• Journal of the Korean Data and Information Science Society
• /
• 제22권2호
• /
• pp.287-296
• /
• 2011

36명의 여대생을 대상으로 체 지방 감소효과에 대한 실험을 실시하였다. 이 실험에서 처리는 매일 섭취하는 식사종류 및 양에 대한 식사일지 작성과 카메라 폰으로 찍어 실험관리자에게 전송하여 매주상담을 받는 것이다. 실험관리자는 체 지방 및 관련된 자료를 일주일마다 측정하여 8주간의 반복측정자료를 얻었다. 이 실험자료를 이용하여 혼합모형의 일종인 변량계수모형을 이용하여 추정 및 유의성 검정을 실시한 결과, 유의한 고정인자들은 처리 전체지방 값, 비만지수, 확장기 혈압, 총 콜레스테롤 및 시간이다. 처리 후 시간에 따른 체 지방 감소는 2차 함수의 관계가 성립된다. 변량인자인 개체효과와 개체와 시간과의 교호작용에서 1차 함수의 관계가 존재한다. 처리 후 시간이 지남에 따라 체 지방 량은 점점 감소하였으며, 실험실시 8주 후에는 평균 2.1kg 감소한 효과가 있음을 보여주었다.

• 디지털콘텐츠학회 논문지
• /
• 제16권3호
• /
• pp.355-363
• /
• 2015

본 논문에서는 ATmega기반의 스마트 제어보드를 이용하여, 지형의 경사로에 따라 실시간으로 전동휠체어의 시트를 제어하는 시스템을 제안한다. 스마트 제어보드에는 자이로 및 가속도 센서와 Tilt센서가 포함되어 있으며, 전동휠체어가 다양한 경사로 지형을 지나갈 때 실시간으로 2개의 센서를 이용하여, 지형을 파악할 수 있도록 구성되었다. 본 논문에서는 정확한 지형을 파악할 수 있도록 자이로 센서와 가속도 센서 기반에 상호보안 필터를 적용하여, 전동휠체어가 이동 중에 출력되는 센서 값의 노이즈를 해결하였다. 이를 기반으로 전동휠체어가 이동시 센서 출력 값의 노이즈로 인하여, 시트가 지속적으로 흔들리지 않고 안정적으로 시트 평행을 유지하는 것을 확인할 수 있다. 본 논문에서는 사용자의 편의를 위해 전동휠체어에 익숙하지 않은 사람들이 쉽게 제어할 수 있도록 스마트 폰 기반의 제어 플랫폼을 제공한다. 스마트 폰의 제어플랫폼은 전동휠체어의 현재 상태를 실시간으로 모니터링 할 수 있으며, 욕창 방지와 관련하여, 시트의 기울기를 임의적으로 제어할 수 있도록 도와준다.

• 유체기계공업학회:학술대회논문집
• /
• 유체기계공업학회 2004년도 유체기계 연구개발 발표회 논문집
• /
• pp.140-150
• /
• 2004

In this study, the effect of relative position of the blade for the fixed vane has been investigated on blade surface heat transfer. The experiments were conducted in a low speed stationary annular cascade, and heat transfer of blade was examined for six positions within a pitch. Turbine test section has one stage composed of sixteen guide vanes and blades. The chord length of the tested blade is 150 mm and the mean tip clearance of the blade having flat tip is about $2.5\%$ of the blade chord. For the detailed mass transfer measurements on the blade surfaces, a naphthalene sublimation technique was used. The inlet flow Reynolds number is fixed to $1.5{\times}10^5$. Complex heat transfer characteristics are observed on the blade surface due to various flow characteristics, such as separation bubble, relaminarization, transition to turbulence and leakage vortices. The distributions of velocity and turbulence intensity change significantly with the relative position due to the blockage effect of the blade. This causes the variation of heat transfer patterns on the blade surface. The results show that the flow near the leading edge get highly disturbed and deflected toward the either side of the blade when the blade leading edge is positioned close to the trailing edge of the vane. Therefore, separation bubble disappears on the pressure side and overall heat transfer on the relaminarization region is increased. But, due to reduced tip gap flow at the upstream region, the effect of leakage flow on the upstream region of the blade surface is weakened. Thus, the heat transfer characteristics significantly change with the blade positions.

• 태양에너지
• /
• 제18권3호
• /
• pp.161-167
• /
• 1998

석탄액화시 나무, 리그닌, 흑액 등 바이오매스계 첨가제의 효과를 실험식적 규모의 고온, 고압 반응기에서 고찰하였다. 석탄액화시 리그닌계의 첨가는 석탄의 분해를 돕고, 액체생성물의 질을 높여준다. $400^{\circ}C$에서는 나무를 첨가하게 되면, 액체생성물이 8%정도 증가하지만, 그이상의 온도에서는 기체생성물의 증가로 액체생성물 수율이 줄어든다. 흑액은 액화수율을 증대시키기는 하지만, 그 증가율은 NaOH만을 첨가시킨 경우보다 낮았으며, $OH^-$의 존재 때문에 흑액중의 리그닌이 주는 효과가 그리 크지 않은 것으로 보인다.

• Journal of Ginseng Research
• /
• 제38권1호
• /
• pp.22-27
• /
• 2014

Background: Research has been conducted with regard to the development of methods for improving the pharmaceutical effect of ginseng by conversion of ginsenosides, which are the major active components of ginseng, via high temperature or high-pressure processing. Methods: The present study sought to investigate the anticancer effect of heat-processed American ginseng (HAG) in human gastric cancer AGS cells with a focus on assessing the role of apoptosis as an important mechanistic element in its anticancer actions. Results and Conclusion: HAG significantly reduced the cancer cell proliferation, and the contents of ginsenosides Rb1 and Re were markedly decreased, whereas the peaks of less-polar ginsenosides [20(S,R)-Rg3, Rk1, and Rg5] were newly detected. Based on the activity-guided fractionation of HAG, ginsenoside 20(S)-Rg3 played a key role in inducing apoptosis in human gastric cancer AGS cells, and it was generated mainly from ginsenoside Rb1. Ginsenoside 20(S)-Rg3 induced apoptosis through activation of caspase-3, caspase-8, and caspase-9, as well as regulation of Bcl-2 and Bax expression. Taken together, these findings suggest that heat-processing serves as an increase in the antitumor activity of American ginseng in AGS cells, and ginsenoside 20(S)-Rg3, the active component produced by heat-processing, induces the activation of caspase-3, caspase-8, and caspase-9, which contributes to the apoptotic cell death.

• Journal of Ginseng Research
• /
• 제38권4호
• /
• pp.244-250
• /
• 2014

Background: Panax ginseng has distinct and impressive health benefits, such as improved blood pressure and immune system functioning. Rg3-enriched Korean Red Ginseng (REKRG) isolated from Korean Red Ginseng contains a high percentage of Rg3. Methods: In this study, we examined the effects of REKRG on endothelial cell nitric oxide synthase (eNOS) activation and adhesion molecules in endothelial cells and vascular function in rats. Results: REKRG dose-dependently increased eNOS phosphorylation and nitric oxide (NO) production in endothelial cells. In addition, REKRG markedly inhibited the tumor necrosis factor-${\alpha}$ (TNF-${\alpha}$)-mediated induction of intercellular adhesion molecule (ICAM)-1 and cyclooxygenase (COX)-2 expressions in endothelial cells. REKRG improved endothelium-dependent vasorelaxation in the Wistar-Kyoto (WKY) rat and spontaneously hypertensive rats (SHRs) compared with controls. Furthermore, REKRG treatment for 6 weeks increased serum NO levels and reduced the mean aortic intima-media thickness compared with controls. Conclusion: Taken together, these results suggest that REKRG increased vascular function and improved immune system functioning. Therefore, REKRG is a very useful food for preventing or improving various cardiovascular diseases.

• 한국CDE학회논문집
• /
• 제13권2호
• /
• pp.139-152
• /
• 2008

In order to survive worldwide competition, today's industries are experiencing strong pressure to introduce higher quality products with lower cost and shorter lead-time. Therefore, the role of design in the process of product development is increasing in significance. In this research, two methods for improving the design capability are proposed: construction of design environment and design automation using 3D CAD system. The designers and design process are the core of product design using 3D CAD system. In order to maximize the design performance, construction of the design environment including selection of a suitable system, designer training for best use of the system, establishment of an efficient design process, and stabilization of the environment are required. A method is suggested to construct design environment by systematizing the contents of the projects and consulting experiences carried out for various categories of business such as electronic devices, motorcycles, electricity parts, sanitary wares, injection molds, and die casing molds. Design automation helps reduce tedious and time-consuming jobs, simplify complicated and error-prone modeling and drawing works to shorten the lead time and improve the product quality. To develop a design automation system, understanding the process and the related knowledge on design are very important before implementing the system using API provided by 3D CAD system. In this research, an eight-step procedure is proposed for the development of a design automation system. These eight steps are analysis of needs, determination of specification, verification of specification using 3D CAD system, inspection of related API functions, programming, field test, application in practice, and maintenance. A case study in which five design automation systems in the design of turbine generators using the proposed method is introduced in detail. These systems play important roles in the generation of various output items including 3D models, drafts, material information, and NC data. The case study shows how effectively the design time is reduced and the quality improved using those systems.

• 한국수산과학회지
• /
• 제33권5호
• /
• pp.399-402
• /
• 2000

일반적인 수산물 통조림의 내용물 속에는 물, 기름 및 조미액즙 등 packing medium이 들어있다. 본 연구에서는 새우, 꽁치 및 굴을 원료로 건조 및 조미 후 packing medium이 없는 새로운 형태의 조미통조림을 제조하고 이들 제품의 진공도별 (15, 30, 45 및 60cmHg) 열침투 특성을 조사할 목적으로 본 연구를 수행하였다. 진공도별 제품의 열침투 속도는 진공도가 높을수록 빠르게 나타났으며 동일시간 살균했을 때 진공도가 높을수록 Fo치가 높게 나타났다. 한편 상법으로 제조된 water pack과 본 시험에서 제조한 조미통조림과의 열침투 속도를 비교했을 때 새우와 꽁치 조미통조림의 경우는 진공도 15cmHg 이상에서는 열침투 속도가 water pack 제품보다는 빠르게 나타났고 굴 제품의 경우는 water pack 제품이 30cmHg 이상에서 열침투 속도가 빠르게 나타났다. 따라서 packing medium이 없는 조미 통조림의 경우 진공도 30cmHg 이상이 되면 기존의 water pack 제품보다 열침투 속도가 빠르다는 사실이 관찰되었다.

• 치위생과학회지
• /
• 제18권3호
• /
• pp.147-154
• /
• 2018

This study aimed to evaluate the antimicrobial effects of Acanthopanax sessiliflorum fruit (ASF; Ogaza) extracts on Streptococcus mutans and Streptococcus sobrinus, which are agents that cause dental caries, and on Streptococcus mitis and Streptococcus salivarius, the microbial flora of the oral cavity. The ASF extracts obtained using 70% ethanol were fractionated in the order of ethyl acetate and n-Butanol, concentrated under reduced pressure, and lyophilized to give powdery solvent extracts. The antimicrobial activity of ASF extracts from each solvent was examined using the disk diffusion method. As a result, only those extracts obtained using an ethyl acetate solvent showed antimicrobial activity. These extracts were selected, and the minimum inhibitory concentration was measured by disk diffusion method at various extract concentrations. Results showed a minimum inhibitory concentration of 32 mg/ml. The viable cell count was measured to confirm the minimum bactericidal concentration. Results showed a minimum bactericidal concentration of 64 mg/ml. In the cytotoxicity test using normal human dermal fibroblast cells, the absorbance value of the test group was similar to that of the control group at 0.64, 1.28, and 6.4 mg/ml. The bacteria and their colonies were examined using a scanning electron microscope. Boundaries between the antimicrobial activity region and non-antimicrobial activity region were observed around the paper disk, which was immersed in the extract with 32 mg/ml concentration. Bacterial colonization was not observed in the area with antimicrobial activity. This finding suggests that ASF extracts can inhibit the growth of some microorganisms in the oral cavity, in addition to the effects of these extracts known to date. In particular, ASF extracts may be used as a preparation for preventing dental caries by adding the extract to the toothpaste or oral mouthwash.

• 상하수도학회지
• /
• 제21권1호
• /
• pp.123-130
• /
• 2007

The effects of hydrogen peroxide treatment on the reduction of waterworks sludge were investigated in this study. Sludge treated by peroxidation $H_2O_2$ oxidation) was dewatered using a pressure filter at 3atm. It was observed that $H_2O_2$ treatment at the acidic condition significantly reduce both cake water content and specific resistance to filtration (SRF), indicating the enhancement of dewaterability and filterability. The filterability by hydrogen peroxide treatment at pH 3.5 was better than acidic treatment and became comparable with polymer conditioning. The sludge filterability evaluated by SRF was optimal at a dose 2ml $H_2O_2$/sludge($0.02g\;H_2O_2/gTS$) after adjusting of pH to 3.5. The $H_2O_2$ oxidation at pH 3.5 also produced even more dewatered cake when compared with polymer conditioning. The reduction rate of sludge mass at an optimal condition showed 34% compared with untreated sludge. The effects of peroxidation on sludge properties including zeta potential, bound water and particle size were also evaluated. Peroxidation at the acidic condition reduced both bound water and zeta potential. By $H_2O_2$ combined with sulfuric acid leached iron caused Fenton's reaction, which showed a potential to significantly reduce the amount of solids mass and to produce more compact cake with higher filterability.