• 대한전기학회논문지:전력기술부문A
• /
• 제53권10호
• /
• pp.550-555
• /
• 2004

Fault section isolation and service restoration are very important for function of DAS. In Japan, a progressive protection method is used for the line to ground fault section isolation and service restoration. But the progressive protection method has a drawback that the customer will experience outage time and that the rate in use of the feeder is not over 50%. This paper presents a new Service Restoration Algorithm which is for the line to ground fault section isolation and service restoration method for a ungrounded distribution system. If the proposed algorithm is used, the rate in use of the feeder can improve than before because a distribution system can change multi connection of feeder and the customer's outage time can be reduced. The proposed algorithm has been successfully tested in a distribution system.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2003년도 하계학술대회 논문집 A
• /
• pp.299-301
• /
• 2003

In this paper, a protection system using Multi-Agent concept for power distribution network is proposed. Multi agent system consist of Feeder agent, OCR(Over Current Relay) agent, Recloser agent and Switch agent. An agent calculates and corrects its parameter by itself through communication with neighboring agents and its own intelligence algorithm. Simulations in a simple distribution network show the effectiveness of the suggested protection system. Multi-Agent System, protection of distribution network, Communication.

• 대한전기학회논문지:전력기술부문A
• /
• 제55권6호
• /
• pp.227-235
• /
• 2006

In this paper, autonomous separation methodology of faulted section based on network is proposed newly, which can minimize the outage effect as compared with the existing center-based faulted section separation method by determining and separating autonomously the faulted section by the free operation information exchange among IEDs on the feeder of distribution system. The all IEDs is designed in network in which client/server function is possible in order to separate autonomously the faulted section using PtP(Peer to Peer) communication. Also, Inference based solution of IED for the autonomous faulted section separation is designed by rules obtained from the analyzing results of distribution system topology. Here, the switch IEDs transmit on network the fault information utilizing on multi-casting communication method, at the fame time, determine selfly whether they operates or not by inferencing autonomously the faulted section using the inference-based solution after receiving the transmitted information. Finally, in order to verify the effectiveness and application possibility of the proposed methodology, the diversity fault cases are simulated for the typical distribution system.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2007년도 제38회 하계학술대회
• /
• pp.497-498
• /
• 2007

When we implement the substation automation, the largest problem is that IEDs may come from different vendors, which will result in the reduction of the reliability of communication between IEDs. To solve the problem IEC61850 is investigated, which uniforms the communication interface. However, in order to communicate with an IEC61850 implanted IED, FRTU (Feeder Remote Terminal Unit) need to be compatible with IEC6185 consequentially. A new IEC61850 based FRTU development scheme is proposed. The performance shows his compatibility with other IEC61850 IED, which has already been tested in ARET (Agent-based Reliability Enhancement Technology) system.

• Korean Journal of Radiology
• /
• 제20권8호
• /
• pp.1285-1292
• /
• 2019

Objective: To evaluate the safety and efficacy of the coil-protected technique for liquid embolization in neurovascular malformations. Materials and Methods: Twenty-two patients who underwent coil-protected liquid embolization for symptomatic cranial (n = 13) and spinal (n = 9) arteriovenous fistula (AVF) or arteriovenous malformations (AVMs) were identified. A total of 36 target feeder vessels were embolized with N-butyl cyanoacrylate and/or Onyx (Medtronic). This technique was used to promote delivery of a sufficient amount of liquid embolic agent into the target shunt or nidus in cases where tortuous feeding arteries preclude a microcatheter wedging techniqu and/or to prevent reflux of the liquid embolic agent in cases with a short safety margin. The procedure was considered technically successful if the target lesion was sufficiently filled with liquid embolic agent without unintentional reflux. Angiographic and clinical outcomes were retrospectively evaluated. Results: Technical success was achieved for all 36 target feeders. Post-embolization angiographies revealed complete occlusion in 16 patients and near-complete and partial occlusion in three patients each. There were no treatment-related complications. Of the six patients who showed near-complete or partial occlusion, five received additional treatments: two received stereotactic radiosurgery for cerebral AVM, two underwent surgical removal of cerebral AVM, and one underwent additional embolization by direct puncture for a mandibular AVM. Finally, all patients showed complete (n = 19) or near-complete (n = 3) occlusion of the target AVF or AVM on follow-up angiographies. The presenting neurological symptoms improved completely in 15 patients (68.2%) and partially in seven patients (31.8%). Conclusion: The coil-protected technique is a safe and effective method for liquid embolization, especially in patients with various neurovascular shunts or malformations who could not be successfully treated with conventional techniques.

• 한국동물위생학회지
• /
• 제42권4호
• /
• pp.237-243
• /
• 2019

Avian reovirus (ARV) is the pathogenic agent of tenosynovitis and malabsorption syndrome in broiler, which has caused significant economical losses due to poor feeder efficiency and stunting. In order to determine the prevalence of ARV infection in poultry farms in Jeonbuk province, Korea, we performed a surveillance study by testing 179 cecal samples from 131 broiler farms for virus detection, and 1,181 serum samples from 33 broiler farms (n=292) and 22 broiler breeder farms (n=1,525) for antibody detection in the province. Virological examination using RT-PCR showed that ARV were detected in 26.0% of the tested farms (34/131),with the highest positive rates in broilers of 6 days old or more in summer season. In serological test using ELISA, broiler and broiler breeder farms examined were all ARV antibody positive. In broiler, the positive rate and antibody titers showed a tendency to decrease with age in contrast to those of broiler breeders. Our results indicate that ARV is ubiquitous in broilers and broiler breeders in the province.

• 보존과학회지
• /
• 제23권
• /
• pp.95-102
• /
• 2008

유기질 문화재 보존 천연 살생물제 개발을 위한 후보물질 조사를 위해 국내 자생하는 11종 수목을 대상으로 각 수목 메탄올 추출물의 9종 목재오염균과 궐련벌레 성충에 대한 항진균 및 살충활성을 조사하였다. 항진균 활성은 목재부후균과 표면오염균에 대해 각각 paper disc soaking 방법과 feeder strip 방법으로 측정되었다. 그 결과, 수목 중 황벽(Phellodendron amurense) 메탄올 추출물은 5 mg/disc에서 Coniophora puteana, Lentinus lepideus, Tyromyces palustris 그리고 Aspergillus niger에 대해 우수한 항균활성을 나타냈다. 또한, 수목 메탄올 추출물의 살충활성은 topical application 방법에 의해 측정되었으며 특히 주목(Taxus cuspidata)과 전나무(Abies holophylla) 메탄올 추출물을 궐련벌레 성충에 25 ${\mu}g$/adult의 농도로 24시간 처리했을 때 56.7%의 치사율을 보였다. 위의 결과로부터 주목과 전나무 그리고 황벽 메탄올 추출물은 각각 충과 목재오염균에 의해 야기되는 생물학적 열화에 대한 유기질 문화재 보존을 위해 유용하게 사용가능할 것으로 사료된다.

• 식물병연구
• /
• 제25권4호
• /
• pp.237-242
• /
• 2019

상추 시설재배지에서 해바라기침선충(Paratylenchus projectus)에 의한 피해가 발생하였다. 피해발생 시설에서 약 3개월 정도 상추를 재배하고 있었는데 상품성이 있는 상추는 전혀 생산되지 않았다. 피해 상추는 잔뿌리가 거의 없었고 굵은 뿌리는 푸석하게 부풀어 코르크화 현상이 발생했었다. 본 시설하우스에서 발견된 침선충 밀도는 토양 100 ㎤ 당 평균 3,296마리(320-11,600)로 매우 높았고 본 시설하우스의 흙을 사용하여 상추를 정식하여 실험한 결과, P. projectus 접종구에서 30% 정도 상추 생육의 저하가 발생하였다. 따라서 이 증상을 해바라기 침선충(P. projectus)에 의한 "상추 뿌리 코르크병"으로 명명하고자한다.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제2권2호
• /
• pp.173-180
• /
• 2001

The stink bug, Eocanthecona furcellata (Wolff.) is a natural and potential biocontrol agent of Spilarctia obliqua (Walk.). The present investigation reveals the biology, predatory efficiency and reproductive parameters of the predator which feeds on S. obliqua caterpillars in mulberry plantation. In order to find out the role of prey sine on the biology of the predators the predatory insects were separately fed with small and large caterpillars of S. obliqua. The incubation period of the eggs of E. furcellata was 8.37${\pm}$0.44 days, while the nymphal duration varied as per the prey sine. The predator when supplied with small larvae of prey, consumed 61.1 larvae and completed nymphal stage in 19.9 days; while those fed with larger prey, consumed 36.1 larvae and completed their nymphal stage in 21.55 days. The prey size also influences the reproductive parameters of the predator, The adult female predator is more voracious feeder than the adult male and consumed 41.9${\pm}$0.64 small larvae and 42.2${\pm}$0.87 large larvae during their life span. The longevity of male and female was observed as 20.7 and 29.4 days respectively. Visualization of the predator as well as the movement of the prey increases the predatory efficiency. Scanning electron microscopic studies on the feeding part explain its support in effective predation. Field observations indicated a drastic fall in the incidence of the mulberry pest, S. obliqua with the increased population E. furcellata in mulberry plantation.