• The KSFM Journal of Fluid Machinery
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• v.13 no.3
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• pp.37-42
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• 2010

This study investigated on details of flow characteristics of a multi-blade fan for domestic ventilation. Experiments and analysis were carried out to describe on flow pattern with variations of cut-off angle near the scroll housing throat, which were performed by PIV measurement for the flow field and by total pressure probes. The stagnation point at cut-off region of the fan moves to the exit of the scroll housing as the cut-off angle increases. The movement of stagnation point and the variation of throat area of the scroll housing influence to the distribution of velocity magnitude at the exit of the fan. Furthermore, a large distortion of the velocity distribution at the scroll exit causes to increase mixing loss along the flow path.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.25 no.3
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• pp.399-407
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• 2001

The Surface, generated by end milling operation, is deteriorated by tool runout, vibration, friction, tool deflection, etc. Especially in cornering cut, surface accuracy is usually determined by varying cutting forces, which causes tool deflections. Cutting conditions like feed rate is usually kept constant during machining a part, which causes dimensional error in severe cutting. Cornering cut is a typical example of deterioration of surface accuracy when constant feed rate is applied. Therefore it becomes important to develop NC post processor module to determine optimal cutting conditions in various cutting situations. In this paper, cutting force is predicted in cornering cut with flat end mill and feed rate is determined by constraining constantly resultant force. Also some control characteristics of CNC machining center are evaluated.

• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.269-273
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• 1990

The proton conserving effect of diffusion with self-aligned SiO2-cladding is investigated by infrared transmission spectra. Based on the proton conserving effect, proton-diffused channel waveguides with self-aligned SiO2-cladding substrates. And an electro-optic cutoff modulator with self aligned electrode that utilizes a single-mode proton-diffused channel waveguide in a Y-cut XX-propagating LiNbO3 substrate is fabricated. Over 20 dB extinction has been achieved with applied voltage of 15V.

• Proceedings of the Optical Society of Korea Conference
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• 1991.06a
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• pp.110-114
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• 1991

A guided-wave electrooptic Mach-Zehnder interferometric modulator was fabricated on Y-cut acoustic grade LiNbO3 process. In order to reduce the electrode capacitance, serial capacitance electrode(SCE) structure was adopted. Extinction ratio more than 30dB was obtained with V$\pi$ of 4.69 volt at λ= 0.6328${\mu}{\textrm}{m}$. Frequency response was measured by using the swept frequency technique, and the bandwidth of the modulator was about 1GHz.

• ETRI Journal
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• v.36 no.4
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• pp.635-642
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• 2014

Three-dimensional integrated circuits (3D ICs) implement heterogeneous systems in the same platform by stacking several planar chips vertically with through-silicon via (TSV) technology. 3D ICs have some advantages, including shorter interconnect lengths, higher integration density, and improved performance. Thermal-aware design would enhance the reliability and performance of the interconnects and devices. In this paper, we propose thermal-aware floorplanning with min-cut die partitioning for 3D ICs. The proposed min-cut die partition methodology minimizes the number of connections between partitions based on the min-cut theorem and minimizes the number of TSVs by considering a complementary set from the set of connections between two partitions when assigning the partitions to dies. Also, thermal-aware floorplanning methodology ensures a more even power distribution in the dies and reduces the peak temperature of the chip. The simulation results show that the proposed methodologies reduced the number of TSVs and the peak temperature effectively while also reducing the run-time.

• Journal of Sericultural and Entomological Science
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• v.13 no.1
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• pp.13-16
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• 1971

In order to clarify the effect of the time and height of cut in autumn on the occurrence of mulberry magare blight disease, mulberry fold experiment had been tarried out between the autumn 1970 and the spring 1971. The results obtained summarrized as follows. 1) In case of intermediate cutting, the occurrence of the mulberry magare blight disease and its damage showed great difference among the times to cut the tree. That is the intermediate cutting between the 9th and the 21st of September was attacked by the disease and to cut before the 3rd of September and after tile 3rd of October was not attacked by the disease. In the damage by the cut shoot time, intermediate cutting between the 15th and the 18th of September was most seriously having heavy damage and to cut before the 12th and of the 21st of September was Bight damage. 2) Heavier damage was observed in the plot cut above 30cm from the ground compared with the plot cut middle of the branches of the tree.

• Journal of Korean Tunnelling and Underground Space Association
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• v.11 no.4
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• pp.419-425
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• 2009

Recently, the number of shallow tunnel construction increases to improve the structural safety and environment-friendliness. In Semi-Cut and Cover Method, ground is excavated to the crown arch level and braced rib arch is set to backfill before the excavation of lower face. Semi-Cut and Cover Method is proposed to solve the problems occurred by the conventional Cut and Cover Method, such as unstability, high-cost and the large cutting slope to be reinforced. In this paper, the behaviors of Braced Rib Arch in shallow tunnel excavated by semi-cut and cover method was studied. Model tests in 1:10 Scale were performed in real construction sequences. The distance between supports of rib arch was 1.8 m and the length of spacer was 1.0 m. the size of test pit was 4.0 m (width)$\times$3.3 m (length) 4.0 m (height) in dimension. Tests results show that backfill load acting on arch was smaller than that in the conventional Open-Cut Method.

• Journal of the Korean Society of Clothing and Textiles
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• v.32 no.2
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• pp.271-283
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• 2008

The purpose of this study is to provide information on how to improving wearing sensation and fit of boots-cut jean through analysis of the actual wearing conditions and dissatisfaction. In order to compile the information about dissatisfaction with the appropriateness of the fit of boots-cut jean, a questionnaire was administered to 150 females(between the ages of 20 and 39) living in Gwang-ju, analyzed using the SPSS WIN 12.0 program. Also, 6 blue jean manufactures were investigated, the study method was a interview about company present status, sizing system and pattern of boots-cut jean. The result of this study were as follow: 1. In wearing conditions, the 20's(51.6%) to 30's(69.1%) is found the best preferred jean is boots-cut style. The reason why consumers prefer boots-cut jeans with wearing fit does to seem charming bodyline of the adult female. 2. Body type groups by drop was classified with the usual waist, the thick waist, the thin waist. The differences among age groups, body type and so on were compared using the chi-square test. Dissatisfaction of the fit of the thick waist and the thin waist was higher than the usual waist. 3. Research on the production sizing system of 6 blue jean brands showed the total sizing system of each manufacture were $3{\sim}9$, they were reflected the sizing system of the korean Industrial Standards(KS K 0051). Therefore, it is considered necessary for boots-cut jeans pattern and sizing system for Korean consumer's body shape.

• The Journal of Korean Medicine
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• v.39 no.4
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• pp.51-61
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• 2018

Introduction: This study evaluated whether body mass index (BMI) and waist circumference (WC) cut-offs for predicting metabolic syndrome (MetS) were different according to Sasang constitutional type. Methods: Data were obtained from 3,117 South Koreans (20-90 years old), and MetS was defined according to the revised NCEP-ATPIII criteria. Age-adjusted BMI and WC cut-offs were calculated according to Sasang constitutional type (Soyangin [SY], Taeeumin [TE], and Soeumin [SE]), sex, and age (men: ${\geq}40$ vs. <40 years, women: ${\geq}50$ vs. <50 years). Results: The prevalences of MetS were 29.9% (<40-year-old men), 35.1% (${\geq}40$-year-old men), 14.8% (<50-year-old women), and 47.7% (${\geq}50$-year-old women). The BMI ($kg/m^2$) and WC (cm) cut-offs for <40-year-old men were 25.9 and 89.9 (SY), 25.5 and 90.5 (TE), and 21.8 and 86.2 (SE). The cut-offs for ${\geq}40$-year-old men were 23.1 and 88.9 (SY), 25.0 and 89.9 (TE), and 22.2 and 87.5 (SE). The BMI and WC cut-offs for <50-year-old women were 22.5 and 81.2 (SY), 25.1 and 83.0 (TE), and 21.5 and 79.8 (SE). The cut-offs for ${\geq}50$-year-old women were 22.2 and 80.5 (SY), and 25.2 and 89.1 (TE), and 21.9 and 80.3 (SE). Conclusions: The BMI and WC cut-offs for identifying MetS varied according to Sasang constitution type.

• The Korean Journal of Food And Nutrition
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• v.35 no.2
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• pp.150-158
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• 2022

The purpose of this study was to assess consumption and satisfaction with fresh-cut produce in Korean adults. In this study, an online survey November 9~13, 2020 was conducted with 982 Korean adults age 19~64 (490 males and 492 females) with experience in purchasing fresh-cut produce in the past year. Among all respondents, the percentage with experience in buying 'washed or peeled vegetables' was the highest (71.18%), followed by those in buying 'packaged salads/sprouts/ssam vegetables' (64.15%), 'pre-cut fruits/fruit cups' (59.98%), 'pre-cut or minced vegetables' (56.01%), and 'washed or peeled fruits' (53.67%), respectively. Among the types of fresh-cut produce, 'packaged salads/sprouts/ssam vegetables' showed the highest satisfaction score at 3.73 pts, and the overall satisfaction score of fresh-cut produce consumption was also 3.73 pts. Compared to male respondents, female respondents showed a significantly higher percentage of respondents that purchased 'packaged salads/sprouts/ssam vegetables' (p=0.0409), significantly higher satisfaction scores (p=0.0124), and a higher percentage of respondents considering 'freshness' important when purchasing (p<0.0001). Additionally, the group with high household income comprised a significantly higher ratio of respondents considering 'eco-friendly or organic status' important. The study results may facilitate identify areas for improvement of fresh-cut produce in the future.