• East Asian mathematical journal
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• 제33권2호
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• pp.177-197
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• 2017

The purpose of this study is to investigate and analyze the understandings of elementary pre-service teachers about 'estimation' in the elementary mathematics. Together with this analysis, we identify elementary pre-service teacher's Mathematical Pedagogical Contents Knowledge(MPCK), especially focusing to Subject Matter Knowledge(SMK). In order to this goals, we investigate contents relating to 'estimation' from $1^{st}$ curriculum to 2009 revised curriculum and compare 'rounding up', 'rounding off', 'rounding' in the elementary mathematics textbooks. As results of investigations, 'estimation' has been teaching at the 'Measurement' domain from $3^{rd}$ curriculum, but contexts of measuring weaken from $7^{th}$ curriculum. 'Rounding up(off)' is defined three types in the textbooks from $1^{st}$ to 2009 revised curriculum. And we examine elementary pre-service teachers through the questions on these 'estimation' contents. On the analysis of pre-service teacher's understanding relating MPCK, four themes is summarized as followings; the understanding of '0' in the 'rounding up', the cognitive gap between 'rounding up' and 'rounding off', the difference of percentage of correct answers according to types of question in the 'rounding up', and the difference between the definition of 'rounding up' and the definition of 'rounding'.

• ETRI Journal
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• 제26권6호
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• pp.657-660
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• 2004

We propose a fine phase tuner and a rounding processor for a numerically controlled oscillator (NCO), yielding a reduced phase error in generating a digital sine waveform. By using the fine phase tuner presented in this paper, when the ratio of the desired sine wave frequency to the clock frequency is expressed as a fraction, an accurate adjustment in representing the fractional value can be achieved with simple hardware. In addition, the proposed rounding processor reduces the effects of phase truncation on the output spectrum. Logic simulation results of the NCO using these techniques show that the noise spectrum and mean square error (MSE) for eight output bits of a 3.125 MHz sine waveform are reduced by 8.68 dB and 5.5 dB, respectively, compared to those of the truncation method, and 2.38 dB and 0.83 dB, respectively, compared to those of Paul's scheme.

• 방송공학회논문지
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• 제15권6호
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• pp.853-867
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• 2010

IPTV, DMB 등과 같은 방통융합 기반 멀티미디어 서비스에서는 고성능 비디오 인덱싱을 위한 썸네일 기술이 요구되므로 H.264/AVC 비트스트림으로부터 직접 썸네일을 추출하는 방법이 제안되었다. 그러나 화소 공간에서 정의한 일반화 수식을 주파수 공간으로 변환하는 과정에서 H.264/AVC에 정의된 변환 및 양자화, 그리고 인트라 예측의 반올림을 고려하지 않음으로써 썸네일 화질을 저하시키는 문제점이 있다. 본 논문에서는 H.264/AVC 비트스트림에서의 새로운 썸네일 추출 방법을 제안한다. 제안하는 방법은 H.264/AVC 핵심 변환을 기반으로 주파수 공간에서의 썸네일 추출 방법을 이론적으로 정리하고 확률적 방법으로 인트라 예측의 반올림 보상 방법을 제시한다. 제안한 방법을 통해 얻은 썸네일은 참조 복호화기를 통해 얻은 썸네일과 주관적 화질은 크게 차이 나지 않으며 이전에 제안된 방법과 비교하여 주관적 화질 향상과 최대 8.66 dB의 PSNR 이득을 얻었다.

• 생명과학회지
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• 제23권10호
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• pp.1252-1259
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• 2013

인간 암세포의 생육에 미치는 혈전용해효소(BK-1)의 영향을 조사하기 위해, 세포증식, 생존력, 형태변화 및 apoptosis 유도 등을 포함한 여러 가지 생화학적 실험을 하였다. 그 결과, AGS 인간 위장 암세포 및 T24 인간 방광 암세포상에의 BK-17 처리는 그 암세포들의 생존력 및 생율을 농도의존적 방법으로 감소시켰다. 현미경 관찰은, BK-17 처리에 의한 항 생육 효과는 막 수축, 세포의 rounding up, apoptotic bodies와 같은 형태학적 변화를 나타내었다. 특히, RT-PCR과 Western blotting data는, BK-17 처리가 항 apoptosis Bcl-2 군들 특히 Bcl-2, and $Bcl-X_L$의 down-regulation 그리고 AGS 세포에서, apoptosis 촉진 매개체 Bax와 Bad의 up-regulation를 유도했다는 것을 보여주었다. BK-17에 의해 유도된 AGS 세포의 apoptosis는 caspase-3, caspase-8 그리고 caspase-9의 단백질가수분해 활성과 관련이 있었다. 이상의 결과를 볼 때, BK-17은 apoptotic cell death의 유도와 밀접한 관련이 있다는 것을 보여주고 있다.

• ALGAE
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• 제21권1호
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• pp.103-107
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• 2006

Rhodochorton purpureum 4187 from Jeju Island, Korea may have a sexual life history similar to that seen by other investigators working on other strains around the world. In culture short days (8:16, 11:13, 12:12 LD) at 10-15°C induced tetrasporogenesis. Discharged spores were observed with time lapse videomicroscopy. They showed a slight amoeboid movement for 2-3 minutes before rounding up and settling. Tetrasporelings develop into male and female gametophytes. No fertilisation was observed. Tetrasporangia often were borne on carpogonial clusters of females but no discharged spores were seen. Isolate 4241 from San Juan I., Washington, USA grew well in most conditions tested but did not reproduce in short days (8:16, 11:13, 12:12 LD) at 10-15°C.

• 전자공학회논문지B
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• 제30B권6호
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• pp.49-58
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• 1993

Extended reduced difference pyramid (ERDP) is proposed for lossless progressive image transmission, which is based on a new transform called rounded-transform(RT). The RT is a nonlinear and reversible transform of integers into integers utilizing two kinds of the rounding operations such as round up and down. The ERDP can be obtained from an N-poing RT or a series of RTs of both. For the performance evaluation, the entropy of the difference images to be transmitted is used as a lower bound transmission rate. Two examples of the ERDP can be easily shown, which is more effective in the entropy than the ordinary RDP.

• Journal of Microbiology and Biotechnology
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• 제22권1호
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• pp.50-57
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• 2012

Phospholipase C-${\gamma}l$ (PLC-${\gamma}l$) expression is associated with cellular transformation. Notably, PLC-${\gamma}$ is up-regulated in colorectal cancer tissue and breast carcinoma. Because exotoxins released by Clostridium botulinum have been shown to induce apoptosis and promote growth arrest in various cancer cell lines, we examined here the potential of Clostridium difficile toxin A to selectively induce apoptosis in cells transformed by PLC-${\gamma}l$ overexpression. We found that PLC-${\gamma}l$-transformed cells, but not vector-transformed (control) cells, were highly sensitive to C. difficile toxin A-induced apoptosis and mitotic inhibition. Moreover, expression of the proapoptotic Bcl2 family member, Bim, and activation of caspase-3 were significantly up-regulated by toxin A in PLC-${\gamma}l$-transformed cells. Toxin A-induced cell rounding and paxillin dephosphorylation were also significantly higher in PLC-${\gamma}l$-transformed cells than in control cells. These findings suggest that C. difficile toxin A may have potential as an anticancer agent against colorectal cancers and breast carcinomas in which PLC-${\gamma}l$ is highly up-regulated.

• 동의생리병리학회지
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• 제18권4호
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• pp.1147-1152
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• 2004

To investigate the anti-cancer effects of aqueous extract of Cheonkumwikyung-tang (CKWKT) on the growth of human lung carcinoma cell line A549, we performed various biochemical experiments such as the effects of CKWKT on the cell proliferation and viability, the morphological changes, the effects on expression of apoptosis and cell growth-regulatory gene products. Results obtained are as follow; CKWKT treatment declined the cell viability and proliferation of A549 cells in a concentration-dependent manner. The anti-proliferative effect by CKWKT treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. CKWKT treatment induced apoptotic cell death of A549 cells in a concentration-dependent manner, which was associated with inhibition and/or degradation of apoptotic target proteins such poly(ADP-ribose) polymerase, β-catenin and phospholipase C-γ1. Western blot analysis revealed that the levels cyclin-dependent kinase inhibitor p21 expression were induced by CKWKT treatment in A549 cells. Taken together, these findings suggest that CKWKT-induced inhibition of human lung cancer cell proliferation is associated with the induction of apoptotic cell death via regulation of several major growth regulatory gene products and CKWKT may have therapeutic potential in human lung cancer.

• 동의생리병리학회지
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• 제18권4호
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• pp.1102-1106
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• 2004

To investigate the anti-proliferative effects of an aqueous extract of Cordyceps militaris (AECM) on the growth of human lung carcinoma cell line A549, we performed various biochemical experiments such as the effects of AECM on the cell proliferation and viability, the morphological changes, the effects on expression of apoptosis and cell growth-regulatory gene products. Results obtained are as follow; AECM treatment declined the cell viability and proliferation of A549 cells in a concentration-dependent manner. The anti-proliferative effect by AECM treatment in A549 cells was associated with morphological changes such as membrane shrinking and cell rounding up. Taken together, these findings suggest that AECM-induced inhibition of human lung cancer cell proliferation is associated with the induction of apoptotic cell death via regulation of several major growth regulatory gene products, and C. militaris may have therapeutic potential in human lung cancer.

• 한국직업건강간호학회지
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• 제9권2호
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• pp.155-165
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• 2000

This study is to grope for a plan to increase nurse's autonomy by grasping autonomy degree according to nursing delivery system. The subject of this study are 265 nurses who work for 4 general hospitals in Seoul, and 73 of them work in primary nursing delivery system, 99 of them in team nursing delivery system and 93 of them in functional nursing delivery system. Data collection was done through questionaires from Sep. 1, 1997 to Sep. 30, 1997, and autonomy was measured by Professional Nursing Autonomy Scale developed by Schutzonhofer. Data analysis as inspected with $X^2$ test, ANOVA, and t-test, using SPSS program. The results are as follows : 1. When it comes to the autonomy of all the nurses, mean score was 161.99. Which is medium level, and autonomy degree according to nursing delivery system had no significant differences. 2. There was a significant difference in autonomy degree according to inservice education among the subject's work-related characteristics, and there was no significant difference in autonomy distribution in each grade according to general characteristics although older group, married group, and junior college graduates group showed rather higher trends. 3. Considering each item, questions related to direct nursing such as "Vital sign monitoring", "Nursing rounding", "Withhold contraindicated drug", showed high score in autonomy scores, and long-term and indirect nursing behaviors such as "Nursing administration", "Nursing research", "Follow-up care" and "Educational planning".