• Title/Summary/Keyword: IOTA

Search Result 165, Processing Time 0.028 seconds

Enhancing seismic reflection signal (탄성파 반사 신호 향상)

  • Hien, D.H.;Jang, Seong-Hyung;Kim, Young-Wan;Suh, Sang-Yong
    • 한국신재생에너지학회:학술대회논문집
    • /
    • 2008.05a
    • /
    • pp.606-609
    • /
    • 2008
  • Deconvolution is one of the most used techniques for processing seismic reflection data. It is applied to improve temporal resolution by wavelet shaping and removal of short period reverberations. Several deconvolution algorithms such as predicted, spike, minimum entropy deconvolution and so on has been proposed to obtain such above purposes. Among of them, $\iota_1$ norm proposed by Taylor et al., (1979) and used to compared to minimum entropy deconvolution by Sacchi et al., (1994) has given some advantages on time computing and high efficiency. Theoritically, the deconvolution can be considered as inversion technique to invert the single seismic trace to the reflectivity, but it has not been successfully adopted due to noisy signals of the real data set and unknown source wavelet. After stacking, the seismic traces are moved to zero offset, thus each seismic traces now can be a single trace that is created by convolving the seismic source wavelet and reflectivity. In this paper, the fundamental of $\iota_1$ norm deconvolution method will be introduced. The method will be tested by synthetic data and applied to improve the stacked section of gas hydrate.

  • PDF

CAUCHY-RASSIAS STABILITY OF A GENERALIZED ADDITIVE MAPPING IN BANACH MODULES AND ISOMORPHISMS IN C*-ALGEBRAS

  • Shin, Dong Yun;Park, Choonkil
    • Journal of the Chungcheong Mathematical Society
    • /
    • v.24 no.4
    • /
    • pp.617-630
    • /
    • 2011
  • Let X, Y be vector spaces, and let r be 2 or 4. It is shown that if an odd mapping $f:X{\rightarrow}Y$ satisfies the functional equation $${\hspace{50}}rf(\frac{\sum_{j=1}^{d}\;x_j} {r})+\;{\sum\limits_{\iota(j)=0,1 \atop {\sum_{j=1}^{d}}\;{\iota}(j)=l}}\;rf(\frac{\sum_{j=1}^{d}{(-1)^{\iota(j)}x_j}}{r}) \\({\ddag}){\hspace{160}}=(_{d-1}C_l-_{d-1}C_{l-1}+1)\;{\sum\limits_{j=1}^{d}\;f(x_j)}$$ then the odd mapping $f:X{\rightarrow}Y$ is additive, and we prove the Cauchy-Rassias stability of the functional equation in Banach modules over a unital $C^*$-algebra. As an application, we show that every almost linear bijection $h:{\mathcal{A}}{\rightarrow}{\mathcal{B}}$ of a unital $C^*$-algebra ${\mathcal{A}}$ onto a unital $C^*$-algebra ${\mathcal{B}}$ is a $C^*$-algebra isomorphism when $h(2^nuy)=h(2^nu)h(y)$ for all unitaries $u{\in}{\mathcal{A}}$, all $y{\in}{\mathcal{A}}$, and $n=0,1,2,{\cdots}$.

Performance Tests on a Solar Water Heating System in Thermosyphonic Flow (열사이폰식 태양열 온수시스템의 성능실험)

  • Kim, Doo-Chun;Park, Seung-Duk
    • The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
    • /
    • v.9 no.2
    • /
    • pp.93-103
    • /
    • 1980
  • A small domestic solar water heating system in thermosyphonic flow was tested in Seoul. The system consisted of four flat plate aluminium roll bond type collectors of total effective area $3.28m^2$ and a $280{\iota}$ storage tank. It was tilted $52^{\circ}$ relative to the horizon. And the collector plate, collector tube and storage tank were equiped with 14 thermocouples. As the results, the following facts were found; 1) To provide water at $55^{\circ}C$ for a family of four in Seoul, a collector area of $3-4m^2$ and a storage capacity of $180{\iota}- 200{\iota}$ are suggested. And this system can supply hot water at above $45^{\circ}C$ day about. 2) In the late afternoon hours, it might be advantageous to stop the flow in the system as heat losses to the environment increase unduly. 3) Without any hot water consumption throughout the day, water temperature distributions inside the storage tank was found almost linear. This indicates essentially no mixing inside the storage tank. 4) In case of a small domestic solar water heating system, it is better to employ a single transparent cover rather than double one.

  • PDF

THE EXTENSION OF THREE-WAY BALANCED MULTI-LEVEL ROTATION SAMPLING DESIGNS

  • Kim, K.W.;Park, Y.S.;Lee, D.H.
    • Journal of the Korean Statistical Society
    • /
    • v.35 no.4
    • /
    • pp.343-353
    • /
    • 2006
  • The two-way balanced one-level rotation design, $r_1^m-r_2^{m-1}$, and the three-way balanced multi-level rotation design, $r_1^m(\iota)-r_1^{m-1}$, were discussed (Park et al., 2001, 2003). Although these rotation designs enjoy balancing properties, they have a restriction of $r_2=c{\cdot}r_1$ (c should be a integer value) which interferes with applying these designs freely to various situations. To overcome this difficulty, we extend the $r_1^m(\iota)-r_1^{m-1}$ design to new one under the most general rotation system. The new multi-level rotation design also satisfies tree-way balancing which is done on interview time, rotation group and recall time. We present the rule and rotation algorithm which guarantee the three-way balancing. In particular, we specify the necessary condition for the extended three-way balanced multi-level rotation sampling design.

Analysis of asymmetric flow in annulus with square ribs by linearly- varying shear stress model (線型 亂流剪斷應力모델에 의한 直四角形 조도를 갖는 二重圓管內의 非對稱流動의 解析)

  • 이병곤;최영돈
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.11 no.1
    • /
    • pp.88-96
    • /
    • 1987
  • A method is presented to calculate the fiction factor and velocity distribution of asymmetric flow in rough channels and annuli. This method is derived from an assumption of linearly-varying shear stress which is different from Maubach's constant shear stress assumption. This method gives continuous velocity gradient at the position of maximum velocity and the predicted velocity profiles are in better agreements with experimental data than those obtained by Maubach's method. In this paper, a new correlation of roughness function is proposed and the predictions of friction factors by this correlation agree well with experimental data.

Feature Based Tool Path Planning and Modification for STEP-NC (STEP-NC의 피쳐 기반 공구경로 생성 및 갱신)

  • 조정훈;서석환
    • Korean Journal of Computational Design and Engineering
    • /
    • v.4 no.4
    • /
    • pp.295-311
    • /
    • 1999
  • An increasing attention is paid to STEP-NC, the next generation CNC controller interfacing STEP-compatible data. In this paper, we first propose an Architecture for the STEP-NC (called FBCC: Feature Baled CNC Controller) accepting feature code compatible with STEP-data, and executing NC motion feature by feature while monitoring the execution status. The main thrust of the paper has been to develop an automatic on-line tool path generation and modification scheme for milling operation. The tool path it generated iota each feature by decomposing into a finite number of primitive features. The key function in the new scheme is haw to accommodate unexpected execution results. In our scheme, the too1 path plinker is designed to have a tracing capability iota the tool path execution so that a new path can be generated from the point where the operation is stopped. An illustrative example is included to show the capability of the developed algorithm.

  • PDF

ON THE INFINITE PRODUCTS DERIVED FROM THETA SERIES II

  • Kim, Dae-Yeoul;Koo, Ja-Kyung
    • Journal of the Korean Mathematical Society
    • /
    • v.45 no.5
    • /
    • pp.1379-1391
    • /
    • 2008
  • Let k be an imaginary quadratic field, ${\eta}$ the complex upper half plane, and let ${\tau}{\in}{\eta}{\cap}k,\;q=e^{{\pi}{i}{\tau}}$. For n, t ${\in}{\mathbb{Z}}^+$ with $1{\leq}t{\leq}n-1$, set n=${\delta}{\cdot}2^{\iota}$(${\delta}$=2, 3, 5, 7, 9, 13, 15) with ${\iota}{\geq}0$ integer. Then we show that $q{\frac}{n}{12}-{\frac}{t}{2}+{\frac}{t^2}{2n}{\prod}_{m=1}^{\infty}(1-q^{nm-t})(1-q^{{nm}-(n-t)})$ are algebraic numbers.