• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.18 no.7
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• pp.704-709
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• 2007

In this paper, a CPW band-pass filter with a rejection band is proposed for UWB(Ultra-Wideband) communication systems. The proposed filter has a band-pass characteristic of wide-band by inserting only a slot in $50{\Omega}$ transmission line. To obtain the band-rejection function at WLAN frequency band($5.15{\sim}5.725GHz$), the designed filter is combined with folded slot resonators on the ground plane of the CPW structure. The fabricated CPW band-pass filter shows a compact size of $15.35{\times}13.60mm$, a wide passband of 2.8 GHz to 9.8 GHz and the narrow stop-band of 5.15 GHz to 5.71 GHz for 3-dB bandwidth. Also, the measured group delay is less than 400 psec throughout the operation frequency band except the rejection band.

• Reproductive and Developmental Biology
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• v.41 no.3
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• pp.57-63
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• 2017

Xenotransplantation is proposed as a solution to the problem of organ shortage. However, transplantation of xenogeneic organs induces an antigen-antibody reaction in ${\alpha}$-1,3-gal structure that are not present in humans and primates, and thus complement is also activated and organs die within minutes or hours. In this study, we used FasL gene, which is involved in the immune response of NK cell, and US11, which suppresses MHC Class I cell membrane surface expression, to inhibit cell mediated rejection in the interspecific immunity rejection, and also hDAF(CD55) was introduced to confirm the response to C3 complement. These genes were tranfeced into Korean native pig fetal fibroblasts using pCAGGS vector. And cytotoxicity of NK cell and human complement was confirmed in each cell line. The US11 inhibited the cytotoxicity of NK cell and, in addition, the simultaneous expression of US11 and Fas ligand showed excellent suppress to T-lymphocyte cytotoxicity, hDAF showed weak resistance to cytotoxicity of natural killer cell but not in CD8+ CTLs. Cytotoxicity study with human complement showed that hDAF was effective for reducing complement reaction. In this studies have demonstrated that each gene is effective in reducing immune rejection.

• Journal of Veterinary Clinics
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• v.28 no.1
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• pp.63-70
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• 2011

To consider the iliac fossa as the vascular anastomosis site of kidney transplantation for the short-term study of acute rejection in pigs. Twelve domestic pigs weighing 39~48 kg underwent heterotopic renal allgraft transplantation. The experimental animals were divided into 2 groups in terms of renal vascular anastomosis site; the external iliac artery and vein were used in iliac fossa model (n = 6), the abdominal aorta and the caudal vena cava inferior to the kidney were used in abdominal cavity model (n = 6). Renal function was evaluated by daily measurement of plasma creatinine and BUN concentrations. The experiments' health including postoperative complications was also assessed daily for 8 days after transplantation. After euthanazation gross and histopathologic analysis was performed. All six pigs in iliac fossa model developed neuropraxia and lameness of the ipsilateral pelvic limb. However, no necrosis was observed in any pigs. In the abdominal cavity model, durations of both the surgical operation and the vascular anastomosis were significantly longer than those in the iliac fossa model. Furthermore, ischemia injury of the transplanted kidney was increased in abdominal cavity model, which induced accelerated-acute immune response from day 4 after transplantation. Despite of pelvic limb complication, the iliac fossa model showed more advantages including not only less ischemia time related to easy vascular anastomosis, but also less immune response during the acute rejection period. The results indicate that the iliac fossa model may be appropriate to the study of acute rejection in porcine kidney transplantation.

• The Korean Journal of Elementary Counseling
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• v.11 no.3
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• pp.351-369
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• 2012

The purpose of this study is to examine the psychometric properties of the Korean Children's Rejection Sensitivity Questionnaire (K-CRSQ). In order to investigate the reliability and validity of the K-CRSQ, the data were collected from 286 elementary students. The results are as follow : Internal consistency and test -retest reliability of the K-CRSQ were .83~.89, .72~.79, respectively. To test the convergent and discriminant validity, participants were separated into two samples and administered the K-CRSQ and ten validity indices. The correlation of K-CRSQ and validity indices scores suggested that the convergent and discriminant validity are high. High rejection sensitivity group revealed high score on intentional attribution, depression, anxiety, and aggression. In contrast, low rejection sensitivity group revealed high score on self-esteem, perceived competence, and social support. The results were compared with previous studies and the implication and limitation were discussed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.37 no.7A
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• pp.545-551
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• 2012

In this paper, K-band multi-channel receiver was designed and fabricated for low noise amplification and down conversion to L-band. The fabricated multi-channel receiver incorporates GaAs-HEMT LNA(Low noise amplifier) which provides less than a 2 dB noise figure, IR(Image Rejection) Filter for rejection of image frequency, IR(Image rejection) mixer to reject a image frequency and improve an IMD(Intermodulation Distortion) characteristic. Test results of the fabricated multi-channel receiver show less than a 3.8 dB noise figure, conversion gain of more than 27dB, and IP1dB(Input 1dB Gain Compression Point) of -9.5 dB and over.

• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.8 no.2
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• pp.14-20
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• 2012

Full load rejection capability of nuclear power plant depends primarily on steam dump capacity (SDCAP) and steam generator level control capability. Recently, Ulchin Units 1&2 have performed stretched power uprate (SPU) and replacement steam generator (RSG) projects, which increase the power by 4.5 percent. They change major design or operating parameters and especially reduces steam dump capacity at full power due to increase of the steam flow. The reduction of SDC after SPU results in degradation of heat removal capability in full load rejection transients. Therefore, we should perform evaluation to determine whether reactor trips occur in large load rejection transients. Uchin Units 1&2 have experienced full load rejection (FLR) three times from 2004 to 2010. Operating data from the plant occurrence of FLR at Ulchin Units 1&2 showed that steam generator (SG) level transients were limiting in point of reactor trip. However the plant had never reached reactor trip in the FLR and successfully continued in house load operation. The parameters and setpoints for the SG will be changed if the SG is replaced. Therefore, we evaluated the appropriateness of steam dump, main feedwater and steam generator water level control system preventing the plant from reactor trip in case of FLR by the parameter sensitivity study whether SG water level operated smoothly after SPU and RSG projects.

• Membrane Journal
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• v.16 no.1
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• pp.59-67
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• 2006

Biodegradable amphiphilic polymer was synthesized for removing hydrophobic pollutants(phenol, 4-nitrophenol, benzene, and toluene) and metal ions ($Cs^{+},\;Mg^{2+},\;Cu^{2+},\;Ni^{2+}$, and $Cr^{3}$). The methoxy poly(ethylene glycol)s with different molecular weights (1,100 and 5,000) were used as a hydrophilic segment. The rejection ratio improved in the relatively high molecular weight of MPEG. The rejection ratio of biodegradable nanoparticles without pollutants was over 98%. In removal of hydrophobic pollutants, the rejection ratio increased with the hydrophobic properties. The electron valence affects the rejection ratio of metal ions, indicating rejection ratio was ordered as $3^{+}>2^{+}>1^{+}$.

• Korean Journal of Transplantation
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• v.32 no.4
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• pp.75-83
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• 2018

Background: This study was designed to analyze the clinical usefulness of mycophenolic acid trough concentration monitoring in kidney transplantation patients who were maintained with cyclosporine. Methods: The data of patients who underwent mycophenolic acid trough concentration monitoring after their first kidney transplant between November 2006 and August 2013 and were prescribed with cyclosporine, mycophenolate, and methylprednisolone were reviewed retrospectively. Cox analysis was used to analyze the risk factors for acute rejection within 1 year post-transplantation. Results: Among 90 patients, 41 (45.6%) achieved both the target levels of cyclosporine and mycophenolic acid, while three patients (3.3%) failed to achieve the target level of either cyclosporine or mycophenolic acid. Nine patients (10.0%) only achieved the mycophenolic acid target level and 37 patients (41.1%) only achieved the cyclosporine target level. While patients who achieved only the mycophenolic acid target concentration had no statistically increased risk compared to patients who achieved both target levels (hazard ratio [HR], 1.569; 95% confidence interval [CI], 0.316 to 7.778; P=0.581), patients who only achieved the cyclosporine target concentration showed an increased risk of rejection compared to the both achievement group (HR, 4.112; 95% CI, 1.583 to 10.683; P=0.004). Patients who had no achievement in the target levels showed significantly increased rejection risk compared to the patients who achieved both target levels (HR, 17.811; 95% CI, 3.072 to 103.28; P=0.001). Conclusions: Mycophenolic acid trough concentration monitoring combined with cyclosporine trough concentration monitoring is useful for avoiding acute cellular rejection if the first 1 year post-transplantation.

• Korean Journal of School Psychology
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• v.18 no.3
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• pp.351-370
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• 2021

This study investigated the effect of parental psychological control on relational aggression among middle school students, the mediating effects of rejection sensitivity and friendship jealousy, and whether there were differences in these variables by the demographic characteristics of gender and family form. Data of 554 middle school students living in Daegu and Gyeongsangbuk-do were used for the final analysis. There were two major results. The first major result was what rejection sensitivity and friendship jealousy sequentially mediated the relationship between parental psychological control and relational aggression. The second major result was gender differences which was shown by a multi-group analysis to examine in the path from parental psychological control to rejection sensitivity, the path from parental psychological control to relational aggression, and the path from friendship jealousy to relational aggression. This study was meaningful in that it expanded the understanding of relational aggression and identified directions for therapeutic interventions.

• Membrane and Water Treatment
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• v.1 no.1
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• pp.1-12
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• 2010

Membrane distillation process was used for purification of pre-treated natural water (tap water). The rejection of inorganic and organic compounds in this process was investigated. The obtained rejection of inorganic solutes was closed to 100%, but the volatile organic compounds (VOCs) diffused through the membrane together with water vapour. The content of trihalomethanes (THMs) in the obtained distillate was two-three fold higher than that in the feed, therefore, the rejection of the total organic compounds present in the tap water was reduced to a level of 98%. The intensive membranes scaling was observed during the water separation. The morphology and composition of the fouling layer was studied using scanning electron microscopy coupled with energy dispersion spectrometry. The influence of thermal water pre-treatment performed in a heat exchanger followed by filtration on the MD process effectiveness was evaluated. This procedure caused that significantly smaller amounts of $CaCO_3$ crystallites were deposited on the membrane surface, and a high permeate flux was maintained over a period of 160 h.