• Title/Summary/Keyword: chi parameters ($\chi_{12}$)

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A report of sixteen unrecorded haloarchaea species in Korea, isolated from a solar saltern

  • Chi Young Hwang;Eui-Sang Cho;Dong-Hyun Jung;Ki-Eun Lee;In-Tae Cha;Won-Jae Chi;Myung-Ji Seo
    • Journal of Species Research
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    • v.12 no.spc2
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    • pp.45-53
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    • 2023
  • In July 2018, solar saltern samples were collected from Siheung, Gyeonggi-do Province to obtain unrecorded haloarchaea in Korea. The samples were suspended in a 20% NaCl (w/v) solution, and serial dilution was performed in fresh DB Characterization media No. 2. The strains isolated in this study showed at least 98.7% sequence similarity or more compared to the previously reported. Finally, 16 haloarchaeal strains, which were not reported in Korea but validly published under the International Code of Nomenclature of Prokaryotes (ICNP), were obtained from a solar saltern in Siheung. These 16 isolates were allocated to the orders Halobacteriales and Haloferacales. The 10 Halobacteriales strains were classified into the family Halobacteriaceae and Haloarculaceae. Each family belonged to three genera, respectively. The other six Haloferacales belonged to the families Haloferacaceae and Halorubraceae. Each family belonged to genus genus, respectively. Collectively, the unrecorded haloarchaeal strains belonged to two orders, four families, and eight genera. During the research, the possibility of discovering previously unknown species in domestic solar saltern was established. Gram-staining, cell morphology, physiological and basic biochemical parameters, and phylogenetic analysis were all performed in this study and are described in detail for each strain.

A Study on the Test of Homogeneity for Nonlinear Time Series Panel Data Using Bilinear Models (중선형 모형을 이용한 비선형 시계열 패널자료의 동질성검정에 대한 연구)

  • Kim, Inkyu
    • Journal of Digital Convergence
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    • v.12 no.7
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    • pp.261-266
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    • 2014
  • When the number of parameters in the time series model are diverse, it is hard to forecast because of the increasing error by a parameter estimation. If the homogeneity hypothesis which was obtained from the same model about severeal data for the time series is selected, it is easy to get the predictive value better. Nonlinear time-series panel data for each parameter for each time series, since there are so many parameters that are present, and the large number of parameters according to the parameter estimation error increases the accuracy of the forecast deteriorated. Panel present in the time series of multiple independent homogeneity is satisfied by a comprehensive time series to estimate and to test of the parameters. For studying about the homogeneity test for the m independent non-linear of the time series panel data, it needs to set the model and to make the normal conditions for the model, and to derive the homogeneity test statistic. Finally, it shows to obtain the limit distribution according to ${\chi}^2$ distribution. In actual analysis,, we can examine the result for the homogeneity test about nonlinear time series panel data which are 2 groups of stock price data.

Thermal Emissivity of Nuclear Graphite as a Function of its Oxidation Degree (3): Structural Study using Scanning Electron Microscope and X-Ray Diffraction

  • Seo, Seung-Kuk;Roh, Jae-Seung;Kim, Suk-Hwan;Chi, Se-Hwan;Kim, Eung-Seon
    • Carbon letters
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    • v.12 no.1
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    • pp.8-15
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    • 2011
  • We study the relationships between the thermal emissivity of nuclear graphites (IG-110, PCEA, IG-430 and NBG-18) and their surface structural change by oxidation using scanning electron microscope and X-ray diffraction (XRD). The nonoxidized (0% weight loss) specimen had the surface covered with glassy materials and the 5% and 10% oxidized specimens, however, showed high roughness of the surface without glassy materials. During oxidation the binder materials were oxidized first and then graphitic filler particles were subsequently oxidized. The 002 interlayer spacings of the non-oxidized and the oxidized specimens were about $3.38{\sim}3.39{\AA}$. There was a slight change in crystallite size after oxidation compared to the nonoxidized specimens. It was difficult to find a relationship between the thermal emissivity and the structural parameters obtained from the XRD analysis.

ON ESTIMATION OF NEGATIVE POLYA-EGGENBERGER DISTRIBUTION AND ITS APPLICATIONS

  • Hassan, Anwar;Bilal, Sheikh
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.12 no.2
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    • pp.81-95
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    • 2008
  • In this paper, the negative Polya-Eggenberger distribution has been introduced by compounding negative binomial distribution with beta distribution of I-kind which generates a number of univariate contagious or compound (or mixture of) distributions as its particular cases. The distribution is unimode, over dispersed and all of its positive and negative integer moments exist. The difference equation of the proposed model shows that it is a member of the Ord's family of distribution. Some of its interesting properties have been explored besides different methods of estimation been discussed. Finally, the parameters of the proposed model have been estimated by using a computer programme in R-software. Application of the proposed model to some data, available in the literature, has been given and its goodness of fit demonstrated.

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Optimal Culture Conditions for Mycelial Growth and Exo-polymer Production of Ganoderma applanatum

  • Jeong, Yong-Tae;Jeong, Sang-Chul;Yang, Byung-Keun;Islam, Rezuanul;Song, Chi-Hyun
    • Mycobiology
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    • v.37 no.2
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    • pp.89-93
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    • 2009
  • The effect of fermentation parameters and medium composition on the simultaneous mycelial growth and exo-polymer production from submerged cultures of Ganoderma applanatum was investigated in shake-flask cultures. The optimum initial pH for mycelial growth and exo-polymer production was 5.0 and 6.0, respectively. The optimum temperature was $25^{\circ}C$ and the optimum inoculum content was 3.0% (v/v). The optimal carbon and nitrogen sources were glucose and corn steep powder, respectively. After 12 days fermentation under these conditions, the highest mycelial growth was 18.0 g/l and the highest exo-polymer production was 3.9 g/l.

Optimization of Synthetic Parameters for Mesoporous Molecular Sieve MCM-41 Using Surfactant CTAC1

  • 박동호;Cheng, Chi Feng;Jacek Klinowski
    • Bulletin of the Korean Chemical Society
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    • v.18 no.4
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    • pp.379-384
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    • 1997
  • High quality MCM-41 is prepared from a gel of molar composition SiO2:0.20 CTACl:0.18 TMAOH:25 H2O aged at 20 ℃ for 24 hours before crystallization lasting for 48 hours. The (110) and (200) peaks of XRD pattern of high quality MCM-41 are unusually well resolved and the FWHM (full-width-at-half-maximum) of the (100) peak is 0.13° for as-prepared MCM-41 and 0.21° for calcined one, which indicate well-developed crystals. The properties of the crystal depend on the source and concentration of the reactants and the gel aging time. There is no induction period in the course of the synthesis, which is conveniently monitored by pH measurement. Gel aging, during which a spatial distribution of silicate polyanions and micellar cations is established, is essential for preparing high quality MCM-41. Surfactants with the same cationic organic group but different counteranions change the crystallization behavior. Highly basic gel (pH=12.6) favours the lamellar product; the quality of MCM-41 is lower as insufficient TMAOH is available to dissolve the silica.

Genetic parameters and litter trait trends of Danish pigs in South Vietnam

  • Tinh, Nguyen Huu;Hao, Tran Van;Bui, Anh Phu Nam
    • Animal Bioscience
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    • v.34 no.12
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    • pp.1903-1911
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    • 2021
  • Objective: The objective of this study was to estimate the genetic parameters and various litter trait trends of Danish pigs in South Vietnam, including the number born alive (NBA), number weaned (NW), and litter weight at the 21st day (LW21). Methods: Records of 936 Yorkshire sows with 3361 litters and 973 Landrace sows with 3161 litters were used to estimate the variance components, genetic parameters, and trends of NBA, NW, and LW21. The restricted maximum likelihood method was applied using VCE6 software to obtain the variance components and genetic parameters. Thereafter, the best linear unbiased prediction procedure with an animal model was applied using PEST software to estimate the breeding values of the studied traits. Results: The heritability estimates were low, ranging from 0.12 to 0.21 for NBA, 0.03 to 0.04 for NW, and from 0.11 to 0.13 for LW21. The genetic correlation between the NBA and NW was relatively strong in both breeds, at 0.77 and 0.60 for Yorkshire and Landrace, respectively. Similarly, the genetic correlation between the NW and LW21 was considerably stronger in Landrace pigs (0.71) than in Yorkshire pigs (0.48). The estimates of annual genetic progress were 0.0431, 0.0233, and 0.0461 for NBA, NW, and LW21 in Landrace pigs and 0434, 0.0202, and 0.0667 for NBA, NW, and LW21 in Yorkshire pigs, respectively. Conclusion: The positive genetic trends estimated for the additive genetic values of the selected traits indicated that the current breeding system has achieved favorable results.

A Study of the Prosodic Characteristics of Homographs with Context Cues by Subjects with Right and Left Hemisphere Damage (문맥 내에서 좌우반구 손상자의 동음어에 대한 운율 산출 비교)

  • Lee, Myoung-Soon
    • Phonetics and Speech Sciences
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    • v.2 no.1
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    • pp.13-21
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    • 2010
  • The purpose of this study was to examine the prosody characteristics of sentence-level utterances which contain homographs with context cues in patients with neurogenic communication disorders. Homographs which may be affected by prosody, especially tonic length features, were used to investigate this matter. The characteristics of tone, duration, pitch, and pitch peak were analyzed to examine the characteristics of prosody in patients with lesions in the left or right hemisphere and normal controls. The whole process was recorded using Praat 4.3.14 and for statistical analyses, three-way ANOVA and multiple comparative analyses, Chi-Square tests, and a one-way ANOVA were carried out using SPSS 12.0 for Windows. The conclusions of this study are as follows. First, the length of syllables and vowels in homographs in Korean was different depending on the meaning and was not significant between groups. Second, it was found that patients with lesions in the right hemisphere had significant difference on pitch. Third, it was found that frequency of pitch peak and tone in 'short' tone syllables were different between groups. The conclusion of this study found that the prosody of homographs between groups absolutely was not differentiated. Accordingly, more detailed studies of acoustic parameters and other parameters which the prosody characteristic between groups could be found are needed in the future.

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A Study on the Real Time Digital Field Time-Constant Regulator for Micro-Synchronous Machine (축소형 동기발전기 실시간 디지털 계자시정수 보상장치에 관한 연구)

  • Kim, Dong-Joon;Moon, Young-Hwan;Hwang, Chi-U
    • Proceedings of the KIEE Conference
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    • 1997.11a
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    • pp.253-256
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    • 1997
  • This paper describes a novel design method for compensating field time-constant of micro-synchronous machine so that its terminal flux can show the same characteristics as large-scale synchronous machine's. In addition to it, the suggested design method can determine the field time-constant regulator's parameters considered the nonlinearities of micro-synchronous machine such as saturation and loading effect. This method applied to 5kVA micro-synchronous machine, and the digital time-constant regulator with digital AVR were designed such that the short field time-constant, $T_{do}'=1.12\;sec$, can take on the large-scale synchronous machine time constant, $T_{do}'=1.47\;sec$. After determining the parameters of controllers, the real time digital time-constant regulator and digital AVR algorithm were implemented by using the PC with Penumum processor, and the usefulness of suggested real time digital time-constant regulator was verified by observing its good performance on the excitation of micro-synchronous machine.

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The study for improvement performance to be alteration packet type on multi-buffer scheme in wireless lan Here (초고속무선통신 기반의 멀티버퍼 패킷구조 변경에 따른 성능 향상에 관한 연구)

  • Park, Chi-Ho;Oh, Young-Hwan
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.42 no.12
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    • pp.95-102
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    • 2005
  • This paper is purpose for improvement performance wireless lan of IEEE802.11a/b/g. Access point utilized a single server, multi-queuing system, FIFS system model to adapted priority multi-bufferto be alteration packet type. The main purpose of the paper improve the transmission rate and the performance of access point to settle transmission delay for load in MAC, has priority multi-buffer. We use experimentation to obtain our model of the access point and buffer-related parameters. Using our test design, we are able to extract the parameters of an analytic equation giving the average service time of a packet as a function of packer IP payload.