• Journal of applied mathematics & informatics
• /
• v.28 no.3_4
• /
• pp.739-751
• /
• 2010

This article presents the result on existence, uniqueness and stability of mild solution of impulsive stochastic partial neutral functional differential equations under sufficient condition. The results are obtained by using the method of successive approximation.

• 전기의세계
• /
• v.30 no.9
• /
• pp.579-581
• /
• 1981

A rendezvous method via delayed state feedback is presented for a class of linear systems with time-delays. The property of pointwise degeneracy of delay differential system is utilized and it is shown that the controller is a minimun-time suboptimal controller.

• ETRI Journal
• /
• v.25 no.5
• /
• pp.369-378
• /
• 2003

Using the general switch management protocol on a multi-protocol label switching network, we present an efficient method for handling handovers. The proposed method directly changes an established path into a new path for supporting a handover. Our investigation reveals the effects of the proposed scheme and demonstrates that this method significantly reduces signaling costs and delays.

• International Journal of Highway Engineering
• /
• v.15 no.6
• /
• pp.125-133
• /
• 2013

PURPOSES : The purpose of this study is to propose delay-minimizing operation methodology of a signalized intersection based upon optimization of lane-uses on approaching lanes for an intersection. METHODS : For the optimization model of lane-uses, a set of constraints are set up to ensure feasibility and safety of the lane-uses, traffic flow, and signal settings. Minimization of demand to saturation flow ratio of a dual-ring signal control system is introduced to the objective function for delay minimization and effective signal operation. Using the optimized lane-uses, signal timings are optimized by delay-based model of TRANSYT-7F. RESULTS : It was found that the proposed objective function is great relation with delay time for an intersection. From the experimental results, the method was approved to be effective in reducing delay time. Especially, cases for two left-turn lanes reduced greater delays than those for a left turn lane. It is noticed that the cases for different traffic volume by approach reduced greater delays than those for the same traffic volume by approach. CONCLUSIONS : It was concluded that the objective function is proper for lane-uses optimizing model and the operation method is effective in reducing delay time for signalized intersections.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.23 no.4
• /
• pp.39-46
• /
• 2009

In this paper, we propose a full digital capacitive sensing touch key reducing the effects due to the variations of resistance and clock frequency. The proposed circuit consists of two capacitive loads to measure and a resistor between the capacitive loads. The method measures the delays of the resistor and two capacitive loads, respectively. The ratio of the two delays is represented as the ratio of the two capacitive loads and is irrelative to the resistance and the clock frequency if quantization error is disregarded. Experimental results show the proposed scheme efficiently reduces the effects due to the variations of clock frequency and resistance. Further more the method has l.04[pF] resolution and can be used as a touch key.

• Korean Journal of Childcare and Education
• /
• v.10 no.2
• /
• pp.213-236
• /
• 2014

This study is aimed at enhancing the prosocial behaviors and the positive peer play interaction of young children with developmental delays. Three children with developmental delays and three students without developmental delays who were 4-year-old students in an inclusive classroom were selected. Their homeroom teacher carried out the program with a small group of 6 children totaling 21 sessions over 3 months. The major results of this study were as follows: First, the result of both the observer and the parents' test after the program showed that the small group made positive changes on prosocial behaviors. In addition the frequency of target behaviors increased during the intervention. Second, the result of both the observer and the parents' test after the program showed that positive peer play interaction increased in the small group. Moreover the negative peer play interaction such as play disturbance and play isolation decreased. In conclusion, the thematic fantasy play program is useful for an inclusive classroom, and can be a concrete method to support inclusive education and childcare.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.23 no.8
• /
• pp.80-85
• /
• 2009

In this paper, we propose a full digital capacitive sensing touch key reducing the effects due to the variations of resistance and clock frequency. The proposed circuit consists of two capacitive loads to measure and a resistor between the capacitive loads. The method measures the delays of the resistor and two capacitive loads, respectively. The ratio of the two delays is represented as the ratio of the two capacitive loads and is irrelative to the resistance and the clock frequency if quantization error is disregarded. Experimental results show the proposed scheme efficiently reduces the effects due to the variations of clock frequency and resistance. Further more the method has 1.04[pF] resolution and can be used as a touch key.

• Journal of the Institute of Electronics Engineers of Korea SD
• /
• v.46 no.6
• /
• pp.25-30
• /
• 2009

In this paper, a full-digital capacitive sensor for touch key applications is proposed. The proposed circuit consists of two capacitive loads to measure and a resistor between the capacitive loads. As the method measures the delays of the resistor and two capacitive loads respectively, and obtains difference between the capacitive loads by subtracting the two delays, it can reduce the effects of changing of operating environment variables such as supplying voltage, temperature and humidity. Experimental results show the method has l.02pF resolution and can be applied to touch key applications.

• Journal of Ship and Ocean Technology
• /
• v.8 no.3
• /
• pp.18-25
• /
• 2004

Sound reception system is required to detect the sound and the quadrantal direction of the other ship's horn sound, to overcome the effects of enclosed wall for navigation space, functioning as a sound barrier. However, the realized systems can only provide quadrantal information of the other ship. This paper presents a new arrangement of microphones, having geometrically symmetric deployment with the same distances between sensors and the same angles between adjacent sensors with respect to the geometrical center. The sound pressures received at microphones are transformed into the related envelope signals by applying Hilbert transform. The time delays between microphones are estimated by the correlation functions between the derived envelope signals. This envelope base processing mitigates the noises related to the reflection by ship and sea surface. Then, the directional information is easily defined by using the estimated time delays. The suggested method is verified by the generated signals using boundary element method for a small ship model with sea surface wave. The estimated direction is quite similar to the true one and therefore the proposed approach can be used as an efficient sound reception system.

• Smart Structures and Systems
• /
• v.25 no.5
• /
• pp.569-580
• /
• 2020

The identification of delays and delay compensation are critical problems in real-time hybrid simulations (RTHS). Conventional delay compensation methods are mostly based on the assumption of a constant delay. However, the system delay may vary during tests owing to the nonlinearity of the loading system and/or the behavioral variations of the specimen. To address this issue, this study presents an adaptive delay compensation method based on a discrete model of the loading system. In particular, the parameters of this discrete model are identified and updated online with the least-squares method to represent a servo hydraulic loading system. Furthermore, based on this model, the system delays are compensated for by generating system commands using the desired displacements, achieved displacements, and previous displacement commands. This method is more general than the existing compensation methods because it can predict commands based on multiple displacement categories. Moreover, this method is straightforward and suitable for implementation on digital signal processing boards because it relies solely on the displacements rather than on velocity and/or acceleration data. The virtual and real RTHS results show that the studied method exhibits satisfactory estimation smoothness and compensation accuracy. Furthermore, considering the measurement noise, the low-order parameter models of this method are more favorable than that the high-order parameter models.