• 한국물환경학회지
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• 제26권6호
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• pp.1008-1015
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• 2010

Discharged pollution load is varied as rainfall changes in the area with combined sewer system. Changes in discharged pollution load are directly related with those of sewer transfer flow. Therefore, it is important to identify the pattern of sewer transfer flow for the analysis of changes in discharged pollution load. This study reviewed the type of distribution of sewer transfer flow for 17 sewage treatment plants and developed simple formular to estimate sewer transfer flow as rainfall changes. 11 facilities showed to have some relation with rainfall in the change of sewer transfer flow but 6 facilities to have no relation. Relationships between rainfall amount and sewer transfer flow showed that 6 facilities out of 11 had relatively strong relationships above R2=0.5, which were considered to be affected directly by rainfall changes. The formular which explain the relationship between rainfall and sewer transfer flow can be applied in the analysis of rainfall effects on discharged pollution load, therefore, the more appropriate evaluation will be done.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.863-868
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• 2008

In accordance with the guidelines on the balcony structure changes in December 2005, most of tenants were moving into apartment housing, expand the balcony, but some large deviation between the price construction costs set of cases, due to overuse and the cause of the dispute, and the housing law amended in 2007 due to price cap system is implemented, the cost of expansion the balcony overdose pointed out that there is set to boost the sale price has been raised. These issues in order to improve the government in January 2008, the "Note costs by the balcony expansion" suggested guidelines to protect the rights of tenants and wants to promote the settlement of the sale price cap system. This study calculated the "Note costs by the balcony expansion" window system based on double or single, high performance insulation window system of the quantitative performance analysis of each type window that purpose.

• Advances in concrete construction
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• 제10권1호
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• pp.49-59
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• 2020

Precast concrete elements in accelerated bridge construction (ABC) extends from superstructure to substructure, precast pile foundation has proven a benefit for regions with fragile ecological environment and adverse geological condition. There is still a lack of knowledge of the seismic behavior and performance of the precast pile foundation. In this study, a 1/8 scaled model of precast pile foundation with elevated cap is fabricated for quasi-static test. The failure mechanism and responses of the precast pile-soil interaction system are analyzed. It is shown that damage occurs primarily in precast pile-soil interaction system and the bridge pier keeps elastic state because of its relatively large cross-section designed for railways. The vulnerable part of the precast pile with elevated cap is located at the embedded section, but no plastic hinge forms along the pile depth under cyclic loading. Hysteretic curves show no significant strength degradation but obvious stiffness degradation throughout the loading process. The energy dissipation capacity of the precast pile-soil interaction system is discussed by using index of the equivalent viscous damping ratio. It can be found that the energy dissipation capacity decreases with the increase of loading displacement due to the unyielding pile reinforcements and potential pile uplift. It is expected to promote the use of precast pile foundation in accelerated bridge construction (ABC) of railways designed in seismic regions.

• 환경위생공학
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• 제22권3호
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• pp.13-26
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• 2007

Changes in the characteristics of dissolved organic matter was studied at selected stations in the Nakdong river basin using physical and chemical methods. Characteristics of dissolved organic matters were analysed and assessed. Production of disinfection byproducts were also investigated. 1. Result of relatedness study among each items of analyses showed that relatedness on BOD values were highest with cattle excrement treatment facilities where there is no synthetic organic materials and relatedness on $COD_{Mn}$ were highest at the mainstream Nakdong river. In case of $COD_{Cr}$ (which has more oxidative power than $COD_{Mn}$), the values were higher in the sidestreams indicating the higher content of recalcitrant compounds. The relatedness values for the $UV_{254}$ also showed higher values in the sidestreams and treatment facilities than mainstream indicating the presence of organic aromatic compounds. 2. Ratio of DOC on total organic carbon were higher in the mainstream which is attributable to the influent particulate organic materials produced by agricultural activities. The values were 10-15% higher in the mainstream compared with sidestreams. 3. Result of biodegradability test indicate that concentrations of recalcitrant DOC were higher in the sidestreams than in the mainstream. The values of recalcitrant DOC were higher with the forest stream indicating the effect of soil oriented humic substances. 4. Result of THM production test carried out at 10 stations in the Nakdong river show that $CHCl_3$ was detected with the highest value and the value was highest at Waekwan station.

• 한국항행학회논문지
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• 제16권3호
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• pp.504-509
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• 2012

IPTV 환경에서 복수개의 제한 수신 시스템 CAS(Condition Access System)를 안전하게 다운로드 하여 실행 하도록 하고, IPTV 사업자간에 단말의 호환성 및 이동성을 제공하기 위한 국내 표준화 규격인 iCAS(Interchangeable CAS)는 Real-Time Streaming 방송 보호를 위한 CAS 교환에 대해서만 정의하고 있다. 하지만, IPTV 양방향 통신 환경의 장점을 활용한 다양한 방송 서비스의 콘텐츠 보호 요구사항을 충족시키기에 CAS는 한계가 있으며, CAS가 가지는 한계를 보완하기 위해서 DRM 보호기술이 요구된다. 실시간 방송 서비스 또는 실시간 VOD 서비스의 콘텐츠는 CAS 기술로 보호가 가능하게 하고, PVR 또는 다운로드 VOD 서비스, 다운로드 콘텐츠의 공유 등과 같은 서비스는 DRM 기술로 보호가 가능하므로 CAS와 DRM 상호 보완을 통해 다양한 서비스에 대응하여 유연한 IPTV 단말 서비스 환경을 구축할 수 있다. 따라서, 본 논문에서는 iCAS 표준화 규격에 준하는 DRM 확장 적용 방안을 연구하고, 상용화에서 iCAS/DRM이 적용된 시스템 구성을 제안한다.

• 한국HCI학회논문지
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• 제12권4호
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• pp.75-80
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• 2017

최근 인지과학의 활발한 연구와 기술의 발달로 인해 사회과학분야에서 정신생리학적 연구를 통한 뇌의 다양한 측정과 정교한 분석 기법이 개발 되었다. 그러나 뇌파를 이용한 뉴미디어활용에 관한 연구는 장비들을 장착하는 과정에서의 한계점으로 인해 진행되지 못하였다. 이러한 문제를 극복하고자, 가상현실장비를 착용한 상태에서도 전 영역의 뇌파측정이 가능한 캡을 디자인하고 활용방법을 제안한다.

• Coupled systems mechanics
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• 제1권1호
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• pp.1-7
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• 2012

The problem of laterally loaded piles is particularly a complex soil-structure interaction problem. The flexural stresses developed due to the combined action of axial load and bending moment must be evaluated in a realistic and rational manner for safe and economical design of pile foundation. The paper reports the finite element analysis of pile groups. For this purpose simplified models along the lines similar to that suggested by Desai et al. (1981) are used for idealizing various elements of the foundation system. The pile is idealized one dimensional beam element, pile cap as two dimensional plate element and the soil as independent closely spaced linearly elastic springs. The analysis takes into consideration the effect of interaction between pile cap and soil underlying it. The pile group is considered to have been embedded in cohesive soil. The parametric study is carried out to examine the effect of pile spacing, pile diameter, number of piles and arrangement of pile on the responses of pile group. The responses considered include the displacement at top of pile group and bending moment in piles. The results obtained using the simplified approach of the F.E. analysis are further compared with the results of the complete 3-D F.E. analysis published earlier and fair agreement is observed in the either result.

• Earthquakes and Structures
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• 제20권1호
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• pp.87-96
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• 2021

Ground motions recorded in near-fault sites, where the rupture propagates toward the site, are significantly different from those observed in far-fault regions. In this research, finite element modeling is used to investigate the effect of pile cap stiffness on the seismic response of soil-pile-structure systems under near-fault ground motions. The Von Wolffersdorff hypoplastic model with the intergranular strain concept is applied for modeling of granular soil (sand) and the behavior of structure is considered to be non-linear. Eight fault-normal near-field ground motion records, recorded on rock, are applied to the model. The numerical method developed is verified by comparing the results with an experimental test (shaking table test) for a soil-pile-structure system. The results, obtained from finite element modeling under near-fault ground motions, show that when the value of cap stiffness increases, the drift ratio of the structure decreases, whereas the pile relative displacement increases. Also, the residual deformations in the piles are due to the non-linear behavior of soil around the piles.

• 한국강구조학회 논문집
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• 제27권2호
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• pp.155-167
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• 2015

춤이 깊은 데크를 6m 이상 장스팬 바닥에 사용할 경우에는 시공단계에서 데크의 발생하는 많은 처짐에 의한 작업자 및 시공안전을 고려하여 가설지주를 사용하는 것이 통상적이었다. 그러나 시공안전은 확보하였지만, 가설지주의 설치는 작업자의 통로제한, 공간의 협소, 능률의 감소 등으로 시공성의 문제가 발생한, 이는 춤이 깊은 데크는 상부 개방인 골 형태로 인한 벌어짐이나 박판으로 인한 웨브크리플링, 데크의 상부 플렌지의 국부처짐 등의 불안정성 문제가 발생할 수 있고, 이로 인해 개방형 데크의 횡-비틀림 좌굴과 같은 구조적 문제가 발생할 수 있다. 본 연구는 시공단계 동안 작용하중에 대한 춤이 깊은 데크의 제한 처짐 값을 제안하며, 장스팬의 구조안정성을 확보하고자 춤이 깊은 데크의 단부에 캡플레이트로 보강한 후 시공단계하중을 모래 재하 방법으로 실물실험 제작하여 실험을 실험하였다. 실험결과 개선안 캡플레이트 적용 유무에 따라 발생 처짐량이 최대 1/5 감소하였고, 모든 특히 단부를 연속화한 실험체의 경우, 처짐이 국내 규준과 제안 처짐 값(L/180, 30mm)을 만족하였다.

• 한국콘텐츠학회논문지
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• 제21권12호
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• pp.296-301
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• 2021

본 연구는 차세대 예경보 플랫폼과 지상파 UHD 방송의 재난경보 부가데이터 서비스를 연동한 표준화된 멀티미디어 재난경보방송의 실증 시험을 다룬 연구이다. 실증 시험에 사용된 차세대 예경보 플랫폼은 CAP 기반의 TTA 표준화 규격을 준수하고, UHD 재난경보 부가데이터 서비스는 AEAT 규격을 준수하도록 구성하였다. 실증 시험은 2021년 3월 제주도에서 지상파 UHD 방송 송수신을 포함하여 실시되었다. 실험 결과 표준화된 CAP 재난경보메시지가 발령되어 방송사에 전달되면 UHD 재난경보 부가데이터 메시지인 AEAT로 자동 변환되어 송출되도록 시스템을 구축하였다. 수신부는 재난경보 데이터 수신이 가능한 셋탑과 TV를 HDMI 케이블로 연결하여 구성하였다. 재난이 발령되면 셋탑은 TV방송 화면위에 AEAT 메시지가 재난 우선순위와 발령 지역에 맞춤형으로 표출하였다. 또한 수신 메시지는 5개국어 중에서 사용자 설정에 맞는 언어로 표출되고. 이미지와 경보음과 같은 부가 멀티미디어 기능도 연계할 수 있었다. 특히 재난경보 발령 후 3초 이내에 수신기 메시지가 표출되어 신속한 재난경보 전달이 가능함을 확인할 수 있었다.