4 and 1.2 for the 7270 - $7360{\AA}$ and 8940 - $9150{\AA}$ ranges, respectively. Based on the Huygens/DISR data set, Tomasko et al. (2005) reported total optical depths of 2.5 - 3.5 at $8290{\AA}$, depending on the assumed fractal aggregate particle model. The total optical depths based on our results are smaller than those of Tomasko et al., but they partially overlap with their results if we consider a large uncertainty from possible variations of the $CH_4$ mixing ratio over Titan's disk. We also derived the single scattering albedo of the haze particles as a function of altitude: it is less than 0.5 at altitudes higher than ${\sim}150\;km$, and approaches 1.0 toward the surface. This behavior suggests that, at altitudes above ${\sim}150\;km$, the average particle radius is smaller than the wavelengths, whereas near the surface, it becomes comparable or greater.