活性炭 吸着分離에 미치는 溶液 pH의 影響

崔乘載,李秉學,金鍾聲 단국대학교 1981 論文集 Vol.15 No.-

By this experiment, we have the following result. In the activated carbon equilibrium adsorption of dilute aqueous solution of phenol, the adsorption quantity became the largest when solution pH was adjusted as -4<pH-pKa<-1 to each pKa. That is, as pH-pKa<-4, due to the acid adsorptive effect, the equilibrium adsorption quantity decreased, and for pH-pKa>-1, due to adsorption ionization, the equilibrium adsorption decreased. As for the fixed bed adsorption and initial adsorptive rate, in case of acid zone, due to acid adsorption, the adsorptive rate was slow, otherwise, in basic zone, by ionization, the adsorption decreased to commence breakthrough rapidly to have slow the adsorptive rate. As a result, there appeared a strong aqueous solution pH effect influenced on the adsorptive rate.

세탄가를 向土시킨 LPG 戰料의 壓縮着火 디젤 엔진의 性能및 排出가스 特性에 關한 硏究

崔源歸,柳鍾植,車京玉 明知大學校 産業技術硏究所 2009 産業技術硏究所論文集 Vol.28 No.-

In this study, a feasibility test of liquefied petroleum gas (LPG) direct injection (DI) compression ignition engine has been carried out to study the effectiveness of cetane enhancing additive; Di-tertiary-butyl peroxide(DTBP) Performance and emissions characteristics of a diesel engine fuelled with LPG and DTBP blended fuel were examined Results showed that stable diesel engine operation over a wide range of the engine loads was possible. Estimated cetane number of the LPG with a 15 wt% DTBP was more than 55 suggesting the possibility of utilizing LPG as a DME(dimethyl ether). Exhaust emissions measurements showed that hydrocarbon was decreased with the blended fuel at enhancing cetane number. Furthermore, the combustion stability of LPG with a cetane number improver was comparable to DME fuel. Considering the results of engine performance and exhaust emissions, LPG blended fuel of enhancing cetane number could be used as an alternative fuel for diesel.

LPG/DME 混合熱料를 使用하는 壓縮着火엔진의 性能및 排氣特性에 관한 硏究

崔源歸,柳鍾植,車京玉 明知大學校 産業技術硏究所 2009 産業技術硏究所論文集 Vol.28 No.-

In this study, DME-blended LPG fuel was experimentally investigated in CI(compression ignition) engine. In particular, performance, emissions characteristics (including hydrocarbon, CO, and NOx emissions), and combustion stability of engine fuelled with DME-blended LPG fuel were examined. LPG fuel was blended to DME fuel by LPG 0-40wt%, Results showed that stable engine operation was possible for a wide range of engine loads up to 30% of LPG by mass in a CI engine. Considering the results of the engine power out put and exhaust emissions, blended fuel up to 30% of LPG by mass can be used as an alternative to diesel in a CI engine. DME blended LPG fuel is expected to have potential for enlarging the DME market.

醫學映像檢査에 대한 臨床的 統計의 分析

최종학,이창엽 高麗大學校 倂設 保健大學 保健科學硏究所 1998 保健科學論集 Vol.24 No.1

This study was to analyze statistical data to find the distribution of the latest medical imaging technology in the field of Computed Tomography(CT), Ultrasonography and Magnetic Resonance Imaging(MRI). The data were obtained from diagnostic radiology, Korea University Hospital in the recent 5 years(l993-1997). The results were as follows. 1. The total number of patients examined using CT were 44,990. According to the order of examination items, brain examination had the most patients among various diagnostic areas followed by abdomen(12,101), chest(3,176), pelvis(2,207), neck(2,118) and spine(l,848) in sequence. 2. There were 62,090 patients examined by ultrasonography. According to the order of examination items, upper abdomen region had the most patients(50,630) followed by lower abdomen region(2,925), biopsy and aspiration(l,971), duplex(l,431), breast(972) and sonoguided P.EJ.(950) in sequence. 3. The total number of patients examined using MRI were 16,827. According to the order of examination items, brain showed the highest cases(8,270 patients) followed by lumbar vertebra(2,631), chest · mediastinum · lung(l,124), cervical vertebra(l,221), thoracic vertera(752) and knee joint(567). 4. The monthly distribution of patients for medical imaging ware 2,296 on the average. The number of patients did not show significant change according to mouths and four seasons. 5. In terms of time shift for examination, the most patients were examined during 9 to 10 AM(33.0%), followed by 11-12 AM(20.1%), 1-2 PM(11.3%), 3-4 PM(11.2%), 7-8 AM(7.7%) and 5-6 PM(6.1%) in sequence. 6. The age distribution of patients in medical imaging, 55-59 years had a more than majority(15.5%) followed by 40-44 years(10.6%), 50-54 years(10.3%), over 70 years(9.0%), 45-49 years(8.5%) and 60-64 years(8.2%) in sequence. 7. For sex distribution, male patients showed a higher percentage(56.4%) for examination than female patients(43.6%). 8. In relation to referral departments for 3 fields, emergency medicine made the most referrals for CT followed by gastrointestinal internal medicine, otorhinolaryngology, general surgery, neurosurgery, hematooncology and neurology in sequnce. Additionaly, ultrasonography had a different distribution compared with CT, shoring the most referrals from gastrointestinal internal medicine, general surgery, emergency medicine, nephrology, family medicine, pediatrics and pulmonology. For MRI, neurosurgery had the most cases of referrals followed by neurology, orthopedic surgery, rehabilitation medicine, psychiatry, otorhinolaryngology and gastrointestinal internal medicine. 9. CT showed 67.5% of contrast medium usage-rate followed by 60.4% of it in MRI. In contrast, ultrasonogrphy did not use any contrast medium. 10. For films used, 4 films(33.3%) were used most in CT, 2 films(28.6%), 3 films(16.2%) and 1 film(8.5%). For ultiasonography, 1 film(58.7%), 2 films(40.6%) and for MRI, 7 films(37.1%), 5 films(20.1%), 4 films(12.2%), 6 films(8.9%) in sequence.

韓國의 人口移動에 관한 硏究

崔鍾碩,林裁鶴 충남대학교 자연과학연구소 1987 忠南科學硏究誌 Vol.14 No.2

Several projects for the national economic development plannings since 1960's have brought a tremendous change in the whole nation socially, economically as well as geo-demographically Since 1970's advanced industrialization with high technology, achieving a big economic development, has accelerated urbanization, which on the other hand resulted in a serious lack of labor in the rural area. This serious unbalanced distribution of the population between the urban and the rural area has caused not only political and societal gap between the two areas but also the inefficient use of the land. We, with a very dense population, think that the above problems could be solved partly through strong policies of restraint on population growth and on population migration into the urban area. This study has been done as a base for the policies in the followings. 1. In order to observe the phenomenon of population migration, we analyze time series intra and inter-migration and total migration. 2. To investigate the cyclic phenomenon, seasanal variation analysis on one-year base is considered additionally. 3. We investigate, in macro sense, redistribution of population by showing the migration trend based on the center of population gravity and that of geographic gravity. 4. We specially focus on the population moving problem toward the metropolitan area. 5. We end up this study with the possible suggestions for the policy making on the population problem after discussing some predictions of migration trend.

H형 패치 안테나 설계

최석호,김학선,박종권 한밭대학교 정보통신전문대학원 2003 정보통신전문대학원 논문집 Vol.1 No.1

이 논문은 H형 패치 안테나가 무선통신에 적합하다는 것을 보여준다. H형 패치 안테나는 기존의 사각형 패치 안테나처럼 작은 크기, 적은 제작비용, 고조파 성분에서의 비 공진과 같은 몇 가지 장점을 가진다. H형 패치 안테나의 기본적인 이론과 설계과정 및 시뮬레이션 결과를 소개하였다. In this paper, H-shaped patch antenna suitable for wireless communication is presented. This antenna has several advantages compared to conventional rectangular microstrip patch antennas such as small size, low cost fabrication and absence of harmonic resonance. The fundamental principle, simulated result and design procedure are presented.

LPG/바이오디젤 混合縣料를 使用하는 壓縮着火 機關에서 바이오디젤이 엔진 性能 및 排氣特性 에 미치는 影響

崔源鶴,柳鍾植,車京玉 明知大學校 産業技術硏究所 2009 産業技術硏究所論文集 Vol.28 No.-

In this study, a compression ignition engine operated with LPG and Bio-diesel blended fuel was studied experimentally. The effect of Bio-diesel on performance and emissions of a CI engine fuelled by LPG/Bio-diesel fuel were examined‘ Bio-diesel fuel was blended to LPG fuel by Bio-diesel 20-60wt%. Results showed that stable engine operation was possible for a wide range of engine loads up to 30% of LPG by mass in a CI engine. Considering the results of the engine power out put and exhaust emissions, blended fuel up to 30% of LPG by mass can be used as an altemative to diesel in a CI engine. Bio-diesel blended LPG fuel is expected to have potential for enlarging the Bio-diesel market.

CPW급전을 이용한 UWB 안테나 설계

최석호,이성훈,김학선,박종권 한밭대학교 정보통신전문대학원 2004 정보통신전문대학원 논문집 Vol.2 No.1

본 논문은 CPW급전 구조와 CST사의 Microwave Studio 사용하여 UWB 안테나를 설계하였다. 시물레이션 결과 제안된 안테나의 대역폭은 3.O5-13GHz를 가지고 방사패턴은 무지향성의 형태를 갖는 것을 보였다. In this paper, we have designed a UWB antenna using CPW feed line and used the Microwave Studio of CST to simulate the UWB antenna. Simulated results show that antenna bandwidth is 3.05-13GHz and radiation pattern is omni-directional.

陸上競技 記錄의 豫測과 性差

崔鐘浩,金基學 大邱敎育大學校 1992 論文集 Vol.27 No.-

본 연구는 육상경기의 중장거리경기 및 도약경기를 중심으로 과거의 기록을 분석하여 미래의 기록을 예측하고 남녀간의 기록차를 검토하기 위해서 행해졌으며, 그 대상이 된 기록은 1972sys부터 1990년 까지의 전국체육대회 고등부와 일반부의 100m,200m, 400m, 400m Relay, 800m,1500m 높이뛰기 및 멀리뛰기의 우승기록이다 경기기록의 예측은 1972년부터 1989년까지의 18년간의 기록을 기초로 해서 1990년, 1991년,1992년 및 2000년의 기록을 추정했으며, 1990년의 실제기록과 추정기록을 비교하고 전 기간을 통한 기록변화과정에서 성차가 검토되었다. 육상경기 기록의 추정과 성차에 대한 결론은 아래와 같다. 1. 회기 방정식의 회귀계수가 트랙종목에서는 -자로, 필드종목에서는 +로 되어 있으며 기록향상을 계속해서 이루어질 것으로 예측되지만, 단거리 일수록 기록단축의 범위가 좁고 중거리에서는 그 범위가 클 것으로 예상된다. 2. 여고부의 100m 및 남자 일반부의 100m와 400m를 포함한 대부분의 종목을 제외한 전종목에 걸쳐 비교적 추정의 精度가 높게 나타나고 여고부의 멀리뛰기는 가장 높았다.(R=0.9422) 3. 남자 고등부 멀리뛰기의 추정기록이 2000년에는 남자 일반부를 능가하게 되는 것으로 나타나고 있는데 이것은 과대평가 되어진 결과로 해석된다. 4. 전 종목에 걸쳐 남자 일반부의 기록 향상이 가장 저조할 것으로 보이는데 이것은 현재까지의 기록이 우리나라 선수로서는 기록의 최고치에 해당되는 한계선에 도달해 있는 것으로 사료된다. 5. 실측기록과 추정기록을 비교해 본 결과 아주 적은 차로서 추정기록이 실측기록보다 더 좋은 것으로 나타나고 있지만 비교적 추정의 精度가 높으므로 연도로서 장래의 기록을 거의 정확하게 추정할 수 있을 것으로 예상된다. 6. 단거리에서의 성차는 약 80-90% 정도이지만 2000년의 추정기록에서는 남자의 약 94%정도 근접해갈 것으로 보아 그 차는 약6%정도가 될 것이다. 7. 중거리에서 고등부는 현재 88%에서 2000년에는 94%로 근접해 가지만, 일반부에서는 83%에서 87%까지 접근해 가서 그 차는 약 13%정도가 될 것이다. 8.높이뛰기에서는 여고부의 기록향상이 남고부에 비해 저조하지만, 일반부는 2000년에 약 94%가 되어 기록 향상이 두드러질 것이다. 9. 멀리뛰기에서는 여고부의 기록향상이 남고부에 비해 저조하지만, 일반부는 현재 23%에서 14%로 접근해 갈 것이다. 10.경기기록 향상의 잠재성은 남자보다 여자가 더 클 것으로 기대된다.

유경성 대장 지방종의 내시경 절제 1예 (증례)

최종학 외 중앙대학교 의과대학 의학연구소 2007 中央醫大誌 Vol.32 No.1/2

Colon lipoma is a relatively rare benign tumor. Symptoms appear when its diameter exceeds 3 cm. Abdominal pain, constipation, rectal bleeding, colon obstruction and intussusception are clinical manifestations of colon lipoma. The traditional treatment for large colon lipoma is surgical resection. Also, colon lipoma can be resected endoscopically. However, removal of lipomas 2 cm or greater in size have been associated with a higher risk of perforation. We report a case of 5.5 cm pedunculated ascending colon lipoma which were removed by endoscopical resection, in a 66-year-old male with right lower quadrant pain.