Browsing by Author "LEE, JC"

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DISCRETE GAUGE STATES AND W(INFINITY) CHARGES IN C=1 2D GRAVITY
(1995-05-04)
CHUNG, TD
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LEE, JC
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電子物理學系
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物理研究所
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Department of Electrophysics
We give a general formula for gauge states at the discrete momenta in Liouville theory. These discrete gauge states carry the w(infinity) charges. As in the case of the 26D (or 10D) string theory, they are decoupled from the correlation functions and can be considered as the symmetry parameters in the old covariant quantization of the theory.
EFFECT OF MILLING ON THE CAST MICROSTRUCTURE AND SINTERING BEHAVIOR OF MGO PARTIALLY-STABILIZED ZRO2
(1987-05-01)
TSENG, TY
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LEE, JC
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交大名義發表
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National Chiao Tung University
GENERALIZED ON-SHELL WARD IDENTITIES IN STRING THEORY
(1994-02-01)
LEE, JC
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交大名義發表
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物理研究所
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National Chiao Tung University
;
Institute of Physics
It is demonstrated that an infinite set of string-tree level on-shell Ward identities, which are valid to all sigma-model loop orders, can be systematically constructed without referring to the string field theory. As examples, bosonic massive scattering amplitudes are calculated explicitly up to the second massive excited states. Ward identities satisfied by these amplitudes are derived by using zero-norm states in the spectrum. In particular, the inter-particle Ward identity generated by the D2XD2, zero-norm state at the second massive level is demonstrated. The four physical propagating states of this mass level are then shown to form a large gauge multiplet. This result justifies our previous consideration on higher inter-spin symmetry from the generalized worldsheet sigma-model point of view.
HETEROTIC MASSIVE EINSTEIN-YANG-MILLS-TYPE SYMMETRY AND WARD IDENTITY
(1994-10-06)
LEE, JC
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物理研究所
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Institute of Physics
We show that there exist spontaneously broken symmetries for massive modes with transformation parameters theta((ab)) ([mu>upsilon]) theta((ab)) (mu) etc, containing both Einstein and E(8) circle times E(8) (or 50(32)) Yang-Mills indices in the 10D Heterotic string. The corresponding on-shell Ward identities are also constructed.
MASSIVE INTER-PARTICLE SYMMETRY AND WARD IDENTITY IN FERMIONIC STRING THEORY
(1995-01-01)
LEE, JC
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交大名義發表
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物理研究所
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National Chiao Tung University
;
Institute of Physics
We show that there exist enlarged stringy (alpha'-->infinity) symmetries for (even G-parity) massive modes in the 10D fermionic string theory. These symmetries are derived from on-shell Ward identities corresponding to the decoupling of massive gauge states in the spectrum. In the generalized massive supersymmetric sigma-model formalism, some symmetry transformations relate particles with different spins in the first order weak field approximation.
NONPERTURBATIVE DEFORMATION OF CONFORMAL FIELD-THEORY AND SPONTANEOUSLY BROKEN INTER MASS LEVEL SYMMETRIES IN STRING THEORY
(1993-09-01)
LEE, JC
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交大名義發表
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電子物理學系
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National Chiao Tung University
;
Department of Electrophysics
We study the deformation of conformal field theory without leaving the fixed points. It is found that an infinite number of higher spin background fields are needed to cancel the q-number anomalies when one goes beyond first order weak field calculation. This phenomenon can be interpreted in string theory as spontaneously broken symmetries between particles with different masses.
ON ESTIMATION AND PREDICTION PROCEDURES FOR AR(1) MODELS WITH POWER TRANSFORMATION
(1993-08-01)
LEE, JC
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TSAO, SL
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統計學研究所
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Institute of Statistics
The power transformation of Box and Cox (1964) has been shown to be quite useful in short-term forecasting for the linear regression model with AR(1) dependence structure (see, for example, Lee and Lu, 1987, 1989). It is crucial to have good estimates of the power transformation and serial. correlation parameters, because they form the basis for estimating other parameters and predicting future observations. The prediction of future observations is the main focus of this paper. We propose to estimate these two parameters by minimizing the mean squared prediction errors. These estimates and the corresponding predictions compare favourably, via revs and simulated data, with those obtained by the maximum likelihood method. Similar results are also demonstrated in the repeated measurements setting.
REDUCTION OF STRINGY SCATTERING-AMPLITUDES THROUGH MASSIVE WARD IDENTITIES
(1994-07-01)
LEE, JC
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交大名義發表
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電子物理學系
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National Chiao Tung University
;
Department of Electrophysics
It is shown that the scattering amplitudes of some degenerate massive string states can be expressed in terms of that of higher spin states at the same mass level. This phenomenon is discussed from sigma-model point of view and demonstrated explicitly by using massive Ward identities generated by zero-norm states at D = 26. The subtlety of the scalar propagating state is briefly pointed out. We also compare our on-shell gauge symmetry derived from sigma-model with off-shell gauge symmetry of covariant string field theo
SPONTANEOUSLY BROKEN SYMMETRY IN STRING THEORY
(1994-04-28)
LEE, JC
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物理研究所
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Institute of Physics
By using zero-norm states in the spectrum, we explicitly demonstrate the existence of an infinite number of high energy symmetry structures of the closed bosonic string theory. Each symmetry transformation (except those generated by massless zero-norm states) relates infinite particles with different masses, thus they are broken spontaneously at the Planck scale as previously conjectured by Gross and Evans and Ovrut. As an application, the results of Das and Sathiapalan which claim the sigma-model is nonperturbatively nonrenormalizable were reproduced from a stringy symmetry argument point of view.
SUPERCONFORMAL DEFORMATION, ZERO-NORM STATES AND SPACE-TIME SYMMETRIES OF THE SUPERSTRING THEORIES
(1992-05-01)
LEE, JC
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交大名義發表
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電子物理學系
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National Chiao Tung University
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Department of Electrophysics
We present a formalism to study type II and Heterotic superstrings with massless and massive background fields in the bosonic sector. This formalism is appropriate to study high energy symmetries of the superstring. As an example, we explicitly relate all massless symmetries to the massless zero-norm states in the spectrum. This includes the E8 x E8 and SO(32) gauge symmetries in the ten-dimensional Heterotic string. The first (even G-parity) massive level is briefly described. We then argue the existence of new symmetries for the massive Yang-Mills-like gauge bosons and tensor fields at each fixed mass level. These enlarged stringy symmetries correspond to the decoupling of massive zero-norm states in the spectrum.
SYSTOLIC IMPLEMENTATION OF KALMAN FILTER
(1994)
CHEN, SG
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LEE, JC
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LI, CC
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電子工程學系及電子研究所
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Department of Electronics Engineering and Institute of Electronics
VLSI NEUROPROCESSORS FOR VIDEO MOTION DETECTION
(1993-03-01)
LEE, JC
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SHEU, BJ
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FANG, WC
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CHELLAPPA, R
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交大名義發表
The system design of a locally connected competitive neural network for video motion detection is presented. The motion information from a sequence of image data can be determined through a two-dimensional multiprocessor array in which each processing element consists of an analog neuroprocessor. Massively parallel neurocomputing is done by compact and efficient neuroprocessors. Local data transfer between the neuroprocessors is performed by using an analog point-to-point interconnection scheme. To maintain strong signal strength over the whole system, global data communication between the host computer and neuroprocessors is carried out in a digital common bus. A mixed-signal very large scale integration (VLSI) neural chip that includes multiple neuroprocessors for fast video motion detection has been developed. Measured results of the programmable synapse, and winner-take-all circuitry are presented. Based on the measurement data, system-level analysis on a sequence of real-world images was conducted. A 1.5 x 2.8-cm2 chip in a 1.2-mum CMOS technology can accommodate 64 velocity-selective neuroprocessors. Each chip can achieve 83.2 giga connections per second. The intrinsic speed-up factor over a Sun-4/75 workstation is around 180.