• 대한용접접합학회:학술대회논문집
• /
• 대한용접접합학회 1998년도 특별강연 및 추계학술발표 개요집
• /
• pp.11-24
• /
• 1998

The invention of fusion wilding technology has brought on a revolutionary change in manufacturing industry which enables the construction of large scale high temperature plants in chemical, petrochemical and power generation industries. However, among the failure cases of high temperature components, premature failures of weldments have taken a large percentage that indicates the detrimental effect of welding on structural integrity. The accurate prediction of the high temperature behaviour of welded components is thus becoming increasingly important in order to realise an optimised design and maintenance of a plant life. In the present paper, recent research activities on high temperature behaviour of welded structures are briefly summarised. A local deformation measuring technique is proposed to determine the creep properties of weldment constituents. A damage mechanics approach is introduced to study the life reduction and ductility reduction due to the presence of a weld in high temperature structures. Finally, the high temperature creep crack growth in weldments is discussed.

• 한국환경과학회지
• /
• 제9권5호
• /
• pp.389-392
• /
• 2000

In this study a packed tower was selected for the treatment apparatus of $NH_3$ gas produced in industry. Formerly latticework packing has been used in preventive facility of treatment of $NH_3$ gas. However recently metallic Ralu-Pack 250YC. structured packing is usually being used in petrochemical production plant. This study is for the application the packing to the $NH_3$ gas treatment in wet scrubbing process. In Air/water system hydraulic pressure drop dependent of specific liquid load and gas capacity factor was continuous and parallel from graph. The tower height can be determuined by the number of transfer unit and the height of transfer unit influenced on liquid distribution.

• 한국산업안전학회:학술대회논문집
• /
• 한국안전학회 2000년도 춘계 학술논문발표회 논문집
• /
• pp.196-196
• /
• 2000

This paper presents an approach for modeling of the generation of a set of credible accident scenarios for a petrochemical plant, which will be used to perform quantitative hazard assessments such as the consequence assessment, FTA or ETA. This approach is carried out in ways of identifying, classifying a set of major components and elements for scenarios generation by analysis of the informations on various actual accidents, and thus setting priorities of both factors of likelihood and consequence on each component or element identified.

• 한국소음진동공학회논문집
• /
• 제15권9호
• /
• pp.1060-1069
• /
• 2005

Silencers are engineering devices that are designed to attenuate sound waves propagating in a flowing medium. The muffler type silencer has a series of chambers in parallel or series utilizing the reflection and expansion characteristics of the expansion chambers, sidetubes, branch resonators, and tailpipes to attenuate the sound. To Improve the performance of industrial blower silencer of muffler type which is employed in petrochemical plant, this paper seeks its optimal arrangement of buffs by experimental method and suggests optimal arrangement of buffs. Experimental results show that the optimal one suggested can reduce the noise level as much as 14 dB (or 18 dB(A)) in the laboratory and as much as 4 dB(A) compared to that of the existing silencer on the ground.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 심포지엄 논문집 정보 및 제어부문
• /
• pp.235-236
• /
• 2007

정유 공정에 사용되는 탱크 종류에는 여러 가지가 존재하는데, 랭크마다 각기 다른 물질을 저장한다. 이런 특징 때문에 기존 관계형 데이터베이스를 이용한다면 저장 공간의 문제점이 발생하므로 객체지향 데이터베이스를 이용한다. 관계형 데이터베이스와의 가장 큰 차이점은 우선, 객체지향 데이터베이스이므로 OOP 개념을 데이터베이스에서 이용 가능하다. 그러한 특징으로 인하여 상속, 재 사용성, Class에 메소등 작성을 이용하여 ATOM(Advanced Tank Operation Management) 데이터베이스를 설계한다. 본 논문에서는 ATOM을 설계하고, 공정 Operator를 구축하므로서 효율적인 석유화학 공장의 탱크 운용 시스템을 구현하고자 한다.

• Nuclear Engineering and Technology
• /
• 제49권1호
• /
• pp.196-208
• /
• 2017

This study presents an experimental work in a petrochemical company for scanning a buried pipeline using $Tc^{99m}$ radiotracer based on the measured velocity changes, in order to determine the flow reduction along a pipeline. In this work, $Tc^{99m}$ radiotracer was injected into the pipeline and monitored by sodium iodide scintillation detectors located at several positions along the pipeline. The flow velocity has been calculated between every two consecutive detectors along the pipeline. Practically, six experiments have been carried out using two different data acquisition systems, each of them being connected to four detectors. During the fifth experiment, a bypass was discovered between the scanned pipeline and another buried parallel pipeline connected after the injection point. The results indicate that the bypass had a bad effect on the volumetric flow rate in the scanned pipeline.

• KSBB Journal
• /
• 제27권1호
• /
• pp.9-15
• /
• 2012

Antimicrobial peptides are widely used in various organisms as a defense system against infection. The peptides are lethal towards bacteria and fungi, however have minimal toxicity in mammalian and plant cells. In this aspect, it is considered that antimicrobial peptides are new alternative materials for defensing against microbial infection. Here, we describe overall characteristics of antimicrobial peptides based on the mechanism of action, classification of the peptides, report detection/screening methods and chemical/biological production. It is expected that understanding of innate immune system based on antimicrobial peptides tends to develop novel natural antimicrobial agents, which might be applied for defensing pathogenic microorganisms resistant to conventional antibiotics.

• The Plant Pathology Journal
• /
• 제20권4호
• /
• pp.258-263
• /
• 2004

Ripe fruit of pepper (Capsicum annuum) showed resistance to Colletotrichum gloeoporioides, but unripe fruit was susceptible. We previously isolated the PepTLP gene that induced in both unripe and ripe fruit by fungal infection and wound, and only in ripe fruit by jasmonic acid (JA) treatment. To examine further regulation of PepTLP, the action of specific agonist and antagonists of known signaling effector on the .PepTLP expression by fungal infection, wound, and JA was investigated. A similar dephosphorylation event negatively activated all the PepTLP expression in the ripe fruit by fungal infection, wound, and JA. The induction of PepTLP expression by wound is differentially regulated via phosphorylation and dephosphorylation step during pre- and post-ripening, respectively. In addition, the induction of PepTLP expression in the ripe fruit by wound and JA is differentially regulated via dephosphorylation and phosphorylation step, respectively. Only both wound and JA treatment has synergistic effect on the PepTLP expression in the unripe fruit. Both SA and JA treatments on the unripe fruit, and both wound or JA and SA on the ripe fruit could not do any effect on the expression of PepTLP. These results suggest that the induction of PepTLP expression is differentially regulated via complex regulatory system against fungal infection, wound, and JA treatment during pre- and post-ripening of pepper fruit.

• 한국안전학회지
• /
• 제28권3호
• /
• pp.44-50
• /
• 2013

Process gas piping is one of the most basic components frequently used in the refinery and petrochemical plants. Many kinds of by-product gas have been used as fuel in the process plants. In some plants, natural gas is additionally introduced and mixed with the byproduct gas for upgrading the fuel. In this case, safety or design margin of the changed piping system of the plant should be re-evaluated based on a proper design code such as ASME or API codes since internal pressure, temperature and gas compositions are different from the original plant design conditions. In this study, series of piping stress analysis were conducted for a process piping used for transporting the mixed gas of the by-product gas and the natural gas from a mixing drum to a knock-out drum in a refinery plant. The analysed piping section had been actually installed in a domestic industry and needed safety audit since the design condition was changed. Pipe locations of the maximum system stress and displacement were determined, which can be candidate inspection and safety monitoring points during the upcoming operation period. For studying the effects of outside air temperature to safety the additional stress analysis were conducted for various temperatures in $0{\sim}30^{\circ}C$. Effects of the friction coefficient between the pipe and support were also investigated showing a proper choice if the friction coefficient is important. The maximum system stresses were occurred mainly at elbow, tee and support locations, which shows the thermal load contributes considerably to the system stress rather than the internal pressure or the gravity loads.

• 한국재난정보학회 논문집
• /
• 제13권3호
• /
• pp.305-312
• /
• 2017

우리사회는 고도화, 첨단화, 정보화 산업들이 지속적으로 성장을 거듭하여 현재는 4차 산업 혁명의 시대에 살고 있다. 산업이 발달함에 따라 사용자의 부하도 다양하게 급증하였고 이는 에너지 부족 현상으로 심화되어 추가적인 에너지 시설의 건설이 요구되고 있는 실정이다. 이에 해안 지역을 중심으로 에너지 플랜트 건설공사가 활발히 진행되고 있다. 특히, 발전소 가스 석유화학 플랜트 등의 건설 시 국토가 부족한 우리나라의 실정을 고려하여 타 지역의 토양으로 해안을 매립하고 그 지반에 플랜트 시설을 건축하는 방식으로 시행되고 있다. 현재의 국내 접지 설계는 전기설비설계기술기준에 근거한 접지저항만을 용도에 맞게 결정하는 설계와 시공이 이루어지고 있다. 하지만 이렇게 검증되지 않은 매립된 토양에 건립한 플랜트 시설에 뇌격전류 및 이상전류 유입 시 대지 전위상승으로 인한 설비 운용자나 사용자가 감전재해 위험에 심각하게 노출 되게 된다. 따라서 플랜트 시설의 부하 특성에 최적화된 접지시스템이 요구되고 있어, 본 논문에서는 매립된 토양의 대지고유저항을 분석하고 KS C IEC 61936-1 규격을 적용한 컴퓨터 프로그램(CDEGS)을 활용하여 감전재해를 일으키는 접촉전압과 보폭전압을 해석하여 플랜트 설비에 최적화된 접지설계를 제안하고자 한다.