• Title/Summary/Keyword: Suspension Systems

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An Assessment of the Utility of Respiratory Synchronized Systems in the PET/CT Examination (PET-CT 검사 시 호흡 동조 시스템들의 유용성 평가)

  • Seong, Yong-Jun;Yoon, Seok-Hwan;Hyun, Jun-Ho;Lee, Hong-jae;Kim, Jin-Eui
    • The Korean Journal of Nuclear Medicine Technology
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    • v.21 no.1
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    • pp.34-38
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    • 2017
  • Purpose During PET/CT examinations, the movements of internal organs caused by respiration are captured in images during multiple breathing cycles, resulting in the increases in tumor size and effects on SUV. Respiratory synchronized systems were used to evaluate tumor sizes and SUV changes. Materials and Methods Biograph mCT 64 was used for the equipment, and RPM and Anzai systems were used for the respiratory synchronized systems. We used point source and micro-phantom for an experimentation. We were performed on 12 patients who had solid tumors discovered at the base of the lung or at the top of the liver from August through September 2016. The PET images of the exhalation-to-breathing state and the CT images of the post-exhalation suspension state were gained to evaluate changes in radioactivity concentration (KBq/mL), SUVmax, cylinder diameter (mm), and tumor diameter (cm) under the conventional Static, RPM, and Anzai methods. Results The result of measuring the radioactivity concentration of the point source was RPM 94% and Anzai 91% against Static, respectively. In the two cylinders of different radioactivity in the micro-phantom, the SUVmax increased to RPM 61% and 78%, and Anzai 58% and 77% against Static, whereas the cylinder diameters decreased by RPM -26% and -28%, and Anzai -28% and -26%, each respectively. Among the patients, the SUVmax increased from a minimum of RPM 8.2% to a maximum of 94.4% against Static, and from a minimum of Anzai 7.6% to a maximum of 68.3%, respectively. As for the tumor diameters, a minimum of RPM -7.6% to a maximum of -28.9% were achieved, while the Anzai fell by a minimum of -9.6% to a maximum of -27.7%, respectively. There was no significant difference discovered in the phantom study between the RPM and Anzai, yet there was a meaningful difference in the patients' tumors (P<0.05). Conclusion The respiratory synchronized systems of RPM and Anzai yielded no significant difference in the phantom study in which the respiration was executed at regular intervals. However, it was discovered that the patients had a meaningful difference for the irregular respiratory cycle and inter-system differences. Still, the respiratory synchronized systems would be useful for the accurate diagnosis and SUV measurement as the tumor decreased in size against the existing Static and the SUV increased.

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A study on the Vibration Reduction of the Commercial High-speed Train (운영 중인 고속열차의 진동저감에 관한 연구)

  • Jeon, Chang-Sung;Choi, Sunghoon
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.18 no.11
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    • pp.697-704
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    • 2017
  • This study was carried out to investigate and alleviate the vibration problem of commercial high-speed trains. First, the measurement of the carbody vibration was performed, in order to determine the vibration level of the high-speed train. The measurement result showed that the vibration level of the driver cab was higher than that of the passenger car and that the vibration became bigger toward the trailing end of the train. The vertical vibration of the driver cab and passenger car was larger than the transverse vibration, and the maximum value of the vibration in the ballast section was larger than that in the concrete section. A dynamic analysis was carried out to improve the vibration of the KTX-Sancheon train. The results of the analysis showed that it is necessary to reduce the vibration of the driver cab and both ends of the passenger cars. To reduce the vibration of the driver cab, it was recommended that the stiffness of the secondary coil spring be reduced and the damping coefficient of the secondary vertical damper be increased. It was found that the failure of the suspension system could be the origin of the vibration problem of the high-speed train. The proper management of wheel wear plays an important role in the improvement of the operation efficiency and reduction of the carbody vibration of high-speed trains, and research is underway to change the present wheel profile to increase the mileage between wheel turning.

Experiences of Ageism and "Self-Ageism" (노인차별 경험과 자기연령주의(self-ageism))

  • Kim, Juhyun;Oh, Hyein;Ju, Kyonghee
    • 한국노년학
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    • v.40 no.4
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    • pp.659-689
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    • 2020
  • This study focuses on the process of internalizing the perception of negative discrimination among elderly people who have experienced age discrimination. The grounded theory method was used to identify the age discrimination experienced by the elderly in their daily lives and to explore the consequences of such discrimination through self-ageism. According to the analysis results, the elderly respond not only to explicit discrimination but also to implicit discrimination. In this process, the stronger the pain of old age (poverty, disease, ignorance, and solitude) and the stronger the memory of failing to respond to discrimination, the higher the level of self-ageism. "Self-ageism" has internalized the negative image of the elderly, who have been discriminated against by age, resulting in disadvantages in terms of quality of life through various reject/separate/suspension actions in reality. In the presence of supportive resources such as health, institutional support, and caregivers, the elderly have room to overcome self-ageism through more active ways. However elderly people who cannot motivate themselves and they lack these resources, elderly are trapped in negative reflux caused by self-ageism and sustained a depressed and shrinking life. In this state, it is not easy to motivate themselves and make physical, cognitive, emotional and social responses. Therefore, in this analysis, we specifically noted two aspects, contextual conditions and interventional conditions, and proposed programs for synchronizing senior citizens and improving resiliency from a microscopic point of view, and argued for the need to develop systems such as supplementing welfare and health service systems related to the entire life cycle, expanding accessibility and 'age-integration' through 'Community Care', awareness improvement and anti-discrimination laws.

Anti-depressant and anti-anxiety effects of Saccharomyces cerevisiae extract and its hydrolyzed fraction (효모 추출물 SCE 및 그 분획 SCE-40의 항 우울 및 항 불안 효과)

  • Jung, Eun-Yee;Jeong, Min-Suk;Kwon, Young-Bae;Choi, Yoon-Suk;Pyun, Kwang-Ho;Kim, Ki-Won;Shim, In-Sop
    • Science of Emotion and Sensibility
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    • v.10 no.2
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    • pp.243-252
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    • 2007
  • Anti-depressant and anti-anxiety effects of Saccharomyces cerevisiae extract and its hydrolyzed fraction. The purpose of the present study was to examine the effect of Saccharomyces cerevisiae extract (SCE) and its hydrolyzed fraction (SCE-40) on depression and anxiety-related behaviors in mice. Actions of SCE and SCE-40 on serotonin, norepinephrine and GABAergic systems in the rat cerebral cortex membranes were also examined. SCE and SCE-40 significantly reduced the immobility time in the forced swimming and tail suspension test in mice. Duration time of the open arms in the elevated plus maze test was significantly increased in the SCE and SCE-40-treated groups, compared with the saline-treated control group. SCE and its fraction SCE-40 significantly inhibited serotonin and norepinephrine transporter and GABA receptor binding, compared to the saline-treated group. In addition, serotonin and norepinephrine reuptake were significantly suppressed by SCE and SCE-40. These results demonstrate that SCE and SCE-40 produce anti-depressant and anti-anxiety effects through enhancing central serotonin, norepinephrine and GABAergic transmissions. These results suggest that SCE and SCE-40 as functional food might prove to be an effective antidepressant and anti-anxiety agent.

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A Study on the Organization and Authority of the Personal Information Protection Commission (개인정보보호위원회의 조직과 권한에 관한 연구)

  • Kim, Ilhwan;Kim, Jaehyoun
    • Journal of Internet Computing and Services
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    • v.16 no.4
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    • pp.149-156
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    • 2015
  • The Personal Information Protection Commission shall be established under the direct jurisdiction of the President and shall independently perform affairs under its authority. It shall be comprised of total 15 members (5 members designated by the President, 5 members elected at the National Assembly and 5 members designated by the Chief Justice of the Supreme Court), including one minister-level Chairperson and one vice-minister-level standing member. Main functions of the Personal Information Protection Commission include deliberation and resolution of major policies and improvement of ordinances and systems related to personal information protection, coordination of opinions among public institutions in regards to the management of personal information, recommendation of improvement such as suspension of infringement by a central administrative agency, a local government and a constitutional institution, and submission of annual reports on personal information protection to the National Assembly. The function and role of the Personal Information Protection Commission regulated by the current law are insufficient in terms of independence and authorities of protection agencies compared to the international standard or level of discussion. The Commission thus cannot play a sufficient role as an independent agency for efficient protection of personal information. Therefore, there is a need for law revision that revives the purpose of the establishment of the Personal Information Protection Commission.

Virucidal Efficacy against Avian Influenza Virus of a Disinfectant Spray Containing Grapefruit Seed Extracts, Citric Acid, Malic Acid and Benzalkonium Chloride (자몽종자추출물, 구연산, 사과산 그리고 염화벤잘코늄을 주성분으로 하는 스프레이형 소독제의 조류인플루엔자바이러스에 대한 살바이러스 효과)

  • Cha, Chun-Nam;Park, Eun-Kee;Jung, Ji-Youn;Yoo, Chang-Yeol;Kim, Suk;Lee, Hu-Jang
    • Journal of Environmental Health Sciences
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    • v.42 no.4
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    • pp.266-273
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    • 2016
  • Objectives: This study evaluated the virucidal efficacy against avian influenza virus (AIV) of a disinfectant spray containing 0.25% grapefruit seed extract, 0.2% citric acid, 0.0625% malic acid and 0.0125% benzalkonium chloride. Methods: The disinfectant spray was diluted several times with hard water (HW) and organic matter (OM). Two point five mL of each diluent was added into each test tube, and 2.5 mL of AIV suspension was inserted into each test tube. After 30 minutes of virus-disinfectant contact reaction at $4^{\circ}C$, 2.5 mL of 10% inactivated fetal bovine serum was added into each test tube to neutralize the sanitizer efficacy. The neutralized solutions were serial 10-fold dilutions with phosphate buffer solution, and 0.2 mL of the diluents was injected into the allantoic cavity of five ten-day-old-chickens per dilution time. After incubation of the embryos for five days, the viability of the AIV was examined by hemagglutination titer. The valid dilution of the disinfectant spray was estimated according to the dilution time that the virus titer was inactivated more than $10^4$ 50% egg-infective dose (EID50)/mL compared with pathogen control. Results: In HW and OM conditions, the valid dilutions of the disinfectant spray against AIV were seven- and three-fold dilutions, respectively. The AIV titer of the pathogen control was more than 6.1 log10EID50/mL, and there was no embryonic toxicity. Conclusion: The present study showed that this disinfectant spray has effective virucidal activity against AIV.

In vivo Acute Toxicity of Silicon Dioxide Nanoparticle to Mice after Intraperitonial Injection (이산화규소 나노입자의 마우스 복강 내 주입에 의한 급성독성)

  • Cha, Chun-Nam;Jung, Won-Chul;Lee, Yeo-Eun;Yoo, Chang-Yeul;Kim, Gon-Sup;Kim, Eui-Kyung;Kim, Suk;Lee, Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.26 no.1
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    • pp.43-48
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    • 2011
  • For the application of nano-sized material in various fields, the evaluation of nano-sized material toxicity is important. In the present study, various concentrations of 200 nm-sized silicon dioxide nanoparticle suspension were intraperitonially injected into mice to identify the toxicity of silicon dioxide nanoparticle in vivo. In the hematological analysis of group II treated with silicon dioxide nanoparticle 100 mg/kg body weight, lymphocytes and monocytes were significantly different compared to the control group. In group III treated with silicon dioxide nanoparticle 200 mg/kg body weight, lymphocytes, monocytes and hemoglobin were significantly different compared to the control group. In blood biochemical analysis of group III, the concentration of AST, ALT, BUN, and creatinine were significantly different compared to the control group. Histopathologic examination of the kidney indicated a mild injury only in mice received 200 mg/kg silicon dioxide nanoparticle. According to the results of the present study, the significant differences in the hematological and blood biochemical analyses and abnormal histopathological findings in the mouse kidney may have been related to exposure to silicon dioxide nanoparticle.

Bactericidal Efficacy of a Disinfectant Composed of Povidone-iodine Against Clostridium Perfringens and Mycobacterium Fortuitum

  • Cha, Chun-Nam;Park, Eun-Kee;Cho, Youyoung;Yoo, Chang-Yeul;Tutkun, Engin;Kim, Suk;Lee, Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.30 no.1
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    • pp.109-114
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    • 2015
  • Clostridium perfringens (C. perfringens) and Mycobacterium fortuitum (M. fortuitum) are associated with considerable diseases in animals and human. In this study, the disinfection efficacy of a commercial disinfectant composed to povidone-iodine (PVI) was evaluated against C. perfringens and M. fortuitum. A bactericidal efficacy test by broth dilution method was used to determine the lowest effective dilution of the disinfectant following exposure to C. perfringens and M. fortuitum for 30 min at $4^{\circ}C$. The disinfectant and test bacteria were diluted with hard water (HW) or organic matter suspension (OM) according to treatment condition. On HW condition, the bactericidal activity of the disinfectant against C. perfringens and M. fortuitum was 50 and 80 fold dilutions, respectively. On OM condition, the bactericidal activity of the disinfectant against both C. perfringens and M. fortuitum was 15 fold dilutions. As the disinfectant composed to PVI possesses bactericidal efficacy against C. perfringens and M. fortuitum, the disinfectant solution can be used to control the spread of bacterial diseases.

A Study on the Velocity, the Grain Size and the Bed Depth of the Rapid Filter (급속여과지(急速濾過池)의 여과속도(濾過速度)와 여재구성(濾材構成)의 연구(硏究) -여과저항(濾過抵抗)을 중심(中心)으로-)

  • Kang, Yong Tai
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.3 no.3
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    • pp.1-7
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    • 1983
  • In spite of extensive knowledge of the surface chemistry and the transport mechanism in filtration systems, there is still insufficient understanding of the physical characteristics of suspensions and the system components. Because of this, no filtration mechanisms are mathematically generalized to the full extent. The purpose of this paper is to propose experimental equations for the filtration process. using the tracer study in filter layer. Some of results are as follows. (1) The Volume of the specific deposit (${\sigma}$) in filtration was directly measurable using the tracer study without interrupting the filtration. (2) It was also confirmed that the head loss in filtration was greatly in fluenced by the micro-air babbles. (3) The correction coefficient(f) was introduced into the Kozeny-Carman equation in order to apply it for the clogging filter media. The coefficient(f) was experimentally obtained. The total head loss of the filter media is given by next equation. $${\frac{h}{h_0}}={\frac{1}{L}}{\int}^{z=L}_{z=0}f({\sigma})g({\varepsilon}_0,{\sigma})dz$$ $$f=aexp(-b{\sigma})$$ The above equation was applicable without regard to the variation of the suspension concentration, the filter medium diameter, the filter depth, the filtration velocity, and the amount of aluminum in all continuous filtration experiments. (4) The total head loss was graphically generalized assuming mathematical filtration models I II (see fig. 7,8) (5) The total head loss was obtained from the filtration model in the field filtration conditions. (see fig. 9,10)

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Bactericidal Efficacy of a Fumigation Disinfectant Containing Paraformaldehyde Against Salmonella Typhimurium

  • Cha, Chun-Nam;Son, Song-Ee;Yoo, Chang-Yeul;Park, Eun-Kee;Jung, Ji-Youn;Kim, Suk;Lee, Hu-Jang
    • Journal of Food Hygiene and Safety
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    • v.31 no.3
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    • pp.216-221
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    • 2016
  • This study was performed to evaluate the bactericidal efficacy of a fumigation disinfectant containing 35% paraformaldehyde against Salmonella Typhimurium (S. Typhimurium). In this study, the efficacy test of a fumigant against S. Typhimurium was carried out according to French standard NF T 72-281. The S. Typhimurium working culture suspension number (N value), all bacteria numbers on the carriers exposed to the fumigant (n1, n2, and n3), the number of bacterial suspensions by the pour plate method (N1), the number of bacterial suspensions by the filter membrane method (N2), and the mean number of bacteria recovered on the control carriers (T value), were obtained from the preliminary test. In addition, the reduction number of S. Typhimurium exposed to the fumigant (d value) was calculated using the T value, the mean number of bacteria in the recovery solution (n'1) and the mean number of bacteria on carriers plated in agar (n'2). The N value was $5.5{\times}10^8$ colony forming units (CFU)/mL, and n1, n2, and n3 were higher than 0.5N1, 0.5N2 and 0.5N1, respectively. Additionally, the T value was $3.5{\times}10^6CFU/carrier$. In terms of the bactericidal effect of the fumigant, the d value was 5.25. According to the French standard for fumigants, the d value for an effective bactericidal fumigant should be greater than 5. The results indicated that the fumigant containing 35% paraformaldehyde had an efficient bactericidal activity against S. Typhimurium, and, therefore, can be used to disinfect food materials and kitchen appliances contaminated with foodborne bacteria.