• 제목/요약/키워드: psi function

검색결과 172건 처리시간 0.026초

Quasi-Cyclic Low Density Panty Check 복호기의 다양한 설계 관점에 대한 성능분석 (Performance Analysis on Various Design Issues of Quasi-Cyclic Low Density Parity Check Decoder)

  • 정수경;박태근
    • 대한전자공학회논문지SD
    • /
    • 제46권11호
    • /
    • pp.92-100
    • /
    • 2009
  • 본 논문은 LLR-BP 복호 알고리즘을 사용하는 LDPC 복호기의 하드웨어 구조 분석하고 효율적인 복호기의 설계 방법들을 제시하였다. 또한 설계 시 복호 성능 및 하드웨어 복잡도에 영향을 미칠 수 있는 다양한 설계 이슈들을 제시하고 복호 성능의 변화를 모의실험을 통하여 분석하였다. 오류확률을 전달하는 메시지의 양자화는 정수부 3비트, 소수부 4비트를 할당하였고, 복호 성능이 저하되지 않도록 사전정보에 정수부 2비트, 소수부 4비트를 할당하였으며 LUT로 구현되는 $\Psi$(x) 함수를 조합회로인 PWL 블록으로 대체하여 하드웨어 구조의 개선에 대해 논의하였다. 복호 시간을 단축하기 위하여 중첩 스케줄링을 적용하고, 각 복호기 구조 및 설계 변수들의 제한에 따른 하드웨어 자원을 비교함으로써, 하드웨어 복잡도를 분석하였다.

The first insight into the structure of the Photosystem II reaction centre complex at $6{\AA}$ resolution determined by electron crystallography

  • Rhee, Kyong-Hi
    • 한국식물학회:학술대회논문집
    • /
    • 한국식물학회 1999년도 Proceedings of the 17th Symposium on Plant Biology Environmental Stress and Photosynthesis
    • /
    • pp.83-90
    • /
    • 1999
  • Electron crystallography of two-dimensional crystalsand electron cryo-microscopy is becoming an established method for determining the structure and function of a variety of membrane proteins that are providing difficult to crystallize in three dimension. In this study this technique has been used to investigate the structure of a ~160 kDa reaction centre sub-core complex of photosystem II. Photosystem II is a photosynthetic membrane protein consisting of more than 25 subunits. It uses solar energy to split water releasing molecular oxygen into the atmosphere and creates electrochemical potential across the thylakoid membrane, which is eventually utilized to generate ATP and NADPH. Images were taken using Philips CM200 field emission gun electron microscope with an acceleration voltage of 200kW at liquid nitrogen temperature. In total, 79 images recorded dat tilt angles ranging from 0 to 67 degree yielded amplitudes and phases for a three-dimensional map with an in-plant resolution of 6$\AA$ and 11.4$\AA$ in the third dimension shows at least 23 transmembrane helices resolved in a monomeric complex, of which 18 were able to be assigned to the D1, D2, CP47 , and cytochrome b559 alfa beta-subunits with their associated pigments that ae active in electron transport (Rhee, 1998, Ph.D.thesis). The D1/D2 heterodimer is located in the central position within the complex and its helical scalffold is remarkably similar to that of the reaction centres not only in purple bacteria but also in plant photosystem I (PSI) , indicating a common evoluationary origin of all types of reaction centre in photosynthetic organism known today 9RHee et al. 1998). The structural homology is now extended to the inner antenna subunit, ascribed to CP47 in our map, where the 6 transmembrane helices show a striking structural similarity to the corresponding helices of the PSI reaction centre proteins. The overall arrangement of the chlorophylls in the D1 /D2 heterodimer, and in particular the distance between the central pair, is ocnsistent with the weak exciton coupling of P680 that distinguishes this reaction centre from bacterial counterpart. The map in most progress towards high resolution structure will be presented and discussed.

  • PDF

초등학생 어머니의 성격유형에 따른 양육태도 및 양육스트레스 (A Study on Parenting Attitude and Stress according to Personality Type in Elementary School Students' Mothers)

  • 고효정;권윤희;김민영
    • 지역사회간호학회지
    • /
    • 제20권2호
    • /
    • pp.215-224
    • /
    • 2009
  • Purpose: This study was performed to examine parenting attitude and stress according to personality type in elementary school students' mothers. Methods: The subjects consisted of 206 mothers of students. The measurement instrument was the questionnaire consisting of Korean-version MBTI and PSI test. Data was collected from March 15th to April 15th, 2008. Results: Among personality types by function, ST type was most, occupying 60.2%. Among personality types by temperament, SJ type was most, occupying 59.2%. The score of affective attitude was highest among the parenting attitudes. Parenting attitude was significantly different according to age, education, economic status, number of children, planned pregnancy, factor of stress, and family type. Parenting stress was significantly different according to planned pregnancy and factor of stress. In parenting attitudes by personality types, affective attitude was significantly different. Parenting stress was significantly different according to personality type by function. There was a negative correlation between affective and autonomic attitudes and parenting stress. There was a positive correlation between rejective attitude and parenting stress. Conclusion: It would be essential to provide dynamic developmental programs for increasing the children's social ability, and nursing intervention, education and counseling programs for decreasing parenting stress through understanding mothers' personality type.

  • PDF

FIXED POINT THEOREMS FOR WEAK CONTRACTION IN INTUITIONISTIC FUZZY METRIC SPACE

  • Vats, Ramesh Kumar;Grewal, Manju
    • 호남수학학술지
    • /
    • 제38권2호
    • /
    • pp.337-357
    • /
    • 2016
  • The notion of weak contraction in intuitionistic fuzzy metric space is well known and its study is well entrenched in the literature. This paper introduces the notion of (${\psi},{\alpha},{\beta}$)-weak contraction in intuitionistic fuzzy metric space. In this contrast, we prove certain coincidence point results in partially ordered intuitionistic fuzzy metric spaces for functions which satisfy a certain inequality involving three control functions. In the course of investigation, we found that by imposing some additional conditions on the mappings, coincidence point turns out to be a fixed point. Moreover, we establish a theorem as an application of our results.

Fractional Diffusion Equation Approach to the Anomalous Diffusion on Fractal Lattices

  • Huh, Dann;Lee, Jin-Uk;Lee, Sang-Youb
    • Bulletin of the Korean Chemical Society
    • /
    • 제26권11호
    • /
    • pp.1723-1727
    • /
    • 2005
  • A generalized fractional diffusion equation (FDE) is presented, which describes the time-evolution of the spatial distribution of a particle performing continuous time random walk (CTRW) on a fractal lattice. For a case corresponding to the CTRW with waiting time distribution that behaves as $\psi(t) \sim (t) ^{-(\alpha+1)}$, the FDE is solved to give analytic expressions for the Green’s function and the mean squared displacement (MSD). In agreement with the previous work of Blumen et al. [Phys. Rev. Lett. 1984, 53, 1301], the time-dependence of MSD is found to be given as < $r^2(t)$ > ~ $t ^{2\alpha/dw}$, where $d_w$ is the walk dimension of the given fractal. A Monte-Carlo simulation is also performed to evaluate the range of applicability of the proposed FDE.

Study of Hydrodynamic-Magnetic-Thermal Coupling in a Linear Induction MHD Pump

  • Kadid, Fatima Zohra;Drid, Said;Abdessemed, Rachid
    • Journal of Electrical Engineering and Technology
    • /
    • 제4권2호
    • /
    • pp.249-254
    • /
    • 2009
  • This article deals with the analysis of a coupling between stationary Maxwell's equations, the transient state Navier-Stokes and thermal equations. The resolution of these equations is obtained by introducing the magnetic vector potential A, the vorticity ${\xi}$, the stream function ${\psi}$ and the temperature T. The flux density, the electromagnetic thrust, the electric power density, the velocity, the pressure and the temperature are graphically visualized. Also, the influence of the frequency is presented.

Negative Exponential Disparity Based Robust Estimates of Ordered Means in Normal Models

  • Bhattacharya, Bhaskar;Sarkar, Sahadeb;Jeong, Dong-Bin
    • Communications for Statistical Applications and Methods
    • /
    • 제7권2호
    • /
    • pp.371-383
    • /
    • 2000
  • Lindsay (1994) and Basu et al (1997) show that another density-based distance called the negative exponential disparity (NED) is an excellent competitor to the Hellinger distance (HD) in generating an asymptotically fully efficient and robust estimator. Bhattacharya and Basu (1996) consider estimation of the locations of several normal populations when an order relation between them is known to be true. They empirically show that the robust HD based weighted likelihood estimators compare favorably with the M-estimators based on Huber's $\psi$ function, the Gastworth estimator, and the trimmed mean estimator. In this paper we investigate the performance of the weighted likelihood estimator based on the NED as a robust alternative relative to that based on the HD. The NED based estimator is found to be quite competitive in the settings considered by Bhattacharya and Basu.

  • PDF

조화분포하중을 받는 원환보의 음향방사 (Sound radiation of curved beam under the action of harmonic line forces)

  • 지창헌
    • 한국안전학회지
    • /
    • 제12권3호
    • /
    • pp.10-16
    • /
    • 1997
  • The problem of sound radiation from curved beam under the action of harmonic line forces is studied. The reaction due to fluid loading on the vibratory response of the curved beam is taken into account. The curved beam is assumed to occupy the plane y=0. The curved beam material and the elastic foundation are assumed to be lossless including a tension force(T), damping coefficient(C) and stiffness of foundation($k_s$) will be employed. The non-dimensional sound power is derived through integration of the surface intensity distribution over the entire curved beam. The expression for sound power is integrated numerically and the results are examined as a function of wavenumber ratio($\gamma$) and stiffness factor($\psi$).

  • PDF

NEW COMPLEXITY ANALYSIS OF PRIMAL-DUAL IMPS FOR P* LAPS BASED ON LARGE UPDATES

  • Cho, Gyeong-Mi;Kim, Min-Kyung
    • 대한수학회보
    • /
    • 제46권3호
    • /
    • pp.521-534
    • /
    • 2009
  • In this paper we present new large-update primal-dual interior point algorithms for $P_*$ linear complementarity problems(LAPS) based on a class of kernel functions, ${\psi}(t)={\frac{t^{p+1}-1}{p+1}}+{\frac{1}{\sigma}}(e^{{\sigma}(1-t)}-1)$, p $\in$ [0, 1], ${\sigma}{\geq}1$. It is the first to use this class of kernel functions in the complexity analysis of interior point method(IPM) for $P_*$ LAPS. We showed that if a strictly feasible starting point is available, then new large-update primal-dual interior point algorithms for $P_*$ LAPS have $O((1+2+\kappa)n^{{\frac{1}{p+1}}}lognlog{\frac{n}{\varepsilon}})$ complexity bound. When p = 1, we have $O((1+2\kappa)\sqrt{n}lognlog\frac{n}{\varepsilon})$ complexity which is so far the best known complexity for large-update methods.

채널의 경사각이 전자부품의 열적 안정성에 미치는 영향 (Effects of the Inclined Angles of Channel on Thermal Stability of Electronic Components)

  • 추홍록;상희선;유재환
    • 한국안전학회지
    • /
    • 제15권1호
    • /
    • pp.36-42
    • /
    • 2000
  • An experimental study was carried out to investigate the effects of inclined angles of channel on thermal stability of electronic components. In this study, it is focused on the natural convection heat transfer from an inclined parallel channel with discrete protruding heat sources. The material used for the inclined parallel channel was epoxy-resin, while air as the cooling fluid. Heat transfer phenomena for inclined angles of $\psi$=$15^{\circ}$, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$ and for the range of $9.52{\times}10^5/ were analyzed. The thermal fields in the channel were visualized by Mach-Zehnder interferometer. Also, local temperatures were measured by thermocouples along the channel wall and heat sources surface. As a result, for the range of $4.29{\times} 10^5/, a useful correlation of mean Nusselt number was proposed as a function of modified channel Rayleigh number.

  • PDF