• Journal of Broadcast Engineering
• /
• v.1 no.2
• /
• pp.85-95
• /
• 1996

The purpose of this paper Is to propose a dubbed signal time-synchroniztion technique based on the SOLA(Synchronized Over-Lap and Add) method which has been widely used to modify the time scale of speech signal. In broadcasting audio recording environments, the high degree of background noise requires dubbing process. Since the time difference between the original and the dubbed signal ranges about 200mili seconds, process is required to make the dubbed signal synchronize to the corresponding image. The proposed method finds he starting point of the dubbing signal using the short-time energy of the two signals. Thereafter, LPC cepstrum analysis and DTW(Dynamic Time Warping) process are applied to synchronize phoneme positions of the two signals. After determining the matched point by the minimum mean square error between orignal and dubbed LPC cepstrums, the SOLA method is applied to the dubbed signal, to maintain the consistency of the corresponding phase. Effectiveness of proposed method is verified by comparing the waveforms and the spectrograms of the original and the time synchronized dubbing signal.

• The Journal of the Korea institute of electronic communication sciences
• /
• v.10 no.8
• /
• pp.883-890
• /
• 2015

As the semiconductor processing technology has been developing, multiple cores or NoC(network on chip) can be contained in recent chips. GALS(globally asychronous locally synchronous) clocking scheme that has multi-clock domains with different frequencies or phase differences is widely used to solve power consumption and clock skew in a large chip with a single clock. A synchronizer is needed to avoid a synchronization problem between sender and receiver in GALS. In this paper, the setup and hold time of DFF required to design the synchronizer are measured using 180nm CMOS processing parameters depending on temperature, supply voltage, and the size of inverter in DFF. The simulation results based on the bisection method in HSPICE show that the setup and hold time are proportional to temperature, however they are inversely proportional to supply voltage, and negative values are measured for the hold time.

• Korean Institute of Interior Design Journal
• /
• v.22 no.3
• /
• pp.91-99
• /
• 2013

It is easier to objectify the designing process with the analysis of how users perceive any space depending on the purpose of space visiting in the interactions of them and images. This study analyzed the observation characteristics perceived through observation frequency and time depending on the purpose cafe customers to understand what effect the design factors constructing the space has on the observation characteristics which are the results obtained as information through visual perception. The followings are the results of this study. First, The time range for searching or wandering and the observation characteristics could be estimated by the meaning of observation time by grade with the setup of time-range out of the distribution of sections. Second, at the time distribution by section, when there was intention, the observation time was found to have higher occupation. Third, though the higher section frequency is likely to have more observation time, the grades of II/V had higher frequency of [Intention] and the time had higher [Non-Intention], which revealed that there is a tendency for the observation characteristics vary in a large degree depending on whether there was intention or not. Fourth, by the application of the observation characteristics of each grade for interrelation analysis depending on whether there is any intention to the space of cafe, the detailed space characteristics could be compared with observation tendency. The difference of obtained information has an effect on obtaining perceived information, and since the intention may affect any information which is obtained, it is necessary for design information suitable to visit purpose or users' observation intention to be transferred in the process of designing. Analyzing the effect of any change to designing factors on the sight inducing intention and synchronization will help to understand the emotional design focused on users.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.24 no.1
• /
• pp.52-57
• /
• 2014

This paper presents an implementation of a smooth path planning method considering physical limits on a real time operating system for a two-wheel mobile robot. A Bezier curve is utilized to make a smooth path considering a robot's position and direction angle through the defined path. A convolution operator is used to generate the center velocity trajectory to travel the distance of the planned path while satisfying the physical limits. The joint space velocity is computed to drive the two-wheel mobile robot from the center velocity. Trajectory planning, velocity command according to the planned trajectory, and monitoring of encoder data are implemented with a multi-tasking system. And the synchronization of tasks is performed with a real-time mechanism of Event Flag. A real time system with multi-tasks is implemented and the result is compared with a non-real-time system in terms of path tracking to the designed path. The result shows the usefulness of a real-time multi-tasking system to the control system which requires real-time features.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.18 no.6
• /
• pp.1317-1322
• /
• 2014

This paper shows effects of tropospheric delay models and mapping functions among delay features occurred when GPS code signal is transferred for GPS Time Transfer. GPS time transfer uses CGGTTS as the international standard format. For geodetic GPS receiver, ROB has provided r2cggtts software which generates CGGTTS data from RINEX data and all laboratories participated in TAI link use this software and send the CGGTTS results periodically. Though Saastamoinen zenith path model and Niell mapping function are commonly used in space geodesy, r2cggtts software applied NATO zenith path model and CHAO mapping function to the tropospheric delay model. Hence, this paper shows effects of two tropospheric delay models by implementing Saastamoinen model and Niell mapping function for the time offset.

• Journal of Digital Convergence
• /
• v.10 no.10
• /
• pp.289-294
• /
• 2012

In this paper, we take advantage of the characteristics of mobile smartphones can be serviced without the constraints of time and space, and Study was developed by a variety of mobile services were done in a traditional offline can be implemented in real-time Case Management Community. To this end, in addition to general PC/laptop, smart mobile until the configuration interface provide the same environment for HTML5 Web Switching and Optimal Network on the same device-specific browser Size to the implementation of the next generation of Web standards, HTML5-based integrated case management Web and Mobile Web. Hybrid App Development OS supports various kinds of smart devices based on SenchaTouch Mobile Framework between the server real-time synchronization and message through the implementation of the Push Notification function, administrators and guardians real-time two-way communication between the subjects is a real-time implementation of the system was implemented Case Management Community.

• The KIPS Transactions:PartD
• /
• v.10D no.2
• /
• pp.187-194
• /
• 2003

Main Memory storage system can increase the performance of the system by assigning enough slack time to real-time transactions. Due to its high response time of main memory devices, main memory resident data management systems have been used for location management of personal mobile clients to cope with urgent location related operations. In this paper we have developed a multi-threaded main memory storage system as a core component of real-time retrieval system to handle a huge amount of readers and writers of main memory resident data. The storage system is implemented as an embedded component which is working with the help of a disk resident database system. It uses multi-threaded executions and utilizes latches for its concurrency control rather than complex locking method. It only saves most recent data on main memory and data synchronization is done only when disk resident database asks for update transactions. The system controls the number of read threads and update threads to guarantee the minimum requirements of real-time retrievals.

• The Transactions of the Korea Information Processing Society
• /
• v.6 no.12
• /
• pp.3652-3661
• /
• 1999

To support multimedia applications such as a multimedia communication systems and multimedia broadcasting, an operating system need to predict their timing-constraints. So, In this real-time systems, we must solve the priority inversion problem that may make the behavior of unpredictable systems and need a real-time server model that provides a better preemptability and minimizes a system overhead. In current real-time systems, the single thread server model, the worker model and the dynamic server model are being used for synchronization but they cannot propose an effective structure for managing shared resources. In this paper, the priority inheritance protocol is used to solve the priority inversion problem and the hybrid prioritized worker model is proposed, which can provide a more effective structure and a faster response time minimizing a system overhead. The hybrid prioritized worker model is to combine the static and the dynamic prioritized worker model, and have a better performance than other models in response time which is an important factor in a real-time system.

• Journal of the Institute of Convergence Signal Processing
• /
• v.22 no.2
• /
• pp.64-70
• /
• 2021

Nowadays, there are significant interests in real-time remote control using wireless networks. In implementing real-time remote control, one important factor is delay performance of real-time control message. Especially, the technique to reduce jitter of delay is necessary in transmitting periodically real-time control message. In this paper, we proposed synchronized transmission to reduce jitter of delay, when real-time control message was transmitted through wireless networks. The proposed transmission kept synchronization between source node and wireless transmitter and controlled transmission instance to transmit real-tie control message with fixed delay in wireless networks. According to results of experiment in military unmanned vehicle system, the proposed transmission reduced jitter of delay as 32% as that of a non-employing case.

• Proceedings of the Korean Society of Surveying, Geodesy, Photogrammetry, and Cartography Conference
• /
• 2007.04a
• /
• pp.417-420
• /
• 2007

Mobile facility management system is a on-site management tool to collect and update various facility data. But there is a chance to make a data inconsistency between lot of concurrent workers. And facility management system requires to keep records about work log within a certain period of time. This paper describes the design and implementation of mobile facility management system, which provide efficient data synchronization mechanism using version managent technique on large facility data in concurrent work environment. And proposed system is able to keep workers update log persistently.