• Title/Summary/Keyword: Back transfer

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Experimental Study on Autoignition of Superabsorbent Polymers (고흡수성 중합물질의 자연발화에 대한 실험적 연구)

  • Jong-Man Heo;Jae-Wook Choi
    • Journal of the Society of Disaster Information
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    • v.19 no.2
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    • pp.280-291
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    • 2023
  • Purpose: As fire accidents happen at the production and storage sites of superabsorbent polymers for convenience of daily life, an experimental study was conducted to secure basic data to establish practical preventive measures against them. Method: The sample container (20cm width × 20cm length) was made into a rectangular cuboid with the heights of 3cm, 5cm, 7cm, and 14cm, respectively, to allow access to the infinite flat plane. The front and back of the container were covered with a 300-mesh stainless steel mesh for one-dimensional heat transfer. The sample container was placed in the center of the thermostatic bath, which was heated to a predetermined temperature by setting the thermostat program in advance, and it was determined to be 'ignited' when the central temperature of the sample rose by more than 20℃ above the set temperature, and "unignited" when it was maintained at an approximate value of the set temperature. Result: The critical autoignition temperature was calculated to be 217.5℃ when the height of the sample container was 3 cm, 212.5℃ when it was 5 cm, 202.5℃ when it was 7cm, and 187.5℃ when it was 14cm. The ignition induction time to reach the maximum temperature was 34hours for 3cm, 76hours for 5cm, 143hours for 7cm, and 318hours for 14cm. Conclusion: ① As the size of the container increased, the autoignition temperature decreased and the induction time to reach the maximum temperature increased. ② An apparent activation energy was calculated to be 44.92kcal/mol, with a correlation of 96.93%.

Osmoregulation Capability of Juvenile Grey Mullets (Mugil cephalus) with the Different Salinities (어린 숭어 (Mugil cephalus)의 염분별 삼투조절 능력)

  • LEE Young Choon;CHANG Young Jin;LEE Bok Kyu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.30 no.2
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    • pp.216-224
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    • 1997
  • In order to investigate the osmoregulation capability of grey mullet, Mugil cephalus with the different salinities, juvenile fish $(13.6{\pm}0.2\;TL)$ stocked in seawater (SW) were abruptly transferred to each experimental group $0\%SW(0\%_{\circ}),\;25\%SW(7.7\%_{\circ}),\;50\%SW(16.1\%_{\circ})\;and \;100\%SW(32.8\%_{\circ})$ and reared for 60 days. Blood samples were taken by the time schedule after the transfer. Plasma $Na^{+},\;K^{+},\;Cl^{-}$ and osmolality, muscle water content, and the electron microscopical observations of chloride cells were analyzed and made by the time schedule. In $100\%SW$, the maintainable levels of plasma $Na^{+},\;K^{+},\;Cl^{-}$ and osmolality were $167.1{\pm}7.7mM/l,\;9.1{\pm}2.1mM/l,\;137.8{\pm}5.6mM/l\;and\;351{\pm}18\;mOsm/kg$, respectively. These values were significantly changed at $6h\~1\;day$ after the beginning of the experiment with four different salinities. Fish from $0\%\;and\;25\%SW$ had lower osmolalities than those of fish from $50\%\;and\;100\%SW$, and showed the hyposmotic regulation pattern. At the end of the experiment (60 days after transfer), however, no significant difference was found in the concentrations of plasma $Na^{+},\;K^{+}\;and\;Cl^{-}$ among four experimental groups. Hematocrit was increased with salinity (P<0.01). After 10 days, fish from $0\%\;and\;25\%SW$ showed the hypertrophy, fusion and edema of epithelial layer in gill lamella. However, at the 15th day, epithelial layer in gill lamella was back to the normal status. On gill of fish from $0\%SW$, one apical pit held two or three chloride cells in common. Muscle water content was subsequently regulated to near the normal levels within 4 days, and there was no significant difference among four different salinities at the end of the experiment.

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2013 Records Regime Issues and Prospects for Public Records Management in Korea (한국 공공기록관리의 쟁점과 전망 2013년 기록관리체제를 위하여)

  • Ahn, Byung-Woo;Lee, Sang-min;Sim, Seong-Bo;Nam, Kyeong-Ho;Kim, Jin-Sung;O, Dong-Seok;Jeong, Tae-Young
    • The Korean Journal of Archival Studies
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    • no.34
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    • pp.3-28
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    • 2012
  • The year of 2013 is the first year that the new president takes the power and administrates the national affairs. In Korea, when the new president comes, the new administration brings big changes in the politics, economy, and society. The government management style has been changed according to the orientation and styles of the new president. Public records management is a critical and effective business tool to establish and carry out the government policies as well as an essential tool for democracy. Modern democracy is based on good governance. Creation and free use of full and accurate public records makes the good communication between the government and the public possible, and people's participation in the policy-making and surveillance of government activities for public good can work. During the present administration, communication between the president and the people was cutoff and people's participation in the national affairs have been further limited. Furthermore, in the present administration, the public records management was not regarded important, Whatever new administration comes, the year of 2013 is the time for the new administration to realize again the importance of the public records management and put it back to the normal track. Here are the major issues in the public records management to be concerned and resolved; (1) to ensure technological and institutional management of the electronic records in the government and safe transfer of the massive electronic records, (2) to establish an independent national records management and archives authority to be based on good governance, (3) to innovate the public records management in the public agencies including their agency records offices (RMO) and records management systems (RMS) (4) to establish local government archives and document local government policies and activities (5) supporting and promotion for documentation of the total society as a public service (6) expanding employment of professional records managers and archivists in the central and local governments, and standardization of professional competency and certification. In this paper, I will introduce the major issues in the public records management and suggest the policies and solutions that the Korean records professionals considered and discussed. This analysis and suggestions are the outcome of our professional considerations and discussions.

It Doesn't Taste the same from Someone Else's Plate: The Influence of Culture in Interpersonal Retail Service Evaluations (별인적반자적미도불일양(别人的盘子的味道不一样): 문화대인제령수복무평개적영향(文化对人际零售服务评价的影响))

  • Spielmann, Nathalie;Kim, Ju-Ran
    • Journal of Global Scholars of Marketing Science
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    • v.20 no.2
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    • pp.164-172
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    • 2010
  • This study reviews the influence of culture in interpersonal servicescapes by examining the restaurant retail setting. Two cultures (Canada and France) are surveyed in order to better understand their retail expectations towards interpersonal servicescapes. Using Hofstede's (1991) cultural dimensions to explain some of the differences between Canadian and French restaurant patrons, this study demonstrates a potentially interesting research avenue in the field of cross-cultural interpersonal services marketing. It demonstrates that cultural dimensions do not operate independently but interdependently. Understanding this can help retailers better explain complex service interactions between countries that may appear similar in terms of various socio-demographic features. In this exploratory research, a measure via exploratory factor analysis was developed, one that encompasses both the physical and service aspects common to interpersonal servicescape by using personality traits. This measure was tested in order to better understand the service expectations between two cultures, Canada and France. Five dimensional structures were uncovered in both cultures but with different traits and groupings. The differences between the traits uncovered and the overall Canadian and French personality structures find some explanation using Hofstede's (1991) cultural dimensions. The results of this survey point to a possible explanation as to why when services are transferred between cultures, the perceptions of them can be different and sometimes even lead to service failure. There are clearly some cultural differences between the Canadian and French consumers and their overall expectations regarding their consumption experience. Reviewing the first factor of the French and Canadian personality structures shows that the individualist/collectivist differences are apparent between the Canadian and the French cultures. The second dimension also has quite a few traits in common, five, all of which have the personal treatment aspect of the restaurant experience that a service provider would be responsible for: polite, respectful, and dedicated. Notable is that the French dimension does not include the authenticity or the hospitable aspect of the experience but includes even more features that are inherent to the personal interaction, such as charming and courteous. The third dimension of the Canadian and French structures reflects completely different expectations. Whereas the French dimension centers around energy and enthusiasm, the Canadian version is more laid-back and relaxed. There is extroversion in the French dimension to introversion in the Canadian dimension. This could be explained by differences on the Uncertainty Avoidance dimension as outlined by Hofstede (1991). The fourth dimension seems to confirm previously outlined cultural differences. Whereas Canadians, being a bit lower on uncertainty avoidance and power distance, prefer an intimate and private experience, the French continue to expect extraversion and inclusive features to their experience. The fifth dimension is in the French personality structure a clear expression of the high power distance society, where the roles of the players in the restaurant experience are clearly defined and the rules of engagement preserved. This study demonstrates that different cultures clearly do relate to different expectations regarding interpersonal services. This is apparent in the dimensions that come up in both the French and the Canadian personality structures, not only in terms of how different they are but also in with which cultural dimensions these can be explained. For interpersonal servicescapes, the use of personality traits is interesting as it allows for both physical and service features to be accounted for. Furthermore, the social component inherent to interpersonal servicescapes surfaces in most of the dimensions of the service personality structures. The quality of social exchanges is extremely important, and this even more so in cross-cultural situations, where the expec tations regarding the service experience may vary. As demonstrated by this research and using Hofstede's (1991) paradigm, not all societies will have the same expectations pertaining to the interpersonal services. Furthermore, the traditions surrounding the type of service can also have an impact on the service evaluations and differ between countries and cultures. However, using personality traits may also allow for retailers to see which service traits are common to two or more cultures where they seek to be present, and focus on these in the offering. The findings demonstrate the importance of the individualist and collectivist dimension for interpersonal servicescapes. This difference between the French and the Canadian personality structure is apparent in the most dominant dimension as well as within others. The findings are a step in explaining how retailers can transfer and then measure interpersonal services across cultures.

Monitoring of Atmospheric Aerosol using GMS-5 Satellite Remote Sensing Data (GMS-5 인공위성 원격탐사 자료를 이용한 대기 에어러솔 모니터링)

  • Lee, Kwon Ho;Kim, Jeong Eun;Kim, Young Jun;Suh, Aesuk;Ahn, Myung Hwan
    • Journal of the Korean Association of Geographic Information Studies
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    • v.5 no.2
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    • pp.1-15
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    • 2002
  • Atmospheric aerosols interact with sunlight and affect the global radiation balance that can cause climate change through direct and indirect radiative forcing. Because of the spatial and temporal uncertainty of aerosols in atmosphere, aerosol characteristics are not considered through GCMs (General Circulation Model). Therefor it is important physical and optical characteristics should be evaluated to assess climate change and radiative effect by atmospheric aerosols. In this study GMS-5 satellite data and surface measurement data were analyzed using a radiative transfer model for the Yellow Sand event of April 7~8, 2000 in order to investigate the atmospheric radiative effects of Yellow Sand aerosols, MODTRAN3 simulation results enable to inform the relation between satellite channel albedo and aerosol optical thickness(AOT). From this relation AOT was retreived from GMS-5 visible channel. The variance observations of satellite images enable remote sensing of the Yellow Sand particles. Back trajectory analysis was performed to track the air mass from the Gobi desert passing through Korean peninsular with high AOT value measured by ground based measurement. The comparison GMS-5 AOT to ground measured RSR aerosol optical depth(AOD) show that for Yellow Sand aerosols, the albedo measured over ocean surfaces can be used to obtain the aerosol optical thickness using appropriate aerosol model within an error of about 10%. In addition, LIDAR network measurements and backward trajectory model showed characteristics and appearance of Yellow Sand during Yellow Sand events. These data will be good supporting for monitoring of Yellow Sand aerosols.

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Effects of Iterative Reconstruction Algorithm, Automatic Exposure Control on Image Quality, and Radiation Dose: Phantom Experiments with Coronary CT Angiography Protocols (반복적 재구성 알고리즘과 관전류 자동 노출 조정 기법의 CT 영상 화질과 선량에 미치는 영향: 관상동맥 CT 조영 영상 프로토콜 기반의 팬텀 실험)

  • Ha, Seongmin;Jung, Sunghee;Chang, Hyuk-Jae;Park, Eun-Ah;Shim, Hackjoon
    • Progress in Medical Physics
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    • v.26 no.1
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    • pp.28-35
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    • 2015
  • In this study, we investigated the effects of an iterative reconstruction algorithm and an automatic exposure control (AEC) technique on image quality and radiation dose through phantom experiments with coronary computed tomography (CT) angiography protocols. We scanned the AAPM CT performance phantom using 320 multi-detector-row CT. At the tube voltages of 80, 100, and 120 kVp, the scanning was repeated with two settings of the AEC technique, i.e., with the target standard deviations (SD) values of 33 (the higher tube current) and 44 (the lower tube current). The scanned projection data were reconstructed also in two ways, with the filtered back projection (FBP) and with the iterative reconstruction technique (AIDR-3D). The image quality was evaluated quantitatively with the noise standard deviation, modulation transfer function, and the contrast to noise ratio (CNR). More specifically, we analyzed the influences of selection of a tube voltage and a reconstruction algorithm on tube current modulation and consequently on radiation dose. Reduction of image noise by the iterative reconstruction algorithm compared with the FBP was revealed eminently, especially with the lower tube current protocols, i.e., it was decreased by 46% and 38%, when the AEC was established with the lower dose (the target SD=44) and the higher dose (the target SD=33), respectively. As a side effect of iterative reconstruction, the spatial resolution was decreased by a degree that could not mar the remarkable gains in terms of noise reduction. Consequently, if coronary CT angiogprahy is scanned and reconstructed using both the automatic exposure control and iterative reconstruction techniques, it is anticipated that, in comparison with a conventional acquisition method, image noise can be reduced significantly with slight decrease in spatial resolution, implying clinical advantages of radiation dose reduction, still being faithful to the ALARA principle.

Surgical Treatment of Anomalous Origin of Coronary Artery from the Pulmonary Artery: Postoperative Changes of Ventricular Dimensions and Mitral Regurgitation (관상동맥-폐동맥 이상기시증(Anomalous Origin of Coronary Artery from Pulmonary Artery)의 수술적 치료: 중기 성적과 좌심실 및 승모판 기능의 변화 양상에 대한 연구)

  • Kang, Chang-Hyun;Kim, Woong-Han;Seo, Hong-Joo;Kim, Jae-Hyun;Lee, Cheul;Chang, Yoon-Hee;Hwang, Seong-Wook;Back, Man-Jong;Oh, Sam-Se;Na, Chan-Young;Han, Jae-Jin;Lee, Young-Tak;Kim, Chong-Whan
    • Journal of Chest Surgery
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    • v.37 no.1
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    • pp.19-26
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    • 2004
  • Background: The aims of this study are to verify the result of the surgical treatment of ALCAPA and to identify the postoperative changes of left ventricular dimensions and mitral regurgitation (MR), Material and Method: Fifteen patients operated on since 1985 were included in the study. The patients operated on before 1998 (n=9) showed heterogeneous properties with various surgical strategies and cardiopulmonary bypass techniques. However, six patients were operated on with the established surgical strategy since 1998; 1) Dual perfusion and dual cardioplegic solution delivery through ascending aorta and main pulmonary artery, 2) Coronary transfer by rolled-conduit made of pulmonary artery wall flap, and 3) Additional mitral valvular procedure was not peformed. Result: Median age of the study group was 6 months (1 month to 34 years). The operative methods were left subclavian artery to left coronary artery anastomosis in 1, simple ligation in 2, Takeuchi operation in 2, and coronary reimplantation in 10 patients. The mean follow up period was 5.5<5.8 years (2 months 14 years), There were one early death (6.7%) and one late death. Overall 5-year survival rate was 85.6$\pm$9.6%. The Z-value of left ventricular end-diastolic and end-systolic dimensions were 6.4$\pm$3.0 and 5.1 $\pm$3.6 preoperatively, and decreased to 1.7$\pm$ 1.9 and 0.8$\pm$ 1.6 in 3 months (p<0.05). Significant preoperative MR was identified in 6 patients (40%) and all the patients showed immediate improvement of MR within f month postoperatively. There were 3 cases of reoperation due to coronary anastomosis site stenosis and recurrence of MR. However, there was no mortality nor late reoperation in the patients operated on after 1998. Conclusion: The surgical treatment of ALCAPA showed favorable survival and early recovery of ventricular dimensions and mitral valvular function. Although long-term reintervention was required in some cases of earlier period, all the cases after 1998 showed excellent surgical outcome without long-term problem.