• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.4
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• pp.500-507
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• 2009

This paper presents a novel method which can detect a target in IR image for active protection system. The target in IR image for the active protection system is small, moreover it moves with enormous speed. The proposed algorithm is comprised of robust clutter rejection methods and target optimized detection algorithms for small target, and an advanced method of selecting a final target position in target area, it can work in some milliseconds. The proposed algorithm provides the active protective system with more correct positions than those of radar, so that helps the active protection system can defense all threats with the utmost precision.

• Journal of the Korea Institute of Military Science and Technology
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• v.14 no.1
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• pp.123-131
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• 2011

In this paper, modeling and design of a distributed detection system are considered for an active sonar sensor network. The sensor network has a parallel configuration and it consists of a fusion center and a set of receiver nodes. A system with two receiver nodes is considered to investigate a theoretical aspect of design. To be specific, AND rule and OR rule are considered as the fusion rules of the sensor network. For the fusion rules, it is shown that a threshold rule of each sensor node has uniformly most powerful properties. Optimum threshold for each sensor is obtained that maximizes the probability of detection given probability of false alarm. Numerical experiments were also performed to investigate the detection characteristics of a distributed detection system with multiple sensor nodes. The experimental results show how signal strength, false alarm probability, and the distance between nodes in a sensor field affect the system detection performances.

• Fire Science and Engineering
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• v.16 no.4
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• pp.28-32
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• 2002

The performance based design in fire detection system, the effect of high airflow and dilution of smoke produced in any fire situation serve to increase the response time of point-type smoke detectors. This study investigated the smoke density of ceiling, under the air stream and in normal status when fire type is smoldering fires. The result of study, smoke generated in the fire was swept away from nearby spot type smoke detector which failed to actuate because dispersed in diluted form around the room. The concept of performance based design in fire detection system of protected area influenced by high airflow provided the need of active fire detection system such as air sampling smoke detection system.

• Korean Journal of Remote Sensing
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• v.36 no.5_1
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• pp.775-784
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• 2020

Recent global warming and anthropogenic activities have caused more frequent and massive wildfires with longer durations and more significant damages. MODIS has been monitoring global wildfires for almost 20 years, and GK2A and Himawari-8 are observing the wildfires in East Asia 144 times a day. However, the spatial resolution of 1 to 2 km is not sufficient for the detection of small and medium-size active fires, and therefore the studies on the active fire detection using high-resolution images are essential. However, there is no official product for the high-resolution active fire detection. Hence, we implemented the active fire detection algorithm of Landsat 8 and carried out a high-resolution-based detection of active fires in Australia in 2019, followed by the comparisons with the products of Himawari-8 and MODIS. Regarding the intense fires, the three satellites showed similar results, whereas the weak igniting and extinguishing fires or the fires in narrow areas were detected by only Landsat 8 with a 30m resolution. Small-sized fires, which are the majority in Korea, can be detected by the high-resolution satellites such as Landsat 8, Sentinel-2, Kompsat-3A, and the forthcoming Kompsat-7. Also, a comprehensive analysis together with the geostationary satellites in East Asia such as GK2A, Himawari-8, and Fengyun-3 will help the interoperability and the improvement of spatial and temporal resolutions.

• Women's Health Nursing
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• v.16 no.2
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• pp.126-136
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• 2010

Purpose: This study was done to evaluate factors affecting active early detection behaviors of breast cancer and performance rate of breast self examination (BSE), physical examination and mammography. Methods: The participants were 264 women from an outpatient breast clinic of a university hospital and materials were collected from March 2007 to February 2008 using a structured questionnaire. The data were analyzed using $x^2$ test, logistic analysis. Results: The rate for BSE was 58.3%, for physical examination, 55.3% and for mammography experience, 63.4%. Women with all of these active early detection behaviors accounted for 31.8% of the participants. Various factors such as age, income, marital status, and menopause showed increased significant performance rate. The explanation power of logistic model was 48.5%, and was significant for age, income and health belief. Factors related to high performance rate were being over 40 years of age, high income and high health belief score. Conclusion: Active early detection behaviors were not high in spite of marked increases in breast cancer incidence. Encouragement for women practicing early detection behavior is important, but there is also a need to develop interest and support for the low performance group. More sustained education and public relations are needed to further improve active early detection behavior.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.08a
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• pp.268.1-268.1
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• 2013

Immobilization of conducting nanoparticles on a nanogap comprising two electrodes spaced at a distance comparable to the particle size can be used as a simple and sensitive method of detecting the particles. In this work, we have examined the performance of the nanogap devices in the measurement of metallic nanoparticles, particularly gold nanoparticles (Au NPs). Detection of pM-level Au NPs in an aqueous suspension was quite straightforward irrespective of the existence of non-conducting materials. Speed of detection or the time necessary for the completion of the measurement, however, was strongly dependent upon the immobilization process. Active trapping process was found to be much more efficient and also effective in the detection of nanoparticles than its passive counterpart.

• Proceedings of the KIPE Conference
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• 2001.10a
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• pp.475-479
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• 2001

Compensation characteristics or active filters based on voltage detection are investigated. These active filters act equivalently as a passive circuit so that they may not cause practical problems such as stimulation of resonance in the distribution lines. Thus, these active filters can be used as the general-purpose active filters. On the other hand, these active filters may have a possibility of the anti-resonance associated with the line inductance of the distribution lines. In this paper, the relationship between the anti-resonance and the control parameters of the proposed active filters is clarified. Some methods to avoid the problems due to the anti-resonance are investigated. Experimental results are included to confirm the validity of the investigation presented in this paper.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.10 no.12
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• pp.5507-5528
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• 2016

In computer vision, salient object is important to extract the useful information of foreground. With active contour analysis acting as the core in this paper, we propose a bottom-up saliency detection algorithm combining with the Bayesian model and the global color distribution. Under the supports of active contour model, a more accurate foreground can be obtained as a foundation for the Bayesian model and the global color distribution. Furthermore, we establish a contour-based selection mechanism to optimize the global-color distribution, which is an effective revising approach for the Bayesian model as well. To obtain an excellent object contour, we firstly intensify the object region in the source gray-scale image by a seed-based method. The final saliency map can be detected after weighting the color distribution to the Bayesian saliency map, after both of the two components are available. The contribution of this paper is that, comparing the Harris-based convex hull algorithm, the active contour can extract a more accurate and non-convex foreground. Moreover, the global color distribution can solve the saliency-scattered drawback of Bayesian model, by the mutual complementation. According to the detected results, the final saliency maps generated with considering the global color distribution and active contour are much-improved.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2009.06a
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• pp.575-576
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• 2009

• Journal of the Korea Institute of Information and Communication Engineering
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• v.17 no.1
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• pp.127-136
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• 2013

The islanding detection and prevention function in the important performance of the grid-connected inverter is the essential details which should be considered for worker's safety to maintain the system. This paper tries to suggest the active frequency shake islanding detection technique in the grid-connected PV generation system using sunlight. The existing active frequency drift method algorithm is described to suggest active frequency shake method algorithm. And, the algorithm which can reduce the non-detection zone, improve THD, and improve the detection speed in comparison with the existing algorithm is suggested. And we applied the proposed algorithm to the 3kW grid-connected photovoltaic inverter generation and verified the feasibility of the technique through the simulation and experiments.