Development of a Reduction Algorithm of GEO Satellite Optical Observation Data for Optical Wide Field Patrol (OWL)

Sun-youp Park,Jin Choi1,Jung Hyun Jo,Ju Young Son,Yung-Sik Park,Hong-Suh Yim,Hong-Suh Yim,Hong-Kyu Moon,Young-Ho Bae,Jang-Hyun Park 한국우주과학회 2015 Journal of Astronomy and Space Sciences Vol.32 No.3

An algorithm to automatically extract coordinate and time information from optical observation data of geostationary orbit satellites (GEO satellites) or geosynchronous orbit satellites (GOS satellites) is developed. The optical wide-field patrol system is capable of automatic observation using a pre-arranged schedule. Therefore, if this type of automatic analysis algorithm is available, daily unmanned monitoring of GEO satellites can be possible. For data acquisition for development, the COMS1 satellite was observed with 1-s exposure time and 1-m interval. The images were grouped and processed in terms of “action”, and each action was composed of six or nine successive images. First, a reference image with the best quality in one action was selected. Next, the rest of the images in the action were geometrically transformed to fit in the horizontal coordinate system (expressed in azimuthal angle and elevation) of the reference image. Then, these images were median-combined to retain only the possible non-moving GEO candidates. By reverting the coordinate transformation of the positions of these GEO satellite candidates, the final coordinates could be calculated.

動力耕耘機 利用實態에 關한 硏究

崔圭洪 건국대학교 1979 學術誌 Vol.23 No.2

This study has been conducted to evaluate the present of power tiller utilization which is the main equipment among agricultural machinery supplied under the government's farm machanization program. 200 farmers are selected in Kimpo, Kanghwa country, to record their power tiller utilization during a full year from Feburuary 1st of 1978 to January 31st of 1979. The result has been analized and summarized as follows : 1.The average use of power tiller in a year was 79.41 days and net operation was 470.24 hours. 2.The peak of power tiller use came in October as 13.45 days, and net operation time was 103 hours which is 21.9 percent of annual use. 3.Above 7 hours of utilization were recorded during the monthes of June, October and November. 4.By the different operations, the peak utilizations were recorded in October for transportation and threshing, in May for tillage and in June for pumping. 5.The distribution of power tiller utilization for different operations was composed of 38.5%, 32.53%, 22.35%, 6.29% and 0.32% for transportation, tillage, threshing, pumping and deases controll respectively, 6.Oil consumption was calculated as 1.64 litters per hour for fuel and 0.085 titters per hour for lubricant. 7.Repair frequncy was 17.84 times, and an average annual repair cost was 20,499 won per unit.

動力耕耘機用 디젤 機關의 騷音特性

崔圭洪,李承奇,安義成 건국대학교 산업기술연구원 1994 건국기술연구논문지 Vol.19 No.-

국내에서 생산보급되고 있는 動力耕耘機用 8PS 디젤기관의 騷音 狀態를 파악하고자 消音器 전방 1m 위치 및 운전자 위치에서의 모터 구동시와 연소 구동시 각 회전수별 騷音을 측정 비교 분석하고 기관에서 발생하는 소음중 에너지 비율이 가장 높은 排氣音을 제어하기 위해 소음기를 부착시와 소음기 제거시 및 空洞의 體積을 변화시킨 경우의 각 回轉數別 騷音度, 燃料消費率, 出力 등을 측정 분석하여 현 소형 디젤기관의 騷音 減少方案 모색의 기초자료로 제시하고자 실시한 시험의 결과는 다음과 같다. 1) 機關의 回轉數가 증가함에 따라 騷音은 높아지는 것으로 나타났으며, 기존 機關의 경우 機械騷音은 85dB 이상으로 이의 騷音低減對策이 필요하다고 생각된다. 2) 消音器 附着時와 除去時 무부하 운전시와 전부하 운전시 騷音은 소음기 부착시가 제거시에 비해 각각 4, 13.1dB 정도 낮게 나타나 비교적 소음감쇄 효과가 높았다. 3) 空洞體積 變化에 따른 消音器別 騷音은 기존의 소음기 T-Ⅰ 보다 空洞의 체적을 증가시킨 T-Ⅱ, T-Ⅲ가 운전자 위치 및 소음기 전방 1m 위치에서 無負荷 運轉時 각각 1.9∼2.3dB 및 2∼2.8dB, 全負荷 運轉時 각각 4.9∼5dB, 7.1∼7.5dB 감소한 것으로 나타났다. 4) 각 회전수별 燃料消費率은 T-Ⅰ, T-Ⅱ, T-Ⅲ가 거의 같은 경향을 나타냈으나, 소음기를 제거한 경우는 약 17g/PS·hr 정도 낮게 나타났다. 또, 출력은 소음기를 부착한 경우가 제거한 경우에 비해 각각 0.55PS 낮게 나타났다. 5) 排氣騷音을 최대한으로 감소시키기 위하여 금후 機關出力 감소가 적고, 騷音 減少效果가 높은 形態의 消音器 開發硏究가 이루어져야 할 것으로 생각된다. This study was conducted to evaluate the noise characteristic of 8PS agricultural diesel engine through the modification, was found to provide the foundamental data that could be used to reduce the noise of the engine. To evaluate the noise characteristics on the agricultural diesel engine by the muffler, noise level, specific fuel consumption and output were measured in case of the with and without muffler and three different volume of muffler cavity. The results of the study are summarized as follows: The noise increased by the increament of revolution velocity. The mechanical noise of power tiller indicated more than 85dB at 1,800∼2,200rpm. Therefore, to minimized bearing ability of operator, it was thought that the countermeasure of noise reduction need. The noise level with the muffler was smaller than those without muffler by 4dB, 13.1dB. respectively. In case of increased the volume of muffler cavity, the noise level at the position of working seat was decreased 1.9∼2.3dB at the time of no-load condition and 4.9∼5dB at the time of full load, respectively. The specific fuel consumption of the without muffler type was 17g/PS hr lower than the with muffler type. The output of the without muffler type was 0.55PS higher than the with muffler type, respectively. To reduce of the exhaust noise, it is necessary to continue researches on the relationship between complex factors of the noise.

韓國産 野生油脂 植物의 디-젤機關 代替燃料 開發에 관한 硏究

崔圭洪,李麗夏,趙台煥,洪性珏 建國大學校附設 農業資源開發硏究所 1982 論文集 Vol.7 No.-

本 硏究는 國內에 自生하는 木本植物의 種實油로서 디젤 및 石油엔진의 代替에너지로 쓸 수 있는지를 調査하기 위해 시도되었다. 운향科, 대극科, 국화科 및 콩科에 속하는 몇몇 植物의 採油量과 代替에너지로서의 品質을 調査하였고, 아울러 採油하고 남은 油粕이 動物飼料로서 쓰일 수 있을지도 硏究하였다. 上記한 種實油 중 輕油 및 石油에 쉽게 溶解되는 쉬나무의 種實油만이 엔진試驗에 쓰일 수 있었다. 本 實驗에서 種實油는 輕油 및 石油와 0%∼100%까지 여러 단계의 比率로 혼합 사용되었으며, 이로써 엔진始動試驗, 最大出力, 全荷重 및 過荷重에서의 燃料消費率, 調速性能, 無負荷回轉數 그리고 排氣가스 내의 炭火水素(HC)와 一酸化炭素(CO)의 量을 측정하였다. 本 實驗의 結果는 다음과 같다. 1) 種實油의 含量은 쉬나무의 경우 40%이고, 예덕나무 41%, 산초나무 38.5%, 주엽나무 2.3%였다. 예덕나무와 산초나무의 種實油는 採油한 후, 곧 固化되어 輕油 및 石油에 溶解되지 않았다. 쉬나무의 種實油만이 輕油 및 石油에 잘 녹았으므로 이로써 엔진試驗을 實施하였다. 2) 輕油와 쉬나무 種實油의 比重은 각각 0.840과 0.932였다. 輕油와 種實油의 混合油의 比重은 混合比가 커질수록 낮아졌다. 이를 디젤엔진에 사용해 본 結果는 다음과 같다. ① 最大出力은 常用回轉數 2,400rpm에서 D.C. Dynanometer로 測定한 바 種實油 0%의 경우 6ps였고, 30% 種實油는 6.2ps, 50% 種實油는 6.55ps, 70% 種實油는 6.7ps, 90% 種實油는 6.6ps였다. ② 4/4 全負荷의 경우, 燃料消費率은 種實油 100%의 경우 239g/ps-hr로 최소였으며 30% 種實油는 250g/ps-hr, 0% 種實油는 253g/ps-hr, 50% 種實油는 256g/ps-hr, 90% 種實油는 257g/ps-hr 그리고 70% 種實油는 258g/ps-hr이었다. 11/10 過負荷의 경우 種實油 90%의 경우 251g/ps-hr로 최소였으며, 70% 種實油는 253g/ps-hr, 30% 種實油는 259g/ps-hr 50% 種實油는 261g/ps-hr, 0% 種實油는 279g/ps-hr 그리고 100% 種實油는 281g/ps-hr이었다. ③ 調速性能比는 種實油 0%의 경우 6%인데 비해, 種實油 30∼100%에 있어서는 5∼5.7%였다. 安定速度變動率은 種實油 0%의 경우 5%인데 비해, 種實油 30∼100%에 있어서는 1.9∼5.5%였다. 일반적으로 混合油는 순수한 디젤油에 비해 뛰어난 調速性能을 나타냈다. ④ 無負荷回轉時 엔진시험에 사용된 모든 燃料는 공히 高速 3.030rpm, 低速 600rpm으로 꼭 같았다. ⑤ 排氣가스內의 HC(ppm) 및 CO(%)의 양을 측정한 바 種實油 0%의 경우 各各 800ppm과 0.05%였고, 30% 種實油는 500ppm과 0.04%, 50% 種實油는 500ppm과 0.03%, 70% 種實油는 500ppm과 0.03%, 90% 種實油는 450ppm과 0.03% 그리고 100% 種實油의 경우는 400ppm과 0.02%를 나타내었다. ⑥ 엔진始動이 可能한 潤滑油 溫度는 種實油 0%의 경우 -10℃였고, 50% 種實油는 -5℃, 70% 種實油는 -2℃, 90% 種實油는 3℃ 그리고 100% 種實油의 경우 5℃였다. 그러나 暖機運轉 後에는 모든 경우에 있어서 外氣溫度 -10℃에서도 始動이 可能하였다. 3) 石油의 比重은 0.785였고, 쉬나무 種實油와 混合油의 比重은 種實油의 混合比가 커질수록 증가하였다. 石油엔진의 경우 種實油 10%의 混合油로 엔진始動이 可能하였으나 plug의 汚損이 심했다. 繼續運轉時 plug에 堆積된 炭素 때문에 pre-ignition 및 knocking 現象이 일어났다. 種實油 20%의 경우 不完全燃燒로 인해 back fire現象이 일어나고 muffler에서 火焰이 生成되며 knocking 現象이 심하게 나타났다. 種實油 30%의 경우 엔진은 겨우 始動되지만 種實油가 氣化器의 main nozzle, air bleed jet 및 slow nozzle에 붙어서 심함 hunting 現象이 일어나고 엔진이 停止되었다. 4) 採油하고 남은 쉬나무의 油粕은 24%의 蛋白質을 含有하여 動物飼料로써 이용될 수 있는 可能性을 보였다. 이상의 結果에서 보듯이 쉬나무의 種實油는 石油엔진에는 쓰일 수 없으나 디젤엔진의 代替에너지로는 훌륭할 것으로 思慮된다. To know the possibility of fuel substitution for diesel and kerosene engine with the seed oil from the woody plants native in Korea, the seed oil from Rutaceae, Euphorbiaceae, Compositae and Leguminosae was collected and examined in terms of the quantity and quality of the seed oil as the fuel substitute. The feasibility of animal feed substitution with the residuals after the oil extraction was also considered. Because of the solubility of the seed oil into diesel and kerosene, only the Evodia seed oil was used for the engine test. The seed oil was mixed with diesel or kerosene at the various ratioes; 0% to 100%, and the following tests were done; the engine starting, the maximum out-put, the fuel consumption rate each at the normal and over-loading condition, the governer performance, the rpm at the unloading condition and the content of hydrocarbon (HC) and carbon monoxide (CO) in the burned gas of the diesel and the kerosene engine. The following results were obtained. 1) The content of seed oil was 40% of the dry weight of the seeds with Evodia daniellii Hemsley, 41% with Mallotus japonicus Muell.-Arg., 38.5% with Zanthoxylum schinifolium S. et Z., 2.3% with Gleditsia japonica var. koraiensis(Nak.) Nakai. The seed oil from Mallotus japonicus and Zanthoxylum schinifolium became hard and was not soluble to diesel and kerosene. The seed oil from Evodia daniellii was easily soluble both to diesel and kerosene, so that the engine test was done only with the Evodia seed oil. 2) The specific gravity of diesel and the Evodia seed oil was 0.840 and 0.932 respectively. The mixed seed oil with diesel had proportionally lower specific gravity as the mixing percent increased. The following results were obtained with diesel engine. a) The maximum output of the diesel engine measured by D.C. Motoring Dynanometer at the 2400rpm of normal revolution was 6ps with the 0% seed oil, 6.2ps with the 30%, 6.55ps with the 50%, 6.7ps with the 70%, 6.6ps with the 90% and 6.6ps with the 100% seed oil. b) The rate of fuel consumption at the 4/4 normal loading was 239g/ps-hr with the 100%seed oil which had the least rate among the treatments and 250g/ps-hr with the 30%, 253/ps-hr with the 0%, 256g/ps-hr with the 50%, 257g/ps-hr with the 90%, 258g/ps-hr with the 70%. The consumption rate at the 11/10 overloading was 251g/ps-hr with the 90% seed oil which had the least rate, and 253g/ps-hr with the 70%, 259g/ps-hr with the 30%, 261g/ps-hr with the 50%, 279g/ps-hr with the 0% and 281g/ps-hr with the 100%. c) The coefficient of fluctuation of instantaneous speed was 6% with the 0% seed oil, while 5-5.7% with the 30% to 100%. The coefficient of fluctuation of stable speed was 5% with the 0% seed oil, while 1.9-5.5.% with the 30% to 100%. In general the mixed fuel showed excellent governer performance as compared with the pure diesel. d) Revolution at the unloading condition was 3030rpm at high speed, 600rpm at low speed in all combinations of oil-diesel mixture. e) The concentration of hydrocarbon(ppm) and carbon monoxide(%) was respectively 800ppm and 0.05% in the 0% seed oil, 500ppm and 0.04% in the 30%, 500ppm and 0.03% in the 50%, 500ppm and 0.03% in the 70%, 450ppm and 0.03% in the 90%, 400 ppm and 0.02% in the 100%. f) The lowest engine oil temperature at which the engine can start was -10℃ with the 0% seed oil, -5℃ with the 50%, -2℃ with the 70%, 3℃ with the 90% and 5℃ with the 100%. However, in case of using prewarmed engine, there were no difficulties in starting engine with all combination of oil at the air temperature of -10℃. 3) The specific gravity of kerosene was 0.785 and that of the mixture with the Evodia seed oil increased as the percentage of the seed oil increased. The kerosene engine was able to start with the 10% seed oil kerosene, but the plug was easily contaminated. On the continuous running, the pre-ignition and knocking occured because of the carbon accumulation at plug. With the 20% seed oil, incomplete combustion caused back fire, flame and knocking at the muffler. With the 30% seed oil, the engine was able to start with difficulties and the seed oil which sticked on the main nozzle, air bleed jet and slow nozzle in the carburetor caused serious hunting and the engine stopped. 4) The protein content of the Evodia seed residuals after the oil extraction was 24%, suggesting that could be used as animal feed. The above results suggested that the seed oil from Evodia daniellii can not be used in the kerosene engine but excellent fuel substitute in the diesel engine.

이유백서에서 교근절제후 하악과두의 면역조직화학적 연구

최남기,양규호,최홍란 大韓小兒齒科學會 1996 大韓小兒齒科學會誌 Vol.23 No.2

The purpose of this study was to determine whether there was any correlation between temporomandibular joint dysfunction and structure of the mandibular condyle. Weanling rats had their masseter muscles resected and immunohstochemical findings were observed with a light microscope. The results obtained were as follows: 1.The condylar cartilage region was divided into articular,proliferating,cartilage cell and hypertrophic cell layers according to cell morphology. 2.In light microscopic views,the proliferating and cartilage cell layers of the experimental group decreased gradually and at the 8th week significantly. 3.In immunohistochemical staining for type Ⅰand Ⅱ collagen,a reaction was detected in the lower part of proliferating cell and cartilage cell layers.In the cartilage cell layers,a stronger cellular reaction was present.Immunohistochemical staining for type Ⅱ collagen reacted more strongly than that Ⅰ collagen. 4.In immunohistochemical staining for proteoglycan,the staining of the experimental group resembled the control group and gradually showed a weak reaction.The proliferating and cartilage cell layers reacted more strongly then hypertrophic cell layer. 5.In immunohistochemical staining for proliferating cell nuclear antigen(PCNA),the strong reaction was detected in the nucleus of the proliferating cell layer both in control and experimental groups.But the thickness of the proliferating layer decreased in experimental group,consequently the reaction of the experimental group was reduced more than that of the control group.

麥類條播機用 上向切削 로터리의 碎土性과 所要動力에 關한 硏究(Ⅰ)

崔圭洪,洪顯裕,李承奇 建國大學校 附設 農業資源開發硏究所 1993 農資源開發論集 Vol.18 No.-

본 시험은 麥類畦立細條播機 逆回轉 로터리 作業時 耕深을 16cm로 고정하고 耕耘 피치 및 토양수분 차이가 PTO軸의 토크와 所要動力 排水溝의 형상 및 쇄토율 등에 미치는 영향을 구명하기 위하여 벼 수확을 마치고 벼그루가 남아 있는 埴壤土의 논에서 시험을 실시하였으며 주요 결과는 다음과 같다. 1) PTO軸의 平均토크 및 最大토크는 토양수분에 따라 차이는 있지만 逆回轉 로터리의 耕耘 토크는 耕耘 피치 6cm이하에서는 耕耘 피치 증가에 따라 직선적으로 증가하지만 耕耘 피치 6cm이상에서는 耕耘 피치 증가에 관계없이 거의 일정한 경향이었다. 2) 作業速度와 排水溝 殘存흙 및 覆土狀態는 逆回轉 로터리의 주행속도가 느릴수록 또 PTO回轉速度가 빠를수록 양호하여 주행속도 1단 PTO 3단에서 가장 좋게 나타났다. 3) 쇄토율은 耕耘 피치가 증가할수록 또 토양수분이 높을수록 쇄토율은 떨어지는 경향이었으며, 충분한 碎土程度를 얻기 위하여는 耕耘 피치를 3cm이하로 하고 가능한 토양수분 함량 31.7%(d.b) 이하에서 작업하는 것이 좋을 것으로 판단되었다. 4) PTO軸의 所要動力은 작업속도 1∼4단 로터리 變速段數 1∼3段에서의 PTO軸 所要動力은 토양수분 38.0%(d.b)일 때 5.1∼14.5ps, 35.5%(d.b)의 경우 7.9∼14.2ps, 31.7%(d.b)일 때는 4.6∼12.7ps로 나타나 토양수분이 증가할수록 소용동력은 증가하다가 다시 감소하는 경향이었다. 5) 覆土狀態는 耕耘 피치가 적을수록 양호하여 주행속도 1단 PTO 3단의 경우 가장 좋았으며, 작업능률면을 고려할 때 排水溝 程度, 覆土狀態, 所要動力 및 作業能率 등을 고려할 때 畦立 로터리 파종작업시 PTO變速段數는 3단으로 하고 주행단수는 토양수분 함량 31.7%(d.b) 내외에서는 3단, 토양수분함량 35.5%(d.b) 내외에서는 2단, 토양수분 함량 38.0%(d.b) 이상에서는 1단으로 작업하여야 할 것으로 판단된다. This study was carried out to investigate the soil pulverization rate and power requirement of up-cut rotary of wheat and barley drill seeder for tractor by tilling pitch and soil moisture content. The experiment was conducted in the paddy field of clay roam remaining stem of paddy rice after harvesting. The results are summarized as follows: 1) Average and maximum torque of PTO shaft was increased in proportion with tilling pitch in less than 6cm, but was apt to definite over than 6cm of tilling pitch. 2) The working speed, status of remaining and covering soil in drainage was good in proportion with decrease the travelling speed of up-cut rotary and increae the revolutions per minute. Therefore, the working status in drainage was best in forward first gear and PTO third stage. 3) The soil pulverization rate was decreased according to increase the tilling pitch and soil moisture content. It was concluded that tilling work in 31.7 percent of soil moisture content and less than 3cm of tilling pitch would be good. 4) The power requirement of PTO shaft by soil moisture content were 5.2∼14,5ps in 38.0 percent, 7.9∼14.2ps in 35.1 percent and 4.6∼12.7ps in 31.7 percent soil moisture content. So the power requirement of PTO shaft was apt to increase in proportion with soil moisture content the first and decrease the last. 5) The status of soil covering was good in forward first gear and PTO third stage. When it was considered the status of drainage, covering the soil and power requirement in working performance, it was concluded that the PTO stage would be third and working speed would be forward third gear in 31.7 percent, forward second gear in 35.5 percent and forward first gear in 38.0 percent of moisture content.

UID설계의 지원수단과 방법에 관한 연구

崔明植,閔珪泓 경희대학교 부설 디자인연구원 1998 예술· 디자인학연구 Vol.1 No.1

If there is only a whole simple equipment like a light built in a simple function around us, neither happening will occur to us nor UID theory will be useful. But recently equipment supplied to home or office have complicated and various functions, besides become miniaturization. In one word, additional functions in comparison with the limited factor of design is becoming various. While varied functions give high added value, they cause new problem not only in the stage of design but also in users, and rather raise the problem for use. This kind of tendency is a new problem causing from the functions of recent electric appliances and is a example of raising problem rather than convenience on functions. Most of users might have experience the decline of operation causing by too many additional functions. This study considers what kind of factor we need for the design of the interface with rough contents of the method on the interface design, and examines what field of knowledge we need for the design of UID.

고등학교 지리교육과정운영의 특징과 개선방향 : 강원도지역의 제7차 교육과정시행을 중심으로 Focused on the Enforcing of the 7th Curriculum in Gangweon-do Area

최홍규 한국지리환경교육학회 2003 한국지리환경교육학회지 Vol.11 No.2

7차 교육과정에서 지리교과는 국민공통교과인 사회, 일반선택교과인 인간사회와 환경, 심화선택교과인 한국지리, 경제지리, 세계지리로 구성된다. 현행 통합사회과는 지리영역과 일반사회영역이 하나가 된 영역별 통합교과로서 함께 교수를 하면 비전공영역이 있게 되고, 분과별과 교수하면 교육과정 시행상에 위배가 되는 결과를 낳는다. 지리교사들은 통합사회과 운영이 성공적이지 못하다고 생각해서 철저히 분과적 운영을 원하고 있다. 또한 7차 교육과정의 통합사회과에 대비한 교사들의 준비가 미흡해서 학습자들에게 교육적인 피해를 줄 수 있는 구조적인 문제를 가지고 있다. 그렇기 때문에 지리교사들은 통합사회과 운영을 위해 주로 방학중 연수를 통해서 준비를 많이 하고 있으며 교육과정을 시행하기 전에 미리 체계적인 교사 연수를 하거나 교원양성대학의 교육체계가 개선되어 준비가 되기를 강력히 원하고 있다. 아울러 교육과정을 개정할 때는 학교 교육환경과 지리교사들의 의견을 충분히 참작하여서 현실감있고 실현 가능성 있는 교육과정이 준비되도록 노력해야만 하겠다. 지리교육을 통해서 학습자들에게 내면화될 가치관과 일상생활에서 적응하여 표출될 삶의 태도가 잘 형성되도록 학습자료와 교수학습 방법을 개선해 가야만 하겠다. In the 7th Curriculum, Geography consists of Social Studies(a national common subject), Human Society and Circumstances(a general selective subject), Korean Geography, Economic Geography, and World Geography(special selective subjects). Among these subjects, integrated Social Studies, which is composed of two categories, Geography and General Society, has two major problems; one is that there is a danger that non-majoring teachers may teach students when teaching as an integrated subject, and the other, that there may come a result that teachers go against the spirit and the rule of the 7th Curriculum when teaching as a divided subject. The most Geography teachers, thinking that it is unsuccessful to teach the subject as an integrated one, want positively Social Studies of the 1st graders to be instructed as a divided subject. And they insist that the integrated subject has structural faults and that they should have been prepared for the subject before the curriculum started. Curricular revision should take place, based on reality and realizability, with education circumstances of schools and opinions of Geography teachers fully considered in advance. Geography teachers should improve their teaching materials and teaching-learning methods in order for learners to form well the view-points inwardly and the attitudes for life outwardly through Geography education.

고체용 펄스핵자기공명 실험에 대하여

최규상,홍관수 順天大學校 師範大學 附屬 科學敎育硏究所 1995 科學과 敎育 Vol.3 No.-

Nuclear magnetic resonance(NMR) is a discipline of non-destructive radio-frequency spectroscopy ranging from physics and chemistry to biology and engineering. NMR consists of two parts; cw NMR and pulse NMR. pulse NMR is superior to cw NMR in various respects. We introduce briefly the basic theory and physical quantities of pulse NMR, and what can be known from these. The apparatus used is MSL200 for solid NMR, which is located in KOREA BASIC SCIENCE INSTITUTE SEOUL BRANCH.

農業機械 主要部品의 機械的 性質에 關한 硏究(Ⅰ)

崔圭洪,權純洪 建國大學校 附設 農業資源開發硏究所 1991 農資源開發論集 Vol.16 No.-

본 실험은 農業機械의 性能 및 耐久性에 밀접한 관계를 가지며, 素材의 品質面에서 구성하고 있는 化學成分이 韓國工業規格에 적합치 못한 주요 부품의 材料에 대한 機械的 性質을 조사하여 良質素材의 安定供給을 위한 素材産業의 육성과 이에 따른 優良農業機械의 生産供給으로 素材에 의한 品質低下 要因이 발생하지 않도록 그 基本資料를 제시하고자 실시하였으며, 분석한 결과를 요약하면 다음과 같다. 1) 一般鋼材 및 特殊用鐵鋼을 材料로 사용하는 부품은 素材別로 機械的 性質이 좋지 못한 것으로 나타났다. 2) 鑄物類를 素材로 하고 있는 부품은 모두 저급의 材質을 사용하고 있는 것으로 나타났다. 3) 小規模 群小業體가 生産供給하는 機種의 부품에 사용되고 있는 재료는 대단히 불량한 것으로 나타나 이에 대한 素材의 品質向上 및 良質素材의 安定供給을 위한 素材産業의 육성이 절실한 것으로 생각된다. These studies were carried out to investigate the mechanical properties for the major part in agricultural machinery in order to bring up the material industry and for the factor of quality drop not to happen to Korean farm machinery. The results are as follows ; 1) Carbons Steels and special purpose steels used in the major parts in agricultural machinery were inferior materials in mechanical properties. 2) Alloy castings used in the major parts were unsuitable to mechanical properties. 3) The attachments for working machinery, power sprayer, thresher, straw cutter, which were manufactured by small makers, were not suitable to the major parts in agricultural machinery. I think that urgent problems are the improvement of quality control in materials and the upbringing of the material industry in order to stabilize the supply of good quality materials in Korean farm machinery.