• 한국농림기상학회지
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• 제11권1호
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• pp.3-12
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• 2009

수목의 오존 내성을 단기 노출 후 나타난 생리적 피해와 생화학적 반응들의 표준화 지수로 결정하였다. 모감주나무, 벽오동, 때죽나무, 물푸레나무, 백당나무를 150ppb 오존 노출 시킨 후, 광합성 특성, MDA 함량 및 항산화효소의 활성을 측정하여 피해지수는 광합성 파라미터와 MDA 함량 변화를 이용하여 계산하였으며, 내성지수는 항산화효소의 활성 변화를 측정하여 산출하였다. 순양자수율, 탄소고정효율, 광호흡속도는 오존 노출시간에 따라 감소하여, 스트레스 평가지표로 적당한 것으로 판단되었다. 항산화효소의 활성은 수종, 노출시간 및 효소 종류에 따라 다양한 결과를 보여 주었다. 모감주나무 SOD 활성은 오존 노출시간에 따라 증가하였고, 물푸레나무의 SOD 활성은 오존 노출 6 시간 후에 증가하였으며, 벽오동의 CAT 활성은 무처리보다 낮았다. 표준화 지수를 기초로 한 5개 수목의 오존 내성은 두 내성 수종(물푸레나무>모감주나무)과 세 민감성 수종(때죽나무>벽오동>백당나무)으로 구분되었다.

• 에너지공학
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• 제21권1호
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• pp.18-25
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• 2012

굴뚝내 수직 원형관의 자연대류에서 굴뚝의 입구길이, 출구길이, 그리고 굴뚝의 직경에 따른 열전달 변화를 실험적으로 연구하였다. 상사성을 이용하여 열전달 실험 대신 물질전달 실험을 수행하였다. 직경 0.054 m, 높이 0.03, 0.07, 0.10 m의 원형관에 대하여 굴뚝의 직경을 0.06 m에서 0.14 m까지, 높이를 0.30 m에서 1.10 m까지 변화시켰다. 이는 Pr 수 2,094, $Ra_L$ 수 $4.55{\times}10^9$, $5.79{\times}10^{10}$, 그리고 $1.69{\times}10^{11}$에 해당한다. 굴뚝이 없을 때, 수직 원형관의 열전달은 Le Ferve의 수직평판에 대한 층류 자연대류 상관식과 일치하였다. 출구길이를 증가시키며 실험한 결과, 열전달은 증가하다가 특정 출구길이 이상에서는 일정해 졌다. 반면, 입구길이를 증가시킬 때는 열전달은 감소하다가 특정 입구길이 이상에서는 일정해졌다. 굴뚝효과로 증가된 열전달은 굴뚝의 직경을 증가시킬수록 감소하다가 굴뚝이 없을 때와 같아졌다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2005년도 춘계학술대회 논문집
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• pp.1206-1209
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• 2005

In recent, injection molding process for features in sub-micron scale is under active development as patterning nano-scale features, which can provide the master or stamp for molding, and becomes available around the world. Injection molding has been one of the most efficient processes for mass production of the plastic product, and this process is already applied to nano-technology products successfully such as optical storage media like DVD or BD which is a large area plastic thin substrate with nano-scale features on its surface. Bio chip for like DNA sequencing may be another application of this plastic substrate. The DNA can be sequenced using order of 100 nm pore structure when making the DNA flow through the pore structure. Agarose gel and silicon based chip have been used to sequence the DNA, but injection molded plastic chip may have benefit in terms of cost. This plastic DNA sequencing chip has plenty of pillars in order of 100 nm in diameter on the substrate. When the usual features in case of DVD or BD have very low aspect ratio, even less than 0.5, but the DNA chip will have relatively high aspect ratio of about 2. It is not easy to injection mold the large area thin substrate with sub-micron features on its surface due to the characteristics of the molding process and it becomes much more difficult when the aspect ratio of the features becomes high. We investigated the effect of the molding parameters for injection molding with high aspect ratio nano-scale features and injection molded some plastic DNA sequencing chips. We also fabricated PR masters and Ni stamps of the DNA chip to be used for molding

• Journal of Electrical Engineering and Technology
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• 제13권6호
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• pp.2545-2552
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• 2018

$SF_6$ has been widely used in high voltage power equipment, such as gas insulated switchgear (GIS) and gas insulated transmission line (GIL), because of its excellent insulation and arc extinguishing performance. However, $SF_6$ faces two environmental problems: greenhouse effect and high liquefaction temperature. Therefore, to find the $SF_6$ substitute gases has become a research hotspot in recent years. In this paper, the liquefaction characteristics of $SF_6$ substitute gases were studied. Peng-Robinson equation of state with the van der Waals mixing rule (PR-vdW model) was used to calculate the dew point temperature of the binary gas mixtures, with $SF_6$, $C_3F_8$, $c-C_4F_8$, $CF_3I$ or $C_4F_7N$ as the insulating gas and $N_2$ or $CO_2$ as the buffer gas. The sequence of the dew point temperatures of the binary gas mixtures under the same pressure and composition ratio was obtained. $SF_6/N_2$ < $SF_6/CO_2$ < $C_3F_8/N_2$ < $C_3F_8/CO_2$ < $CF_3I/N_2$ < $CF_3I/CO_2$ < $c-C_4F_8/N_2$ < $C_4F_7N/N_2$ < $c-C_4F_8/CO_2$ < $C_4F_7N/CO_2$. $SF_6/N_2$ gas mixture showed the best temperature adaptability and $C_4F_7N/CO_2$ gas mixture showed the worst temperature adaptability. Furthermore, the dew point temperatures of the $SF_6$ substitute gases at different pressures and the upper limits of the insulating gas mole fraction at $-30^{\circ}C$, $-20^{\circ}C$ and $-10^{\circ}C$ were obtained. The results would supply sufficient data support for GIS/GIL operators and researchers.

• Radiation Oncology Journal
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• 제12권2호
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• pp.191-199
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• 1994

Purpose : This study was undertaken to show the clinical results of combined radiotherapy and hyperthermia in primary hepatoma Materials and Methods : Between December 1989 and March 1993, 50 patients with hepatomas were treated by combined radiotherapy and hyperthermia. Among them, we analyzed retrospectively 33 patients who received the complete course of treatment. The ages of the patients ranged from 36 to 75(mean age: 55.5 years). Twenty-six patients ($78.8\%$) were men, and 7 ($21.2\%$ were women. According to Child's classification, nine patients ($27.3{\%}$) were A group, 9 ($27.3\%$) were B group, 15 ($45.4\%$) were C group. Radiation therapy was done by a 6 MV and 15 MV linear accelerator. Patients were treated with daily fractions of 150-180 cCy to doses of 2550 cGy -4950 cGy (median : 3000 cGy). Local hyperthermia was done by 8 MHZ RF capacitive heating device (Cancermia. Green Cross Co., Korea), 50-60 min/session, 1-2 sessions/wk, and 8.5 sessions (median number)/patient. We analyzed the prognostic factors including age, sex, tumor type, Child's classification, $\alpha$-fetoprotein, liver cirrhosis, ascites, portal vein invasion, esophageal varix, number of hyperthermia, chemotherapy, total bilirubin level, Karnofsky perfomance status. Results : The overall 1-year survival was $24.2\%$, with a mean survival of 10months. Of 33 patients, tumor regression (PR+MR) was seen in $30.4\%$, no response was seen in $52.2\%,\;17.4\%$ patient was progressed. In patients who had tumor regression, the overall 1-year survival was $42.1\%$ with a mean survival of 14 months. Factors influencing the survival were sex (p=0.05), tumor type (p=0.0248), Child's classification (p=0.0001), liver cirrhosis (p=0.0108), ascites (p=0.0009), and Karnofsky perfomance status (p=0.0028). Complications developed in 28 patients, including 18 hot pain,5 fat necrosis, 3 transient fever, 2 nausea and vomiting. Conclusion : In this study, the results suggests that combined radiotherauy and hyperthermia may improve the survival rate of hepatoma.

• 한국산학기술학회논문지
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• 제18권3호
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• pp.270-276
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• 2017

본 연구에서는 '비교 광고'가 성립되기 위해서는 법률적 차원의 조건을 충족시켜야 하며 그렇지 않을 경우에는 '부당한 비교 광고'가 될 수 있음에도 불구하고 이에 대해 고려하지 않은 기존의 비교 광고의 효과 연구들에 대해 문제점을 제시하였다. 이러한 맥락에서 본 연구는 '부당하게 비교하는 광고'에 대한 현행 규제 법률인 '표시 광고의 공정화에 관한 법률'에 근거한 '비교 표시 광고에 관한 심사 지침' 중 '부당하게 비교하는 표시 광고'의 규정 내용을 검토하여 그 법률적 정의를 분명히 하였다. 그리고 '부당하게 비교하는 광고'에 대한 과거의 규제 법률인 '독점규제 및 공정거래에 관한 법률'에서는 비교 광고를 금지하였었다는 주장의 사실 여부를 확인하고 또한 현행 및 과거의 규정 간에는 어떠한 차이가 있는지를 알아보기 위해 과거의 규제 법률이 적용된 심결 사례 354건을 질적으로 내용 분석하였다. 그 결과, 부당하게 비교하는 표시 광고에 대한 과거 및 현재의 두 법률상의 판단 기준은 동일한 것으로 나타났다. 결론적으로, 본 연구는 국내에서의 비교 광고 금지 여부에 대한 논쟁에 대해 비교 광고는 과거의 법률에서도 금지된 적이 없었으며 또한 과거 및 현행 법률상의 비교 광고의 의미와 부당한 비교 광고의 판단 기준에는 변화가 없었다는 사실을 실증적으로 밝혔다는 점에서 의의를 지닌다.

• Biomolecules & Therapeutics
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• 제22권4호
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• pp.347-354
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• 2014

Larrea nitida is a plant that belongs to the Zygophyllaceae family and is widely used in South America to treat inflammatory diseases, tumors and menstrual pain. However, its pharmacological activity remains unclear. In this study we evaluated the property of selective estrogen receptor modulator (SERM) of Larrea nitida extracts (LNE) as a phytoestrogen that can mimic, modulate or disrupt the actions of endogenous estrogens, depending on the tissue and relative amount of other SERMs. To investigate the property of SERM of LNE, we performed MCF-7 cell proliferation assays, estrogen response element (ERE)-luciferase reporter gene assay, human estrogen receptor (hER) binding assays and in vivo uterotrophic assay. To gain insight into the active principles, we performed a bioassay-guided analysis of LNE employing solvents of various polarities and using classical column chromatography, which yielded 16 fractions (LNs). LNE showed high binding affinities for $hER{\alpha}$ and $hER{\beta}$ with $IC_{50}$ values of $1.20{\times}10^{-7}$ g/ml and $1.00{\times}10^{-7}$ g/ml, respectively. LNE induced $17{\beta}$-estradiol (E2)-induced MCF-7 cell proliferation, however, it reduced the proliferation in the presence of E2. Furthermore, LNE had an atrophic effect in the uterus of immature rats through reducing the expression level of progesterone receptor (PR) proteins. LN08 and LN10 had more potent affinities for binding on $hER{\alpha}$ and ${\beta}$ than other fractions. Our results indicate that LNE had higher binding affinities for $hER{\beta}$ than $hER{\alpha}$, and showed SERM properties in MCF-7 breast cancer cells and the rat uterus. LNE may be useful for the treatment of estrogen-related conditions, such as female cancers and menopause.

• 대한치과마취과학회지
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• 제13권1호
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• pp.1-7
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• 2013

Background: Intravenous sedation is effective for dental patients who are anxious. Recently, target-controlled infusion (TCI) has begun to be used widely to administer and titrate propofol and remifentanil during sedation. To investigate the effect and safety of the pharmacologic agents used in anesthetic department, we performed a retrospective study. Methods: Retrospective study of a series of dental procedure under intravenous sedation performed in department of anesthesiology in Dental Hospital of Dankook University was carried out with propofol or propofol/remifentanil between January and August 2011 and January and April 2012. All patients received oxygen by nasal cannula. The average propofol and remifentanil target was 0.5 ${\mu}g/ml$ and 1.0 ng/ml, respectively using a TCI pump. The average peripheral oxygen saturation ($SpO_2$), heart rate, blood pressure, respiratory rate, nasal end-tidal $CO_2$ were recorded at 5-10 minute intervals. The age, gender, weight, procedure and sedation time, type of procedure were also recorded. Results: We included 22 cases of 19 adults (group A) and 6 cases of children (group B). In group A, 4 patients received propofol (group A-P), and 15 patients received propofol with remifentanil (group A-PR). In group B, 6 patients received propofol only. The mean age of group A was 41.1 years old and that of group B was 9.5 years old. No clinically significant complications were noted. There were no case of de-saturation <90%. The median respiratory rate was 13.1 (range 6 to 36) in group A and 19 (range 13 to 25) in group B. The median end tidal $CO_2$ was 36.7 mmHg(range 8 mmHg to 56 mmHg) in group A and 41.7 mmHg (range 30 mmHg to 53 mmHg) in group B. Conclusions: Based on our results, dental sedation using propofol/remifentanil in adult and propofol in children with TCI pump seems to appear as a safe and effective procedure while performing dental procedure.

• Asian Pacific Journal of Cancer Prevention
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• 제14권8호
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• pp.4583-4589
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• 2013

Objective: This study aimed to investigate the effect of multimodality treatment of advanced paediatric hepatoblastoma (HB) and the factors affecting prognosis. Methods: A total of 35 children underwent multimodality treatments consisting of chemotherapy, surgery, interventional therapy, and autologous peripheral blood stem cell transplantation. The patients were followed up every month. Results: Serum AFP levels in 33 out of 35 patients in this study were significantly increased (P = 0.0002). According to the statistical scatter plot, the values of serum AFP on the 25th, 50th, and 75th percentages were 1,210, 1,210 and 28,318 ng/dl, respectively. Of the 35 cases, 21 were stage IV. 18 cases were treated with systemic chemotherapy before surgery, and 3 cases with locally interventional chemotherapy before surgery. Statistical analysis showed that the preferred interventional treatment affected prognosis, and that there was a statistically significant difference (P = 0.024). Some 33 patients completed the follow-up, of which 17 were in complete remission (CR), 5 were in partial remission (PR), 1 became disease progressive (DP), and 10 died. The remission and overall survival rates were 66.7% (22/33) and 69.7% (23/33), respectively. Patients with the mixed HB phenotypes had worse prognoses than the epithelial phenotype (P < 0.001), and patients in stage IV had a lower survival rate than those in stage III (P < 0.001). Conclusion: Multimodality treatment can effectively improve remission rate and prolong the survival of children with advanced HB. In addition, alpha-fetoprotein (AFP), a tumor marker of liver malignant tumors, HB pathological classification, and staging are highly useful in predicting prognosis.

• 한국언론정보학보
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• 제33권
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• pp.169-191
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• 2006

이 연구에서는 방송광고 판매제도 개선에서의 경쟁도입이 각 매체의 광고수입에 미치는 영향을 분석하고, 그에 기초해 바람직한 제도개선을 위한 제도적 장치를 추론코자 하였다. 경쟁도입은 방송광고 요금인상과 방송광고비 증가를 초래하며, 이로 인한 사회적 부작용을 제어할 장치가 없다면 언론매체의 다양성과 균형발전이 훼손되고, 여론의 독과점이 촉진되는 부작용을 피할 수 없다. 따라서 방송광고판매에 경쟁체제를 도입하되, 방송법이 규정한 방송의 제작편성과 광고영업의 제도적 분리를 실질적으로 담보할 수 있는 제도적 장치와, 방송광고 요금의 인상과 그로 인한 방송광고비의 증가를 사회적으로 조절할 수 있는 제도적 장치를 갖추는 것이 필요하다. 그 제도적 장치들은 다음과 같은 다섯 가지이다. 첫째, 방송광고 거래의 투명성과 공정성을 유지하는 것이다. 둘째, 방송사의 직접적 광고영업을 금지하고 더 나아가 직접영업 효과를 차단하는 것이다. 셋째, 공영방송이 공적서비스에 전념할 수 있도록 관련 정책을 정비 개선하는 것이다. 넷째, 광고시장에 대한 사회적 개입수단을 운용하는 것이다. 다섯째, 지역방송과 종교방송 등이 공적인 기본 기능을 수행할 수 있도록 최소한의 재원을 적절히 보장하는 것이다.