• Title/Summary/Keyword: Maintenance effects

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A Study on the Repair and Strengthening Effects of Epoxy Grout for the Damaged Concrete Structure (손상된 콘크리트 구조물에 에폭시수지를 이용한 보수·보강효과에 대한 연구)

  • Shin, Sung-Woo;Cho, Tai-Kwan
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.1 no.1
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    • pp.125-132
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    • 1997
  • This study was intended to investigate the effects of epoxy grout on compressive strength for damaged concrete structures. For this purpose, concrete molds were manufactured and tested for compressive strength at 28 days after water curing. Two kinds of Korea-made and one Japan-made epoxy grouts were injected into the broken concrete molds with the automatic low-pressure injecting method or the hand injecting method.

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The Effect and Influencing Mechanism of TPM Factors to Performance

  • Park, Chae-Heung
    • Journal of Korean Society for Quality Management
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    • v.30 no.4
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    • pp.154-163
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    • 2002
  • This study tries to analyze how TPM works in domestic manufacturing industry by estimating two-stage model. First stage tests the effects of five TPM-factor variables (TFV : (1) Small group activity & Autonomous maintenance, (2) Education & Training, (3) Planned maintenance, (4) improving effectiveness of each piece of facility (5) Safety & Environment) to two TPM-performance variables. Second stage tests how two TPVs affect the industry's productivity level. By combining these two stages, this study uses a model to explain how TPM, represented by TFVs, works to improve productivity via TPVs. Multivariate and univariate regression and correlation analyses were peformed. It is shown that five TFVs works in two different ways to improve the industry's productivity level. In the second stage, overall equipment effectiveness has relatively more significant effects to the productivity level.

Damage assessment of shear-type structures under varying mass effects

  • Do, Ngoan T.;Mei, Qipei;Gul, Mustafa
    • Structural Monitoring and Maintenance
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    • v.6 no.3
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    • pp.237-254
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    • 2019
  • This paper presents an improved time series based damage detection approach with experimental verifications for detection, localization, and quantification of damage in shear-type structures under varying mass effects using output-only vibration data. The proposed method can be very effective for automated monitoring of buildings to develop proactive maintenance strategies. In this method, Auto-Regressive Moving Average models with eXogenous inputs (ARMAX) are built to represent the dynamic relationship of different sensor clusters. The damage features are extracted based on the relative difference of the ARMAX model coefficients to identify the existence, location and severity of damage of stiffness and mass separately. The results from a laboratory-scale shear type structure show that different damage scenarios are revealed successfully using the approach. At the end of this paper, the methodology limitations are also discussed, especially when simultaneous occurrence of mass and stiffness damage at multiple locations.

Prediction of Bending Fatigue Life to Welding Parts of Rail on Slab Track (슬래브궤도상의 레일 용접부 피로수명 예측)

  • 김만철;김진성;한상철
    • Journal of the Korean Society for Railway
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    • v.4 no.4
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    • pp.138-146
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    • 2001
  • For the purpose of the effective maintenance of surface irregularities of rail, this paper investigates the rail service life to a bending fatigue failure of welding parts of rail on the slab track by the structures laboratory testing to derive S-N curves, a GTDAP(General Track Dynamic Analysis Program) to calculate the stresses and a modified Miner's rule to predict a fatigue life. The useful guides for maintenance of rail welded parts on the slab track are proposed in terms of a grinding period and the depth of rail surface irregularities. This study also proposed the guides for maintenance of rail welded part on the ballast track. The effects of fatigue service lives are compared one another.

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Maintenance Effect Quantification Mode by Response Surface Method (Response Surface 방법에 의한 보수보강 정량화 모델)

  • Park Seung-Hyuc;Kim Sung-Hoon;Lim Jong-Kwon;Park Kyung-Hoon;Kong Jung-Sik
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2006.04a
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    • pp.557-564
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    • 2006
  • Life-cycle performance and maintaining cost predictions are required for the effective management for bridges. In Korea, the importance of management of bridges has been recognized over the past two decades, resulting in the development of databases and various bridge management support tools by both government and private sectors. However, none of these tools has truly included the expected features of the bridge management system (EMS) for the next generation such as the quantification of the effects of maintenance interventions on bridge condition and safety. In this paper, a novel quantification process to simulate the life-cycle performance of steel box bridges has been developed. The process is based on the Response Surface method. Various performance-related variables aloe investigated to identify a set of significant design variables to construct the response surfaces.

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GROUND TRACK ACQUISITION AND MAINTENANCE MANEUVER MODELING FOR LOW-EARTH ORBIT SATELLITE

  • Lee, Byoung-Sun;Eun, Jong-Woo;Webb, Charles-E.
    • Journal of Astronomy and Space Sciences
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    • v.14 no.2
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    • pp.355-366
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    • 1997
  • This paper presents a comprehensive analytical approach for determining key maneuver parameters associated with the acquisition and maintenance of the ground track for a low-earth orbit. A livearized model relating changes in the drift rate of the ground track directly to changes in the orbital semi-major axis is also developed. The effect of terrestrial atmospheric drag on the semi-major axis is also explored, being quantified through an analytical expression for the decay rate as a function of density. The non-singular Lagrange planetary equations, further simplified for nearly circular orbits, provide the desired relationships between the corrective in-plane impulsive velocity increments and the corresponding effects on the orbit elements. The resulting solution strategy offers excellent insight into the dynamics affecting the timing, magnitude, and frequency of these maneuvers. Simulations are executed for the ground track acquisition and maintenance maneuver as a pre-flight planning and analysis.

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Determination of Maintenance Factor for Freeway Lighting Luminaires According Traffic Volume (교통량을 고려한 고속도로 조명기구의 보수율 산정법)

  • 여인선
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.12 no.2
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    • pp.1-6
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    • 1998
  • It is required to determine proper values for the maintenance factor according to traffic volume in the freeway lighting design. This paper presents a simple method to seperate of the effect of surrounding environment and that of traffic volume, which is based on the IESNA treatment with additional assumptions on their effects. Furthermore, it is found that prevailing concept for the maintenance factor does not necessarily yield a proper value for light loss factor, so that an additional factor of 0.9 should be included as an equipment factor.factor.

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Tankyrase: Function and Tankyrase Inhibitor in Cancer

  • Kim, Mi Kyung
    • Biomedical Science Letters
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    • v.24 no.3
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    • pp.150-156
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    • 2018
  • Tankyrases are multifunctional poly (ADP-ribose) polymerases that regulate a variety of cellular processes including WNT signaling, telomere maintenance, regulation of mitosis, and many others. Tankyrases interact with target proteins and regulate their interactions and stability through poly (ADP-ribosyl) ation. In addition to their roles in telomere maintenance and regulation of mitosis, tankyrase proteins regulate tumor suppressors such as AXIN, PTEN, and AMOT. Therefore, tankyrases can be effective targets for cancer treatment. Tankyrase inhibitors could affect a variety of pathways that are carcinogenic (essential for the unlimited proliferation of human cancer cells), including WNT, AKT, YAP, telomere maintenance, and regulation of mitosis. Recently, new aspects of the function and mechanism of tankyrases have been reported and several tankyrase inhibitors have been identified. Also, it has been proposed that the combination of conventional chemotherapy agents with tankyrase inhibitors may have synergistic anti-cancer effects. Based on this, it is expected that more advanced and improved tankyrase inhibitors will be developed, enabling new therapeutic strategies against cancer and other tankyrase linked diseases. This review discusses tankyrase function and the role of tankyrase inhibitors in the treatment of cancer.

Is the Peak-Affect Important in Fast Processing of Visual Images in Printed Ads?: A Comparative Study on the Affect Integration Theories

  • Bu, Kyunghee;Lee, Luri
    • Asia Marketing Journal
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    • v.24 no.3
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    • pp.96-108
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    • 2022
  • This study investigates how affects elicited by visual images in print ads are integrated to form a liking for the ads. Assuming a sequential rather than simultaneous processing of still-cut images, we adopt the 'think-aloud' method to capture consumers' spontaneous responses to visual images. We hypothesize that not only would consumers show mixed affects toward a still-cut visual image but that they would also integrate their serial affects heuristically rather than simply averaging the affects as suggested by the compensatory hypothesis. By comparing the effects of two contradictory affect integration hypotheses (i.e., peak-affect and mood-maintenance) with compensatory integration, using a single regression model, we found that peak-negative along with mood maintenance integration of serial affects for a print ad works best in the formation of ad liking. The results also support our initial premise that people can have mixed valence even toward a still-cut ad.

Moderating Effects and Maintenance of Lung Cancer Cellular Immune Functions by CIK Cell Therapy

  • Jin, Cong-Guo;Chen, Xiao-Qun;Li, Jia;Wu, Zhi-Pin;Liu, Xin;Wang, Xi-Cai
    • Asian Pacific Journal of Cancer Prevention
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    • v.14 no.6
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    • pp.3587-3592
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    • 2013
  • Aims: To study the CIK cell treatment effects on regulation of cellular immune function disorders in patients with lung cancer, and to analyze the time characteristics. Methods: Cellular immune function was assessed by FCM, and patients with functional disorders were randomly divided into two groups, one given CIK cell therapy within 18 months (5 courses) and the other the controls, which were followed up for 1 year with cellular immune functions tested once a month. Results: There were 5 types of cellular immunity, 4 of which are disorders; after CIK treatment, the improvement rate of the 4 groups were 79.1%, 70.8%, 76.0% and 70.0%, intergroup differences not being statistically significant (P=0.675), all significantly higher than in the control group (P=0.000). The median maintenance times for the 4 groups were 10.4 months (9.76-11.04), 8.4 months (7.86-8.94), 9.8 months (9.20-10.4) and 7.9 months (6.25-9.55), respectively. Conclusions: CIK cells were able to improve the immune functions of patients with lung cancer, the rate of improvement and maintenance time being related to the immune function before the treatment and CIK-cell-therapy courses.