• Title/Summary/Keyword: Local repair

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Sparsity-constrained Extended Kalman Filter concept for damage localization and identification in mechanical structures

  • Ginsberg, Daniel;Fritzen, Claus-Peter;Loffeld, Otmar
    • Smart Structures and Systems
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    • v.21 no.6
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    • pp.741-749
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    • 2018
  • Structural health monitoring (SHM) systems are necessary to achieve smart predictive maintenance and repair planning as well as they lead to a safe operation of mechanical structures. In the context of vibration-based SHM the measured structural responses are employed to draw conclusions about the structural integrity. This usually leads to a mathematically illposed inverse problem which needs regularization. The restriction of the solution set of this inverse problem by using prior information about the damage properties is advisable to obtain meaningful solutions. Compared to the undamaged state typically only a few local stiffness changes occur while the other areas remain unchanged. This change can be described by a sparse damage parameter vector. Such a sparse vector can be identified by employing $L_1$-regularization techniques. This paper presents a novel framework for damage parameter identification by combining sparse solution techniques with an Extended Kalman Filter. In order to ensure sparsity of the damage parameter vector the measurement equation is expanded by an additional nonlinear $L_1$-minimizing observation. This fictive measurement equation accomplishes stability of the Extended Kalman Filter and leads to a sparse estimation. For verification, a proof-of-concept example on a quadratic aluminum plate is presented.

Modification and Repair of a Carbon Nanotube-based Device Using an Atomic Force Microscope (원자힘현미경을 이용한 탄소나노튜브소자의 턴형 및 수리)

  • Park, Ji-Yong;Kim, Yong-Sun;Oh, Young-Mu
    • Journal of the Korean Vacuum Society
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    • v.16 no.1
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    • pp.33-39
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    • 2007
  • Electrical and mechanical modifications of devices based on carbon nanotubes(CNTs) using an atomic force microscope(AFM) in the forms of cutting and reconnection of CNTs are demonstrated. In addition to the modifications, electrostatic force microscopy is used to visualize the cutting and reconnection of CNTs. In this way, AFM is shown to be a useful tool in local modifications and manipulations of CNT-based devices.

Treatments of Phyllodes Tumor in Breast and Immediate Breast Reconstruction (유방에 발생한 엽상종양의 치료 및 즉시 유방재건)

  • Kang, Tae Jo;Kim, Young Seok;Roh, Tai Suk;Yoo, Won Min;Tark, Kwan Chul;Jeong, Joon
    • Archives of Plastic Surgery
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    • v.35 no.5
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    • pp.539-544
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    • 2008
  • Purpose: There have been limited reports on breast reconstruction after excision of phyllodes tumor. This paper reports four patients who had immediate reconstruction of the breast following excision of phyllodes tumor. Methods: We retrospectively reviewed the medical records of 14 patients from March 2000 to March 2008. Clinical data were analyzed including age, presenting symptoms and signs, type of surgery and metastasis. Results: The mean age was 38.6 years. The mean follow-up period was 40.6 months. Reconstruction was performed with latissimus dorsi musculocutaneous flap in 3 patients and transverse rectus abdominis musculocutaneous flap in 1 patient. Other cases were covered with skin graft or primary repair. 2 local recurrent cases were noted. Conclusion: The breast affected by phyllodes tumor must undergo complete excision. Followed by mastectomy, immediate reconstruction of breast improved cosmetic results, and allowed a wider surgical excision margin of tumor.

A Web based Book Lending Management System using Enterprise JavaBeans (Enterprise JavaBeans를 사용한 웹기반 도서 대출 관리)

  • Seo Bong-kun;Kim Yun-ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.9 no.2
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    • pp.366-373
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    • 2005
  • In this paper, we propose the method of integrating the Book Lending Management System running either on local and web to develop Enterprise Application in distributed environment more easily and quickly using Sun's EJB based on the lava. We integrate the Book Lending Management System which is operated separately using EJB. And, by designing and implementing the Book Lending Management System separately according to its functions, it can reduce the cost of maintenance and repair. At all platforms where the Internet, Book Lending service is possible, because it provide Web based interface with JSP. Then, we can get platform independent implementation using EJB and JSP..

Depurination of dA and dG Induced by 2-bromopropane at the Physiological Condition

  • Thapa, Pritam;Sherchan, Jyoti;Karki, Radha;Jeong, Tae-Cheon;Lee, Eung-Seok
    • Biomolecules & Therapeutics
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    • v.15 no.4
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    • pp.224-229
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    • 2007
  • Depurination, the release of purine bases from nucleosides by hydrolysis of the N-glycosidic bond, gives rise to alterations of the cell genome. Although, cells have evolved mechanisms to repair these lesions, unrepaired apurinic sites have been shown to have two biological consequences: lethality and base substitution errors. 2-Bromopropane (2-BP) is used as an intermediate in the synthesis of pharmaceuticals, dyes, and other organics. In addition, 2-BP has been used as a cleaning solvent in electronics industry. But, 2-BP was found to cause reproductive and hematopoietic disorders in local workers exposed to it. We observed massive depurination after incubation of 2'-deoxyadenosine (dA) and 2'-deoxyguanosine (dG) with the excess amount 2-BP at the physiological condition (pH 7.4, $37^{\circ}C$), which were analyzed by HPLC and LC-MS/MS. In addition, time and dose response relationship of depurination in dA and dG induced by 2-BP at the physiological condition were investigated.

A Study on the Fashion Design Development Reflecting Regional Characteristic of Seongsu-dong (성수동의 지역적 특성을 반영한 패션디자인 개발)

  • Lee, Suhdo;Yum, Misun
    • Fashion & Textile Research Journal
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    • v.19 no.4
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    • pp.373-384
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    • 2017
  • This research has its significance on contributing to the establishment of sustainable fashion industry ecosystem of Seongsu area based on the creativity which is the driving force of economic growth in the 21st century. This study reviewed the major activities and processes of Seongsu-dong's regional specialized industries project and the social economic organizations's creation of fashion clusters by using specialized books, previous research, press releases such as newspapers, magazines, and the specialized internet site(www.seoul.go.kr). Also street casual-style clothes were designed based on work-wear that themed Seongsu-dong's industrial scene and social problems. The results of this study are as follows. Seongsu-dong represents the political and economic characteristics of a typical semi-industrial area in which the automobile repair, printing, textile, leather, and handmade industries are concentrated in accordance with the government's business and policy, and shows the technical characteristics through the internal complete industrial ecosystem integration of the handmade industries. In addition, social and cultural characteristics such as various local activities based on creativity are shown by social enterprises, and cultural artists. Based on the results of analyzing the regional characteristics of Seongsu-dong according to political, economic, technological, socio-cultural characteristics, eight fashion designs were made as motifs reflecting the regional characteristics of Seongsu-dong.

Adrenal Insufficiency in Patients with Rotator Cuff Tear: Prevalence, Risk Factors and Influence on Outcome

  • Kim, Jung-Han;Gwak, Heui-Chul
    • Clinics in Shoulder and Elbow
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    • v.18 no.2
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    • pp.80-85
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    • 2015
  • Background: This study measured the rate of adrenal insufficiency among rotator cuff tear patients, and determined the roles of steroid treatment and herbal medicine as specific risk factors of adrenal insufficiency. Methods: We prospectively evaluated the 53 patients who agreed to participate in the study and underwent arthroscopic rotator cuff repair due to a chronic full-thickness tear from March 2012 to September 2013. The diagnosis of adrenal insufficieny was made by rapid adrenocortical hormone test before the operation. We collected information regarding their history of steroid and herbal medicine treatment within the last 12 months. Results: The rate of adrenal insufficiency among the rotator cuff tear patients in our study was 18.9% (10 of 53 patients). Steroid treatment (p=0.034), frequency of local steroid injection (p=0.008), and herbal medicine treatment (p=0.02) showed significant association with the risk of adrenal insufficiency. Conclusions: In this study, careful taking of a patient's medical history, such as the use of steroids and herbal medicine, is important when investigating adrenal function before surgery.

Development of sewer condition assessment and rehabilitation decision-making program(SCARD) (하수관거 평가 및 정비 우선순위 의사결정도구 개발)

  • Han, Sangjong;Hwang, Hwankook
    • Journal of Korean Society of Water and Wastewater
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    • v.29 no.1
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    • pp.123-131
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    • 2015
  • A CCTV inspection method has been widely used to assess sewer condition and performance, but Korea lacks a proper decision support system for prioritizing sewer repair and rehabilitation (R&R). The objective of this paper is to introduce the results that we have developed in the Sewer Condition Assessment and Rehabilitation Decision-making (SCARD) Program using MS-EXCEL. The SCARD-Program is based on a standardized defect score for sewer structural and hydraulic assessment. Priorities are ranked based on risk scores, which are calculated by multiplying the sewer severity scores by the environmental impacts. This program is composed of three parts, which are decision-making for sewer condition and performance assessment, decision-making for sewer R&R priority assessment, and decision-making for optimal budget allocation. The SCARD-Program is useful for decision-makers, as it enables them to assess the sewer condition and to prioritize sewer R&R within the limited annual budget. In the future, this program logic will applied to the GIS-based sewer asset management system in local governments.

Hydraulic analysis of design alternatives to improve an industrial water distribution system (공업용수 배수관망시스템을 개선하기 위한 설계 대안의 수리해석)

  • Lim, Seong-Rin
    • Journal of Korean Society of Water and Wastewater
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    • v.29 no.1
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    • pp.97-106
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    • 2015
  • A CCTV inspection method has been widely used to assess sewer condition and performance, but Korea lacks a proper decision support system for prioritizing sewer repair and rehabilitation (R&R). The objective of this paper is to introduce the results that we have developed in the Sewer Condition Assessment and Rehabilitation Decision-making (SCARD) Program using MS-EXCEL. The SCARD-Program is based on a standardized defect score for sewer structural and hydraulic assessment. Priorities are ranked based on risk scores, which are calculated by multiplying the sewer severity scores by the environmental impacts. This program is composed of three parts, which are decision-making for sewer condition and performance assessment, decision-making for sewer R&R priority assessment, and decision-making for optimal budget allocation. The SCARD-Program is useful for decision-makers, as it enables them to assess the sewer condition and to prioritize sewer R&R within the limited annual budget. In the future, this program logic will applied to the GIS-based sewer asset management system in local governments.

수도권지역산업의 경쟁력우위 분석

  • 정희수
    • Journal of the Korean Regional Science Association
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    • v.11 no.1
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    • pp.1-20
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    • 1995
  • This paper studies the comparative advantage of competitive and specialized regional industries which are manufacturing, wholesale and retail trade, servies in the metropolitan area-Seoul, Inchun, Kyunggi-do of Korea, For the analysis of industries, the coefficient of specialization, the indices of competitiveness of labor and value-added, the growth rate are simultaneously examined under the criteria of the number of workers, value of shipment, value-added, This comperative synthetic analysis is different from the traditional approaches. This paper shows that the perfectly competitive advantage of specialized industries satisfying all of three criteria are 'other business related activities', 'recreational, cultural and sporting activities' in Seoul, 'machinery and outfits, n.e.c', 'retail trade, except of motor vehicles and motorcycles, repair of personal and household goods' in Inchun. We conclude that each should strategically develop the region-oriented specialized industry which has the comparative advantage. It is the reason why the concentration of industry in necessary for the leading of regional industry under the weaken local public finance. Moreover, such an industy should provide the increase of employment and income from the viewpoint of the activation of regional economy. The potential-specialized competitive industry requires the advanced structure of production under the criteria of value-added. For the development of the metropolitan area's economy, the highly advanced technology industry including computer and electronics should be induced through the loosening of metropolitan regulation. Research center(science park) supported by th private-public sector should be built for the increase of technology sector should be built for the increase of technology power of the small and medium enterprises, Also it is necessary that the small and medium enterprises strategically make the cooperative-large group in order to avoid the disadvantage from the size.

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