• Journal of the korean academy of Pediatric Dentistry
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• v.42 no.3
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• pp.233-241
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• 2015

The aim of this study was to determine the bite force and lip closing force in preschool children and to analyze the correlation between these forces by age, height and weight, respectively. Data were obtained from 98 children (56 males, 42 females) ranging from 3 to 6 years of age. The magnitude of the bite force was measured bilaterally corresponding with the 2nd primary molars using a bite force gauge, $GM10^{(R)}$ (Nagano Keiki) and the force of lip closure was measured using LIP DE $CUM^{(R)}$ (Cosmo Instruments). The averages of bite force for boys and girls were 217.69 N and 205.05 N, respectively. The relationship between bite force with age, height, and weight present significant positive correlation (p < 0.001, p < 0.001, and p < 0.001, respectively). The averages of lip closing force for boys and girls were 4.81 N and 4.07 N respectively. The relationship between lip closing force with age, height, and weight present significant positive correlation (p < 0.001, p < 0.001, and p < 0.001, respectively). No significant differences were observed between boys and girls (p > 0.05) in both forces. A significant correlation was observed between lip closing force and bite force (p = 0.002).

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1133-1138
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• 2004

This study has been carried out to investigate the effect of the administration of Rhemanniae Radix extract (5.0 mL/kg/day, RR group) on the hyperglycemic mice (HM group) induced with streptozotocin (STZ). In blood glucose level, RR group showed a significant decrease compared with HM group. The result of glucose tolerance test was more favorable in RR than HM group. A lot of insulin-positive cells and insulin-like growth factor-II positive materials were observed in RR group. A number of apoptotic particles were observed in the HM group, but several apoptotic nuclei were found in RR group. Pancreatic islets of HM group were destructed by the administration of STZ, but islets were recovered from damage in the RR group. These results suggest that administration of Rhemanniae Radix extract to the hyperglycemic mice prevent from the damage induced by STZ.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.74.1-74.1
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• 2011

탄소나노튜브는 높은 전기 전도성과 열 전도성을 가지며, 이러한 특성 때문에 21세기를 주도해 나갈 수 있는 차세대 첨단 소재로서 각광을 받고 있다. 또한 최근에는 나노공학기술의 발달로 인하여 획기적으로 높은 열전도도를 나타내는 다중벽 탄소나노튜브(Multi-walled Carbon Nanotubes, MWCNTs)의 대량 생산이 가능하게 되면서 다중벽 탄소나노튜브의 높은 열전도도 특성을 이용하여 탄소나노튜브를 기본 유체 및 기능성 유체에 안정하게 분산 시킨 후 이를 이용하고자 하는 연구가 활발히 진행되고 있으며, 탄소나노튜브를 유체에 안정하게 분산시키기 위한 방법으로는 기계적 분산법, 물리적 흡착에 의한 분산법, 화학적 개질에 의한 분산법이 있다. 따라서 본 연구에서는 이들 분산 방법과 탄소나노튜브 입자의 물성치에 따른 나노유체의 특성을 알아보기 위하여 나노유체의 열전도도와 점도 특성을 비교 분석하였다. 모든 물성치는 같지만 탄소나노튜브의 길이만 다른 두 종류의 다중벽 탄소나노튜브에 각각 계면 활성제(Sodium Dodecyl Sulfate, SDS) 100 wt%와 고분자 화합물(Polyvinyl Pyrrolidone, PVP) 300 wt%를 첨가하여 나노유체를 제조하였으며, 산화처리 된 다중벽 탄소나노튜브(Oxidized Multi-Walled Carbon Nanotubes, OMWCNTs)를 증류수에 초음파 분산하여 산화나노유체를 제조하였다. 나노유체의 열전도도는 전기 전도성 유체의 비정상 열선법(Transient Hot-wire Method)을 이용하여 측정하였고, 나노유체의 점도는 회전형 디지털 점도계를 이용하여 측정하였다. 실험 결과, 상온에서 동일 혼합비의 나노유체를 비교했을 때, 산화나노유체가 SDS 100 wt%, PVP 300 wt%를 혼합한 다른 나노유체보다 높은 열전도도 특성을 보였으며 점도 특성 또한 가장 낮은 것으로 측정되었다. 특히 상온에서 0.1vol%의 산화 CM-100 나노유체는 증류수보다 열전도도가 8.34%가 증가하였고, $10^{\circ}C$의 저온에서는 상온에서 증류수와 비교하여 측정된 열전도도 값보다 0.36%가 감소한 7.98%가 증가함을 보였다. 본 연구를 통하여 얻어진 결과는 높은 열전도도를 필요로 하는 열교환기의 작동유체나 기타 활용 분야에 대한 기초 자료로써 유용한 정보를 제공할 것이라 판단된다.

• The korean journal of orthodontics
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• v.26 no.4
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• pp.373-387
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• 1996

The purpose of this study was to evaluate the growth pattern of nasopharyx and adenoid and to obtain useful measurements for evaluating the fuction of the nasal breathing. The biennial serial cephalometric radiographs of 33 samples(19 male, 14 female) with normal occlusion from 8.5 years to 18.5 years of age were used in this study. The distances, areas and ratios on nasopharynx and adenoid were measured and analyzed in each age and sex. The results of this study might be summarized as follows ; 1. The mean value and standard deviation of each measurement was obtained in each age and sex. 2. The nasopharyngeal height and the nasopharyngeal depth increased significantly by 14.5 years of age in male and 12.5 years of age in female(p<0,05), 3. The relative nasal airway area showed the minimal value at 8.5 years of age and showed significant increase from 10.5 years to 12.5 years of age in male and from 12.5 years to 14,5 years of age in female(p<0.05). 4. In the correlation analysis between the measurements on the nasal airway and the measurement of relative nasal airway area, the measurements of Ad2-PNS, Ad2-PNS/Ho'-PNS and Upper pharynx appeared singnificant correlation with the measurement of relative nasal airway area(p<0.01).

• Journal of the Korean Society of Radiology
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• v.5 no.1
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• pp.37-49
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• 2011

To examine the possible changes in the SNRs, CNRs, and ADC values for lumbar spines with metastasis based on the DW images before and after contrast agent injection taken from metastatic spinal cancer patients using a 1.5 T MR machine. The quantitative analysis revealed that in case of spinal cancer subjects, both SNRs and CNRs at all of those assessed locations significantly increased on the DWI after contrast agent injection compared to before, while on the ADC map images, SNRs significantly decreased. On the other hand, significantly decreased ADC values at all the assessed locations were found on the ADC map images. With reference to the normal group, significantly increased SNRs were found at all of the assessed locations on the DWI image after injection compared to before, while significantly decreased SNRs were found on the ADC map images. Also, significantly decreased ADC values at all the assessed locations were found on the ADC map images. For the qualitative analysis, after contrast agent injection, significantly increased signal intensities were found at the locations with spinal cancer on the DWI. In contrast, significantly decreased signal intensities were found on the ADC map images. The implication from the results showing that SNR and CNR significantly increased while ADC value significantly decreased at, above, and below the location of metastatic spinal cancer on DWI after contrast agent injection is that DWI obtained after contrast agent injection can be made available for wider application to vertebral disorders.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.5
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• pp.12-18
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• 2006

A new steady approach has been developed to predict the transonic buffet onset of a high speed aircraft. In this paper, the flow is assumed to be steady for the buffet onset. The present study involves the analysis of a distinct change in the variation of various static aerodynamic parameters. These distinct changes indicates the onset of transonic buffet. Among the various aerodynamic parameters considered in this study, the variation in the center of pressure has shown to provide a clearest indicator of transonic buffet onset. This new steady approach can be applied to predict the transonic buffet onset for airfoils with shock induced separation bubble and for large swept wings with small aspect ratios. Good agreements have been obtained compared with unsteady wind tunnel buffet test data. Based on the results obtained the new steady approach, it can be newly suggested that the distinct slope changes of the center of pressure curve can be used as an indicator of buffet onset for the steady experimental method on a full aircraft configuration.

• Journal of Food Hygiene and Safety
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• v.22 no.3
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• pp.213-217
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• 2007

LPS induces the synthesis of several inflammatory cytokine, chemokine, NO and inflammation in the liver of rats. The purpose of this study was to investigate the preventive effects of Rubus coreanum Miquel (RCM) In lipid metabolism. RCM of 100 mg/kg concentration was intraperitoneally administered into rats at dose of 1.5ml/kg for 20 days. On the day 21, 1.5ml/kg of LPS was injected 4 hours before anesthetization. We examined the lipid-related functions by measuring the levels of triglyceride (TG), total cholesterol (TC), total lipid (TL), high-density lipoprotein cholesterol (HDL-C) in serum and malondialdehyde(MDA) in liver tissue. The results showed that LPS treatment increased the values of TG, TC, TL and MDA, decreasing that of HDL-C. But RCM pretreatment decreased the high values of TG, TC, TL and MDA to the low values and increased the low value of HDL-C to the high value. These results suggested that RCM could be used as the potential candidate for the lipid metabolism natural supplement.

• Journal of Korean Orthopaedic Sports Medicine
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• v.5 no.1
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• pp.41-44
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• 2006

Purpose: To evaluate the short-term results of arthroscopic ACL reconstruction using fresh frozen Achilles allograft Materials & Methods: From March 2002 to March 2004, arthroscopic ACL reconstructions using fresh frozen Achilles allograft were performed in 25 knees of 25 patients. The average age at operation was 30.1 years (range, 18-50 years) and the average follow-up was 17 months (range, 12 to 27months). Preoperative and follow-up clinical results were evaluated using the Lysholm knee score, IKDC knee rating system, physical examination and KT-2000 arthrometer. Results: The Lachman test was positive in 25 patients preoperatively and 18 patients(72%) had negative results at latest follow-up. The average side-to-side differences of anterior tibial translation using KT-2000 arthrometer under loading of 301b were improved from $7.9{\pm}2.4mm\;to\;2.6{\pm}1.6mm$. The average Lysholm score was improved from $61.1{\pm}13.9\;to\;93.5{\pm}5.3$ points. The IKDC grade was abnormal(C) or severely abnormal(D) in 25 cases preoperatively They improved 22(88%) of normal(A) or nearly normal(B) and 3(12%) of abnormal. Conclusion: Short term results of ACL reconstruction using Achilles allograft was acceptable. Achilles allograft can be a reasonable graft alternative to autograft for ACL reconstruction.

• Korean Journal of Animal Reproduction
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• v.26 no.2
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• pp.193-199
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• 2002

This study was conducted to investigate the optimal physiologic mating time in Hanwoo for protection to decrease of reproductivity and improvement of production of offspring. We observed 32 cows that were devide into 4 parts of treatment : T1(12 months of age and 0.5kg daily gain), T2(12 months of age and 0.8kg daily gain), T3(15 months of age and 0.5kg daily gain) and T4(18 months and 0.5kg daily gain). The first heat of treated cows was 263.3$\pm$6.4 days and average weight was 181.1$\pm$11.3kg. It was revealed the conception rates of first insemination were 25%(T1), 75%(T4) and number of insemination of T3 and T4(both 1.5) was lower than T1 and T2(2.3 and 2.4). In return of estrus after heifer's first parturition, they(T1, T2, T3 and T4) showed 66.2 days, 76.7 days, 62.4 days and 68.5 days respectively and the average was 65.7 days. Plasma progesterone(P4) concentration was nearly the same during the observation periods of treated cows and P4 was released just after 12 months. Only 5 cows (15.6%) in 32 were showed normal estrus cycle and ovulation before 12 months. Before and after parturition, P4 concentration was decreased fastly and then there was no detection of P4 from after parturition to 40 days after milking. P4 would be released again on 45 day after parturition. The results were summarized as that the optimal mating time of Hanwoo heifers was decided by the 14 months of age, 110 cm height and 265kg weight.

• Analytical Science and Technology
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• v.24 no.2
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• pp.85-93
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• 2011

To protect the steel structure in a high story buildings from fire, the sprayed fire-resistive materials are applied during the construction. Current standard methods to check the quality of sprayed fire-resistive materials are real fire test in lab, which take a long time (several weeks) and expensive. In this study, a simple analytical method to check the quality of sprayed fire-resistive materials is developed using Near Infrared Spectroscopy (NIR). Total 9 kinds of sprayed fire-resisted materials and 3 kinds of normal sprayed material sets were used for the analysis. Each set of materials was 50 to 100 samples. Samples are grinded and make a fine powder. The spectral data acquisition was carried out using FT-NIR spectrometer with a integrating sphere. NIR methods successfully identify the sprayed fire resistive materials by a principle component analysis (PCA) after a vector normalization (SNV) pretreatment.