• The Journal of Society for e-Business Studies
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• v.23 no.2
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• pp.111-121
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• 2018

Many problems in rotating machinery such as aircraft engines, wind turbines and motors are caused by bearing defects. The abnormalities of the bearing can be detected by analyzing signal data such as vibration or noise, proper pre-processing through a few signal processing techniques is required to analyze their frequencies. In this paper, we introduce the condition monitoring method for diagnosing the failure of the rotating machines by analyzing the vibration signal of the bearing. From the collected signal data, the normal states are trained, and then normal or abnormal state data are classified based on the trained normal state. For preprocessing, a Hamming window is applied to eliminate leakage generated in this process, and the cepstrum analysis is performed to obtain the original signal of the signal data, called the formant. From the vibration data of the IMS bearing dataset, we have extracted 6 statistic indicators using the cepstral coefficients and showed that the application of the Mahalanobis distance classifier can monitor the bearing status and detect the failure in advance.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.48 no.4
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• pp.107-115
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• 2011

In this paper, we proposed fast and efficient algorithm for detecting near-duplication based on content based retrieval in large scale video database. For handling large amounts of video easily, we split the video into small segment using scene change detection. In case of video services and copyright related business models, it is need to technology that detect near-duplicates, that longer matched video than to search video containing short part or a frame of original. To detect near-duplicate video, we proposed motion distribution and frame descriptor in a video segment. The motion distribution descriptor is constructed by obtaining motion vector from macro blocks during the video decoding process. When matching between descriptors, we use the motion distribution descriptor as filtering to improving matching speed. However, motion distribution has low discriminability. To improve discrimination, we decide to identification using frame descriptor extracted from selected representative frames within a scene segmentation. The proposed algorithm shows high success rate and low false alarm rate. In addition, the matching speed of this descriptor is very fast, we confirm this algorithm can be useful to practical application.

• Design & Manufacturing
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• v.14 no.1
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• pp.8-14
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• 2020

In general, auto parts production assembly line is assembled and produced by automatic mounting by an automated robot. In such a production site, quality problems such as misalignment of parts (doors, trunks, roofs, etc.) to be assembled with the vehicle body or collision between assembly robots and components are often caused. In order to solve such a problem, the quality of parts is manually inspected by using mechanical jig devices outside the automated production line. Automotive inspection technology is the most commonly used field of vision, which includes surface inspection such as mounting hole spacing and defect detection, body panel dents and bends. It is used for guiding, providing location information to the robot controller to adjust the robot's path to improve process productivity and manufacturing flexibility. The most difficult weighing and measuring technology is to calibrate the surface analysis and position and characteristics between parts by storing images of the part to be measured that enters the camera's field of view mounted on the side or top of the part. The problem of the machine vision device applied to the automobile production line is that the lighting conditions inside the factory are severely changed due to various weather changes such as morning-evening, rainy days and sunny days through the exterior window of the assembly production plant. In addition, since the material of the vehicle body parts is a steel sheet, the reflection of light is very severe, which causes a problem in that the quality of the captured image is greatly changed even with a small light change. In this study, the distance between the car body and the door part and the door are acquired by the measuring device combining the laser slit light source and the LED pattern light source. The result is transferred to the joint robot for assembling parts at the optimum position between parts, and the assembly is done at the optimal position by changing the angle and step.

• Tuberculosis and Respiratory Diseases
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• v.40 no.5
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• pp.558-564
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• 1993

Background: Gallium scans was used clinically for detection of inflammatory lesion, granulomatous process and neoplasm and inflammatory activity in interstitial disease. So we had perfomed $Ga^{67}$ scan to see the finding of $Ga^{67}$ scan in miliary tuberculosis and to correlate $Ga^{67}$ uptake with that of the chest PA and the clinical severity. Method: We examined 10 patients who were confirmed as having miliary tuberculosis, with $Ga^{67}$ scan, chest PA and arterial blood gas analysis. Results: 1) Diffuse, positive gallium uptake was seen in all cases of miliary tuberculosis. 2) In most of cases, gallium uptake was noted only at the lung field in spite of hematogenous spread of tuberculous foci. 3) The strong correlation between chest PA and $Ga^{67}$ scan finding was seen. 4) The intimate correlation between arterial hypoxemia and $Ga^{67}$ scan finding was also noted. Conclusion: Gallium scan showed diffuse pulmonary uptake in all cases of miliary tuberculosis and it may provid a useful information to assess the disease severity in miliary tuberculosis.

• Journal of the Korea Convergence Society
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• v.9 no.9
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• pp.183-189
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• 2018

This study deals with the design and development of imaging optics having 24mm focal length for MWIR ($3{\sim}5{\mu}m$) with two symmetrical lenses facing each other. We used CodeV in our optical design, and we performed the optimization process to have the resolution and angle of view satisfying the user's requirements. The materials of lenses were limited to two types, including KCIR035 with a refractive index of 1.7589, developed in Korea. The optical system designed in this way consists of two aspherical lenses made of KCIR035 material having the same shape and one spherical lens made of Si. Here, the arrangement of the two aspherical lenses is characterized by having a symmetrical structure facing each other. And this optical system has a resolution of MTF value of 0.35 or more at a line width of 20 lp / mm. Therefore, it is considered that this optical system has the capability to be applied to a thermal imaging camera using a $206{\times}156$ array MWIR detection device having a pixel size of $25{\mu}m$.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.12 no.6
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• pp.619-628
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• 2019

In this paper, we designed a beta ray sensor for a true random number generator. Instead of biasing the gate of the PMOS feedback transistor to a DC voltage, the current flowing through the PMOS feedback transistor is mirrored through a current bias circuit designed to be insensitive to PVT fluctuations, thereby minimizing fluctuations in the signal voltage of the CSA. In addition, by using the constant current supplied by the BGR (Bandgap Reference) circuit, the signal voltage is charged to the VCOM voltage level, thereby reducing the change in charge time to enable high-speed sensing. The beta ray sensor designed with 0.18㎛ CMOS process shows that the minimum signal voltage and maximum signal voltage of the CSA circuit which are resulted from corner simulation are 205mV and 303mV, respectively. and the minimum and maximum widths of the pulses generated by comparing the output signal through the pulse shaper with the threshold voltage (VTHR) voltage of the comparator, were 0.592㎲ and 1.247㎲, respectively. resulting in high-speed detection of 100kHz. Thus, it is designed to count up to 100 kilo pulses per second.

• Journal of Broadcast Engineering
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• v.13 no.4
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• pp.427-439
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• 2008

This paper proposes a novel method to convert monoscopic soccer videos to stereoscopic videos. Through the soccer video analysis process, we detect shot boundaries and classify soccer frames into long shot or non-long shot. In the long shot case, the depth mapis generated relying on the size of the extracted ground region. For the non-long shot case, the shot is further partitioned into three types by considering the number of ground blocks and skin blocks which is obtained by a simple skin-color detection method. Then three different depth assignment methods are applied to each non-long shot types: 1) Depth estimation by object region extraction, 2) Foreground estimation by using the skin block and depth value computation by Gaussian function, and 3)the depth map generation for shots not containing the skin blocks. This depth assignment is followed by stereoscopic image generation. Subjective evaluation comparing generated depth maps and corresponding stereoscopic images indicate that the proposed algorithm can yield the sense of depth from a single view images.

• Korean Journal of Microbiology
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• v.48 no.4
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• pp.309-313
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• 2012

The purpose of this study is to simultaneously detect and identify specific genus of Lactobacillus distributed in vagina of healthy women in their twenties by using multiplex primer. Vaginal fluid samples were taken from 166 women who were healthy and did not have vaginosis symptoms caused by bacterial infection. Six species of lactic acid bacteria belong to Lactobacillus genus that are known to inhabit in healthy vagina were selected to make a species-specific multiplex primer. Multiplex primer I was specified to selectively detect L. iners, L. crispatus, L. gasseri and multiplex primer II was specified to selectively detect L. acidophilus, L. jensenii, L. fermentum. L. crispatus (77%) was most frequently detected, and L. acidophilus (57%) and L. jensenii (57%) were relatively higher than others. Although the proportion of L. iners (59%) was a little higher than those of L. acidophilus and L. jensenii, this should be further validated in healthy women's vagina to be sure since they often appear in women having bacterial vaginosis and/or during the antibiotic therapy. Conclusively, the multiplex PCR technique using the species-specific primer could a useful tool to predict variation of vaginal health condition and process of recovery from vaginal disease.

• Restorative Dentistry and Endodontics
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• v.25 no.4
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• pp.509-526
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• 2000

It is known that injuries to the dentin have a corresponding inflammatory effect on the pulp and these inflammatory effects frequently result in pulpal pathoses due to progressive degradation of pulpal connective tissue. It was supposed that the tissue degradation in different inflammatory process was controlled by proteinase activity and antiproteinase activity. Therefore, the purpose of this study was to examine the pulp and periapical pathoses in terms of the activities of proteinase and proteinase inhibitor, 37 pulpal tissues were divided by clinical diagnostic criteria into normal pulp, acute inflamed pulp, and chronic inflamed pulp, and then those groups were subdivided by histopathological findings into 5 pulpal pathoses groups, i.e. normal pulp (P1, n=8), chronic pulpitis with fibrotic change (P2, n=2), chronic pulpitis with dystrophic calcification (P3, n=11), chronic pulpitis with pulp abscess (P4, n=7), acute pulpitis with necrotic change (P5, n=4), 26 periapical tissues were also divided by ordinary histopathological findings into 3 periapical pathoses group, i.e., granuloma (A1, n=17), cyst (A2, n=2) and abscess (A3, n=7). The activities of proteinases (cathepsin G, MMP-3) and proteinase inhibitors (${\alpha}1$-AT, TIMP-1 and, SLPI) were evaluated by RT-PCR and immunohistochemical methods. The results were as follows. 1. Generally, the intensity of immunohistochemical staining of proteinases and proteinase inhibitors increased in P2 and P5 groups compared to P1 group. 2. The immunohistochemical stain of proteinases and proteinase inhibitors was intensely detected in P2 group, showing low inflammatory reaction and low tissue degradation, but it was reduced in P3 and P4 groups, showing severe tissue degradation. 3. The distribution of proteinases and proteinase inhibitors in pulpal pathoses was consistently presented by immunohistochemical staining, while the expression of proteinase and/or proteinase inhibitors mRNAs in pulpal pathoses was occasionally detected by RT-PCR methods. 4. RT-PCR of proteinase and proteinase inhibitors was usually positive in P2, showing rare tissue degradation, but it was almost negative in P3 and P4, showing severe tissue degradation. 5. We presume that the reason why the level of proteinase and proteinase inhibitors was so sparse in RT-PCR method is due to the abrupt decrease of mRNA synthesis or degradation of synthesized mRNA of proteinase and/or proteinase inhibitors depend on the inflammatory reaction and/or on the degradation of pulp tissues(P3, P4). 6. Pulpal pathoses groups showed significant lower RT-PCR detection of proteinases and proteinase inhibitors than the periapical pathoses group(p<0.05), and there is no significant difference among the periapical pathoses groups(p>0.05).

• Journal of KIISE
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• v.42 no.4
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• pp.434-441
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• 2015

Next generation memory technologies, which we denote as 'new memory', have both non-volatile and byte addressable properties. These characteristics are expected to bring changes to the conventional computer system structure. In this paper, we propose a fast boot technique for hybrid main memory architectures that have both new memory and DRAM. The key technique used for fast booting is write-tracking. Write-tracking is used to detect and manage modified data detection and involves setting the kernel region to read-only. This setting is used to trigger intentional faults upon modification requests. As the fault handler can detect the faulting address, write-tracking makes use of the address to manage the modified data. In particular, in our case, we make use of the MMU (Memory Management Unit) translation table. When a write occurs to the boot completed state, write-tracking preserves the original state of the modified address of the kernel region to a particular location, and execution continues. Upon booting, the fast booting process restores the preserved data to the original kernel region allowing rapid system boot-up. We develop the fast booting technique in an actual embedded board equipped with new memory. The boot time is reduced to less than half a second compared to around 15 seconds that is required for the original system.