• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.06a
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• pp.256-257
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• 2011

해상용 등부표에 사용중인 태양전지시스템의 적절한 용량 설계를 통하여, 오동작 유발 및 과잉투자 손실을 줄이기 위해, 등명기의 실부하를 산정하였다. 향후 용량 설계를 위한 기초자료를 이용될 수 있다.

• Monthly Korean Chicken
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• v.6 no.1 s.55
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• pp.2-7
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• 2000

중국산 가금육, 포장의무화 수입허용 건의 - 농림부 축산물 위생관리 업무 검역원에 위임 - 2000년도 닭계열화사업 2개소 지원 - 회장단, 농림부에 신년인사 다녀와 - 환기 관리 I - 생산성 향상을 위한 사육환경개선 세미나 실시 - 미국 닭고기 생산증가율 높아 - 태국, EU 수출을 위한 산업체질 개선 - 일본, 유전자조작 곡물 기피 증가 - 볏짚 자리깃, 주의해서 사용해야 - 미, 공급과잉으로 곡물가 하락 전망 - 도계처리 방법에 따라 영양가 달라져 - 종란의 살모넬라 오염 방지를 위한 소독 처리

• Journal of the Korean Data and Information Science Society
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• v.26 no.2
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• pp.387-397
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• 2015

In this paper, the determinants of the number of job changes in the SMEs (small and medium enterprises) youth-intern project is analysed, utilizing SMEs youth-intern DB and employment insurance DB. Since the number of job changes are count data which take integer values other than negative values, general linear regression analysis becomes inappropriate. Therefore, four models such as Poisson regression model, zero inflated Poisson regression model, negative binomial regression model and zero inflated negative binomial regression model are tried to fit count data. A zero inflated negative binomial regression model is selected to be the best model. Major results are the followings. First, the number of job changes is shown to be significantly smaller in the treatment group than in the control group. Second, the number of job changes turns out to be significantly smaller in the young-age group than in the old-age group. Third, it is also shown that the number of job changes of man is significantly greater than that of woman. Lastly, the number of job changes in the bigger firm is shown to be significantly less than that of the smaller firm.

• Journal of the Korean Institute of Gas
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• v.21 no.3
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• pp.53-60
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• 2017

Various researches have been conducted for the reduction of NOx at the combustion furnace and exhaust gas recirculation method is commonly used technology for NOx reduction. The present research adopted coanda nozzles at the outside pipes of furnace to entrain the exhaust gas for the exhaust gas recirculation and the mixed gas was ejected to the tangential direction to cause the swirl flow in the furnace. The combustion flow characteristics in the exhaust gas recirculation burner with coanda nozzle has been elucidated by analyzing the swirl flow streamlines, temepraure and reaction rate distribution in the furnace. The exhaust gas entrained flow rate has been investigated by changing the excess air factor and coanda nozzle gap and the exhaust gas entrained flow rate increased with the increase of excess air factor and it decreased with the increase of coanda nozzle gap. The mean temperature at the exit plane of exhaust gas decreased with the excess air factor and it was little affected by the increase of coanda nozzle gap. The NOx mass fraction at the exhaust gas exit plane remarkably decreased with the excess air factor and it was also little affected by the increase of coanda nozzle gap.

• Journal of the Korean Geotechnical Society
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• v.23 no.3
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• pp.25-40
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• 2007

Excessive earth pressure is one of the major mechanical factors in the deformation and damage of Cut-and-Cover Tunnel lining in shallow tunnels and portals of mountain tunnels (Kim, 2000). Excessive earth pressure may be attributed to insufficient compaction and consolidation of backfill material due to self-weight, precipitation and vibration caused by traffic (Komiya et al., 2000; Taylor et al., 1984; Yoo, 1997). Even though there were a lot of tests performed to determine the earth pressure acting on the tunnel lining, unfortunately there were almost no case histories of studies performed to determine remedial measures that reduce differential settlement and excessive earth pressure. In this study the installation of geotextile mat was selected to reduce the differential settlement and excessive earth pressure acting on the cut-and-cover tunnel lining. In order to determine settlement and earth pressure reduction effect (reinforcement effect) of geotextile mat reinforcement, laboratory tunnel model tests were performed. This study was limited to the modeling of rigid circular cut-and-cover tunnel constructed at a depth of $1.0D\sim1.5D$ in loose sandy ground and subjected to a vibration frequency of 100 Hz. Model tests with varying soil cover, mat reinforcement scheme and slope roughness were performed to determine the most effective mat reinforcement scheme. Slope roughness was adjusted by attaching sandpaper #100, #400 and acetate on the cut slope surface. Mat reinforcement effect of each mat reinforcement scheme were presented by the comparison of earth pressure obtained from the unreinforced and mat reinforced model tests. Soil settlement reduction was analyzed and presented using the Picture Analysis Method (Park, 2003).

• Journal of the Korean Geotechnical Society
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• v.22 no.5
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• pp.59-67
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• 2006

The centrifuge and 1-g shaking table tests were performed simultaneously to compare the dynamic behaviors of loose sands of the same geotechnical properties. The prototype soils were 10 m thick liquefiable loose sands. The geometric scaling factors were 20 for 1-g and 40 for centrifuge tests. The excess pore pressure, surface settlement, and acceleration in the soil were measured at the same locations in the 1-g and centrifuge tests. The total excess pore pressure from development to dissipation was measured. In the centrifuge test, viscous fluid was used as the pore water to eliminate the time scaling difference between dynamic time and dissipation time. In the 1-g tests, the steady state concept was applied to determine the unit weight of the model soil, and two different time scaling factors were applied for the dynamic time and the dissipation time. It is concluded that the 1-g tests can simulate the excess pore pressure of the prototype soil if the permeability of the model soil is small enough to prevent dissipation of excess pore pressure during shaking and the dissipation time scaling factor is properly determined.

• Applied Chemistry for Engineering
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• v.20 no.4
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• pp.363-369
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• 2009

High oil price and biodiesel expansion lead the surplus of glycerol in the market. Glycerol has been used as a raw material itself at petroleum chemistry, paint, tobacco, household products and cosmetics in the conventional market. Recently, many research to find new applications of glycerol as a low-cost feedstock for functional derivatives have led to the introduction of a number of selective processes for converting glycerol into commercially value-added products. The recent studies on the development of new value-added glycerol derivatives will be reviewed.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10e
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• pp.127-129
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• 2002

NP Forum에서는 다양한 밴더의 네트워크 프로세서와 스위치 패브릭간에 물리적 인터페이스를 제공하기 위해 CSIX-L1(Common Switch Interface-Level 1 )인터페이스를 표준화하였다. IBM 네트워크 프로세서는 MPLS 및 VPN, VLAN, Security, Ipv6와 같은 다양한 어플리케이션과 TBI. SMII CMII. POS bus등 다양한 가입자 인터페이스를 지원하며, L2 기 반에서 2.5Gbps 이상의 패킷 처리를 수행하기 때문에 많은 시스템에 사용된다. 그러나 IBM네트워크 프로세서는 스위치 인터페이스로 DASL인터페이스를 사용한다. 따라서 DASL인 터페이스와 CSIX-L1 인터페이스를 정합하기 위해서는 IBM UDASL칩을 이용해 DASL인 터페이스를 UTOPIA-L3인터페이스로 변환해야 하며, 이것을 다시 CSIX-L1인터페이스로 변환해야 한다. 따라서 본 논문에서는 UTOPIA-L3인터페이스 패킷과 CSIX-L1인터페이스 프레임을 상호 변환하는 모듈을 설계하였으며, 32비트 데이터 버스와 최대 125MHz로클록을 사용해 최대 4Gbps의 패킷처리를 제공하도록 구현하였다. 또한 스위치 패브릭의 특정 포트에서 과잉 트래픽 전달로 인해 발생할 수 있는 블로킹을 방지하기 위해 네트워크 프로세서에게 3개의 Priority／최대 64개 포트수의 VOQ(Virtual Output Queue)를 제공하는 기법에 대해서 기술한다.

• Journal of the Korean Geotechnical Society
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• v.17 no.2
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• pp.95-101
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• 2001

연약한 점토 지반에 안벽을 축조하고 매립하는 경우, 안벽의 기초로서 케이슨 기초공법이 종종 쓰이고 있다. 케이슨 기초는 안벽의 연직 하중을 지지층에 전달할 뿐만 아니라, 매립하중에 의한 연약 점토의 횡방향 소성 유동에 대하여는 매우 효과적인 공법으로 호안공사에서 그 사용 빈도가 증가하고 있는 추세이다. 반면 매립하중에 의해 점토지반에서 장기간에 걸쳐 발생하는 압밀침하에 대해서는 아무런 역할을 하지 못하는 단점이 있다. 따라서 본 연구에서는 기존 케이슨 기초의 배면에 다수의 강관 배수공을 설치함으로써 과잉간극수압의 횡방향 소산을 촉진시켜 압밀 시간을 단축시키는 \"매립측 연약점토 압밀촉진 케이슨 기초공법\"을 제안하였다. 이 새로운 케이슨 공법의 압밀촉진 효과를 분석하기 위하여 2차원 압밀방정식의 해석해를 유도하였다. 연구결과, 등방성 점토에서 압밀촉진 케이슨 사용시 ξ=0.1인 단면에서 평균압밀도 50%, 90%에 이르는 시간이 기존 케이슨을 사용한 것에 비해 각각 약 7배, 3.5배 단축되는 것으로 나타났다. 것으로 나타났다.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.12
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• pp.2287-2297
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• 1992

The Formulation of a new Hermite straight beam element to eliminate the shear locking is presented. All the kinematic variables in Timoshenko beam are reinterpreted by the consideration of equilibrium equations together. It shows that when the modified transverse displacement field is used the Timoshenko beam looks apparently the same as the Euler beam. The element is formulated for the modified transverse displacement field to have the same interpolation scheme as that in the Hermite element. Transformation Matrix which relates a modified nodal vector with nonmodified one is also introduced to deal with general boundary conditions. Several examples are demonstrated and discussed for the purpose of verification of the concepts employed. The solutions obtained reveal that the element describes of the beam quite correctly, showing no locking and that it is also applicable to the analysis of both thin and thick beams.