난연성 FREP로 휨보강된 철근콘크리트 보의 구조성능 평가

강기연,최기선,한상환,유영찬 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.1(구조계)

The purpose of this study is to evaluate the flexural strengthening performance of the iFREP(incombustible Fiber Reinforced Epoxy Panel) to the reinforced concrete flexural members. The tensile strength of iFREP including mechanical and physical properties of the epoxy resin for injection were tested preliminary to investigate the material properties of iFREP constitutions. Also the bond characteristics of iFREP to the concrete were estimated to acquire the basic design data for strengthening through various bonding tests. Finally full-scale RC beams strengthened by iFREP were tested monotonically upto failure to evaluate the strengthening effects of iFREP to the RC flextural members. The main variable of the four test specimens was the thickness of iFREP. From the test results, it was found that the failure mode of RC beams strengthened by iFREP was governed by the fracture of iFREP indicating the sufficient bond strength of iFREP to the concrete. Also flexural strengthening effects of iFREP to the RC beams is proportional to the thickness of iFREP.

충청도 지역 일대 저품위 질석의 팽창 특성에 관해서

강헌찬,김영훈,김광수,신선명 동아대학교 건설기술연구소 1996 硏究報告 Vol.20 No.1

The propose of this thesis was to study the usage of the low-grade Vermiculite from the Chung Chong province and also to increase its Value-added. A series of experiments have been done for separation as well as heat-expansion characteristics of the Chung Chong Vermiculite some conclusions can be drawn as follows; 1. Vermiculite from Chung-Yang and Hong-Shung areas wear better than that from Palabora's mine in South Africa in terms of the usefulness for an organic fertilizer. 2. The ratio of the volume expansion of Vermiculite increased along with the temperature. 3. In general, the ratio of volume expansion of the vermiculite from Chung-Yang, Hong-Shung and Palabora's mine in South Africa increased with temperature. But it decreased temporarily in the vicinity of 850℃. The result seems to be due to temporary decrease in the latent heat as the crystal water in the crystals such as Ca_(10)(Mg,Fe)₂A1₄Si_(9)O₃₄(OH)₄, K(Fe,Mg)₃AlSi₃O_(10)(OH)₂and K (Fe,Mg)₃AlSi₃O_(10)(OH)₂evaporated. 4. Above 1050℃, the crystal structure began to change and resulted in partial destruction to produce some dusts. Finally sintering occurred.

양식장 배출물 발효물의 어류 사료 첨가에 따른 넙치, Paralichthys olivaceus의 혈액학적 변동에 미치는 영향

강주찬,지정훈,송승엽,문상욱,강지웅,이영돈,김세재 한국어병학회 2004 한국어병학회지 Vol.17 No.1

본 연구는 우리나라 주요 양식어류인 넙치, Paralichthys olivaceus를 대상으로 육상수조식양식장 배출물 발효물의 어류 사료 첨가에 따른 혈액학적 변동에 미치는 영향을 검토하였다. 젖산균 및 효모를 사용하여 발효한 양식장 배출물의 이화학적 분석을 실시하였고, 발효물을 0.1, 0.5, 1.0 및 5.0% 농도로 8주간 투여하였다. 투여 4주째 및 8주째에 각 투여 구간별로 혈액학적 항목을 중심으로 그 차이를 확인하였다. 배출물 발효농도별 유의한 차이는 나타나지 않았지만, 분석시기에 따른 적혈구수, 혈색소 농도 및 혈색소 지수가 증가하는 경향을 나타내었으나, 주요 혈청 무기 및 유기성분은 배출 발효물 농도별로 유의한 차이는 나타나지 않았다. 또한 혈청 효소학적 조사에서는 조사시기별로 변동은 나타났지만, 동일 조시시기에서 각 구간별 유의한 차이는 나타나지 않았다. 따라서 이러한 육상 약식장 유래의 배출물 발효산물에 대한 다양한 방면의 연구가 진행되어야겠다. Effects of oral administration with fermented product from sewage in land-based seawater fish farm on haematological disturbance in the olive flounder, Paralichthys olivaceus was investigated. After 4 weeks of conditioning with a basal diet, fish were divided into 4 groups and provided experimental diet (0.1,0.5, 1.0 and 2.0%) supplement of fermented sewage for 80 days. Proximal analysis was performed for the product of sewage which was fermented by lactic acid and yeast. RBC count, hemoglobin concentration and hematocrit value were increased according to the treated periods, however, no statistical difference was observed between control and treatment groups. There were no significant difference in serum organic, inorganic compounds and enzyme activities between control and treatment groups. This study hypothesized that the supplement of fermented product from sewage in land-based seawater fish farm might be an additive sup plement for source of fish diet in view of haematological examination. Recycling of the sewage may be an economic artificial sources of diet for fish aquaculture practices.

단음절 합성단위음을 사용한 시간영역에서의 한국어 연속음 규칙합성에 관한 연구

강찬희,안영화 江南大學校産學技術硏究所 2004 산학기술연구소논문집 Vol.- No.18

본 논문은 시간영역에서의 한국어 연속음 규칙합성에 관한 실험적 연구결과이다. 특히, 단음절 단위음을 사용하여 연속음을 합성할 경우 음절간의 피치 불연속성으로 인한 자연성 및 음질이 저하되는 현상을 개선하고자 하였다. 이를 위하여 자연음으로부터 추출한 구문 단위의 피치 패턴을 보간법으로 생성시켜 합성하는 방법을 제안하였다. 중심주파수가 80, 118, 140, 170, 200Hz인 5가지 유형의 피치 패턴을 2음절어 및 3음절어에 각각 부여하여 합성시킨 합성음에 대한 MOS평가를 수행한 결과를 제시하였다. 실험결과, 제안한 시간영역에서의 합성방식에 의한 합성음의 음질은 명료하고 자연스러웠으며, 간단한 문장단위의 연속음 합성이 가능하였다. 운율요소의 제어결과는 지속시간(장단)과 악센트(강약)와 피치주기(억양) 및 에너지 패턴의 제어도 시간영역에서 가능하였다.

UASB에 의한 有機性 廢水處理의 溫度影響에 관한 硏究

姜龍太,崔廷宇,全裕燦 東亞大學校 海洋資源硏究所 1991 硏究論文集 Vol.4 No.1

The purpose of this research was to investigate the effects of temperatures on the wastewater treatment. The experimental results used synthetic wastewater showed that removal efficiency of UASB ranged from 83 to 93 percents within a temperature ranges of 20 to 35℃, which indicated that the removal rates decreased approximately 2 or 3 percent as the temperatures reduced at intervals of 5℃. The production of waste sludge was a little, on the other hand, the treatment efficiency of it was very high. Obtained from this experimentation the values of temperature characteristic term(θ), Q?? and activated energy(E??) were 1.053, 1.69 and 9349cal/mole, respectively. We could find out the size and concentration of granular sludge decreased in proportion to the reduction of temperature, and a filamentous bacteria of Methanothrix spp. was prevailed more than a bacteria of other species in the granules.

花崗岩으로 부터 雲母의 浮選

강헌찬,남영숙 동아대학교 공과대학 부설 한국자원개발연구소 1990 硏究報告 Vol.14 No.2

Batch flotation test of Mica been conducted for the Granite sampled at near Buyeo. Two types of collector were used for the test : anionic type collector ; petroleum sulfonate and cationic type one ; coconut fatty amine oleate. The results of study are as follows. In case of using coconut fatty amine oleate, the Mica has been recovered up to 90% with its grade of 95%. In was achieved under the condition of using coconut fatty amine oleate in the range between 400/T and 750g/ T at pH2.5-3.0. In case of using petroleum sulfonate type, the rate of recovery and its grade are for loss than the above (recovery=50%)

식품공장폐수의 활성오니처리중 오존에 의한 산화분해효과

강경수,최영찬,하진환,송대진 濟州大學校 工科大學 産業技術硏究所 1991 産業技術硏究報告 Vol.2 No.-

For the increase of treatment efficiency when waste water which included residual chlorine was biologically treated with activated sludge, elimination efficiency of COD and change of transmittance by activated sludge method were examined after the treatment of residual chlorine with ozone of 100 volt and l0ℓ-air/min., 0.8g-0_(3)/hr. in velocity. The results were as follows. 1) When the sample which included residual chlorine was treated with ozone of 0.8g-O_(3)/hr., COD removal rate by the change of pH and ozonization time was more efficient than acidity solution of pH 3.2(20%) and alkaline solution of pH 12.0(10%). Since the COD removal rate become 35% after 50 minutes of ozonization time at neutral solution of pH 7.2. 2) After the residual chlorine included sample was treated with ozone for 50 minutes to make the F/M rate of 0.1㎏·BOD/㎏·MLSS, the sample was reacted with activated sludge for 3, 6, 9 and 15 hours. The 6 hours reaction gave 85.8% COD elimination which showed higher efficiency than 60.5% by Na_(2)S_(2)O_(3) treatment togather with shorting efficiency of reaction time. 3) When such sample as polyphenol which gives dark brown color was treated with ozone for 50 minutes after being made into acidic, neutral and alkaline solution. the transmittance increased from 30- 40% to 70% and gave better result in alkaline solution.

난연성 FREP에 의한 철근콘크리트 보의 전단보강 성능평가

강기연,최기선,한상환,유영찬 대한건축학회 2003 대한건축학회 학술발표대회 논문집 - 계획계/구조계 Vol.23 No.2(구조계)

The purpose of this study is to evaluate the shear strengthening effects of the iFREP(incombustible Fiber Reinforced Epoxy Panel) to the reinforced concrete members and to provide the basic design recommendation for shear strengthening. The main variable were the thickness of iFREP, the amount of stirrup and the type of strengthening. Thirteen specimens were tested under static monotonic loading. From the test results, it was shown that the failure mode of RC beams which are strengthened by iFREP was governed by the delamination of iFREP. The shear capacity of beams strengthened by iFREP can be determined as the summation of the shear strengths provided by concrete, stirrup, and iFREP The shear strength by iFREP should be calculated based on the effective strain of iFREP. Also, the shear strengthening effects of specimen with two-side bonded iFREP is similar to those of specimen with three-side bonded iFREP (U-TYPE).

유기산 완충용액의 포화도가 상아질의 탈회에 미치는 영향

강혜실,이찬영 大韓齒科保存學會 2004 Restorative Dentistry & Endodontics Vol.29 No.5

The purpose of this study is to compare and to evaluate the effects of the degree of saturation on the progression of artificial root caries lesion. A total of 8 human premolars without any defects and cracks selected and the cementum were removed and the teeth were cleaned with ultrasonic device and pumice without fluoride. Each tooth was sectioned into 6 pieces and they were ground with #800 sandpaper until they had a thickness of 200 ㎛. Specimens were applied with nail vanish except for the 2-3 mm window area after application of bonding agent. Under the constant pH, the specimens were divided into 6 groups (degree of saturation: 0.1415, 0.1503, 0.1597, 0.1676, 0.1771. 0.1977). Each group was immersed in acid buffer solution for 1, 2, 3, 5 days under controlled temperature (25℃) and imbibed in water and examined using the polarizing microscope. The results were as follows 1. Although the degree of saturation of demineralization solution decreased, the depth of penetration in the dentin was constant. 2. Erosion was observed on the surface of all the teeth in the group Ⅰ, Ⅱ. In the group Ⅲ, Ⅳ, Ⅴ, surfaces were not changed. The teeth in the group Ⅵ showed the more mineralized surface but not the shape of the dentinal tubules distinctively. 3. In all groups, the lesion progressed rapidly at the first day of the experiment, but increased gradually as time elapsed.

앞작물 재배와 질소 시비량의 차이에 따른 이탈리언라이그라스의 청예 수량

강영길,조남기,고영우,강민수,김용찬 濟州大學校 亞熱帶農業硏究所 1998 亞熱帶農業硏究 Vol.15 No.-

앞작물 재배와 질소시비량이 이탈리언라이그라스의 건물수량에 미치는 영향을 구명하기 위해 1997년 제주에서 콩(백운콩, 남해콩, 소백나물콩), 녹두(금성녹두, 남평녹두), 팥(충주팥), 동부(제주재래), 수수류(Pioneer 931, Pioneer 988). 옥수수(Pioneer 3525)를 기준시비하에서 재배한 후, 질소 0, 40, 80kg/ha 시용하여 1997-1998년에 재배했던 이탈리언라이그라스의 포장 건물수량, 건물율 등을 조사한 결과를 요약하면 다음과 같다. 초장, 건물수량, 건물율은 모두 앞작물재배에 의하여 유의한 영향을 받지 않았고 앞작물과 질소시비량간의 상호작용도 유의하지 않았다. 초장과 건물중은 질소시비량의 차이에 따른 큰 차이가 있었으나 건물율은 질소시비량의 차이에 빠른 차이가 거의 없었다. 초장과 건물중은 질소시비량이 0, 40, 80kg/ha에서 각각 99.5. 118.1, 120.1cm와 5.77, 7.23, 7.70ton/ha이었다. 질소이용효율은 질소 40kg/ha 시용구에서 180.8kg이었던 것이 80kg/ha 사용구에서 96.3kg로 줄어들었다. 건물수량과 질소이용효율을 고려할 때 늦가을에 파종한 이탈리언라이그라스의 적정 질소시비량은 약 80kg/ha으로 판단된다. After soybean (3 cu1tivars), mungbean (2 cultivars), cowpea, adzuki bean, maize, sorghum, sorghum × sudangrass hybrid, and Japanese millet were harvested for forage in 1997. Italian ryegrass was grown at three N rates (0, 40, and 80kg/ha) at Cheju in a 1997-1998 crop season to evaluate the effects of previous cropping and N rate on the dry matter yield of Italian ryegrass. Plant height, dry matter yield and dry matter content were not influenced by the previous cropping. There was no significant interaction between previous cropping and N rate for the three traits. Plant height and dry matter yield were significantly affected by N rate but dry matter content was not. Averaged across the previous croppings, plant heights and dry matter yields at 0, 40, and 80kg N/ha were 99.5, 118.1, and 120.1 cm and 5.77, 7 23, and 7.70 t/ha, respectively. Nitrogen use efficiency decreased from 180.8 to 96.3 kg dry matter per kg N applied as N was increased from 40 to 80 kg/ha. The optimum N rate for Italian ryegrass planted in late fall at Cheju appeared about 80kg/ha in terms of dry matter yield and N use efficiency.