• Journal of Broadcast Engineering
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• v.2 no.1
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• pp.16-23
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• 1997

Among the main technologies to implement 3D TV succeeding HDTV, multi-viewpoint image display technique is rising as an important issue, which can display the viewpoint-dependent images corresponding to viewer's position. This paper presents a novel method that solves too much computational overload that is main drawback of previous methods. Using down sampling technique, multiresolution EPIs are made from multi-viewpoint image set and trace lines are detected in the lowest resolution EPI. The parameters of detected trace lines are transferred to higher resolution EPIs and revised by utilizing the information of the previous resolution EPI. This procedure is iterated until orignal resolution EPI. Using the proposed method, we have achieved the reduction of computational time and the robustness to noise in comparison to previous method.

• Korean Journal of Optics and Photonics
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• v.22 no.3
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• pp.141-150
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• 2011

Although significant amount of research has been done to develop LED lamp packages for improved performance, no standard theories or guidelines have been established yet for designing LED lamp packages. In this paper, the photon extraction efficiency depending on both the InGaN/Sapphire LED chip structure and its attachment schemes for chip mounting has been analyzed by using the Monte Carlo photon simulation method. Based on the results of the analysis, we have derived guidelines for LED lamp package design, which can be utilized in industries or research institutes for designing new LED lamp packages optimized for particular applications.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.8
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• pp.3651-3657
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• 2014

Hepatocellular carcinoma (HCC) has a relatively higher incidence in many countries of Asia. Globally, HCC has a high fatality rate and short survival. Epirubicin, a doxorubicin analogue, may be administered alone or in combination with other agents to treat primary liver cancer and metastatic diseases. However, the toxic effects of epirubicin to normal tissues and cells have been one of the major obstacles to successful cancer chemotherapy. Here, we investigated the effects of epirubicin in combination with kappa-selenocarrageenan on mice with H22 implanted tumors and HepG-2 cell proliferation, immune organ index, morphology, cell cycle and related protein expressions in vivo and in vitro with sequential drug exposure. The inhibitory rate of tumor growth in vivo was calculated. Drug sensitivity was measured by MTT assay, and the King's principle was used to evaluate the interaction of drug combination. Morphological changes were observed by fluorescent microscopy. Cell cycle changes were analyzed by flow cytometry. Expression of cyclin A, Cdc25A and Cdk2 were detected by Western blotting. In vivo results demonstrated that the inhibitory rate of EPI combined with KSC was higher than that of KSC or EPI alone, and the Q value indicated an additive effect. In addition, KSC could significantly raise the thymus and spleen indices of mice with H22 implanted tumors. In the drug sensitivity assay in vitro, exposure to KSC and EPI simultaneously was more effective than exposure sequentially in HepG-2 cells, while exposure to KSC prior to EPI was more effective than exposure to EPI prior to KSC. Q values showed an additive effect in the simultaneous group and antagonistic effects in the sequential groups. Morphological analysis showed similar results to the drug sensitivity assay. Cell cycle analysis revealed that exposure to KSC or EPI alone arrested the cells in S phase in HepG-2 cells, exposure to KSC and EPI simultaneously caused accumulation in the S phase, an effect caused by either KSC or EPI. Expression of cyclin A, Cdc25A and Cdk2 protein was down-regulated following exposure to KSC and EPI alone or in combination, exposure to KSC and EPI simultaneously resulting in the lowest values. Taken together, our findings suggest that KSC in combination with EPI might have potential as a new therapeutic regimen against HCC.

• Korean Journal of Optics and Photonics
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• v.16 no.3
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• pp.275-286
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• 2005

The performance of the InGaN LED's in terms of the photon extraction efficiency has been analyzed by the Monte Carlo photon simulation method. Simulation results show that the sidewall slanting scheme, which works well for the AlInGaP or InGaN/SiC LED, plays a very minimal role in InGaN/sapphire LED's. In contrast to InGaN/SiC LED's, the lower refractive index sapphire substrate restricts the generated photons to enter the substrate, minimizing the chances for the photons to be deflected by the slanted sidewalls of the epitaxial semiconductor layers that are usually very thin. The limited photon transmission to the sapphire substrate also degrades the. photon extraction efficiency especially in the epitaxial-side down mount. One approach to exploit the photon extraction potential of the epitaxial-side down mount may be to texture the substrate-epitaxy interface. In this case, randomized photon deflection off the textured interface directly increases the number of the photons entering the sapphire substrate, from which they easily couple out of the chip and thereby improving the photon extraction efficiency drastically.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.12
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• pp.11-20
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• 2011

PSALI is referred to the supplementary lighting for the interior lighting under the daily lighting situation, and pursuant to the pertinent regulations in energy savings design standard and others in recent architecture works, the importance thereof has been increasing gradually coupled with the energy performance index (EPI), energy savings plan and the like as well as expansion of submittal and implementation policies. However, this type of PSALI studies indeed have a number of limitations since it has surrounding environmental conditions in direction, season, region, climate, time, opening rate, window area ratio, actual index, reflection rate of finishing materials and others in the architecture work as well as frequent changes in interior lighting environment for variables in daily light volume flowing into the interior, and others. Therefore, this study has analyzed existing advance research cases to produce the actual-sized model and scaled-down model, and installed the artificial lighting of LED light source possible to reproduce with same capability on both models. As a result of comparison and analysis of the artificial lighting with the key light, it has certain level of error rate from the scaled down lighting device in certain rate and actual model butit was noticeably significant within specific scope.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2000.05a
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• pp.470-473
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• 2000

The metal-oxide-semiconductor field-effect transistor(MOSFET) has undergone many changes in the last decade in response to the constant demand for increased speed, decreased power, and increased patting density. The devices are scaled down day by day. Therefore, This paper investigates how MOSFET structures influence on transport properties in according to change of channel length and bias and, observes impact ionization between the drain and the gate. This paper proposes three models, i.e., conventional MOSFET, LDD MOSFET and EPI MOSFET. The gate lengths are 0.3$\mu\textrm{m}$ 0.15$\mu\textrm{m}$, 0.075$\mu\textrm{m}$ and scaling factor is λ = 2. We have presented MOSFET's characteristics such as I-V characteristic, impart ionization, electric field, using the TCAD. We have analyzed the adaptive channel and doping influences

• Journal of Integrative Natural Science
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• v.16 no.2
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• pp.61-67
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• 2023

Human body ages differently due to environmental, genetic and pathological factors. DNA methylation patterns also differs depending on various factors such as aging and several other diseases. The aging clock model, which uses these differences to predict age, analyzes DNA methylation patterns, recognizes age-specific patterns, predicts age, and grasps the speed and degree of aging. Aging occurs in everyone and causes various problems such as deterioration of physical ability and complications. Alzheimer's disease is a disease associated with aging and the most common brain degenerative disease. This disease causes various cognitive functions disabilities such as dementia and impaired judgment to motor functions, making daily life impossible. It has been reported that the incidence and progression of this disease increase with aging, and that increased phosphorylation of Aβ and tau proteins, which are overexpressed in this disease and accelerates epigenetic aging. It has also been reported that DNA methylation is significantly increased in the hippocampus and entorhinal cortex of Alzheimer's disease patients. Therefore, we calculated the biological age using the Epi clock, a pan-tissue aging clock model, and confirmed that the epigenetic age of patients suffering from Alzheimer's disease is lower than their actual age. Also, it was confirmed to slow down aging.

• Journal of Veterinary Clinics
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• v.18 no.1
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• pp.7-13
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• 2001

Depending on the degree of exocrine pancreatic insufficiency, there are inconsistent values in the serum trypsin-like immunoreactivity (TLI), hematology, and serology. To determine the correlation between those values and complete pancreatic insufficiency, 10 pancreatectomized dogs as the treated group and 10 sham operation dogs as control group were used. The entire treated group showed significant decrease in serum TLI level from 2.63$\pm$0.20 ng/ml (day 0) to 1.81$\pm$0.43 ng/ml at day 1 after the pancreatectomy (p<0.05) and the decline maintained till the end of the experiment. Blood glucose level gradually increased, but albumin level showed significant decrease (p<0.05) at day 1 and maintained the decline. Three clinical signs were observed such as depression, vomiting, and diarrhea. The entire treated group showed diarrhea throughout the experiment, but depression and vomiting were gradually diminished. The activity of serum alkaline phosphatase in the treated group increased till day 2 then decreased, on the other hand, control group showed continuous increase till day 4, and then decreased. Only experimental group showed the increased alanine aminotransferase activity at day 1. Serum lipase activity in the treated group jumped up at day 1 and then dropped down, which was even lower than the control. Regarding serum amlyase activity gradually decreased. According to these results, the assay of trypsin-like immunoreactivity showed the consistent result, so it suggests that TLI is an useful tool to determine the pancreatic exocrine function and possible diagnosis of exocrine pancreatic insufficiency compared to the simple assay of plasma amylase and lipase.

• Proceedings of the Materials Research Society of Korea Conference
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• 2003.11a
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• pp.20-20
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• 2003

We developed 30 ㎽-AlInGaN based violet laser diodes. The fabrication procedures of the laser diodes are described as follows. Firstly, GaN layers having very low defect density were grown on sapphire substrates by lateral epitaxial overgrowth method. The typical dislocation density was about 1-3$\times$10$^{6}$ /$\textrm{cm}^2$ at the wing region. Secondly, AlInGaN laser structures were grown on LEO-GaN/sapphire substrates by MOCVD. UV activation method, instead of conventional annealing, was conducted to achieve good p-type conduction. Thirdly, ridge stripe laser structures were fabricated. The cavity mirrors were formed by cleaving method. Three pairs of SiO$_2$ and TiO$_2$ layers were deposited on the rear facet for mirror coating. Lastly, laser diode chips were mounted on AlN submount wafers by epi-down bonding method. The lifetime of the laser diodes was over 10,000 hrs at room temperature under automatic power controlled condition. We expect the performance of the LDs to be improved by the optimization of the growth and fabrication process. The detailed characteristics and important issues of the laser diodes will be discussed at the conference.