질소분압에 따른 TaNx coating층의 미세조직 연구

김선화,최용락 순천향대학교 부설 산업기술연구소 1998 순천향 산업기술연구소논문집 Vol.3 No.3

TaNx film were fabricated for this research by the reactive magnetron sputtering process. In order to improve TCR, it was investigated the transformation of coated TaNx film. The variables were the N₂/Ar fraction and the thermal heat-treatment. The electrical resistance and the TCR of specimen were measured. It was observed the microstructure change under thermal heat-treatment by XRD experiment. Also the morphology of TaNx film was observed by SEM. As a result, TCR was stabilized when N₂/Ar fraction were 0.166 to 0.25. The phases of as-coated TaNx film were Ta, TaN, β-Ta and amorphous. The new phases, Ta₄N and Ta₃N?? were formed after thermal heat-treatment. As the ratio of nitrogen gas was increased, the morphology of the layer was changed to a discontinuous island particle. These results were consistent with results of electrical resistance change.

칠절봉 신갈나무(Quercus mongolica)림의 군락구조와 토양환경

이호준,배병호,전영문,정흥락,홍문표,김용옥,길지현 建國大學校基礎科學硏究所 1998 理學論集 Vol.23 No.-

칠절봉 신갈나무림의 군락구조와 토양환경과의 관계를 파악하기 위해 식물사회학적 조사와 토양 환경을 분석하였다. 조사지역의 신갈나무림은 신갈나무군락, 철쭉꽃하위군, 큰개별꽃하위군으로 구분되었으며, 철쭉꽃하위군과 큰개별꽃하위군에서의 방형구당 평균출현종수는 각각 30종(24∼46종), 43종(31∼52종) 이었다. 피복지수치에 의한 계층별 우점순위는 교목층에서 신갈나무(6750.0), 아교목층에서 당단풍(2364.0) 관목층에서 철쭉꽃(988.5), 초본층에서 쌀새(1040.5)가 가장 높게 나타났다. 신갈 나무림의 DBH 분포는 2∼10㎝ 범위의 소경목이 전체의 29.7%를 차지하였으며 전체적으로 정규분포를 나타내어 교란 후 재생과정에 있는 것으로 조사되었다. 또한 후계목의 발달로 인한 극상상태로의 천이가 가능할 것으로 조사되었다. 전반적인 토양환경은 두 하위군 간에 뚜렷한 차이가 없었으며, 큰개별꽃하위군이 철쭉꽃하위군에 비하여 다소 양호한 것으로 조사되었다. 환경구배분석에서 까치박달, 물푸레나무, 함박꽃나무 등은 습한 곳에 분포하고 철쭉꽃, 전나무, 국수나무 등은 건조한 곳에 분포하는 것으로 나타났다. A relationship between the community structure composition and soil environmental factors of the Quercus mongolica forest on Mt. Chiljelbong was investigated from June 1996 to August 1997. The Q. mongolica community was classified into two subcommunity of Rhododendron schlippenbachii and Pseudostellaria palibiniana. The 30(24-46) species per quadrat were appeared in R. schlippenbachii subcommunity and 43(31-52)species in P. palibiniana subcommunity. The dominant sequences on each stratum determined by the coverage index showed that Q. mongolica was the most dominant in tree-1 layer with 6750.0, Acer pseudo-sieboldianum in tree-2 layer with 2364.0, R. schlippenbachii in shrub layer with 988.5, and Melica onoei in herb layer with 1040.5 value. The value of diameter breast height(DBH) showed a normal distribution displaying a highest value in the range of 2∼10㎝(29.7%) in Q. mongolica forest and it was investigated being at restoration phase after disturbance. It also was investigated that the succession to climax state would be possible due to growth of successive tree. Overall, which the soil conditions make little difference between two subcommunities, P. palibiniana subcommunity was favorable than those of R. schlippenbachii subcommunity. It was shown that in an environmental gradient analysis, Carpinus cordata, Fraxinus rhynchophylla, and Magnolia sieboldii were distributed in a mesic area, but R. schlippenbachii, Abies holophylla, and Stepanandra incisa in a xeric area.

PSR-Based Microstructural Modeling for Turbulent Combustion Processes and Pollutant Formation in Double Swirler Combustors

Kim, Yong-Mo,Kim, Seong-Ku,Kang, Sung-Mo,Sohn, Jeong-Lak The Korean Society of Mechanical Engineers 2001 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.15 No.1

The present study numerically investigates the fuel-air mixing characteristics, flame structure, and pollutant emission inside a double-swirler combustor. A PSR(Perfectly Stirred Reactor) based microstructural model is employed to account for the effects of finite rate chemistry on the flame structure and NO formation. The turbulent combustion model is extended to nonadiabatic flame condition with radiation by introducing an enthalpy variable, and the radiative heat loss is calculated by a local, geometry-independent model. The effects of turbulent fluctuation are taken into account by the joint assumed PDFs. Numerical model is based on the non-orthogonal body-fitted coordinate system and the pressure/velocity coupling is handled by PISO algorithm in context with the finite volume formulation. The present PSR-based turbulent combustion model has been applied to analyze the highly intense turbulent nonpremixed flame field in the double swirler combustor. The detailed discussions were made for the flow structure, combustion effects on flow structure, flame structure, and emission characteristics in the highly intense turbulent swirling flame of the double swirler burner.

Advances, Limitations, and Future Applications of Aerospace and Geospatial Technologies for Apple IPM

Yong-Lak Park,Jum Rae Cho,Kyung-Hee Choi,Hyun Ran Kim,Ji Won Kim,Se Jin Kim,Dong-Hyuk Lee,Chang-Gyu Park,Young Sik Cho 한국응용곤충학회 2021 한국응용곤충학회지 Vol.60 No.1

항공 및 지리 공간 기술은 연구자 및 농업관련 실무자들이 더욱더 쉽게 접근할 수 있게 되었으며, 이러한 기술은 농업과 임업에 있어 현재 병해충 관리의 변화에 중추적인 역할을 할 수 있다. 지난 20년 동안 위성, 유무인항공기, 스펙트럼 센서들, 정보 시스템 및 자동화 현장 장비들의 기술들은 병해충을 감지하고, 특정 지점에 대한 병해충을 방제하는데 사용되어져 왔다. 빅 데이터 기반한 인공 지능과 함께 항공 및 지리 정보 기술의 가용 함에도 불구하고 이러한 기술을 사과 IPM에 적용하는 것은 아직 실현되지 않았다. 본 논문은 사과연구소에서 수행한 사례 연구를 통해 사과 IPM 개선에 활용할 수 있는 항공 및 지리 정보기술의 발전과 한계에 대해 논하고자 한다. Aerospace and geospatial technologies have become more accessible by researchers and agricultural practitioners, and these technologies can play a pivotal role in transforming current pest management practices in agriculture and forestry. During the past 20 years, technologies including satellites, manned and unmanned aircraft, spectral sensors, information systems, and autonomous field equipment, have been used to detect pests and apply control measures site-specifically. Despite the availability of aerospace and geospatial technologies, along with big-data-driven artificial intelligence, applications of such technologies to apple IPM have not been realized yet. Using a case study conducted at the Korea Apple Research Institute, this article discusses the advances and limitations of current aerospace and geospatial technologies that can be used for improving apple IPM.

Molecular Cloning and Sequence Analysis of a New Sialyltransferase Gene Family

김경숙,김경운,정정한,최용락,조용수,김도훈,김철호,이영춘 한국생명과학회 1998 한국생명과학회 학술발표회 Vol.20 No.-

We have cloned a new member (STRl) of the sialyltransferase gene family from mouse brain cDNA libraries using sequence information obtained from the conserved amino acid sequence of the previously cloned sialyltransferases. The cDNA sequence included an open reading frame coding for 320 amino acids, and the deduced amino acid sequence showed the highest homology (43% identity) with that of NeuAc α 2,3Galβ1,3GalNAc α2,6-sialyltransferase (ST6GalNAc III) among those of so far cloned mouse sialyltransferases. The primary structure of STRl indicated a type II transmembrane topology, as has been found in all glycosyltransferases cloned to date, consisting of an NH₂-terminal cytoplasmic domain (6 residues), a hydrophobic transmembrane domain (32 residues), and a COOH-terminal active domain (264 residues). The predicted amino acid sequence of STRl contained the highly conserved sialylmotifs L and S, as has been identified in the other cloned sialyltransferases. The expression of mRNA was the highest in colon, followed by brain, and low level being found in thymus, lung, heart, spleen, while signals were not detectable for salivery grand, liver and kidney.

척추수술시 Esmolol 을 이용한 유도저혈압

김종수,이진호,김지애,고홍,김용락,도상환,오용석 대한마취과학회 1998 Korean Journal of Anesthesiology Vol.35 No.5

Background: Esmolol as a drug for induced hypotension can, not only avoid many drawbacks of nitroprusside, but reduce the amount of intraoperative bleeding and make better operative field. This study was performed to evalute cardiovascular changes during esmolol-induced controlled hypotension. Methods: Induced hypotension using esmolol was applied to 18 adult patients receiving spinal surgery under the diagnosis of spinal stenosis or scoliosis. After prehydraion of 2,000 ml of crystalloid solution, 0.5 mg/kg esmolol was used as loading dose once, twice or three times until mean blood pressure (MBP) fell below 70 mmHg, followed by continuous infusion (50∼300 g/kg/min) of esmolol. MBP and heart rate (HR) were measured before, 5, 10, 15, 30, 60 and 90 min after esmolol administration, and 5, 10 and 15 minutes after discontinuation of esmolol. In 8 patients, cardiac output (CO) and mixed venous oxygen tension and saturation were measured before, during and after esmolol use. Results: MBP was decreased from 91 12 mmHg to 67 7 mmHg after 15 min (P<0.05). HR(BPM) was decreased from 76 17 to about 60 after 15 min (P<0.05). CO was decreased about 30% during induced hypotension but recoverd to initial level 15 min after esmolol discontinuation. While oxygen transport was reduced significantly during induced hypotension (P<0.05), oxygen consumption was maintained all the time. Conclusion: With the use of esmolol, stable hypotension could be achieved. Although oxygen transport decreased possibly due to reduction of CO, but oxygen consumption was maintained. (Korean J Anesthesiol 1998; 35: 921∼925)

분산네트워크 환경에서의 Logging 기반 BTM 설계 및 구현

김용옥(Yong-Ok Kim),최용락(Yong-Lak Choi),성기범(Ki-Bum Sung),이남용(Nam-yong Lee),김종배(Jong-Bae Kim) 한국통신학회 2013 韓國通信學會論文誌 Vol.38 No.12(네트워크)

아동 수면 양상과 관련된 지역별 사회, 환경적 요인들

최용락(Yong-Lak Choi),서완석(Wan-Seok Seo),성형모(Hyung-Mo Sung),구본훈(Bon-Hoon Koo),김경근(Kyung-Keun Kim),김소연(So-Yeun Kim),최소정(So-Jeong Choi),이종훈(Jong-Hun Lee) 대한생물치료정신의학회 2009 생물치료정신의학 Vol.15 No.1

Objectives:This study was conducted to investigate various social and environmental factors related to children’s sleep and to know how these factors may affect sleep duration and patterns. Methods:Total 2,958 students of three elementary school in Daegu, Korea were enrolled in this study. We investigated various factors related to children’s sleep using Sleep questionnaires for Korean Children(SKC) for two days. The factors that we investigated were classified into sleep-related factors, daily life factors, environmental factors. We also evaluated correlations between these factors and children’s sleep duration. Results:When identifying various factors related to children’s sleep in three elementary school groups, group A showed significantly later bedtime(F=103.683, p<.001), longer sleep latency(F=6.30, p<.05), shorter total sleep duration(F=5.93, p<.05), and shorter nap duration(F=141.94, p<.001) compared to other group B and C. Also, group A showed significantly earlier time of returning home(F=71.073, p<.001), shorter amount of TV viewing (F=108.45, p<.001), earlier time of stopping TV viewing(F=24.01, p<.001), shorter amount of computer use(F=67.10, p<.001), earlier time of attending school(F=5.40, p<.05), longer hours in private institute(F=15.57, p<.001), smaller number of family(F=11.00, p<.001), longer father’s years of education(F=311.82, p<.001), and longer mother’s years of education(F=334.87, p<.001) compared to other two groups. Conclusion:Group A was associated with late bedtime, long sleep latency, short total sleep duration despite relatively short nap duration, short amount of TV viewing, short amount of computer use, early time of stopping TV viewing, small number of family, long mother’s years of education. This result suggests that total amount of hours in private institute and parents’ academic demands might be a contributing factor for children’s sleep duration.

상세 불명의 현성 장출혈에 대한 임상적 고찰

김종표 ( Kim Jong Pyo ),한동수 ( Han Dong Soo ),이항락 ( Lee Hang Lak ),김진배 ( Kim Jin Bae ),박준용 ( Park Joon Yong ),은창수 ( Eun Chang Soo ),이오영 ( Lee Oh Yong ),손주현 ( Sohn Joo Hyun ),최호순 ( Choi Ho Soon ),함준수 ( Hah 대한소화기학회 2003 대한소화기학회지 Vol.42 No.1

Background/Aims: Obscure gastrointestinal bleeding (OGIB) is defined as recurrent acute or chronic bleeding for which no sources have been identified by routine endoscopic and contrast studies. The patients with OGIB are frequently difficult to manage and often undergo extensive investigation and even laparatomy without diagnosis. The aim of this study was to review our overall experiences of the investigation and treatment of OGIB. Methods: We reviewed, retrospectively, medical records of 41 cases with OGIB from June 1996 to July 2002. Results: Of the 41 patients with OGIB, there were 21 men and 20 women and their mean age was 47.8 years (range, 18 to 81 years). Diagnosis was possible in 13 patients (31.7%) and no specific causes were identified in the remaining 28 patients (68.3%). The principal etiologies were gastrointestinal stromal tumor of the small bowel in 3 cases, duodenal diverticulum in 2 cases. Other causes are as follows: adenocarcinoma of the duodenal 3rd portion, duodenal varix at the 4th portion, splenic artery pseudoaneurysm, Crohn’s disease, jejunal ulcer, ileal ulcer, ileal angiodysplasia, and anastomosis site bleeding after hemicolectomy. Conclusions: We conclude that further and logical diagnostic investigations such as small bowel enteroscopy and wireless capsule endoscopy will promise better results. (Korean J Gastroenterol 2003;42:27-34)

최적 제어 이론을 이용한 서어보 메카니즘 PID 제어기 설계

최중락(Joong-Lak Choi),김재환(Jae-Whan Kim),정구락(Ku-Lak Jung),김영수(Yong-Su Kim) 제어로봇시스템학회 1986 제어로봇시스템학회 국내학술대회 논문집 Vol.1 No.10