• Title/Summary/Keyword: Cheong-song

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Preparation of Hard Coating Solutions with High Refractive Index for Polycarbonate Sheet by the Sol-Gel Method (Sol-Gel 법에 의한 Polycarbonate 시트에 적용 가능한 고굴절률을 보이는 하드코팅 용액의 제조)

  • Cheong, Il Yeop;Cho, Kyung In;Cheong, Sang Hyuk;Park, Hyo Nam;Song, Ki Chang
    • Korean Chemical Engineering Research
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    • v.45 no.4
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    • pp.335-339
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    • 2007
  • In order to overcome the problem of poor hardness of transparent polycarbonate (PC) sheets, organic-inorganic hybrid hard coating solutions, which show a high refractive index above 1.58, were made by the sol-gel method. These hybrid coating solutions were obtained from mixture of titanium tetraisopropoxide (TTIP), and (3-glycidoxypropyl)trimethoxysilane (GPTMS). The PC sheets were spin-coated, and cured at $120^{\circ}C$ for 2 hr. Change of refractive index in the range of 1.53-1.61 was obtained by varying the GPTMS content. The refractive index of the coated film decreased with increasing the GPTMS content, while the pencil hardness of the coated film was found to increase with increasing the GPTMS content.

Property Evaluation of the Concrete Replacing 5-13mm Recycled Coarse Aggregates (5~13mm 입도분급 순환 굵은 골재 혼합사용에 따른 콘크리트의 특성평가)

  • Han, Min-Cheol;Song, Young-Wo
    • Journal of the Korea Institute of Building Construction
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    • v.17 no.1
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    • pp.55-61
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    • 2017
  • This paper is to investigate experimentally the effect of substitution of recycled coarse aggregate(RCA) under 13mm on the engineering properties of the concrete using gap graded coarse aggregates. Concretes with 0.4 of water to cement ratio(W/C) were fabricated to achieve 30MPa of design strength with coarse aggregate over 13mm in size with the maximum size of 25mm. RCA was substituted for coarse aggregate over 13mm from 10% to 50% and crushed coarse aggregate under 13mm was also substituted for coarse aggregate over 13mm from 20% to 40%, respectively. Test results indicated that the replacement of RCA up to 20% resulted in an increase of fluidity and strength. It also caused a decrease in the drying shrinkage due to dense packing effect by achieving continuous grading of mixed aggregates. For practical application of RCA, when properly substituted, the use of RCA enabled the concrete to reduce water contents and sand to aggregate ratio in mixing design stage of the concrete. And, it can also enhance the compressive strength of the concrete.

Floral Nectary-specific Gene NTR1 Encodes a Jasmonic Acid Carboxyl Methyltransferase

  • Seo, Hak Soo;Song, Jong Tae;Koo, Yeon Jong;Jung, Choonkyun;Yeu, Song Yion;Kim, Minkyun;Song, Sang Ik;Lee, Jong Seob;Hwang, Ingyu;Cheong, Jong-Joo;Choi, Yang Do
    • Journal of Applied Biological Chemistry
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    • v.44 no.3
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    • pp.119-124
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    • 2001
  • NTR1 gene of Brassica campestris L. ssp. perkinensis encodes a floral nectary-specific methyltransferase. In this study, the NTR1 cDNA was expressed in E. coli to examine the enzymatic characteristics of the protein product. The GST-NTR1 fusion protein was purified to near homogeneity, showing that the size of NTR1 was 44 kDa. The protein reacted specifically with jasmonic acid (JA), consuming methyl group from S-adenosyl-L-methionine (SAM). GC-MS analysis revealed that the compound produced was authentic methyl jasmonate (MeJA), suggesting that NTR1 is an S-adenosyl-L-methionine: jasmonic acid carboxyl methyltransferase. Km values of NTR1 for JA and SAM were 38.0 and $6.4{\mu}M$, respectively. Optimal activity of the NTR1 was observed at $20^{\circ}C$, pH 7.5, in the presence of 100-150 mM KCl. Thus, kinetic properties, thermal characteristics, optimal pH, and ion-dependency of the NTR1 activity were almost identical to those of Arabidopsis JA methyltransferase JMT, indicating that these two proteins are orthologues of each other.

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Effects of Mg Suppressor Layer on the InZnSnO Thin-Film Transistors

  • Song, Chang-Woo;Kim, Kyung-Hyun;Yang, Ji-Woong;Kim, Dae-Hwan;Choi, Yong-Jin;Hong, Chan-Hwa;Shin, Jae-Heon;Kwon, Hyuck-In;Song, Sang-Hun;Cheong, Woo-Seok
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.2
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    • pp.198-203
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    • 2016
  • We investigate the effects of magnesium (Mg) suppressor layer on the electrical performances and stabilities of amorphous indium-zinc-tin-oxide (a-ITZO) thin-film transistors (TFTs). Compared to the ITZO TFT without a Mg suppressor layer, the ITZO:Mg TFT exhibits slightly smaller field-effect mobility and much reduced subthreshold slope. The ITZO:Mg TFT shows improved electrical stabilities compared to the ITZO TFT under both positive-bias and negative-bias-illumination stresses. From the X-ray photoelectron spectroscopy O1s spectra with fitted curves for ITZO and ITZO:Mg films, we observe that Mg doping contributes to an enhancement of the oxygen bond without oxygen vacancy and a reduction of the oxygen bonds with oxygen vacancies. This result shows that the Mg can be an effective suppressor in a-ITZO TFTs.

Expression of Plasminogen Activators in Uterine Epithelial Cells of Pre-ovulatory Phase in Pigs (돼지의 배란 전 자궁내막 상피세포 내 Plasminogen Activators의 발현)

  • HwangBo, Yong;Lee, Sang-Hee;Cha, Hye-Jin;Song, Eun-Ji;Lee, Seung-Tae;Lee, Eun-Song;Cheong, Hee-Tae;Yang, Boo-Keun;Park, Choon-Keun
    • Journal of Embryo Transfer
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    • v.28 no.3
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    • pp.257-263
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    • 2013
  • The endometrium undergoes a cyclic growth and tissue remodeling as changes of epithelial cells, and plasminogen activators (PAs) are related to endometrium tissue remodeling. This study was to evulate expression of urokinase-type plasminogen activator (uPA) and tissue-type plasminogen activator (tPA) in porcine uterine epithelial cells. In results, the uPA and tPA were expressed in uterine tissue, epithelium and secretory glands in porcine endometrial cell. In addition, the uPA and tPA were expressed in cultured epithelial cells, and it were mainly expressed in cytoplasm. In porcine uterine tissue and epithelial cells, uPA activity was higher than activity in tPA. In PAs mRNA expression levels, uPA mRNA level was significantly higher than tPA mRNA level (P<0.05). The fluorescence intensity of uPA protein was also higher than fluorescence intensity of tPA protein, and uPA protein expression was significantly higher than in tPA protein expression (P<0.05). Therefore, we suggest that a physiological function in porcine uterine epithelial cells should be more influenced by uPA than in tPA during pre-ovulatory phase.

Verification of Reliability and Validity of KPCS-1 and Estimation of Nursing Time Conversion Index (한국형 환자분류도구-1(KPCS-1)의 신뢰도와 타당도 검증 및 간호시간 환산지수 산출)

  • Song, Kyung Ja;Kim, Eun Hye;Yoo, Cheong Suk;Park, Hyeoun Ae;Song, Mal Soon;Park, Kwang Ok
    • Journal of Korean Clinical Nursing Research
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    • v.16 no.2
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    • pp.127-140
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    • 2010
  • Purpose: This study was performed to verify reliability and validity of Korean Patient Classification System for nurses(KPCS-1), to estimate nursing time conversion index, and to classify patients into groups according to KPCS-1 scores. Methods: KPCS-1 was revised from KPCS by a professional review team. Interrater reliability and construct validity of KPCS-1 were verified by data from 433 patients. Direct and indirect nursing time of 204 patients were measured by stopwatch observation and self reports for 24 hours. Nursing time conversion index was calculated. Results: KPCS-1 consisted of 12 area, 50 nursing activities, and 73 items. The interrater reliability was tested between two nurse group (r=.88, p<.001) and construct validity was verified according to medical department (F=10.97, p<.001) and patient pattern (F=5.54, p=.001). The correlation of nursing time and classification score was also statistically significant (r=.56, p<.001). The nursing time conversion index was 9.03 minutes per 1 classification score. The patients were classified into 4 groups by the classification scores. Conclusion: KPCS-1 can be a useful factor type patient classification system for general ward. Further study is needed to evaluate validity and reliability for refining KPCS-1 and to develop ways connecting the scores with nursing outcomes.

Subtotal Resection of the Giant Paraprostatic Cyst with Omentalization in a Dog: A Case Report

  • Youngrok Song;Youngsoo Hong;Solji Choi;Woojin Song;Hyunjung Park;Joo-Myoung Lee;Jungha Lee;Jongtae Cheong
    • Journal of Veterinary Clinics
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    • v.40 no.3
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    • pp.230-237
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    • 2023
  • A 6-year-old intact male Cane Corso dog weighing 40 kg with a 2-month history of dysuria, dyschezia, anorexia, intermittent panting, and penile discharge presented to the Veterinary Medical Teaching Hospital of Jeju National University. Examination revealed a giant paraprostatic cyst (PPC) that occupied a large part of the abdomen and caused displacement of organs. Radiography, ultrasound, and computed tomography (CT) scans confirmed that the PPC had spread to the pelvic regions. Subtotal resection was performed, leaving two sites with PPC remnants. One site was the prostate gland, which communicated with, and adhered to, the PPC; the other site was the pelvic region, where the PPC had spread. The reason for leaving two remnants was that an anatomical approach for complete resection was difficult, and to avoid complications associated with prostatic urethra damage. Routine omentalization and castration were performed. Partial cystectomy was performed because of the presence of a diverticulum-like lesion in the ventral part of the urinary bladder. The patient's clinical symptoms, including dysuria, completely resolved, and voluntary urination was possible 1 day post-operatively. Histopathological examination revealed osseous metaplasia of the PPC. The patient was well-managed and had no post-operative complications or recurrence until day 180 of follow-up.

Surgical Resection and Polypropylene Mesh Reconstruction for Canine Chest Wall Soft Tissue Sarcoma

  • Youngsoo Hong;Youngrok Song;Woojin Song;Myung-Chul Kim;Joo-Myoung Lee;Hyunjung Park;Jiwhan Moon;Jongtae Cheong
    • Journal of Veterinary Clinics
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    • v.41 no.1
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    • pp.24-29
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    • 2024
  • A 6-year-old spayed female French Bulldog presented with a left-sided chest wall tumor. Physical examination revealed that the tumor was firmly adhered to the chest wall. A preoperative punch biopsy of the tumor revealed a grade 2 soft tissue sarcoma (STS). On computed tomography, the tumor's dimensions were assessed as 6.5 × 5.7 × 3.5 cm, and it exhibited invasiveness near the tissue surrounding the ninth rib. The tumor size was large in comparison to the dog's chest wall area. Hence, if the traditional wide-margin resection surgery were to be performed, primary wound closure seemed impractical and could potentially result in respiratory function complications. Therefore, considering the extent of tumor invasion and grade, deep margins were established to include the removal of the eighth to tenth ribs, and a 1-cm lateral margin was designated to enable primary wound closure. To reconstruct the chest wall, polypropylene mesh was attached to the adjacent ribs and the remaining muscles were sutured and covered over the mesh. The dog exhibited a rapid recovery beginning the day after the operation. Postoperative biopsy confirmed that the tumor was a grade 2 STS, and the surgical margins were evaluated as incomplete. The owner chose to pursue follow-up observation instead of chemotherapy. In this study, the surgical approach was chosen based on the importance of functional recovery after surgery. Recent research indicates that the tumor grade is more critical for postoperative prognosis than the extent of surgical margins when removing an STS.

Falcarindiol, a Polyacetylenic Compound Isolated from Peucedanum japonicum, Inhibits Mammalian DNA Topoisomerase I

  • Lee, Gwang;Park, Hyoung-Gun;Choi, Mi-Lim;Kim, Young-Ho;Park, Yong-Bok;Song, Kyung-Sik;Cheong, Chaejoon;Bae, Young-Seuk
    • Journal of Microbiology and Biotechnology
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    • v.10 no.3
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    • pp.394-398
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    • 2000
  • A methanol extract of the root of Peucedanum japonicum, used as a medicinal herb, showed an inhibitory effect on mammalian topoisomerase I activity. The methanol extract was suspended in ethyl acetate, and a topoisomerase I inhibitor in the organic soluble fraction was then isolated by silica gel and thin layer chromatography. The topoisomerase I inhibitory compound was indentified as falcarindiol based on the analysis of EI-MS, $^1$H and \ulcornerC NMR spectroscopy. This inhibitory showed cytotoxicity against human leukemia Jurkat T and HL60 cells with an IC\ulcorner value of 7 $\mu\textrm{g}$/ml. These results suggest the possibility of falcarindiol as a new anticancer agent which can be expected to have a synergistic effect on other anticancer drugs. In addition, the present data show that falcarindiol has antifungal, yet not antibacterial, activity.

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A Study on the Characteristic Analysis of Brushless DC Motor Using FEM (유한요소법을 이용한 브러시레스 DC 모터의 특성 해석에 관한 연구)

  • Cheong, Shin-Young;Song, Yu-Seok;Lee, Ju;Jang, Seok-Joong;Park, Geon-Hee
    • Proceedings of the KIEE Conference
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    • 2002.07b
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    • pp.920-922
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    • 2002
  • This paper investigates the cogging torque reduction in a brushless DC(BLDC) motor having an inner-rotor with surface-mounted segment-type permanent magnets. The kind of magnets for the BLDC motor could have different waveforms of magnetization such as square, trapezoidal and sinusoidal form. This paper discusses the effect of the unsymmetrical magnetization distribution in the segment-type permanent magnet, which is able to obtain through a segment structure that the number of poles per segments is 2 ($N_p/N_s$), on the cogging torque and EMF waveform. Where the existing magnetizer fixture for the square-type magnetization is used to magnetize the magnets in two segment structures of $N_p/N_s$ = 1 and 2. The effectiveness of the proposed designs had been confirmed by comparing cogging torque, and EMF waveform between conventional and new models which are analyzed by Finite Element Method (FEM).

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