• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.12B
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• pp.1083-1096
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• 2008

This paper proposes an energy-aware path management scheme, so-called the TBP(Threshold based Back-Pressure) algorithm, which is designed for lifetime extension of the energy-constrained wireless sensor networks. With the goal of fair energy consumptions, we extensively utilize the available paths between the source and the sink nodes. The traffic distribution feature of the TBP algorithm operates in two scales; the local and the whole routing area. The threshold and the back-pressure signal are introduced for implementing those operations. It is noticeable that the TBP algorithm maintains the scalability by defining both the threshold and the back-pressure signal to have their meanings locally confined to one hop only. Throughout several experiments, we observe that the TBP algorithm enhances the network-wide energy distribution. which implies the extension of the network lifetime. Additionally, both the delay and the throughput outcomes show remarkable improvements. This shows that the energy-aware path control scheme holds the effects of the congestion control.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10b
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• pp.1116-1118
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• 1990

This paper describes the required frequency bandwidth which is used as a measure for the quality of the PFM transmission system to transmit the control signals. First, the PFM signal which has been distorted due to the frequency bandwidth limit on the transmission line is analyzed by Fourier transform and secondly distortion which has been observed at the receiver is numerically analyzed to make the frequency bandwidth required for transmitting the PFM signals. According to the analysis heretofore, the 50% threshold level for shaping the received PFM signal, which is of 50 % in TTL level, is superior than the 10- and 90-% threshold levels.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2013.05a
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• pp.886-888
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• 2013

An edge includes information of objects such as magnitude, orientation, and location. Conventional edge detection methods to detect those edge are methods using Sobel, Prewitt, Roberts, Laplacian operator. Existing methods use fixed weighted mask to detect edges, and their edge detection characteristics are insufficient. Therefore, to remedy weakness of conventional methods, in this paper, an edge detection algorithm using weight with standard deviation and thresholds is proposed.

• Proceedings of the KIEE Conference
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• 1999.07g
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• pp.3227-3229
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• 1999

수신된 초음파 파형이 표준 파형과 정합되는 시간을 수신 시점으로 사용함으로써 정확한 거리측정을 가능하게 하는 초음파 센서 거리계의 성능 개선을 제안하였다. 근거리 측정용으로 많이 사용되는 초음파센서는 다른 거리측정 시스템에 비해 하드웨어 구현이 용이하고 가격이 저렴한 장점이 있으나 센서 수신부측 Limit 회로의 threshold level의 선택 문제에 따른 거리 측정의 오차와 소음에 의한 거리 측정 오차가 매우 큰 문제가 되고 있다. 본 논문에서는 수신된 초음파 파형에 표준 파형을 정합하여 최대의 정합값을 가지는 시점을 수신 시간으로 간주하여, 소음환경비서도 거리 측정이 가능한 파형 정합 방법을 제한하였다. 본 논문의 실험을 통하여, 잡음이 심한 소음환경에서도 제안한 파형 정합 방법이 Threshold 방법 보다 초음파센서 거리 측정 성능이 개선됨을 확인할 수 있었다.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.11
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• pp.187-192
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• 2014

Various researches are performed to extract significant features from continuous images. The FAST algorithm has the simple structure for arithmetic operation and it is easy to extraction the features in real time. For this reason, the FPGA based hardware accelerator is implemented and widely applied for the FAST algorithm. The hardware accelerator needs the threshold to extract the features from images. The threshold is influenced not only the number of extracted features but also the total execution time. Therefore, the way of threshold control is important to stabilize the total execution time and to extract features as much as possible. In order to control the threshold, this paper proposes the PI controller. The function and performance for the proposed PI controller are verified by using test images and the PI control logic is designed based on Xilinx Vertex IV FPGA. The proposed scheme can be implemented by adding 47 Flip Flops, 146 LUTs, and 91 Slices to the FAST hardware accelerator. This proposed approach only occupies 2.1% of Flip Flop, 4.4% of LUTs, and 4.5% of Slices and can be regarded as a small portion of hardware cost.

• The Journal of the Korea Contents Association
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• v.19 no.10
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• pp.198-205
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• 2019

The purpose of this study was to identify whether cutaneous sensory (CS) changes induced by mechanical intervention(MI) increases the trigger point threshold and muscle tone of the same spinal segment to neck disc patients. Thirty persons with Neck disc patients were recruited in this experiment. The subjects consisted of 10 men and 20 women. The mechanical stimulus group induced CS changes for 5 minutes using the Graston instrument and the control group received no action. The CS changes were estimated by using the Von Frey Filament, PPT changes were measured by using the pressure threshold meter and msucle tone changes were measured by using Myotone pro. CS threshold increased significantly when MI was applied (p<0.05). On the same spinal segment, increases in the right infraspinatus PPT and muscle tone was observed (p<0.05) and decreases in the right trapezius PPT was observed(p<0.05). However, the PPT and muscle tone changes in other muscles were not significantly different. Furthermore, the control group CS, PPT and muscle tone were not significantly different. As a result, CS changes induced by MI make to change PPT and muscle tone on the same spinal segment. Therefore, application of MI to the same spinal segment may be of clinical significance as a new rehabilitation method for increasing pain threshold, muscle tone and pain control in neck disc patients.

• Journal of Broadcast Engineering
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• v.11 no.2 s.31
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• pp.191-199
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• 2006

This paper presents an efficient pre echo control scheme for MPEG Audio coders based on the psychoacoustic model II (PAM-II). Pre echo control is the final step for the calculation of masking threshold in the PAM II. It is to minimize the spread of quantization error over the processing frame. In the conventional encoders, pre echo is reduced by restricting the estimated masking threshold not to exceed the one obtained in the previous frame. The conventional method performs pre echo control not only for short blocks but also for long blocks, which lowers the masking threshold in long blocks and, in turn, increases the quantization noise level of corresponding blocks. This paper proposes an efficient pre echo control process. The test result shows a mean enhancement of more than 0.4 especially for complex signals on the ITU R 5 point audio impairment scale.

• The Journal of Korean Physical Therapy
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• v.6 no.1
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• pp.85-93
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• 1994

The purposes of this study were 1) to examine the effects of microcurrent electrical neuromuscular stimulation 2) to compare surface electrode with needle electrode at somatic acupuncture points on experimental pain threshold measured at the distal end of the radius 3) to determine the changes in effect over time. A total of sixty healthy adult male and female subjects were assigned randomly to one of two experimental group or to a control group. Group 1(n=20) received MENS(Microcurrent Electrical Neuromuscular Stimulation) with surface electrode. Group 2(n=20) received HENS with needle electrode. Group 3(n=20) received no MENS. It measured experimental pain threshold at the wrist on pretreatment, 0 min after treatment. 15 min after treatment, 30 min after treatment in two experimental group. The results were as follows: 1. Experimental pain thresholds were higher in males than females(P<0.01). 2. Only the experimental group exhibited a significant increased in pain threshold after MENS treatment(P<0.05). 3. Surface electrode group increased significant pain threshold 0 min, 15 min after treatment, but greatly decrease 30 min after treatment. 4. Needle electrode group increased significant pain threshold 0 min, 15 min after treatment, but decrease 30 min after treatment. The results suggest that MENS applied to appropriate somatic acupuncture point can increase pain threshold. Further research is needed to assess the effects of greatly variety intensity of MENS of pain sufferes.

• Journal of Oral Medicine and Pain
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• v.31 no.2
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• pp.113-120
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• 2006

The purpose of this study was to investigate whether there were any changes in taste sensitivity with oral lichen planus (OLP). Sixty subjects (26 males and 34 females) were included for the study and they were categorized into 2 groups (oral lichen planus 30 persons,control 30 persons), oral lichen planus group was investigated in the department of Oral Medicine, College of Dentistry, Pusan National University from April, 2005 to February, 2006 and control group was investigated in the clinic at Cheongju City from february, 2006 to april, 2006. The electrical taste thresholds were measured using an electrogustometer of the 4 different sites (tongue tip, tongue lateral, circumvallate papilla and soft palate) in oral cavity. The results were as follows; 1. The electrical taste threshold showed a tendency to decrease in the OLP group. 2. The electrical taste threshold showed a tendency to decrease in female group, but showed a tendency to increase in male group of the OLP group. 3. The electrical taste threshold showed a tendency to increase in tongue tip, tongue lateral of the multiple OLP group, but showed a tendency to decrease in circumvallate papilla, soft palate of the multiple OLP group. 4. The electrical taste threshold showed a tendency to increase in tongue tip, tongue lateral of the acute OLP group, but showed a tendency to decrease in circumvallate papilla, soft palate of the acute OLP group. 5. After treatment, electrical taste threshold was significant lower in soft palate of the OLP group than control group. 6. After treatment, NAS was significantly lower in soft palate of the OLP group than control group.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.32 no.10
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• pp.46-52
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• 2004

A design methodology of the redundancy management for a duplex FBW flight control system is introduced. A statistical analysis is applied to determine two design parameters in CCM(Cross Channel Monitor), threshold and persistence count. An analytic redundancy, which is implemented using a Kalman filtering algorithm is considered. The application of an analytic redundancy to the FCS design of the smart UAV has several advantages of increasing the aircraft's survivability and breaking the tie-condition for a duplex FCS. All the redundancy management algorithms are verified through the numeric simulation for the flight dynamics of the XV-15 tilt rotor.