• Journal of Broadcast Engineering
• /
• v.14 no.1
• /
• pp.59-69
• /
• 2009

A bi-directional symmetric prediction technique has been developed to improve coding efficiency of B-slice and to reduce the computational complexity required to estimate two motion vectors. On the contrary to the conventional bi-directional mode which encodes both forward and backward motion vectors, it only encodes a single forward motion vector, and the missing backward motion vector is derived in a symmetric way from the forward motion vector using temporal distance between forward/backward reference frames to and from the current B picture. Since the backward motion vector is derived from the forward motion vector, it can halve the computational complexity for motion estimation, and also reduces motion vector data to encode. This technique always derives the backward motion vector from the forward motion vector, however, there are cases when the forward motion vector is better to be derived from the backward motion vector especially in scene changes. In this paper, we generalize the idea of the symmetric coding with forward motion vector coding, and propose a new symmetric coding with backward motion vector coding and adaptive selection between the conventional symmetric mode and the proposed symmetric mode based on rate-distortion optimization.

• Journal of Periodontal and Implant Science
• /
• v.31 no.1
• /
• pp.21-41
• /
• 2001

The goal of Periodontal treatment is predictable periodontal regeneration. But until now, many products including GTR materials and growth factors are beyond of complete regeneration. BMP can induce ectopic bone formation when implanted into sites such as rat muscle and can greatly enhance healing of bony defects when applied exogenously. BMP can promote periodontal regeneration by their ability to stimulate new bone and new cementum formation. But little is known about optimal conditions required for the application. Root conditioning is used for bioacive root change so altered root surface provides a substrate that promotes chemotaxis, migration and attachment of peridontal cells encouraging connective attachment to the denuded root surface. The aim of this study is to investigate whether the acid conditioning change effect of rhBMP-2 on human periodontal ligament cell and osteoblast cell line. 288 periodontally involved root dentin slices are divided into 6 groups, each 48, 1)control, 2)treated with BMP, 3)treated with citric acid 4)treated with citric acid+BMP 5)treated with tetracycline 6)treated with TC+BMP. Each group was devided half, so 12 root dentin slices were seeded with periodontal ligament cells and 12 were seeded with osteoblasts. At day 2 and 7, cell number, protein assay, ALP activitiy was measured. To investigate morphology of cultured cells, SEM was employed. Statistical analysis was performed with SPSS 8.0 either t-test or ANOVA test. The results are ; Protein assay and cell number was slightly decreased in CA+BMP group compared to Ca group but it was not statistically significant and ALP activity was much more increased in CA+BMP group compared to CA group so there was no statistically significance between BMP and CA+BMP group and statistically significant compared to control group. Cell number and protein assay was slightly increased in TC group and ALP activity was much less the BMP group and CA group. Cell number and protein and ALP activity was not much increased in TC+BMP group. TC group and TC+BMP group showed cell morphology change in SEM. This results suggested that application of root surface with citric acid before BMP treatment might give better result in periodontal regeneration.

• The Journal of Dong Guk Oriental Medicine
• /
• v.1
• /
• pp.55-80
• /
• 1992

In order to examine that the effect of Sam Hwa San, circulating the vital energy of Sam Cho and controlling body fluid metabolism, gives any influence on renal function, changes in the urine flow, eletrolytes excretion, plasma aldosterone concentration and renin activity were observed after intravenous infusion of the Sam Hwa San extract in rabbit. Also in vitro effect of the herb extract on oxygen consumption in renal cortical slices and ATPase activity in kidney microsomes was measured. The following results were obtained : 1. The urine flow was markedly increased at 10 min after intravenous infusion of the Sam Hwa San extract($0.134{\pm}0.015$ vs. $0.433{\pm}0.046ml/min.kg$), but return ed to normal value after 40 min of infusion. 2. The glomerular filtration rate was significantly increased at 10 min after in travenous infusion of the Sam Hwa San extract, and the renal plasma flow at 10 and 20 min after infusion of the Sam Hwa San extract, following return to normal value. 3. $Na^+$ excretion was significantly increased during 10-40 min after intravenous infusion of the Sam Hwa San extract, although showed the maximal rate at 10-20 min. The fractional $Na^+$ excretion was also increased during 10-40 min. $K^+$ excretion was rapidly increased at 10 min after the intravenous Infusion of the Sam Hwa San extract and then gradually decreased to normal level at 40 min. The fractional $K^+$ excretion was significantly increased during 10-40 min after the intravenous infusion of the Sam Hwa San extract. 4. The plasma aldosterone concentration and renin activity were not altered by the infusion of the Sam Hwa San extract. 5. The ouabain-sensitive oxygen consumption of renal cortical slices was significantly reduced by the Sam Hwa San extract(0.5 and 1.0 vol.%). 6. The Na-K-ATPase activity of renal microsomes was strongly inhibited by the Sam Hwa San extract(0.5 and 1.0 vol.%). These results suggest that the Sam Hwa San causes a strong diuretic effect which results from reduction of Na reabsorption in renal tubule by a direct inhibition of Na-pump and, in part, from all increase in renal blood flow. In clinic, it is considered to obtain the therapeutic effect in body fluid metabolism disharmony to cause the circular disorder of vital energy.

• Journal of Korean Academy of Nursing
• /
• v.13 no.2
• /
• pp.87-104
• /
• 1983

It has been well documented that animals exposed to cold show increased activity of thyroid gland. The calorigenic action of thyroid hormone has been demonstrated by a variety of in vivo and in vitro studies. According to Edelman et al., the thyroid thermogenesis is due to activation of energy consuming processes, especially the active sodium transport by the hormone in target tissues. If so, the increase in thyroid activity during cold exposure should induce increased capacity of sodium transport in target tissue and the change in tissue metabolism should be precisely correlated with the change in Na+_K+_ATPase activity of the tissue. This possibility was tested in the present study: in one series, changes in oxygen consumption and Na+_K+_-ATPase activity of liver preparations were measured in rats as a function of thyroid status, in order to establish the effect of thyroid hormone on the tissue respiration and enzyme system in another series, the effect of cold stimulus on the serum thyroid hormone level, hepatic tissue oxygen consumption and Na+_K+_ATPase activity in rats. The results obtained are as follows: 1. The Na+_dependent oxygen consumption of liver slices, the oxygen consumption of liver mitochondria and the Na+_K+_ATPase activity of liver preparations were significantly inhibited in hypothyroidism and activated in hyperthyroidism. Kinetic analysis indicated that the Vmax. of Na+_K+_ATPase was decreased in hypothyroidism and increased in hyperth)'roidism. 2. In cold exposed rats, the serum triiodothyronine (T₃) level increased rapidly during the initial one day of cold exposure, then declined slowly to the control level after two weeks. The serum thyroxine (T₄) level decreased gradually throughout the cold exposure. Accordingly the T₃/T₄ratio increased. The mitochondrial oxygen consumption and the Na+_dependent oxygen consumption of liver slices increased during the first two days and then remained unchanged thereafter The activity of the Na+_K+_ATPase in liver preparations increased during cold exposure with a time course similar to that of oxygen consumption. Kinetic analysis indicated that the Vmax. of Na+_K+_ATPase increased. 3. Once the animal was adapted to cold, induction of hypothyroidism did not significantly alter the hepatic oxygen consumption and Na+_K+_ATPase activity. These results indicate that: 1) thyroid hormone increases capacities of mitochondrial respiration and active sodium transport in target tissues such as liver; 2) the increased T₃level during the initial period of cold exposure facilitates biosynthesis of Na+_K+_ATPase and mitochondrial enzymes for oxidative phosphorylation, leading to enhanced production and utilization of ATP, hence heat production.

• Progress in Medical Physics
• /
• v.9 no.4
• /
• pp.201-206
• /
• 1998

IMRT optimization method on multiple slice has been developed by using gradient based algorithm. On about 10-30 CT slices including treatment region of a patient, dose optimization has been performed slice by slice to meet the condition that each organ should be exposed below maximum tolerable doses and that the tumor dose within the range of 100$\pm$5 %. Field size was limited to 8$\times$8 cm$^2$ and in this condition, beam divergence was not taken into account to calculate dose distribution. Total dose distribution was calculated by superposing each beamlet whose dose distribution had been precalculated. In order to investigate beam number dependency, dose optimization was performed for one, three, five, seven, and nine coplanar beams and then each optimization index was evaluated. It is found that optimization time was proportional to number of slices to be optimized, and the most efficient plan was obtained from the case of three-to-seven incident beams with respect to calculation time and optimization index. In conclusion, dose optimization of multiple slice was able to be obtained by repeating dose optimization of single slice under condition that the beam size is not too large to ignore beam divergence. And it turns out that result of dose optimization was so sensitive to the position of isocenter that some method to optimize isocenter position is needed to improve it.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.45 no.8
• /
• pp.1192-1201
• /
• 2016

This study was conducted to investigate sensory characteristics and consumer acceptance of sliced raw fish. The two most popular varieties in Korea, flounder and rockfish, were used. Samples of each variety were prepared as follows to create consistent perceptible sensory differences: 'fresh' (consumed within 2 h after sacrifice), 'aged' (stored at $1^{\circ}C$ for 24 h), 'frozen' (frozen at $-16^{\circ}C$ for 23 h then thawed at $23.5^{\circ}C$for 1 h), and 'immersed' (immersed in sterilized water at $1^{\circ}C$ for 24 h). Sensory profiles of samples were determined through quantitative descriptive analysis using 10 trained panelists. Consumer acceptance test was conducted using 47 consumers. Analyses of variance were conducted to test significance of differences in sensory profiles and hedonic ratings among samples. Consumers were clustered according to their overall liking scores, and their preference patterns were cross-checked with sensory profiles. For both fish varieties, 'fresh' was characterized by stronger hardness, cohesiveness, springiness, cartilage-like texture (applied to only rockfish), and fishy flavor, whereas 'frozen' and 'immersed' were distinguished from other samples for their stronger wetness, juiciness, and fresh fish flavor than those of other samples. 'Aged' was significantly less hard, cohesive, and springy than 'fresh' as well as less juicy and wet than 'frozen' and 'immersed'. Consumers significantly preferred 'fresh' flounder and rockfish to others for their strong cohesiveness and springiness, indicating textural attributes were main factors affecting consumer preferences. However, for both flounder and rockfish, 40~50% of respondents preferred 'frozen' and 'immersed' to 'fresh' for their tenderness and fresh fish flavor. For this group of consumers, flavor liking had a greater effect on overall preference than texture preference. The result suggests that cohesive and springy textures and fresh fish flavor are major drivers of preferences for raw fish slices, but their relative importance and optimal levels varied across individual consumers.

• Journal of Broadcast Engineering
• /
• v.17 no.4
• /
• pp.625-633
• /
• 2012

Extended Depth of Focus (EDF) algorithms for extracting three-dimensional (3D) information from a set of optical image slices are studied by many researches recently. Due to the limited depth of focus of the microscope, only a small portion of the image slices are in focus. Most of the EDF algorithms try to find the in-focus area to generate a single focused image and a 3D depth image. Inherent to most image processing algorithms, the EDF algorithms need parameters to be properly initialized to perform successfully. In this paper, we select three popular transform-based EDF algorithms which are each based on pyramid, wavelet transform, and complex wavelet transform, and study the performance of the algorithms according to the initialization of its parameters. The parameters we considered consist of the number of levels used in the transform, the selection of the lowest level image, the window size used in high frequency filter, the noise reduction method, etc. Through extended simulation, we find a good relationship between the initialization of the parameters and the properties of both the texture and 3D ground truth images. Typically, we find that a proper initialization of the parameters improve the algorithm performance 3dB ~ 19dB over a default initialization in recovering the 3D information.

• Journal of the Institute of Convergence Signal Processing
• /
• v.12 no.4
• /
• pp.267-273
• /
• 2011

In this paper, we proposed the method to detect brain tumor region in MR images. Our method is composed of 3 parts, detection of tumor slice, detection of tumor region and tumor boundary detection. In the tumor slice detection step, a slice which contains tumor regions is distinguished using symmetric analysis in 3D brain volume. The tumor region detection step is the process to segment the tumor region in the slice distinguished as a tumor slice. And tumor region is finally detected, using spatial feature and symmetric analysis based on the cluster information. The process for detecting tumor slice and tumor region have advantages which are robust for noise and requires less computational time, using the knowledge of the brain tumor and cluster-based on symmetric analysis. And we use the level set method with fast marching algorithm to detect the tumor boundary. It is performed to find the tumor boundary for all other slices using the initial seeds derived from the previous or later slice until the tumor region is vanished. It requires less computational time because every procedure is not performed for all slices.

• The Korean Journal of Nuclear Medicine
• /
• v.28 no.2
• /
• pp.172-176
• /
• 1994

As the Tc-99m-MIBI myocardial SPECT demonstrated wide application in the diagnosis of myocardial function, the quantitative and severity-dependent information is currently re quired. In this study, we proposed a computerized method for scoring the fixed defects in terms of extent-weighted severity and for identifying the reversibility in ischemic regions. At the first stage of this method, the transverse slices were reconstructed with 0.4 Nyquist freq. and order 5 Butterworth filter. From the oblique/sagittal slices, maximal count per pixel circumferential profiles were extracted for each sector, and then stress/redist. polar maps were normalized and plotted. For reversibility, the stress polar map was subtracted from the de-layed image and positive-valued pixels were categorized into three grades. The extent-weight-ed severity scores were calculated using the assigned grades and their number of pixels. This procedure was done automatically and the reversibility and severity scores were produced for each of the coronary territories (LAD, RCA, LCX) or any combination of these. Clinical ap-plication has shown that the changes In reversibility scores after PTCA were correlated linearly with the pre PTCA scores(r>0.8) in postinfarct cases as well as in angina, and severity scores of persistent defects in stress/rest SPECT study matched to the regional ejection fraction and visual analysis of regional wall motion of gated blood pool scan(r>0.6). We conclude that the computerized severity scoring method for the analysis of myocardial SPECT could be useful in the assessment of the myocardial ischemia and fixed defect.

• Korean Journal of Food Science and Technology
• /
• v.20 no.3
• /
• pp.380-384
• /
• 1988

The coefficients of the hot-air and freeze dried garlic isotherms and the critical water activities of these were estimated to be 0.85-0.94 by the linear regression and 0.58-0.60 by the sensory evaluation and ${\Delta}E$ value. Water adsorption rate(K) of hot-air dried garlic packaged with $48{\mu}m$ low density polyethylene(LDPE) decreased from $0.12g\;H_2O/100g/day\;to\;0.093g\;H_2O$/100g/day with decreasing the package dimension from $0.051m^2\;to\;0.029m^2\;at\;40^{\circ}C$ and 75% RH, and that of freeze dried one decreased from $0.17g\;H_2O/100g/day\;to\;0.12g\;H_2O$/100g/day as the filling weight increased from 50g to 10g in the package of $0.051m^2$. Shelf-life of hot-air dried garlic packaged with $80{\mu}m$ LDPE were 99days at $40^{\circ}C,\;283day\;at\;30^{\circ}C\;and\;455\;days\;at\;15^{\circ}C$ in the 75% RH. The differences of water contents between predicted data with water vapor permeability of the conventional method and experimental data were 0-1.5% in the water content range of around 13-18%, but about 2 in the water content range of around 8-11%.