• Proceedings of the Korean Society of Broadcast Engineers Conference
• /
• 2015.07a
• /
• pp.78-80
• /
• 2015

광적응(Luminance Adaptation; LA) 효과는 영상의 배경 밝기에 따른 왜곡에 대한 시각 인지 민감도가 달라지는 특성을 의미한다. 기존 영상 화질 측정(Image Quality Assessment; IQA) 방법들은 베버의 법칙(Weber' s law) 모델을 이용하여 LA 효과를 IQA 방법에 반영해왔다. 그러나, 이러한 IQA 방법들에 있어서 베버의 법칙 기반 LA 효과 모델은 다음 두 가지 이유로 부정확하게 동작한다: (i) 전통적인 베버의 법칙 모델은 실제 광도(luminance)에 대한 인지 민감도 응답값을 정확히 반영할 수 없다는 것이 밝혀졌다, (ii) 대부분 IQA 방법들은 픽셀 강도 영역에서 계산되지만, 베버의 법칙과 같은 LA 효과 모델들은 광도 영역에서 개발되었다. 따라서 광도와 픽셀 강도간 비선형 관계로 인해 IQA 방법에 반영된 베버의 법칙 기반 LA 효과 모델들은 부정확하게 동작한다. 이 문제를 해결하기 위해, 본 논문에서 처음으로 픽셀 강도 영역에서의 LA 모델을 이론적으로 유도한다. 본 논문에서 제안하는 픽셀 강도 영역에서의 LA 효과 모델은 감마 교정 함수(Gamma correction function)와 광도 영역에서의 LA 효과 모델인 제곱-법칙(power-law) 모델을 기반으로 하는 테일러 급수 확장 근사화를 통해 유도된다. 제안하는 픽셀 강도 영역 LA 효과 모델의 효과를 검증하기 위해, 제안하는 LA 효과 모델을 PSNR 에 도입하여 광범위한 실험을 수행한다. 실험 결과, 제안하는 LA 효과 모델 기반 PSNR 은 PSNR 및 베버의 법칙 기반 PSNR 대비 괄목할 만한 주관적 화질 예측 성능 향상을 보였다.

• Transactions on Electrical and Electronic Materials
• /
• v.18 no.1
• /
• pp.7-12
• /
• 2017

This work takes place in the context of the development of a transport phenomena simulation based on group III nitrides. Gallium and boron nitrides (GaN and BN) are both materials with interesting physical properties; they have a direct band gap and are relatively large compared to other semiconductors. The main objective of this paper is to study the effect of boron content on the electron transport of the ternary compound $B_xGa_{(1-x)}N$ and the effect of the temperature of this alloy at x=50% boron percentage, specifically the piezoelectric, acoustic, and polar optical scatterings as a function of the energy, and the electron energy and drift velocity versus the applied electric field for different boron compositions ($B_xGa_{(1-x)}N$), at various temperatures for $B_{0.5}Ga_{0.5}N$. Monte carlo simulation, was employed and the three valleys of the conduction band (${\Gamma}$, L, X) were considered to be non-parabolic. We focus on the interactions that do not significantly affect the behavior of the electron. Nevertheless, they are introduced to obtain a quantitative description of the electronic dynamics. We find that the form of the velocity-field characteristic changes substantially when the temperature is increased, and a remarkable effect is observed from the boron content in $B_xGa_{(1-x)}N$ alloy and the applied field on the dynamics of holders within the lattice as a result of interaction mechanisms.

• Journal of Korean Neurosurgical Society
• /
• v.63 no.4
• /
• pp.444-454
• /
• 2020

Objective : Glioblastoma multiforme (GBM) is the most aggressive for of brain tumor and treatment often fails due to the invasion of tumor cells into neighboring healthy brain tissues. Activation of the Janus kinase-signal transducer and activator of transcription (JAK/STAT) signaling pathway is essential for normal cellular function including angiogenesis, and has been proposed to have a pivotal role in glioma invasion. This study aimed to determine the dose-dependent effects of ruxolitinib, an inhibitor of JAK, on the interferon (IFN)-I/IFN-α/IFN-β receptor/STAT and IFN-γ/IFN-γ receptor/STAT1 axes of the IFN-receptor-dependent JAK/STAT signaling pathway in glioblastoma invasion and tumorigenesis in U87 glioblastoma tumor spheroids. Methods : We administered three different doses of ruxolitinib (50, 100, and 200 nM) to human U87 glioblastoma spheroids and analyzed the gene expression profiles of IFNs receptors from the JAK/STAT pathway. To evaluate activation of this pathway, we quantified the phosphorylation of JAK and STAT proteins using Western blotting. Results : Quantitative real-time polymerase chain reaction analysis demonstrated that ruxolitinib led to upregulated of the IFN-α and IFN-γ while no change on the hypoxia-inducible factor-1α and vascular endothelial growth factor expression levels. Additionally, we showed that ruxolitinib inhibited phosphorylation of JAK/STAT proteins. The inhibition of IFNs dependent JAK/STAT signaling by ruxolitinib leads to decreases of the U87 cells invasiveness and tumorigenesis. We demonstrate that ruxolitinib may inhibit glioma invasion and tumorigenesis through inhibition of the IFN-induced JAK/STAT signaling pathway. Conclusion : Collectively, our results revealed that ruxolitinib may have therapeutic potential in glioblastomas, possibly by JAK/STAT signaling triggered by IFN-α and IFN-γ.

• Journal of the Korean Chemical Society
• /
• v.8 no.1
• /
• pp.9-14
• /
• 1964

The viscosities of strong electrolytic solutions, such as KCl, KI and NaI have been measured over a fairy wide range of concentration variation (from 0.00002 to 3.7M). It was hoped that a study of the data in the light of modern theories on solution might reveal new relation between viscosity and surface tension of electrolytic solution. To secure more accurate measurements of viscosity and surface tension of the solutions, Ostwald viscometer was made with pyrex glass and modified the timing system for the transit of the meniscus with a new electronics system and with a pulse counter. As the experimental data obtained were in good agreement with the Jone's values, Jones-Dole equations for the electrolytic solutions were deduced, ${\eta}KCl\;=\;1\;+\;0.0052{\sqrt{c}}\;-\;0.01612c\;+\;0.00808c^2\;at\;30^{\circ}C$ ${\eta}KI\;=\;1\;+\;0.0220{\sqrt{c}}\;-\;0.01290c\;+\;0.02988c^2\;at\;25^{\circ}C$${\eta}Na\; =\;1\;+\;0.0240{\sqrt{c}}\;-\;0.0640c\;+\;0.03268c^2\;at\;25^{\circ}C$Gruneisen effect appeared in the dilute solution, whereas anti-Gruneisen effect was found for the extremely dilute solution. No satisfactory interpretation for the variation of the viscosity with concentration can be found at the present.

• Animal cells and systems
• /
• v.16 no.2
• /
• pp.87-94
• /
• 2012

Nur77 is a member of the nuclear receptor 4A (NR4A) subgroup, which has been implicated in energy metabolism. Although Nur77 is found in adipose tissue, where TR4 plays a key role in lipid homeostasis, the role of Nur77 in adipogenesis is still controversial. Although the Nur77 responsive element (AAAGGTCA) is partially overlapped with TR4-binding sites (AGGTCA $n$ AGGTCA: $n$=0-6), the regulatory role of Nur77 in TR4 function associated with adipocyte biology remains unclear. Here, we found that Nur77 inhibits adipogenesis and TR4 transcriptional activity. Treatment with a Nur77 agonist, 1,1-bis(3'-indolyl)-1-($p$-anisyl)-methane, during 3T3-L1 adipocyte differentiation reduced adipogenesis. In reporter gene analysis, Nur77 specifically suppressed TR4 transcription activity but had little effect on $PPAR{\gamma}$ transcription activity. Consistently, Nur77 also suppressed TR4-induced promoter activity of the TR4 target gene PEPCK, which is known to be important for glyceroneogenesis in adipose tissue. Furthermore, Nur77 suppressed TR4 binding to TR4 response elements without direct interaction with TR4, suggesting that Nur77 may inhibit TR4 transcription activity via binding competition for TR4-binding sites. Furthermore, DIM-C-$pPhOCH_3$ substantially suppressed TR4-induced PEPCK expression in 3T3-L1 adipocytes. Together, our data demonstrate that Nur77 plays an inhibitory role in TR4-induced PEPCK expression in 3T3-L1 adipocytes.

• YAKHAK HOEJI
• /
• v.26 no.4
• /
• pp.215-222
• /
• 1982

Among the environmental pollutants, parathion, chloroform and 2, 6-dichlorophenol may impair human health; they may inhibit or reduce the metabolic function of human body and may furthermore cause diseases directly or indirectly. This study was undertaken to investigate the effects on the immune response by intoxication of parathion, chloroform or 2, 6-dichlorophenol. Parathion(1.3mg/kg, olive oil 10ml), chloroform (100mg/kg, olive oil 10ml) were administered via intraperitoneal injection to rats. And 2, 6-dichlorophenol (13mg/kg, olive oil 10ml) was administered via oral injection. After 3 weeks, the rats were intoxicated with the above chemicals and immunized with sheep RBC. After 4 weeks the immune response of rat spleen cells was measured by the Jerne's technique. The results were obtained as follows. 1. There was no change of leukocyte counts by the intoxication of parathion, chloroform and 2, 6-dichlorophenol. 2. Parathion, chloroform and 2, 6-dichlorophenol reduced hemoglobin contents for most intoxicated and immunized groups. 3. Hematocrits were decreased by the intoxication of parathion, chloroform or 2, 6-dichlorophenol significantly. 4. It was determined that total protein, A/G (albumin/globulin), .alpha.-, .betha.-and .gamma.-globulins in rat serum were not changed. 5. Intoxication by parathion, chloroform or 2, 6-dichorophenol reduced the number of hemolytic plaque to the sheep RBC in rat spleen cells. Therefore, the capacity of erythrocyte production and the immune response of rat spleen cells were decreased by the intoxication of parathion, chloroform, or 2, 6-dichlorophenol.

• Journal of radiological science and technology
• /
• v.11 no.2
• /
• pp.65-71
• /
• 1988

Radiation dose outside the radiotherapy treatment field can be significant and therefore is of clinical interest estimating organ dose. We have made measurements of dose at distances up to 70 cm from the central axis of $5{\times}5$, $10{\times}10$, $15{\times}15$, and $25{\times}25$ cm radiation fields of Co-60 ${\gamma}-ray$, at 5 cm depth in water. Contributions to the total secondary radiation dose from water scatter, machine (collimator) scatter and leakage radiation have been seperated. We have found that the component of dose from water scatter can be described by simple exponential function of distance from the central axis of the radiation field for all field sizes. Machine scatter contributes 20 to 60% of the total secondary dose depending on field size and distance from the field. Leakage radiation contributes very little dose, but becomes the dominant componant at distance beyond 40 cm from the central axis. Then, wedges can cause a factor 2 to 3 increase in dose at any point outside the field compared with the dose when no wedge is used. Adding blocks to a treatment field can cause an increase in dose at points outside the field, but the effect is much smaller than the effect of a wedge. From the results of these measurements, doses to selected organs outside the field for specified treatment geometries were estimated, and the potential for reducing these organ doses by additional shielding was assessed.

• Journal of Fashion Business
• /
• v.12 no.3
• /
• pp.87-98
• /
• 2008

The purposes of this study are to measure physiological reactions of human body according to the scalp treatment, a popularized service in beauty care industry and propose efficient ways of scalp treatment. To meet the goals, total 30 applicants without any medical history(5 males and 5 females in 20's, 30's and 40's respectively) were informed on the purpose of experiment hereof and were investigated and received a 30-minute scalp treatment, which combines standardized scalp treatment massage technique proposed by KAT and ITF with another massage technique operated in the beauty salon run by the author of this paper. 5ml of blood samples were taken from each subject before and after the scalp treatment respectively and the blood sample was divided into 3 different tubes for analysis: 1) 2 ml for blood cell analysis, 2) 2ml for enzyme activity measurement, 3) 1ml for hormone level reading. In order to determine effects of scalp treatment on ALP, GOT, GPT, ${\gamma}-GTP$, WBC, RBC, Hb, Hct, Platelet, MCV, MCH and MCHC, all collected data were used for measuring respective levels of these blood substances by means of enzyme reaction measurement, enzyme activity measurement and automated hematology analyzer. Then, all measured data were analyzed through paired t-test using SPSS WIN 11.5. As a result, the scalp treatment is associated with improving hepatic function, facilitating blood circulation and helping blood coagulation and hemostasis in a effective way. Therefore, it would be necessary to conduct further studies on this subject related to anemia in the future.

• Advances in Energy Research
• /
• v.8 no.2
• /
• pp.95-110
• /
• 2022

Wind energy can be utilized for the generation of electricity, due to significant wind potential at different parts of the world, some countries have already been generating of electricity through wind. Pakistan is still well behind and has not yet made any appreciable effort for the same. The objective of this work was to add some new strategies to calculate Weibull parameters and assess wind energy potential. A new approach calculates Weibull parameters; we also developed an alternate formula to calculate shape parameters instead of the gamma function. We obtained k (shape parameter) and c (scale parameter) for two-parameter Weibull distribution using five statistical methods for five different cities in Pakistan. Maximum likelihood method, Modified Maximum likelihood Method, Method of Moment, Energy Pattern Method, Empirical Method, and have been to calculate and differentiate the values of (shape parameter) k and (scale parameter) c. The performance of these five methods is estimated using the Goodness-of-Fit Test, including root mean square error, mean absolute bias error, mean absolute percentage error, and chi-square error. The daily 10-minute average values of wind speed data (obtained from energydata.info) of different cities of Pakistan for the year 2016 are used to estimate the Weibull parameters. The study finds that Hyderabad city has the largest wind potential than Karachi, Quetta, Lahore, and Peshawar. Hyderabad and Karachi are two possible sites where wind turbines can produce reasonable electricity.

• Journal of Ginseng Research
• /
• v.27 no.4
• /
• pp.165-170
• /
• 2003

The clinical efficacies of Korean Red Ginseng for improving sexual function has been reported only by self-reporting questionnaires.AVS-Penogram is a method evaluating natural penile blood flow changes by Gamma-camera after intravenous injection of Techmetium 99$\^$m/-RBC and also stimulating by erotic video tape. To more objectively evaluate the efficacies of Korean Red Ginseng for erectile function, we applied AVS-Penogram as a objective diagnostic tool. AVS-Penogram studies were done in 28 patients with erectile dysfunction after administration of Red Ginseng(19) or placebo(9) group. The pattern of AVS-Penogram before medication were normal type in 4, impossible in 2, unstable in 20, delayed in 1, and mixed in 1. The unstable type were the most prevalent observed in 71.4% of all patients. The patterns of AVS-penogram were 2.2. 13.1 in Red Ginseng group, while in placebo group normal 2, unstable 7. After 4 weeks in Red Ginseng group, there were 3 cases of improved penogram findings, while only 1 in placebo group. There were no statistical significancies in the type of penogram changes on both group. But the maximum radioactivity were improved in 11 patients(57.9%) in Red Ginseng group, while 2(22.2%) in placebo group. There were statistical significancies in comparing the maximal radioactivity of penogram on both group. These AVS-Penogram findings shows, encouraging results of by increased penile blood flow Korean Red Ginseng our medication. Further study is more needed to reconfirm these results by more concentrated active formulations of sapanonin St other active ginsenosides. These promising results will lead to develop a new remedy for erectile dysfunction by Korean Red Ginseng