• Title/Summary/Keyword: second order effects

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A Study on Law and Standards for Promotion of Aftermarket (애프터시장(판매후시장) 활성화를 위한 국내외 법률 및 표준에 대한 연구)

  • Choi, Sun;Hwang, SangKyu
    • Journal of Environmental Science International
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    • v.22 no.8
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    • pp.1063-1072
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    • 2013
  • To overcome the ecosystem-crisis of resource depletion and climate change, we should maintain and develop a 'Sustainability' of our society. 'After-market' is defined like this : any market where customers who buy one product or service are likely to buy a related follow-on product. This is related to a automotive, electric and electronic, and remanufacturing industry. 'After-market' will be helpful for reuse and recycling of resources aspects, cost and economic efficiency, low-carbon, climate protection, and new industries and job creation effects, To promote 'After-Market', we need to guarantee the quality of products. In this regard, we refer and introduce a new standard, for example, BS8887, PAS141 and ISO20245 etc. In order to promote 'After-Market', first of all, product quality assurance and safety must be demonstrated in the process of reuse. Second, many aspects of a device that protects the rights of consumers to be provided. And third, the related laws and standards should be reviewed. Finally, original manufacturer's awareness for environmental protection and resource conservation and government's institutional support are needed.

Adsorption Characteristics of Cu Ions by Zeolite Na-A Synthesized from Jeju Volcanic Rocks (제주 화산석으로부터 합성한 Na-A 제올라이트에 의한 Cu 이온의 흡착 특성)

  • Ju, Chang-Sik;Lee, Chang-Han;Lee, Min-Gyu
    • Journal of Environmental Science International
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    • v.27 no.5
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    • pp.299-308
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    • 2018
  • The adsorption characteristics of Cu ions were studied using the zeolite Na-A synthesized from Jeju volcanic rocks. The effects of various operating parameters such as initial concentration of Cu ions, contact time, solution pH, and solution temperature were investigated in batch experiments. The adsorption of Cu ions by Na-A zeolite was fitted well by pseudo-second-order kinetics and the Langmuir isotherm model. The maximum adsorption capacity determined using the Langmuir isotherm model was 152.95 mg/g. In addition, the adsorption of Cu ions by zeolite Na-A was primarily controlled by particle diffusion model in comparison with the film diffusion model. As the temperature increased from 303 K to 323 K, ${\Delta}G^o$ decreased from -2.22 kJ/mol to -3.41 kJ/mol, indicating that the adsorption of Cu ions by Na-A zeolite is spontaneous process.

Removal of 2,4-Dinitrophenol from an Aqueous Solution by Wood-Based Activated Carbon (목질계 활성탄을 이용한 수중의 2,4-Dinitrophenol 흡착 제거)

  • Ju, Chang-Sik;Lee, Min-Gyu
    • Journal of Environmental Science International
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    • v.26 no.5
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    • pp.609-619
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    • 2017
  • The removal characteristics of 2,4-dinitrophenol (2,4-DNP) from an aqueous solution by commercial Wood-based Activated Carbon (WAC) have been studied. The effects of various experimental parameters were investigated using a batch adsorption technique. The adsorption capacity of 2,4-DNP by WAC increased with a decrease in the dosage and particle size of WAC, temperature and the initial pH of the solution, and increased with an increase in the initial concentration of the solution. The adsorption equilibrium data were best described by the Redlich-Peterson isotherm model. The maximum adsorption capacities of 2,4-DNP by WAC were 573.07 mg/g at 293 K, 500.00 mg/g at 313 K, and 476.19 mg/g at 333 K, decreasing with increasing temperature. The kinetic data were well fitted to the pseudo-second-order model, and the results of the intra-particle diffusion model suggested that the adsorption process was mainly controlled by particle diffusion. The thermodynamic analysis indicated that the adsorption of 2,4-DNP by WAC was an endothermic and spontaneous process.

An Exploratory Study on the Selection Attributes of Food Courts through the Conjoint Analysis (컨조인트 분석을 통한 푸드코트 선택 속성에 관한 탐색적 연구)

  • Jung, Young-Woo;Lee, Eun-Yong
    • Culinary science and hospitality research
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    • v.14 no.4
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    • pp.106-118
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    • 2008
  • Even though the number of food courts increased in recent years, there were few studies about them. Considering the effects of a food court on the sales of a mall or other shopping spots, it was necessary to analyze what kind of attribute attracts customers. For this research, conjoint analysis was used to test which attribute was the most decisive factor, and the results of this study were as follows. First, price was the first factor that customers attached great importance to. Next were time required from order to eat and menu diversity. Second, cluster analysis used by the individual value of utilities derived through the conjoint analysis showed two clusters. Third, the most preferred food court form gained 35.4% potential market share from the simulation. The information gained from this analysis provided an important starting point for marketing and determined what kind of attribution was considered in being part of the malls or buildings. Also, it could be made full use of creating and executing the most effective marketing strategies.

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A 0.25-$\mu\textrm{m}$ CMOS 1.6Gbps/pin 4-Level Transceiver Using Stub Series Terminated Logic Interface for High Bandwidth

  • Kim, Jin-Hyun;Kim, Woo-Seop;Kim, Suki
    • Proceedings of the IEEK Conference
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    • 2002.06b
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    • pp.165-168
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    • 2002
  • As the demand for higher data-rate chip-to-chip communication such as memory-to-controller, processor-to-processor increases, low cost high-speed serial links\ulcorner become more attractive. This paper describes a 0.25-fm CMOS 1.6Gbps/pin 4-level transceiver using Stub Series Terminated Logic for high Bandwidth. For multi-gigabit/second application, the data rate is limited by Inter-Symbol Interference (ISI) caused by channel low pass effects, process-limited on-chip clock frequency, and serial link distance. The proposed transceiver uses multi-level signaling (4-level Pulse Amplitude Modulation) using push-pull type, double data rate and flash sampling. To reduce Process-Voltage-Temperature Variation and ISI including data dependency skew, the proposed high-speed calibration circuits with voltage swing controller, data linearity controller and slew rate controller maintains desirable output waveform and makes less sensitive output. In order to detect successfully the transmitted 1.6Gbps/pin 4-level data, the receiver is designed as simultaneous type with a kick - back noise-isolated reference voltage line structure and a 3-stage Gate-Isolated sense amplifier. The transceiver, which was fabricated using a 0.25 fm CMOS process, performs data rate of 1.6 ~ 2.0 Gbps/pin with a 400MHB internal clock, Stub Series Terminated Logic ever in 2.25 ~ 2.75V supply voltage. and occupied 500 * 6001m of area.

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Effects on learners' learning self-efficacy and English accomplishments by two types of level-based collaborative groupworks (수준별 소집단 협력학습 유형이 학습자의 학업적 자기효능감과 영어학업성취도에 미치는 영향)

  • Lee, Nam-Sook;Im, Byung-Bin
    • English Language & Literature Teaching
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    • v.12 no.4
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    • pp.211-234
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    • 2006
  • The purpose of the present study was to investigate how two types of cooperative groupworks will affect learners' academic self-efficacy and English achievement in the first graders of Middle school. Experimental class A was done by similar-level groupwork, experimental class B by differential-level groupwork, and controlled class C by whole classwork. In order to accomplish the goals of the study, questionnaires on learners' academic self-efficacy were examined before and after the experiment. Also English achievement tests were done during the experiment. The analytic results of the questionnaires and English achievement tests were like the following conclusions: First, two types of cooperative groupworks were more effective on improving learners' academic self-efficacy than the whole classwork. Second, two types of cooperative groupworks were more effective on improving two levels' (higher and medium) academic self-efficacy. Third, among three types of classworks, differential-level groupwork was the most effective on improving learners' English achievement. Fourth, in case of medium-level learners, differential-level groupwork was more effective on improving their English achievement than similar-level groupwork.

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Informational Social Influence on Clothing Conformity (정보적 영향에 의한 의복동조성 연구)

  • 정미실
    • Journal of the Korean Home Economics Association
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    • v.29 no.3
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    • pp.1-10
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    • 1991
  • The purpose of the present study was to identify the effects of communicator, type of clothing and subject's age on informational influence in clothing conformity. The sample consisted of 205 subjects assigned to two groups (female college students in their early twenties and housewives in their late thirties living in kyongju). In this study the research design consisted of a 3(communicator)×2(subject's age)×2(type of clothing) factorial design. The stimuli consisted of 10 color photographs (6 one-piece dresses and 4 jeans in current fashion) In the first step, subjects were asked to arrange stimuli in the order of greatest fashionability. In the second step, subjects were exposed to experimental manipulation which consisted of slides of various clothing styles and an essay concerning a forecast on fashion trends. The communicator in the essay was described as a designer, a college student, or a housewife. In the third step, in addition to other questions subjects were asked to indicated their degree of agreement with the essay. The data were analyzed by ANOVA, X2 and t-test. The results were: 1. Informational influence on clothing conformity varied by communicator, type of clothing, and subject's age. Subjects were most conforming when the communicator was described as a designer and when the clothing style was a one-piece dress. 2. Informational influence results revealed that housewives were more conforming than the female college students in the jean style.

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Effect of Social Media Use Motivation on Satisfaction and Revisit Intention : Focused on Rural Tourism Visitors (소셜미디어 이용동기가 만족과 재방문의도에 미치는 영향 : 농촌체험마을 이용자를 중심으로)

  • Mun, Young-Ju;Jung, Chul-Ho
    • The Journal of the Korea Contents Association
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    • v.11 no.9
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    • pp.202-211
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    • 2011
  • This study was to explore the effect of rural tourism social media use motivation on satisfaction and revisit intention. In order to carry out the empirical study 397 survey questionnaires were collected in rural tourism social media users, PASW18 and Lisrel 8.54 statistics package were utilized for analysis of SEM The study result were as follows: first, social media use motivation had a positive influence upon satisfaction. second, social media use satisfaction had a positive influence upon revisit intention. The study suggested that need to gather extensive opinions from visitors to created and manage rural tourism village in a rational manner, and intensive research effects should be directed into the vitalizations of rural tourism villages.

A Study on Metal Expressed in Contemporary Fashion -Focusing on Women's Fashion in 1990s- (현대패션에 나타난 금속에 관한연구 -1990년대 여성복을 중심으로-)

  • 금기숙
    • Journal of the Korean Society of Costume
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    • v.45
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    • pp.161-178
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    • 1999
  • In contemporary fashion metal have used which is as the material with a sufficient potentiality of expression which is displayed by an unique characteristic involved only in metal. In this paper metal expressed in contemporary fashion is researched. The first thing the formative characteristic of metal is researched under the consideration of type technique and color of metal used in contemporary fashion. Metals such as gold silver bronze aluminum thin lead and iron are usually used in fashion and those metals are used in various types such a thread fabric board leaf a and cable. Those types of metal as above are applied to the clothing by the techniques of weaving embroidering metal leaf printing or moulding which gives the formative characteristic to the clothing. In color metal has an effect on the colors of surroundings by its smooth and unique luster and its effect of reflection and produces the visual formative characteristic through the effects of contrast. The esthetic will of metal expressed in modern fashion is researched in this study under the facts studied as above. first metal expresses the future oriented esthetic Second metal has the characteristic of attracting the attention Third metal is used as valid techniques to express the artistic formation for clothing escaping from the idea that the clothing is only for wearing. Finally metal is used as an anti-cultural tool of fighting against the existing order or spirit.

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Geometric Non-linear Analysis of the Plane Frame Structures including Shear Deformation Effect (전단변형(剪斷變形)을 고려(考慮)한 평면(平面)뼈대 구조물(構造物)의 기하적(幾何的)인 비선형(非線形) 해석(解析))

  • Kim, Moon Young;Chang, Sung Pil
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.10 no.1
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    • pp.27-36
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    • 1990
  • Two beam/column elements in order to analyze the geometric nonlinear plane framed structures including the effects of transverse shear deformation and bending stretching coupling are developed. In the case of the first element (finite segment method), tangent stiffness matrix are derived by directly integrating the equilibrium equations whereas in the case of the second element (finite element method) elastic and geometric stiffness matrices are calculated by using the hermitian polynomials including shear deformation effect as the shape function. Both elements possess the usual six degree of freedoms. Numerical results are presented for the selected test problems which demonstrate that both elements represent reliable and highly accurate tools.

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