• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.8
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• pp.711-719
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• 2017

Bladeless fan is becoming increasingly popular owing to its advantages, such as improved safety, easy to clean, and attractive shape. However, many people are reluctant to purchase it because of several disadvantages, such as noise and moderate wind; therefore, research on how improve wind generation without increasing the motor speed is required. This study investigates the optimization of the shape of the nozzle and nearby surface using CFD (Computational Fluid Dynamics) simulation, ANSYS fluent. The results are analyzed by ANOM (analysis of mean) and interaction analysis; therefore this study suggests the variables of affecting Coanda effect and satisfy the govern equation, the conservation of momentum. The optimal combination was found through a predictive equation. In this study, factors and levels that affect the mass flow rate were selected and experimental points were arranged using the orthogonal array table. The value of the mass flow rate was confirmed by ANSYS fluent, which is a CFD program. Through the ANOM, it was confirmed that the nozzle distance is the most influential parameter affecting the mass flow rate. Furthermore, the mass flow rate obtained from the predictive equation and the mass flow rate from the CFD correspond to the largest values. Results from this study confirmed that the mass flow rate is increased by a change in the shape, even if the motor speed did not increase.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.1-13
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• 2014

Lithium ion batteries (LIBs) are the state-of-the-art technology among electrochemical energy storage and conversion cells, and are still considered the most attractive class of battery in the future due to their high specific energy density, high efficiency, and long cycle life. Rapid development of power-hungry commercial electronics and large-scale energy storage applications (e.g. off-peak electrical energy storage), however, requires novel anode materials that have higher energy densities to replace conventional graphite electrodes. Germanium (Ge) and silicon (Si) are thought to be ideal prospect candidates for next generation LIB anodes due to their extremely high theoretical energy capacities. For instance, Ge offers relatively lower volume change during cycling, better Li insertion/extraction kinetics, and higher electronic conductivity than Si. In this focused review, we briefly describe the basic concepts of LIBs and then look at the characteristics of ideal anode materials that can provide greatly improved electrochemical performance, including high capacity, better cycling behavior, and rate capability. We then discuss how, in the future, Ge anode materials (Ge and Ge oxides, Ge-carbon composites, and other Ge-based composites) could increase the capacity of today's Li batteries. In recent years, considerable efforts have been made to fulfill the requirements of excellent anode materials, especially using these materials at the nanoscale. This article shall serve as a handy reference, as well as starting point, for future research related to high capacity LIB anodes, especially based on semiconductor Ge and Si.

• Applied Chemistry for Engineering
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• v.23 no.2
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• pp.176-182
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• 2012

The methane dry reforming has received the considerable attention in recent years, mainly as an attractive route to produce synthesis gas (CO, $H_2$) from green-house gases ($CH_4$, $CO_2$) for resources. However, this process has not been commercialized due to the high temperature and catalyst deactivation. In this study, Co-Ru-Zr catalysts supported on $SiO_2$ were studied for the characterization of methane dry reforming reaction and the preliminary data for process development were achieved. The crystal structure of catalysts was measured by XRD, the surface area and pore size were analyzed by BET, and the element composition of catalyst were analyzed by EDS. Conversions of methane and carbon dioxide were analyzed by GC. In addition, reaction rate constants were obtained from the reaction kinetic study and the optimum catalyst size that does not affect mass transfer from reactants was also determined. The selected pellet-type catalyst maintained activation for 720 h at $850^{\circ}C$.

• Korean journal of food and cookery science
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• v.21 no.6 s.90
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• pp.769-775
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• 2005

In this study we isolate substances to serve as dietary resources in order to replace the female hormone. Silkworm (Bombyx mori) is one of the most attractive hosts for large-scale production of eukaryotic proteins which have been proven safe as a dietary resource. We report on the estrogenicity of a mixture of silkworm pupa and herbs (Ginseng,Ulkeum, and Hasuo) using the immature rat uterotrophic assay in vivo. Silkworm pupa aqueousextract (KW) and silkworm oil extract (KO) induced effects on the immature rat uterotrophic assay. KO showed neither positive uterotrophic response nor inhibition on E2 induced effect, while KW and MK (mixture of KW and herbs) showed both of the effects. It is concluded that ethanol extracts from silkworm might be a good, therapeutic, natural product for hormone-deficient diseases.

• The Korean Journal of Food And Nutrition
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• v.30 no.5
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• pp.1025-1034
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• 2017

As the consumption of wheat has increased recently, the number of people who have digestive problems resulting from gluten in wheat has also increased. Teff has an attractive nutritional profile, as it not only gluten-free but also high in dietary fiber, protein, iron, and calcium. Seven samples were prepared for this study. The quality characteristics of gluten-free noodles were evaluated based on pH, salinity, water absorption, turbidity, color, texture properties, tensile strength, and SEM. The pH value was the highest in TF100 with a pH of 6.66 and the lowest in the control with a pH of 6.42. Salinity showed no significant difference among all samples, and it ranged from 0.02~0.04% (p<0.05). Water absorption was the highest in TFX with a value of 66.11%, and the lowest in the control with a value of 44.81%. Turbidity showed no significant difference among all samples, and it ranged from 0.14~0.21 O.D. (p<0.05). While the lightness and yellowness values decreased with an increase in teff flour content, the redness value tended to decrease. The color difference value was the highest in the sample group without gluten. Based on the texture profile analysis, the hardness was highest in the control with a value of 46.74 N and lowest in TF100 with a value of 18.34 N. The springiness showed no significant difference among all samples. The cohesiveness was highest in the control with a value of 0.92 N. The chewiness decreased with an increase in teff flour content. Although the control with gluten had the highest tensile strength at $3.42kg/cm^2$, TFX had considerable tensile strength at $2.30kg/cm^2$. This study demonstrated the processability of gluten-free noodles using teff flour.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.9
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• pp.543-551
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• 2016

Recently, the cultural industry has become an attractive industry which is having a dramatic effect with the rise of Hallyu offering many possibilities for development. Specially, the marketing techniques employed by the performing arts industry started to change to respond to consumer tastes and demands like other commodity markets, as the popular performing arts industry began to receive attention as a promising industry. It is important to identify the behavior of consumers in order to actively deal with the demands and tastes of consumers that are becoming increasingly diverse and individualized. The performing arts market needs to recognize the importance of its audience and to apply appropriate marketing techniques. This study attempted to empirically identify the value of performing arts perceived by the audience and to investigate the influence of the relationship between the perceived value, attitude formation and satisfaction with performing arts. In order to examine the influence of the value of performing arts on attitude and customer satisfaction, a reliability analysis and factor analysis were conducted to investigate the dependability and validity of the measured variables. In order to achieve the study's intended purpose, the structural equation model (SEM) was utilized as the core analysis method. As a result, it was found that the perceived value and attitude towards performing arts have a positive effect on customer satisfaction. The results of this study are expected to be used as the basic data for organizations that plan performances to improve their marketing and promotion around the audience and for more specific and detailed research in the future.

• Journal of Korean Neurosurgical Society
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• v.61 no.6
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• pp.716-722
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• 2018

Objective : Lateral interbody fusion (LIF) is attractive as a less invasive technique to address anterior spinal pathology in the treatment of adult spinal deformity. Its own uses and benefits in treatment of adult degenerative scoliosis are undefined. To investigate the radiographic and clinical outcomes of LIF, and staged LIF and posterior spinal fusion (PSF) for the treatment of adult degenerative scoliosis patients, we analyzed radiographic and clinical outcomes of adult degenerative scoliosis patients who underwent LIF and posterior spinal fusion. Methods : Forty consecutive adult degenerative scoliosis patients who underwent LIF followed by staged PSF at a single institution were retrospectively reviewed. Long-standing 36" anterior-posterior and lateral radiographs were taken preoperatively, at inter-stage, 3 months, 1 year, and 2 years after surgery were reviewed. Outcomes were assessed through the visual analogue scale (VAS), 36-Item Short Form Health Survey (SF-36), and Oswestry Disability Index (ODI). Results : Forty patients with a mean age of 66.3 (range, 49-79) met inclusion criteria. A mean of 3.8 levels (range, 2-5) were fused using LIF, while a mean of 9.0 levels (range, 3-16) were fused during the posterior approach. The mean time between stages was 1.4 days (range, 1-6). The mean follow-up was 19.6 months. Lumbar lordosis was significantly restored from $36.4^{\circ}$ preoperatively up to $48.9^{\circ}$ (71.4% of total correction) after LIF and $53.9^{\circ}$ after PSF. Lumbar coronal Cobb was prominently improved from $38.6^{\circ}$ preoperatively to $24.1^{\circ}$ (55.8% of total correction) after LIF, $12.6^{\circ}$ after PSF respectively. The mean pelvic incidence-lumbar lordosis mismatch was markedly improved from $22.2^{\circ}$ preoperatively to $8.1^{\circ}$ (86.5% of total correction) after LIF, $5.9^{\circ}$ after PSF. Correction of coronal imbalance and sagittal vertebral axis did not reach significance. The rate of perioperative complication was 37.5%. Five patients underwent revision surgery due to wound infection. No major perioperative medical complications occurred. At last follow-up, there were significant improvements in VAS, SF-36 Physical Component Summary and ODI scores. Conclusion : LIF provides significant corrections in the coronal and sagittal plane in the patients with adult degenerative scoliosis. However, LIF combined with staged PSF provides more excellent radiographic and clinical outcomes, with reduced perioperative risk in the treatment of adult degenerative scoliosis.

• Food Science and Industry
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• v.45 no.2
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• pp.10-18
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• 2012

Maesil began to grow in Gwangyang after the old Mr. Yulsan Kim Oh-cheon brought 5,000 trees of maesil(Prunes mume) from Japan in 1931. Today, Gwangyang maesil comprises approximately 25% of total national output. Gwangyang produces a variety of foods, manufactured foods and beverages using maesil. Besides, numerous tourists came to the 15th Gwangyang International Ume Flower Culture Festival to enjoy the festival and appreciate blossoming ume flowers. More than 1.9 million people visited Blue Ume Flower Farm in Gwangyang in the year of 2010. As many visitors came to the city simultaneously, however, there occurred confusion. So, it is thought that the following measures are necessary to enhance the tourism value of Gwangyang maesil. First, a symbolic story for Gwangyang maesil or maehwa(ume flower) needs to be created. Second, snack foods for sightseers need to be developed. Third, diverse attractive elements to prolong tourists' stays are worth developing. Fourth, it is necessary for Gwangyang to hold competitions for ideas to activate tourism through maesil. Fifth, Gwangyang needs to promote collaborative development of tourist items and collaborative tourism marketing in close cooperation with neighboring cities and counties. Finally, it is worthwhile for Gwangyang to host an international fruits and seeds exposition or exhibition and it needs to strengthen active promotion and marketing suitable for the Smart Age.

• Development and Reproduction
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• v.23 no.3
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• pp.223-229
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• 2019

Type 2 diabetes mellitus (T2DM) is characterized by insulin resistance (IR). T2DM is correlated with obesity and most T2DM medications have been developed for enhancing insulin sensitivity. Silk protein fibroin (SPF) from spiders has been suggested as an attractive biomaterial for medical purposes. We generated transgenic rice (TR) expressing SPF and fed it to diabetic $BKS.Cg-m+/+Lepr^{db}$ mice to monitor the changes in blood glucose levels and adipose tissue proteins associated with energy metabolism and insulin signaling. In the present study, the adipocyte size in abdominal fat in TR-SPF-fed mice was remarkably smaller than that of the control. Whereas the adenosine monophosphate-activated protein kinase (AMPK)-activated protein kinase and insulin receptor substrate 1 (IRS1) protein levels were increased in abdominal adipose tissues after TR-SPF feeding, levels of six-transmembrane protein of prostate 2 (STAMP2) proteins decreased. Phosphorylation of AMPK at threonine 172 and IRS1 at serine 307 and tyrosine 632 were both increased in adipose tissues from TR-SPF-fed mice. Increased expression and phosphorylation of IRS1 at both serine 307 and tyrosine 632 in adipose tissues indicated that adipocytes obtained from abdominal fat in TR-SPF-fed mice were more susceptible to insulin signaling than that of the control. STAMP2 protein levels decreased in adipose tissues from TR-SPF-fed mice, indicating that STAMP2 proteins were reducing adipocytes that were undergoing lipolysis. Taken together, this study showed that TR-SPF was effective in reducing blood glucose levels in diabetic mice and that concurrent lipolysis in abdominal adipocytes was associated with alterations of AMPK, IRS1, and STAMP2. Increased IRS1 expression and its phosphorylation by TR-SFP were considered to be particularly important in the induction of lipolysis in adipocytes, as well as in reducing blood glucose levels in this animal model.

• Bulletin of the Society of Naval Architects of Korea
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• v.6 no.1
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• pp.25-34
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• 1969

From viewpoints of over-all ship economy the straight framed V-bottom hull forms with chines are considered to be attractive even for usual commercial vessels, because increments of resistance over that of round hull forms, if any, can be well compensated with reduction in construction cost.[1] To investigate the influences of both prismatic coefficient and chine elevation on resistance performance, three models of straight-framed V-bottom hull forms which are similar to Prof. C. Ridgely-Nevitt's W-18, W-8, and W-20[2],[3] in size and hull form coefficients were tested at the SNU Ship Model Towing Tank for resistance measurements. They are of Cp=0.60, 0.65 and 0.70 and of ${\Delta}/(0.01L)^3=300$. Influence of variation of chine elevation on resistance performance were observed with the test results obtained at normal condition, and at the trimed by the stern by 2% and 4% of $L_{bp}$ at normal condition under same displacement. The hull form characteristics are shown in Table 1, and in Fig. 1, 2, 3, 4 and 5. The test results are shown in Fig 8, 9 and 10 in the form of Cr vs. $V/\sqrt{L}$ curves taking Cp as a parameter for normal condition, trim by the stern in 2% and 4% $L_{bp}$ at normal condition , respectively. Cr vs. $V/\sqrt{L}$ curves taking trim condition as a parameter are also shown in Fig 11, 12 and 13 for Cp=0.60 and 0.70, respectively. The best and the worst trim condition at given $V/\sqrt{L}$ in viewpoint of Cr are plotted for each Cp-value as shown in Fig 14, 15 and 16. From the above results the following conclusions are derived: (1) In general, the resistance performance of the straight-framed V-bottom hull forms are not inferior to those of round hull forms. At a certain range of $V/\sqrt{L}$ the former gives less resistance than the latter. (2) Regarding influences of Cp on Cr, it is observed that, at $V/\sqrt{L}$ less than about 0.925, the greater Cp-value gives the more increment of Cr, and that, at $V/\sqrt{L}$ greater than about 0.925 the smaller Cp-value gives the more increment of Cr. It is also noteworthy that the model of Cp=0.70 has remarkable hump on Cr vs. $V/\sqrt{L}$ curve between $V/\sqrt{L}=0.80$ and 0.90. (3) For higher speed within the test range, the chine elevation having the steeper slope around bow and the easier slope around amidship and stern, refered to watering, give the better results in resistance performance. (4) Assuming the chine elevations adopted for the tested models were not of the best, we would expect further improvement of resistance performance for such form. Hence, a systematic study on chine elevation is very disirable to prepare design data of general purpose for the such hull forms.