• Journal of Sensor Science and Technology
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• v.13 no.2
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• pp.128-132
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• 2004

Short wave infrared (SWIR) photovoltaic devices have been fabricated from metal organic vapour phase epitaxy (MOVPE) grown n- on p- HgCdTe films on GaAs substrates. The MOVPE grown films were processed into mesa type discrete devices with wet chemical etching employed for meas delineation and ZnS surface passivatlon. ZnS was thermally evaporated from effusion cell in an ultra high vacuum (UHV) chamber. The main features of the ZnS deposited from effusion cell in UHV chamber are low fixed surface charge density, and small hysteresis. It was found that a negative flat band voltage with -0.6 V has been obtained for Metal Insulator Semiconductor (MIS) capacitor which was evaporated at $910^{\circ}C$ for 90 min. Current-Voltage (I-V) and temperature dependence of the I-V characteristics were measured in the temperature range 80 - 300 K. The Zero bias dynamic resistance-area product ($R_{0}A$) was about $7500{\Omega}-cm^{2}$ at room temperature. The physical mechanisms that dominate dark current properties in the HgCdTe photodiodes are examined by the dependence of the $R_{0}A$ product upon reciprocal temperature. From theoretical considerations and known current expressions for thermal and tunnelling process, the device is shown to be diffusion limited up to 180 K and g-r limited at temperature below this.

• The Journal of Engineering Geology
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• v.12 no.2
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• pp.203-214
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• 2002

The statistical model was introduced to satisfy various experimental condition on the sorption of heavy metals (Pb, Cu, Cd, and Zn) by bentonite. The Box-Behnken model designed statistically was applied to determine relative impact among three variables such as pH, HCO$_3$ contents and heavy metal concentrations on the sorption. The SAS program was used to obtain the statistical solution. The statistical surface response analysis indicates that initial concentration of heavy metals and pH have an important effect on the sorption, and bicarbonate is not a serious variable. The sorption capability about heavy metals of bentonite is in the order of Pb>Cu>Zn>Cd. The precipitation as hydroxyl and carbonate complexes of heavy metals was thermodynamically analyzed as major mechanism of sorption under alkaline pHs and high bicarbonate solution. It was found that there is a little difference between the model prediction on the precipitation of heavy metals and the results of batch sorption experiment. The thermodynamic data of the programs have to revise to obtain the best fit condition between the model prediction and the experimental results.

• The Korean Journal of Food And Nutrition
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• v.34 no.2
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• pp.196-206
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• 2021

The main purpose of this study was to examine the correlation between the consumption of red ginseng-based 'SSR' for 30 days and the reduction in human fatigue, blood component changes, and immune cell activity in 35 human subjects. 'SSR' is composed of zinc oxide, folic acid, and D-α-tocopherol with red ginseng as the main component. According to the protocol criteria of the study, 35 subjects who understood the purpose of the study and signed an informed consent form were selected. The fatigue survey was conducted through a questionnaire, and after taking 'SSR', a decreased tendency of physical, mental, and neurosensory fatigue was observed. In hematological analysis, no significant changes were observed in the levels of WBC, RBC, and hemoglobin; however, AST (SGOT) and ALT (SGPT) levels were statistically significantly decreased. In immunological analysis, it was observed that the proliferative effect of T cells (CD3+CD4+) was greater than that of NK cells (CD16+CD56+). The collected data were subjected to t-test analysis using the SPSS 25.0 statistical program. The result from this study proposes that 'SSR' can be used as a functional food material as it reduces human fatigue and enhances immune function.

• Journal of computational fluids engineering
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• v.12 no.2
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• pp.8-13
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• 2007

A general purpose program NUFLEX for the analysis 3-D thermo/fluid flow and pre/post processor in complex geometry has been developed, which consists of a flow solver based on FVM and GUI based pre/post processor. The solver employs a general non-orthogonal grid system with structured grid and solves laminar and turbulent flows with standard/RNG $k-{\varepsilon}$ turbulence model. In addition, NUFLEX is incorporated with various physical models, such as interfacial tracking, cavitation, MHD, melting/solidification and spray models. For the purpose of evaluation of the program and testing the applicability, many actual problems are solved and compared with the available data. Comparison of the results with that by STAR-CD or FLUENT program has been also made for the same flow configuration and grid structure to test the validity of NUFLEX.

• 한국전산유체공학회:학술대회논문집
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• 2007.04a
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• pp.87-90
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• 2007

A general purpose program NUFLEX for the analysis 3-D thermo/fluid flow and pre/post processor in complex geometry has been developed, which consists of a flow solver based on FVM and GUI based pre/post processor. The solver employs a general non-orthogonal grid system with structured grid and solves laminar and turbulent flows with standard/RNG ${\kappa}-{\varepsilon}\;SST$ turbulence model. In addition, NUFLEX is incorporated with various physical models, such as interfacial tracking, cavitation, MHD, melting/solidification and spray model. For the purpose of verification of the program and testing the applicability, many actual problems are solved and compared with the available data. Comparison of the results with that by STAR-CD or FLUENT program has been also made for the same flow configuration and grid structure to test the validity of NUFLEX.

• BMB Reports
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• v.52 no.4
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• pp.289-294
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• 2019

The present study evaluated the role of AHNAK in Bartonella henselae infection. Mice were intraperitoneally inoculated with $2{\times}10^8$ colony-forming units of B. henselae Houston-1 on day 0 and subsequently on day 10. Blood and tissue samples of the mice were collected 8 days after the final B. henselae injection. B. henselae infection in the liver of Ahnak-knockout and wild-type mice was confirmed by performing polymerase chain reaction, with Bartonella adhesion A as a marker. The proportion of B. henselae-infected cells increased in the liver of the Ahnak-knockout mice. Granulomatous lesions, inflammatory cytokine levels, and liver enzyme levels were also higher in the liver of the Ahnak-knockout mice than in the liver of the wild-type mice, indicating that Ahnak deletion accelerated B. henselae infection. The proportion of CD4+interferon-${\gamma}$ ($IFN-{\gamma}^+$) and $CD4^+$ interleukin $(IL)-4^+$ cells was significantly lower in the B. henselae-infected Ahnak-knockout mice than in the B. henselae-infected wild-type mice. In vitro stimulation with B. henselae significantly increased $IFN-{\gamma}$ and IL-4 secretion in the splenocytes obtained from the B. henselae-infected wild-type mice, but did not increase $IFN-{\gamma}$ and IL-4 secretion in the splenocytes obtained from the B. henselae-infected Ahnak-KO mice. In contrast, $IL-1{\alpha}$, $IL-1{\beta}$, IL-6, IL-10, RANTES, and tumor necrosis $factor-{\alpha}$ secretion was significantly elevated in the splenocytes obtained from both B. henselae-infected wild-type and Ahnak-knockout mice. These results indicate that Ahnak deletion promotes B. henselae infection. Impaired $IFN-{\gamma}$ and IL-4 secretion in the Ahnak-knockout mice suggests the impairment of Th1 and Th2 immunity in these mice.

• Korean Journal of Health Education and Promotion
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• v.19 no.3
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• pp.97-105
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• 2002

This study attempts to develop a program for obesity prevention and management for students in primary, middle, and high school and was carried based on the program development process as suggested by Ewles and Simnett. Data were collected from September 1st to September 30th, 2000. The study method is as follows: 1) Reviewing the present obesity control programs practiced in primary, middle, and high school (196 schools total) in metropolitan, medium-sized, and small cities, 2) Surveying obesity students'(682 students total) perception of the obesity management in their school. 3) Reviewing the annual plan for obesity in primary, middle, and high schools 4) Analyzing the educational data (CD, VIDEO) for obesity The results are as below: I. The media researched related to obesity were mainly CD and video, aimed primarily primary school students and are biased in nature. 2. The results of how to manage obesity in students: the difficulty of obesity education in the primary school, is the arousal of a sense of shame among obese students and the lack of various educational data are the most. In the middle and high schools, a lack of various educational data, and no time or lack of time were prevailing concerns. Paramount in managing obesity is weight control, as answered by majority of primary, middle, and high school students. The major problem of obesity management is the non-cooperation of children. 3. Asked whether the weight controlling aspect of health care class was helpful or not, 51.4% of primary school students, and 71.6% of middle and high school students answered not. The most popular educational method used in health care class is the computer, with a 56.4% approval rating. Most 43.5% of respondents answered that they wanted the content of obesity management program to focus on how to lose weight. Therefore, based on the results, the obesity management program is constructed to the steps of assessment, planning, implementation, and evaluation. Assessment includes administering surveys on health needs among students and their parents and physique tests. Planning includes the set-up of long term and short term educational goal and the establishment of an operation system. Implementation includes education, exercise, behavior modification, and health service programs. Evaluation includes step-by-step evaluations for obesity reduction. After this study is conducted, the following should be further researched: More practical and systematic obesity management programs should be developed for the evaluation results. In addition, it is important to develop an appropriate media for obesity management the primary, middle and high school students.

• The Korean Journal of Nuclear Medicine Technology
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• v.13 no.1
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• pp.51-56
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• 2009

Purpose: Recently, most hospitals are introducing the PACS system and use of the system continues to expand. But small-scaled PACS called MicroPACS has already been in use through open source programs. The aim of this study is to prove utility of operating a MicroPACS, as a substitute back-up device for conventional storage media like CDs and DVDs, in addition to the full-PACS already in use. This study contains the way of setting up a MicroPACS with open source programs and assessment of its storage capability, stability, compatibility and performance of operations such as "retrieve", "query". Materials and Methods: 1. To start with, we searched open source software to correspond with the following standards to establish MicroPACS, (1) It must be available in Windows Operating System. (2) It must be free ware. (3) It must be compatible with PET/CT scanner. (4) It must be easy to use. (5) It must not be limited of storage capacity. (6) It must have DICOM supporting. 2. (1) To evaluate availability of data storage, we compared the time spent to back up data in the open source software with the optical discs (CDs and DVD-RAMs), and we also compared the time needed to retrieve data with the system and with optical discs respectively. (2) To estimate work efficiency, we measured the time spent to find data in CDs, DVD-RAMs and MicroPACS. 7 technologists participated in this study. 3. In order to evaluate stability of the software, we examined whether there is a data loss during the system is maintained for a year. Comparison object; How many errors occurred in randomly selected data of 500 CDs. Result: 1. We chose the Conquest DICOM Server among 11 open source software used MySQL as a database management system. 2. (1) Comparison of back up and retrieval time (min) showed the result of the following: DVD-RAM (5.13,2.26)/Conquest DICOM Server (1.49,1.19) by GE DSTE (p<0.001), CD (6.12,3.61)/Conquest (0.82,2.23) by GE DLS (p<0.001), CD (5.88,3.25)/Conquest (1.05,2.06) by SIEMENS. (2) The wasted time (sec) to find some data is as follows: CD ($156{\pm}46$), DVD-RAM ($115{\pm}21$) and Conquest DICOM Server ($13{\pm}6$). 3. There was no data loss (0%) for a year and it was stored 12741 PET/CT studies in 1.81 TB memory. In case of CDs, On the other hand, 14 errors among 500 CDs (2.8%) is generated. Conclusions: We found that MicroPACS could be set up with the open source software and its performance was excellent. The system built with open source proved more efficient and more robust than back-up process using CDs or DVD-RAMs. We believe that the operation of the MicroPACS would be effective data storage device as long as its operators develop and systematize it.

• Korean Journal of Human Ecology
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• v.14 no.6
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• pp.961-972
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• 2005

The purpose of this study is to investigate the improvement of English proficiency of children in the ESL and EFL learning style classrooms through the experiment method. The results of this research are as follows: first, the scores of listening and speaking and the perception of alphabets in the ESL program are higher than that in the EFL program. This means that learning in the ESL style classroom is the better way to improve English skills than in the EFL style classroom, which is common in Korea. Second, there is no difference in the English listening and speaking skills and the perception of the English alphabets between the two gender groups in the ESL & EFL style classrooms. These results suggest that the target language may be used in the English classrooms by the teachers and the students with the materials, books, and equipment are English. Teachers are expected to be in charge of playing decisive roles as demonstrators of speech, models and correctors of pronunciation and providers of materials including TV, VCR, CD players, and cassette recorders, etc.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.3
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• pp.464-471
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• 2002

Author applied several engineering methodologies to classical ultrasonic nebulizer to cope with it's demerits. After several trials and errors, we got the several meaningful results. To evaluate the modified ultrasonic nebulizer for inhalation toxicology of cadmium, author used light-scattering photometer. This paper is the one part of inhalation exposure systems for inhalation toxicology study of cadmium. According to the testing conditions, source temperature 50℃ and inlet-duct band temperature 150℃, aerosol generation results for sodium chloride and cadmium chloride were as followings: Coefficients of variation(CV) of sodium chloride and cadmium chloride for repeated trials were 3.38 and 4.77 for 10g, 2.47 and 5.02 for 5g, and 4.70 and 2.98 for 2.5g. All the CVs were within 10% of acceptance variability. Count Per Minute(CPM) changes of NaCl and CdCl₂ for 5 repeated trials were similar. CPM ratios of CdCl₂/NaCl were 1.13 for 10g, 0.76 for 5g, and 1.06 for 2.5g. Relative aerosol generation of cadmium chloride to sodium chloride was the highest in 10g. Efficiency increases of 24.50% for 5g NaCl, 14.91 % for 2.5g NaCl, and 16.48% for 2.5g CdCl₂ with respect to theoretical efficiency were observed but 0.04% efficiency decrease was observed in 5g CdC₂. According to the modifications of source temperature(20, 50, 70℃) and inlet-duct band temperature(20, 50, 100, 150, 200℃), aerosol generation results for NaCl and CdCl₂ were as followings: CPM trends for each quantity excepting 10g NaCl in inlet-duct band temperature 200℃ were similar, and the highest CPM was observed in source temperature 70℃ to each inlet-duct band temperature. The highest CPMs to 10, 5, and 2.5g NaCl were observed in source temperature 70℃ and inlet-duct band temperature 20℃. Aerosol generation of cadmium chloride was increased with the higher source temperature, excepting inlet-duct band temperature 200℃. The highest CPMs for 10, 5, and 2.5g CdCl₂ were observed in source temperature 70℃ and inlet-duct band temperature 20℃, and this trend was similar to NaCl aerosol generation The highest CPMs for 10, 5, and 2.5g CdCl₂ were observed in source temperature 70℃ and inlet-duct band temperature 20℃, and this result was similar to NaCl aerosol generation. Observed efficiencies of 5 and 2.5g NaCl were similar to ifs theoretical efficiency but -3.08% efficiency decrease of 5g CdCl₂, 17.47% efficiency increase of 2.5g CdCl₂ were observed. CPM ratio of CdCl₂/NaCl of 10g was different to 5 and 2.5g, and 2.5g ratio was higher than 5g ratio. In conclusion, to get maximum aerosol generation for NaCl and CdCl₂ will be the conditions that set the appropriate inlet-duct band temperature for each materials and increase the source temperature. Sodium chloride can be used to evaluate the performance and predict the concentration for cadmium aerosol in aerosol generator and inhalation exposure system.