• Magazine of the Korea Concrete Institute
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• v.2 no.3
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• pp.65-72
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• 1990

Theoretical expressions were dcrived for the numher of fibers per unit cross-sectional area in fiber reinforced concrete, with due consideration given to the effects of the surrounding boundaries. The number of fibers per unit cross-sectional area in steel fiber reinforced concrete was also measured experimentally for the specimens incorporating various volume fractions of fibers of different types. Statistical evaluation of the measured value was then performed in order to assess the differences in fiber concentration at different location on tbe cross section. Degree of reorientation of steel fibers in concrete occuring during vibration was examined by com¬paring the differences in the computed and measur'ed values of the number of fibers per unit cross-sectional area.

• Journal of the Korean Society of Physical Medicine
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• v.6 no.4
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• pp.407-414
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• 2011

Purpose : The aim of this study was to clarify the lung capacity, maximal insufflation capacity, and peak cough flow when a mechanical insufflation-exsufflation(MIE) method was used to increase Duchenne muscular dystrophy patients' lung function. Methods : The subjects of the study were 21 patients with Duchenne muscular dystrophy. They were randomly selected from patients within the boundaries of the selection criteria, and divided into two groups; The subject group(n=11) used the mechanical insufflation-exsufflation method with traditional therapeutic exercise. The control group(n=10) used only traditional therapeutic exercise. Results :The results indicated that maximal insufflation capacity, unassisted peak cough flow and assisted peak cough flow significantly increased in the subject group(p<.05). By contrast, in the control group, the results didn't indicate the significant differences from the variable. There were significant differences in maximal insufflation capacity and assisted peak cough flow between the subject group and the control group before and after the application of the mechanical insufflation-exsufflation method. Conclusion : A mechanical insufflation-exsufflation method has positive effects on the improvements of cough functions and that of pulmonary functions such as lung volume, lung elasticity in patients with Duchenne muscular dystrophy.

• Transactions of the Korean Society of Mechanical Engineers
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• v.9 no.6
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• pp.750-756
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• 1985

Experimental investigation was carried out to study the natural convection of water and silicon oil due to end temperature differences in a horizontally insulated rectangular enclosure of aspect ratio 0.1 with a special attention on the core configuration in the laminar boundary-layer flow regime. Rayleigh number ranges covered herein are Ra=4.40 * 10$^{6}$ -9.64 * 10$^{7}$ for water and Ra=1.69*10$^{5}$ -3.80*10$^{6}$ for silicon oil, respectively. In the case of water, for Ra.geq.2.21 * 10$^{7}$ there appeared distinct horizontal thermal layers adjacent to the horizontal boundaries in the core and the temperature distribution outside the horizontal thermal layers, i.e., in the mid-core region, is vertically stratified. The core flow pattern was shown to be nonparallel with a weak back flow in the mid-core for Ra.geq.3.63 *10$^{7}$ . In the case of silicon oil, distinct horizontal thermal layers appeared along the core horizontal boundaries for Ra.geq.1.27 * 10$^{6}$ with a stratified temperature distribution in the mid-core, but the core flow pattern in this case was shown to be parallel. In addition, secondary flow appeared near the hot wall for Ra.geq.3.80 * 10$^{6}$ . Nusselt number, Nu, was found to be proportional to R $a^{0.3}$ for water and R $a^{0.28}$ for silicon oil in the boundary-layer flow regime. There also in an indication from the comparison with other results that Nu is independent of aspect ratio for water in the boundary-layer flow regime in low aspect ratio enclosures.res.

• The Research Journal of the Costume Culture
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• v.21 no.6
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• pp.961-966
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• 2013

Being one of the most important textile and apparel producers for years, Turkey began to become active in terms of retailing. Although retailing industry is in its growing phase, the social and economic influences caused the customers' tastes and demands to be more distinctive and segmented in parallel with the advancement of the retail industry. Therefore, the retail industry began to develop in more fragmented way where clear boundaries between different types of retailers were established. In this study, the apparel retail market is overviewed and analyzed within the context for determination of the current situation and future prospective. To this aim, the textile and apparel companies that are active in Turkey were classified into groups based on the type of distribution channels they used. Then, the performances of the groups were established using the secondary type of resources. Finally, the findings were summarized, by showing the similarities and differences between different channels.

• Korean Journal of Metals and Materials
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• v.47 no.6
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• pp.356-362
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• 2009

In order to vary the primary recrystallization textures, AA 1050 sheets were cold rolled in two different manners. Differences in cold rolling schedule gave rise to the formation of different cold rolling textures also leading to the formation of different primary recrystallization textures. Upon annealing for grain growth, changes in microstructure and texture hardly occurred in the sample depicting Cube recrystallization texture, while grain growth was accompanied with the development {001}<100> Cube texture in the sample displaying a recrystallization texture comprising of weak rolling texture components. The selective growth of Cube oriented grains is attributed to the high mobility of their grain boundaries.

• Journal of the Korean Institute of Telematics and Electronics B
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• v.32B no.8
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• pp.1091-1098
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• 1995

This paper proposes an efficient noiseless encoding method of vector quantization(VQ) index using a dynamic index mapping. Using high interblock correlation, the proposed index mapper transforms an index into a new one with lower entropy. In order to achieve good performance with low computational complexity, we adopt 'the sum of differences in pixel values on the block boundaries' as the cost function for index mapping. Simulation results show that the proposed scheme reduces the average bitrate by 40 - 50 % in ordinary VQ system for image compression. In addition, it is shown that the proposed index mapping method can be also applied to mean-residual VQ system, which allows the reduction of bitrate for VQ index by 20 - 30 %(10 - 20 % reduction in total bitrate). Since the proposed scheme is one for noiseless encoding of VQ index, it provides the same quality of the reconstructed image as the conventional VQ system.

• Advances in materials Research
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• v.13 no.2
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• pp.141-151
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• 2024

The aim of this work was to determine the behavior of alloy elements and compounds formed during solidification in the manufacturing process of the CuAgZrCr alloy under an oxidizing environment. Bulk and surface analysis techniques, such as Scanning Electron Microscopy (SEM), X-ray Photoelectron Spectroscopy (XPS), Raman and X-ray diffraction (XRD) were used to characterize the phases obtained in the solidification process. In order to focus the analysis on the on grain boundary interface, partial removal of the matrix phase by acid attack was performed. The compositional differences obtained by SEM-EDX, Raman and XPS on post-manufacturing materials allowed us to conclude that the composition of grain boundaries of the alloy is directly influenced by the oxidizing environment of alloy manufacturing.

• Journal of Families and Better Life
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• v.30 no.6
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• pp.103-114
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• 2012

This paper aims to investigate changes in Korean family structures by reflecting on the perception of traditional family rites and family systems. In-depth interviews were conducted with 17 married middle-aged men (9) and women (8) who had at least one child. Findings were as follows: First, both married middle aged men and women internalized Confucianism. They thought that the head of household, who was male as far as possible, was needed for the formation of a normal family. In addition, both of married middle-aged men and women recognized married women as outsiders based on Chul-ga-we-in-sa-sang. And they put parents-children relationships ahead of couple relationships and supported Jang-ja-woo-dae-sang-sok (privileging the eldest son over the other children in terms of the distribution of family resources and inheritance based on Confucianism). However, there were some differences to support the use of Hang-ryul-ja, which is based on expressing the character of generation by sharing the first name, and the importance of Jok-bo. which is based on traditional family genealogical records. Second, even though women internalized Confucianism, they did not attach traditional meanings to memorial services for ancestors to the extent that men did and defined family members as a procreation family boundaries unlike men, who defined family boundary as original family members and procreation family members. In conclusion, even though family laws and culture have evolved from the patrilineal family system to one which promotes gender equality, married men and women internalize Confucianism. Instead, some transformations are evident from the perspective of females in terms of memorial services for ancestors and family boundaries.

• Journal of the Korean Wood Science and Technology
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• v.21 no.2
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• pp.73-80
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• 1993

Pinus koraiensis is one of the most important reforestation species which had widely been planted around the country. Therefore, there are great research needs on the fundamental properties of wood to extend the frequency of uses and adequate availabilities. Research results on the characteristics of anatomical wood properties and changes are summarized as follows: 1. At a horizontal direction of tree trunk, the tracheid length at outer wood gradually becomes shorter as it reaches to pith. The tracheid length having between 32 and 42 annual rings showed over 2.5 times longer than that of pith, and also its length increases from the bottom to the top of the stem. 2. The tracheid diameters in latewood showed a little fluctuations, and the shortest near to the pith in earlywood. The tracheid diameters in earlywood are more than 2 times those of latewood, and the differences between the mature and juvenile wood in earlywood are less than 10${\mu}m$. 3. The tracheid wall thickness in early wood showed a little fluctuations. On the contrary, tracheid wall thickness in latewood rapidly increases from the pith to the bark. The tracheid wall of mature wood showed 10 to 20% thicker than that of juvenile wood. 4. The fibril angle at the secondary walls of tracheid within an annual ring showed higher degree in earlywood than that of latewood. The highest tracheid fibril angle was observed at around the pith of both earlywood and latewood. Then, fibril angle slowly decreased toward outer wood, and was stabilized after 15 years. 5. Structural boundaries between mature and juvenile wood from Pinus koraiensis are divided by 13 to 19 annual ring and distance of 5 to 8cm from the pith.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2002.10a
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• pp.361-364
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• 2002

The WASP model was applied to Bokha stream with 8.4km of its main stem located in Ichon-gun, Kyonggi province in Korea. The stream was divided into 26 segments with each of 400m length, and 5 segments were embraced boundaries of its tributaries. The parameters of the model were calibrated by the trial and error method to minimize differences between observed and simulated concentration of water quality constituents. The correlation coefficients for DO, $NO_3-N,\;PO_4-P$ and organic P showed high values providing the ability of simulation. The correlation coefficients for BOD and $NH_3-N$ showed low values in both calibration and verification test.