• Journal of Nutrition and Health
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• 제26권1호
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• pp.67-75
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• 1993

Folate and iron nutrition was studied in a total of 122 pregnant, lactaging, and non-pregant, non-lactating Korean women, Serum folate levels were determined microbiologically using Lactobacillus casei(ATCC 7469), and serum iron levels was analyzed colormetrically. The average folate values of pregnant and lactating women were 5.42ng/ml and 4.14ng/ml, which were significantly lower than that of the non-pregnant, non-lactating women(7.06ng/ml). More than 1/3 of the total subjects were found to have serum folate levels lower than 3ng/ml, at which folate nutrition status can be considered inadequate. Serum iron values of pregnant(96.9ug/dl)and lactating women(93.9ug/dl) were not significantly different from that of the non-pregnant, non-lactating women (97.1ug/dl). There were however, more iron-deficient subjects in the pregnant gorup(17%) and the lactating group(19%) than in the non-pregnant, non-lactating group (8%). A statistically significant positive correlation was shown between the levels of serum folate and iron in lactating women(r=.9694, p<0.05). The results of our study document that folate deficiency is a nutritional problem as prevalent as iron deficiency in Korean women, especially during pregnancy and lactation. For these women a routine folate and iron supplementation might be necessary.

• 대한기계학회논문집B
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• 제22권4호
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• pp.499-509
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• 1998

In the absorption process of water vapor in a liquid film, the composition of the gas phase, in which a non-absorbable gas is combined with the absorbate influences the transport characteristics remarkably. In the present study, the absorption processes of water vapor into aqueous solution of lithium bromide in the presence of non-absorbable gases were investigated analytically. The continuity, momentum, energy and diffusion equations for the solution film and gas phase were formulated in integral forms and solved numerically. It was found that the mass transfer resistance in gas phase increased with the concentration of non-absorbable gas. However the primary resistance to mass transfer was in the liquid phase. As the concentration of non-absorbable gas in the absorbate increased, the liquid-vapor interfacial temperature and concentration of absorbate in solution decreased, which resulted in the reduction of absorption rate. The reduction of mass transfer rate was found to be significant for the addition of a small amount of non-absorbable gas to the pure vapor, especially at the outlet of an absorber where non-absorbable gases accumulated. At higher non-absorbable gas concentration, the decrease of absorption flux was almost linear to the volumetric concentration of non-absorbable gas.

• 한국환경교육학회지:환경교육
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• 제19권2호
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• pp.48-68
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• 2006

This study is designed to develop a certification system for non-formal environmental education educators as part of efforts to nurture non-formal environmental education educators, increase public trust in non-formal environmental education educators and secure structure and sustainability of non-formal environmental education. The job of non-formal environmental education educators-distant from technical expertise functions that are dealt with by existing certification system - belongs to education and service industry, And the certification system I try to develop is different from existing exclusive certification system based on written tests. It is rather an authentication system based on capability development. So its components are somewhat different from those of existing certification system. However, I also tried to ensure that the system should include components which were supposed to be part of basic certification system. The certification system for non-formal environmental education educators in the study is focused on developing a framework for basic certification system. Therefore, I believe that follow up studies may be needed to address execution, i.e., specific evaluation criteria to select organizations in charge of certification system and education course/program respectively, criteria to select instructors who will lead training course/program and decision on whether experiences as eco-guide or nature experience guide should be recognized as experiences for non-formal environmental education educator etc.

• Journal of Periodontal and Implant Science
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• 제27권2호
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• pp.305-315
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• 1997

The purpose of this study was to investigate the effects of smoking on adult periodontitis after non-surgical periodontal therapy. The study population consisted of 40 patients with moderate to advanced periodontitis. Smokers(n=20) were defined as individuals smoking at least twenty cigarettes per day at the time of the initial examination. The non-smoking group(n=20) consisted of individuals who were not smoking at the initial examination. The average age was 42.4 years for the smoking and non-smoking group. Examination regarding plaque index, gingival index, pocket depth and contrast phase microscope were performed. Evaluation were made at the first, the second and the fourth weeks after periodontal non-surgical therapy. The results were as follows: 1. Clinical indices including plaque index, gingival index, and pocket depth were decreased in both smoking and non-smoking group at the first, the second, and the fourth weeks. Especially, clinical indices of non-smokers were more significantly decreased than those of smokers. 2. Non-motile rods were increased and motile rods were reduced at the fourth week. spirochetes were reduced significantly in the non-smoking group at the fourth week. These results suggest that smoking play a minor role in adult periodontitis after non-surgical periodontal therapy.

• Wind and Structures
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• 제31권5호
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• pp.445-457
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• 2020

The buffeting response is a vital consideration for long-span bridges in typhoon-prone areas. In the conventional analysis, the turbulence and structural vibrations are assumed as stationary processes, which are, however, inconsistent with the non-stationary features observed in typhoon winds. This poses a question on how the stationary assumption would affect the evaluation of buffeting responses under non-stationary wind actions in nature. To figure out this problem, this paper presents a comparative study on buffeting responses of a long-span cable-stayed bridge based on stationary and non-stationary perspectives. The stationary and non-stationary buffeting analysis frameworks are firstly reviewed. Then, a modal analysis of the example bridge, Sutong Cable-stayed Bridge (SCB), is conducted, and stationary and non-stationary spectral models are derived based on measured typhoon winds. On this condition, the buffeting responses of SCB are finally analyzed by following stationary and non-stationary approaches. Although the stationary results are almost identical with the non-stationary results in the mean sense, the root-mean-square value of buffeting responses are underestimated by the stationary assumption as the time-varying features existing in the spectra of turbulence are neglected. The analytical results highlights a transition from stationarity to non-stationarity in the buffeting analysis of long-span bridges.

• 한국의류산업학회지
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• 제16권2호
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• pp.319-325
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• 2014

This article describes a method for producing chitosan non-woven fabrics by just hot pressing without the use of a binder. A study has been made of the wet spinning of chitosan fiber. The fibers were rinsed thoroughly in running water and chopped wet into staples of with a length of approximately 5-10 mm. The chopped chitosan staples were dispersed uniformly in water and fabricated using a non-woven making machine. This study examined the formation and the characteristics of chitosan non-woven fabrics manufactured by hot pressing without the use of a binder. The effects of the non-woven fabrication conditions on the thermal, morphological, structural, and physical properties of chitosan non-woven fabric with and without water as a plasticizer were studied. The temperature of the exothermic peak, decomposition of chitosan fibers increased with increasing heating rate. Water in the chitosan fiber effectively plasticized the chitosan fiber. The thermal bonded structure of the wet chitosan fiber with water as a plasticizer was clearly found in many parts of the non-woven fabric at a fabrication temperature of $200^{\circ}C$. The intensity and profile of the (100) plane($2{\theta}=10.2^{\circ}$) and (040) plane($2{\theta}=20.9^{\circ}$) in the chitosan non-woven fabric decreases and became smooth in the non-woven fabric formation by melting.

• 한국정보시스템학회지:정보시스템연구
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• 제27권1호
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• pp.1-20
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• 2018

Purpose The purpose of this study is to identify the determinants of non-use and the dynamic nature of non-use by the qualitative research methodology, grounded theory methodology, as part of identifying the nature of non-use. Design/methodology/approach We applied the grounded theory methodology to a total of 23 college students, including non-users who are not currently using them, users with low intention to use them, and users with high intention to use. We extracted the codes related to the use and proposed the non-use dynamics conversion process based on the coding results. Findings First, the use of information technology can also promote the frequency of use, but can also lead to the use of negative attitudes which would fall in the state of non-use. Second, the user may have both positive and negative attitudes toward the current information technology. Third, if usage is dominated by habits, it is not so easy to change persistent use into an unused state. Fourth, factors that determine the use of specific information technology can be a factor in determining nonuse. This study has contributed to understand the essence of non - use as well as the nature of use, overcoming limitations of quantitative research approach and confirming possibility of grounded theory method in information system research.

• International Journal of Air-Conditioning and Refrigeration
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• 제6권
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• pp.56-66
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• 1998

The absorption process of water vapor in a liquid film is an important process in LiBr-Water absorption system. The composition of the gas phase, in which a non-absorbable gas is combined with the absorbate, influences the transport characteristics. In the present work, the absorption processes of water vapor into aqueous solutions of lithium bromide in the presence of non-absorbable gas are investigated. The continuity, momentum, energy and diffusion equations for the solution film and gas are formulated in integral forms and solved numerically. It is found that the mass transfer resistance in gas phase increases with the concentration of non-absorbable gas. However the primary resistance to mass transfer is in the liquid phase. As the concentration of non-absorbable gas in the absorbate increases, the interfacial temperature and concentration of absorbate in solution decrease, which results in the reduction of absorption rate. The reduction of mass transfer rate is found to be significant for the addition of a small amount of non-absorbable gas to the pure vapor, especially at the outlet of tube where the non-absorbable gas accumulates. At higher non-absorbable gas concentration, the decrease of absorption rate seems to be linear to the concentration of non-absorbable gas.

• Coupled systems mechanics
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• 제6권1호
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• pp.97-111
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• 2017

The present paper reports an analytical study of delamination fracture in the Mixed Mode Flexure (MMF) functionally graded beam with considering the material non-linearity. The mechanical behavior of MMF beam is modeled by using a non-linear stress-strain relation. It is assumed that the material is functionally graded along the beam height. Fracture behavior is analyzed by the J-integral approach. Non-linear analytical solution is derived of the J-integral for a delamination located arbitrary along the beam height. The J-integral solution derived is verified by analyzing the strain energy release rate with considering the non-linear material behavior. The effects of material gradient, crack location along the beam height and material non-linearity on the fracture are evaluated. It is found that the J-integral value decreases with increasing the upper crack arm thickness. Concerning the influence of material gradient on the non-linear fracture, the analysis reveals that the J-integral value decreases with increasing the ratio of modulus of elasticity in the lower and upper edge of the beam. It is found also that non-linear material behavior leads to increase of the J-integral value. The present study contributes for the understanding of fracture in functionally graded beams that exhibit material non-linearity.

• Structural Engineering and Mechanics
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• 제18권2호
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• pp.247-262
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• 2004

In the earlier application of the spline finite strip method(FSM), the uniform B3-spline functions were used in the longitudinal direction while the conventional interpolation functions were used in the transverse direction to construct the displacement filed in a strip. To overcome the shortcoming of the uniform B3-spline, non-periodic B-spline was developed as the displacement function. The use of non-periodic B3-spline function requires no tangential vectors at both ends to interpolate the geometry of shell and the Kronecker delta property is also satisfied at the end boundaries. Recently, non-periodic spline FSM which was modified to have a multiple knots at the boundary was developed for the shell analysis and applied to the analysis of bridges. In the formulation of a non-symmetric spline finite strip method, the concepts of non-periodic B3-spline and a stress-resultant finite strip with drilling degrees of freedom for a shell are used. The introduction of non-symmetrically spaced knots in the longitudinal direction allows the selective local refinement to improve the accuracy of solution at the connections or at the location of concentrated load. A number of numerical tests were performed to prove the accuracy and efficiency of the present study.