• Bulletin of the Korean Chemical Society
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• 제30권9호
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• pp.2011-2016
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• 2009

To resolve the differentiation problem of acetone and acrolein in the analysis of carbonyls by high-performance liquid chromatography (HPLC), we investigated the optimum analytical conditions for their separation. Carbonyl compounds were collected by 2,4-dinitrophenylhydrazine (DNPH)-coated cartridges. We examined the influence of three experimental variables: temperature (25, 30, 40, 50 and 60 ${^{\circ}C}$), flow rate (1.0 and 1.2 mL/min), and relative mobile phase composition (among acetonitrile, water and tetrahydrofuran). The experimental results revealed the optimum analytical condition of a flow rate of 1.2 mL/min, temperature of 32 ${^{\circ}C}$ and mobile phase composition of acetonitrile: water: tetrahydrofuran = 34 : 52.8 : 13.2. The analysis of indoor air composition indicated that acrolein and acetone comprised 11% and 42% of all aldehydes, respectively.

• 한국세라믹학회지
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• 제26권5호
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• pp.670-676
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• 1989

The PbTiO3 is well known materials having remarkable ferroelectric, piezoelectric, and pyroelectric properties. PbTiO3 thin films with a perovskite structure were successfully fabricated on titanium substrate by chemical vapor deposition. These films were characterized according to composition, crystal structure, and electrical properties. Semi-quantitative compositional analysis of the deposited films was made by Auger Electron Spectroscopy(AES). The PbTiO3 film deposited on titanium substrate at the deposition temperature 75$0^{\circ}C$, the Ti(C2H5O)4 fraction 0.15, and O2 partial pressure 0.06atm, has a columnar structure and grows with(001) preferred orientation, and has stoichiometric composition. A clear dielectric transition and offset in the dc conductivity near the transition temperature(48$0^{\circ}C$) were observed in the deposited lead titanate film.

• 한국공작기계학회논문집
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• 제15권1호
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• pp.133-137
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• 2006

Ion permeability characteristics in nano-polymer membrane structures are performed to investigate the chemical composition and characteristics of MEA(Membrane Electrolyte Assembly) which is one of the most important parts to decide the performance in PEMFC(Polymer Electrolyte Membrane Fuel Cell) system. Subsequently, the MEA manufacturing process is presented for the uniformed MEA product. In the meantime, the analysis of SEM(Scanning Electron Microscope) is carried out in order to investigate the joint aspect and chemical composition of MEA. As a result of SEM analysis, it is found that the bonded catalyst and carbon composition contain the reasonable amount to get unit cell output. It is also found that the humidification gives the better performance result slightly.

• BMB Reports
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• 제43권10호
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• pp.670-676
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• 2010

In this paper, a novel approach, ELM-PCA, is introduced for the first time to predict protein subcellular localization. Firstly, Protein Samples are represented by the pseudo amino acid composition (PseAAC). Secondly, the principal component analysis (PCA) is employed to extract essential features. Finally, the Elman Recurrent Neural Network (RNN) is used as a classifier to identify the protein sequences. The results demonstrate that the proposed approach is effective and practical.

• 한국항공운항학회지
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• 제28권2호
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• pp.71-77
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• 2020

The checklist currently used for aviation safety inspection performed by ASIs(Aviation Safety Inspectors) consists of inspection groups and multiple items, it does not have safety attribute and structured hierarchy system which required to efficiently process aviation safety analysis. On this study, categorized the domestic and foreign ASI checklist by safety attribute from ICAO recommended and presented composition of checklist for safety assurance by comparative analysis composition of domestic and foreign ASI checklist.

• 한국정밀공학회지
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• 제15권6호
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• pp.79-89
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• 1998

In determining optimal cutting condition for face milling operation, tool wear is an important factor. For the purpose of establishing the relationship between various machining factors and tool wear, cutting tests have been performed. As a result, hardness and chemical composition of workpiece material, chemical composition and grain size of cutting tool and cutting speed have been selected as machining factors. In addition, relationship between feed rate and workpiece hardness has been observed. Prior to utilizing cutting conditions recommended by ‘Machining Data Handbook(MDH)’ as a knowledge base, an analysis for the validity of the MDH has been provided. Based on this analysis, tool life criteria applied by MDH has been modified. Finally, using MDH recommended data for neural network trainning, the results from the trained neural network for optimal cutting condition for some given workpiece and cutting tool can be used as reference cutting conditions.

• 동의생리병리학회지
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• 제20권3호
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• pp.697-700
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• 2006

This study was aimed at finding out changes in body composition of obese patients, such as body weight, body fat mass and lean body mass. The subjects of this study are 33 females and 6 males who are from obesity clinic at Gunsan medical center. We measured body composition using BIA(Bioelectrical Impedence Analysis) to compare pre-treatment with post-treatment. The measured data were analyzed by paired t-test using SPSS. Differences were considered significant at P<0.05. Body weigh, body fat mass and lean body mass were reduced each by $3.76{\pm}23.41{\;}kg,{\;}2.29{\pm}1.96kg{\;}and{\;}1.59{\pm}1.38kg$ at a significant level after 4 week-treatment.

• 교육시설 논문지
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• 제20권3호
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• pp.21-28
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• 2013

Because it is now the fourth year since the first operation of the departmentalized classroom system in March 2010, a clear analysis of the conditions for the system from the investigation of the schools' operating the system is necessary. In particular, in-depth investigation and analysis are pressing, because investigation and observation of the conditions and situations for the departmentalized classroom system are not conducted continuously after creating an environment for the management of the system through a large investment. Therefore, the purpose of this study lies in building clear data on the conditions for the operation of the departmentalized classroom system in schools by visiting schools that operate the system, grasping the conditions for environmental composition, and investigating and analyzing practical use of the environment.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제7권1호
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• pp.7-14
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• 2001

The purpose of this study is to suggest the improvement directions and conditions of spacial composition according to location style of silver towns. The spacial composition of silver town used in 3 cases are analyzed according to their location(the urban type, the sub-urban type and the resort type). The points of analysis are focused on the necessary spaces and selectable spaces related to location of silver towns. In conclusion, the urban and sub-urban silver towns should have the necessary spaces and selectable spaces through analysis of the spaces in healthcare facilities near at hand. The resort silver towns should be planned to harmony the functional spaces with building shapes because they consist of various spaces.

• Bulletin of the Korean Chemical Society
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• 제8권6호
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• pp.462-465
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• 1987

The aggregation between cationic and anionic surfactants was studied by turbidimetric and nephelometric methods with emphasis on facile analysis of the surfactants and understanding of the mixed micellization. The turbidimetric titration of sodium dodecylsulfate (SDS) with cetyltrimethylammonium bromide (CTAB) or cetylpyridinium bromide (CPB) showed maximum turbidity at equimolar composition in the SDS concentration range of 0.1-0.9 mM. The nephelometric titration of the same systems extended the limit of analysis to 0.001 mM. The sodium salts of decylsulfate and sulfonate gave similar maxima, but not at equimolar composition. The coexistence of equimolar aggregates and mixed micelles were shown over broad composition range. The aggregation and mixed micellization of the anionic/cationic surfactants mixtures depended sensitively on the hydrophobic character of the surfactants.