• 대한치과보철학회지
• /
• 제52권3호
• /
• pp.233-238
• /
• 2014

목적: 상, 하악골 혹은 치조골의 골밀도에 대한 지표를 나타낼 수 있는 방법의 개발은 치주질환의 관리, 치과 임플란트 치료 및 전신 골다공증의 진단 등에 유용하게 사용될 수 있다. 대상 및 방법: 팬텀을 포함하는 평행법 촬영기구(XCP)를 이용해 골밀도를 측정하고 이를 정량적 전산화 단층촬영 영상의 값과 비교하여 구강 내 치근단 방사선 영상을 이용한 골밀도 측정의 유용성을 평가하였다. 결과: 실험 결과 치조골의 골밀도에서 두 방법은 0.92 (P<.001)로 높은 상관관계를 보였고, 해면골에 국한된 골밀도는 0.73 (P<.001)으로 비교적 높은 유의한 상관관계를 보였다. 결론: 구강 내 치근단 방사선 영상을 통한 치조골 골밀도 측정의 가능성을 제시하였다.

• 대한의용생체공학회:학술대회논문집
• /
• 대한의용생체공학회 1998년도 추계학술대회
• /
• pp.169-170
• /
• 1998

In this study, regional variation in vertebral bone density due to osteoporosis were investigated using a method that employs images from QCT. QCT images(1mm thick slices) of the first lumbar vertebra from a normal person (23/M, BMD=139.8mg/ml) and from an osteoporotic patient (54/F, BMD=82.0mg/ml) were obtained. Uniform settings (140kVp, 204mA) were used and images of 300 Hounsfield Unit or greater were selectied to filler out soft tissue interference. To assess the regional variation of the area fraction the vertebral body was divided into 3 layers and each layer contained 9 regions. Area faction was calculated based on image analysis data. Our results showed that the area fraction at the middle of the vertebra was quite lower than the endplate and peripheral regions, but the area fraction values from the osteoporotic patient were uniform throughout the entire height of the vertebral body, which indicates the significant drop of BMD had occurred near both end-plates due to the osteoporosis, especially at the peripheral regions. Our results suggest the susceptability of the vertebrae to compression fracture types in osteoporotic spine.

• International Journal of Oral Biology
• /
• 제32권4호
• /
• pp.143-151
• /
• 2007

This study was conducted to investigate the preventing effects of OPB (Rehmannia glutinosa Libosch and Eleutherococcus senticosus Max extracts) and combined OPB/Calcium therapy on bone loss in ovariectomized rats. Sixty Sprague Dawley rats of 12-week-old were divided into eight groups: OVX (ovariectomized), OPBL (OPB 50 mg/kg), OPBM (OPB100 mg/kg), OPBH (OPB 200 mg/kg), OPBL/CAL(OPBL+CAL), OPBM/CAL (OPBM+CAL), OPBH/CAL (OPBH+CAL) and CAL (Calcium citrate 88.33 mg/kg+1$\alpha$, 25-dihydroxy-vitamin $D_3$ 33.33 IU/kg). Bone mineral density (BMD), bone mineral content (BMC), bone strength indices and cortical thickness were analyzed by peripheral quantitative computerized tomography (pQCT). pQCT scanning showed that OVX induced a significant decrease in trabecular bone mineral density and bone mineral content in the proximal tibia $(-36.4\pm2.4%,\;-21.8\pm12.7%)$. These decreases were significantly prevented by the administration of OPBM and OPBM/CAL. Cortical BMD and BMC of tibia were slightly enhanced by OPB and OPB/CAL. However there was no significant difference between OVX and OPB, OPB/CAL treated group. Bone strength indices and cortical thickness were not significantly different. Our results suggest that OPB and combined OPB/Calcium therapy are effective in preventing the development of bone loss induced by ovariectomy in rats.

• Bulletin of the Korean Chemical Society
• /
• 제31권10호
• /
• pp.2841-2848
• /
• 2010

Quasiclassical trajectory (QCT) method has been used to investigate stereodynamics information of the reaction $O(^1D)+H_2{\rightarrow}\;OH$+H on the DK (Dobbyn and Knowles) potential energy surface (PES) at a collision energy of 23.06 kcal/mol, with the initial quantum state of reactant $H_2$ being set for v = 0 (vibration quantum number) and j = 0-5 (rotation quantum number). The PDDCSs (polarization dependent differential cross sections) and the distributions of P($\theta_r$), P($\phi_r$), P($\theta_r$, $\phi_r$) have been presented in this work. The results demonstrate that the products are both forward and backward scattered. As j increases, the backward scattering becomes weaker while the forward scattering becomes slightly stronger. The distribution of P($\theta_r$) indicates that the product rotational angular momentum j' tends to align along the direction perpendicular to the reagent relative velocity vector k, but this kind of product alignment is found to be rather insensitive to j. Furthermore, the distribution of P($\phi_r$) indicates that the rotational angular momentum vector of the OH product is preferentially oriented along the positive direction of y-axis, and such product orientation becomes stronger with increasing j.

• ETRI Journal
• /
• 제35권3호
• /
• pp.397-405
• /
• 2013

In this paper, two sets of spectrally efficient ultra-wideband (UWB) pulses using zinc and frequency-domain Walsh basis functions are proposed. These signals comply with the Federal Communications Commission (FCC) regulations for UWB indoor communications within the stipulated bandwidth of 3.1 GHz to 10.6 GHz. They also demonstrate high energy spectral efficiency by conforming more closely to the FCC mask than other UWB signals described in the literature. The performance of these pulses under various modulation techniques is discussed in this paper, and the proposed pulses are compared with Gaussian monocycles in terms of spectral efficiency, autocorrelation, crosscorrelation, and bit error rate performance.

• Journal of Semiconductor Engineering
• /
• 제2권1호
• /
• pp.125-129
• /
• 2021

As the interest of deep learning, techniques to control the color of images in image processing field are evolving together. However, there is no clear standard for color, and it is not easy to find a way to represent only the color itself like the color-palette. In this paper, we propose a novel color palette extraction system by chroma fine-tuning with reinforcement learning. It helps to recognize the color combination to represent an input image. First, we use RGBY images to create feature maps by transferring the backbone network with well-trained model-weight which is verified at super resolution convolutional neural networks. Second, feature maps are trained to 3 fully connected layers for the color-palette generation with a generative adversarial network (GAN). Third, we use the reinforcement learning method which only changes chroma information of the GAN-output by slightly moving each Y component of YCbCr color gamut of pixel values up and down. The proposed method outperforms existing color palette extraction methods as given the accuracy of 0.9140.

• Bulletin of the Korean Chemical Society
• /
• 제33권2호
• /
• pp.589-596
• /
• 2012

In this paper, the reactive dynamics properties of the reactions Ba + $C_6H_5Br$ and Ba + m-$C_6H_4CH_3Br$ were studied by means of the quasi-classical trajectory method based on the London-Eyring-Polanyi-Sato potential energy surfaces. The vibrational distributions, reaction cross sections, rotational alignments of the products BaBr all were obtained. The peak values of the vibrational distributions are located at $\nu$ = 0 for the reactions Ba + $C_6H_5Br$ and Ba + m-$C_6H_4CH_3Br$ when the collision energies are 1.09 and 1.10 eV, respectively. The reaction cross sections increase with the increasing collision energy, which changes from 0.6 to 1.5 eV. The product rotational alignments deviate from -0.5 and firstly increase and then decrease while the collision energy is increasing, just like that of Heavy+Light-Light system.

• 한방재활의학과학회지
• /
• 제24권1호
• /
• pp.101-109
• /
• 2014

Objectives The relationship between metabolic syndrome causes and bone mineral density (BMD) was explored by taking 60 female chronic low back pain patients with age 61 years old or elder having metabolic syndrome and osteoporosis as study subjects. Methods Fasting blood glucose, serum total-cholesterol, triglyceride and HDL were measured by biochemical tests. Anthropometric elements and blood pressure were measured. Results Average BMD and T-score of part number 1 to 3 of lumbar vertebra were estimated by Quantitative Computed Tomography (QCT). In order to find the relationship between clinical factors and osteoporosis, correlation analysis was done on T-score. Age (r=0.679, p<0.01) had significant negative correlation and weight (r=0.342, p<0.01) and height (r=0.475, p<0.01) had significant positive correlation. Blood glucose, blood pressure, total cholesterol, triglyceride, HDL and body mass index did not have significant correlation. BMD had negative correlation with age (r=0.317, p<0.05). Regression analysis was done by taking T-score as independent variables and taking other factors as dependent variables. It was possible to know that age ($\beta$=-0.471, t=-7.050) with p<0.001, height ($\beta$=0.277, t=4.120) and weight ($\beta$=2.856, t=2.780) with p<0.05 have significant impact on osteoporosis. Conclusions Therefore, it was possible to know that T-score and BMD decrease as one gets older and T-score and BMD increase as one is taller and heavier.

• Bulletin of the Korean Chemical Society
• /
• 제33권9호
• /
• pp.2873-2877
• /
• 2012

Quasi-classical trajectory (QCT) calculations of H+HLi reaction have been carried out on a new potential energy surface of the ground state reported by Prudente et al. [Chem. Phys. Lett. 2009, 474, 18]. The four polarization-dependent differential cross sections have been carried out in the center of mass (CM) frame at various collision energies. The reaction probability for the depletion channel has been studied over a wide collision energy range. It has been found that the collision energy decreases remarkably reaction probability, which shows the expected behavior of the title reaction belonging to an exothermic barrierless reaction. The results are in good agreement with previous RMP results. The P(${\theta}_r$), P(${\phi}_r$) and P(${\theta}_r,\;{\phi}_r$) distributions, the k-k'-j' correlation and the angular distribution of product rotational vectors are presented in the form of polar plots. The average rotational alignment factor <$P_2(j{\prime}{\cdot}k)$> as a function of collision energy is also calculated. The results indicate that the collision energy has a great influence on the polarization of the product rotational angular momentum vector j'.

• 동의생리병리학회지
• /
• 제27권1호
• /
• pp.118-123
• /
• 2013

This study was performed from April, 2007 to August, 2012 with female patients who were being treated for and suffering from chronic lumbar pain for periods of 6 months and over. The 53 female patients were diagnosed with osteoporosis by having a T-Score of <-2.5 in a bone mineral density(BMD), as well as showing signs of metabolic syndrome. This was deduced by taking measurements of blood pressure, carrying out blood-chemical examinations and physical measurements such as weight, height, waist measurement and body mass index(BMI). After 5 minutes rest, the patient's blood pressure, height and weight were measured. BMI was calculated using the equation BMI = weight (Kg)/height ($m^2$). The patients had their blood taken in a fasted state(more than 12hours), the fasting blood sugar, total cholesterol, triglyceride, HDL-cholesterol were measured. The average BMD and T-score were calculated by measuring BMD(mg/cc) of L1-L3 using QCT. In a correlation analysis of the physical examinations, clinical character of metabolic syndrome and T-score, the result showed that age and T-score had a negative correlation(r=-0.699, p<0.01) as did triglyceride and T-score (r=-0.047, p<0.01), where as weight(r=0.239, p<0.05) and height(r-=0.329, p<0.01) and T-score had a positive correlation. There was no significant correlation with total cholesterol, HDL cholesterol, blood sugar, blood pressure and T-score. This study showed that there are significant correlations with age, weight, height and T-score. But there are no significant correlations with total cholesterol, HDL cholesterol, blood sugar, blood pressure and T-score and that these did not influence bone density. Further research with more subjects is required to determine whether there is a correlation of clinical character of metabolic syndrome and T-score.