• Title/Summary/Keyword: various function

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Mid-Infrared Luminosity Function of Local Galaxies in the North Ecliptic Pole Region

  • Kim, Seong-Jin;Lee, Hyeong-Mok
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.38.1-38.1
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    • 2013
  • We present observational estimation of the infrared (IR) luminosity function (LF) of local (z < 0.3) star-forming (SF) galaxies derived from the AKARI NEP-Wide samples. We made an analysis of the NEP-Wide data with optical spectroscopic information allowing an accurate determination of luminosity function. Spectroscopic redshifts for about 1650 objects were obtained with MMT/Hectospec and WIYN/Hydra, and the median redshifts is about 0.22. To measure the contribution of SF galaxies to the luminosity function, we excluded AGN sample by comparing their SEDs with various model template. Spectroscopic redshifts and the AKARI's continuous filter coverage in the mid-IR (MIR) wavelength (2 ~ 25 micron) enable us to avoid large uncertainties from the mid-IR SED of galaxies and corresponding k-corrections. The 8-micron luminosity function shows a good agreement with the previous works in the bright-end, whereas it seems not easy to constrain the faint-end slope. The comparison with the results of the NEP-Deep data (Goto et al. 2010) suggests the luminosity evolution to the higher redshifts, which is consistent with the down-sizing evolutionary pattern of galaxies.

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Noninformative priors for linear function of parameters in the lognormal distribution

  • Lee, Woo Dong;Kim, Dal Ho;Kang, Sang Gil
    • Journal of the Korean Data and Information Science Society
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    • v.27 no.4
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    • pp.1091-1100
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    • 2016
  • This paper considers the noninformative priors for the linear function of parameters in the lognormal distribution. The lognormal distribution is applied in the various areas, such as occupational health research, environmental science, monetary units, etc. The linear function of parameters in the lognormal distribution includes the expectation, median and mode of the lognormal distribution. Thus we derive the probability matching priors and the reference priors for the linear function of parameters. Then we reveal that the derived reference priors do not satisfy a first order matching criterion. Under the general priors including the derived noninformative priors, we check the proper condition of the posterior distribution. Some numerical study under the developed priors is performed and real examples are illustrated.

A Current Differential Relay for Transformer Protection with a Blocking Method Using the Difference-Function of a Differential Current (차전류 차분 블로킹 변압기 보호용 전류차동 계전기)

  • 강용철;원성호;김대성;양성채
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.12
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    • pp.691-697
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    • 2003
  • This paper proposes a current differential relay for transformer protection that operates in accordance with a blocking method based on the difference-function of a differential current. For magnetic inrush and over-excitation, discontinuities in the first-difference function of the differential current arise at the points of inflection, which correspond to the start and end of each saturation period of the core. These discontinuities are converted into the pulses in the second- and third-difference functions of the differential current. The magnitudes of the pulses are large enough to detect saturation of the core. A blocking signal is issued if the magnitude of the third-difference function exceeds the threshold and is maintained for three quarters of a cycle. The performance of the relay is assessed under various conditions with magnetic inrush, internal faults and external faults. The proposed blocking method can improve significantly the operating time of a relay and achieve high sensitivity of a relay.

CERTAIN RESULTS ON EXTENDED GENERALIZED τ-GAUSS HYPERGEOMETRIC FUNCTION

  • Kumar, Dinesh;Gupta, Rajeev Kumar;Shaktawat, Bhupender Singh
    • Honam Mathematical Journal
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    • v.38 no.4
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    • pp.739-752
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    • 2016
  • The main aim of this paper is to introduce an extension of the generalized ${\tau}$-Gauss hypergeometric function $_rF^{\tau}_s(z)$ and investigate various properties of the new function such as integral representations, derivative formulas, Laplace transform, Mellin trans-form and fractional calculus operators. Some of the interesting special cases of our main results have been discussed.

An endochronic model of material function and its application to plastic behavior of metals under asymmetric cyclic loadings

  • Yeh, Wei-Ching;Lin, Hsi-Yen;Jhaot, Jhen-Bo
    • Structural Engineering and Mechanics
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    • v.25 no.4
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    • pp.423-444
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    • 2007
  • By using the incremental form of the endochronic theory of plasticity, a model of material function is proposed in this paper to investigate plastic behavior. By comparing the stress-strain hysteresis loop, the theory is shown to agree well with the experimental results, especially in the evolution of peak stress values of SAE 4340 steel loaded by cyclic loading with various amplitudes. Depending on the choice of material parameters, the present model can substantially result in six categories of material function, each of which can behave differently with respect to an identical deformation history. In addition, the present model of material function is shown to be capable of describing the behavior of erasure of memory of materials, as experimentally observed by Lamba and Sidebottom (1978).

Clinical Appliance of Structure-Function Studies of Salivary Macromolecules (타액 단백질의 기능 및 구조 연구의 임상적 적용)

  • 고홍섭
    • Journal of Oral Medicine and Pain
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    • v.23 no.3
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    • pp.241-247
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    • 1998
  • Salivary research is at a critical crossroads regarding the clinical application of the basic knowledge. The purpose of this article is to introduce the current progress on salivary research to Korean dental scientists. The accumulated results based on advance technologies such as protein chemistry, molecular biology, and structural biology have showed that salivary macromolecules need structural requirements for proper function. Currently, several concepts or principles, which can be applied to salivary macromolecules, have been suggested. These include the role of molecules' conformation on biological activity, their multifunctional nature, their redundancy of function, their amphifunctional properties, and the potential importance of complexing between molecules. These concepts and the information available will help the development of saliva substitutes, the design of drug carriers and chimera molecules with enhanced function and the development of gene therapy protocols. These approaches will alleviate or restore lost salivary function and can be used to treat various kinds of oral and systemic diseases.

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Implementing Framework for Transfer Function-based Ship Underwater Radiated Noise Analysis (전달함수 기반의 선박 수중방사소음 해석 프레임워크 구현)

  • Kim, Kook-Hyun
    • Journal of the Society of Naval Architects of Korea
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    • v.47 no.6
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    • pp.803-807
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    • 2010
  • The transfer function method is a widely used in the analysis of underwater radiated noise of ships because it is simple to implement and gives a simple way in the design stage requiring trade-off studies on various kinds of noise sources. In this study, a framework is implemented based on the transfer function method. The framework is interfaced to a software providing transfer functions of hull force to underwater radiated noise. The transfer function-based underwater radiated noise analysis approach is reviewed and the implemented framework structure is described. As an example, a numerical calculation of a virtual ship is carried out and its results are investigated in terms of applicability to real ship design project.

A Study on Radar Waveform - Polyphase Sequence (레이더 파형 연구 - 다위상 시퀀스)

  • Yang, Jin-Mo;Kim, Whan-Woo
    • Journal of the Korea Institute of Military Science and Technology
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    • v.13 no.4
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    • pp.673-682
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    • 2010
  • This paper describes and analyzes a various generation methods of the mutually orthogonal polyphase sequences with low cross-correlation peak sidelobe and low autocorrelation peak sidelobe levels. The mutual orthogonality is the key requirement of multi-static or MIMO(Multi-Input Multi-Output) radar systems which provides the good target detection and tracking performance. The polyphase sequences, which are generated by SA(Simulated Annealing) and GA(Genetic Algorithm), have been analyzed with ACF(Autocorrelation Function) PSL(Peak Sidelobe Level) and CCF(Crosscorrelation Function) level at the matched filter output. Also, the ambiguity function has been introduced and simulated for comparing Doppler properties of each sequence. We have suggested the phase selection rule for applying multi-static or MIMO systems.

Development of GPS game machine of space and a position information system

  • Lee, Dae-Young;Park, Kil-Hwan;Bae, Sang-Hyun
    • Proceedings of the KAIS Fall Conference
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    • 2003.11a
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    • pp.243-246
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    • 2003
  • This system is unionized form about GPS and a pocket game machine. This game machine of the use only for the game with an existing system but the function of various purposes which carries out service relevant to a user's position information. This system have the game function, the function to offer space guidance service by the theme interlocked with a user's position, and the traffic safety education function.

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Development of Portable Conversation-Type English Leaner (대화식 휴대용 영어학습기 개발)

  • Yoo, Jae-Tack;Yoon, Tae-Seob
    • Proceedings of the KIEE Conference
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    • 2004.05a
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    • pp.147-149
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    • 2004
  • Although most of the people have studied English for a long time, their English conversation capability is low. When we provide them portable conversational-type English learners by the application of computer and information process technology, such portable learners can be used to enhance their English conversation capability by their conventional conversation exercises. The core technology to develop such learner is the development of a voice recognition and synthesis module under an embedded environment. This paper deals with voice recognition and synthesis, prototype of the learner module using a DSP(Digital Signal Processing) chip for voice processing, voice playback function, flash memory file system, PC download function using USB ports, English conversation text function by the use of SMC(Smart Media Card) flash memory, LCD display function, MP3 music listening function, etc. Application areas of the prototype equipped with such various functions are vast, i.e. portable language learners, amusement devices, kids toy, control by voice, security by the use of voice, etc.

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