• Journal of KIISE:Computing Practices and Letters
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• v.15 no.8
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• pp.577-581
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• 2009

Recently, various new services based on ubiquitous computing and networking have been developed. In this paper, we contrive Adaptive PIR(Pyroelectric Infrared Radiation) Detection Algorithm (APIDA), a PIR-sensor based digital signal processing algorithm, that detects the movement of an invading object by the recognition of heat change in the detection area, since the object like person or car emits heat(i.e., infrared radition), We devised APIDA as a highly reliable signal processing algorithm that increases the successful detection rate and decreases the false alarm rate in the intruding object detection. According to performance evaluation experiment, APIDA shows the successful detection rate of 90% and low false alarm in the plain area.

• Journal of the Institute of Convergence Signal Processing
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• v.19 no.4
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• pp.192-198
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• 2018

Recently, the use of drone has been increasing rapidly in many ways. A drone can capture remote objects efficiently so it is suitable for surveillance and security systems. This paper discusses three methods for detecting moving vehicles using a drone. We compare three target detection methods using a background frame, preceding frames, or moving average frames. They are subtracted from a current frame. After the frame subtraction, morphological filters are applied to increase the detection rate and reduce the false alarm rate. In addition, the false alarm region is removed based on the true size of targets. In the experiments, three moving vehicles were captured by a drone, and the detection rate and the false alarm rate were obtained by three different methods and the results are compared.

• Journal of Aerospace System Engineering
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• v.17 no.1
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• pp.68-78
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• 2023

In this paper, improvement measures were studied for false alarm (abnormal lighting) of emergency hydraulic warning light due to RF radiation signals in aircraft. When the warning lamp of the emergency hydraulic system is lit during flight due to electromagnetic interference caused by RF radiation signals, it affects flight mission and safety which can result in efficiency degradation and maintenance of flight mission. For false alarm of emergency hydraulic warning light, root cause analysis and troubleshooting were carried out. By shielding a composite strip under fuselage of the aircraft located in the path of the RF radiation signal, the RF radiation signal flowing into the emergency hydraulic indicator was blocked. Results of applying the improvement method through ground and flight monitoring were also described.

• Journal of KIISE:Computing Practices and Letters
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• v.14 no.1
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• pp.111-115
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• 2008

We present a simple and effective method to reduce loop-related false alarms raised by buffer-overrun static program analyzer. Interval domain buffer-overrun analyzer raise many false alarms in analyzing programs that frequently use loops and arrays. Firstly, we classified patterns of loop-related false alarms for loop-intensive programs, such as embedded programs or mathematical libraries. After that we designed a simple and effective false alarm refiner, specialized for the loop-related false alarms we classified. After the normal analysis of program in which alarms considered as false. We implemented this method on our buffer-overrun analyzer with the result that our refinement method decreased the number of false alarms by 32% of total amount the analyzer reported.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.5
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• pp.39-44
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• 2011

Automatic fire alarm system is set up to automatically detect fire on buildings. Because of economic reasons, P-type receiver and a conventional type fire detector is normally used for automatic fire alarm system in Korea. Because early detection of fire is regarded as important, the need of finding technique of fire location increases. This paper is studied a method to improve a reliability and add a function of fire location detection on a conventional type fire detector and P-type receiver. Fire location is detected by a method that controller attached on the receiver and the detector is read with a time lag. A reliability of fire detection alarm system is improved with a method that false fire alarm is able to decrease using two different principle detector together. This paper is studied for basic data of improvement of low-cost addressable automatic fire alarm system.

• The Journal of the Acoustical Society of Korea
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• v.21 no.4
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• pp.380-386
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• 2002

Conventional post-processing as like confidence measure (CM) proposed by Rahim calculates phones' CM using the likelihood between phoneme model and anti-model, and then word's CM is obtained by averaging phone-level CMs[1]. In conventional method, CMs of some specific keywords are tory low and they are usually rejected. The reason is that statistics of phone-level CMs are not consistent. In other words, phone-level CMs have different probability density functions (pdf) for each phone, especially sri-phone. To overcome this problem, in this paper, we propose normalized confidence measure. Our approach is to transform CM pdf of each tri-phone to the same pdf under the assumption that CM pdfs are Gaussian. For evaluating our method we use common keyword spotting system. In that system context-dependent HMM models are used for modeling keyword utterance and contort-independent HMM models are applied to non-keyword utterance. The experiment results show that the proposed NCM reduced FAR (false alarm rate) from 0.44 to 0.33 FA/KW/HR (false alarm/keyword/hour) when MDR is about 8%. It achieves 25% improvement of FAR.

• Journal of Korean Society of Transportation
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• v.22 no.6
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• pp.77-88
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• 2004

This study aims at developing the model that is able to detect the compression wave, which is included as a similar situation in incidents, that causes false applicable to the similar character such as incidents in the incident detection model for expressways. In this study, it has been checked whether the number of false alarms is decreased or not by modularizing this model for being able to applicable to other models such as DES and DELOS, etc. which do not perform the compression wave test based on the compression wave test process of APID model which has been being used in the expressway traffic management system currently. The evaluation in this study focuses on the sensitivity of the model and the results analysis is performed classified by each polling cycle. And how well these models are working is evaluated by each polling cycle. In addition to this, the detection rate, the false alarm rate and the average detection time in both the existing models and the model in this study are calcuated. As a result of appling the model in this study, it is found that the false alarm rate is improved through the reasonable decrease in the number of false alarm frequencies and there are not remarkable changes concerning the detection rate and the average detection time. To sum up, it is expected that a good number of improvement effects will be occurred when this model is applied to the actual expressway traffic management system.

• Fire Science and Engineering
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• v.22 no.4
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• pp.42-49
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• 2008

This research is to provide a scheme for an automatic fire alarm system with higher reliability through solving problems of malfunctioning (false or missing fire alarm) and power interruption (result from frequently unwanted activation, etc) of an automatic fire alarm system. A digital control system with microprocessor-based is proposed to reduce the possibility of malfunctioning through a combinational use of heat, smoke and CO sensors. Higher reliability could be achieved by these multiple sensors based fire detection system and fire distinction algorithm. In this research, we implemented actual fire detection system and conducted fire test to verify improvement on reliability.

• Journal of Satellite, Information and Communications
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• v.8 no.4
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• pp.89-94
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• 2013

This paper presents color video flame detection algorithm based on wavelet transform to remove detection of flickering non-flame objects. Conventional flame detection algorithms consist of simple or mixed functions using colors, temporal and spatial characteristics. But those algorithms detect non-flame objects as flame regions sometimes. False alarm reasons are flame-like objects with regular flickering lights such as car signal lamps, alarm lights etc. The proposed algorithm is to reduce false detection which is occurred in periodic flickering lights. At first, It segments the candidate flame regions by using frame difference, flame colors. Then it distinguish flame regions and non flame regions including flickering car lights by analyzing wavelet coefficients. Computer simulation results showed that the proposed algorithm removes false detection due to the periodic flickering lamps by performing 97.9% of correct detection rate while false detection rate is 7.3%.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.5A
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• pp.527-536
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• 2004

A novel hybrid multiple access system, TD-BCDMA, where Binary CDMA that maintains a constant amplitude by clipping the summation of input signals multiplied by the orthogonal codes is transmitted over a TDMA frame structure, was Nosed. In every time slot of TDMA, binary CDMA modulated multiple channel signals are transmitted with the same waveform of TDMA. TD-BCDMA has all the advantages of TDMA. Flexible adjustment of the data transmission rate In demand is possible by adjusting the number of codes and time slots assigned to each user. This property was used to show an example of Ad Hoc network applications. To obtain a proper synchronization scheme for TD-BCDMA, the Receiver Operating Characteristics performance and the false alarm probability and false dismissal probability under various channel environment of two different schemes, a preamble scheme as in TDMA and a synchronization channel scheme as in CDMA were compared. It was proved that the preamble scheme is more practical and suitable than the synchronization channel scheme for the hybrid multiple access system.