• Journal of the Institute of Electronics and Information Engineers
• /
• v.54 no.4
• /
• pp.75-80
• /
• 2017

ES (Electronic Warfare Support System) collects radar signals, and analyzes the signals about frequency, pulse width, PRI (Pulse Repetition Interval), and etc. and then ES compares analyzed result with known radar signals to identify them. But there are two disadvantage. One is that use of known radar signals is in comparing step only. The other is that calculating PRI needs many operations. In this paper proposes a parallel reference correlation algorithm that uses GPGPU (General Purpose Graphics Processing Units) and can identify what signals are in received radar signals without calculating PRI.

• The Korean Journal of Ecology
• /
• v.21 no.3
• /
• pp.269-276
• /
• 1998

The study of the Rana plancyi, was done during the calling period at a pond in Osong, Chungbuk, Korea from May to the middle of August of 1996 and 1997. Five basic types of call-A, B, C, D, E, - were identified in Rana plancyi according to the structure of call types. The structure of A type call has only one pulse, B type call has two pulses and C, D type call has one separated pulse which is called introductory call and pulse group as follow it. On the other hand, E type call has 3-6 separate pulses. The interval between introductory call and pulse group is $0.73{\pm}0.29$ s(n=159) in C type call and $0.60{\pm}0.21$ s (n=48) in D type call. The number of pulses in the pulse group is $30.08{\pm}8.69$ in C type call and $15.78{\pm}2.40$ in D type call. An increase in water temperature induces a decrease in C and D type call duration (C type call r= -0.4153, p<0.001, D type call r=-0.7064, p<0.001). In case of C and D type call, the interval between introductory call and pulse group influenced more call duration than pulse group duration. We regarded A, B type call as a territorial call and C, D type call as a mating call and we recognized that E type call has the function of threat or alarm.

• 제어로봇시스템학회:학술대회논문집
• /
• 2000.10a
• /
• pp.176-176
• /
• 2000

Generally, discrete-time processing is applied to the uniformly-sampled signals. But, radars emit pulse trains with irregular time instances. In this paper, we formulate the radar pulse train as a stochastic discrete-time dynamic linear model. The estimation task can be done via linear signal processing using Kalman Filter and some considerations. As a result, we can estimate the pulse repetition interval of a pulse train and predict the time instances of the next pulses to be received.

• Proceedings of the KIEE Conference
• /
• 2002.07b
• /
• pp.1169-1171
• /
• 2002

In this paper, RFRPP(Random Frequency Randomized Pulse Position ) PWM for three-phase voltage-controlled inverters is proposed. The LLPWM(Lead-Lag PWM) techinquc is that three switching pulses are located randomly back and forth in each switching interval. But with the restriction of random distribution, the harmonic spectrum cannot be dispersedly and continuously distributed. This paper calculates the duty ratio of the switching pulse firstly. Second, the switching pulses are located randomly in the switching interval. Third, the fixed switching frequency of the space vector modulation is randomly varied. To verify the validity of the proposed technique, simulation study is tried using Matlab/Simulink. When a proposed techniquc is employed, the harmonic spectrum of the inverter output voltagc varies from one cycle to the next and the EMI(Electromagnetic Interference) and resonant vibration are greatly alleviated.

• Journal of the Ergonomics Society of Korea
• /
• v.2 no.2
• /
• pp.3-10
• /
• 1983

While three subjects were running on treadmill at five different speeds, their heart beat interval times were measured and analyzed. From the analysis, we discovered some relation- ships between workload and cardiac response, especially cardiac arrhythmia. Using these relationships, a physioligical model for estimating workload was developed. Although pulse rate has been considered as a good measure of physical load, this study shows that it is highly subject dependent and therefore unsuitable for task evalution. It is recommended to use range of heart beat interval times rather than pulse rate in the evaluation of light work.

• Journal of Biomedical Engineering Research
• /
• v.31 no.1
• /
• pp.14-19
• /
• 2010

Baroreflex sensitivity (BRS) is a parameter of the cardiovascular system that is reflected in changes in pulse interval (PD and systolic blood pressure (SBP). BRS contains information about how the autonomic nervous system regulates hemodynamic homeostasis. Normally the beat-to-beat SBP measurement and the pulse interval measured from the electrocardiogram (ECG) are required to estimate the BRS. We investigated the possibility of measuring BRS in the absence of a beat-to-beat SBP measurement device. Pulse arrival time (PAT), defined as the time between the R-peak of the ECG and a single characteristic point on the pulse wave recorded from any arterial location was measured by photoplethysmography. By comparing the BRS obtained from conventional measurements with our method during controlled breathing, we confirmed again that PAT and SBP are closely correlated, with a correlation coefficient of -0.82 to -0.95. The coherence between SBP and PI at a respiration frequency of 0.07-0.12 Hz was similar to the coherence between PAT and PI. Although the ranges and units of measurement are different (ms/mmHg vs. ms/ms) for BRS measured conventionally and by our method, the correlation is very strong. Following further investigation under various conditions, BRS can be reliably estimated without the inconvenient and expensive beat-to-beat SBP measurement.

• Journal of the Korean Institute of Telematics and Electronics
• /
• v.7 no.4
• /
• pp.6-13
• /
• 1970

The variable-width and double-pulse generator Here described is completely transistorized so its size is small and it is convenient to handle. The frequency ran be varied from 1 KHz to 500KHz, the pulse width from 0.4$\mu$sec to 8$\mu$sec, amplitude from 1V to 10V, and interval of double pulse from 0$\mu$sec to 12$\mu$sec. Positive and negative signal or double pulse trains can he obtained. An analysis has been carried out for each stage and the design equations are derived. The experimental results are compared with the analysis.

• ETRI Journal
• /
• v.37 no.2
• /
• pp.241-250
• /
• 2015

In this paper, we present novel high-speed transmission schemes for high-speed ultra-high frequency (UHF) radio-frequency identification communication. For high-speed communication, tags communicate with a reader using a high-speed Miller (HS-Miller) encoding and multiple antennas, and a reader communicates with tags using extended pulse-interval encoding (E-PIE). E-PIE can provide up to a two-fold faster data rate than conventional pulse-interval encoding. Using HS-Miller encoding and orthogonal multiplexing techniques, tags can achieve a two- to three-fold faster data rate than Miller encoding without degrading the demodulation performance at a reader. To verify the proposed transmission scheme, the MATLAB/Simulink model for high-speed backscatter based on an HS-Miller modulated subcarrier has been designed and simulated. The simulation results show that the proposed transmission scheme can achieve more than a 3 dB higher BER performance in comparison to a Miller modulated subcarrier.

• Journal of Chest Surgery
• /
• v.22 no.4
• /
• pp.548-561
• /
• 1989

In single atrial cells isolated from the rabbit the properties of inward current of Na-Ca exchange were investigated using the whole cell voltage clamp technique. The current was recorded during repolarization following brief 2 ms depolarizing pulse to +40 mV from a holding potential of * 70 mV. Followings are the results obtained: 1. When stimulated every 30 seconds, the inward currents were activated and reached peak values 6-12 ms after the beginning of depolarizing pulse. The mean current amplitude was 342 pA/cell. 2. The current decayed spontaneously from the peak activation and the time course of the relaxation showed two different phases fast and slow phase. The time constants were 10-18 ms and 60-140 ms, respectively. 3. The recovery of inward current was tested by paired pulse of various intervals. The peak current recovered exponentially with time constant of 140 ms and 1 p M isoprenaline accelerated the recovery process. 4. Relaxation time course was also affected by pulse interval and time constant of the fast phase was reduced almost linearly according to the decrease of pulse interval between 30 sec and 1 sec. 5. The peak activation was increased in magnitude by long prepulse stimulation, 5 p M Bay K, 1 p M isoprenaline or internal and external application of c-AMP. 6. The relaxation time constant of the fast phase was prolonged by 5 p M Bay K or c-AMP, and shortened by isoprenaline. However the time course of the slow relaxation phase was not so much changed. From the above results, it could be concluded that increase of the calcium current by Bay K or c-AMP results in the potentiation and prolongation of intracellular calcium transient, and the facilitation of Ca uptake by SR might be a mechanism of shortening the time constant of current relaxation by short interval stimulation or isoprenaline.

• Journal of IKEEE
• /
• v.15 no.2
• /
• pp.171-178
• /
• 2011

In this paper, a novel pulse repetition interval (PRI) jittering coder based on quasi-random M-sequence codes is proposed for improvement of counter-countermeasure capability in a radar. Each of the proposed jittered 256 PRI codes has a unique code chip combination with 256 code chips, such that any set of three consequent code chips (4 pulses) from any code appears only once among the entire code chip sequences of the codes. This indicates that only 4 of received pulses are enough to determine uniquely the exact timing position of the incoming pulse train (or code chip sequence) required for counter-countermeasure, as well as the identity of the transmitted code. To prove the proposed idea experimentally, the jittered PRI coder is implemented and demonstrated.