• Journal of the Korean Wood Science and Technology
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• 제41권6호
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• pp.583-593
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• 2013

본 연구는 크라프트 리그닌의 염기 촉매 분해(Based Catalyst Depolymerization, BCD)반응에서 생성되는 반응물의 화학적 특성을 조사하였다. 초임계 메탄올을 용매로 하고 염기 촉매로 사용한 NaOH의 농도를 7.5, 3.25, 6.13%로 변화를 주었다. BCD 반응물에서 불용성 고형 부산물, 수용성 부산물과 각 부산물에서 diethyl ether로 추출하여 DEE-1, DEE-2를 얻었고 그 화학적 조성을 분석하였다. 실험 결과 염기의 농도가 높아질수록 불용성 고형 부산물이 많이 생성된 반면 수용성 분액분의 수율은 낮아졌으나 DEE 추출분의 수율은 차이가 없었다. 불용성 부산물에서 추출한 DEE-1은 GC/MS 분석 결과 BHT외에 페놀성 화합물은 검출되지 않았다. 대부분의 저분자 리그닌 분해 산물은 DEE-2에서 GC/MS를 사용하여 30개 이상의 피크가 관찰되었고 21개 성분이 확인되었다. 7.5와 3.25%의 NaOH를 사용한 반응의 DEE-2 주성분은 catechol (20.3, 17.7%), 4-methylcatechol (18.2, 15.6%), 3-methoxycatechol (9.6, 14.5%), syringol (8.9, 10.9%)등으로 주로 catechol 계열의 화합물이었다. 1.63%의 NaOH를 사용한 반응의 DEE-2 주성분은 syringol (22.3%), isovanillic acid (12.6%), 3-methoxycatechol(12.1%), 4-methylcatechol (11.7) 등으로 나타났다. 염기의 농도가 저분자 페놀성 화합물들의 전체적인 수율에는 영향이 없었지만 3.25와 1.63%의 농도를 경계로 성분 조성에 큰 영향을 주는 것을 관찰할 수 있었다.

• 인삼문화
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• 제6권
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• pp.13-34
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• 2024

The abolishment of the red ginseng monopoly act by the Korean government in 1996 resulted in a drastic change in the Korean ginseng industry, leading to a significant increase in the market size and consumption of ginseng products. Red ginseng is most popular type, with approximately 74% of harvested fresh ginseng being processed into various red ginseng products. Since 1997, there has been a substantial increase in the cultivation of ginseng for production of red ginseng, which, in turn, has contributed to the proliferation of ginseng processing companies. To investigate the products of ginseng manufacturing businesses, we select 200 companies primarily engaged in ginseng processing or specializing solely in ginseng. Our survey on the status of ginseng industry covered 8 different categories. 1) Root ginseng: There were 66 companies involved in manufacturing red ginseng root, accounting for 33.0% of all surveyed companies. This was followed by black ginseng root with 36 companies (18.0%) and red ginseng fine roots with 22 companies (11%). 2) Red ginseng products: A total of 144 companies were involved in manufacturing red ginseng pouches, making it the most common product category. This was closely followed by 142 companies producing pure(100%) red ginseng extract concentrate. 3) Fermented red ginseng products: Companies producing fermented red ginseng extract concentrate products were the most numerous, totaling 26. Following this, companies producing fermented red ginseng stick and pouch products were next in line. 4) Ginseng products: There were 15 companies involved in the production of ginseng products, with the majority focusing on ginseng tea. 5) Black ginseng products: Companies producing black ginseng extract concentrate were the most numerous, with 31 companies, followed by 26 companies producing black ginseng extract pouches. 6) Taegeuk ginseng products: Only 5 companies were involved in the production of taegeuk ginseng products. 7) Fermented black ginseng, and 8) Ginseng berry products: These categories are manufactured by less than 5 companies each. However, the variety in ginseng berry products suggests the potential for future growth. In the 2000s, a trend emerged with the development of new processed products aimed at enhancing the functional components of red ginseng, and these products have captured the attention of consumers. However, this study primarily focuses on black ginseng, fermented red ginseng/fermented black ginseng, and ginseng berry products as they have exerted a significant influence on the overall ginseng industry.

• 터널과지하공간
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• 제8권1호
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• pp.8-16
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• 1998

The first purpose of this study is to verify the application of computer modelling to a enclosed space fire. The second one is to determine temperature distribution for the three different ventilation types in case of a enclosed space fire. The third one is to find out the ventilation direction and ventilation quantity to remove effectively heat and combustion products generated by a fire in variable air volume(VAV) system. Firstly, compared with experimental results of Lawrence Livermore National Laboratory(LLNL), numerical results show good agreements. Secondly, among three different ventilation types, the numerical analyses show the highest temperature distribution in occupied zone(up to 1.8 m from bottom) from firing moment to 100 sec. when supply ducts are placed in ceiling and extract duct is placed close to the bottom on side walls. This is due to disadvantageous position of extract duct in ventilating high temperature air which rise because of buoyancy force. Thirdly, this study finds out effective ventilation direction and ventilation quantity to remove heat and combustion products generated by a fire by using VAV system. $CO_2$ concentration is used as a fire fume removal index. As soon as a fire happens, ventilation direction is changed in order to gather and drive out fire fumes. In case of three times ventilation quantity of ordinary one, $CO_2$ concentration and temperature have begun to decrease at 120 sec. after firing, i.e.fire fumes have begun to be removed.

• Journal of the Korean Wood Science and Technology
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• 제44권6호
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• pp.872-879
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• 2016

Demand of natural interior finishing material has been widely sprayed in nowadays because many weak people as children, pregnant women, and elder people are being struggled with sick house syndrome due to volatile organic compounds such as formaldehyde, toluene, benzene, etc. Our research group developed a no-added formaldehyde adhesive for wood-based panels from mainly rice powder and some additives in the previous study for abating sick house syndrome. Since the rice powder adhesive provides a good source of nutrients with microorganisms, it was suspected a susceptibility of the rice powder adhesive to fungal and sapstain attack. We evaluated anti-sapstain activity of the rice powder adhesives modified by adding wood preservatives. We modified the rice powder adhesive by adding three different types of anti-sapstain preservatives at three different concentrations to assess their anti-sapstin activity. The bonding strengths of the modified rice powder adhesives were still outstanding performance on all samples. Moreover, the plywood manufactured with the modified rice powder adhesive satisfied outdoor use requirement for ordinary plywood (KS F3101, Korean Standard). The results obtained showed that at least 3% of preservative should be added to the rice powder adhesive to obtain effective anti-sapstain activity.

• 한국대기환경학회지
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• 제22권1호
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• pp.145-151
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• 2006

As the concerns about indoor air quality (IAQ) increase in recent years, lots of research works are under way to investigate the influence of volatile organic compounds (VOCs) emitted from building products on the IAQ. One of the regulations for the IAQ is the level of total VOCs (TVOCs) from building products, assuming that the TVOCs are suspected to cause many health problems such as skin irritation, asthma, and allergy. However, the presence of biogenic VOCs, or natural VOCs (NVOCs) is believed to be beneficial to human health. Therefore, this study attempted to investigate chemical species and the NVOCs compositions of solid lumbers from different wood species. It was found that major VOC components were monoterpenes such as $\alpha$-pinene, $\beta$-pinene, d-limonene, camphene, $\alpha$-terpinene, $\gamma$-terpinene etc.

• 유통과학연구
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• 제16권10호
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• pp.47-54
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• 2018

Purpose - The main purpose of the study is to investigate the antecedents of repurchase intention on foreign brand products by Chinese and Indian millennial customers. In addition to this, this study also examines mediating effect of 'CSR' on the relationship between the antecedents and repurchase intention. Research design, data, and methodology - Responses from 202 Chinese university students and 209 Indian university students were finally analyzed. To test the proposed relationships, path analyses, mediation analyses and multi-group analysis were conducted. Results - In China, only brand image had positive effects on repurchase intention. CSR played mediating role between manufacturer's country image and repurchase intention. In India, comparatively, economic factor, manufacturer's country image and brand image had positive effects on repurchase intention. CSR played mediating role between all four antecedents and repurchase intention. Conclusion - This study showed different results of repurchase intentions of Millennial consumers in China and India because cultural and political systems of two countries were so different. So foreign firms should apply customized and differentiated marketing strategies to each country.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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• pp.397-400
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• 2004

Synthetic Aperture Radar(SAR) is an active micro­wave instrument that performs high-resolution observation under almost all weather conditions. Although there are many advantages of SAR instrument, many complicated steps are involved in order to generate SAR image products. Many research and algorithms have been proposed to process radar signal and to increase the quality of SAR products. However, it is hard to find research which compare the quality of SAR products generated with different algorithms and processing methods. In our previous research, a SAR processing s/w was developed for a ground station. In addition, quality assessment procedures and their test parameters inside a SAR processor was proposed. The purpose of this paper is to evaluate the quality of SAR images generated from the developed SAR processing s/w. However, If there are no direct measurements such as radar reflector or scattering field measurement values it is difficult to compare SAR images generated with different methods. An alternative procedures and parameters for SAR image quality evaluation are presented and the problems involved in the comparison methods are discussed. Experiments based on real data have been conducted to evaluate and analyze quality of SAR images.

• 대한인간공학회지
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• 제29권3호
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• pp.287-296
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• 2010

The purpose of this research is to analyze priority of the elderly user interface (UI) evaluation criteria based on user's lifestyle. Since the elderly population will occupy over 20% of the all Korean population in the near future, we need to know older users' needs and information because elderly users will be main customers in the super-aged society. This paper investigated the definition of elderly users and characteristics demographically, socio-economically, and physically/cognitively. A total of 238 questionnaires from older users were analyzed based on a segmentation table for the elderly developed by the previous study. According to factor analysis and cluster analysis, 6 types of lifestyle and 4 groups of the elderly users were classified, respectively. The priority of UI evaluation criteria for large electronic home appliances and mobile products was analyzed by analyses of variance (ANOVAs). The results indicated that the priority of (physical, emotional, and cognitive) UI criteria was significantly different among elderly users' lifestyles for both home appliances and mobile products. Consequently, the results of this study may help the company develop some competitive silver products and give higher satisfaction to the elderly users by suggesting different priority of UI evaluation criteria according to the target elderly group. The results may also contribute to revitalize national economy by significantly increasing senior market shares.

• 유통과학연구
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• 제16권1호
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• pp.7-15
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• 2018

Purpose - This study aimed to identify the impact of consumers' perception of the value of discount store PB products on brand loyalty and repurchase intention and simultaneously check whether consumers showed a different position depending on gender difference and age. Research design, data, and methodology - For data collection, total of 174 valid copies of questionnaire were obtained for analysis. And simple regression, multiple regression and hierarchical moderated regression analysis was conducted for hypothesis verification and implication Results - It was found that functional, social and emotional value perceived by consumers had a positive impact on brand loyalty and repurchase intention. And it was found that consumers who were in a relatively lower age group were positive, in the relation between emotional value and repurchase intention only. Conclusions - It was suggested that consumers accept discount store PB products positively overall. Therefore, discount stores must not only need to develop their strengths in various parts of PB product beyond consumer's positive perception but also make efforts to raise the social awareness of the use of PB products. And they have to promote consumer decision making by concentrating on emotional factors take a different approach to consumers in a higher age group.

• 대한기계학회논문집A
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• 제32권11호
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• pp.1010-1015
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• 2008

In this study, the characteristics of aluminum tube hydroformed products at different extrusion type and heat treatment conditions were investigated. For the investigation, as-extruded, full annealed and T6-treated Al 6061 tubes at different extrusion type were prepared. To evaluate the hydroformability, free bulge test was performed at room temperature to $300^{\circ}C$. Also mechanical properties of hydroformed products at various pre- and post-heat treatments were estimated by hexagonal prototype hydroforming test at $250^{\circ}C$. And the tensile test specimens were obtained from hexagonal prototype hydroformed tube. As a results, hydroformability of full annealed tube is $5{\sim}8%$ higher than that of extruded and T6-treated tube. The tensile strength and elongation of T6-post heat treated indirect extrusion tube were more than 330MPa and 12%, respectively. However, T6 pre treated hydroformed product represents high strength, 330MPa and low elongation, 8%. Therefore, Hydroformability of Al6061 tube showed similar value for both extrusion types. However flow stress of direct tube showed $20{\sim}50MPa$ lower value than indirect tube.