• The Transactions of the Korean Institute of Power Electronics
• /
• v.4 no.2
• /
• pp.128-137
• /
• 1999

Recently the pelionnance of CO2 arc welding machine has been advanced significantly through the adoption of i invelter circuit topology. which made it possible to improve welding perfonnances such as spatter generation and bead s state. But the conventional inverter arc welding machine generates constant output voltage which cause much spatter g generation dUling short-circuit and arc start time because it is unable to control output current instantaneously. So this p paper representes wavefCnm controlled inverter arc welding machine which control the wavefonn of welding current and t thus to suppress the spatter generation. And the system designed in this paper is the digital controller using single chip m microprocessor of 80C196KC. As a result of perfonnance test for this system, the spatter generation is reduced and s shOlt-circuit time period is stabilized compared to conventional one. And more by using switched mode rectifier for A AC/DC power convelter. unity power factor is maintained and low order halmonic spectrum is supressed.

• Journal of Aquaculture
• /
• v.6 no.4
• /
• pp.255-271
• /
• 1993

For the development of seedling production techniques of the freshwater crab Eriocheir japonicus, the effects of salinity and temperature on the growth of larvae of the crab were studied. Embryos hatched out as zoea larvae were measured 0.421 mm in average carapace length. Five zoea stages needed 16-26 days for metamorphosis from zoea to megalopa at $22^{\circ}C$ and $24.5\%o$. The average carapace length of the 5th zoea was 1.16 mm and that of the megalopa larvae was 1.89 mm. Each zoea stage could be identified based on both the number of plumosed seatae on the exopodite of maxilliped, and the number of spines on the posteroinner margin of tel son and also based on the rudimentary pleopods appearence. Zoea larvae fed rotifers and Artemia nauplii were healthy and metamorphosing rate from zoea to megalopa was $80\~90\%\;at\;22\~26^{\circ}C\;and\;17.5\~31.5\%o$. The relationship between larval period (Y in days) and water temperature $(X\;in\;^{\circ}C)$ is expressed as Log Y = 3.8604-1.91735 LogX. Water temperature and salinity ranges for better survival and metamorphosis of the larvae were $ 22^{\circ}C\~26^{\circ}C\;(optimum\;at\; 26^{\circ}C)\;and\;17.5\%o\~31.5\%o\;(optimum\;at\;24.5\%)$, respectively. The duration of larval stages tend to longer as salinity levels deviated from optimum particulaly at lower end. All zoea larvae did not survive in freshwater.

• Journal of the korean veterinary medical association
• /
• v.48 no.9
• /
• pp.536-539
• /
• 2012

건유기에서 비유기로의 이행기는 젖소에서 위험률이 높은 시기이고 이 시기에 가장 큰 문제가 될 수 있는 것이 유방염이다. 환경성 세균들이 분만 전후기에 가장 문제가 될 수 있는 병원체이다. 대장균군에 속하는 세균들은 경산우에서 심각한 감염을 일으킬 수 있고, 처녀우의 경우는 coagulase-음성 포도상구균에 감염될 가능성이 높다. 분만 전후기 중에는 호르몬이나 기타 요인들로 인해 젖소들의 면역상태가 다소 억압된다. 성공적인 유방염 방제 프로그램은 건유우, 분만우, 및 처녀우의 관리에 초점을 맞춰야 한다. 청결하고 안락한 환경, 적절한 사료공급, 비타민과 미량 원소가 함유된 적절한 사료의 보충이 유방 건강을 유지하는데 필수적이다. 건유 시작할 때 유두관의 폐쇄를 강화하고 케라틴 마개가 형성될 때까지 유두 끝을 세균으로부터 보호해 줄 전략들을 사용해서 분만 후의 유방염 감염 위험을 감소시켜야 한다. 건유기 치료는 상당히 성공적으로 이용되어 왔지만 전체적으로 실시하기 보다는 선택적으로 치료하는 접근법이 권장된다. 환경성 유방염에 감염될 위험이 높은 우군에서는 항생제 이외의 접근법이 건유기 중의 신감염 예방을 위한 유용한 도구가 될 수 있다.

• Journal of the korean veterinary medical association
• /
• v.46 no.11
• /
• pp.1011-1025
• /
• 2010

국내 젖소 우군 사육규모의 다두화, 고능력우의 증가에 따라 발정발견의 실패, 미약발정와 건유기 및 이행기에 영양관리, 건강관리, 생리적 또는 환경적인 스트레스의 증가에 따라 번식률이 저하되고 있는 실정에 있다. 또한 우군 규모가 대규모화로 젖소에서 발생하는 질병의 대부분이 분만을 중심으로 100일간에 집중되어 발생하고 있어, 우군 질병의 제어가 중요하다. 또한 분만 전 후의 산욕기에 대사성 질병의 증가에 따라 번식장애를 초래하는 경우가 많으므로 이에 대한 예방관리가 중요하다 하겠다. 따라서 소에서 산욕기의 생리 및 질병예방프로그램, 소 임신 진단요령과 번식률 제고를 위한 발정과 배란의 control의 처치에 응용되고 있는 최근의 프로그램에 관한 응용의 실제를 소개하고자 한다.

• Korea Trade Review
• /
• v.41 no.5
• /
• pp.187-211
• /
• 2016

This study discusses the right of suspension of performance against anticipatory breach under SGA. Anticipatory breach originated in Hochster v De La Tour allows the innocent party to exercise immediately the right or rights reserved for the non-performance of obligations. But it has not been codified in English Law. Instead, under SGA s. 41 and s. 44, the seller may suspend his performance against the buyer' anticipatory breach. Lien under s. 41 and stoppage in transit under s. 44 are given only to the seller in a narrowly-defined situation. Under SGA s. 41, the unpaid seller is entitled to retain possession of goods where the buyer becomes insolvent. But under SGA s. 43, the unpaid seller loses the right of lien when he delivers goods to a carrier or other bailee or custodian for the purpose of transmission to the buyer without reserving the right of disposal, or when the buyer or his agent lawfully obtains possession of the goods, or by waiver of lien. Under SGA s. 44, the unpaid seller may exercise the right of stoppage in transit if the buyer becomes insolvent, despite the fact that the property of goods has passed or a bill of lading has been transferred to the buyer. But, under s. 45, the right of stoppage in transit is ended when the buyer or his agent takes delivery of goods. And where the buyer transfers a bill of lading to a sub-buyer, the unpaid seller loses his right to stop goods in transit.

• Proceedings of the Korean Institute of Communication Sciences Conference
• /
• 1996.10a
• /
• pp.732-735
• /
• 1996

• Proceedings of the Korea Concrete Institute Conference
• /
• 2009.05a
• /
• pp.487-488
• /
• 2009

In this investigation, the special fiber mixing method was studied for increasing the acoustic absorption properties of porous concrete. The short fibers were mixed as the fuzzy-shape, not as the embedded, and the specimens are measured using the impedance tube method.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2009.05a
• /
• pp.489-490
• /
• 2009

In this study, the experiment was carried out to investigate the effect of metakaolin on the compressive strength of lightweight aggregate cellular concrete. For this purpose, five level replacement ratio of metakaolin were selected.

• Proceedings of the Korean Vacuum Society Conference
• /
• 1997.02a
• /
• pp.49-49
• /
• 1997

• Proceedings of the Computational Structural Engineering Institute Conference
• /
• 2007.04a
• /
• pp.441-444
• /
• 2007

This paper presents a part of micormechanics-based elastic modeling (Lee and Pyo, 2007) of particle-reinforced composites containing slightly weakened interfaces. The Eshelby's tensor for a damaged ellipsoidal inclusion to model particles with slightly weakened interfaces is incorporated into a micormechanical formulation by Ju and Chen (1994). A damage model in accordance with the Weibull's probabilistic function is also developed to simulate the progression of weakened interface in the composites.