• Title/Summary/Keyword: 회선류

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Characteristics of Multipath Ultrasonic Flowmeter Installed Upstream and Downstream of Flow Disturbance Factors-Contraction, Expansion, and Tee Pipe (유동교란인자(축소·확대관, Tee관)상하류에 설치된 다회선초음파 유량계의 특성)

  • Lee, Dong-Keun;Cho, Yong
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.36 no.8
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    • pp.877-883
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    • 2012
  • Multipath ultrasonic flowmeters are increasingly being used for the purpose of accurate flow measurement. However, an installation standard has not yet been established for these flowmeters, and this can cause considerable confusion during field installation. There is a need for a minimum straight run to ensure the measurement accuracy of a flowmeter installed upstream and downstream of flow disturbance factors-expansion, contraction, and tee pipes. Experiments were performed by using multipath flowmeters that have less than ${\pm}0.5%$ accuracy-4-paths 1-unit and 2-paths 1-unit are of foreign make, whereas 5-paths 2-units are of domestic make-to determine the straight run under the above conditions. We carried out experiments repeatedly by considering a straight run, velocity, and suggested installation standards for a multipath ultrasonic flowmeter that satisfies the tolerance limits.

Pseudoaneurysm Originating from the Lateral Femoral Circumflex Artery after Retrograde Intramedullary Nailing of a Distal Femur Shaft Fracture (원위 대퇴골 골절에서 역행성 골수 정 시행 후 발생한 외측 대퇴 회선 동맥 기원의 가성동맥류)

  • Yu, Jeongseok;Lee, Beom-Seok;Kim, Han-Bit
    • Journal of the Korean Orthopaedic Association
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    • v.56 no.6
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    • pp.535-539
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    • 2021
  • Vascular complications following a femoral fracture are rare but can result in serious issues. Several case studies have reported pseudoaneurysms occurring after direct trauma or the insertion of a proximal femoral nail in the case of a proximal femoral fracture. The authors encountered an 85-year-old patient treated with retrograde intramedullary nail fixation for a distal femur fracture and suffered a decrease in the hemoglobin level, swelling, and pain on the 9th day after surgery. The authors initially attributed the temporary hematoma and pain to ordinary postoperative processes. On the 16th day after surgery, a pseudoaneurysm originating from the descending branch of the lateral femoral convolutional artery was diagnosed and treated by percutaneous vascular embolization. After the procedure, the hemoglobin level increased, and the swelling and pain decreased.

중핵기술이 되는 홈버스$\cdot$시스템이란 무엇인가?

  • 대한전기협회
    • JOURNAL OF ELECTRICAL WORLD
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    • no.11 s.95
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    • pp.84-87
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    • 1984
  • 정보화의 진전은 바야흐로 기업의 사무분야에만 그치지 않고 가정에도 그 파도가 밀려오고 있다. 가정은 $\ulcorner$생활의 근거지$\lrcorner$이니만큼 $\ulcorner$가정의 정보화$\lrcorner$를 진행시키기 위해서는 각종 정보통신서비스에 대응한 기기류가 유기적으로 결부되어 집밖이 여러 가지 사회시스템과의 통신회선을 통하여 의지의 소통을 충분히 할 수 있는 생활과의 합리성을 가진 시스템의 구축이 중요하다 그래서 이 조사기관에서는 앞으로 가정의 정보화를 원활하게 추진하는데 있어 기술적인 검토뿐만 아니라 서비스 $\cdot$시스템 이미지, 아세스멘트, 맨머시인 인터페이스등의 다각적인 조사연구를 진행해왔다. 여기서는 그 일부로서 1990년대의 서비스$\cdot$시스템 및 금후의 기술표준화 동향에 대해 생각해 보기로 한다.

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Time-Deterministic Event Processing in Terabit Optical-Circuit-Packet Converged Switching Systems (테라비트 광-회선-패킷 통합 스위칭 시스템에서 시간결정성 높은 이벤트 처리에 관한 연구)

  • Kim, Bup-Joong;Ryoo, Jeong-dong;Cho, Kyoungrok
    • Korean Journal of Optics and Photonics
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    • v.27 no.6
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    • pp.212-217
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    • 2016
  • In connection-oriented data-transport services, data loss can occur when the service experiences a problem on its end-to-end path. To promptly resolve this problem, the data-switching systems providing the service should quickly modify their internal configurations distributed among different places in each system. This is performed through a sequence of problem (event) recognition, sharing, and handling procedures among multiple control processors in the system. This paper proposes a method for event sharing and messaging between control processors, to improve the time determinacy of event processing. This method simplifies runtime event sharing and minimizes the time variability caused by the event data, resulting in a decrease in the latency time in processing global events. The proposed method lessens the latency time of global event processing by about 40%, compared to general methods, for 738 internal path changes.

Surgical Management of Multiple Coronary Artery Aneurysms - A case report - (다발성 관상동맥류의 수술적 치료 - 1예 보고 -)

  • Kim, Chang-Young;Park, Kyung-Taek;Kim, Yeon-Soo;Ryoo, Ji-Yoon;Chang, Woo-Ik
    • Journal of Chest Surgery
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    • v.41 no.1
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    • pp.106-109
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    • 2008
  • Multiple coronary aneurysms are rare in adults. The cause may be atherosclerosis, congenital malformations, post-traumatic or post-syphilitic vascular lesions, connective tissue diseases like Marfan and Ehler-Danlos syndromes or Kawasaki disease, all of which cause weakening of the media. Surgical intervention is indicated to prevent rupture, embolization or compression symptoms. The successful management of multiple coronary artery. aneurysms, associated with previous rupture and arrhythmia, originating from proximal potions of ramus intermedius and left circumflex artery are reported.

A Study for Electric Field Intensity of AC/DC Hybrid Transmission Line using Reduced Scale Model (축소모델을 이용한 Hybrid 송전선로의 도체구성별 지표면 전계강도 특성 연구)

  • Lim, Jae-Seop;Shin, Koo-Yong;Kim, Young-Hong;Choi, In-Hyuk;Lee, Dong-Il
    • Proceedings of the KIEE Conference
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    • 2011.07a
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    • pp.503-504
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    • 2011
  • 주파수가 다른 계통을 연계하거나, 장거리 선로 운전시 손실이 낮은 HVDC 송전은 환경문제로 인한 민원으로 새로운 선로건설을 위한 부지확보가 전 세계적으로 어려운 실정이다. 이 문제를 해결할 수 있는 방안으로 기존의 AC선로에 DC를 적용하여 동일철탑에 AC와 DC 선로를 같이 설치하는 하이브리드(Hybird) 선로가 제시되었다. 그러나 AC와 DC가 공존한 상태에서의 전기환경기준이 제시되지 못하고 있는 실정이다. 따라서 본 논문에서는 국내에서 운용중인 345kV 2회선 철탑에 DC선로를 적용한 하이브리드 선로의 축소모델을 제작하였고, DC선로의 도체 구성별 하이브리드 선로의 이온류 특성을 시험하였다.

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Antignawing Activity of Plant Extracts against Mice (식물체 추출물의 생쥐에 대한 갉기억제활성)

  • Yun, Eun-Jun;Lee, Sung-Baek;Lee, Hee-Kwon;Lee, Hoi-Seon;Ahn, Young-Joon
    • Applied Biological Chemistry
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    • v.41 no.1
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    • pp.95-98
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    • 1998
  • Methanol extracts of 54 plant species in 32 families were tested for their antignawing activities against mice by wire-dipping method. The activity varied with plant species. Potent antignawing activity was observed in extracts from roots of Aucklandia lappa (Compositae), barks of Cinnamomum cassia (Lauraceae), fruits of Illicium verum (Magnoliaeceae), fruits of Piper nigrum (Piperaceae), rhizomes of Rheum officinale (Polygonaceae), and leaves of Pinus densiflora (Pinaceae). As naturally occurring rodent repellents, these plant-derived materials could be useful as a preventive agent against various kinds of damage caused by rodents.

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Useful Insects : Study on Behavior of Fruits Feeding and Ovipositional Characterization of Its Adult in Pylocoelia rufa (유용곤충 산업화를 위한 늦반딧불이 유충의 과일류에 대한 섭식행동과 성충의 산란특성 연구)

  • Lee, Hee-Kwon;Lee, Hoi-Seon
    • Korean Journal of Organic Agriculture
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    • v.24 no.4
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    • pp.859-867
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    • 2016
  • This study was conducted at rearing room to investigate the feeding behavior of fruits in the firefly (Pylocoelia rufa) larvae and the ovipositional characteristics of the adults. As a result, the pear, apple, melon, persimmon, mandarin, grape and peach were shown the feeding behavior of larvae the average 6.40, 3.25, 2.50, 2.20, 2.00, 1.40 and 1.25, respectively. However, the larvae were not shown at all feeding behavior to banana. The hours feeding behavior of firefly larvae was primarily from 8:00 pm until 2:00 am. In addition, the time at which the voracious feeding behavior was until 8:00 pm to 12:00 pm. The 6:00 pm began whisking all the larvae are hiding in the shelter. In the case of the firefly larvae fed only the edible snail, the adults were oviposition an average $49{\pm}6$ eggs. At that time larva stage, adults of the firefly eating the pears, apples, melon and eat edible snail at the same time there were oviposition the $53{\pm}7$ on average. In the case of fruits, the pears, apples, and melons has been considered worthy to take the firefly larva fed with the current land snails.

An Optimal Capacity Allocation Problem in Designing advanced Information Communication Processing System (대용량 통신처리시스템에서 사용자 이용성향과 ISDN를 고려한 망정합장치의 회선용량 분배에 관한 연구)

  • 김영일;김찬규;이영호;김영휘;류근호
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.25 no.5B
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    • pp.809-819
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    • 2000
  • This paper deals with an optimal capacity allocation problem and performance analysis in Advanced Information Communication Processing System(AICPS). AICPS is a gateway system interconnection PSTN(Public Switched Telephone Network), ISDN(Intergrated Services Digital Network), PSDN(Packet Switched Data Network), internet, Frame Relay and ATM together. This study considers not only ISDN and Internet but also user behavior of On-line service which is analyzed by Markov process. A call blocking probability of TNAS and INAS is computed by Erlang's formula. Then, PNAS and WNAS's call blocking probability are computed by Stochastic knapsack modeling. The result is compared with result of simulation. Finally, we allocate an optimal capacity minimizing total call blocking probability.

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