• Title/Summary/Keyword: AR(1)

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Investigation of NH4OH on Zircaloy-4 Surfaces Using Electron Emission Spectroscopy

  • Jung, Hye-Yoon;Kang, Yong-Cheol
    • Bulletin of the Korean Chemical Society
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    • v.28 no.10
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    • pp.1751-1755
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    • 2007
  • The interaction of ammonium hydroxide (NH4OH) with zircaloy-4 (Zry-4) was investigated using X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) methods. In order to study the surface chemistry of NH4OH/Zry-4 system, the binding energies of N1s, O1s and Zr3d electrons were monitored. The N1s peak intensity was remarkably increased by following cycles of Ar+ sputtering of NH4OH dosed Zry-4 surface at room temperature. Because the nitrogen stayed under the subsurface region was diffused out onto the Zry-4 surface after oxygen concentration was decreased. These could be occurred after the surface oxygen was diffused into the bulk or desorbed out from the surface until Ar+ fluence was 6.0 × 1016 Ar+/cm2 then the surface was relatively atomic deficient state. The O1s peak intensity was decreased by stepwise Ar+ sputtering. After many cycles of Ar+ sputtering, the peak intensities of Zr3d peaks did not change much but the shape of the peak clearly did change. This implies that the oxidation state of zirconium was changed during stepwise Ar+ sputtering of NH4OH/Zry-4. The Zr3d peak intensity of zirconium nitride (ZrNx) increased as the intensity of N1s (from zirconium nitride) increased but the Zr3d peak intensity of zirconium oxide (ZrOx) decreased due to the depopulation of the oxygen species on the surface region. We also observed that the peak intensity of Zr4+ was nearly same after Ar+ sputtering processes but the peak intensity of metallic zirconium increased compared to that of before the sputtering process was performed.

Selection of the optimal herbal composition of pomegranate concentrated powder from aqueous extracts of Eucommiae Cortex and Achyranthis Radix to treat osteoarthritis in rats

  • Choi, Beom-Rak;Ku, Sae-Kwang;Kang, Su-Jin;Park, Hye-Rim;Sung, Mi-Sun;Lee, Young-Joon;Park, Ki-Moon
    • The Journal of Korean Medicine
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    • v.38 no.4
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    • pp.11-40
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    • 2017
  • Objectives: We investigated whether a mixture of the main component of pomegranate concentrated powder (PCP) with appropriate proportions of Eucommiae Cortex (EC) and Achyranthis Radix (AR) could act synergistically as an effective treatment for osteoarthritis (OA). Methods: In order to evaluate the effects of PCP, EC, and AR against OA, knee thicknesses, maximum extension angle of each knee, anti - inflammation effects, the transcript levels of chondrogenic genes mRNA expressions in femur and tibia articular cartilage (AC) with synovial membrane (SM) were analyzed. In addition, the histopathology and immunohistochemistry of the femur and tibia AC or SM were performed. Results: The surgically-induced OA signs in rats were significantly inhibited by 28 days of continuous treatment of PCP, EC and AR single formulas, and PCP with EC:AR mixed formulas. Especially, PCP with EC:AR 4:1, 2:1 and 1:1 mixed formula treatment constantly showed significantly more favorable inhibitory activities, as compared with those of single formula of PCP, EC and AR treated rats. Conclusion: PCP and EC:AR 4:1 mixed formula showed similar OA refinement effects through potent anti-inflammatory pathways as compared with those of diclofenac treatment, and showed additional chondrocyte proliferating effects on the both femur and tibia AC.

A literature Review of Single Nucleotide Polymorphisms in Obesity Genes (비만 유전자 단일 염기 다형성 문헌 고찰)

  • Kim, Sung-Soo;Song, Hee-Ok
    • Journal of Korean Medicine for Obesity Research
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    • v.4 no.1
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    • pp.139-160
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    • 2004
  • The obesity is detrimental to the health of people living in affluent societies. Individual differences in energy metabolism are caused primarily by single nucleotide polymorphisms(SNPs), some of which promote the development of obesity-related type 2 diabetes mellitus. Type 2 diabetes mellitus is a common multifactorial genetic syndrome, which is determined by several different genes and environmental factors. In this review, five major conclusions are reached: (1)To be clinically significant, SNPs must be relevant, prevalent, modifiable, and measurable. (2)Differences in SNPs may have been caused by famine, ultraviolet light, alcohol, climate, agricultural revolution. livestock, lactase persistence, and westernized lifestyle. (3)Candidate obesity genes of calorie intake restriction are SIM 1, MC3R, MC4R, AGRP, CART, CCK, CNTFR, DRD2, Ghrelin, 5-HT receptor, NPY, PON and those of energy metabolism are LEP, LEPR, UCP1, UCP2, UCP3, B2AR, B3AR, PGC-1, Androgen receptor and those of fat mobilization are AGT, ACE, ADA, APM1, Apolipoproteins, PPAR, FABP, FOXC2, GCGR, $11-{\beta}HSDI$, LDLR, Hormonal sensitive lipase, Perilipin, $TNF-{\alpha}$, $TNF-{\beta}$ (4)Candidate obesity genes in the eastern are NPY, LEP, LEPR, UCP1, UCP2, UCP3, B2AR, B3AR, ACE, APM1, PPAR, and FABP. (5)Candidate obesity genes in type 2 diabetes mellitus are MC3R, MC4R, B2AR, B3AR, ADA, APM1, PPAR, FABP, FOXC2, PC1, PC2, ABCC8, CAPN10, CYP19, CYP7, ENPP1, GCK, GYS1, IGF, IL-6, Insulin receptor, IRS, and LPL. The discovery of SNPs will lead to a greater understanding of the pathogenesis of obesity and to better diagnostics, treatment, and eventually prevention.

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Fracture Behavior of Oxide Scales and Influence of Oxide Scales on the Strength of Materials (산화피막의 파괴거동 및 산화피막이 소지금속의 기계적 강도에 미치는 영향)

  • ;;Narita Toshio
    • Transactions of Materials Processing
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    • v.13 no.1
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    • pp.72-77
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    • 2004
  • An Fe-25Cr steel was oxidized in Ar atmosphere at 973K with and without applying external stress of 30∼35 MPa. A 0.1$\mu\textrm{m}$ thick $Cr_2O_3$ scales formed during pre-treatment in Ar atmosphere. Initiation of cracking on the oxide scales took place at grain boundaries during the end of second creep stage, in which cracks were found nearly perpendicular to the tensile directions. On the contrary, a scale developed in $N_2$-0.1%$SO_2$ displaced a poor adherence on the metal substrate. In this sample, a fast grown of scales was observed during creep deformation, and the strength of materials was much lower than in Ar. The creep strain rate of $1.5{\times}10^{-7}/s$ and $5.8{\times}10^{-7}/s$ was determined in Ar and in $N_2$-0.1%$SO_2$ under 30MPa, respectively.

$^{40}Ar^{/39}Ar$ Age of the Volcanic Pebbles Within the Silla Conglomerate and the Deposition Timing of the Hayang Group (백악기 신라역암 내 화산암력의 $^{40}Ar^{/39}Ar$ 연대 및 하양층군의 퇴적시기에 대한 고찰)

  • Kim Chan-Soo;Park Kye-Hun;Paik In-Sung
    • The Journal of the Petrological Society of Korea
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    • v.14 no.1
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    • pp.38-44
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    • 2005
  • Hornblende $^{40}Ar/^{39}Ar$ age of $113.4{\pm}2.4(2{\sigma})$ Ma was determined from the volcanic pebble of the Silla Conglomerate which belongs to the Hayang Group of the Cretaceous Gyeongsang Supergroup. This age corresponds to the top of Aptian. Based on the reported age information, onset and duration of deposition of the constituting formations of the Hayang Group are constrained as follows; deposition of the Jindong Formation started from ca. 96~97 Ma and lasted for about 15 Ma. Therefore, Jindong Formation was deposited since Cenomanian to Santonian and it is likely to be extended to the early Campanian. We propose 81~80 Ma, which is in early Campanian, as the boundary between Hayang and Yucheon Groups. We suggest that the Silla Conglomerate was deposited during the early Albian and the Haman Formation was deposited during the rest of the Albian and also during the Cenomanian. The Chilgok Formation seems to be deposited during the late Aptian.

The effect of Astragali Radix and Armeniacae Semen on the apoptosis of immunocytes and nitric oxide production from peritoneal macrophages (황기와 행인(杏仁)이 면역세포(免疫細胞)의 Apoptosis 및 Nitric Oxide에 미치는 효과(效果))

  • Jeong Hyun-Woo;Moon Han-Ju
    • Herbal Formula Science
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    • v.6 no.1
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    • pp.175-186
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    • 1998
  • The purpose of this research was to investigate effects of Astragali Radix(AR) and Armeniacae Semen(AS) on T-lymphocytes and peritoneal macrophages in mice. The proliferation of thymocytes and splenocytes were teated using macroplate-reader. The apoptosis and sub-population of T-lymphocytes were tested using a flow cytometer. Nitric oxide production was tested using a Griess reagents. The result were obtained as follow; 1. AR increased the proliferation of thymocytes and splenocytes. 2. AS decreased the proliferation of thymocytes and splenocytes. 3. AR and AS decreased No production fron peritoneal macrophages 4. AR and AS were accelerate T-lymphocytes apoptosis. 5. AR and AS increased $T_C$ cells population, but decreased $T_H$ cells population of T-lymphocyte.

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Coherent Forecasting in Binomial AR(p) Model

  • Kim, Hee-Young;Park, You-Sung
    • Communications for Statistical Applications and Methods
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    • v.17 no.1
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    • pp.27-37
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    • 2010
  • This article concerns the forecasting in binomial AR(p) models which is proposed by Wei$\ss$ (2009b) for time series of binomial counts. Our method extends to binomial AR(p) models a recent result by Jung and Tremayne (2006) for integer-valued autoregressive model of second order, INAR(2), with simple Poisson innovations. Forecasts are produced by conditional median which gives 'coherent' forecasts, and we estimate the forecast distributions of future values of binomial AR(p) models by means of a Monte Carlo method allowing for parameter uncertainty. Model parameters are estimated by the method of moments and estimated standard errors are calculated by means of block of block bootstrap. The method is fitted to log data set used in Wei$\ss$ (2009b).

Atomic Layer Etching of Silicon Using a Ar Neutral Beam of Low Energy (저에너지의 Ar 중성빔을 이용한 Silicon의 Atomic Layer Etching)

  • Oh, Chang-Kwon;Park, Sang-Duk;Yeom, Geun-Young
    • Korean Journal of Materials Research
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    • v.16 no.4
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    • pp.213-217
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    • 2006
  • In this study, atomic layer etching of Si has been carried out using $Cl_2$ adsorption followed by the irradiation Ar neutral beam of low energy. In this experiment, the etch rate of Si was dependent on the $Cl_2$ pressure(the surface coverage of chlorine) and the irradiation time of Ar neutral beam(the flux density of Ar neural beam). And the etch rate of Si(100) and Si(111) were saturated exactly at one monolayer per cycle with $1.36{\AA}/cycle\;and\;1.57{\AA}/cycle$, respectively.

Stationary Bootstrapping for the Nonparametric AR-ARCH Model

  • Shin, Dong Wan;Hwang, Eunju
    • Communications for Statistical Applications and Methods
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    • v.22 no.5
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    • pp.463-473
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    • 2015
  • We consider a nonparametric AR(1) model with nonparametric ARCH(1) errors. In order to estimate the unknown function of the ARCH part, we apply the stationary bootstrap procedure, which is characterized by geometrically distributed random length of bootstrap blocks and has the advantage of capturing the dependence structure of the original data. The proposed method is composed of four steps: the first step estimates the AR part by a typical kernel smoothing to calculate AR residuals, the second step estimates the ARCH part via the Nadaraya-Watson kernel from the AR residuals to compute ARCH residuals, the third step applies the stationary bootstrap procedure to the ARCH residuals, and the fourth step defines the stationary bootstrapped Nadaraya-Watson estimator for the ARCH function with the stationary bootstrapped residuals. We prove the asymptotic validity of the stationary bootstrap estimator for the unknown ARCH function by showing the same limiting distribution as the Nadaraya-Watson estimator in the second step.

The development of an augmented reality prototype in dental practice management (치과의료관리 영역에서 증강현실의 프로토타입 개발)

  • Park, Seon Gyu;Lee, Jongki
    • Journal of Korean Academy of Dental Administration
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    • v.8 no.1
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    • pp.24-29
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    • 2020
  • With the advancement of information technology, the application of augmented reality (AR) in dentistry is an emerging research field of image-guided surgery and dental education. In addition, the digital approach to incorporating AR in dental practice management is considered to be feasible. A prototype is developed to apply AR to dental daily clinical practice in order to help dentists to access electronic dental records. This prototype delivers patients' information and related clinical data to dental clinicians directly without the need to search for the appropriate patients. Wearable AR devices are considered to be a convenient tool for practicing dentists because dental practitioners are not always able to use a computer during active clinical sessions, such as implant placement, root canal treatment, and patient-doctor communication. The use of AR to visualize passive transferred patient data would be valuable for practicing dentists.