• Journal of Animal Environmental Science
• /
• v.13 no.3
• /
• pp.195-200
• /
• 2007

Management of odors is essential to swine industry in the Republic of Korea. This study was conducted to evaluate the odor removal efficiency of biofilter ducting systems. Rice straw and auto clave concrete(ALC) were used as filter medium. The ventilation fans(5 units, diameter: 500 mm) at the side wall of a growing pig housing were connected to a biofilter using a duct. The size of a biofilter is $2.5{\times}2{\times}1.2(W{\times}L{\times}H)$. The air velocities at the 300 mm above rice straw and ALC were 0.77 and 0.56 m/s, respectively. Ammonia concentration at the outlet of rice straw and ALC media were 2 and 3 ppm, respectively. Dust concentrations were also measured. The dust concentrations of rice straw and ALC were 93, $32\;mg/m^3$, respectively. There was no significant difference between filter mediums in terms of carbon dioxide concentrations(rice straw: 320, ALC: 270 mg/l). The concentration of hydrogen sulfide was stable over the experimentation. The actual concentrations of hydrogen sulfide were 4, 3 and 3 ppm at the days of 7, 21 and 36, respectively. These results suggest that biofilter ducting systems may remove odors from pig house effectively.

• Proceedings of the KAIS Fall Conference
• /
• 2011.12a
• /
• pp.262-265
• /
• 2011

본 연구는 탈진 기류 분사 시스템의 최적화 설계에 관한 기초 연구의 일환으로 전산유체역학(CFD)을 이용하여 일반 블로우 튜브와 단순 벤츄리 조합의 충격 기류(Pulse air jet) 방식의 탈진 장치에 대한 탈진 성능과 벤츄리 입구에 기류 유도용 구조물을 설치한 경우의 탈진 성능을 비교하였다. 각 Case별로 벤츄리 내부로 유입되는 탈진 공기량을 예측한 결과, case 2의 벤츄리 형상 개조시 case 1 보다 벤츄리로 유입되는 탈진 공기량이 약 20% 증폭되는 것으로 나타났다. 또한 필터백 표면에서의 탈진 기류 전달 분포를 예측한 결과, 모든 case가 필터백의 국한된 영역으로 탈진 기류가 집중됨을 알 수 있었다. 또한, case 2의 경우가 case 1보다 오히려 탈진 기류의 전달 수준이 불량함을 알 수 있다. 이는 case 2의 경우 벤츄리 입구에 기류 유도용 구조물을 설치한 것이 탈진 공기량을 증폭시키는데에는 도움이 되나, 오히려 벤츄리 내부로 유입된 탈진 기류의 직진성을 보완하여 필터백 내부에서 탈진 기류의 확장을 방해하기 때문인 것으로 판단된다.

• Journal of the Korea Convergence Society
• /
• v.7 no.6
• /
• pp.249-258
• /
• 2016

In this research, we analyzed the research and development process of small and medium enterprises, and diagnosed the problem of the research and development process of domestic small and medium enterprises, and evaluated the influence of innovative ability on the speed of research and development and corporate performance. In evaluating these effects, it is possible to grasp the direction of power generation according to the type of analysis, taking into account the meltdown factor of factors related to innovative capabilities. The main purpose of this research is to confirm the influence on the speed of research and development according to the innovative capacity and business environment and to verify the reliability and validity of the research by Klumbach alpha Was used. In this research, we analyzed how the speed of R & D affects R & D activities, it is a research aimed at the necessity of a resource-based approach to the internal capacity of a company, Have a valuable value. Based on the influence on the company, each factor is a research that analyzed the influence on R & D and financial indicators through maintaining company's development level, Research that has practical value that can base on the development of R & D capacity on corporate strategy formulation.

• Journal of the Korea Concrete Institute
• /
• v.26 no.6
• /
• pp.707-714
• /
• 2014

CFT (Concrete-Filled Tube) is a type of steel column comprised of steel tube and concrete. Steel tube holds concrete and the concrete inside tube takes charge of compressive load. This study presents structural performance of the CFT column which has 73~100 MPa high strength concrete inside. Fluidity, mechanical compression, pump pressure test in flexible pipe were conducted for understanding properties of the high strength concrete. Material properties were achieved by various experimental tests, such as slump, slump flow, air content, U-box, O-Lot, L-flow. In addition, mock-up tests were conducted to monitor concrete filling, hydration heat, compressive strength. From construction sites in Sang-am dong and University of Seo-kang, long-term behaviors could be effectively predicted in terms of ACI 209 material model considering elastic deformation, shrinkage and creep.

• Applied Chemistry for Engineering
• /
• v.7 no.1
• /
• pp.59-66
• /
• 1996

Novel chitosan beads containing a series of bisamino-terminated polyethylene glycol (Bisamino-PEG, $Jeffamine^{(R)}ED$ series) have been prepared via capillary extrusion method using an alkaline solution. The results of swelling kinetics of chitosan beads showed that as the chain length of PEG in chitosan beads increased, the swelling process of the beads proceeded slowly. In order to study the releasing kinetics quantitatively, fluorescamine was coupled to the pendant amino groups and the releasing processes were followed by UV spectra. The results revealed that the releasing process was retarded in the order of $Jeffamine^{(R)}ED$-600 < $Jeffamine^{(R)}ED$-900 < $Jeffamine^{(R)}ED$-2001 as the chain length of PEG was increased. The slow release of PEG from the beads is considered to be governed by the chain length of PEG and interpolymeric hydrogen bonding between PEG and the chitosan molecule.

• Journal of Technology Innovation
• /
• v.24 no.1
• /
• pp.1-24
• /
• 2016

This study examined 142 electronic components, video, audio, and communications equipment manufacturers (KSIC 32) out of all the SMEs that responded to the Survey on Technology of the Small and Medium Enterprises in both 2005 and 2007 and empirically analyzed how the external resources utilization and the absorptive capability affected the management and the innovation performance in two years as well as how the absorptive capability moderated these relationships. According to the results of analysis, the external resources utilization, as measured by the technology collaboration and the governments R&D subsidies, did not have a significant impact on performance whereas R&D investment showed a positive (+) influence on the sales and R&D personnel ratio, negative (-). On the other hand, the moderating effect of absorptive capability varied by measurement method and independent variables. That is, when a technology collaboration takes place, the performance improved with the increase of R&D investment but R&D personnel ration had an opposite effect. The companies whose performance improved as the government R&D subsidies increase are those with low R&D investment or high R&D personnel ratio. These results demonstrate that the SME's external resources utilization cannot replace the internal and that the absorptive capability needs to be accumulated to maximize the effectiveness of external resources utilization. Also, the technology collaboration requires SME's aggressive investment in R&D and the government R&D subsidies turn out to be more helpful for the companies that already have the R&D personnel but have been unable to develop their own technology due to insufficient funds. This study has limitations in that it was conducted within the limited industry categories and samples, but has overcome those of the existing researches by identifying causal relationships through the use of longitudinal data.

• Proceedings of the KIEE Conference
• /
• 2011.07a
• /
• pp.766-767
• /
• 2011

전력 IT 추세에 따라 IED(Intelligent Electronic Device)에서 다양한 기능이 요구되고 있으며, 따라서 이를 구현하기 위한 시스템도 복잡화되어 가고 있다. 또한 IED 내부에서에서 처리하여야 하는 데이터양이 대폭 증가하고 있으며 고속의 처리 속도를 요구하고 있기 때문에 산업용 시스템 버스의 도입 필요성이 제기되고 있다. 산업용 시스템 버스는 오랜 적용기간을 통해 그 신뢰성을 검증받았으며, 호환성이 뛰어나 H/W 플랫폼으로서의 가치가 있다. IED의 경우와 같이 다수 개의 CPU가 요구되는 시스템에서 CPU간 H/W적인 데이터 인터페이스 방식을 어떻게 선정하는지는 매우 중요하며 본 논문에서는 CompactPCI 기반의 최신 기술인 CompactPCI Plus IO와 Serial 기술에 대하여 살펴보고, IED에서 사용되는 기존의 메모리 공유방식이나 저속 시리얼 방식 대신 상기 CompactPCI 기반의 기술을 적용하는 방안에 대하여 검토해 보기로 한다.

• Journal of the Korean Institute of Gas
• /
• v.9 no.3 s.28
• /
• pp.27-31
• /
• 2005

The membrane to be applied inside of the LNG storage tank is provided with corrugations to absorb thermal contraction and expansion caused by LNG temperature and pressure changes. It is very important to measure their thermal strains under LNG temperature by analytical and experimental stress analysis of the membrane. We have developed a stress measurement system using strain gages and measured the strain during cooldown and storing the LNG. We also analyzed the measured data by comparison with the FEM data.

• Proceedings of the Korea Information Processing Society Conference
• /
• 2001.10b
• /
• pp.1435-1438
• /
• 2001

MGCP는 IETF에서 제안한 VoIP기술의 표준 프로토콜로서 특유의 단순함(Simplicity)을 이용하여 다른 프로토콜과의 연동을 용이하게 구현할 수 있도록 설계되었으며, 현재 다양한 시스템과 프로토콜로 구성되어 있는 망을 통합하기 위한 적절한 해결책으로 부각되고 있다. 본 논문에서는 MGCP기반의 AX-Gateway 시스템의 설계기법에 관하여 기술한다. MGCP기반의 AX-Gateway 시스템은 H.323과의 연동을 위하여 내부적으로 자신에게 연결된 Endpoint의 상태정보를 유지하도록 설계하였다. 이러한 구조를 통해 자신에게 전달되는 호처리 요청에 대한 유효성을 MG 차원에서 검사함으로써, Call Agent의 부하를 줄여 시스템의 안정성과 성능 향상을 기대할 수 있다. 이렇게 구현된 AX-Gateway 시스템의 성능을 측정하기 위하여 통화음질과 지연, 최대 동시 통화 사용자의 수를 측정한 결과를 나타내었다.

• Proceedings of the KIEE Conference
• /
• 2015.07a
• /
• pp.431-432
• /
• 2015

본 논문은 초고압 가스절연개폐장치의 메인 접점의 압점력에 따른 절연 특성에 대한 연구이다. 차단기 접점의 접촉이 잘 이루어지지 않는 현상이 발생하게 되면 접촉저항이 증가하여 차단기의 투입 및 개방 시에 전류에 의하여 접점에 손상이 발생한다. 그리고 차단기의 접점의 압점력이 커질수록 큰 조작력이 필요하므로 차단기의 동작에도 영향을 미치는 것은 많이 알려져 있다. 그러나 압점력과 절연 특성의 관계에 대한 연구가 미비하므로 이에 대한 연구가 필요하다. 본 연구는 초고압 가스절연개폐장치의 메인 접점의 압점력에 차이에 따른 전계를 해석하고, 고정측 접점의 쉴드 유무에 따른 절연 내력을 비교 및 분석하였다. 전계 해석 결과를 통해서 메인 접점의 압점력과 절연특성과 고정측 접점 쉴드의 영향을 비교함으로써 차단기 인터럽터 내부의 전계 분포를 확인하고, 전계 강도를 확인함으로 가스절연계폐장치의 적절한 절연내력 확보를 목적으로 한다.