• Title/Summary/Keyword: Remnant life

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A study on the heat cycle aging of insulation materials in large generator stator windings (대형발전기 고정자권선 절연재료의 열 사이클에 의한 열화에 관한 연구)

  • 김희곤;박영관
    • The Transactions of the Korean Institute of Electrical Engineers
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    • v.45 no.4
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    • pp.553-557
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    • 1996
  • Heat cycle aging of insulating materials in large generator stator winding has been investigated using both on-line and off-line test methods. On this study, principally, off-line test against actual generator in service was carried out to acquire information about polarization index(PI) and dissipation factor, dissipation factor tip-up, maximum partial discharge for the purpose of remnant breakdown voltage and life assessment. It was found from the tests that both dissipation factor and maximum partial discharge decreased with the increase of operating hours and starting numbers. It was found from off-line tests that the remnant breakdown voltage had a strong relationship with both dissipation factor and maximum partial discharge the remnant breakdown voltage as a results of both operating hours and starting number and the nondestructive tests were proposed as parameters which can predict the remnant lifetime of insulating materials in large generator stator windings. (author). 8 refs., 8 figs., 2 tabs.

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Changes in Quality of Life and Related Factors in Thyroid Cancer Patients with Radioactive Iodine Remnant Ablation (방사성요오드 치료를 받는 갑상선암 환자의 삶의 질 변화와 영향요인)

  • Yoo, Seon Hee;Choi-Kwon, Smi
    • Journal of Korean Academy of Nursing
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    • v.43 no.6
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    • pp.801-811
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    • 2013
  • Purpose: To investigate changes in Quality of life (QOL) and related factors in patients with thyroid cancer undergoing Radioactive Iodine remnant ablation (RAI). Methods: Data were collected longitudinally 3 times for 6 months (2 weeks post-surgery, post RAI, 3 months post RAI) in a hospital located in Seoul. Questionnaires were used to measure levels of physical symptoms, anxiety, depression, and QOL. Ninety-eight patients with thyroid cancer who had RAI were included in the analysis. Data were analyzed using SPSS (18.0). Results: Findings for the three data collection times respectfully were: mean scores for physical symptoms, 0.53, 1.21 and 0.62, patients with depression, 47%, 36.7% and 37.7%, patients with anxiety, 18.4 %, 19.4% and 20.4%, mean scores for QOL, 7.06, 7.01 and 7.28. QOL score was highest 3 months post RAI (p=.031). In the stepwise multiple regression analysis, depression and fatigue were predicting factors for low QOL at all data collection times. Dysponia was a predicting factor for low QOL post RAI and 3 months post RAI. Conclusion: To increase QOL, it is necessary to provide information in advance regarding physical & psychological symptoms and to develop nursing intervention programs to decrease depression and fatigue.

Dielectric and Remnant Mechanical Properties Due to Cyclic Stress in PZT Ceramics (반복응력에 따른 PZT 세라믹스의 유전 및 잔류 기계적 특성)

  • 태원필;김송희
    • Journal of the Korean Ceramic Society
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    • v.31 no.8
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    • pp.829-834
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    • 1994
  • The aim of this study is to investigate the changes in dielectric properties, Young's modulus and remnant compressive strength with compressive cyclic loading in PZT of tetragonal, MPB and rhombohedral composition. Higher relative dielectric constants appeared in the poled condition than the unpoled condition for all the compositions. After poling treatment remarkably higher relative dielectric constants were observed particularly in MPB, tetragonal compositions. Until five percent of the expected fatigue life was exhausted, the dielectric constant increased with compressive cyclic stress in MPB and rhombohedral while it remained nearly constant in tetragonal. During the subsequent compressive cyclic stress, dielectric constant decreased in all the three compositions. As the compressive cyclic stress is applied the change of Young's modulus was coincided with the change of remnant compressive strength.

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Patent Omphalomesenteric Duct Remnants - Report of 4 Cases - (개방성 제장간막관 기형4예 보고)

  • Lee, Woo-Yong;Lee, Suk-Koo;Kim, Hyun-Hahk
    • Advances in pediatric surgery
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    • v.3 no.2
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    • pp.148-151
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    • 1997
  • The omphalomesenteric duct normally obliterates by the sixth week of intrauterine life. Incomplete obliteration results in various abnormalities which may be apparent in the newborn infant. These include fistula resembling ileum, a prolapsed loop of intestine through the umblicus and a fistula draining intestinal contents. The tract may contain ectopic tissue of stomach, colon or pancreas. Although this malformation should be recognizable at birth, 40 % of patients are not treated until after the first month of life. In the past 28 months since the Samsung Medical Center opened its doors to public, the authors have treated 4 cases of patent omphalomesenteric duct remnant including one case of T-shaped total prolapse of the duct and adjacent ileum. These cases will be discussed and the literature reviewed.

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Safety Margin Evaluation of Railway wheel Based on Fracture Scenarios

  • Kwon, Seok Jin;Lee, Dong Hyung;Seo, Jung Won;Kwon, Sung Tae
    • International Journal of Railway
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    • v.5 no.2
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    • pp.84-88
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    • 2012
  • Derailment due to wheel failure would cause a tremendous social and economical cost in service operation. It is necessary to evaluate quantitatively the safety with respect to high-speed train. Although the safety of railway wheel has been ensured by an regular inspection, all critical defects cannot be detected in inspection cycles and the wheel has been replaced because a defect quickly become critical for safety. Therefore, it is important to calculate quantitatively the fracture limit and remnant life of damaged railway wheel in wheel-rail system. In present paper, the critical crack size of wheel for high-speed train is simulated based on fracture scenario and the safety of wheel is evaluated.

A Study on the Remnant Forms and Effects of Big Trees in an Urban Area (도시역 거수목의 잔존형태와 그 효용성에 관한 연구)

  • 김용수;임원현
    • Journal of the Korean Institute of Landscape Architecture
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    • v.24 no.3
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    • pp.14-28
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    • 1996
  • Purposes of this study were to provide the basic information for the management policy for more preserve and refreshing Gusumok-big and old tree. Fundamental directions for the protection and application of Gusumok were suggested by comparing and analyzing present conditions and remnant forms of Gusumok as preserved tree in Kyung-ju and its function and the role of Gusumok according to the civilization and diference between past and present. The main results of the study are as follows ; There are 121 Gusumok which designated as a preserved tree in Kyung-ju. It is distributed all over the Kyung-ju city uniformly and located in the enterance or the center of a village having high interests of most of residents. in the course of a civilzation, the percintage of a loss of an urban Gusumok is higher than that of a rural Gusumok and its function is also changed so much. A modern function of Gusumok can be divided into a positive and negative one. A positive function is the offer of amenity and the place of receation, formation of culture and ragulation of micro climate. A negative function is of psycholosical and functional reversed function. having a close relation with our life, Gusumok offers an amenity place to our life to make us feel soft and comfortable as well as developes the quality of our life. Gusumok has an important meaning in mordern society in that it contibutes to our village being better to live by having a historical meaning and creating a symbolic culture and history.

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Phosphorus in the Young Supernova Remnant Cassiopeia A

  • Koo, Bon-Chul;Lee, Yong-Hyun;Moon, Dae-Sik;Yoon, Sung-Chul;Raymond, John C.
    • The Bulletin of The Korean Astronomical Society
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    • v.39 no.1
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    • pp.59.1-59.1
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    • 2014
  • Phosphorus ($^{31}P$), which is essential for life, is thought to be synthesized in massive stars and dispersed into interstellar space when these stars explode as supernovae (SNe). Here we report on near-infrared spectroscopic observations of the young SN remnant Cassiopeia A, which show that the abundance ratio of phosphorus to the major nucleosynthetic product iron ($^{56}Fe$) in SN material is up to 100 times the average ratio of the Milky Way, confirming that phosphorus is produced in SNe. The observed range is compatible with predictions from SN nucleosynthetic models but not with the scenario in which the chemical elements in the inner SN layers are completely mixed by hydrodynamic instabilities during the explosion.

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Chronic epidural hematoma evacuated through surgical treatment: a case report

  • Sin, Eui Gyu
    • Journal of Trauma and Injury
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    • v.35 no.1
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    • pp.43-45
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    • 2022
  • Epidural hematoma (EDH) can sometimes be life-threatening, although small-volume EDHs can resolve spontaneously like other intracranial hematomas. However, in rare cases, EDH can transform into a chronic form instead of disappearing. In contrast to subdural hematoma, there is no agreed-upon definition or treatment of chronic EDH. A 41-year-old male patient with acute EDH in the bilateral paravertical area due to partial rupture of the sagittal sinus was operated first, and then remnant contralateral hematoma was treated conservatively. One month after surgery, he showed hemiparesis, and brain imaging revealed chronic EDH at the location of the remnant acute hematoma. We performed surgery again to treat chronic EDH through a large craniotomy. Although many cases of EDH are self-limited, clinicians must keep in mind that some cases of EDH, especially those of venous origin and arising in young people, can become chronic and require surgical treatment.

Polycarprolactone Ultrafine Fiber Membrane Fabricated Using a Charge-reduced Electrohydrodynamic Process

  • Kim, Geun-Hyung;Yoon, Hyeon;Lee, Haeng-Nam;Park, Gil-Moon;Koh, Young-Ho
    • Macromolecular Research
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    • v.17 no.7
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    • pp.533-537
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    • 2009
  • This paper introduces a modified electro spinning system for biomedical wound-healing applications. The conventional electrospinning process requires a grounded electrode on which highly charged electro spun ultrafine fibers are deposited. Biomedical wound-healing membranes, however, require a very low charge and a low level of remnant solvent on the electrospun membrane, which the conventional process cannot provide. An electrohydrodynamic process complemented with field-controllable electrodes (an auxiliary electrode and guiding electrodes) and an air blowing system was used to produce a membrane, with a considerably reduced charge and low remnant solvent concentration compared to one fabricated using the conventional method. The membrane had a small average pore size (102 nm) and high porosity (85.1%) for prevention of bacterial contamination. In vivo tests on rats showed that these directly electro spun fibrous membranes produced using the modified electro spinning process supported the good healing of skin bums.