• KSII Transactions on Internet and Information Systems (TIIS)
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• v.15 no.10
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• pp.3858-3874
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• 2021

As an essential part of the urban transportation system, precise perception of the traffic flow parameters at the traffic signal intersection ensures traffic safety and fully improves the intersection's capacity. Traditional detection methods of road traffic flow parameter can be divided into the micro and the macro. The microscopic detection methods include geomagnetic induction coil technology, aerial detection technology based on the unmanned aerial vehicles (UAV) and camera video detection technology based on the fixed scene. The macroscopic detection methods include floating car data analysis technology. All the above methods have their advantages and disadvantages. Recently, indoor location methods based on wireless signals have attracted wide attention due to their applicability and low cost. This paper extends the wireless signal indoor location method to the outdoor intersection scene for traffic flow parameter estimation. In this paper, the detection scene is constructed at the intersection based on the received signal strength indication (RSSI) ranging technology extracted from the wireless signal. We extracted the RSSI data from the wireless signals sent to the road side unit (RSU) by the vehicle nodes, calibrated the RSSI ranging model, and finally obtained the traffic flow parameters of the intersection entrance road. We measured the average speed of traffic flow through multiple simulation experiments, the trajectory of traffic flow, and the spatiotemporal map at a single intersection inlet. Finally, we obtained the queue length of the inlet lane at the intersection. The simulation results of the experiment show that the RSSI ranging positioning method based on wireless signals can accurately estimate the traffic flow parameters at the intersection, which also provides a foundation for accurately estimating the traffic flow state in the future era of the Internet of Vehicles.

• Journal of the Korean Society for Heat Treatment
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• v.37 no.3
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• pp.114-120
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• 2024

AA 2026, which is used as an aviation material, is an improved version of 2024 and has higher physical properties, and is a material that has the potential to be applied to supersonic aircraft to be developed in the future. However, when an aircraft exceeds supersonic speeds, the surface heats up and the material must be resistant to this. Therefore, this study confirmed the high-temperature properties of AA 2026, an aviation structural material. AA 2026, solution treated at 500℃ for 4hr, was naturally aged at room temperature for more than 168 hr. Changes in microstructure and physical properties were confirmed over several hours of exposure to 100℃, 200℃, and 300℃, respectively. As a result of microstructure analysis, there was no significant change at 100℃, and from 200℃, GPB, a strengthening mechanism, grew and formed an S Phase. It was confirmed that the S Phase grew as the exposure time increased. Through a tensile test, it was confirmed that physical properties deteriorated as the precipitates grew. However, it was confirmed that the properties were stably maintained at 100℃, which is the temperature when the speed of a supersonic aircraft is less than Mach 2.

• Journal of the Korea Convergence Society
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• v.7 no.6
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• pp.249-258
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• 2016

In this research, we analyzed the research and development process of small and medium enterprises, and diagnosed the problem of the research and development process of domestic small and medium enterprises, and evaluated the influence of innovative ability on the speed of research and development and corporate performance. In evaluating these effects, it is possible to grasp the direction of power generation according to the type of analysis, taking into account the meltdown factor of factors related to innovative capabilities. The main purpose of this research is to confirm the influence on the speed of research and development according to the innovative capacity and business environment and to verify the reliability and validity of the research by Klumbach alpha Was used. In this research, we analyzed how the speed of R & D affects R & D activities, it is a research aimed at the necessity of a resource-based approach to the internal capacity of a company, Have a valuable value. Based on the influence on the company, each factor is a research that analyzed the influence on R & D and financial indicators through maintaining company's development level, Research that has practical value that can base on the development of R & D capacity on corporate strategy formulation.

• 제어로봇시스템학회:학술대회논문집
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• 1996.10a
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• pp.13-16
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• 1996

Based on the technical innovation of the recent communication system technologies, systems are linked by the worldwide network. We introduce some examples of the multimedia network systems. Especially, we introduce our recent attempt to realize the multimedia tele-surgery system using high speed optical fiber network. At first, we shows the technical problems of the multimedia tele-surgery. We applied this idea to the intravascular neurosurgery. System configuration for the prototype experiments and experimental results are shown.

• The Journal of Information Technology
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• v.12 no.4
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• pp.11-17
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• 2009

In this paper, frequency synthesizer for radar system is designed and developed. Optimizing the phase noise and lock time, each module is designed as two-type PLL circuit, and then the performance of PLL frequency synthesizer is compared. The experiment result shows the lock time of 70 usec, the phase noise of less then 100 dBc, the bandwidth above 500MHz.

• The Journal of Information Technology
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• v.4 no.4
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• pp.51-63
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• 2001

Residue Number System has carry free operation and parallelism each modulus, So it is used for special purpose processor such as Digital Signal Processing and Neuron Processor. Magnitude comparison and sign detection are in need of Mixed Radix Conversion, and these operations are impediment to improve the operation speed. So in this Paper, MRC(Mixed Radix Converter) is designed using modified partitioned residue to speed up the operation of MRC, so it has progressed maximum twice operation time but increased the size of converter comparison to other converter.

• Journal of Korean Institute of Industrial Engineers
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• v.32 no.4
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• pp.298-313
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• 2006

Six sigma is focused on quality improvement through variation reduction, while lean is on process flow improvement and lead time reduction by waste elimination. However, lean cannot bring a process under statistical control and six sigma alone cannot dramatically improve process speed. Lean six sigma was developed to achieve faster rate of improvement in customer satisfaction, cost, quality, process speed, and invested capital. In this paper we present the importance of using value stream mapping and suggest a guideline on how to integrate lean and six sigma by is proposed.

• The Journal of Information Technology
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• v.5 no.4
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• pp.145-154
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• 2002

The Extension of Base is a fundamental Method to expend the moduli in RNS(Residue Number System). RNS has the benefit of parallelism and no carry propagation at each moduli, but division , extension of base and etc. is the problem of RNS in case of the operation speed.Generally this method is applied to system using Mixed Radix Conversion. it appears to decrease the size of Arithmetic Unit, but increasing the time of operation. So in this paper, the Improved Extension of Base is proposed using Chinese Remainder Theorem. it has the comparative small size and Improved speed.

• The Journal of Information Technology
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• v.5 no.2
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• pp.47-54
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• 2002

OFDM ambient noise and entrain error that this research proposes in IEEE 802.11g, use 256-State 2/3 binary scale Convoulutional 8-PSK Modulations, FEC coding, PBCC and did speed of 12 Mbpses that belong on category of 5 GHzs Band FHSS way so that can be applied in 20 Mbpses DSSS'S generalization that is establishing Pyojunan in current IEEE embodying transmission device model who operate with the equal speed from 2.4 GHzs ISM Band important duty to DSSS way.

• The Journal of Information Technology
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• v.9 no.4
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• pp.65-74
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• 2006

The back propagation of neural networks has the problems of falling into local minimum and delay of the speed by the iterative learning. An algorithm to solve the problem and improve the speed of the learning was already proposed in[8], which updates the learning parameter related with the connection weight. In this paper, we propose the algorithm generating initial weight to improve the efficiency of the algorithm by offering the difference between the input vector and the target signal to the generating function of initial weight. The algorithm proposed here can classify more than 98.75% of the handwritten digits and this rate shows 30% more effective than the other previous methods.