Ealgoo Kim

An efficient global motion characterization method for image processing applications

A very hardware and computational efficient method for frame motion characterization is presented. The method replaces the time consuming calculation of two-dimensional m/spl times/n picture elements with that of two one-dimensional vectors. This is made possible by mathematically operating the luminance values of vertical and horizontal lines as the characteristic values of x and y direction respectively; either by taking simply the weighted average values, or taking only those of the above-threshold values. By comparing these characteristic values taken from two frames in a sequence of moving pictures, one can extract the components of frame changes quantitatively into three factors; the factor caused by the motion of objects, or the factors caused by the panning, or zooming of the camera. The efficiency of this algorithm is examined with some practical examples, and application possibilities in an automatic motion tracking system and image stabilizer are discussed.

A global motion characterization method using one-dimensional characteristic curves for image processing applications

A very hardware and computation efficient method for frame motion characterization is developed. Instead of dealing a 2-dimensional m/spl times/n picture elements, this algorithm generates two 1-dimensional vectors, by mathematically operating the luminance values of vertical and horizontal lines as the characteristic valves of x and y direction, respectively. The efficiency of this algorithm is demonstrated by decomposition of frame changes into various factors: the motion of objects, panning and zooming. Applications in automatic motion tracking system and image stabilizer are discussed.

Signal splitting effect analysis for Muon tracker signal in frequency domain

This paper analyzes the effects of signal splitting in muon tracker front end electronics. Signal splitting is an effective strategy to upgrade muon tracker front end electronics and generate real-time signals for general trigger systems. However, signal splitting will affect the amplitude and bandwidth of split signals and if the splitting is not controlled properly, the output of muon tracker can be degraded to a degree which can not provide enough spatial accuracy or real-time trigger information. To properly control the effect of signal splitting, a qualitative analysis of signal splitting in muon tracker front end electronics is needed. In this paper, the transfer functions of both current and new front end electronics will be derived and the circuit parameters that affect the output signal characteristics will be analyzed in frequency domain. The circuit parameters include cathode strip capacitance, coupling capacitance, and feedback capacitance of the preamplifiers. Using the analysis result of this paper, the amplitude and frequency response of the split signal can be predicted and controlled effectively to achieve desired splitting ratio and frequency characteristics for muon tracker spatial accuracy and real-time trigger information.

An extraction algorithm of simplified IT characteristics curve from standard intelligent power switch (IPS) parameters

This paper proposed an algorithm to generate I-t curve of an IPS from its simplified model. The model used electrical and thermal characteristics of IPS like its on resistance (RON), thermal resistances (Rth) and capacitances (Cth) of its thermal circuit and its thermal tripping/shutdown temperature (TSHUTDOWN). I-t curves are extremely important for selection of an IPS for a particular load and wire in automotive industry. If only the IPS can sustain the load current and can protect the wire in case of a fault, it can be used for the application. This evaluation can be easily performed with the help of IPS I-t curve. The I-t curve generated using this algorithm was compared with that provided by the company (in application note) for some IPS. An application example using the I-t curve was also described. Finally the limitation of the model was mentioned and its effect was discussed with the help of the application example.

A method of a repetitive sampling measurement for OTDR considering a ghost effect to a short-range measurement with a short-length fiber

This paper discusses implementations of a repetitive sampling measurement for OTDR considering ghost effect for short period measurement with a short-length fiber. Repetitive sampling is done to acquire higher equivalent sampling rate with a low sampling clock in the data acquisition. However, the repetitive sampling can cause misalignment of ghost reflection which produces a distortion. This study analyzes the effect of ghost on the repetitive sampling measurement result. The implementations which can be categorized based on the delay object, delaying sequence, and delay loop steps are analyzed for the distortion possibility and proposed to avoid a misaligned ghost reflection measurement. The experiment with an OTDR that has an equivalent sampling rate of 10 GHz obtained using a 10 MHz sampling clock and 100 ps delay is shown to validate the method.

Signal splitting effect analysis on SNR and jitter requirement for Muon Tracker Detector

Signal splitting strategy is one of the methods to get implement circuit that gets real-time trigger timing information in addition to post trigger amplitude information in current muon tracker detector. Although signal splitting strategy is cost effective and need short development time, there can be degradation in SNR and jitter and it is needed to analyze the signal splitting effect on the original amplitude signal path and newly added timing signal path to ensure both signal paths requirements are met. This paper analyzes the relations between the signal splitting elements, the coupling capacitors, and the two signal paths requirements. The requirements are signal to noise ratio parameter for the amplitude signal path and jitter parameter for the timing signal path. The results and approach of this paper can be applied to other signal splitting applications to check the feasibility and to set correct splitting ratio which meets the multiple requirements of the application.