석탄회의 MR 특성

朴興奎 관동대학교 1993 關大論文集 Vol.21 No.2

This paper is to elucidate the MR-CBR correlation and stress-strain behavior of coal ash throught the MR test. We've tried to check the possibility of the massive use of coal ash as a construction material, and so gathered to experiment the coal ash from a few thermal power plants and the weathered granite soil in the middle area of the peninsula. The results are: 1. MR properties of weathered granite soil and bottom ash are found as in sandy soil. 2. The change of the value of CBR is to be considered in order to get the MR value from the CBR value of coal ash.

石灰混合土의 壓縮强度에 關한 實驗的 硏究

朴興奎 관동대학교 1984 關大論文集 Vol.12 No.2

This study was attempted in order to search for unconfined compressive strength of Lime-Soil Mixtures, physical, chemical and mechanical test were conducted to find out the standard properties of soil to be used. Various lime contents used in this test were 3%,6%,9% and 12%, and the compressive strength was tested after 7days, 14days and 28days of standard curing in the above each lime content respectively. Obtained the results summarized as follows. 1. Lime content between strength was obtained as follow; OD Soil q=1.511L+13.2(r=0.465) KL Soil q=1.333L+9.0(r=0.500) OL Soil q=1.500L+8.0(r=0.483) 2. In molding the specimens with the optimum moisture content, the maximum strenght appeared at the wet side of the optimum moisture content. 3. According to increase of curing days, unconfiend compressive strength of Line-Soil mixtures increased the rate of increase of the early curing period was large, but approximately 7 day was surfficient to harden Lime-Soil mixtures completely. 4. Optimum moisture content increased with increase of the lime content, but maximum dry density decreased with lime content.

石炭灰의 建設材料로서의 活用에 관한 硏究

朴興奎 관동대학교 1990 關大論文集 Vol.18 No.1

In order to utilize coal ash, which we go to great expense to scrap, as subbase course material in tetms of improving its technological properties with the addition of some cement. this study attempts to examine the deformation characteristics of coal ash when repeated loads are applied. The material of coal ash is obtained from Young Dong thermal power plants. The results are: Unconfined compression strength shows rectilineal increase in propotion to the cement addition ratio. Within the repeated loads of 3×10? times, modulus of elasticity tendsto decrease while compression strength shows about 21% increase.

花崗岩質風化土의 흙시멘트에 關한 硏究 : 다짐試驗에 의한 壓縮强度 An Unconfined Compression Strength by Compaction Test

朴興奎 관동대학교 1985 關大論文集 Vol.13 No.3

This study was attempted in order to search for the properties of the cement mixture with weathered Granite soils. Physical and mechanical tests were conducted to find out the standard properties of the used soil. Various cement contents used in this test were 6%, 8%, 10% and 12% and the compressive strength was tested after 7 days, 14 days and 28 days of standand suring in the above each cement content respectively. The results obtained are summarized as follows. 1. Optimum moisture content and maximum dry density increased with increase of the cement content but was changed ununiformly with cement content. 2. The compressive strength was increased with the cement content and compaction number. 3. As the cement contents were creased, the compressive strength of the cement Mixture with weathered Granite soil were almost proportianlly increased.

고화재로 인정처리된 연약지반의 동결융해 특성

朴興奎 관동대학교 1997 關大論文集 Vol.25 No.2

In order to utilize soft clay, as subbase course in terms of improving its technological properties with the addition of some ESC. the study attempts to examine Durability of ESC stabilized soft clay when repeated Freezing & Thawing and Wetting & Drying. The results are : Unconfined compression Strength shows rectilineal increase in propotion to the ESC addition ratio. At the same percentage of added additions, Compressive strength of ESC is larger than cement. According as the number of freezing and thawing cycle increased, the lower compressive strength at 7 day was, the larger decrease of compressive strength was. Specimen which had high strength at 7 day and much added ESC was shown low rate of decrease of strength according to freezing and thawing cycle.

평균대 운동이 청각장애아동의 균형에 미치는 영향

박흥규,황병용 용인대학교 자연과학연구소 2003 自然科學硏究所論文誌 Vol.8 No.1

The purpose of this study was to determine the effects of exercise on a balance beam for the children with hearing impaired. The subjects were recruited by 20 children with only auditory deficit Measurements of the balance were taken by One Legged Stance Test (OLST), Functional Arm Reach Test (FART), Backward Walking Test (BWT), and Timed Up Go Test (TUGT). There were significant differences in BWT with eyes open and closed, and in TUGT after the exercises on a balance beam. There were no statistical significant differences between static exercises and dynamic exercises of children with hearing impaired in OLST, BWT with eyes closed, and TCGT. From the results we conclude that exercises on a balance beam influenced on improving balance proficiency of children with hearing impaired, but there were no differences between static exercises and dynamic exercises on a balance beam.

添加劑가 시멘트 및 石炭混合土의 壓縮强度에 미치는 影響

朴興奎 관동대학교 1988 關大論文集 Vol.16 No.2

The activation of the various construction works, together with the rapid growth of our national economy, has caused the ever increasing demand of good aggregate(such as sand, gravel ect) which is quite essential to the construction and it`s an impending everyday problem how to get a good kind of aggregate Therefore, in the sites where we cannot properly find the desirable aggregate, we improve the quality of the soil in terms of mixing cement or lime with soil, which is rather easily found nearby, and apply the mixture instead to the construction. However, we notice that the stabilized cement and lime mixtures show some defects in strength and durability as well as shrinkage crack, Thus, the present study, in order to see the problems clearly, try to examine the effect of additives upon the cement-soil and Lime-soil mixtures by changing the amount of each of the six additives. we`ve picked the soil as test material at the eastern part of the country.

오스템퍼 처리한 구상흑연주철의 드릴가공 특성과 공구수명에 관한 연구

조규재,이승수,전언찬,박흥식 동아대학교 공과대학부설 생산기술연구소 1996 生産技術硏究所硏究論文集 Vol.1 No.2

Drilling tests were carried out austempered ductile cast iron(ADI) to clarify the factors influencing the drilling chracteristics of ADI material. The machinability of material was evaluated using high speed steel drill and cobalt contained drill of 6mm diameter. The spherodal graphite cast iron materials were austenized at 900℃ for in hour and then wear was kept at 375℃ for 2 hours. Austempered ductile cast iron contains a great deal of retained austenite which contributes to an improvement of impact strength. In this paper, machinability of ADI was investigated by drilling experimentation. The results obtained are as follows: a) Flank wear increases logarithmically with the increases of cutting time. b) Relation of flank wear and cutting force can be applied to FZ = 925VB + 820 for the cutting suggested condition. c) Drilling hole number of about 2 times can be reduced more step feed than ordinary feed due to the high hardness of ADI material and hardness increasing ascribed to the martensite of retained austenite.

단무지 공장에서 발생한 질식 사고의 원인과 방사선학적 소견: 중례보고 및 가스분석 결과

박충기,김만구,김흥철,안범규,박만수,황우철,최철순,강익원 江原大學校 附設 環境硏究所 1994 環境硏究 Vol.11 No.-

목 적:단무지 공장에서 질식사고를 일으켰던 가스의 종류를 알아내고, 이러한 가스중독의 방서선학적 소견을 소개하기 위하여 본 연구를 하였다. 대상 및 방법:단무지 공장에서 발생한 질식 사고자 3예중 생존자 1예를 대상으로 단순흥부X-선검사와 CT 소견을 분석하였으며, 가스의 종류를 알아내기 위하여 단무지를 유리병에 넣어 발생된 가스를 가스크로마토그래픽을 이용하여 분석하였다. 결 과:단무지 공장에서 발생한 질식사고자중 생존한 1명의 방사선학적 검사에서 신속히 호전되는 폐경결(consolidation)을 볼 수 있었으며 이는 폐부종의 소견임을 알 수 있었다. 협기성 상태에서 단무지를 담은 유리병의 상층부 가스를 실험 분석한 결과 이산화탄소, 에칠알코올이 다량으로 검출되었으나 독성가스는 주로 황화수소이였다. 결 론:단무지 공장의 질식 사고자에서 폐방사선학적 소견은 폐경결을 보이는 폐부증으로서 이는 실험을 통해 단무지에서 발생되는 유독가스인 황화수소 때문임을 입증하였다. Purpose: To identify the main toxic gas released from salted radish in rice bran(Dan-M-Ji) and to introduce the radiological findings of the patient who was exposed to the gas. Materials and Methods: Chest radiographs and CT scans of one survivor among three men who were exposed to the gas from Dan-Mu-Ji were reviewed. Gas obtained from the closed bottle containing Dan-Mu-Ji was analized by using the gas chromatography. Results: The radiographlc examinations of the survivor were suggestive of pulmonary edema with it's rapidly improving consolidations in both lung. The headapace gas within the bottle containing Dan-Mu-Ji was mainly composed with carbon dioxide, ethyl alcohol and hydrogen sulfide, of which hydrogen sulfide was considered the main toxic gas released. Conclusion: Under the anaerobic condition, Dan-Mu-Ji released toxic hydrogen sulfide. Inhalation of hydrogen sulfide might produce non-cardiogenic pulmonary edema.

3상 유도전동기 구동을 위한 전압원 인버터의 새로운 과변조 PWM 기법

신흥교,박종규,김봉식,신휘범 慶尙大學校 工科大學 自動化및컴퓨터應用技術硏究所 1997 自動化 및 컴퓨터應用技術 Vol.4 No.1

The novel PWM(pulsewidth modulation) strategy of three-phase voltage source inverter in the overmodulation range is proposed. Generally, the space vector PWM strategy in the overmodulation range is widely utilized due to its simple and effective digital implementation and increased voltage transfer ratio. A unique algorithm manages the transition form the onset of overmodulation to six-step operation. This proposed technique maximizes the utilization of the dc-link voltage and maintain the voltage linearity between the reference and output voltages, and it decreases the necessary memory quantity for the look-up table of the angle.