• Title/Summary/Keyword: current reconstruction

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High-order Reduced Radial Zernike Polynomials for Modal Reconstruction of Wavefront Aberrations in Radial Shearing Interferometers

  • Tien Dung Vu;Quang Huy Vu;Joohyung Lee
    • Current Optics and Photonics
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    • v.7 no.6
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    • pp.692-700
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    • 2023
  • We present a method for improving the accuracy of the modal wavefront reconstruction in the radial shearing interferometers (RSIs). Our approach involves expanding the reduced radial terms of Zernike polynomials to high-order, which enables more precise reconstruction of the wavefront aberrations with high-spatial frequency. We expanded the reduced polynomials up to infinite order with symbolic variables of the radius, shearing amount, and transformation matrix elements. For the simulation of the modal wavefront reconstruction, we generated a target wavefront subsequently, magnified and measured wavefronts were generated. To validate the effectiveness of the high-order Zernike polynomials, we applied both low- and high-order polynomials to the wavefront reconstruction process. Consequently, the peak-to-valley (PV) and RMS errors notably decreased with values of 0.011λ and 0.001λ, respectively, as the order of the radial Zernike polynomial increased.

Spatial and Statistical Properties of Electric Current Density in the Nonlinear Force-Free Model of Active Region 12158

  • Kang, Jihye;Magara, Tetsuya;Inoue, Satoshi
    • The Bulletin of The Korean Astronomical Society
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    • v.41 no.1
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    • pp.46.1-46.1
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    • 2016
  • The formation process of a current sheet is important for solar flare from a viewpoint of a space weather prediction. We therefore derive the temporal development of the spatial and statistical distribution of electric current density distributed in a flare-producing active region to describe the formation of a current sheet. We derive time sequence distribution of electric current density by applying a nonlinear force-free approximation reconstruction to Active Region 12158 that produces an X1.6-class flare. The time sequence maps of photospheric vector magnetic field used for reconstruction are captured by a Helioseismic and Magnetic Imager (HMI) onboard Solar Dynamic Observatory (SDO) on 10th September, 2014. The spatial distribution of electric current density in NLFFF model well reproduce observed sigmoidal structure at the preflare phase, although a layer of high current density shrinks at the postflare phase. A double power-law profile of electric current density is found in statistical analysis. This may be expected to use an indicator of the occurrence of a solar flare.

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Case Report : Latissimus Dorsi Flap for Secondary Breast Reconstruction after Partial TRAM Flap Loss (유경 횡복직근피판술 후 발생한 부분 피판괴사 및 지방괴사의 넓은등근피판을 이용한 재건 치험례)

  • Song, Jae Min;Yang, Jung Duk;Lee, Sang Yun;Jung, Ki Ho;Jung, Ho Yun;Cho, Byung Chae
    • Archives of Plastic Surgery
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    • v.36 no.1
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    • pp.75-79
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    • 2009
  • Purpose: The transverse rectus abdominis musculocutaneous(TRAM) flap is the most commonly used autogenous tissue flap for breast reconstruction. Postoperatively, partial flap loss or fat necrosis are relatively common and it may result in a smaller breast volume with marked contour irregularities. These defects are not easy to reconstruct with local tissue rearrangement or with breast implants. The current authors present the results of 2 patients who underwent Latissimus dorsi(LD) flap reconstruction to correct partial flap or fat necrosis that developed after TRAM flap breast reconstruction. Method: Case1: A 50 - year - old woman with left breast cancer visited for breast reconstruction after radical mastectomy. Initially, breast reconstruction with pedicled TRAM was performed. Postoperatively partial flap necrosis was developed. Secondary breast reconstruction using LD flap was done. Case2: A 51 - year - old woman with left breast cancer visited for breast reconstruction after radical mastectomy. Initially, breast reconstruction with pedicled TRAM was performed. Postoperatively fat necrosis was developed. Secondary breast reconstruction using LD flap was done. Results: Secondary breast reconstruction using LD flap survived completely and produce successful reconstruction. There was no significant complication in both patients. Conclusion: LD flap provides sufficient, vascularized skin and soft tissue. The flap can be molded easily to replace deficient tissue in all areas of the breast. These attributes make it an ideal candidate for salvage of the partially failed TRAM flap breast reconstructio.

Current status of and trends in post-mastectomy breast reconstruction in Korea

  • Song, Woo Jin;Kang, Sang Gue;Kim, Eun Key;Song, Seung Yong;Lee, Joon Seok;Lee, Jung Ho;Jin, Ung Sik
    • Archives of Plastic Surgery
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    • v.47 no.2
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    • pp.118-125
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    • 2020
  • Since April 2015, post-mastectomy breast reconstruction has been covered by the Korean National Health Insurance Service (NHIS). The frequency of these procedures has increased very rapidly. We analyzed data obtained from the Big Data Hub of the Health Insurance Review and Assessment Service (HIRA) and determined annual changes in the number of breast reconstruction procedures and related trends in Korea. We evaluated the numbers of mastectomy and breast reconstruction procedures performed between April 2015 and December 2018 using data from the HIRA Big Data Hub. We determined annual changes in the numbers of total, autologous, and implant breast reconstructions after NHIS coverage commenced. Data were analyzed using Microsoft Excel. The post-mastectomy breast reconstruction rate increased from 19.4% in 2015 to 53.4% in 2018. In 2015, implant reconstruction was performed in 1,366 cases and autologous reconstruction in 905 (60.1% and 39.8%, respectively); these figures increased to 3,703 and 1,570 (70.2% and 29.7%, respectively) in 2018. Free tissue transfer and deep inferior epigastric perforator flap creation were the most common autologous reconstruction procedures. For implant-based reconstructions, the rates of directto-implant and tissue-expander breast reconstructions (first stage) were similar in 2018. This study summarizes breast reconstruction trends in Korea after NHIS coverage was expanded in 2015. A significant increase over time in the post-mastectomy breast reconstruction rate was evident, with a trend toward implant-based reconstruction. Analysis of data from the HIRA Big Data Hub can be used to predict breast reconstruction trends and convey precise information to patients and physicians.

Review of Current Approaches for Implementing Metabolic Reconstruction

  • Kim, Do-Gyun;Seo, Sung-Won;Cho, Byoung-Kwan;Lohumi, Santosh;Hong, Soon-jung;Lee, Wang-Hee
    • Journal of Biosystems Engineering
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    • v.43 no.1
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    • pp.45-58
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    • 2018
  • Background: Metabolic modeling has been an essential tool in metabolic reconstruction, which has dramatically advanced in the last decades as a part of systems biology. At present, the protocol for metabolic reconstruction has been systematically established, and it provides the basis for the analysis of complex systems, which has been limited in the past. Therefore, metabolic reconstruction can be adapted to analyze agricultural systems whose metabolic data has been accumulated recently. Purpose: The aim of this review is to suggest the suitability of metabolic modeling for understanding agricultural metabolic data and to encourage the potential use of this modeling in the field of agriculture. Review: We reviewed the procedure of metabolic reconstruction using computational modeling with applicable strategies and software tools. Additionally, we presented the initial attempts of metabolic reconstruction in the field of agriculture and proposed further applications.

Current strategies for aesthetic soft tissue refinement in nasal reconstruction

  • Kim, Min Ji;Lim, Hyoseob;Park, Dong Ha
    • Archives of Craniofacial Surgery
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    • v.23 no.3
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    • pp.95-102
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    • 2022
  • The challenges of successful nasal reconstruction, which are related to the anatomical complexity of the region, have been extensively studied. Revisional operations are often required to achieve proper nasal reconstruction, with results resembling the premorbid nasal status. This is necessary to ensure the quality of life of skin cancer patients. Fundamental nasal reconstruction requires both proper soft tissue coverage and proper function. However, earlier studies in the field primarily focused on the functional aspect of nose reconstruction, although the cosmetic aspect is also an important factor to consider. In response to this need, many recent studies on nose reconstruction have proposed various refinement strategies to improve aesthetic satisfaction. Most plastic surgeons accept the nasal aesthetic subunit principle as a standard for nasal reconstruction. This review outlines the commonly used surgical refinement options and management strategies for postoperative complications based on the subunit principle. In patients with nasal defects, a proper technical strategy might help minimize revision operations and optimize the long-term results.

Performance analysis of EIT bladder monitoring system according to input current patterns (주입전류 패턴에 따른 EIT 방광 모니터링 시스템의 성능분석)

  • Han, You-Jung;Khambampati, Anil Kumar;Kim, Kyung-Youn
    • Journal of IKEEE
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    • v.23 no.1
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    • pp.164-172
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    • 2019
  • Current clinical methods for diagnosing urination disorder are invasive, expensive, and very inconvenient to perform continuous monitoring. EIT is a non-invasive technique that injects electrical current through an external electrodes and measures the induced voltage to visualize the internal electrical (impedance) characteristics, which makes it possible to monitor bladder conditions with low cost. The signal characteristics of the measured voltage data changes according to the current pattern injected through the electrode and affects reconstruction performance. In this paper, image reconstruction performance is compared and analyzed according to the injected current patterns to maximize the sensitivity to the variation of bladder size.

Breast Lipofilling: A Review of Current Practice

  • Kasem, Abdul;Wazir, Umar;Headon, Hannah;Mokbel, Kefah
    • Archives of Plastic Surgery
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    • v.42 no.2
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    • pp.126-130
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    • 2015
  • Lipofilling is a reconstructive and aesthetic technique that has recently grown in popularity and is increasingly being used in breast surgery. Previous concerns had been raised regarding its safety when used for remodelling and reconstruction of the breast; however, these concerns have since been dismissed. Over the subsequent two decades, little evidence has been found to support these early theoretical concerns, and growing numbers of proponents of the procedure are confident in its safety. Many developments and refinements in the technique have taken place in recent years, and several studies have been published regarding the safety of lipofilling in the breast. We reviewed the current literature regarding the use of different lipofilling techniques as well as the current evidence regarding the oncological safety of the procedure in patients seeking aesthetic breast enhancement and in patients requiring reconstruction after treatment for breast cancer.

Consideration of the Carrier Based Signal Injection Method in Three Shunt Sensing Inverters for Sensorless Motor Control

  • Jung, Sungho;Ha, Jung-Ik
    • Journal of Power Electronics
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    • v.16 no.5
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    • pp.1791-1801
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    • 2016
  • This paper considers a carrier based signal injection method for use in the three shunt sensing inverter (TSSI) for sensorless motor control. It also analyzes the loss according to the injection axis of the voltage signal. To remove both the phase current and rotor position sensors, a sensorless method and a phase current reconstruction method can be simultaneously considered. However, an interaction between the two methods can be incurred when both methods inject voltage signals simultaneously. In this paper, a signal injection based sensorless method with the 120° OFF Discontinuous PWM (DPWM) is implemented in a TSSI to avoid this interaction problem. Since one leg does not have a switching event for one sampling period in the 120° OFF DPWM, the switching loss is altered according to the injection axis. The switching loss in the d-axis injection case can be up to 32% larger than that in the q-axis injection case. Other losses according to the injection axis are also analyzed.

Expansion method of current reconstruction area using voltage injection in synchronous coordinates system (동기좌표계 전압주입을 이용한 3션트 PWM 인버터의 전류 복원 영역 확장 기법)

  • Choi, Dong-Min;Cho, Byung-Geuk;Cho, Younghoon
    • Proceedings of the KIPE Conference
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    • 2017.07a
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    • pp.208-209
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    • 2017
  • When controlling a three-phase inverter that drives AC motor, it is important to know the value of the current. In this case, shunt sensing methods are known as low cost and useful performance. However, for certain swithcing condition, immeasurable areas exist and it is necessary to reconstruct the current in the area. This paper proposes a reconstruction method using voltage injection in synchronous coordinates system at the area, and verify the validity of the method through simulation.

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