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A Study on the Removal Efficiency of Heavy Metals in Daenam Mine Agricultural Soil Using Heavy metal Properties by Physical separation (대남광산 농경지 토양 내 중금속 특성에 따른 물리적 선별 처리효율에 관한 연구)

  • ParK, Chan Oh;Hong, Dong-Ho;Lee, Jai-Young;Lee, Young Jae;Lee, Jin-Soo
    • Journal of Soil and Groundwater Environment
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    • v.18 no.5
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    • pp.46-55
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    • 2013
  • The main objective was to evaluate the efficiencies of different separation techniques, such as gravity separation, magnetic separation, and aerial separation. Zinc and cadmium removal efficiencies by gravity separation and magnetic separation were 28.3~29.3% and 19.1%, respectively, and were higher than the efficiency obtained by aerial separation. Results showed that the combination of gravity separation and magnetic separation in series which was to maximize the removal efficiencies gave removal efficiency of 21.5~38.7% for zinc and 22.1~23.4% for cadmium. The mass of soil meeting the regulation standards for zinc and cadmium after retrieval from the combined separation process accounted for approximately 80% of the treated soil that would be reusable without the pre-treatment procedure as the neutralization process using in the soil washing method. Physical separation techniques utilizing heavy metal properties are the alternative method to remediate heavy-metal contaminated soils in environmental and economic aspects.

The Effects of Working Mothers' Separation Anxiety, Job Satisfaction, and Overprotective Parenting Behavior on Preschoolers' Separation Anxiety (취업모의 분리불안, 직업만족도 및 과보호적 양육행동이 유아의 분리불안에 미치는 영향)

  • Ryoo, Jung-min;Shin, Nana
    • Korean Journal of Childcare and Education
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    • v.14 no.1
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    • pp.1-20
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    • 2018
  • Objective: The purpose of this study was to examine the direct and indirect effects (through working mothers' overprotective parenting behavior) of working mothers' separation anxiety and job satisfaction on preschoolers' separation anxiety. Methods: A total of 251 working mothers with preschool-aged children participated in this study. Mothers completed a questionnaire concerning their separation anxiety, job satisfaction, overprotective parenting behavior, and preschoolers' separation anxiety. Data were analyzed using t-test, one-way ANOVAs, partial correlations and path analysis. Results: In terms of direct effects, working mothers' separation anxiety had a direct effect on preschoolers' separation anxiety. However, job satisfaction did not have a direct effect on preschoolers' separation anxiety. With respect to indirect effects, working mothers' separation anxiety indirectly influenced preschoolers' separation anxiety through their overprotective parenting behavior. However, mothers' job satisfaction did not have an indirect effect on preschoolers' separation anxiety. Conclusion/Implications: Findings from this study emphasize the importance of reducing mothers' separation anxiety in order to prevent preschoolers' separation anxiety.

Maternal parenting behaviors, child's stranger anxiety, separation anxiety, and maternal separation anxiety (자녀 양육행동 , 아동의 낯가림 경험 및 분리불안과 어머니의 분리불안)

  • Ahn, Jee-Young;Doh, Hyun-Sim
    • Journal of the Korean Home Economics Association
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    • v.36 no.8
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    • pp.13-20
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    • 1998
  • The purpose of this study was to examine the relations of matemal parenting behaviors, child's stranger anxiety, and separation anxiety to matemal separation anxiety. A total of 288 middle class mothers having children aged from 36- to 59-month- olds answered to a questionnaire based on Maternal Separation Anxiety Scale (Hock, 1989). They also answered the questions about maternal parenting behaviors, child's stranger anxiety, and separation anxiety. The main results were as follows : 1. There were no significant differences in maternal separation anxiety as a function of demographic variables. 2. Maternal parenting behaviors such as physical contact and discipline involvement were significantly related to maternal separation anxiety. And child's stranger anxiety and separation anxiety were also significantly related to matemal separation anxiety. 3. Maternal separation anxiety was accounted for 15% of the variance by maternal physical contact, discipline involvement, and chlid's stranger anxiety and separation anxiety.

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Flow Field Change before Onset of Flow Separation

  • Hasegawa, Hiroaki;Sugawara, Takeru
    • International Journal of Fluid Machinery and Systems
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    • v.2 no.3
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    • pp.215-222
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    • 2009
  • Jets issuing through small holes in a wall into a freestream has proven effective in the control of flow separation. This technique is known as the vortex generator jet (VGJs) method. If a precursor signal of separation is found, the separation control system using VGJs can be operated just before the onset of separation and the flow field with no separation is always attained. In this study, we measured the flow field and the wall static pressure in a two-dimensional diffuser to find a precursor signal of flow separation. The streamwise velocity measurements were carried out in the separated shear layer and spectral analysis was applied to the velocity fluctuations at some angles with respect to the diffuser. The pattern of peaks in the spectral analysis changes as the divergence angle increases over the angle of which the whole separation occurs. This change in the spectral pattern is related to the enhancement of the growth of shear layer vortices and appears just before the onset of separation. Therefore, the growth of shear layer vortices can be regarded as a precursor signal to flow separation.

The Characteristics of Separation Color Coordination In Current Women's Fashion collections of Paris, Milan, N.Y, London from 2004 SS - 2008 A W - centering on the types of color scheme, color harmony, separation color - (최신 여성 패션에 나타난 세퍼레이션 색채 코디네이션의 특성)

  • Kwon, Hae-Sook
    • Journal of Fashion Business
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    • v.12 no.5
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    • pp.94-110
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    • 2008
  • The main objective of this research was to understand the characteristics of separation color coordination of contemporary female fashion through the analysis of 'pre-a-porter Collections' of four collections (i. e. cities) - Paris, Milan, New York, London - from the periods of 2004 S/S to 2008/9 A/W. The data collection of 265 was done by reviewing 'pre-a-porter Collections' magazine and total 265 observations were made. Statistical analysis of frequency and also qualitative interpretation of separation color coordination characteristics were completed. The main findings were; (1) In separation color coordination of contemporary women's fashion collections, there were three main types of color scheme which were classified into seven detailed categories of color combination. First was the achromatic color & one chromatic separation color scheme which was classified into four categories of - black & white, black & grey, white & grey, and grey & grey - color combination. Second was the chromatic colors & one achromatic separation color scheme which classified into two categories of achromatic & chromatic color & one achromatic separation color combination, and chromatic colors & one achromatic separation color combination. Third was chromatic colors and one chromatic separation color combination. (2) The achromatic colors and one chromatic separation color scheme showed two phases of reinforcing the strong and modern image, or softening the hard and dull image of achromatic color combination. In color schemes which used more than two chromatic colors, the separation color frequently converted the tedious and monotonous fashion image, which caused by identical or similarity in color or tone harmony, into more attractive and interesting. (3) In conclusion, through the various use and coordination of various color schemes, color harmony and separation colors, the separation color coordination in contemporary female fashion has been suggested the effective way of color combination which can lead the visual pleasure and the vitality along with the unity and the harmony. This characteristics can create various images and visual diversity for fashion. The types and the use of color scheme and separation color showed different trends in four collections.

A Cohesive Surface Separation Potential

  • Lee, Youngseog;Kim, Kwang-Soo
    • Journal of Mechanical Science and Technology
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    • v.16 no.11
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    • pp.1435-1439
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    • 2002
  • This paper presents a form of the cohesive surface separation potential, which can produce potential curves by varying a single dimensionless parameter. Results show that a partial modification of Xu and Needleman's (1994) cohesive surface separation potential makes it possible to present the other potential corves as a special case as long as the normal separation is concerned. The proposed potential may describe interfacial debonding-crack initiation and growth-character of materials and, through numerical simulation, provide an insight for the effect of different cohesive surface separation potentials on the interfacial debonding.

Enantioselective Membranes Based on Chitosan for The Separation of D- And L-Tryptophan

  • Jonggeon Jegal;Kim, Jang-Hoon;Kim, Jee-Hye;Lee, Kew-Ho;Lee, Yongtaek
    • Korean Membrane Journal
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    • v.5 no.1
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    • pp.25-30
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    • 2003
  • Chitosan membranes crosslinked with glutaraldehayde that contained chiral environment were prepared. The chitosan membranes were characterized using FTIR and swelling index measurements. Their swelling index in water ranged from 100 to 70%, depending on the crosslinking time. The separation of D- and L-isomers of tryptophan was achieved through a pressure driven membrane separation process, using the self-supporting crosslinked chitosan membranes. The chiral separation performance of the membranes depended strongly on the swelling index of the membranes and the separation conditions such as concentration of feed solutions and different operating pressures. Especially when a chitosan membrane with a swelling index of 70% was used, almost complete optical resolution of D- and L-tryptophan was obtained ; enantiomeric excess (ee %) of 97.92% and flux of 2.26 g/㎡$.$h.

유기물 분리용 투과증발막

  • 박현채
    • Proceedings of the Membrane Society of Korea Conference
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    • pp.69-90
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    • 1996
  • In the chemical industry, in the pharmaceutical industry, and in a number of other industries separation processes are necessary to separate and purify products and raw materials [1,2]. Separation processes are also widely used in other applications such as in recycling valuable materials from waste streams. Unit operations for separation processes can be classified in phase separation techniques and component separation techniques based on the nature of the feed mixtures to be separated. The former techniques are used for the separation of heterogeneous mixtures, in which the feed is already present in two or more separated phases on a micro-scale. The latter are suitable for the separation of homogeneous mixtures such as gaseous mixtures and mixtures of completely miscible liquids. tn these cases the separation into individual components is generally achieved by utilizing the differences in physico-chemical properties of components, and is much more difficult compared to phase separation techniques. Separation processes such as distillation, evaporation, liquid-liquid extraction, and crystallization belong to this class.

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Consumer Evaluation on Visual Sensibility of Stripe Pattern Shirts - Focusing on Separation Coloration - (줄무늬 셔츠의 시각적 감성에 대한 소비자 평가 - 세퍼레이션 배색을 중심으로 -)

  • Choi, Soo-Kyoung
    • Journal of the Korea Fashion and Costume Design Association
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    • v.16 no.2
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    • pp.71-80
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    • 2014
  • The purpose of this study was to investigate consumer evaluation on visual sensibility of stripe pattern shirts for separation coloration. The experimental materials developed for this study were a set of clothing stimuli and response scales. The clothing stimuli were 27 color pictures, in which separation color(white: W, gray: G, black: B), separation width(small: S, medium: M, large: L), and combination color(magenta and yellow: MY, magenta and cyan: MC, yellow and cyan: YC) were manipulated. The subjects of this research were female in their 20s to 30s living in Seoul, Gwangju, Daegu, Busan, and Changwon. The investigation was carried out at December 2013. The data were analyzed by using SPSS program. Analysis methods were factor analysis, ANOVA, and Duncan-test. Results of this study were as follow.; The factors of visual sensibility according to separation color, separation width, and combination color consisted of four dimensions of attractiveness, appeal, individuality freshness, and grace. Separation color showed an independent effect on appeal and individuality freshness. Combination color showed an independent effect on individuality freshness. Interaction effects of separation color and separation width on appeal were found. Interaction effects of separation color and combination color on individuality freshness and grace were found. The study results are highly expected to be used as useful sources in a fashion product.

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Dry Separation of PVC Film from Plastic Film Mixture by Using Air Table

  • Song, Young-Jun;Hiroki Yotsumoto;Lee, Gye-Seung
    • Journal of the Korean Institute of Resources Recycling
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    • v.11 no.1
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    • pp.37-42
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    • 2002
  • This study was conducted in order to remove Poly vinyl chloride(PVC) from the waste plastic film mixture. The fittings of Air Table was modified to increase the separation efficiency of PVC and PE(poly ethylene). PE and PVC was successfully separated from PVC-PE film mixture with the yield of PE 90% or more and with his grade of 99% or more, using the improved Air Table. The details of the separation condition and results will be discussed in this paper. Dry separation, Waste plastic film, PVC, Air Table. The details of the separation condition and results will be discussed in this paper.