• The Journal of the Korea institute of electronic communication sciences
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• v.17 no.1
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• pp.139-146
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• 2022

Mountain accidents such as forest fires and missing people are increasing as hikers increase due to indoor activities restrictions caused by the prolonged COVID-19 incident. If a dangerous situation occurs at outside where rescue workers cannot reach, the search time for person can be reduced using a quadcopter. Considering this, in this paper, Multiwii is used to smoothly hover the quadcopter by setting optimized PID values of the x-axis, y-axis, and z-axis (Yaw) according to the change in the inclination of the gas. In addition, after installing Open CV on Raspberry Pie, the camera uses HSV color space to filter the color such as the description of the person, and uses a thermal imaging camera to receive thermal sensing images in real time in environments where color extraction is difficult. As a result, it was confirmed that hovering was possible at a height of 2 to 8 m, blue extraction was possible at a height of 5 m, and heat detection was possible at a distance of less than 10 cm.

• The korean journal of orthodontics
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• v.34 no.6 s.107
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• pp.497-505
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• 2004

The purpose of this study was to evaluate the post-retention stability of the lower incisor axis in Class II division 2 malocclusions. The dental casts and lateral cephalograms from before (T1) and after (T2) orthodontic treatment and long-term post-retention (T3) in 62 Class II division 2 malocclusion cases were included in this study. After several linear and angular measurements at each time were taken, the significance in the amount of change of the lower incisor axis for each gender and extraction versus non-extraction was evaluated. The results showed that the lower incisors that inclined labially during treatment were unstable and relapsed to the original lingual position in Class II division 2 malocclusions (p<0.001). There was no significant difference between extraction and non-extraction groups for the amount of lingual relapse of the lower incisors (p>0.05). There was no significant difference between male and female groups for the axial change of the lower incisors (p>0.05). As a result of multiple regression analysis, the cephalometric measurement best predicting the lower incisor position to the A-Pog line post-retention was pre-treatment L1-Apog(mm) and pre-treatment SNGoMe$(^{\circ})$. Because of the instability of labially inclined lower incisors after orthodontic treatment, the treatment goal should be the pre-treatment incisor axial position.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.763-766
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• 2003

A direct parameter extraction method using several two-port parameter equations derived in cutoff and active bias modes has been studied to obtain an accurate Gummel-Poon BJT model. First, dc model parameters were extracted from slopes and y-axis intercepts of I-V curve and Gummel plot. The pad capacitances and junction capacitance parameters were determined by using measured S-parameter sets in the cutoff bias. The resistance and transit time parameters were extracted by using measured S-parameter sets in the active bias.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.5
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• pp.432-437
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• 2008

This paper proposes a defect cell extraction algorithm for TFT-LCD auto-repair system. Auto defect search algorithm and automatic defect cell extraction method are very important for TFT-LCD auto repair system. In the previous literature[1], we proposed an automatic visual inspection algorithm of TFT-LCD. Based on the inspected information(defect size and defect axis, if defect exists) by the automatic search algorithm, defect cells should be extracted from the input image for the auto repair system. For automatic extraction of defect cells, we used a novel block matching algorithm and a simple filtering process in order to find a given reference point in the LCD cell. The proposed defect cell extraction algorithm can be used in all kinds of TFT-LCD devices by changing a stored template which includes a given reference point. Various experimental results show the effectiveness of the proposed method.

• Journal of rehabilitation welfare engineering & assistive technology
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• v.5 no.1
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• pp.87-93
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• 2011

This paper proposes a method for extraction of the gaze point on display using EOG(Electrooculography) signal. Based on the linear property of EOG signal, the proposed method corrects scaling difference, rotation difference and origin difference between coordinate of using EOG signal and coordinate on display, without adjustment using the head movement. The performance of the proposed method was evaluated by measuring the difference between extracted gaze point and displayed circle point on the monitor with 1680*1050 resolution. Experimental results show that the average distance errors at the gaze points are 3%(56pixel) on x-axis, 4%(47pixel) on y-axis, respectively. This method can be used to human computer interface of pointing device for general paralysis patients or HCI for VR game application.

• Journal of Information Processing Systems
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• v.16 no.1
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• pp.155-170
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• 2020

Passive ranging is a critical part of machine vision measurement. Most of passive ranging methods based on machine vision use binocular technology which need strict hardware conditions and lack of universality. To measure the distance of an object placed on horizontal plane, we present a passive ranging method based on monocular vision system by smartphone. Experimental results show that given the same abscissas, the ordinatesis of the image points linearly related to their actual imaging angles. According to this principle, we first establish a depth extraction model by assuming a linear function and substituting the actual imaging angles and ordinates of the special conjugate points into the linear function. The vertical distance of the target object to the optical axis is then calculated according to imaging principle of camera, and the passive ranging can be derived by depth and vertical distance to the optical axis of target object. Experimental results show that ranging by this method has a higher accuracy compare with others based on binocular vision system. The mean relative error of the depth measurement is 0.937% when the distance is within 3 m. When it is 3-10 m, the mean relative error is 1.71%. Compared with other methods based on monocular vision system, the method does not need to calibrate before ranging and avoids the error caused by data fitting.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.160-161
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• 2010

In this paper, trademark image retrieval system is proposed by using color information and shape information. We use the image for a color information by dividing into the area and extracting the area color distribution histogram. We use for the shape information by preprocessing of the boundary extraction, the centroid extraction, angular sampling etc. and calculating of the sum of the distance from the centroid to the boundary, the standard deviation, and the rate of long axis to short axis. In particular, centroid by using the angular sampling can extract feature and reduce the processing time. Users can perform searchs using the color and shape information, and also the two methods by mixing can be used by weighting.

• The korean journal of orthodontics
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• v.17 no.2
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• pp.321-333
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• 1987

The purpose of this study was to observe the changes of the lower 3rd molars following the extraction of the lower 2nd molars by Lateral Cephalograms and Orthopantomograms. The subjects consisted of twenty malocclusion, 7 males 13 females, were 19 year 5 month old at the removal of the lower 2nd molars, 19 year 1 month old at the end of the orthodontic supervision after the removal of the lower 2nd molars (mean age) The obtained results were as follows, 1 It is recommended to extract the lower 2nd molars when the lower 3rd molars are Nolla's Stage 4 or 5 2 With the pre-extraction variables obtained by factor analysis, it was possible to predict the long axis of the lower 3rd molars after 2nd molar extraction. 3 There were no impacted 3rd molars.

• The Korea Journal of Herbology
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• v.25 no.2
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• pp.117-128
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• 2010

Objectives : In this study the antidepressant effects of mixture of Citri Peticulatae Viride Pericarpium and Lycii Radicis Cortex on the change of HPA-Axis and Catecholamic system was investigated Methods : The forced swimming test(FST) was performed. The expression of corticotropin-releasing factor(CRF), c-Fos in the paraventricular nucleus(PVN), and tyrosine hydroxylase(TH) in the ventral tegmental area(VTA) and locus coeruleus(LC) was measured with immunohistochemical method and the concentration of seum adrenocorticotropic hormone(ACTH) was measured with ELISA method. And the experimental groups were divided into the extraction after mixing(A) and mixture after extraction(B). The effects of both group were compared. Results : The duration of immobility in the forced swimming test was significantly decreased in the A400 group(P<0.01). The expression of CRF in PVN were significantly reduced in the A100, A400, B100, B400groups(P<0.001). but the expression of c-fos in PVN weren't reduced in all groups. And the concentration of ACTH in Plasma were significantly reduced in the A 100 group(P<0.01). The expression of TH in LC were significantly reduced in the A 400, B 100 and B400 groups(P<0.05~P<0.01). Conclusion : Mixture of Citri Peticulatae Viride Pericarpium and Lycii Radicis Cortex has antidepressant effects. But the difference between mixing and extracting methods was not shown.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.137-143
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• 2018

DICOM images of patellofemoral bones were converted into a stereolithography file, and a Unigraphics CAD program was used to create a CAD modeling in which there exists point, line and facet information. The modeling extraction of joint facets was performed by linking two adjacent points into lines in the stereolithography file by using the Unigraphics rapid spacing function and then linking the lines into facets to complete the entire modeling. This modeling extraction was performed based on the anatomical knowledge of joint facet directions. As a result, a personalized space modeling and solid modeling were produced for the joint facets of patellofemoral bones. This was followed by a CAM control computing operation of solid modeling on graphite materials and 5-axis machining of patellofemoral bones. That is the description of a method for a personalized implant modeling by using DICOM images of patellofemoral bones.