• Title/Summary/Keyword: separations

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Factors Influencing Limerence in Dating Relationships among Female College Students (여대생을 대상으로 한 이성 교제의 집착 행동에 영향을 주는 요인)

  • Kim, Oksoo;Jeon, Hae Ok
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.2
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    • pp.304-314
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    • 2020
  • This cross-sectional descriptive study investigated the influence of romantic relationships' characteristics, self-esteem and sexual autonomy on limerence in dating relationships among female college students who had or were currently engaged in a dating relationship. The data was collected through self-reported structured questionnaires from 167 female Korean college students using convenient sampling methods from November 25, 2012 to December 20, 2012. The data was analyzed using t-tests, one-way analyses of variance, Scheffe's test, Pearson's correlation coefficients, and multiple linear regression analysis with the IBM SPSS 23.0 program. The results showed that a significant difference was found in limerence according to the frequency of experiencing romantic breakup (F=4.16, p=.003), and limerence in dating relationships was negatively correlated with self-esteem (r=-.31, p<.001) and sexual autonomy (r=-.21, p=.006). Self-esteem and the frequency of romantic breakups explained 20% of limerence in dating relationships among the participants (F=8.03, p<.001). Therefore, as a strategy to solve the problems related to limerence during the period of dating, cognitive and educational interventions are needed to strengthen the self-esteem and sexual autonomy of college students who have had a high number of separations. In addition, early screening of college students with risk factors for limerence and providing problem-solving based counseling will help improve their psychological health.

Observation of behavior of the Ahlat Gravestones (TURKEY) at seismic risk and their recognition by QR code

  • Isik, Ercan;Antep, Baris;Buyuksarac, Aydin;Isik, Mehmet Fatih
    • Structural Engineering and Mechanics
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    • v.72 no.5
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    • pp.643-652
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    • 2019
  • Protection of cultural heritage and carrying it to the future are at the top of the significant topics of research and implementation in engineering in the 21st century. There are several historical structures in the district of Ahlat located in the east of Turkey on the Lake Van Basin that has harbored many civilizations. Some of such works are the gravestones that are found in the Ahlat Seljuk Cemetery, which is the oldest and largest cemetery in the district. This study firstly provides information about the Ahlat Seljuk Cemetery and the gravestones found in it. Observation-based structural analyses were carried out on these gravestones that are found in this area that are known to have belonged to different civilizations based on their physical and constructional characteristics. These stones were built out of Ahlat stone as single pieces. Information is provided on the damages that have occurred on the gravestones in time and their causes. In general, losses of mass, abrasions, separations, collapses and calcifications due to natural conditions, as well as vegetative formations, were observed in the gravestones. To provide an example of other gravestones within the context of the study, the gravestone that is known to belong to the person named Nureddin Ebu Hasan was selected. As a result of the modeling that was carried out for this gravestone by using the finite elements method, modal analyses were carried out. With these analyses, for the gravestone, period, effective mass participation rates and stress values were calculated. The stress values that were obtained in this study were compared to the material safety stress values that were obtained in previous studies. Additionally, QR code application was created for the gravestone that was selected as an example in the study, and information on this gravestone was transferred to an electronic environment. The QR code application includes different language options, visuals of the gravestone and information on the gravestone. The QR application was also supported with a video of the cemetery where the gravestone is located. With this application, access to information about gravestones will be possible by using tablets and smartphones. With a QR code to be created for each gravestone, these gravestones will obtain identity cards.

The Anion Exchange Chromatographic Studies on the Polymerization Equilibria of Molybdate and Tungstate and the Production of APT (음이온 교환크로마토그래피에 의한 몰리브덴산과 텅스텐산의 중합, 평형 및 APT 제조에 관한 연구)

  • Cha Ki Won;Park Kee Chae
    • Journal of the Korean Chemical Society
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    • v.19 no.4
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    • pp.225-232
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    • 1975
  • The elution behaviour of molybdate and tungstate through anion exchange column has been studied at the various pH. A discussion is made to evaluate the equilibrium constants of the polymerization of these acids comparing with the behaviour of chromate ion and dichromate ion. The eqailibrium constants found at $20^{\circ}$ are $K = 4{\times}10^{53} for 7MoO_4^{2-} + 8H^+ {\longleftrightarrow} Mo7O_{24}^{6- }+ 4H_2O$$ K = 3{\times}10^{54} for 6WO_4^{2-} + 7H^+ {\longleftrightarrow} HW6O_{21}^{5-} + 7H_2O$ referring to this results the conditions of separation of tungstate and molybdate are obtained. iThe quantitative separations of carbonate, molybdate and tungstate from the pregnant solution have been established by anion exchange chromatography, using the $22 cm{\times}44.27 cm^2$ column of Rexyn 201. The optimum eluents for the quantitative separation of those ions are as follows; 0.2M solution of sodium chloride at pH 8 for carbonate, the mixture of 0.5 M ammonium chloride and 0.05 M sodium sulfate at pH 5 for molybdate and 0.5 M solution of ammonium chloride at pH 10 for tungstate. Tungstate is directly recovered from the pregnant solution as a form of ammonium paratungstate, by eluting with ammonium chloride solution.

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Separations and Feature Extractions for Image Signals Using Independent Component Analysis Based on Neural Networks of Efficient Learning Rule (효율적인 학습규칙의 신경망 기반 독립성분분석을 이용한 영상신호의 분리 및 특징추출)

  • Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.13 no.2
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    • pp.200-208
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    • 2003
  • This paper proposes a separation and feature extraction of image signals using the independent component analysis(ICA) based on neural networks of efficient learning rule. The proposed learning rule is a hybrid fixed-point(FP) algorithm based on secant method and momentum. Secant method is applied to improve the performance by simplifying the 1st-order derivative computation for optimizing the objective function, which is to minimize the mutual informations of the independent components. The momentum is applied for high-speed convergence by restraining the oscillation in the process of converging to the optimal solution. The proposed algorithm has been applied to the composite images generated by random mixing matrix from the 10 images of $512\times512$-pixel. The simulation results show that the proposed algorithm has better performances of the separation speed and rate than those using the FP algorithm based on Newton and secant method. The proposed algorithm has been also applied to extract the features using a 3 set of 10,000 image patches from the 10 fingerprints of $256\times256$-pixel and the front and the rear paper money of $480\times225$-pixel, respectively, The simulation results show that the proposed algorithm has also better extraction speed than those using the another methods. Especially, the 160 basis vectors(features) of $16\times16$-pixel show the local features which have the characteristics of spatial frequency and oriented edges in the images.

Principles of Simulated Moving Bed Reactor(SMBR) (Simulated Moving Bed Reactor(SMBR)의 원리)

  • Song, Jae-Ryong;Kim, Jin-Il;Koo, Yoon-Mo
    • Korean Chemical Engineering Research
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    • v.49 no.2
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    • pp.129-136
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    • 2011
  • Simulated Moving Bed(SMB) process consists of multiple chromatographic columns, which are usually partitioned into four zones. Such a process characteristic allows a continuous binary separations those are impracticable in conventional batch chromatographic processes. Compared with batch chromatography, SMB has advantages of continuity, high purity and productivity. Various researches have been reported for the integration of reaction and recovery during process operation on the purpose of economics and effectiveness. Simulated Moving Bed Reactor(SMBR) is introduced to combine SMB as a continuous separation process and reactor. Several cases of SMBR have been reported for diverse reactions with catalytic, enzymatic and chemical reaction on ion exchange resin as main streams. With an early type of fixed bed using catalyst, SMBR has been developed as SMB using fluidized enzyme, SMB with immobilized enzyme and SMB with discrete reaction region. For simple modeling and optimization of SMBR, a method considering convection only is possible. A complex method considering axial dispersion and mass transfer resistance is needed to explain the real behavior of solutes in SMBR. By combining reaction and separation, SMBR has benefits of lower installation cost by minimizing equipment use, higher purity and yield by avoiding the equilibrium restriction in case of reversible reaction.

A Derivation of the Representative Unit Hydrograph from Multiperiod Complex Storm by Linear Programming (선형계획법(線型計劃法)에 의한 대표단위도(代表單位圖) 유도(誘導))

  • Kwon, Oh Hun;Ryu, Tae Sang;Yoo, Ju Hwan
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.2
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    • pp.173-182
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    • 1993
  • This paper presents an algorithm to derive the representative unit hydrograph for the real environment of a watershed. For a given watershed, the conventional methods give several different unit hydrographs by storm events. In this study the LP model is somewhat modified based on the previous study by Mays et also as follows: the objective function is designed to minimize the sum of weighted residuals. An additional constraint of moving average is added to prevent the unit hydrograph from the occurence of oscillation which was not active in Mays's paper. Configuration of rainfall matrix was improved to reduce its dimension in accordance with Diskin's review point. In spite of the superiority of LP approach in terms of representativeness, all the methods were very sensitive to the validity of baseflow separation and rainfall-loss. Several methods of the separations for rainfall excesses and direct runoffs were applied and no preferred methods were identified. This is the matter of judgement considering catchment and rainfall characteristics. This algorithm was applied to a real watershed of the Wi stream in the Nak-dong river. Compared with the IHP results by conventional methods, this optimized representative unit hydrograph demonstrated relatively smaller and shorter values in terms of the peak discharge and the basin lag respectively, and the oscillation of its falling limb successfully eliminated owing to the additional constraints of moving averages.

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Dose Distribution of 3-Channel Ovoid Applicator (3-Channel Vaginal Ovoids의 선량분포 특성)

  • Kim Chang Hee;Yun Sang Mo;Kim Sung Kyu;Shin Sei One
    • Progress in Medical Physics
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    • v.15 no.3
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    • pp.134-139
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    • 2004
  • This study was aimed to develop a new ovoid applicator for vaginal high-dose rate intracavitary radiation therapy, evaluate uniformity of dose distribution, and assess clinical applicability. The authors evaluated dose uniformity of vaginal mucosa according to 5-different ovoid-separation using 2-channel and modified 3-channel ovoid applicator. There were no significant differences in the dose distribution along the vaginal mucosa with 2 and 2.5 cm separations, but there were between the 2-channel and 3-channel ovoid applicator with a separation of 3 cm or more. Although a low dose area was shown between two ovoid applicators with the 2-channel ovoid applicator, the dose distribution along the vaginal mucosa with the 3-channel ovoid applicator was very uniform.

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Effect of the Duck Skin on Quality Characteristics of Duck Hams

  • Kim, Dong-Hyun;Kim, Tae-Kyung;Kim, Young-Boong;Sung, Jung-Min;Jang, YoungJin;Shim, Jae-Yun;Han, Sung-Gu;Choi, Yun-Sang
    • Food Science of Animal Resources
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    • v.37 no.3
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    • pp.360-367
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    • 2017
  • This study was conducted to investigate the effect of duck skin on cooking loss, emulsion stability, pH, color, protein solubility, texture profile analysis (TPA), apparent viscosity, and sensory characteristics of press type duck ham with different ratio of duck breast meat and duck skin. Five duck ham formulations were produced with the following compositions: T1 (duck breast 70% + duck skin 30%), T2 (duck breast 60% + duck skin 40%), T3 (duck breast 50% + duck skin 50%), T4 (duck breast 40% + duck skin 60%), and T5 (duck breast 30% + duck skin 70%). The cooking loss and fat separation were lower in T1, and the total expressible fluid separations were lower in T1 and T2 than others. The pH ranged from 6.48 to 6.59, with the highest values in T4 and T5. T5 had the highest CIE $L^*$-value, and T1 and T2 had the highest CIE $a^*$-values; however, CIE $b^*$-values did not differ significantly between the duck ham samples. The protein solubility and TPA (hardness, springiness, cohesiveness, gumminess, and chewiness) were the highest in T1. T1 and T2 had higher scores for color, tenderness, and overall acceptability. T1, T2, and T3 showed significantly higher values, but there were no significant differences for flavor and juiciness. Regarding apparent viscosity properties, T1 and T2 had higher viscosity values than the other formulations. In conclusion, the T1 (duck breast 70% + duck skin 30%) and T2 (duck breast 60% + duck skin 40%) duck hams show the highest quality characteristics.

Purification and characterization of antifungal compounds produced by Bacillus subtilis KS1 (Bacillus subtilis KS1이 생산하는 항진균물질의 정제 및 특성)

  • Ryoo, Sung-Woo;Maeng, Hack-Young;Maeng, Pil-Jae
    • The Korean Journal of Mycology
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    • v.24 no.4 s.79
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    • pp.293-304
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    • 1996
  • A bacterial strain, KSl, possessing strong antifungal activity was isolated from soil samples of ginseng fields and identified as Bacillus subtilis. In greenhouse test, the culture filtrate of B. subtilis KS1 showed strong protective effect against several fungal diseases of agricultural plants such as cucumber gray mold and wheat leaf rust. In addition, the crude butanol fraction of the culture filtrate exhibited antagonistic effect against several fungi including plant or human pathogens, such as Botrytis maydis, Chytridium lagenarium and Candida albicans. The antifungal compound, SW1, produced by B. subtilis KS1 was purified through consecutive chromatographic separations on a pep-RPC column and a ${\mu}$ Bondapak $C_{18}$ reverse phase column. Temperature and pH showed little effect on the stability of the compound in the ranges $-20-121^{\circ}C$ and pH 4.0-10.0, respectively. The composition and structural characteristics of SW1 were analysed by HPLC and by $^1H-,\;^1H-^1H-COSY$, NOESY, COSY-NOESY and HOHAHA NMR spectroscopy, respectively, which revealed that the compound belongs to iturin A, a typical cyclic antifungal compound produced by B. subtilis. In contrast to the previously reported iturin A compounds which have one or no $-CH_3$ side chain in the hydrophobic hydrocarbon chain of ${\beta}-amino$ acids, SW1 was shown to have a ${\beta}-amino$ acid containing 12-carbon skeleton with two $-CH_3$ side chains.

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Modeling Study on a Circulatory Hollow-Fiber Membrane Absorber for $CO_{2}$ Separation (이산화탄소 분리를 위한 순환식 중공사 막흡수기에 관한 모델링 연구)

  • Chun, Myung-Suk;Lee, Kew-Ho
    • Membrane Journal
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    • v.5 no.1
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    • pp.35-43
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    • 1995
  • For several years lots of attempts have been made to establish the liquid membrane-based techniques for separations of gas mixtures especially containing carbon dioxide. A more effective system to separate $CO_{2}$ from flue gases, a circulatory hollow-fiber membrane absorber(HFMA) consisting of absorption and desorption modules with vacuum mode, has been considered in this study. Gas-liquid mass transfer has been modeled on a membrane module with non-wetted hollow-fibers in the laminar flow regime. The influence of an absorbent flow rate on the separation performance of the circulatory HFMA can be predicted quantitatively by obtaining the $CO_{2}$ concentration profile in a tube side. The system of $CO_{2}/N_{2}$ binary gas mixture has been studied using pure water as an(inert) absorbent. As the absorbent flow rate is increased, the permeation flux(i.e., defined as permeation rate/membrane contact area) also increases. The enhanced selectivity compared to the previous results, on the other hand, shows the decreasing behavior. It has been found obviously that the permeation flux depends on the variations of pressure in gas phase of desorption module. From an accurate comparison with the results of conventional flat sheet membrane module, the advantageous permeability of this circulatory HFMA can be clearly ascertained as expected. Our efforts to the theoretical model will provide the basic analysis on the circulatory HFMA technique for a better design and process.

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