• Title/Summary/Keyword: SF1

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Electrical Breakdown Characteristics of Composite Insulation Composed of Epoxy Resins with N2, Dry-air in Non-uniform Field (불평등 전계 시 에폭시와 N2, dry-air 혼합절연체의 절연파괴특성)

  • Jung, Hae-Eun;Park, Seong-Hee;Kang, Seong-Hwa;Lim, Kee-Jo
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2007.06a
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    • pp.462-463
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    • 2007
  • SF6 widely used as insulating gas is rising as the environment problem. For decreasing this greenhouse gas, electrical breakdown characteristics of composite insulation composed of epoxy resins with N2, air are studied in non-uniform field. The gap of needle to plane was 3mm, 5mm. The pressure of air, nitrogen was varied within the range of 0.1~0.6MPa. The thickness of a needle is 1mm and the curvature radius of the end of needle is 100um. The diameter of a plane made of the stainless steel is 50mm. As a result of the experiment, the breakdown voltage is increased about 3 times when epoxy resins is composited. The thickness of epoxy resins filled opposite to electrode concentrated electric field weakly influences on breakdown voltage.

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Electrical Breakdown Characteristics of Epoxy and dry-air Composite Insulation (에폭시와 dry-air 혼합절연물의 절연파괴특성)

  • Jung, Hae-Eun;Oh, Jin-Heon;Lim, Jong-Nam;Kang, Seong-Hwa;Lim, Kee-Jo
    • Proceedings of the KIEE Conference
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    • 2007.07a
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    • pp.1389-1390
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    • 2007
  • SF6 gas used widely as insulating component is rising as the environment problem. Electrical breakdown characteristics of epoxy and dry-air composite insulation was investigated on thickness of epoxy and pressure of dry-air under non-uniform field. The gap of needle to plane was from 2mm to 5mm. The pressure of dry-air was varied within the range of $0.1{\sim}0.6$ MPa. The thickness of a needle was 1mm and the curvature radius of a needle end was 100um. The diameter of a plane made of the stainless steel was 50mm. As a result of the experiment, breakdown voltage was increased about 3 times when epoxy was used. The impact that the thickness of epoxy influences on breakdown voltage was poor. It needs suitable thickness computation because the insulating gap of the gas is short as epoxy thickness increases.

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Factors Influencing Quality of Life and Its Measurements in Patients with Hypertension: A Systematic Review (고혈압 환자의 삶의 질 영향요인 및 측정도구에 대한 체계적 문헌고찰)

  • Chang, Sun Ju;Jang, Sun Joo;Lee, Seung Hee;Lee, Hyun Ok
    • Journal of muscle and joint health
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    • v.24 no.1
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    • pp.24-36
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    • 2017
  • Purpose: The purpose of the study was to comprehensively explore the factors influencing quality of life and its measurements in patients with hypertension. Methods: Based on the PRISMA statement and NECA systematic literature review guideline, a systematic literature review was conducted in this study. To search studies related to quality of life in patients with hypertension, multiple electronic databases were used using a combination of key words 'hypertension' and 'quality of life'. Throughout this process, a total of 983 studies were identified. Then, the second selection processes and quality assessment were conducted by four investigators independently. Finally, a total of 19 studies were included for the analysis. Results: Results showed that quality of life was focused on the health-related quality of life, and the SF-36 was one of the most frequently used measurements. The factors influencing quality of life were categorized into sociodemographic, health-related, health behavioral, and psychosocial variables. Conclusion: Researchers need to consider these multiple factors to promote quality of life in patients with hypertension.

Voice Recognition Sensor Driven Elevator for High-rise Vertical Shift (동굴관광용 고층수직이동 승강기의 긴급 음성구동 제어)

  • Choi, Byong-Seob;Kang, Tae-Hyun;Yun, Yeo-Hoon;Jang, Hoon-Gyou;Soh, Dea-Wha
    • Journal of the Speleological Society of Korea
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    • no.88
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    • pp.1-7
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    • 2008
  • Recently, it is one of very interest technology of Human Computer Interaction(HCI). Nowadays, it is easy to find out that, for example, inside SF movies people has talking to computer. However, there are difference between CPU language and ours. So, we focus on connecting to CPU. For 30 years many scientists experienced in that technology. But it is really difficult. Our project goal is making that CPU could understand human voice. First of all the signal through a voice sensor will move to BCD (binary code). That elevator helps out people who wants to move up and down. This product's point is related with people's safety. Using a PWM for motor control by ATmega16, we choose a DC motor to drive it because of making a regular speed elevator. Furthermore, using a voice identification module the elevator driven by voice sensor could operate well up and down perfectly from 1st to 10th floor by PWM control with ATmega16. And, it will be clearly useful for high-rise vertical shift with voice recognition sensor driven.

Copper neutron transport libraries validation by means of a 252Cf standard neutron source

  • Schulc, Martin;Kostal, Michal;Novak, Evzen;Simon, Jan
    • Nuclear Engineering and Technology
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    • v.53 no.10
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    • pp.3151-3157
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    • 2021
  • Copper is an important structural material in various nuclear energy applications, therefore the correct knowledge of copper cross sections is crucial. The presented paper deals with a validation of different copper transport libraries by means of activation of selected samples. An intense 252Cf(sf) source with a reference neutron spectrum was used as a neutron source. After irradiation, the samples were measured using a high purity germanium detector and the dosimeter reaction rates were inferred. These experimental data were compared with MCNP6 calculations using CENDL-3.1, JENDL-4.0, ENDF/B-VII.1, ENDF/B-VIII.0, JEFF-3.2 and JEFF-3.3 evaluated Cu transport libraries. The experiment specifically focuses on 58Ni(n,p)58Co, 93Nb(n,2n)92mNb, 197Au(n,g)198Au and 55Mn(n,g)56Mn dosimetry reactions. Evaluated activation cross sections of these dosimetric reactions were taken from the IRDFF-II library. The best library performance depends on the energy region of interest.

Antimicrobial Properties of Knit made with PET and Ion Exchange Zeolite Nanocomposite Spun Yarn (PET와 이온교환 Zeolite 나노 복합 방적사로 제조한 니트의 항균성)

  • Jeon, Yongwook;Park, Youngmi
    • Textile Coloration and Finishing
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    • v.33 no.1
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    • pp.24-30
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    • 2021
  • In this study, PET containing 3% silver ion-exchange zeolite was mixed with cotton in a ratio of 6:4 to prepare a spun yarn to evaluate the tensile strength, absorption speed, absorption rate, antibacterial property, and the efficiency of deodorization. As a result, the following conclusions were obtained. First, it can be confirmed that silver ion exchange zeolite is evenly distributed inside and on the surface of the antimicrobial PET-SF through SEM. It was found that the tensile strength between the CVC sample mixed with silver ion zeolite PET and cotton and the normal cotton 100% sample was slightly lower in the CVC sample. Although the absorption speed and water absorption rate were measured to find out the moisture characteristics, it was confirmed that there was no significant difference. The contact angle was slightly larger in the antimicrobial CVC sample, but the time it took for the moisture to completely penetrate into the knit fabric was 0.85 seconds. In addition, it was found that out of the total mixing ratio, 40% of antibacterial PET was spun with regular cotton to produce yarn, which had an excellent bacteria reduction rate of 99.9% and a deodorization efficiency of 85%.

Feasibility study of deep learning based radiosensitivity prediction model of National Cancer Institute-60 cell lines using gene expression

  • Kim, Euidam;Chung, Yoonsun
    • Nuclear Engineering and Technology
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    • v.54 no.4
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    • pp.1439-1448
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    • 2022
  • Background: We investigated the feasibility of in vitro radiosensitivity prediction with gene expression using deep learning. Methods: A microarray gene expression of the National Cancer Institute-60 (NCI-60) panel was acquired from the Gene Expression Omnibus. The clonogenic surviving fractions at an absorbed dose of 2 Gy (SF2) from previous publications were used to measure in vitro radiosensitivity. The radiosensitivity prediction model was based on the convolutional neural network. The 6-fold cross-validation (CV) was applied to train and validate the model. Then, the leave-one-out cross-validation (LOOCV) was applied by using the large-errored samples as a validation set, to determine whether the error was from the high bias of the folded CV. The criteria for correct prediction were defined as an absolute error<0.01 or a relative error<10%. Results: Of the 174 triplicated samples of NCI-60, 171 samples were correctly predicted with the folded CV. Through an additional LOOCV, one more sample was correctly predicted, representing a prediction accuracy of 98.85% (172 out of 174 samples). The average relative error and absolute errors of 172 correctly predicted samples were 1.351±1.875% and 0.00596±0.00638, respectively. Conclusion: We demonstrated the feasibility of a deep learning-based in vitro radiosensitivity prediction using gene expression.

Application of the Life Cycle Assessment Methodology to Rice Cultivation in Relation to Fertilization (시비방법별 벼 재배에 따른 전과정평가 방법을 적용한 환경영향 평가)

  • Shin, Joung-Du;Lim, Dong-Kyu;Kim, Gun-Yeob;Park, Mun-Hee;Koh, Mun-Hwan;Eom, Ki-Cheol
    • Korean Journal of Environmental Agriculture
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    • v.22 no.1
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    • pp.41-46
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    • 2003
  • The suitability of the life Cycle Assessment (LCA) methodology to analyze the environmental impact of rice cultivation with different fertilizing systems is investigated. The arst part of an LCA is an inventory of parameters used and emissions released due to the system under investigation. In the following step, the Life Cycle Impact Assessment the inventory data were analyzed and aggregated in order to finally get one index representing the total environmental burden. For the life Cycle Impact Assessment (LCIA) the Eco-indicator 95 method has been chosen because this is well documented and regularly applied impact assessment method. The resulting index is called Eco-indicator value. The higher the Eco-indicator value the stronger is the total environmental impact of an analyzed fertilizing system. The rice field experiment conducted in middle parts of korea was chosen as an example for the life cycle impact analysis. In this experiment the treatments were consisted of none fertilizer plot (NF), standard fertilizer plot (SF) applied chemical fertilizers based on soil chemical analysis before rice transplanting, and efflux fertilized plot (EF) applied with pig wastes fermented as the same rates of SF plot as basis on total nitrogen content. The obtained Eco-indicator values were clearly different among the treatments in the rice trial. The total Eco-indicator values for SF and EF have been observed 58 and 38% relative to the NF, respectively. For all the treatments the environmental effects of eutrophication contributed most to the total Eco-indicator value. The results appeared that the LCA methodology is basically suitable to assess the environmental impact associated with different fertilizer applications for rice cultivation. A comparative analysis of the fertilizing system's contribution to global warming and eutrophication is possible.

A Study of the Depressive Symptoms and the Quality of Life in Patients with Breast Cancer in a University Hospital (일 대학병원 유방암 환자의 우울증상과 삶의 질)

  • Jang, Seung-Ho;Lee, Dae-Bo;Choi, Un Jong;Lee, Kwang-Man;Lee, Sang-Yeol
    • Korean Journal of Psychosomatic Medicine
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    • v.21 no.1
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    • pp.11-17
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    • 2013
  • Objectives : This study was designed to investigate the prevalence of depressive symptoms in patients with breast cancer and to identify demographic variables and clinical characteristics impact on depressive symptoms and health related quality of life in patients with breast cancer in a university hospital. Methods : Fourty-one patients with breast cancer were selected, who had visited the department of General surgery of the Wonkwang University hospital with a diagnosis of breast cancer regularly during the period November, 2010-May, 2011. All of subjects were evaluated for the depression, anxiety and the health related quality of life with Beck Depression Inventory(BDI), anxiety subscale of Personality Assessment Inventory(PAI) and Short-Form 36 Health Survey-Korean version(SF-36-K). Patients were divided into depressive symptoms and non-depressive symptoms group according to the BDI score. We compared SF-36-K between two groups, and analized multiple regression with depression and health related quality of life as criterion variables and demographic and clinical characteristics. Results : The prevalence of depression in patients with breast cancer in a University hospital was 36.4%. Compared to the non-depression, depressed patients with breast cancer appeared significantly lower mean scores on six subscales in SF-36-K : Physical function(p<.01), Role-physical(p<.001), General health(p<.05), Social function(p<.001), Role-emotional(p<.001) and Mental health(p<.001). But there was no significant difference between two groups in Vitality and Bodily pain. Anxiety, level of education and presence of enforcement of chemotherapy(63.6%) were significant explanation variables for depressive symptoms. And type of surgery and age(55.8%) were significant explanation variables for health related quality of life. Conclusions : The prevalence of depressive symptoms in patients with breast cancer in a University hospital was 36%. The depressive symptoms had not only negative impact on the health related quality of life but also important explanation variable for health related quality of life. These results suggest that depressive symptoms in patients with breast cancer should be evaluated and treated for improving patient's health related quality of life.

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Reliability and Validity of the Fatigue Severity Scale among University Student in South Korea (대학교 재학생에서 Fatigue Severity Scale의 신뢰도 및 타당도 연구)

  • Lee, Junghyun H.;Jeong, Hyeonseok S.;Lim, Soo Mee;Cho, Han Byul;Ma, Ji-Young;Ko, Eun;Im, Jooyeon J.;Lee, Sun Hea;Bae, Sujin;Lee, Yu-Jin;Lyoo, In Kyoon;Jeong, Do-Un
    • Korean Journal of Biological Psychiatry
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    • v.20 no.1
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    • pp.6-11
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    • 2013
  • Objectives There are only a limited number of studies on instruments assessing fatigue in university students, although fatigue exerts negative influences on their health and academic performances and fatigue-related complaints are more frequently reported in young adults than middle-aged adults. The aim of this study was to validate the 9-item Fatigue Severity Scale (FSS) among university students including both undergraduate and graduate students in South Korea. Methods A total of 176 university students completed a battery of self-report questionnaires, including the FSS, the Brief Fatigue Inventory (BFI), the Beck Depression Inventory-II (BDI-II), the Beck Anxiety Inventory (BAI), the Medical Outcomes Study Short Form 36 version 2 (MOS-SF36v2), and the Inclusion of Community in the Self Scale (ICS). The data were collected from February of 2012 to June of 2012. The reliability, convergent validity, divergent validity, and exploratory factor analyses were conducted to assess psychometric properties of the FSS. Results The mean FSS score was 3.20 (standard deviation = 1.43). The FSS demonstrated an excellent internal consistency (Cronbach's ${\alpha}$ = 0.93) and item-total correlations ranged from 0.56 to 0.90. Correlations of the FSS with the BFI (r = 0.71, p < 0.01), BDI-II (r = 0.54, p < 0.01), BAI (r = 0.46, p < 0.01), MOS-SF36v2 physical component summary (r = -0.28, p < 0.01), MOS-SF36v2 mental component summary (r = -0.55, p < 0.01), and ICS (Spearman's rho = -0.07, p = 0.33) showed acceptable convergent and divergent validity. Exploratory factor analysis defined one underlying factor (eigenvalue = 5.67) that explained 93.50% of the total variance. Conclusions To the best of our knowledge, this is the first study to investigate reliability and validity of the FSS in university students. The FSS exhibits good psychometric properties for evaluation of fatigue among university students in South Korea. Since the FSS is easy to administer, score, and interpret, it could be a useful tool in research and practice for assessing fatigue among university students.