• Journal of IKEEE
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• v.27 no.1
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• pp.109-115
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• 2023

In this paper, we design and implement an Ultra-Wide Band (UWB, 3.1~10.6 GHz) antenna with 5G mobile communication (3.42~3.70 GHz) and Wireless Local Area Network (WLAN, 5.15~5.825 GHz) bands rejection characteristics. The proposed antenna consists of a planar radiation patch with two slots. The upper slot contributes to reject 5G mobile communication band and the lower slot contributes to reject WLAN band. The Voltage Standing Wave Ratio (VSWR) values of the proposed antenna show good performances in whole UWB band except for rejection bands based on VSWR 2.0. The proposed UWB antenna was simulated using High Frequency Struture Simulator (HFSS) by Ansoft. The simulated antenna showed dual rejection bands of 3.31~3.92 GHz and 5.04~5.90 GHz in UWB band, and measured antenna showed dual rejection bands of 3.35~3.97 GHz and 5.06~5.97 GHz. The largest VSWR values measured at each rejection band are 13.60 at 3.64 GHz and 10.25 at 5.52 GHz. The measured maximum gain is 5.31 dBi at 10.00 GHz. The lowest gains for the measured antenna at rejection bands are -8.73 dBi at 3.70 GHz and -4.36 dBi at 5.56 GHz.

• Korean Journal of Child Studies
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• v.37 no.4
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• pp.31-46
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• 2016

Objective: This study examined the influences of maternal and paternal psychological control and children's rejection sensitivity on relational aggression in elementary school students, and investigated whether children's rejection sensitivity mediated the relation of parental psychological control and relational aggression. Methods: The participants of this study were 596 fifth to sixth graders from seven elementary schools located in Seoul, Incheon, and Gyeonggi province. To measure the research variables, the Peer Conflict Scale (Marsee, Kimonis, & Frick, 2004), the Psychological Control Scale (Barber, 1996) and the Children's Rejection Sensitivity Questionnaire (Downey, Lebolt, $Rinc\acute{o}n$, & Freitas, 1998) were used. The data were analyzed by means of descriptive statistics and t -tests. Also, structure equation model (SEM) were used to examine the mediating role of rejection sensitivity. Results: The results of this study were as follows. First, the level of paternal psychological control increased the level of children's relational aggression whereas the level of maternal psychological control had no significant effect on it. In addition, the level of rejection sensitivity had a significant positive influence on the level of relational aggression. These tendencies were observed on both boys and girls. Second, only for boys, rejection sensitivity in upper elementary school students partially mediated the relation between paternal psychological control and relational aggression. Also, for both boys and girls, rejection sensitivity completely mediated the relation between maternal psychological control and relational aggression. Conclusion: In conclusion, the higher the level of paternal psychological control, the higher the level of children's rejection sensitivity, and subsequently the higher the level of their relational aggression.

• Korean Journal of Child Studies
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• v.29 no.4
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• pp.79-95
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• 2008

This study investigated developmental pathways mediating effects of child abuse on peer rejection. Participants were 904 poor children aged 10-15 from 16 nationwide cities/provinces who receive financial sponsorship from Childfund in cooperation with the Ministry for Health, Welfare and Family Affairs. Structural equation modeling was employed for statistical analyses. Results showed that child abuse was directly associated with heightened risk of rejection by peers; the relationship was indirectly mediated by aggression and cognitive ability. The hypothesized partially mediated model had a better model fit than the fully mediated model. Aggression and low cognitive ability, significant effects of abuse, were associated with peer rejection. Social withdrawal, also associated with child abuse, did not account for the association between abuse and peer rejection.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.11 no.3
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• pp.211-216
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• 1986

This paper presents theoretical analysis and experimental results on an improved interference rejection circuit in the presence of continuous wave interference at center frequency, particularly in a wide-band communication systems. This circuit is based upon a phase locked loop for estimating the CW interference phase and the MSE technique to minimize the estimation error. Therefore, the introduced rejection circuit that minimized the estimated phase error outperforms the rejection circuit with phase estimation only. As a result of experiment, we confirm that this proposed rejection circuit gives a high degree of interference rejection performances when the input J/S is large.

• Korean Membrane Journal
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• v.5 no.1
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• pp.54-60
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• 2003

The rejection properties and flux rates of silica nanoparticles in ultrafiltration membranes has been investigated. Cross-flow permeation experiments were conducted using polycarbonate track-etch flat membranes with pore sizes of 30 and 50 nm, and a silica nanoparticle solute with particle sizes of 5 and 18 nm with narrow size distributions. The fluxes and rejection factors were investigated at various particle concentrations, cross-flow velocities, pH, and ionic strengths of solution. Even though the size of the silica nanoparticles was much smaller than that of the membrane pores, the observed rejection rates were very high compared with those for a similar-sized polymer (dextran). The observed rejection rate decreased with increasing ionic strength, which implies that the transport mechanism of the silica nanoparticles is significantly influenced by electrostatic repulsion between particles and membranes.

• Korean Journal of Child Studies
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• v.29 no.2
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• pp.57-71
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• 2008

This study examined the influences on maternal acceptance-rejection and mediating effects of parenting stress. Participants were 150 mothers of children aged 3 to 6 in Seoul and Jeju. Research questions were analyzed by structural equation modeling. Results showed that children's age, congenital diseases or anomalies, planned pregnancy, and father's occupation influenced maternal acceptance-rejection directly. Mothers' perceived treatment in childhood and fathers' age influenced parenting stress; parenting stress, in turn, influenced maternal acceptance-rejection. Fathers' age influenced parenting stress negatively; parenting stress, in turn, influenced maternal acceptance-rejection positively.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.15-18
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• 2004

Computational fluid dynamics (CFD) was applied to modeling particle dynamics in microfiltration (MF). The rejection properties of poly methylmethacrylate (PMMA) and polystyrene (PS) were calculated. Calculated rejection (R) of PMMA was independent with the porosity of the membrane, and the R was constant in the range of volume flux between $1\times 1-^{-4}-1\times 10^{-2}$ m/s. These observations were in quantity agreement with our experimental observations. The dependence of PMMA and PS rejection on the ratio of particle diameter and pore diameter were good agreement with the experimental values, which suggesting that the validity of CFD simulation to evaluate rejection of particle in MF membranes. Change of rejection of PMMA as a function of time was molded based on the CFD result which explained well the experimental observation.

• Journal of electromagnetic engineering and science
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• v.6 no.1
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• pp.18-23
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• 2006

In this paper, we demonstrate a fully integrated X-band image rejection down converter, which was developed using InGaP/GaAs HBT MMIC technology, consists of two single-balanced mixers, a differential buffer amplifier, a differential YCO, an LO quadratue generator, a three-stage polyphase filter, and a differential intermediate frequency(IF) amplifier. The X-band image rejection downconverter yields an image rejection ratio of over 25 dB, a conversion gain of over 2.5 dB, and an output-referred 1-dB compression power$(P_{1dB,OUT})$ of - 10 dBm. This downconverter achieves broadband image rejection characteristics over a frequency range of 1.1 GHz with a current consumption of 60 mA from a 3-V supply.

• Journal of Korean Physical Therapy Science
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• v.9 no.1
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• pp.95-102
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• 2002

The present study focuses on the relation of the attitudes of university students to disabled by using modified disability factor scales(DFS, Siller). As for the attitude areas, it relies on the eight categories DFS provides. The 8 categories that specify each attitude area are: generalized rejection, distressed identification, inferred emotional consequences, imputed functional limitation, authoritarian virtuousness, rejection of intimacy, interaction strain, mainstreaming. This study is based on a series of questionnaire researches conducted on 322 students, over the period from October 19th to November 14th, 2001. The questionnaire carries 50 items, covering the 8 attitude areas and each item has 5 choices. The subjects' responses to each of the areas are examined in their relations to the four conditions, as they are analysed by t-test and one way ANOVA. The conclusion drawn from the research are as follows: 1. There is no significant difference between the students of the department concerned with the problem of disability, and those of the department unconcerned. But the responses are significantly different in the three areas of generalized rejection, rejection of intimacy and interaction strain(1st condition, P<.05). 2. The responses are significantly different in 6 areas except for the two, distressed identification and inferred emotional consequences, between the students who have volunteered services as helpers of the disabled and those who have no such experiences(2nd condition, P<.05). 3. the responses are significantly different between those who have volunteered long-time services and those who are far less experienced(3nd condition, P<.05). 4. There is no significant difference, whether the subjects have disabled persons around them or not. But generalized rejection, authoritarian virtuousness, rejection of intimacy, interaction strain & mainstreming show significant differences(4th condition, P<.05). 5. Generalized rejection, rejection intimacy and interaction strain show significant differences in every pair of the 4 condition. 6. Distressed identification and inferred emotional consequence show no significant difference between the two conditions in every pair of the 4 considerations.

• Microbiology and Biotechnology Letters
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• v.27 no.4
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• pp.320-326
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• 1999

The effects of operating pressure, lactate concentration, impurities, and pH on solution flux and lactate rejection in nanofiltration were investigated with model sodium lactate solutions (lactate 10~200g/L) as a model system. In the tested range of pressure(80~140 psig), the solution flux was observed to be proportional to the operating pressure and the rejection of lactate increased only slightly with the pressure. Both of the flux and the rejection decreased with lactate concentration, while the recovery rate of lactate increased. The effects of glucose and yeast extract as impurities on lactate rejection were negligible, but the flux decreased significantly with the addition of yeast extract. At low lactate concentrations, the rejection of lactate increased with pH due to the increased repulsion (Donnan exclusion effect) between lactate ions and membrane surface. But, at high lactate concentrations, the donnan effect was observed to be overwhelmed by the effect of sodium ions added to adjust the pH, and the rejection of lactate decreased with pH. When fermentation broth containing about 89g/L of lactate was nanofiltered, the flux and the rejection of lactate were 2.8L/$m^2$h and 5%, respectively at 120psig. Both of them were slightly lower than those with model solutions. The recovery rate was 2.6mol/$m^2$h.