• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.209-212
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• 2008

Corrugated steel-concrete composite deck with I-beam welded is lighter and has higher load carrying capacity than RC slabs due to an I-beam embedded in the corrugated deck. The methods suggested from ACI and design standard of roadway bridge are used to evaluate effective moment inertia of RC structures. This paper presents evaluation and application of effective moment inertia for corrugated steel-concrete composite deck with I-beam welded by using the methods suggested from design standard of roadway bridge, ACI and CEB-FIP MC-90. In order to evaluate effective moment inertia, a series of flexural experiments were carried out. Five beams were built and the parameters considered in the experiments were studs, shape of the sections and connections of the beams. By using the aforementioned methods, effective moments of inertia was calculated and they were compared with the experimental results. As a result, The method suggested from CEB-FIP MC-90 yielded more satisfactory agreement than that from ACI. It was found that the beam has studs showed high load-carrying capacity and high effective moment of inertia.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2015.11a
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• pp.341-344
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• 2015

본 논문에서는 소규모 공간을 규정하였다. 광의의 소규모 공간이란 바닥 면적이 $300m^2$ 미만으로서 소방관련법 상 소화설비 설치대상에서 제외되는 공간에 해당한다. 또한 협의의 개념으로 소방관련법 상 소화설비 설치대상에 해당하나 바닥 면적이 $300m^2$ 미만 중에 소화설비 설치가 제외되는 공간과 피트공간과 그 밖의 소방관련법 상 소화설비 설치대상에 포함되지 아니하는 주방을 의미한다. 소규모 공간이지만 사용 용도가 창고 등과 겸용으로 사용되어 화재하중을 예상하기 어려우며 소화설비가 요구되는 공간이다. 본 연구는 다양한 화재원인 중에 전기화재에 관한 것으로 전기설비의 안전성능 기준이 강화되고 제품의 질적 수준이 향상됨에 따라 발화요인별 화재 발생률이 다소 둔화되고 있으나 전기화재는 여전히 화재사고의 상당한 부분을 차지하고 있는 실정으로 소규모에서 발생할 수 있는 화재를 대상으로 하여 구획된 소공간유형의 EPS실에서 케이블 등의 가연성물질에 대한 화재위험성을 시뮬레이션 분석을 통하여 산정하였다.

• Proceedings of the Korea Information Processing Society Conference
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• 2013.05a
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• pp.223-225
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• 2013

어미로부터 생후 21일령 또는 28일령에 젖을 때는 어린 자돈들은 면역력이 약하여 통상 폐사율이 30~40%까지 치솟는 등 자돈 관리가 국내 양돈 농가의 가장 큰 문제 중 하나로 인식되고 있다. 본 논문에서는 이러한 양돈 농가의 문제를 해결하기 위하여 자돈사에 비디오 카메라를 설치하고 획득된 영상 정보를 이용하여 자돈들을 관리하는 시스템을 제안한다. 특히 제안된 시스템은 실시간으로 유입되는 영상 스트림 데이터로부터 움직임 여부를 신속히 판단하고, 움직임이 없는 경우(수면 또는 휴식)에 바닥면적 중 자돈들이 차지하지 않은 부분의 면적을 추출하여 수면 또는 휴식 중 자돈들의 밀집 여부를 판단한다. 즉, 카메라를 이용하여 과도하게 밀집된 경우 온도를 올려주고 반대의 경우 온도를 낮춰주는 온도제어 시스템을 설계할 수 있다. 실제, 경상남도 함양군의 한 돼지 농장에 비디오 센서 기반의 실험 환경을 구축하고 자돈사 감시 데이터 셋을 취득하였고, 이를 이용하여 제안된 자돈사 관리 시스템의 프로토타입을 개발하였다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.49-52
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• 2008

The tensile and bond performance of GFRP rebar are different from those of conventional steel reinforcement. It requires some studies on concrete members reinforced with GFRP reinforcing bars to apply it to concrete structures. GFRP has some advantages such as high specific strength, low weight, non-corrosive nature, and disadvantage of larger deflection due to the lower modulus of elasticity than that of steel. Bridge deck is a preferred structure to apply FRP rebars due to the increase of flexural capacity by arching action. This paper focuses on the behavior of concrete bridge deck reinforced with newly developed GFRP rebar. A total of three real size bridge deck specimens were made and tested. Main variable was reinforcement ratio of GFRP rebar. Static test was performed with the load of DB-24 level until failure. Test results were compared and analyzed with ultimate load, deflection behavior.

• Proceedings of the Korea Information Processing Society Conference
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• 2023.05a
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• pp.18-19
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• 2023

최근 상품의 특성을 고려하지 않은 박스 크기 선택과 박스 공간 내 비효율적인 상품 배치로 인하여 박스의 파손 문제가 지속적으로 제기되고 있다. 이는 적재하고자 하는 상품의 특성을 고려하지 않고 상품을 대략적으로 배치하기 때문이다. 따라서 본 논문에서는 면적과 무게와 같은 상품의 특성을 고려한 상품 배치 최적화 알고리즘을 제안하여 공간 배치의 비효율성 문제를 최소화하고자 한다. 제안한 상품 배치 최적화 알고리즘은 검색 트리 (search tree)와 상품 특성 기반 평가 함수(evaluation function)로 구성되어 있다. 상품 특성 기반 평가 함수는 면적, 무게 및 바닥에 닿는 면적을 고려하여 설계되었다.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.2
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• pp.37-43
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• 2014

In this paper, we present the effect of forward current gain on emitter area in NPN transistors are used widely in the almost linear integrated circuits and integrated injection logic. Relations between forward current gain and emitter area were conformed with the simulation with examined calculation and experiments. At the same emitter length, as junction depth is increased, common emitter current gain is decreased. Ratio of Emitter bottom area comparing to side area increases, the emitter current gain is increased. The theory and simulation results were fitted in with the experimental data very well.

• Journal of the Korean Institute of Gas
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• v.15 no.3
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• pp.26-30
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• 2011

Instantaneous water heater being not properly installed and not adequately maintained may produce fatal accidents due to carbon monoxide poisoning and suffocation. Insufficient supply of air into the gas appliance for complete burning of the fuel or blocking the outlet of the combustion gas could be a cause to increase carbon monoxide concentration in the exhaust gas of the gas appliance. In this work, the experiments are done with a collected instantaneous water heater using in domestic and the concentration of oxygen near the gas appliance and carbon monoxide in exhaust gas are observed to investigate the risk of instantaneous water heater. The concentration of oxygen near the gas appliance is reduced until 17.7% for the ratio of the ventilation area and floor area being 3.5%. If the outlet of combustion gas is blocked, the carbon monoxide concentration is steeply increasing more than 4,000ppm. Therefore, periodic checking the outlet of combustion gas is more important than vent area to reduce the risk of carbon monoxide poisoning.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.28 no.5B
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• pp.535-546
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• 2008

Urbanization results in increased runoff volume and flowrate and shortening in time of concentration, which may cause frequent flooding downstream. The retardation structures are used to eliminate adverse downstream effects of urban stormwater runoff. There are various types of flow retardation measures include detention basin, retention basin, and infiltration basin. In this study, to present a rough standard about location of detention pond for attenuating peak flow of urban area, the runoff reduction effect is analyzed at outlet point when detention pond is located to upstream drainage than outlet. The runoff reduction effects are analyzed under the three assumed basins. These basins have longitudinal shape (SF = 0. 204), concentration shape (SF = 0. 782), and middle shape (SF = 0.567). Numerous variables in connection with the storage effect of detention pond and the runoff reduction effects are analyzed by changing the location of detention pond. To analyze runoff reduction effect by location of single detention pond, Dimensionless Upstream Area Ratio (DUAR) is changed to 20%, 40%, 60%, and 80% according to the basin shape. In case of multiple detention pond, DUAR is changed to 60%, 80%, 100%, 120%, and 140% only under the middle shape basin (SF = 0.567). Related figures and regression equations to determine the location of detention pond are obtained from above analysis of two cases in this study. These results can be used to determine the location of appropriate detention pond corresponding to the any runoff reduction such as storage ratio and peak flow ratio in urban watershed.

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.28 no.1
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• pp.25-30
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• 1999

최근 고도의 경제성장과 함께 유통구조의 선진화로 대형화, 하역 및 적재, 운반기계의 자동화를 도입하므로써 생산 또는 보관제품의 품질 보존, 작업 인원의 최소화 및 교통체중에 대한 적절한 대응으로 고품격의 물류 서비스를 할 수 있게 되었다. 특히, 생산 또는 보관제품의 품질 보존을 위해서는 물류 창고 내의 물류 특성에 따른 실내 공조환경 즉, 적정한 온 습도 및 기류를 유지하도록 공조설비를 계획하여야 하는데 층고가 높고 바닥면적이 넓은 대형 물류센터 즉, 산업용 대공간에 대한 공조설비는 층고 높이로 적재된 장애물을 극복하고 취출되는 기류가 실내 전체에 골고루 확산 및 순환 될 수 있도록 적정한 공조방식을 선정하여야 한다. 따라서 본 계획에서는 주로 N-스포츠사의 이천 물류센터 공조방식의 설계 사례를 들어 산업용 대공간에 대한 공조계획 개선 방안을 소개 하고자 한다.

• Resources Recycling
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• v.19 no.1
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• pp.33-39
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• 2010

The spheric sintered body with $6{\pm}2mm$ diameter was manufactured in a rotary kiln at $1125^{\circ}C$/15 min using green body formed by pelletizing the batch powder composing of coal bottom ash produced from power plant and dredged soil by 70:30, wt%. And the physical properties of sintered body (BD) were analyzed to confirm the possibility for applying to an absorbent to restore a contaminated soil. The sintered body had a giant pore above 100 ${\mu}m$ and a fine pore below 10 ${\mu}m$, and bulk density was 1.4. Also its specific surface area, porosity and void proportion were $12.0m^2/g$, 30.1% and 38.2% respectively. The crushed body (BD-C), produced by crushing a BD specimen into an irregular shape with a aspect ratio of about 2, was similar to BD specimen at bulk density and pore size distribution. But it had superior values of specific surface area, porosity and void proportion compared with BD specimen owing to a decreased apparent volume due to conversion of closed pore existed at interior of BD to open pore during a crushing process. The IEP of sintered body occurred at about pH=5, so the optimum pH condition of reacting aqueous solution could be known before bonding a microbe to the sintered body. Hence, the optimum void proportion and porosity of an absorbent can be obtained by appropriate mixing a BD with BD-C from the base data calculated in this study.