• Title/Summary/Keyword: split feasibility

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EXTRA-GRADIENT METHODS FOR QUASI-NONEXPANSIVE OPERATORS

  • JEONG, JAE UG
    • Journal of applied mathematics & informatics
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    • v.34 no.5_6
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    • pp.467-478
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    • 2016
  • In this paper, we propose an Ishikawa-type extra-gradient iterative algorithm for finding a solution of split feasibility, fixed point problems and equilibrium problems of quasi-nonexpansive mappings. It is proven that under suitable conditions, the sequences generated by the proposed iterative algorithms converge weakly to a solution of the split feasibility, fixed point problems and equilibrium problems. An example is given to illustrate the main result of this paper.

Design and Development of Low-Cost Switched Reluctance Motor Drive System (저가형 스위치드 릴럭턴스 모터 드라이브 시스템 개발)

  • Ha, Keun-Soo
    • The Transactions of The Korean Institute of Electrical Engineers
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    • v.58 no.11
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    • pp.2162-2167
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    • 2009
  • A Low cost and variable speed brushless motor drive system with single switch per phase is presented. The motor drive is realized with a novel two-phase flux-reversal-free switched reluctance motor and a split AC two switch converter. The strategy of the controller and the converter for its realization are described. Comparisons between a split AC converter, asymmetric converter, split DC converter, single controllable switch converter, and N+1 converter are performed for its device rating, cost, switching losses and conduction losses, and converter efficiency. The split AC converter is analyzed and simulated to verify the characteristics of the converter circuitry and control feasibility and the simulation results are presented. The efficiency with various loads is numerically estimated and experimentally compared from viewpoint of subsystem and system in details. The focus of this paper is to compare the presented motor drive system to the asymmetric converter system throughout experiments and demonstrate single switch per phase converter having comparable efficiency as the asymmetric converter system.

OUTER APPROXIMATION METHOD FOR ZEROS OF SUM OF MONOTONE OPERATORS AND FIXED POINT PROBLEMS IN BANACH SPACES

  • Abass, Hammad Anuoluwapo;Mebawondu, Akindele Adebayo;Narain, Ojen Kumar;Kim, Jong Kyu
    • Nonlinear Functional Analysis and Applications
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    • v.26 no.3
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    • pp.451-474
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    • 2021
  • In this paper, we investigate a hybrid algorithm for finding zeros of the sum of maximal monotone operators and Lipschitz continuous monotone operators which is also a common fixed point problem for finite family of relatively quasi-nonexpansive mappings and split feasibility problem in uniformly convex real Banach spaces which are also uniformly smooth. The iterative algorithm employed in this paper is design in such a way that it does not require prior knowledge of operator norm. We prove a strong convergence result for approximating the solutions of the aforementioned problems and give applications of our main result to minimization problem and convexly constrained linear inverse problem.

Feasibility of the Use of RapiGraft and Skin Grafting in Reconstructive Surgery

  • Yang, Jung Dug;Cho, In Gook;Kwon, Joon Hyun;Lee, Jeong Woo;Choi, Kang Young;Chung, Ho Yun;Cho, Byung Chae
    • Archives of Plastic Surgery
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    • v.43 no.5
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    • pp.418-423
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    • 2016
  • Background Skin grafting is a relatively simple and thus widely used procedure. However, the elastic and structural quality of grafted skin is poor. Recently, various dermal substitutes have been developed to overcome this disadvantage of split-thickness skin grafts. The present study aims to determine the feasibility of RapiGraft as a new dermal substitute. Methods This prospective study included 20 patients with partial- or full-thickness skin defects; the patients were enrolled between January 2013 and March 2014. After skin defect debridement, the wound was divided into two parts by an imaginary line. Split-thickness skin grafting alone was performed on one side (group A), and RapiGraft and split-thickness skin grafting were used on the other side (group B). All patients were evaluated using photographs and self-questionnaires. The Manchester scar scale (MSS), a chromameter, and a durometer were used for the scar evaluation. The average follow-up period was 6 months. Results The skin graft take rates were 93% in group A and 89% in group B, a non-significant difference (P=0.082). Statistically, group B had significantly lower MSS, vascularity, and pigmentation results than group A (P<0.05 for all). However, the groups did not differ significantly in pliability (P=0.155). Conclusions The present study indicates that a simultaneous application of RapiGraft and a split-thickness skin graft is safe and yields improved results. Therefore, we conclude that the use of RapiGraft along with skin grafting will be beneficial for patients requiring reconstructive surgery.

Design Formula for the Flexural Strength of a Double Split Tee Connection (상·하부 스플릿 T 접합부의 휨강도 설계식)

  • Yang, Jae-Gue;Kim, Joo-Wo;Kim, Yu
    • Journal of Korean Society of Steel Construction
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    • v.24 no.5
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    • pp.511-520
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    • 2012
  • The double split Tee connection, a type of full strength-partially restrained connection, has adequate flexural strength according to the changes in the thickness of the T-stub flange and the gauge distance of the high-strength bolts. Moreover, the double split Tee connection is designed and constructed with seismic connections that have enough ductility capacity applicable to ordinary moment frame and special moment frame by grade of steel, size of beam and column and geometric connection shape. However, such a domestic research and a proposal of a suitable design formula about the double split Tee connection are insufficient. Thus, many experimental and analytical studies are in need for the domestic application of the double split Tee connection. Therefore, this study aimed to examine and suggest feasibility of a design formula of the double split Tee connection of FEMA.

Guided wave analysis of air-coupled impact-echo in concrete slab investigation on the use of waste tyre crumb rubber in concrete paving blocks

  • Murugan, R. Bharathi;Natarajan, C.
    • Computers and Concrete
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    • v.20 no.3
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    • pp.311-318
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    • 2017
  • This paper investigates the utilization of waste tyre crumb rubber as the fine aggregate in precast concrete Paving block (PCPB). PCPB's are generally preferred for city roads, pedestrian crosswalk, parking lots and bus terminals. The main aim of this paper is to evaluate the mechanical properties of wet cast PCPB containing waste tyre crumb rubber. The mechanical properties were investigated using a density, compressive strength, split tensile strength and flexural strength tests at 7, 28 56 days according to the IS 15688:2006 and EN1338. The wet cast method was followed for producing PCPB samples. The fine aggregate (river sand) was replaced with waste tyre crumb in percentage of 5%, 10%, 15%, 20% and 25% by volume. All the test results were compared with the conventional PCPB (Without rubber). The test results indicate its feasibility for incorporating waste tyre crumb rubber in the production of PCPB by the wet cast method.

Design of Wedge Projection System with Thin Slab Structure

  • Lee, Taewon;Choi, Sungwon;Yang, Yucheol;Min, Sung-Wook
    • Journal of the Optical Society of Korea
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    • v.18 no.6
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    • pp.679-684
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    • 2014
  • Enhanced analysis is performed to design a wedge projection system with a slab structure that increases the projected image size. The specification values of the system such as the length of the slab structure and the imaging region are calculated and investigated using an optical simulation tool. We also propose a split imaging region method to represent a large tiled scene using the thin wedge waveguide structure. Experiments are performed to verify the feasibility of the proposed method.

Feasibility Study of Laser Contact Angle Measurement for Nano-fiber Characterization (나노섬유의 특성분석을 위한 레이저 접촉각 측정기의 효율성 연구)

  • 신경인;안선훈;김성훈
    • Journal of the Korean Society of Clothing and Textiles
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    • v.27 no.5
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    • pp.554-559
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    • 2003
  • A newly developed contact angle measurement instrument by laser beam projection allows for rapid and direct determination of contact angles. The instrument may have a possibility to characterize newly developed nano-fibers. When the laser beam impinges on an edge of an interface of liquid and solid, projected beam were split across and made two straight lines on a tangent screen. From the result, it could measure the contact angle directly by reading the angle between two split beams. The purpose of this study was to prove reliability and reproducibility of the contact angle measurement instrument by laser beam projection compare to the conventional one by microscope through the comparative experiment and questionnaire. Test samples were selected by consideration of hydrophilic and hydrophobic, such as nylon 6 and polypropylene, respectively. The laser contact angle measurement has accurate, fast and convenient method to measure contact angle, and it can be a unique method to characterize nano-fibers.

Split Ring Resonator-Based Bandstop Filter with an Enhanced Bandwidth (증가된 대역폭을 갖는 SRR 기반 대역 저지 여파기)

  • Woo, Duk-Jae;Lee, Taek-Kyung;Lee, Jae-Wook
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.21 no.5
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    • pp.544-552
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    • 2010
  • In this paper, a new method to enhance the stop bandwidth of the compact microstrip bandstop filter based on split ring resonator(SRR) was proposed. To achieve wide stop bandwidth, we incorporated the SRR within the circular etched pattern of the defected ground structure(DGS). By incorporating the SRR within the circular etched pattern, a high magnetic coupling between SRR and signal line can be achieved. The high magnetic coupling enables the proposed structure to achieve a wide stop bandwidth. To verify the feasibility of the proposed structure, the proposed bandstop filter was compared with conventional bandstop filter employing SRRs which have been etched at both sides of the signal line. Simulation and experimental results show that the proposed structure provides an enhanced stop bandwidth compared with the conventional structure.

Three-Phase Four-Wire Inverter Topology with Neutral Point Voltage Stable Module for Unbalanced Load Inhibition

  • Cai, Chunwei;An, Pufeng;Guo, Yuxing;Meng, Fangang
    • Journal of Power Electronics
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    • v.18 no.5
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    • pp.1315-1324
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    • 2018
  • A novel three-phase four-wire inverter topology is presented in this paper. This topology is equipped with a special capacitor balance grid without magnetic saturation. In response to unbalanced load and unequal split DC-link capacitors problems, a qusi-full-bridge DC/DC topology is applied in the balance grid. By using a high-frequency transformer, the energy transfer within the two split dc-link capacitors is realized. The novel topology makes the voltage across two split dc-link capacitors balanced so that the neutral point voltage ripple is inhibited. Under the condition of a stable neutral point voltage, the three-phase four-wire inverter can be equivalent to three independent single phase inverters. As a result, the three-phase inverter can produce symmetrical voltage waves with an unbalanced load. To avoid forward transformer magnetic saturation, the voltages of the primary and secondary windings are controlled to reverse once during each switching period. Furthermore, an improved mode chosen operating principle for this novel topology is designed and analyzed in detail. The simulated results verified the feasibility of this topology and an experimental inverter has been built to test the power quality produced by this topology. Finally, simulation results verify that the novel topology can effectively improve the inhibition of an inverter with a three-phase unbalanced load while decreasing the value of the split capacitor.