• Food Science and Preservation
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• v.16 no.4
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• pp.472-481
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• 2009

Response surface methodology (RSM) is frequently used for optimization studies. In the present work, RSM was used to determine the antimicrobial activitiesof grapefruit seed extract (GFSE) and a lactic acid mixture (LA) against Staphylococcus aureus, Bacillus cereus, Escherichia coli, Salmonella typhimurium, Pseudomonas fluorescens, and Vibrio parahaemolyticus. A central composite design was used to investigate the effects of independent variables on dependent parameters. One set of antimicrobial preparations included mixtures of 1% (w/w) GFSE and 10% (w/w) LA, in which the relative proportions of component antimicrobials varied between 0 and 100%. In further experiments, the relative proportions were between 20% and 100%. Antimicrobial effects against various microorganisms were mathematically encoded for analysis. The codes are given in parentheses after the bacterial names, and were S. aureus ($Y_1$), B. cereus ($Y_2$), E. coli ($Y_3$), S. typhimurium ($Y_4$), P. fluorescens ($Y_5$), and V. parahaemolyticus ($Y_6$). The optimum antimicrobial activity of the 1% (w/w) GFSE:10% (w/w) LA mixture against each microorganism was obtained by superimposing contour plots ofantimicrobial activities on measures of response obtained under various conditions. The optimum rangesfor maximum antimicrobial activity of a mixture with a ratio of 1:10 (by weight) GFSE and LA were 35.73:64.27 and 56.58:43.42 (v/v), and the optimum mixture ratio was 51.70-100%. Under the tested conditions (a ratio of 1% [w/w] GFSE to 10% [w/w] LA of 40:60, and a concentration of 1% [w/w] GFSE and 10% [w/w] LA, 70% of the highest value tested), and within optimum antimicrobial activity ranges, the antimicrobial activities of the 1% (w/w) GFSE:10% (w/w) LA mixture against S. aureus ($Y_1$), B. cereus ($Y_2$), E. coli ($Y_3$), S. typhimurium ($Y_4$), P. fluorescens ($Y_5$), and V. parahaemolyticus ($Y_6$) were 24.55, 25.22, 20.20, 22.49, 23.89, and 28.04 mm, respectively. The predicted values at optimum conditions were similar to experimental values.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.14 no.1
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• pp.187-198
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• 2019

The purpose of this study is to seek ways of utilizing TLBMC by understanding business model of social ventures that are accompanied by social and environmental as well as economic missions. In order to achieve this, business models from economic, environmental and social perspectives will be analyzed, and we seek to enhance sustainability of social venture entrepreneurs. As the analysis tool, TLBMC(Triple Layered Business Model Canvas) expands upon the business model canvas that is widely utilized and recognizes economical terms. The TLBMC is proposed by Joyce, A., & Paquin, R. L.(2016) to help achieve a holistic view with horizontal and vertical associations. The study tries to overcome limitations of previous studies and observe a variety of economic, environmental, and social perspectives that social ventures should have with the TLBMC. As a result, it has the following implications; Firstly, creating separate social, environmental and economic business model canvas helps a business to have a holistic approach. Secondly, it was found that social venture characteristics of environmental and social perspectives were applied in practice. Lastly, we have established experience data on social venture business model. This study focuses on the opinions, the meanings and the subjective views of the participants. As a result, conclusions are drawn by the researchers ' assertions and has limitations as a research on case studies. However, this study will help people who are preparing or studying social ventures to have economic, environmental, and social perspectives. Also, redefinition of the direction and value of entrepreneurs operating social ventures, such as vision and mission, will help clarify the roles and responsibility of organizations. As a fundamental step for future empirical studies, this study could be the base for social venture business model studies.

• Journal of Practical Engineering Education
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• v.15 no.1
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• pp.119-126
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• 2023

Today, in order to improve fuel efficiency and dynamic behavior of automobiles, an era of light weight and simplification of automobile parts is being formed. In order to simplify and design and manufacture the shape of the product, various components are integrated. For example, in order to commercialize three products into one product, product processing is occurring to a very narrow area. In the case of existing parts, precision die casting or casting production is used for processing convenience, and the multi-piece method requires a lot of processes and reduces the precision and strength of the parts. It is very advantageous to manufacture integrally to simplify the processing air and secure the strength of the parts, but if a deep and narrow pocket part needs to be processed, it cannot be processed with the equipment's own spindle. To solve a problem, research on cutting processing is being actively conducted, and multi-axis composite processing technology not only solves this problem. It has many advantages, such as being able to cut into composite shapes that have been difficult to flexibly cut through various processes with one machine tool so far. However, the reality is that expensive equipment increases manufacturing costs and lacks engineers who can operate the machine. In the five-axis cutting processing machine, when producing products with deep and narrow sections, the cycle time increases in product production due to the indirectness of tools, and many problems occur in processing. Therefore, dedicated machine tools and multi-axis composite machines should be used. Alternatively, an angle spindle may be used as a special tool capable of multi-axis composite machining of five or more axes in a three-axis machining center. Various and continuous studies are needed in areas such as processing vibration absorption, low heat generation and operational stability, excellent dimensional stability, and strength securing by using the angle spindle.

• Journal of Korean Ophthalmic Optics Society
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• v.11 no.3
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• pp.281-291
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• 2006

The aim of this study was performed the clinical test using Netspeg lens for good visual acuity on subjects with abnormal refraction status. The subjects of one hundreds adults (fifty males, fifty females, mean=21 years, range=19 to 24) were recorded. The subjects were researched the history including the systemic health, medication, genetics, allergy, systemic disease and ocular disease. The refraction test was recorded the monocular and binocular using objective method. Visual acuity was performed the binocular status using the Netspeg lens and CR-39. Stereopsis test was performed the titmus fly and TNO at near distance using Netspeg lens and CR-39. The P-VEP test was used the 16 pattern size(Bausch Lomb, production in USA) with three channels. Also Subjects viewed the p-vep stimulus with binocular vision through the corrected visual acuity using the Netspeg lens and CR-39. The contrast sensitivity test was performed the contrast sensitivity chart(pelli-Robertson, USA) at 1m distance using the Netspeg lens and CR-39. The ultrastructure of surface on the Netspeg lens and CR-39 was observed the SEM(JMS-5800, made in Japan). The results of this study was as follows: 1. In corrected visual acuity of abnormal refraction using the Netspeg lens and CR-39, the Netspeg lens wearer were acquired the good visual field and clear visual acuity comparative to CR-39 wearer in the subject vision test. however the comfort of visual acuity was similar results in the Netspeg lens and CR-39. Also the subjects of Netspeg lens wearer was good visual acuity more than CR-39 wearer and in the analysis of P-VEP, the amplitude of wave on Netspeg lens used appears to be better through the CR-39(p>0.5). Besides, on the contrast sensitivity, the Netspeg lens wearer was good results than CR-39. The value on stereopsis with TNO by Netspeg lens wearer was better than CR-39 in results. However, in the stereopsis test with Titmus, the Netspeg lens and CR-39 wearer was similar results. 2. The ultrastructure of Netspeg lens surface was the smooth and fine shape more than CR-39. Also, Netspeg lens have a fine line structure in ultrastructure. In conclusion, the results of this study conformed that the surface ultrastructure of Netspeg lens used is more specific pin hole design structure than CR-39. This study indicated that the vision of Netspeg lens used have a better than CR-39 in the corrected visual acuity for abnormal refraction eye. Therefore, In this paper, we suggested that the ultrastructure and line structure of Netspeg lens was related to good visual function. However the visual function of the aspheric Netspeg and ultra waterproof Netspeg lens was similar results.

• Journal of the Korean Institute of Landscape Architecture
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• v.46 no.1
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• pp.9-16
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• 2018

Landscape architecture is an indispensable professional service in building sustainable land and urban environments. The landscape architecture industry is closely related to the promotion of the health and welfare of the people, urban revitalization and residential environment improvement as well as job creation. Despite various public interest values of landscape architecture, the growth engine of the landscape architecture industry, which is supposed to improve the quality of landscape services, has stagnated. In 2015, the Landscape Architecture Promotion Act was enacted to provide a landscape architectural promotion facility and complex system to support revitalization through the integration of the landscape architecture industry. The purpose of this study is to suggest an improvement plan to enhance the effectiveness of the landscape architectural promotion facility and complex system. The results of the analysis are as follows: First, workers and experts in landscape architecture recognized the need for policies and projects to promote the landscape architecture industry. Second, the industrial types suitable for the landscape architectural promotion facility were landscape design, landscape maintenance and management, and landscape construction industry. Meanwhile the industrial types suitable for a landscape architectural promotion complex were landscape trees and landscape facilities production and distribution. Third, the expected effect of the designation of the landscape architectural facility was 'the increase of the business opportunity through the expansion of the network'. On the other hand, that of the landscape architectural promotion complex was 'the activation of various information sharing'. Fourth, 'the size of the local government landscape architecture industry and the capacity to cultivate' was the most important among the designation criteria of the landscape architectural promotion facility. As for that of the landscape architectural promotion complex, the 'feasibility of promotion plan' was the most crucial. Fifth, 'tax benefit and deductible exemption' was considered as a necessary support method for the activation of the landscape architectural promotion facility, and 'maintenance and management fee support' was recognized in the case of the landscape architectural promotion complex.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.22 no.6
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• pp.1210-1230
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• 1997

In this paper, we suggest an architecture of DS/CDMA tranceiver composed of one pilot channel used as reference and multiple traffic channels. The pilot channel-an unmodulated PN code-is used as the reference signal for synchronization of PN code and data demondulation. The coherent demodulation architecture is also exploited for the reverse link as well as for the forward link. Here are the characteristics of the suggested DS/CDMA system. First, we suggest an interlaced quadrature spreading(IQS) method. In this method, the PN coe for I-phase 1st channel is used for Q-phase 2nd channels and the PN code for Q-phase 1st channel is used for I-phase 2nd channel, and so on-which is quite different from the eisting spreading schemes of DS/CDMA systems, such as IS-95 digital CDMA cellular or W-CDMA for PCS. By doing IQS spreading, we can drastically reduce the zero crossing rate of the RF signals. Second, we introduce an adaptive threshold setting for the synchronization of PN code, an initial acquistion method that uses a single PN code generator and reduces the acquistion time by a half compared the existing ones, and exploit the state machines to reduce the reacquistion time Third, various kinds of functions, such as automatic frequency control(AFC), automatic level control(ALC), bit-error-rate(BER) estimator, and spectral shaping for reducing the adjacent channel interference, are introduced to improve the system performance. Fourth, we designed and implemented the DS/CDMA MODEM to be used for variable transmission rate applications-from 16Kbps to 1.024Mbps. We developed and confirmed the DS/CDMA MODEM architecture through mathematical analysis and various kind of simulations. The ASIC design was done using VHDL coding and synthesis. To cope with several different kinds of applications, we developed transmitter and receiver ASICs separately. While a single transmitter or receiver ASC contains three channels (one for the pilot and the others for the traffic channels), by combining several transmitter ASICs, we can expand the number of channels up to 64. The ASICs are now under use for implementing a line-of-sight (LOS) radio equipment.

• Journal of the Korean Institute of Landscape Architecture
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• v.36 no.6
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• pp.66-80
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• 2009

This paper attempts to investigate how the cultural phenomena associated with 'Wuyi-Doga(武夷棹歌)' and 'Wuyi-Gugok (武夷九曲)' was introduced to Joseon. The icon and code of 'Gugok' cultural text which was observed in the process of transmitting the culture through repetition and imitation were examined. With regard to research methodology, an 'analysis and discussion framework' was designed based on the literature review, field survey and the seven textuality criteria proposed by Dressier. Then the textuality of 'Wuyi-Gugok' was analyzed in terms of the dependent relation of text, the relationship between the creator and user, repetition, imitation and the spread process. Since ZhouHee(朱熙)'s 'Wuyi-Doga' and 'Wuyi-Gugok' were introduced to Joseon through literature and paintings, they became a part of the cultural Phenomena with unprecedented popularity. As a result, a great number of imitations can be found. In addition, governors would even take care of political affairs in a scenic mountain valley as described in this literature. Regardless of the writer's intentiot 'Gugok' settled in Joseon as new culture in harmony with Taoism and Sung COnfucianism. In other words, Joseon's Gugok-Wonlim(九曲園林) accepted the nature-appreciation aesthetic consciousness in 'Wuyi-Doga' and 'Wuyi-Gugok' on the basis of Taoism and Sung Confucianism. In terms of the text-based dependent relation only, however, the geographical coherence was somewhat loosened while the Gugok Culture that was dependent on Taoism or elegance in life dominated the internal structure of the textuality. Meantime, the internal factors that dominated the textuality of 'Wdyi-Gugok' were interpreted as 1) 'Aesthetics of Bending, Water Whirls', 2) 'Territoriality Expression Carve letters,' 3) 'Cultural Landscape seeing through the Speculation of Meaning,' 4) 'The Pursuit of Oddness and Presentationism' and 5) 'Transcendental Landscape of Taoism and Topos.'

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.32 no.4
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• pp.1-13
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• 2014

As part of reconsideration on naming of the scenic site No.1 "Myeongju Cheonghak-dong Sogumgang," this study attempts to identify whether there is any mistake with reference to place naming of Korea's No.1 scenic site and if so, to correct the problem by examining the origin of the name and its transition progress through analysis and interpretation of old maps, ancient documents such as traditional geographic books, Yusangi(遊山記) and Letters Carved on the Rocks. The findings of this study are as follows: In traditional geographic books, a term of 'Mt. Cheonghak(靑鶴山)' was first found from "SinjungDonggookyeojisungram(新增東國輿地勝覽)" and after a place name, 'Sogumgang(小金剛)' first appeared in "Yeojidoseo(輿地圖書)" in the middle of the 17th century, it was reproduced in "Jungsuimyeongji(增修臨瀛誌)", which was published in the early 20th century. However, as a result of analyzing old maps, the place name, Sogumgang cannot be found in any local or national map except place names such as Cheonghak-dong, Mt. Cheonghak and Temple Cheonghak. Even though 'Biseonam,' 'Cheonyudong,' 'Gyeongdam' and 'Mt. Cheonghak' appear in Yulgok's "Yucheonghaksangi(遊靑鶴山記)", any part in which 'Sogumgang' was referred is not found. Later, Cheonghak-dong Sogumgang seemed to had been called 'Mt. Cheonghak' or 'Cheonghak-dong(靑鶴洞)' for more than three centuries as seen in Lee Sun-il's "Godamilgo(孤潭逸稿)", Heo Geun's farewell records, Heo Mok's "Cheonghak-dong Guryongyeongi(靑鶴洞九龍淵記)", Yoon Sun-geo(尹宣擧)'s "Padongilgi(巴東日記)" and Lee Won-jo's letters and a poem composed by Gang Jae-hang in the middle of the 18th century is the only record in which the place name, 'Sogumgang' is shown. Meanwhile, 'Sogumgang' carved on Inung Rock(二能巖) in front of Temple Gumgang is presumed to be carved by Inunggyeoone(二能契員) in the 1870s or in 1930s, considering the size of each character, calligraphy, overall layout, wear extent and records in Jiriji. Therefore, no evidence can be found to say that each character of 'Sogumgang' was written by Yulgok because 'Sogumgang' has strong evidences of the origin of its place name. To sum up the findings stated above, since Yulgok's "Yucheonghaksangi", this place seems to have been referred as 'Mt. Cheonghak Cheonghak-dong' and as it is confirmed that the place name, 'Sogumgang' first appeared in "Ohyeongosijo(五言古時調)" of "Ibjaeseonsangyugo(立齋先生遺稿)" and "Yeojidoseo" in the middle of the 18th century, it can be inferred that the place name, Sogumgang had been partly mingled as an another name of Mt. Cheonghak. Therefore, even though it is difficult to say the existing place name has a significant problem, it is thought that it will be better to name 'Mt. Cheonghak Cheonghak-dong' rather than 'Cheonghak-dong Sogumgang' in order to stress on this place's traditional identity as a scenic site related to Yulgok. In addition, as confirmed in this study process, it is said that each character of place names, 'Mt. Cheonghak' and 'Gyeongdam(鏡潭)' and name 'Yoon Sun-geo' carved in Rock Sikdang stated in Yoon Sun-geo's "Padongilgi" in 1964 is a pledge showing the influence of "Yucheonghaksangi" as an ancient travel literature as well as a mark of the Giho school scholars' respect and spirit to honor Yulgok.

• Korean Journal of Food Science and Technology
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• v.37 no.2
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• pp.183-188
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• 2005

Effects of co-solvent polarity, citric acid, pressure, temperature, run time, and co-solvent ratio on extraction of major flavonoids from Lonicera Flos were investigated using supercritical fluid $CO_{2}(SF-CO_{2})$. HPLC analysis revealed addition of pure methanol resulted in low extraction yield of major flavonoids, luteoloin (Lu), Quercetin (Qu), Apigenin (Ap). Under same condition, as co-solvent polarity increased, yields of major flavonoids increased gradually, At optimum co-solvent extraction condirion of 60% aqueous methanol (10%, v/v), yields of Lu, Qu, and Ap were 42.09, 28.18, and 3.49 mg/100 g, respectively. Addition of citric acid to 60% aqueous methanol gave higher, with addition of 1% citrie acid resulting in highest yields of 63.2 (Lu), 39.35 (Qu), and 5.79 (Ap) mg/100 g. Optimum extraction conditions of major flavonoids were 200 bar, $50^{\circ}C$, 60 min, and $CO_{2}$-methanol-water(20: 1.8: 1.2).

• Journal of the Korean Institute of Landscape Architecture
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• v.43 no.4
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• pp.87-97
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• 2015

There's a trend towards vitalization of nightscape planning businesses nationally and locally as well for city image making and activation of regional economy, but there is still no systematic nightscape planning going on for lack of relevant researches and objective evaluations. This study aims to suggest the guideline for nightscape planning by conducting an eye tracking experiment and survey for recognizing the characteristics of a nightscape. Furthermore, the authors intended to verify the eye-tracking method as a tool for landscape evaluation. The research site was restricted in the campus of Virginia Tech, VA, and those were selected by experts' survey among various types of nightscape images. The variables for analyzing the characteristics of nightscape images selected were 'preference', 'safety(fear)' and 'clearness'. 'Fixation duration', 'saccade duration', 'scan path length', and 'pupil size' were selected as the eye movement measurements. The results of this study are as follows: The first outcome found was that there were significant differences among the characteristics(preference, safety and clearness) of a nightscape by MANOVA, and these variables were correlated positively by Pearson's correlation. Secondly, there were differences on fixation duration, saccade duration and scan path depending on the nightscape setting statistically. Also, the eye tracking measurement in an open setting was recorded lower than enclosed settings. In the result of a heat map, we found the meaning of the fixated areas on both viewing without intention and viewing intentionally. It turned out that the fixated areas were consistent with the areas the subjects felt preferred and clarity in all of the nightscape images, which means people usually focus on what they prefer and see clearly in a certain nightscape. Based on this result and previous studies, the authors could make a conclusion that eye tracking method can apply to evaluate nightscape settings in terms of analyzing the whole characteristics and finding specific points for the detailed analysis as well. Therefore, these results can contribute by suggesting nightscape planning, implication of the landscape evaluation, and implication of the eye tracking study.