• Title/Summary/Keyword: Loop Breaking

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A Study on Seam Strength according to Sewing Speed (봉제속도에 따른 봉합강도에 관한 연구)

  • 김정진;장정대
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.7
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    • pp.998-1006
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    • 1999
  • This study has investigated the relation between the sewing speed and seam breaking strength applied perpendicular to the seam direction. Breaking strength efficiency breaking mode of seams were examined under various sewing conditions using three kinds of sewing threads and four kinds of fabrics. The results obtained are as follows : 1. According to the increase in sewing speed seam strength was remarkably decreased. Seam strength and its loss difference were shown variously as threads and fabrics were mixed. 2. In case of fabrics with higher strength seam strength showed higher. And the seam strength was determined by the loop strength. 3. In case of fabrics with lower strength seam strength and its difference for every sample showed lower. So the strength of fabrics dominated the seam strength than those of threads. 4. In the experiment using various fabrics and sewing threads there was a type of thread appropriate to each fabric. Fabrics and threads with have similar physical properties were shown proper seam efficiency. 5. The breaking mode was different for every sample seam that was tested.

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A Strategy for Balanced Power Regulation of Energy Storage Systems in a Distribution System during Closed-Loop Operation

  • Han, Yoon-Tak;Oh, Joon-Seok;Cha, Jae-Hun;An, Jae-Yun;Hyun, Seung-Yoon;Lee, Jong-Kwan;Seo, In-Yong;Kim, Jae-Eon
    • Journal of Electrical Engineering and Technology
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    • v.12 no.6
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    • pp.2208-2218
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    • 2017
  • To resolve overload in a distribution system, a distribution system operator (DSO) often performs a load transfer using normally open tie points and switches in the distribution line. During this process, the distribution system is momentarily operated in closed-loop operation. A closed-loop current in the distribution system can cause a power failure due to excess breaking current in the circuit breakers and reclosers. Therefore, it is necessary to calculate the closed-loop current exactly. However, if there are a large number of distributed generation (DG) systems in the distribution system, such as energy storage systems (ESS), they might obstruct the closed-loop operation based on bidirectional power flow. For quick and precise operation of a closed-loop system, the ESS has to regulate the power generation while satisfying closed-loop operation in the worst cases. We propose a strategy for balanced power regulation of an ESS. Simulations were carried out using PSCAD/EMTDC, and the results were compared with calculation results.

Analysis on the Application Capacity of the Superconducting Fault Current Limiter considering Reclosing and Fault Current (전력계통에 초전도한류기 적용시 차단용량 확보를 위한 초전도한류기 적용방안 연구)

  • Kim, Jin-Seok;Lim, Sung-Hun;Kim, Jae-Chul
    • Proceedings of the KIEE Conference
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    • 2015.07a
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    • pp.592-593
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    • 2015
  • Recently, the fault current has increased to exceed the rated breaking capacity of protective device due to the growth of the power demand on the power system where is changed into the loop-, mesh-, network grid. To limit fault current, the superconducting fault current limiter (SFCL) is announced with various methods. In many researches, the current limiting effect with the SFCL has been analyzed considering the rated breaking capacity of the CB with one fault condition. However, the power system has various short circuit and operation conditions. In order to select the capacity of the SFCL with reclosing operation and burden of the fault current on the protective device, the characteristics of the power system were investigated. Through the analysis, the evaluation method of the current rate was improved.

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Optical Current Snesor using Faraday Effect (Faraday 효과를 이용한 광 전류 센서)

  • 김수길
    • Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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    • 2002.11a
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    • pp.97-101
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    • 2002
  • The optical current transformer using Faraday effect is the sensor to measure current that flows in any conductor. This sensor doesn't undergo the magnetic saturation and effect of adjacent conductors. But this senor using bulk-glass sensing element has crucial drawback. It is impossible that the sensor is mounted to conductor without breaking the closed-loop of light or conductor. So we developed the clamp-type optical current transformer and made an experiment.

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Automatic generation of higher level design diagrams (상위 수준 설계 도면의 자동 생성)

  • Lee, Eun-Choul;Kim, Kyo-Sun
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.11
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    • pp.23-32
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    • 2005
  • The automatic generation of circuit diagrams has been practically used in the HDL based design for decades. Nevertheless, the diagrams became too complicated for the designers to identify the signal flows in the RTL and system level designs. In this paper, we propose four techniques to enhance the roadability of the complicated diagrams. They include i) the transformation of repetitive instances and terminals into vector forms, ii) an improved loop breaking algorithm, iii) a flat tap which simplifies the two level bus ripping structure that is required for the connection of a bundle net to multiple buses, and iv) the identification of block strings, and alignment of the corresponding blocks. Towards validating the proposed techniques, the diagrams of an industrial strength design m generated. The complexity of the diagrams has been reduced by up to $90\%$ in terms of the number of wires, the aggregate wire length, and the area.

Interacting network of Hippo, Wnt/β-catenin and Notch signaling represses liver tumor formation

  • Kim, Wantae;Khan, Sanjoy Kumar;Yang, Yingzi
    • BMB Reports
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    • v.50 no.1
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    • pp.1-2
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    • 2017
  • Acquiring a selective growth advantage by breaking the proliferation barrier established by gatekeeper genes is a centrally important event in tumor formation. Removal of the mammalian Hippo kinase Mst1 and Mst2 in hepatocytes leads to rapid hepatocellular carcinoma (HCC) formation, indicating that the Hippo signaling pathway is a critical gatekeeper that restrains abnormal growth in hepatocytes. By rigorous genetic approaches, we identified an interacting network of the Hippo, Wnt/${\beta}$-catenin and Notch signaling pathways that control organ size and HCC development. We found that in hepatocytes, the loss of Mst1/2 leads to the activation of Notch signaling, which forms a positive feedback loop with Yap/Taz (transcription factors controlled by Mst1/2). This positive feedback loop results in severe liver enlargement and rapid HCC formation. Blocking the Yap/Taz-Notch positive feedback loop by Notch inhibition in vivo significantly reduced the Yap/Taz activities, hepatocyte proliferation and tumor formation. Furthermore, we uncovered a surprising inhibitory role of Wnt/${\beta}$-catenin signaling to Yap/Taz activities, which are important in tumor initiation. Genetic removal of ${\beta}$-catenin in the liver of the Mst1/2 mutants significantly accelerates tumoriogenesis. Therefore, Wnt/${\beta}$-catenin signaling, known for its oncogenic property, exerts an unexpected function in restricting Yap/Taz and Notch activities in HCC initiation. The molecular interplay between the three signaling pathways identified in our study provides new insights in developing novel therapeutic strategies to treat liver tumors.

Giant Neurofibroma on Both Buttocks (양측 엉덩이의 거대 신경섬유종)

  • Kim, Ji Hoon;Burm, Jin Sik;Kim, Yang Woo;Kang, So Ra;Kim, Hyoung Kyoung
    • Archives of Plastic Surgery
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    • v.36 no.4
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    • pp.512-515
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    • 2009
  • Purpose: Neurofibromatosis(NF) is an autosomal - dominant systemic disease. Up to fifty percent of patients with NF are reported to have concomitant vascular abnormalities. In the resection of a larger NF, the risk of uncontrolled hemorrhage is much higher due to the difficulty of hemostasis of large vessels within the tumor. We ligated the base of the giant NF with a simple loop - shaped ligation before removal of the giant NF in both buttocks. And then we could successfully reduce the amount of hemorrhage during the operation. Methods: A 46 - year - old female patient presented for giant masses of both gluteal area, which has been growing slowly for the last ten years. Each mass was about $30{\times}20cm$ in size. After designing the elliptical resection margin, we tightened the tumor base by using continuous loop - shaped suture ligation(weaving the thread up and down in a loop - shaped pattern, leaving a space of 2 cm between each loop) with a straight needle and prolene 2 - 0. After skin incision, we proceeded the dissection toward the central and inferior side of the mass obliquely while we avoided breaking large vascular sinuses. We resected the tumor in a wedged - shape. Subcutaneous tissue was sutured layer by layer and skin was closed by vertical mattress and interrupted suture. The loop - shaped ligation of the base was removed and compressive dressing was done with gauzes and elastic bandages. Results: Postoperative complications such as infection, hemorrhage, hematoma, and dehiscense did not occur. Perioperatively the patient was sufficiently transfused with five units of blood and two units of fresh frozen plasma. During the subsequent 1 year follow - up, the functional and cosmetic result was excellent. Conclusion: A continuous loop - shaped suture ligation procedure along the base of the giant NF effectively reduced the amount of hemorrhage during the operation, made dissection and ligation of vessels easily and quickly, and shorten the operating time and postoperative recovery time.

LQ-servo design to command following and output-disturbance rejection (명령추종과 출력측 외란제거를 위한 LQ-servo 설계)

  • Yun, Seong-O;Suh, Byung-Suhl
    • Journal of Institute of Control, Robotics and Systems
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    • v.3 no.5
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    • pp.443-449
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    • 1997
  • LQ-servo design procedure introduced by Athans is a method using a partial states feedback and an output feedback in order to improve the poor performance robustness of the LQR as well as to maintain its stability robustness. Although the method guarantees good stability robustness, it is not effective in performance robustness as it does not match the singular value at low or high frequencies of the transfer matrix obtained by breaking at the plant output. This paper intends propose of a new method, using the limited behaviour of the control gain introduced by Kwakernaak and Sivan, in order to improve it does it refer to controlga introduced by kwakernaak or the new metho Anblguouls.

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Clamp-type Bulk Optic Current Sensor (클램프헝 부피 광 전류센서)

  • Chung, Hyun;Lee, Yong-Wook;Kim, Soo-Gil;Lee, Byoung-Ho;Park, Byoung-Seok
    • Proceedings of the KIEE Conference
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    • 2002.07c
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    • pp.1924-1926
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    • 2002
  • The optical current transformer using Faraday effect is the sensor to measure current that flows in any conductor. This sensor doesn't undergo the magnetic saturation and effect of adjacent conductors. But this senor using bulk-glass sensing clement has crucial drawback. It is impossible that the sensor is mounted to conductor without breaking the closed-loop of light or conductor. So we developed the clamp-type optical current transformer and made an experiment.

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