• Title/Summary/Keyword: second order effects

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Adsorption Characteristics of Bisphenol A Using Activated Carbon Based on Waste Citrus Peel and Surface-Modified with P2O5 (P2O5로 표면 개질한 폐감귤박 활성탄에 의한 Bisphenol A의 흡착 특성)

  • Kam, Sang-Kyu;Kim, Myeong-Chan;Lee, Min-Gyu
    • Journal of Environmental Science International
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    • v.27 no.11
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    • pp.1095-1104
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    • 2018
  • The adsorption characteristics of bisphenol A (BPA) were investigated using activated carbon based on waste citrus peel (which is abandoned in large quantities in Jeju Island), denoted as WCP-AC, and surface-modified with various $P_2O_5$ concentrations (WCP-SM-AC). Moreover, coconut-based activated carbon (which is marketed in large amounts) was surface-modified in an identical manner for comparison. The adsorption equilibrium of BPA using the activated carbons before and after surface modification was obtained at nearly 48 h. The adsorption process of BPA by activated carbons and surface-modified activated carbons was well-described by the pseudo second-order kinetic model. The experimental data in the adsorption isotherm followed the Langmuir isotherm model. With increasing $P_2O_5$ concentration (250-2,000 mg/L), the amounts of BPA adsorbed by WCP-SM-AC increased till 1,000 mg/L of $P_2O_5$; however, above 1,000 mg/L of $P_2O_5$, the same amounts adsorbed at 1,000 mg/L of $P_2O_5$ were obtained. With increasing reaction temperature, the reaction rate increased, but the adsorbed amounts decreased, especially for the activated carbon before surface modification. The amounts of BPA adsorbed by WCP-AC and WCP-SM-AC were similar in the pH range of 5-9, but significantly decreased at pH 11, and increased with increasing ionic strength due to screening and salting-out effects.

A Study on the Usability Evaluation of the Archival Contents in the National Archives of Korea: Focus on "Decisions Relating to the Independence Movement" Collection (국가기록원 기록정보콘텐츠의 사용성 평가에 관한 연구: '독립운동관련 판결문' 컬렉션을 중심으로)

  • Yu, Eun Yeong;Kang, Soon Ae
    • Journal of Korean Society of Archives and Records Management
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    • v.19 no.1
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    • pp.137-166
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    • 2019
  • The study aims to determine the areas and elements of usability evaluation that reflect the characteristics of the archival contents collections in the National Archives of Korea, and to evaluate the usability of the "Decisions Relating to the Independence Movement" collection for history majors. Through the findings, the relation and importance level that usability evaluation areas and elements have on overall satisfaction can be identified. As a result of this study, the areas of content, search, and interface all had positive effects on overall satisfaction. The interface area holds the greatest influence, and the two elements on each area were found to have a positive effect. On the other hand, users selected the order of importance as "search" first, "contents" second, and "interface" third, showing that interface was considered relatively less important. Based on this, we propose improving the usability direction of the archival contents collection of the National Archives of Korea.

The Effect of Customer Orientation on Customer Loyalty and Organizational loyalty Mediated by Ethical and Discretionary Responsibility (고객지향성이 윤리적 책임과 재량적 책임을 매개로 고객충성도와 조직충성도에 미치는 영향)

  • Cha, SuJin;Hwang, Kumju
    • Journal of Digital Convergence
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    • v.16 no.11
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    • pp.201-209
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    • 2018
  • This study seeks to examine the effect of customer orientation on customer loyalty and employee loyalty mediated by two dimensions of corporate social responsibility (CSR), discretionary and ethical dimensions. This study examined the effects of customer orientation on discretionary responsibility and ethical responsibility. Additionally, it examined the effect of discretionary responsibility and ethical responsibility on customer loyalty and organizational loyalty. In order to verify the hypothesis, we surveyed the employees of large companies and analyzed 239 valid data. First, customer orientation has a significant positive impact on discretionary responsibility. Second, customer orientation has a significant positive impact on ethical responsibility. Third, discretionary responsibility has a significant positive impact on customer loyalty. Fourth, discretionary responsibility has a significant positive impact on organizational loyalty. However, ethical responsibility does not predict customer loyalty and organizational loyalty. Theoretical and practical implications of the results of this study, limitations and directions for future research are discussed.

Development and Application Effect of Entrepreneurship Education Program for Teachers (창업 교육 역량 강화 프로그램 개발 및 적용 효과)

  • Baek, MinJung;Kang, Kyoung-Kyoon;Yoon, Eunjin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.19 no.12
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    • pp.532-540
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    • 2018
  • The purpose of this study is to develop a training program for teachers to improve their entrepreneurial education competency for teenager entrepreneurship education. In order to achieve this objective, the training program was developed through a literature review and input from professionals. In addition, to verify field appropriateness of the entrepreneurship program for teachers, teachers participated in the program and a satisfaction survey was conducted. Results of this study are as follows. First, this study developed teaching contents and methods for entrepreneurship education which included 4 hours of online education and 26 hours of off-line education, for a total of 30 hours. Second, for verifying the applicability to schools and its effects, the satisfaction of training was examined using 88 teachers that participated in the entrepreneurship education program. Results found the satisfaction level was rated 4.58 for the curriculum suitability and 4.67 for the effectiveness of class contents, indicating that teachers were very satisfied with the training program and contents.

KTX passenger demand forecast with multiple intervention seasonal ARIMA models (다중개입 계절형 ARIMA 모형을 이용한 KTX 수송수요 예측)

  • Cha, Hyoyoung;Oh, Yoonsik;Song, Jiwoo;Lee, Taewook
    • The Korean Journal of Applied Statistics
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    • v.32 no.1
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    • pp.139-148
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    • 2019
  • This study proposed a multiple intervention time series model to predict KTX passenger demand. In order to revise the research of Kim and Kim (Korean Society for Railway, 14, 470-476, 2011) considering only the intervention of the second phase of Gyeong-bu before November of 2011, we adopted multiple intervention seasonal ARIMA models to model the time series data with additional interventions which occurred after November of 2011. Through the data analysis, it was confirmed that the effects of various interventions such as Gyeong-bu and Ho-nam 2 phase, outbreak of MERS and national holidays, which affected the KTX transportation demand, are successfully explained and the prediction accuracy could be quite improved significantly.

Analysis of Health Status of Street Trees and Major Affecting Factors on Deogyeong-daero in Suwon (수원시 덕영대로의 가로수 건강성 평가 및 주요 영향요인 분석)

  • Kim, Eun-Young;Jung, Kyung-Min
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.22 no.2
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    • pp.49-57
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    • 2019
  • The street trees increase the liveability of cities by reducing stormwater runoff, improving air quality, storing carbon, providing shade, and ameliorating the urban heat-island effect. In this study, the health status of street trees in Suwon was evaluated, and the factors affecting the growth of the trees were also derived. In order to evaluate the growth and health of street trees, field survey was carried out on a total of 125 trees in 25 sections of the Deogyeong-daero where is through the city. During the field survey, the following items were examined: Street trees health status (i.e. species, height, DBH (diameter at breast height), planting types, vigor, etc.), soil factors (i.e. soil temperature, humidity, pH, hardness, etc.), and environmental factors (i.e. landuse, road width, etc.). As the results of field survey, the main species of the street trees was Zelkova serrata, which was healthy in most of the sections. The factors such as planting types, soil temperatures, tree root cover, road extension, distance from the road were derived to affect the growth and health of street trees, and the differences were significant. The results of this study were derived the following conclusions for vigorous street trees: First, it is important to install and maintain the protection facilities like tree root cover for the growth of trees. Second, it is necessary to discuss how to plant multiple trees in narrow spaces like a street green space. Third, it is important to provide appropriate soil conditions continuously for growth of threes. Finally, it should be utilized as a mitigation measure of urban heat island effects.

Effectiveness of whole body vibratory stimulation for fall prevention in super-aged women: a preliminary randomized trial

  • Kim, Byeong-Soo;Lim, Kang-Uk;Baek, In-Seon;Kim, Min-Kyoung;Kang, Hye-Min;Nam, Gi-Jeong;Lee, Myung-Mo
    • Physical Therapy Rehabilitation Science
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    • v.8 no.1
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    • pp.32-39
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    • 2019
  • Objective: The aim of this study is to investigate the effects of whole body vibratory stimulation on muscle strength, balance, and fall efficacy among super-aged women. Design: Randomized controlled trial. Methods: Twenty-eight super-aged women over 80 years of age were assigned to either the experimental group (n=14) and control group (n=14). The experimental group received an exercise program that used the whole body vibratory stimulation with a frequency of 30 Hz and amplitude of 3 mm, and the control group received an exercise program without vibratory stimulation. Intervention was provided for 4 weeks, 3 sessions per week, and 30 minutes per session. In order to measure lower extremity muscle strength the 30-second chair stand test (CST) was used. The Berg Balance Scale (BBS) was used to measure dynamic balance. Static balance was measured by tracking the path length, velocity, and area of the center of pressure (CoP). The Falls Efficacy Scale (FES) was used to measure the subjects' fear of falling. Results: Both the experimental and control group demonstrated statistically significant increase in muscle strength, dynamic balance, and fall efficacy (p<0.05). Only the experimental group showed significant improvements in static balance before and after the intervention (p<0.05). The experimental group showed significantly greater improvements in CST, BBS, and CoP (path length, velocity) than control group (p<0.05). Conclusions: Whole body vibratory stimulation exercise is shown to be a safe and appropriate physical therapy intervention method to enhance muscle strength, balance, and fall efficacy of super-aged women.

The Effect of Mind Awareness Records on Awareness of Imaginations, Decentering, Parenting stress and Subjective Well-bing: With a Focus on Parents of Adolescents (마음알아차리기 기록이 공상자각, 탈중심화, 양육스트레스 및 주관적 안녕감에 미치는 영향 : 청소년기 자녀를 둔 부모를 중심으로)

  • Jung, Hyun Gi;Sung, Seoung Yun
    • Journal of Family Relations
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    • v.20 no.4
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    • pp.73-103
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    • 2016
  • Objectives: The purpose of this study is to examine the effects of reading mind recording on awareness of imaginations, Method: Decentering, parenting stress and subjective well-being through comparing expressive writing. random assignment was performed on each 13 persons of a recording group (experimental group) and an expressive writing group (comparison group) for reading mind from 26 parents having adolescents. The experimental group conducted the reading of reading mind and the comparison group performed expressive writing twice a week for eight weeks, twenty minutes per time, and responded to four questions on thought arrangement after writing. The researcher participated in the groups once per week and an assignment was suggested once per week. Repeated Measurement Two-way Repeated Measures ANOVA was conducted to confirm the differences according to periods and groups for the data analysis method. In order to examine the changes according to periods, t-test was conducted on the pre- and post-test. Results: The findings are as follows: First, regarding awareness of imaginations and decentering, the reading mind recording group showed a significant result in repeated measurement. Second, the reading mind recording group showed a significant decrease in the pre- and post-t-test about parenting stress. Third, all the reading mind recording group and expressive writing group showed significant results about subjective well-being. Conclusions: This study is significant in that it verified the effectiveness of reading mind recording on awareness of imaginations, decentering and parenting stress, and proved the possibility as an oriental counseling model that considers the characteristics of our culture.

Expansion of K-Content by Global Fandom : Focusing on 'Fansub' Community of Viki (글로벌 팬덤을 통한 한류 콘텐츠의 확대 : Viki의 '팬 자막' 커뮤니티를 중심으로)

  • Kim, Young-Hwan;Jung, Hoe-Kyung
    • Journal of Digital Convergence
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    • v.17 no.11
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    • pp.523-530
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    • 2019
  • This study examines how global fandom for Korean dramas is formed and maintained by examining the reason and purpose of voluntarily making the subtitles of Korean drama through in-depth email interviews with foreign subtitle producers(fan subber) working on a video site called Viki.com. The research focused on Viki's fan community, which has grown into the most influential Korean Wave platform. Collective intelligence expresses in the fan community produces more than professional results and they are acting as consumers, cultural producers, and second creators of K-content. In order to continue the spread of K-content, it needs to pay more attention to the long-term strategy of global fandom combined with the fan community activities of the new media platform and network effects.

The Stress, Self-Efficacy, And Self-Control of University Students Impact on Smartphone Addiction (대학생의 스트레스, 자기효능감, 자기통제력이 스마트폰 중독에 미치는 영향)

  • Ju, Hyeon-Jeong;Jun, Ho-Sun;Park, Mi-Kyung
    • Journal of Digital Convergence
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    • v.17 no.11
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    • pp.395-407
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    • 2019
  • This study attempted to verify the structural model of the effects of stress, self-efficacy, and self-control on smartphone addiction in University students. The subjects of this study were 440 University students in G and P city. Results, First the most influential variables on smartphone addiction were self-control, followed by stress, and two variables explained explanation about smartphone addiction in 34%. Second, self-efficacy had a positive effect on self-control and stress had a negative effect. Both variables had an indirect effect on smartphone addiction through self-control. In groups less than 4 hours and above, there was a partial regulation effect because of differences between groups in the smartphone addiction pathway coefficients of stress and self-efficacy. Therefore, in order to reduce smartphone addiction, it is important to find ways to reduce stress and increase self-control and self-efficacy, and necessary to develop various programs and tailor educational interventions for each individual situation.