• Title/Summary/Keyword: second order effects

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Effects of Surface Microstructure on Microwave Dielectric Properties of ZrO2-NiO added Ba(Zn1/3Ta2/3)O3 Ceramics (ZrO2와 NiO가 첨가된 Ba(Zn1/3Ta2/3)O3에서 표면 미세조직이 고주파 유전특성에 미치는 영향)

  • Kang, Sung-Woo;Kim, Tae-Heui;Moon, Joo-Ho;Kim, Sung-Youl;Park, Jun-Young;Choi, Sun-Hee;Kim, Joo-Sun
    • Journal of the Korean Ceramic Society
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    • v.45 no.11
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    • pp.701-706
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    • 2008
  • High frequency dielectric ceramics have potential for applications in mobile and satellite communications systems at frequencies higher than 10GHz. The Ba$(Zn_{1/3}Ta_{2/3})O_3$ ceramics are known to have a high quality factor, a small temperature coefficient of the resonance frequency and a high dielectric constant. On the other hands, sintering at high temperature for extended time is required to obtain the ordered structure for high quality factor. In this study, the microwave dielectric properties of $ZrO_2$ and NiO-added Ba$(Zn_{1/3}Ta_{2/3})O_3$ ceramics prepared by solid-state reaction have been investigated. Adding $ZrO_2$ and NiO could effectively promote the densification even the case of decreasing the sintering time. At the surface of samples, secondary phase of Ba-Ta compounds was formed possibly due to the evaporation of ZnO, however, the interior of the samples remained as pure Ba$(Zn_{1/3}Ta_{2/3})O_3$. The samples sintered at $1600^{\circ}C$ for 2h exhibited 1:2 ordering of Zn and Ta cations. Excellent microwave dielectric properties of $Q{\cdot}f$(>96,000 GHz) and ${\varepsilon}_r$=30 has been obtained.

PHENOLOXIDASE AND ANTIOXIDANT IN KOREAN GINSENG (고려인삼에 있어서의 페놀 산화효소의 항산화물질)

  • Park E.Y.;Luh B.S.;Branen A.L.
    • Proceedings of the Ginseng society Conference
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    • 1984.09a
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    • pp.257-275
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    • 1984
  • Enzymatic browning is considered desirable in tea and tobacco processing but undesirable in many fruits processing at the present time. It is necessary to understand the nature of the enzyme, phenoloxidase, in order to control browning reactions, and extend its effects to formation of browning products as antioxidants in ginseng. Ginseng exhibits antioxidant activity when incorporated with turkey dark meat patties. The activity in red ginseng showed about two times stronger than white ginseng. One of the phenolic antioxidants from fresh, white and reprocessed white ginseng was identified as phenol 2.6 Bis(1.1 dimethyl ethyl) 4-methyl among several unknown compounds by GC/mass spectrometer. In red ginseng, no phenol 2.6 Bis (1.1 dimethyl ethyl) 4-methyl was detected, the compound may be polymerized by phenoloxidase and form some higher molecular compounds which may possess high antioxidant activity. Phenoloxidase isozymes in fresh Korean ginseng (panax ginseng C.A. Meyer) were extracted with phosphate buffer at pH 7.3. The isozymes were purified through ammonium sulfate fractionation, dialysis and chromatography on a DEAE-cellulose column. Two groups of phenoloxidase were shown to be present, one in the floating agglomerated group and the other in the precipitate. group from the 0.85 saturation ammonium sulfate. The DEAE-cellulose column chromatography, the phenoloxidase isozyme present in the precipitate appears as the first peak (I), and that in the agglomerate in the second peak (II). Isozyme I showed higher activity with catechin and catechal, and isozyme II showed higher activity with p-cresol. The isozyme showed two optimum pH activity one at pH 4.5 and the other at 8.5 with catechin as substrate. Korean ginseng phenoloxidase has high heat stability. When heated at $75^{\circ}C$ for 2 hours, its activity remained $90\%\;and\;80\%$ on phenoloxidase I and II respectively. Phenoloxidase I was most active on (+) catechin followed by p-cresal, catechol and epicatechin. Phenoloxidase II was most active on p-cresal followed by (+) catechin, catechol, p-coumanic acid and epicatechin. Sodium bisulfite, sodium cyanide, ascorbic acid glutachion in the oxidized form, sodium diethyl dithiocarbomate and ethylendiamine tetra acetate (EDTA) acted as inhibitors. Red ginseng color development was initiated by phenoloxidase and finished by a followed sun drying process. The antiaging activity of ginseng may be initiated by the antioxidant in the ginseng.

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The Structural Relationships among the Related Variables of University Students' Satisfaction (대학생의 만족도와 관련된 변인들 간의 구조적 관계)

  • Son, Kyung-Ae;Lee, Deog-Ro
    • Management & Information Systems Review
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    • v.32 no.4
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    • pp.1-25
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    • 2013
  • The purpose of this study was to test the structural relationships among the related variables of university students' satisfaction. This study utilized nation-wide survey data previously collected from 1400 students distributed across 32 universities in Korea. NCSI model was used as a theoretical framework. Using the AMOS 17.0, the structural relationships among six variables were tested, including students' expectancy level, perceived quality, perceived value, satisfaction, complaint rate, and loyalty. The major findings of the study are as follows: First, students' expectancy level had a positive effect on perceived quality; but had no significant effect either on perceived value or on satisfaction. Second, perceived quality had positive effects on perceived value and satisfaction; and perceived value also had a positive effect on satisfaction. Third, students' satisfaction had a negative effect on complaint rate; but had a positive effect on loyalty. Fourth, students' complaint rate had a negative effect on loyalty. The study results imply that among the related variables of students' satisfaction, perceived quality and value of the products work as critical variables, and complaint rate and loyalty directly relate to students' satisfaction. The study suggested that in order to enhance students' satisfaction, universities employ the total quality system and the students' complaints resolution system.

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PMO Theory of Orbital Interactions (Ⅳ). n-n Orbital Interactions in Some Heteroatom Systems (궤도간 상호작용의 섭동분자궤도 이론 (제4보). 헤테로 원자계에서의 n-n 궤도간 상호작용)

  • Ikchoon Lee;Chang Kook Sohn;Wang Ki Kim
    • Journal of the Korean Chemical Society
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    • v.27 no.5
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    • pp.330-339
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    • 1983
  • The CNDO/2 and STO-3G calculations were performed on nitrogen, oxygen, and sulfur compounds in order to examine the effect of interactions between two nonbonding (n) orbitals in the same molecule separated by N intervening $\sigma$ bonds based on the PMO approach. Calculated basis level energies, energy splittings, and interaction energy changes for both chain and cyclic model compounds were qualitatively compared with the corresponding predictions derived from perturbational formalism for n-n orbital interactions and successfully explained in terms of the derived energy expressions. In general, through-space interaction term could be neglected in the N and O systems. And the calculated results were explained simply by through-bond interaction term. As a result, through-bond interaction placed n- below n+ for odd systems and n+ below n- for even systems. Also energy splittings in odd systems were larger than those in even systems. However, in the cases of cis-ethylene diamine and o-phenylene diamine(conformer VI in Table 4), through-space interaction term was found to be substantial and the opposing effects of through-space and through-bonds interactions were observed. Finally it was found that the interactions between two n orbitals on S atoms always had some contribution of the destabilizing through-space interaction term. This result was consistent with the fact that the lone pair lobes of third elements were larger in size than those of the second period elements.

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The Effects of Social Capital and Acculturation Stress on School Adaptation of Adolescents of Multi-cultural Family (다문화가족 청소년의 사회적 자본 및 문화변용스트레스가 학교적응에 미치는 영향)

  • Jeon, Byeong-Joo
    • Journal of Digital Convergence
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    • v.10 no.11
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    • pp.29-38
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    • 2012
  • This study conducted a survey 185 adolescents in multi-cultural family to measure the level of their social capital and their acculturation stress and examined how it affects them to adapt to school. Followings are the main results of this study. First, after measuring the social capital level of those surveyed, their average was lower than the normal level, showing 2.24(SD=.32), and their acculturation stress showed 2.54(SD=.58), a bit higher than the normal level. Second, their level of adapting to school showed 2.26(SD=.39), which was lower than the normal level, and there was statistically a meaningful difference between the groups depending on their grade, academic level, economic level, parents' marital status, mother's Korean ability. Third, the factors that affected in adapting to school were in the order of their network of social capital(${\beta}$=.225), mother's Korean ability(${\beta}$=.195), acculturation stress(${\beta}$=-.175), interpersonal trust of social capital(${\beta}$=.171), norm of social capital(${\beta}$=.161), parents' marital status(${\beta}$=.156), academic level(${\beta}$=.151), economic level(${\beta}$=.145). Based on these results, this study suggest ways to promote trust building among people and network formation through active use of information communication, and to improve multi-cultural acceptability by developing and using various contents.

Impact of Instrumental Factors on Dissatisfaction and Complaint Behaviors: Moderating Role of Expected Profitability (프랜차이즈 가맹본부의 도구적 요인이 가맹점의 불만족 및 불평행동에 미치는 영향: 기대 수익성의 조절효과)

  • Kim, Eun-Jung;Ju, Mi-Ja;Lee, Yong-Ki
    • Journal of Distribution Science
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    • v.14 no.9
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    • pp.95-110
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    • 2016
  • Purpose - Based on expectation-disconfirmation theory, this study attempted to fill the gap in the literature by treating the expected profitability as a moderator in the relationship between these constructs, identifying what instrumental factors have effects on dissatisfaction, in turn lead to exit intention, neglect, voice, and loyalty, and provide the managerial implications for building long-term relationship to enhance the partnership between franchisor and franchisee. Research design, data and methodology - In order to test the hypotheses, the authors developed several hypotheses. The data were collected from 254 franchisees in Seoul and Gyeonggi Province with SPSS 18.0 and SmartPLS 2.0. Results - The findings of the study are as follows. First, marketing support and competitiveness of product and service had a negative effect on dissatisfaction, but did not on logistics support. Second, franchisee dissatisfaction had a positive effect on exit intention and neglect, and had a negative effect on loyalty. However, franchisee dissatisfaction had not a significant effect on voice. Third, expected profits play a moderating role in the relationships between marketing support, competitiveness of product and service and dissatisfaction, between dissatisfaction and exit intention, voice, loyalty, and neglect. First, marketing support and competitiveness of product and service were found to have a greater influence on dissatisfaction for the low expected profitability group than the highly expected profitability group. Also, dissatisfaction had a greater impact on exit intention, voice, and neglect for the low expected profitability group than the high expected profitability group while dissatisfaction had a weaker impact on loyalty for high expected profitability group. Conclusions - The result of this study indicates that franchisors should reduce dissatisfaction and prevent or improve complaint behaviors by continuously identifying the impact relationship between franchisee dissatisfaction and decision factors caused by difference in expectations for roles of franchisees and franchisors. In addition, franchisors should acknowledge that the impacts of marketing support, and product and service competitiveness on franchisee dissatisfaction and on exit intention, neglect, and loyalty differ by expected profits. Therefore they should provide support in perceiving high expected profits through creating direct profits including high sales, low costs, and low rents.

Perceived Innovation Attributes and Acceptance of Chatbots as Determined by Consumer Characteristics (소비자 특성에 따른 챗봇의 인지된 혁신속성과 혁신수용)

  • JUNG, Jaehwan;BYUN, Sangwoon;KIM, Mi-Sook
    • The Journal of Industrial Distribution & Business
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    • v.10 no.7
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    • pp.39-48
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    • 2019
  • Purpose - The purpose of this study was to explore the impact of chatbots' innovation attributes on the innovation acceptance for consumers who have used chatbots to purchase fashion products that account for a large share of transactions in mobile shopping. Research design, data, and methodology - Data were collected from Korean consumers aged 20 to 49 who had experience using chatbots when purchasing fashion-related products via mobile circumstances. After a pilot survey of 31 customers, pre-questionnaire was revised for the final test, and the final questionnaire was distributed to 1,500 subjects. Out of these, 244 were retrieved. After excluding 48 inappropriate responses, 196 were used for statistical analysis. Frequency analysis, exploratory factor analysis, one-way ANOVA, regression analysis and independent t-test using SPSS 23.0 were employed for data analyses. Results - First, four factors of chatbots' attributes were extracted: relative advantages and compatibility, complexity, sensibility, and diversity. Second, two factors were extracted for fashion leadership: fashion opinion leadership and fashion innovativeness. Two groups based on the fashion leadership were identified: active innovation adopters and passive innovation adopters. Third, relative advantages and compatibility, diversity, sensibility of innovation attributes were found to have effects on the innovation acceptance in order. Fourth, significant differences were found in sensibility of innovation attributes and innovation acceptance in groups by marital status and age. The married in their 30s and 40s perceived sensibility as a more important attribute of chatbots than the unmarried in their twenties. Among the groups of different income levels, meaningful differences were found in diversity of innovation attributes and innovation acceptance. Fifth, there were significant differences found in relative advantages and compatibility, sensibility of innovation attributes, and acceptance of Innovation among the groups by fashion leadership. Active innovation adopters were found to be more aware of the importance of relative advantages and compatibility, and sensibility of innovation attributes, and innovation acceptance. Conclusions - The present study provides chatbots' marketing strategies for fashion items need to be modified by demographic characteristics and fashion leadership. Particularly, fashion leadership was found to be an important factor in determining the perception of innovation attribute as well as innovation acceptance.

Optimization for Electron Donating Ability and Organoleptic Properties of Ethanol Extracts from Chrysanthemum Petals (전자공여작용과 관능적 특성을 고려한 산국(山菊) 에탄올 추출물의 제조조건 최적화)

  • Park, Nan-Young;Lee, Gee-Dong;Jeong, Yong-Jin;Kim, Hyun-Ku;Kwon, Joong-Ho
    • Korean Journal of Food Science and Technology
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    • v.30 no.3
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    • pp.523-528
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    • 1998
  • Response surface methodology (RSM) was used to monitor extraction characteristics of electron donating ability and organoleptic properties for ethanol extracts from Chrysanthemum petals, thereby determining optimum extraction conditions. A central composite design was applied to investigate effects of solvent per sample $(X_1)$, ethanol concentration $(X_2)$ and extraction time $(X_3)\;at\;60^{\circ}C$ on dependent variables such as electron donating ability $(Y_1)$, organoleptic color $(Y_2)$ and organoleptic aroma $(Y_3)$ of the extracts. Second-order models were employed to generate 4-dimensional response surfaces for qualitative and quantitative aspects of ethanol extracts. Coefficients of determination $(R_2)$ of the models for dependent variables were ranged from 0.8180 to 0.9696. Optimum extraction conditions for each variable were 50 mL/g, 61% and 16 hrs in electron donating ability, 88 mL/g, 21% and 16 hrs in organoleptic color, 55 mL/g, 73% and 19 hrs in organoleptic aroma, respectively. The optimum condition ranges for maximized characteristics of ethanol extracts were $65{\sim}78\;mL/g,\;90{\sim}100%\;and\;15{\sim}25\;hrs$. Predicted values at the optimum conditions were in good agreement with experimental values.

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The Effects of Transformational Leadership on Job Satisfaction and Job Performance: Focused on Deluxe Hotel Culinary Staff (변혁적 리더십이 직무만족 및 직무성과에 미치는 영향 - 특급호텔 조리사를 중심으로 -)

  • Ryu, Ji-Yong;Park, Ji-Soo;Park, Ki-Bong
    • Culinary science and hospitality research
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    • v.19 no.3
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    • pp.194-208
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    • 2013
  • This study presented a theoretical research system about the impact of boss' transformational leadership that is recognized by super luxury hotel chefs on their job satisfaction and performance, and on the basis of this theoretical background, the model was derived and the hypothesis was confirmed by empirical research. A frequency analysis was conducted to determine the general characteristics of the 245 samples collected in this study, an exploratory factor analysis for the verification of the validity of boss' transformational leadership, employees' job satisfaction and job performance, and 'Cronbach's a' was used for the verification of reliability. In addition, a canonical correlation analysis was used to determine the relationship between transformational leadership, job satisfaction and job performance, and the influencing relations of variables were verified by running a multiple regression analysis through SPSS ver 18.0 statistical package in order to verify this research model and hypothesis. The results of this study can be summarized as follows: First, it was shown that the transformational leadership charisma (p<0.01) and only the individual concern (p<0.1) had a positive influence on job satisfaction. Second, as a result of understanding the impact of the transformational leadership on the job performance through a regression coefficient, it was shown that only boss' intellectual stimulation had an impact on the chef's job performance (p<0.005). Through the results of an empirical analysis that boss' transformational leadership had a correlation and a significant impact on job satisfaction and job performance, the effort of providing the systematic support and motivational aspects of supporting environment will be needed.

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Development and Evaluation of Home Economics Maker Education Program for High School Students: Focusing on the Contents of 'Hanbok and Creative Clothing' (고등학교 가정과 메이커 교육 프로그램 개발과 평가: '한복과 창의적인 의생활' 내용 요소를 중심으로)

  • Kim, Saetbyeol
    • Journal of Korean Home Economics Education Association
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    • v.31 no.4
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    • pp.63-79
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    • 2019
  • The purpose of this study was to suggest valuable maker education programs by implementing and evaluating a Home Economics(HE) maker education program developed based on the content of "Hanbok and Creative Clothing" for high school students. The results of this study are as follows. First, the HE maker education model for high school students was designed and developed. The HE maker education model was developed by integrating and modifying the TMSI model of the maker education model and Laster's HE practical action teaching model. The HE maker education model consisted of 4 steps: tinkering(T: 4-hour class), practical reasoning(P: 3-hour class), making together(M: 4-hour class), and sharing and spreading(S: 1-hour class) with a total of 12-hour lesson plans. The theme of the developed HE maker program is 'Practice and spread of creative traditional culture of life (Hanbok)'. Second, the results of online survey of 240 high school students who participated in this maker class showed that HE maker class had positive effects in the order of experiential(4.26), cognitive(4.22), emotional(4.18), social(4.18), and practical(4.10). It is expected that the findings of this study will contribute to diversifying the curriculum of Home Economics, thereby improving the quality of Home Economics Education.