• Title/Summary/Keyword: damage level

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The Effects of Meta-cognition Strategy Task Training on Occupational Performance and High-Level Function of Chronic Stroke Patient with Cognitive Damage (인지손상을 동반한 만성 뇌졸중환자의 메타인지전략 과제훈련의 적용이 작업수행과 고위인지기능에 미치는 영향)

  • Han, Ga-ram;Kim, Gyu-Yong;Choi, Young-Eun;Ko, Tae-Sung
    • Journal of Korean Academy of Medicine & Therapy Science
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    • v.10 no.2
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    • pp.59-71
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    • 2018
  • Objective: The purpose of this study is to compare the effects of the CO-OP program using cognitive strategy on the satisfaction and high-level cognitive function of chronic stroke patients with cognitive impairment with the existing task-oriented approach training method. Method: The group randomly selects the experimental group and control group from 30 patients who suffer cognitive damage due to brain damage, and then randomly presents the Cognitive Orientation to daily Occupative Performance (CO-OP) Results: The results of the study showed a significant increase in patient performance and satisfaction, task performance, and high-level cognitive functions in comparison to those before training (p<).05) There was no significant difference in CNT testing in controls; Although there were no significant differences in overall CNT testing between the two groups, the COPM, AMPS tests showed a significant increase in the experimental group compared to the comparators (p <.05). Conclusion: The Cognitive Orientation to Daily Occupative Performance (CO-OP) Intervention Act, which uses meta-in strategies, was previously used. We were able to confirm that it could be a more effective intervention in task performance and high-level cognitive function than in the Meaningful Task-Specific Training Program (MTST).

Drop-weight impact damage evaluation for carbon fiber/epoxy composite laminates (탄소 섬유강화 복합재료의 중력 낙하 충격으로 인한 손상 평가)

  • Sohn, Min-Seok;Hu, Xiao-Xhi;Ki, Jang-Kyo;Hong, Soon-Hyung
    • Proceedings of the Korean Society For Composite Materials Conference
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    • 2001.05a
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    • pp.89-92
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    • 2001
  • Drop weight impact tests were performed to investigate the impact behavior of carbon fiber/epoxy composite laminates reinforced by short fibers and other interleaving materials. Characterization techniques, such as cross-sectional fractography and scanning acoustic microscopy, were employed quantitatively to assess the internal damage of some composite laminates. Scanning electron microscopy was used to observe impact damage and fracture modes on specimen fracture surfaces. The results show that composite laminates experience various types of fracture; delamination, intra-ply cracking, matrix cracking and fiber breakage depending on the interlayer materials. Among the composite laminates tested in this study, the composites reinforced by Zylon fibers showed very good impact damage resistance with medium level of damage, while the composites interleaved by poly(ethylene-co-acrylic acid) (PEEA) film is expected to deteriorate the bulk strength due to the reduction of fiber volume fraction, even though the damaged area is significantly reduced.

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Structural damage localization using spatial wavelet packet signature

  • Chang, C.C.;Sun, Z.
    • Smart Structures and Systems
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    • v.1 no.1
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    • pp.29-46
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    • 2005
  • In this study, a wavelet packet based method is proposed for identifying damage occurrence and damage location for beam-like structures. This method assumes that the displacement or the acceleration response time histories at various locations along a beam-like structure both before and after damage are available for damage assessment. These responses are processed through a proper level of wavelet packet decomposition. The wavelet packet signature (WPS) that consists of wavelet packet component signal energies is calculated. The change of the WPS curvature between the baseline state and the current state is then used to identify the locations of possible damage in the structure. Two numerical studies, one on a 15-storey shear-beam building frame and another on a simply-supported steel beam, and an experimental study on a simply-supported reinforced concrete beam are performed to validate the proposed method. Results show the WPS curvature change can be used to locate both single and sparsely-distributed multiple damages that exist in the structure. Also the accuracy of assessment does not seem to be affected by the presence of 20-15dB measurement noise. One advantage of the proposed method is that it does not require any mathematical model for the structure being monitored and hence can potentially be used for practical application.

Comparison of the Protective Effect of Antioxidant Vitamins and Fruits or Vegetable Juices on DNA Damage in Human Lymphocyte Cells Using the Comet Assay (Comet Assay를 이용한 항산화 비타민과 과일.야채즙의 인체 임파구 세포 DNA 손상 감소 효과 비교)

  • 전은재;박유경;김정신;강명희
    • Journal of Nutrition and Health
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    • v.37 no.6
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    • pp.440-447
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    • 2004
  • In this study the in vitro protective effects of several antioxidant vitamins (vitamin C, $\alpha$-tocopherol, $\beta$-carotene), fruits and vegetables (strawberry, tangerine, orange and 100% orange juice, carrot juice), on the levels of isolated human lymphocyte DNA damage was measured using Comet assay. Comet assay has been used widely to assess the level of the DNA damage in the individual cells. Lymphocytes were pre-treated for 30 minutes with antioxidant vitamins (10, 50, 100, 500 $\mu$M) or fruits$.$vegetables (10, 100, 500, 1000 $\mu$g/ml), an4 then oxidatively challenged with 100 $\mu$M $H_2O$$_2$ for 5 min at 4$^{\circ}C$. The protective effect of antioxidant vitamins against DNA damage at a concentration of 50 $\mu$M were 50% in vitamin C, 32% in $\alpha$-tocopherol, whereas, fJ-carotene showed a 55% protection at a dose as low as 10 $\mu$M. The inhibitory effects of DNA damage by strawberry, tangerine, orange, orange juices, carrot juices were 50 - 60% with wide ranges of doses. The results of the present study indicate that most the antioxidant vitamins and fruits$.$vegetables juices produced a significant reduction in oxidative DNA damage.

Effect of Burn out Print Finishing on Cellulose Fiber Damage (섬유소계 직물의 탄화날염가공이 섬유손성에 미치는 영향)

  • 신정숙;송석규
    • Journal of the Korean Society of Clothing and Textiles
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    • v.25 no.1
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    • pp.124-131
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    • 2001
  • To find out the effect of burn out print finishing for better quality of fabric, examined processing which could make less damages on the fiber because the biggest problem is remained fibers damage after burn out print finishing. Fiber damage examined to the condition of finishing material NaHSO$_4$and H$_2$SO$_4$, 3~10min., 100~13$0^{\circ}C$, glycerin. The fiber damages evaluated the break strength and the surface condition by SEM. Among satin, pile fabric which remained fiber is silk, warp knitted fabric which remained fiber is polyester, the fibers damage level were warp knitted fabric$0^{\circ}C$, glycerin and for 6 minutes by NaHSO$_4$. When carbonized by 20%. 50% and 70% to express textile design, carbonizing rate was not effect on the fiber damage very much. There was almost no damages with glycerine, and almost no damages during 3~6minutes fixation time, 10$0^{\circ}C$ steaming heat fixation by NaHSO$_4$and H$_2$SO$_4$. Without glycerine, there were damage by hydrolysis on polyesters surface and the fiver was broken by fixation time.

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Modeling of local buckling in tubular steel frames by using plastic hinges with damage

  • Inglessis, Pether;Medina, Samuel;Lopez, Alexis;Febres, Rafael;Florez-Lopez, Julio
    • Steel and Composite Structures
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    • v.2 no.1
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    • pp.21-34
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    • 2002
  • A model of the process of local buckling in tubular steel structural elements is presented. It is assumed that this degrading phenomenon can be lumped at plastic hinges. The model is therefore based on the concept of plastic hinge combined with the methods of continuum damage mechanics. The state of this new kind of inelastic hinge is characterized by two internal variables: the plastic rotation and the damage. The model is valid if only one local buckling appears in the plastic hinge region; for instance, in the case of framed structures subjected to monotonic loadings. Based on this damage model, a new finite element that can describe the development of local buckling is proposed. The element is the assemblage of an elastic beamcolumn and two inelastic hinges at its ends. The stiffness matrix, that depends on the level of damage, the yielding function and the damage evolution law of the two hinges define the new finite element. In order to verify model and finite element, several small-scale frames were tested in laboratory under monotonic loading. A lateral load at the top of the frame was applied in a stroke-controlled mode until local buckling appears and develops in several locations of the frame and its ultimate capacity was reached. These tests were simulated with the new finite element and comparison between model and test is presented and discussed.

Classification of the Types of Damage by Extracting the Changed Areas on Land Cover Maps (토지피복지도 변화지역 추출을 통한 훼손 유형분류에 관한 연구)

  • Seo, Joung-Young
    • Journal of Environmental Science International
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    • v.29 no.5
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    • pp.551-558
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    • 2020
  • This study aims to increase the ability to adapt to the ecosystem and promote a sustainable use of the natural environment, by classifying the types of damaged lands according to various factors, such as the characteristics of the target area and form, cause, and impact of damage. Moreover, the study suggests the development of evaluation categories and criteria by each type. The results obtained are as follows: first, for the assessment of damaged lands, the changed areas were identified utilizing land cover maps. Video analysis was performed to increase the accuracy, and 88 sites were obtained. Second, the types of damage were classified into ecological infrastructure and ecological environment, and the sub-factors of the cause of damage were classified into 12 factors. Third, each evaluation system for the types of damage was composed of four steps, considering each type of damage and the level of evaluators being higher than paraprofessionals. To supplement this study, it will be necessary to utilize the database of damaged lands other than the Seoul Metropolitan Area and conduct an on-site survey for verification in the future.

Optimum design of steel frame structures considering construction cost and seismic damage

  • Kaveh, A.;Fahimi-Farzam, M.;Kalateh-Ahani, M.
    • Smart Structures and Systems
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    • v.16 no.1
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    • pp.1-26
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    • 2015
  • Minimizing construction cost and reducing seismic damage are two conflicting objectives in the design of any new structure. In the present work, we try to develop a framework in order to solve the optimum performance-based design problem considering the construction cost and the seismic damage of steel moment-frame structures. The Park-Ang damage index is selected as the seismic damage measure because it is one of the most realistic measures of structural damage. The non-dominated sorting genetic algorithm (NSGA-II) is employed as the optimization algorithm to search the Pareto optimal solutions. To improve the time efficiency of the proposed framework, three simplifying strategies are adopted: first, simplified nonlinear modeling investigating minimum level of structural modeling sophistication; second, fitness approximation decreasing the number of fitness function evaluations; third, wavelet decomposition of earthquake record decreasing the number of acceleration points involved in time-history loading. The constraints of the optimization problem are considered in accordance with Federal Emergency Management Agency's (FEMA) recommended seismic design specifications. The results from numerical application of the proposed framework demonstrate the efficiency of the framework in solving the present multi-objective optimization problem.

Experimental study on acoustic emission characteristics of reinforced concrete components

  • Gu, Aijun;Luo, Ying;Xu, Baiqiang
    • Smart Structures and Systems
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    • v.16 no.1
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    • pp.67-79
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    • 2015
  • Acoustic emission analysis is an effective technique for monitoring the evolution of damage in a structure. An experimental analysis on a set of reinforced concrete beams under flexural loading was carried out. A mixed AE analysis method which used both parameter-based and signal-based techniques was presented to characterize and identify different failure mechanisms of damage, where the signal-based analysis was performed by using the Hilbert-Huang transform. The maximum instantaneous energy of typical damage events and the corresponding frequency characteristics were established, which provided a quantitative assessment of reinforced concrete beam using AE technique. In the bending tests, a "pitch-catch" system was mounted on a steel bar to assess bonding state of the steel bar in concrete. To better understand the AE behavior of bond-slip damage between steel bar and concrete, a special bond-slip test called pullout test was also performed. The results provided the basis of quantitative AE to identify both failure mechanisms and level of damages of civil engineering structures.

DNA damage repair is suppressed in porcine aged oocytes

  • Lin, Tao;Sun, Ling;Lee, Jae Eun;Kim, So Yeon;Jin, Dong Il
    • Journal of Animal Science and Technology
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    • v.63 no.5
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    • pp.984-997
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    • 2021
  • This study sought to evaluate DNA damage and repair in porcine postovulatory aged oocytes. The DNA damage response, which was assessed by H2A.X expression, increased in porcine aged oocytes over time. However, the aged oocytes exhibited a significant decrease in the expression of RAD51, which reflects the DNA damage repair capacity. Further experiments suggested that the DNA repair ability was suppressed by the downregulation of genes involved in the homologous recombination (HR) and nonhomologous end-joining (NHEJ) pathways. The expression levels of the cell cycle checkpoint genes, CHEK1 and CHEK2, were upregulated in porcine aged oocytes in response to induced DNA damage. Immunofluorescence results revealed that the expression level of H3K79me2 was significantly lower in porcine aged oocytes than in control oocytes. In addition, embryo quality was significantly reduced in aged oocytes, as assessed by measuring the cell proliferation capacity. Our results provide evidence that DNA damage is increased and the DNA repair ability is suppressed in porcine aged oocytes. These findings increase our understanding of the events that occur during postovulatory oocyte aging.