• Journal of Powder Materials
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• v.12 no.3
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• pp.201-207
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• 2005

Nickel powders were synthesized by the hydrazine reduction of nickel chloride solution containing ammonia in DEA solutions. The size distribution of nickel powders were investigated as a function of ammonia concentration, hydrazine concentration and the mixed composition ratio of diethanolammine (DEA) and triethanolammine (TEA). Nickel powders with the size in submicron range were obtained at $185^{\circ}C$ for 45 minutes by hydrazine reduction of nickel chloride solution in DEA solutions. The hydrazine concentrations showed significant effects on the particle size and shape distribution of nickel powders under $NH_3/Ni^{2+}$ molar ratio of 2.0 condition. As the mixed volume ratio of TEA and DEA increased, nickel powders with relatively larger particle size and low agglomeration were obtained. Nickel powders with particle size in the ranged from 0.4 to $0.9\;{\mu}m$ were obtained at the 50 $vol.%$ of TEA.

• Archives of Plastic Surgery
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• v.32 no.6
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• pp.717-722
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• 2005

The authors evaluated 14 patients from July 1999 to February 2004 treated with total keloidectomy followed by postoperative radiation treatment, delivered within 24 hours or 24-36 hours after surgery. The total dose of radiation was 1200 cGy in three fractions for 4-5 days. Among the 14 patients treated, 8 patients were evaluated for following-up. The age range of these patients were from 22 to 44 years old, with the average age of 30 years. The site of keloid lesions consisted; 6 on the ear lobe, 5 on the anterior chest and 1 on the upper arm. The mean follow-up period was 29.9 months. The recurrence was evaluated with photogrammetric analysis and skin color analysis. The photogrammetric analysis was performed with planimetry for the comparison of the ratio of the reduced size to the preoperative size. The mean value of the relative size of reduction was 55% and the ratio of the ear lobes were greater than the ratio of the chests. The skin color analysis was performed with chromameter CR-300 for the analysis of color difference (E) between the surrounding normal skin and the lesion. The larger the recurred size was, similar to the original size, the larger the E value was, so the E value posses the probability of predictable objective tool of recurrence. Although verifying the effectiveness of radiation therapy following keloidectomy need more cases and long term follow-up evaluation, this therapeutic modality seems very effective in reducing the keloid size, especially in the ear lobe.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.3
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• pp.95-102
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• 2006

Recently particulate matter(PM) emission regulations are becoming more strict for diesel engines. There is increasing interest for measuring not only concentration but also size of the particles. Laser-induced incandescence (LII) has emerged as a promising technique for measuring particle volume fraction and size. In this study, the Simple Time Resolved-LII method was applied to exhaust of Ethylene diffusion flame and diesel engine exhaust for measuring soot and PM size. The particle size data from LII technique were calibrated using Field Emission Scanning Electron Microscope(FE-SEM) and Transmission Electron Microscope(TEM) photographs. In diesel engine experiments for particle size measurement, results from LII measurement are in a good agreement with those from TEM photograph, and difference between two measurements was less than 16%.

• Journal of Radiation Protection and Research
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• v.41 no.3
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• pp.222-228
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• 2016

Background: We are developing a small size dosimeter for dose estimation in particle therapies. The developed dosimeter is an optical fiber based dosimeter mounting an radiation induced luminescence material, such as an OSL or a scintillator, at a tip. These materials generally suffer from the quenching effect under high LET particle irradiation. Materials and Methods: We fabricated two types of the small size dosimeters. They used an OSL material Eu:BaFBr and a BGO scintillator. Carbon ions were irradiated into the fabricated dosimeters at Heavy Ion Medical Accelerator in Chiba (HIMAC). The small size dosimeters were set behind the water equivalent acrylic phantom. Bragg peak was observed by changing the phantom thickness. An ion chamber was also placed near the small size dosimeters as a reference. Results and Discussion: Eu:BaFBr and BGO dosimeters showed a Bragg peak at the same thickness as the ion chamber. Under high LET particle irradiation, the response of the luminescence-based small size dosimeters deteriorated compared with that of the ion chamber due to the quenching effect. We confirmed the luminescence efficiency of Eu:BaFBr and BGO decrease with the LET. The reduction coefficient of luminescence efficiency was different between the BGO and the Eu:BaFBr. The LET can be determined from the luminescence ratio between Eu:BaFBr and BGO, and the dosimeter response can be corrected. Conclusion: We evaluated the LET dependence of the luminescence efficiency of the BGO and Eu:BaFBr as the quenching effect. We propose and discuss the correction of the quenching effect using the signal intensity ratio of the both materials. Although the correction precision is not sufficient, feasibility of the proposed correction method is proved through basic experiments.

• Journal of Biosystems Engineering
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• v.32 no.3
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• pp.166-172
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• 2007

Egg quality indices are related with freshness, size of air chamber, loss of weight, and viscosity of the yolk and the protein. However, since the described quality parameters require measured in a destructive way, it is not suitable to inspect the egg quality with complete enumeration. Therefore, this study was performed to investigate the potential of image analysis method for evaluation of internal egg quality. Samples of 90 fresh eggs were collected immediately after laying and stored up to 24 days. Five eggs were randomly drawn from each storage condition (packing vs unpacking) at a regular interval and loss of weight, specific gravity and size of air chamber were measured. The image analysis for nondestructive measurement of size of air chamber was also studied. Results showed that the egg weight and gravity gradually decreased with increasing of storage days, while the size of air chamber linear increased caused by evaporation of water through the shell. A relationship a between conventional method and the image analysis method for measuring the size of air chamber was developed with the correlation coefficient of 0.928. The new finding implied that image analysis might provide a useful nondestructive tool to assess internal egg quality.

• ALGAE
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• v.31 no.4
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• pp.373-378
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• 2016

Cochlodinium polykrikoides is a red-tide forming dinoflagellate that causes significant worldwide impacts on aquaculture industries and the marine ecosystem. There have been extensive studies on managing and preventing C. polykrikoides blooms, but it has been difficult to identify an effective method to control the bloom development. There is also limited genome information on the molecular mechanisms involved in its various ecophysiology and metabolism processes. Thus, comprehensive genome information is required to better understand harmful algal blooms caused by C. polykrikoides. We estimated the C. polykrikoides genome size using flow cytometry, with detection of the fluorescence of DNA stained with propidium iodide (PI). The nuclear genome size of C. polykrikoides was 100.97 Gb, as calculated by comparing its mean fluorescence intensity (MFI) to the MFI of Mus musculus, which is 2.8 Gb. The exceptionally large genome size of C. polykrikoides might indicate its complex physiological and metabolic characteristics. Our optimized protocol for estimating the nuclear genome size of a dinoflagellate using flow cytometry with PI can be applied in studies of other marine organisms.

• Health Policy and Management
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• v.11 no.4
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• pp.109-128
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• 2001

This study was conducted to investigate the factors affecting on organizational commitment of military hospital nursing officers. For the purpose of this study, the self-administerd questionnaire survey was done with 440 military hospital nursing officers during february, 2001. The major results of the study were summarized as follows: By path analysis using LISREL 7.0, variables such as met expectations, work involvement, pay, work definiteness, positive affectivity, family support, peer support, promotion opportunity, expectations before entering a military hospital had significant positive effect on Job satisfaction in order of size, however, vertical conflict and horizontal conflict had significant negative effect in order of size. Variables such as job satisfaction, met expectations, promotion opportunity, positive affectivity, pay had significant positive direct effect on organizational commitment in order of size, however, job routinization, job opportunity had significant negative direct effect in order of size. It was found that the following variables, listed m order of size, had significant total effects on organizational commitment: job satisfaction, met expectations, positive affectivity, promotion opportunity, pay, vertical conflict, job routinization, family support, work involvement, work definiteness, job opportunity. In considering above findings, the program or plan for job satisfaction promotion, met expectations, fair promotion opportunity, adequate pay, work definiteness, solving conflict, positive affectivity promotion would be implemented to increase organizational commitment of military hospital nursing officers.

• Transactions of the Korean hydrogen and new energy society
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• v.20 no.5
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• pp.424-431
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• 2009

Treatment for water repellency on the carbon supports of GDL which composed a part of MEA has been suggested as a solution to prevent flooding. PTFE is a fluoropolymer that has hydrophobic property and a PTFE emulsion was selected as waterproof agent in this investigation. Carbon paper was coated by PTFE emulsion with different particle size of 5~500 nm and 3~$5\;{\mu}m$ as various concentration. PTFE coated carbon paper has difference in weight variation changed proportionally at PTFE concentration and coating times. Then gas permeability of the coated carbon paper with emulsion of 3~$5\;{\mu}m$ PTFE was changed vastly. Characteristics of carbon paper coated with different PTFE emulsion were analyzed by FE-SEM, FT-IR spcetroscopy and were evaluated by weight variations, gas permeability and water contact angle.

• Journal of the Korean Institute of Educational Facilities
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• v.9 no.3
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• pp.13-21
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• 2002

The new design concept for the middle school is developed as the seventh curriculum is published. However, the credible data for a plan study and spatial organization, and the type of rooms, and using area are hardly found. On this background, the purpose of this study is to provide fundamental resources for the design of middle schools and to recognize national status of plan organizations of middle schools with analizing the space and the type of rooms of collecting 150 schools' architectural plan drafted by city, province education office for 4 years(from 1997 to 2000) As a result, we know that although the class size of school is same, the area for school buildings is very diverse. Then, in order to increasing the area and to develop school buildings' quility, the meaning of standard level should be changed urgently minimum size to optimun size.

• Proceedings of the IEEK Conference
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• 2008.06a
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• pp.771-772
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• 2008

In this paper, we analyze the characterization of Mibench, an embedded system benchmark program, using simplescalar simulator. The experimental results show Mibench generally is formed by lots of integer and memory access instructions. Especially, IPC of rijndael decoding is effected by cache size largely, but IPC of CRC32 is few effected by cache size or branch predicting algorithm.