콘크리트 포장의 플라이애쉬 재활용 방안연구

정영화,최성용,윤경구,용석응,김태경 강원대학교 석재복합신소재제품연구센터 1998 석재연 논문집 Vol.3 No.-

한국 대부분의 고속도로는 콘크리트로 포장되고 있으며, 플라이애쉬를 포장용 콘크리트에서 재활용하면 콘크리트의 성능을 향상시킴과 동시에 경제적 이익과 환경보호에 큰 기여를 할 것이다. 본 연구에서는 플라이애쉬를 포장 콘크리트에 재활용하고자, 플라이애쉬 치환율, 물-시멘트비, 굵은골재 최대치수를 주요실험 변수로 하여 이들이 플라이애쉬를 혼입한 포장용 콘크리트의 역학적 특성에 미치는 영향을 살피기 위해서 실험하여 통계처리 분석하였다. 이러한 분석결과를 바탕으로 포장 콘크리트의 적정배합을 제시하였으며 결과는 다음과 같다. 플라이애쉬를 혼입한 포장콘크리트의 휨강도에 영향을 미치는 인자는 플라이애쉬 치환율이 가장 큰 것으로 나타났으며, 다음으로 굵은골재 최대치수와 물-시멘트비 순으로 영향을 미친다. 또한, 플라이애쉬 치환율과 굵은골재 최대치수의 상관관계가 가장 큰 것을 알 수 있었다. 목표압축강도를 목표 휨강도의 6배로 선택하여 적정구간을 결정하였으나, 적정배합구간이 목표압축강도에 의해서 결정되었다. 이는 플라이애쉬의 작은 수화물이 공극을 효과적으로 채움으로써 휨강도의 증진에 크게 기여하기 때문으로 판단된다. 고속도로 포장에 적용할 수 있는 32mm의 굵은골재 최대치수와 45%의 물-시멘트비를 사용하는 목표 휨강도 45kg/㎠의 적정배합에서는 5.0%까지 플라이애쉬를 치환 가능하고, 50kg/㎠의 적정배합에서는 2.5%까지 치환 가능하다. 공항 포장에 적용할 수 있는 40mm의 굵은골재 최대치수와 37%의 물-시멘트비를 사용하는 목표 휨강도 45kg/㎠의 적정배합에서는 4.5%까지 플라이애쉬를 치환 가능하고, 50kg/㎠의 적정배합에서는 2.0%까지 치환 가능하다. The most of highway in Korea have been paved by concrete since last ten years. The recycling of fly ash in pavement concrete may result in economics, the improvement of concrete quality and the reservation of environment. This paper focused on the series of experiment and statistics analysis with experimental variables such as fly ash substitute ratio, water-cement ratio and maximum size of coarse aggregate in order to investigate the feasibility of recycling of fly ash in pavement concrete, to see the strength characteristics and t propose the optimum mix design based on previous results. The results of experiments and analysis were follows; The fly ash substitute ratio affected most seriously to the flexural strength of concrete among main variables, followed by maximum size of coarse aggregate and water-cement ratio. The interaction between fly ash substitute ratio and coarse aggregate size was the biggest. The optimum mix design was determined by target compressive, which was selected as 6 times of flexural strength. This indicated that the small hydrate of fly ash in concrete filled in effectively and resulted in the enhancement of flexural strength. the optimum mix design for highway pavement concrete with 32mm of maximum size of coarse aggregate and 45% of W/C can incorporate up to 5.0% and 2.5% of fly-ash at 45 kg/cm² and 50 kg/cm² of target flexural strength, respectively. The optimum mix design for airport pavement concrete with 40mm of maximum size of coarse aggregate and 37% of W/C can incorporate up to 4.5% and 2.0% of fly ash at 45 kg/cm² and 50 kg/cm² of target flexural strength, respectively.

원형 플레이트 형태에 따른 초음파 부상 장치의 진동특성에 관한 연구

정상화,최석봉,차경래,김현욱,김광호,박준호 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

In the semiconductor and optical industry the non-contact transportation is required for reducing the damages. The ultrasonic levitation is the solution of the problem. In this paper, the ultrasonic levitation system and 3 disk-type stator for levitation various object are proposed. The vibration modes of disks are analyzed with FEM and designed with the analysis results. The 3D vibration profiles of the disks are measured by Laser scanning vibrometer for verifying the vibration characteristics of the system. The amplitudes of the disks and the levitation heights of object are measured for evaluating the performance.

조선시대 감로탱화 풍속장면의 복식 연구

양숙향,이태호,이경화 한국의류산업학회 2003 한국의류산업학회지 Vol.5 No.5

The Gamrotenghwa of the Choson Dynasty is a unique genre of buddhist painting in that the destiny of the dead souls and the guidance to nirvana are expressed in reality. More than 50 of the Gamrotenghwa are known to he present, and the lower part of the paintings includes a wide assortment of folk customary scenes reflecting the social life style of the time when the painting was drawn, such as difficulties in life, public life, punishment and war. Changes in the costume of the people shown on the customary scenes of the Gamrotenghwa according to the time based changes in painting style were investigated in this study. The results are summarized in three points. First, the costumes of bureaucrats showed a tendency of preservation without any major changes in the painting. On the other hand, costumes of public and entertainer in the scenes were very close to those worn by the people at that time. The realistic description of public life in the painting may establish the value of the Gamrotenghwa as the historical documents. Second, the costume of the people in the painting showed a dual structure as the social positions; bureaucrats wore various official hats, large coats and belts to expose their social prestige, while the general public wore simple and convenient clothing which is divided into shirt and pants. The dual structure of the costume in the painting is in well accordance with that of the later period of Choson dynasty, suggesting that the customary scenes in the painting represent the social life style of the period. Finally, the customary scenes in the Gamrotenghwa are very variegated, which shows a variety of beauty of wearing even though they look coarse in a sense. The diversity of wearing beauty in the picture may contribute to the recreation of the beauty of shape in the new design of Hanbok.

한약재의 식중독균에 대한 항균효과

손동화,이석일,정영건 한국위생과학회 2001 한국위생과학회지 Vol.7 No.2

선별된 한약재의 타 식중독에 대한 항균성을 paper disc젖으로 조사한 결과 황백, 황련, 정향 모두 시험한 대부분의 식중독균에 대해 강한 항균력을 가졌으며, 특히 가장 발생빈도가 높은 Escherichia coli와 Staphylococcus aureus 에 대해 높은 항균력을 보이는 것으로 조사되었다. 이상의 결과로 볼 때 황백, 황련 및 정향의 추출물은 식중돗균에 대해서 강한 항균력을 보이는 것으로 인정되어 식품보존제로서의 이용 가능한 것으로 확인되었다. Water extracts of medicinal plants were prepared to investigate antibacterial activity on pathogenic bacteria, Water extracts of phellodendron amurense Ruprcht, Coptis chinensis Franch. and syzygium aromaticum (L.) Merr. et perry were exhibited excellent growth inhibiting activities for the most of tested pathogenic bacteria. The results suggest that extracts of phellodendron amurense Ruprcht, Coptis chinensis Franch. and syzygium aromaticum (L.) Merr. et perry couid play a good role for antimimicrobial agents food.

초등학교 특별보충과정 운영실태 분석 - 부산광역시 초등학교를 중심으로

전화춘,김석우 釜山大學校 敎育硏究所 2006 敎育硏究 Vol.16 No.1

발치와의 치유과정에서 교원질 및 비교원단백질의 분포에 관한 면역조직화학적 연구

오화탁,김현수,주성숙,신제원 慶熙大學校 齒科大學 1995 慶熙齒大論文集 Vol.17 No.2

During tooth socket healing, the coagulum in the socket is replaced by fibrous connective tissue which undergoes mineralization and eventually becomes bone. Using this model, the healing process of the tooth socket and the role of type I collagen(CI), fibronectin(FN), bone sialoprotein(BSP), and osteopontin(OP) in the process were studied. Thirty Sprague-Dawley rats weighing 130-150gm were fed fi -aminopropionitcille for 5days before extraction of the first maxillary molars, and sacrified by perfusion with 4% paraformaldehyde at 1, 3, 5, 7, and 10days after tooth extraction. The socket and surrounding tissues were cut, demineralized, dehydrated and embedded in paraffin. For morphological observation, the sections were stained by Azan. Immunostaining of the ECM components was achieved by the avidin-biotin complex method. The results as follows; 1. Morphology of the tooth socket 1day after tooth extraction. The socket was filled with blood coagulum which was composed of densly aggregated red blood cells, platelets and fibrin network. 2. Morphology of the tooth socket 3days after tooth exyraction. A large portion of the coagulum was replaced by fibrous connective tissue contains a large number of fibroblasts, come from periphery of the socket. 3. At 5days, the newly formed bone demonstrated the highest proliferation activity. At 7days, the soclet was occupied with new bone. 4. Type I collagen was observed in the newly formed connective tissue and around the new bone. fiber. 5. Intensive staining for fibronectin was observed in granulation tissue, especially around blood vessels as well as inflammatory cells. 6. Strong immunostaining for bone sialoprotein and osteopontin was found in osteoblasts and new bone, while weaker staining was observed on dense connective tissue. 7. These data suggest that collagen and noncollagen proteins (FN, BSP, OP) an important role daring socket healing.

다채널 광정렬 장치에서의 다자유도 회전 스테이지 동작 특성에 관한 연구

정상화,차경래,김현욱,최석봉,김광호,박준호 한국공작기계학회 2005 한국공작기계학회 춘계학술대회논문집 Vol.2005 No.-

In recent years, as the demands of VBNS(Very high speed Backbone Network Service) and VDSL(Very high-data rate Digital Subscriber Line) increase, the development of kernel parts of optical communication such as PLC(Planar Light Circuit), Coupler, WDM elements increase. The alignment and the attachment technology are very important to fabricate the optical elements for communication. In this paper, the mechanism of rotational stage are studied. with the three different method and the results of them are applied to the design of the system. The performance test of resolution and travel is performed.

다중처리 시스템에서 향상된 부하분산에 관한 연구

이성화,문석환 제주한라대학 2001 論文集 Vol.25 No.-

In this thesis, an advanced load balancing algorithm for distributed systems is presented. The distributed parallel processing has emerged as a key technology in modern computers for higher performance and lower costs. In ideal case, the performance of a distributed system will increase linearly with the number of processors. But actually, the performance curve is not ideal because of the saturation effect. In distributed systems, processors have different work loads for instance, some of the processors are idle while others are still working. This causes a degradation of the system performance. The load balancing is conducted by transferring some task from heavily loaded processors to lightly loaded processors. In this paper, an advanced load balancing algorithm in nth order Hypercube distributed system has been proposed. The new algorithm uses centralized load-balancing to avoid blocking phenomenon and processor thrashing, and shows the results which makes loads to approach average value of loads. The new algorithm is compared with several other algorithm and it shows a merit in cost function value.

12주 근력강화훈련 동안 표면근전도 신호의 특성

신화경,조상현,차광석 한국전문물리치료학회 2003 한국전문물리치료학회지 Vol.10 No.1

Ⅰ. 서론 Ⅱ. 연구방법 1. 연구대상 2. 실험설계 3. 근력강화훈련 4. 최대 근력의 평가 5. 표면근전도 신호 수집 가. 장비 설정 나. 표면근전도 신호 수집 6. 신호 처리 가. 주파수 스펙트럼 분석 나. 적분EMG 7. 통계분석 가. 정규화 나. 통계분석 Ⅲ. 결과 1. 근육 둘레의 변화 2. 적분EMG와 근수축력의 변화 가. 등척성 운동 나. 등장성 운동 다. 12주 동안 근력과 적분EMG의 변화 3. 초기중앙주파수의 변화 4. 피로지수의 변화 5. 회귀직선 기울기의 변화 Ⅳ. 고찰 Ⅴ. 결론 This study tested whether repeated measurement of median frequency (MDF)-related variables could express the muscle power changes during a 12-week DeLome strengthening program, by using consecutive overlapping FFT (Fast Fourier transformation) and integrated EMG (IEMG) from surface EMG data for isometric and isotonic exercise. To evaluate the effect of training, the following were recorded every 3 weeks for the elbow flexors and knee extensors of 5 healthy male volunteers: MVC, 1RM, limb circumference, and surface EMG during isometric MVC or isotonic contraction at 10RM load. From the EMG data, IEMG and variables from a regression analysis between MDF and time were obtained. MVC, 1RM, IEMG, and initial MDF increased linearly over the training period. The fatigue index and slope of the regression line increased temporarily until the 6th week and decreased thereafter. From these results, there appeared to be enhanced neural recruitment of fast twitch fibers in the first 6 weeks and continued enhancement in the recruitment and hypertrophy of fast twitch fibers, which led to increased fatigue resistance, over the last 6 weeks. Accordingly, the MDF and IEMG analysis technique could demonstrate the effect of the program detected significant changes in both isometric and isotonic contractions. EMG analysis methods can be used to estimate the electrophysiological and histological changes in skeletal muscles during a strengthening program.

무용수의 식사제한 후유증에 대한 생리학적 고찰

이석인,민경화 한국스포츠리서치 2004 한국 스포츠 리서치 Vol.15 No.6

In recent years, eating disorders have increased and are appearing at younger ages. Dancers are usually placed to maintain the low body weight according to the physical demand of choreography and performance schedules. Such chronic dietary restriction exerts a bad effect on the body of dancers, Leptin is a hormone involved with satiety and energy balance and imposed to be an anti-obesity factor, In this study, the problems of chronic dietary restriction made by ballet dancer have been reviewed in the viewpoint of the function of leptin. We have consider the prevalence of eating disorder and the sequelae of dietary restriction such as menstrual dysfunction, bone loss, and some nutritional deficiencies. The physiological approach would be complementary to the self-questionnaire methods to assess the true prevalence of eating disorder end nutritional status of dancers.