• Title/Summary/Keyword: ${\alpha}$-limit

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Eclipse Spectrum of Her X-1 Observed by ASCA in the Low Intensity State

  • Choi, C.S.;Seon, K.I.
    • Bulletin of the Korean Space Science Society
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    • 1995.10a
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    • pp.30-30
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    • 1995
  • We present the results of analysis on the X-ray observations of the binary X-ray pulsar Her X-I. made with ASCA/SIS on August 13-14. 1993. An eclipse transition from ingress to egress was fully covered by the observations. The main findings are as follows; (1) a model of power-law plus black-body is required to interpret the entire eclipse spectrum. and the black-body component appears at < 0.7 keV. (2) the power-law continuum which has photon index ${\alpha}\;=\;{0.84^{\;+0.14}}_{\;-0.19}$ is very similar to that of detected by Ginga/LAC (${\alpha}\;=\;0.80\;{\pm}\;0.04$), (3) the calculated eclipse flux of $2^{-10}\;keV.{\;}~{\;}1.8{\pm}10^{-11}{\;}ergs{\;}cm^{-2}s^{-1}$, is consistent with the Ginga observation carried out in the high intensity state ~2.0{\pm}10^{-11}{\;}ergs{\;}cm^{-2}s^{-1}$, (4) there is no significant absorption feature. and an upper limit of the aborption column $NH{\;}\leq{\;}3{\pm}10^{20}\;cm^{-2}$ is determined at the 90% confidence limit. Based on these results, we suggest that extended matter surrounding the binary system should be existed persistently with stable conditions, and scattering of the source continuum by the matter is responsible for the eclipse emission.ission.

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Double-Enhancement Strategy: A Practical Approach to a Femto-Molar Level Detection of Prostate Specific $Antigen-{\alpha}_1-Antichymotrypsin$ (PSA/ACT Complex) for SPR Immunosensing

  • Cao, Cuong;Sim, Sang-Jun
    • Journal of Microbiology and Biotechnology
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    • v.17 no.6
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    • pp.1031-1035
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    • 2007
  • Prostate specific $antigen-{\alpha}_1-antichymotrypsin$ was detected by a double-enhancement strategy involving the exploitation of both colloidal gold nanoparticles (AuNPs) and precipitation of an insoluble product formed by HRP-biocatalyzed oxidation. The AuNPs were synthesized and conjugated with horse-radish peroxidase-PSA polyclonal antibody by physisorption. Using the protein-colloid for SPR-based detection of the PSPJACT complex showed their enhancement as being consistent with other previous studies with regard to AuNPs enhancement, while the enzyme precipitation using DAB substrate was applied for the first time and greatly amplified the signal. The limit of detection was found at as low as 0.027 ng/ml of the PSA/ACT complex (or 300 fM), which is much higher than that of previous reports. This study indicates another way to enhance SPR measurement, and it is generally applicable to other SPR-based immunoassays.

Testing of Poisson Incidence Rate Restriction

  • Singh, Karan;Shanmugam, Ramalingam
    • International Journal of Reliability and Applications
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    • v.2 no.4
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    • pp.263-268
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    • 2001
  • Shanmugam(1991) generalized the Poisson distribution to capture a restriction on the incidence rate $\theta$ (i.e. $\theta$$\beta$, an unknown upper limit), and named it incidence rate restricted Poisson (IRRP) distribution. Using Neyman's C($\alpha$) concept, Shanmugam then devised a hypothesis testing procedure for $\beta$ when $\theta$ remains unknown nuisance parameter. Shanmugam's C ($\alpha$) based .results involve inverse moments which are not easy tools, This article presents an alternate testing procedure based on likelihood ratio concept. It turns out that likelihood ratio test statistic offers more power than the C($\alpha$) test statistic. Numerical examples are included.

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APPLICATIONS OF JACK'S LEMMA FOR CERTAIN SUBCLASSES OF HOLOMORPHIC FUNCTIONS ON THE UNIT DISC

  • Catal, Batuhan;ornek, Bulent Nafi
    • Communications of the Korean Mathematical Society
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    • v.34 no.2
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    • pp.543-555
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    • 2019
  • In this paper, we give some results on ${\frac{zf^{\prime}(z)}{f(z)}}$ for the certain classes of holomorphic functions in the unit disc $E=\{z:{\mid}z{\mid}<1\}$ and on ${\partial}E=\{z:{\mid}z{\mid}=1\}$. For the function $f(z)=z^2+c_3z^3+c_4z^4+{\cdots}$ defined in the unit disc E such that $f(z){\in}{\mathcal{A}}_{\alpha}$, we estimate a modulus of the angular derivative of ${\frac{zf^{\prime}(z)}{f(z)}}$ function at the boundary point b with ${\frac{bf^{\prime}(b)}{f(b)}}=1+{\alpha}$. Moreover, Schwarz lemma for class ${\mathcal{A}}_{\alpha}$ is given. The sharpness of these inequalities is also proved.

Spectrophotometric Determination of Copper After Selective Extraction with $\alpha$-(2-Benzimidazolyl)-$\alpha ^{\prime}, \alpha ^{\prime} ^{\prime}$-(N-5-nitro-2-pyridyl hydrazone)-toluene in the Presence of Brij 58

  • 박찬일;김현수;차기원
    • Bulletin of the Korean Chemical Society
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    • v.20 no.3
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    • pp.352-354
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    • 1999
  • The spectrophotometric determination of Cu(Ⅱ) with α-(2-benzimidazolyl)-α',α"-(N-5-nitro-2-pyridylhydrazone)-toluene has been investigated. The optimum conditions of pH, stability, concentration of ligand and surfactant were evaluated. This method is a simple and sensitive method for determination of Cu(Ⅱ) and offers a selective separation of Cu(Ⅱ) from sample solution containin- I ppm below amount of Ni(Ⅱ), Co(Ⅱ), Zn(Ⅱ) and Sn(Ⅱ). Copper was determined by measuring the absorbance of Cu(Ⅱ)-BINPHT complex extracted with benzene in Brij 58 surfactant at 410 nm. Beer's law is obeyed over the concentration range 0∼2.5 μgmL-1 and the detection limit (S/N=2) is 0.06 μgmL-1. The relative standard deviation at the 0.3 μgmL-1 is 2.4% (N=7). The method was applied for the determination of Cu(Ⅱ) in various milks.

Time dependent heat transfer of proliferation resistant plutonium

  • Lloyd, Cody;Hadimani, Ravi;Goddard, Braden
    • Nuclear Engineering and Technology
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    • v.51 no.2
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    • pp.510-517
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    • 2019
  • Increasing proliferation resistance of plutonium by way of increased $^{238}Pu$ content is of interest to the nuclear nonproliferation and international safeguards community. Considering the high alpha decay heat of $^{238}Pu$, increasing the isotopic fraction leads to a noticeably higher amount of heat generation within the plutonium. High heat generation is especially unattractive in the scenario of weaponization. Upon weaponization of the plutonium, the plutonium may generate enough heat to elevate the temperature in the high explosives to above its self-explosion temperature, rendering the weapon useless. In addition, elevated temperatures will cause thermal expansion in the components of a nuclear explosive device that may produce thermal stresses high enough to produce failure in the materials, reducing the effectiveness of the weapon. Understanding the technical limit of $^{238}Pu$ required to reduce the possibility of weaponization is key to reducing the current limit on safeguarded plutonium (greater than 80 at. % $^{238}Pu$). The plutonium vector evaluated in this study was found by simulating public information on Lightbridge's fuel design for pressurized water reactors. This study explores the temperature profile and maximum stress within a simple (first generation design) hypothetical nuclear explosive device of four unique scenarios over time. Analyzing the transient development of both the temperature profile and maximum stress not only establishes a technical limit on the $^{238}Pu$ content, but also establishes a time limit for which each scenario would be useable.

Ion Effect on Steroid Bioconversion in Rhizopus nigricans (Rhizopus nigricans의 Steroid 전환 반응에 대한 이온의 변화)

  • Lee, Jung-Jin;Kim, Mal-Nam
    • The Korean Journal of Mycology
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    • v.21 no.1
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    • pp.23-27
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    • 1993
  • Ion effects on $11{\alpha}-hydroxylation$ of progesterone and $5{\alpha}-reduction\;of\;11{\alpha}-hydroxyprogesterone$ by Rhizopus nigricans were investigated. Metal ions such as $Cu^{2+},\;Cd^{2+},\;Co^{2+},\;Mn^{2+},\;Zn^{2+},\;Fe^{2+},\;Mg^{2+},\;Fe^{3+}\;and\;Na^+$ reduced the $11{\alpha}-hydroxylation$ activity, while $K^+$ stimulated the same reaction. Enzyme activity for the $5{\alpha}-reduction$ of $11{\alpha}-hydroxyprogesterone$ was increased in the presence of $Fe^{2+},\;Mn^{2+},\;Mg^{2+},\;Co^{2+},\;Zn^{2+},\;Fe^{3+},\;K^+\;and\;Na^+$, whereas it was decreased in the presence of $Cd^{2+}\;and\;Cu^{2+}$. Potassium ion of $10^{-3}\;M\;$ of concentration was found to be effective for the promotion of $11{\alpha}-hydroxylation$. On the other hand, cadmium ion of $10^{-4}\;M$ was proved to suppress the $5{\alpha}-reduction$ reaction. Progesterone is reported to be transformed into $11{\alpha}-hydroxyprogesterone$ which, in turn, is converted further into $11{\alpha}-hydroxy-allopregnane-3$, 20-dione by R. nigricans. From this point of view, the highest yield of $11{\alpha}-hydroxyprogesterone$ could be obtained when potassium ion of $10^{-3}\;M$ was given initially followed by addition of cadmium ion of $10^{-4}\;M$ to limit conversion of 11{\alpha}-hydroxyprogesterone into $11{\alpha}-hydroxy-allopregnane-\;3$, 20-dione.

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Progesterone Hydroxylation by Rhizopus nigricans(I): The effects of reaction conditions (Rhizopus nigricans 에 의한 Progesterone 의 Hydroxylation(I): 반응 조건의 영향)

  • Kim, Myung-Hee;Kim, Mal-Nam
    • The Korean Journal of Mycology
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    • v.15 no.1
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    • pp.23-28
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    • 1987
  • Physicochemical factors influencing the $11{\alpha}$, hydroxylation of progesterone by Rhizopus nigricans Ehrenberg were studied. The higher is the concentration of progesterone. the shorter time is need to attain maximum yield in the $11{\alpha}-hydroxyprogesterone$. High concentration in progesterone was supposed to inhibit the hydroxylation reaction of the $11{\alpha}-hydroxyprogesterone$. The range of optimum pH and temperature appeared to be rather broad and these conditions were similar to those of optimum growth of the mycelia. Agitation at a higher speed than a certain limit, and the presence of sugars accelerated the $11{\alpha}-hydroxyprogesterone$ reaction. Glucose was found to be more effective for the reaction using spores rather than mycelia as enzyme sources. Organic solvents were proved to supress the enzyme activity, which decreased with increase in the concentration of the organic solvents and in the time for pretreatment with the solvents.

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Design of the Robust CV Control Chart using Location Parameter (위치모수를 이용한 로버스트 CV 관리도의 설계)

  • Chun, Dong-Jin;Chung, Young-Bae
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.39 no.1
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    • pp.116-122
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    • 2016
  • Recently, the production cycle in manufacturing process has been getting shorter and different types of product have been produced in the same process line. In this case, the control chart using coefficient of variation would be applicable to the process. The theory that random variables are located in the three times distance of the deviation from mean value is applicable to the control chart that monitor the process in the manufacturing line, when the data of process are changed by the type of normal distribution. It is possible to apply to the control chart of coefficient of variation too. ${\bar{x}}$, s estimates that taken in the coefficient of variation have just used all of the data, but the upper control limit, center line and lower control limit have been settled by the effect of abnormal values, so this control chart could be in trouble of detection ability of the assignable value. The purpose of this study was to present the robust control chart than coefficient of variation control chart in the normal process. To perform this research, the location parameter, ${\bar{x_{\alpha}}}$, $s_{\alpha}$ were used. The robust control chart was named Tim-CV control chart. The result of simulation were summarized as follows; First, P values, the probability to get away from control limit, in Trim-CV control chart were larger than CV control chart in the normal process. Second, ARL values, average run length, in Trim-CV control chart were smaller than CV control chart in the normal process. Particularly, the difference of performance of two control charts was so sure when the change of the process was getting to bigger. Therefore, the Trim-CV control chart proposed in this paper would be more efficient tool than CV control chart in small quantity batch production.

Effect on Body Balance due to Occlusal Biteplane Splint (교합안정장치가 신체 균형에 미치는 영향)

  • Kim, Jeong-Uk;Park, Min-Chull;Choi, Sung-Min;Lee, Sang-Yeol;Won, Hyeon-Jin
    • The Journal of the Korea Contents Association
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    • v.13 no.4
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    • pp.273-280
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    • 2013
  • This study aims to examine the influences of wearing an occlusal biteplane splint on balance of the body. 10 subjects were selected who had neither impaired occlusion and masticating systems nor difficulty in walking along with no medical history in temporomandibular joint. Measurements were conducted with the Fukuda stepping test, the limits of stability test. The level of significance, ${\alpha}$ to determine the statistical significance was .05. Fukuda stepping test and the limits of stability test were put to the Wilcoxon signed test. As a result of this study, there was a significant difference in the moving distance in the Fukuda stepping test (p<.05). In addition, there were significant differences in the results of the limits of stability test (p<.05). In conclusion, the results of this study suggest that wearing the occlusal biteplane splint has an positive influence on the balance of the boby.