• Journal of the Institute of Electronics Engineers of Korea SP
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• v.40 no.5
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• pp.312-321
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• 2003

In this paper, we implement robot which are ability to recognize obstacles and moving automatically to destination. we present two results in this paper; hardware implementation of image processing board and software implementation of visual feedback algorithm for a self-controlled robot. In the first part, the mobile robot depends on commands from a control board which is doing image processing part. We have studied the self controlled mobile robot system equipped with a CCD camera for a long time. This robot system consists of a image processing board implemented with DSPs, a stepping motor, a CCD camera. We will propose an algorithm in which commands are delivered for the robot to move in the planned path. The distance that the robot is supposed to move is calculated on the basis of the absolute coordinate and the coordinate of the target spot. And the image signal acquired by the CCD camera mounted on the robot is captured at every sampling time in order for the robot to automatically avoid the obstacle and finally to reach the destination. The image processing board consists of DSP (TMS320VC33), ADV611, SAA7111, ADV7l76A, CPLD(EPM7256ATC144), and SRAM memories. In the second part, the visual feedback control has two types of vision algorithms: obstacle avoidance and path planning. The first algorithm is cell, part of the image divided by blob analysis. We will do image preprocessing to improve the input image. This image preprocessing consists of filtering, edge detection, NOR converting, and threshold-ing. This major image processing includes labeling, segmentation, and pixel density calculation. In the second algorithm, after an image frame went through preprocessing (edge detection, converting, thresholding), the histogram is measured vertically (the y-axis direction). Then, the binary histogram of the image shows waveforms with only black and white variations. Here we use the fact that since obstacles appear as sectional diagrams as if they were walls, there is no variation in the histogram. The intensities of the line histogram are measured as vertically at intervals of 20 pixels. So, we can find uniform and nonuniform regions of the waveforms and define the period of uniform waveforms as an obstacle region. We can see that the algorithm is very useful for the robot to move avoiding obstacles.

• Journal of the Korean Geotechnical Society
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• v.35 no.11
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• pp.25-36
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• 2019

The safety barrier is installed on road embankment to prevent vehicles from falling into road side slope. Among the safety barrier, flexible guardrails are usually installed. The flexible guardrail generally consists of a protection cross-beam and supporting in-line piles. These guardrail piles are installed nearby slope edge of road embankment because the side area of the road is much narrow. The protection cross-beam absorbs impact energy caused by vehicle collision. The pile-soil interaction also absorbs the rest of the impact energy and then, finally, the flexible guardrail system resists the impact load. This paper aims to investigate the pile-soil interaction subjected to impact load using centrifuge model tests. In this study, a single pile was installed in compacted residual soil and loaded under lateral impact load. An impact loading system was designed and developed available on centrifuge tests. Using this loading system, a parametric study was performed and the parameters include types of loading and ground. Finally, the ultimate bearing capacity of supporting pile under impact load was analyzed using load-displacement curve and soil reaction pressure distributions at ultimate were evaluated and compared with previous studies.

• The Journal of Korean Academy of Prosthodontics
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• v.49 no.1
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• pp.22-28
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• 2011

Purpose: This article attempted to examine how teeth for restoration is made in a clinical practice and utilize it as future educational material of teeth formation and basic data for additional research. Materials and methods: This experiment investigated the models sent to milling center for production of zirconia crowns. After scanned with Lava CAD/CAM System (3M ESPE, Seefeld, Germany), they are measured on 'ImageJ (version 1.32j, National Institutes of Health, USA)' program and compared and analyzed. Convergence angle from mesio-distal surfaces and bucco-lingual surfaces of each teeth are measured. Also, bucco-lingual diameter of the region lowered as much as 0.4 mm from incisal edge in anterior teeth except canines.(This measure is defined as the Peak 0.4) The analysis of data between each group was conducted by Windows SPSS statistic program, and was proved significant on 95% confidence level by independent t-test, one-way ANOVA and multiple analysis (Sheff${\'{e}}$ test). Results: The mean value of convergence angle was $18.67^{\circ}$ It is ranked as molar ($26.70^{\circ}$) > premolar ($16.87^{\circ}$) > anterior teeth ($14.81^{\circ}$) in the order of mesio-distal convergence angle; anterior teeth ($22.32^{\circ}$) > molar ($20.93^{\circ}$) > premolar ($15.41^{\circ}$) in the order of bucco-lingual convergence angle. The mean value of Peak 0.4 was 1.18 mm. Conclusion: Convergence angle of abutment of zirconia all ceramic crown has difference depending on the location in the arch. Due to the nature of production of zirconia all ceramic crown, convergence angle of abutment and line angle finishing degree can have an effect on internal suitability of restoration.

• Journal of the Korean Society of Costume
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• v.1
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• pp.101-117
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• 1977

This thesis is a study of the Simui(深衣) system which was a dress regulation peculiar to old China with skirt and coat. The origin of Simui is a very long time, that is, before Ju dynasty in China. Its wearing range had a large circle irrespective of rank and good or bad luck. This was a ordinary dress to the Emperor or the lords, a below court attire or a below sacrificial rites attire to the illustrious officials, and good luck dress to the common people. But this was a funeral rites attire or coming-of-age ceremony attire in domestic behaviour. In the times of Song dynasty, lots of confucian scholars had put on this simui because of Juhi's recommendation for domestic behaviour. This Simui had been put on through all the times of China and was the original text of all the dress. Especially the court attire and silkworm working dress of Empress, and the court attire and underwear court attire of Emperor is also made out of this Simui, therefore this is a origin of the ceremonial dress which formed into long coat. In Korea it is said that this Simui was brought in prior to the middle of Goryeo dynasty. But we can't tell the correct transmitted age. According to the following records in Goryeo History, "King had put on the Simui as a sacrificial rite attire in the times of Yejong". It is sure that this Simui was brought in prior to the times of Yejong. In fact, lots of confucian scholars had put on the Simui since the introduction of confucianism in the end of Goryeo dynasty and after that time this was taken by many confucian scholars through Yi dynasty. Korean Simui system was complied with Chinese system through confucian domestic behaviour, This was respected for court dress of confucian scholars, as it were, Chumri, (an ordinary dress of scholars), Nansam (a uniform of upper student), and Hakchangui (a uniform of confucian student). There are many deta about Simui system in the book of Yeki, chapter Okcho and Simui, and other many canfucian books. But we didn't demonstrate the theory about it till now. Especially there are diversifies of opinions about the phrase of "Sok Im Ku Byun" in Yeki. Simui was cut in separate and then was stitched together in one piece. Generally its shape had round sleeve and angled lapel, its length reaches to the anklebone. And it has a line around the lapel, the sleeve band, and the edge of skirt. It is called Simui because the body can be wrapped deeply in broad width and large sleeve. The Simui was made of white fine linen and was cut by the natural size of body. Every part of Simui had a profound meaning; the round sleeve in compliance with regulation can keep a courtesy when a walker moves his hands and the angled lapel like a carpenter's square in compliance with square keeps them front loosing their Justice and a string of the back also keeps them loosing from their righteousness and the flat lower part of Simui makes their heart and mind calm. This Simui was usually attendant on a head cover and belt made cloth, and black shoes. This thesis was made a study of documents and portrait from Yi dynasty, for the actual object was not obtained.

• Journal of Conservation Science
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• v.27 no.4
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• pp.403-414
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• 2011

This study is re-creational experiment of Goryeo gold-painted decoration based on the research of the gold remaining and gold painting technique on the two pieces of Goryeo gold-painted celadon and the three pieces of Chinese gold-painted porcelain on North Song period which ones have been owned by National Museum of Korea since 2007. For the observation of glue state and color developing ability, four kinds of agglutinative agent and gold powder were mixed over the porcelain sherds, then gradually fired from $100^{\circ}C$ to $1200^{\circ}C$. Visual effect and ideal temperature were measured. Among of them, oil and glue showed the best results in glue state and color developing ability. Through those results, the entire Goryeo engraved celadon were reproduced in modern facilities. Oil and glue were gold-painted over the glaze then it was fired at the ideal temperature 700 to $800^{\circ}C$. For observation the binding condition, the gold-painting cross section was looked by the scanning electron microscope (SEM). As the result, oil and glue did not make much difference in Agglutinative agent, but gold was good, the color developing ability, however, in the case of oil, the edge of gold is curled because of its interfacial tension, and it is not dried well at room temperature so the working property is not as good as the glue. Glue more effective in terms of work efficiency, but color developing ability to fall slightly in this experiment were able to see through.

• Journal of Biomedical Engineering Research
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• v.25 no.2
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• pp.137-144
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• 2004

ECG signals are often contaminated with high-frequency noise such as muscle artifact, power line interference, and others. In the ECG signal processing, especially during a pre-processing stage, numerous noise removal techniques have been used to reduce these high-frequency noise without much distorting the original signal. This paper proposes a new type of digital filter with a continuously variable cutoff frequency to improve the signal quality This filter consists of a cutoff frequency controller (CFC) and variable cutoff frequency lowpass filter (VCF-LPF). From the noisy input ECG signal, CFC produces a cutoff frequency control signal using the signal slew rate. We implemented VCF-LPF based on two new filter design methods called convex combination filter (CCF) and weight interpolation fille. (WIF). These two methods allow us to change the cutoff frequency of a lowpass filter In an arbitrary fine step. VCF-LPF shows an excellent noise reduction capability for the entire time segment of ECG excluding the rising and falling edge of a very sharp QRS complex. We found VCF-LPF very useful and practical for better signal visualization and probably for better ECG interpretation. We expect this new digital filter will find its applications especially in a home health management system where the measured ECG signals are easily contaminated with high-frequency noises .

• Korean Journal of Remote Sensing
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• v.31 no.2
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• pp.85-99
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• 2015

TDI CCD sensors are being used for most of the electro-optical camera mounted on the low earth orbit satellite to meet high performance requirements such as SNR and MTF. However, the CMOS sensors which have a lot of implementation advantages over the CCD, are being upgraded to have the TDI function. A few methods for improving the issue of motion blur which is apparent in the CMOS sensor than the CCD sensor, are being introduced. Each pixel can be divided into a few sub-pixels to be read more than once as is the same case with three or four phased CCDs. The fill factor can be reduced intentionally or even a kind of mask can also be implemented at the edge of pixels to reduce the blur. The motion blur can also be reduced in the TDI CMOS sensor by reducing the integration time from the full line scan time. Because the integration time can be controlled easily by the versatile control electronics, one of two performance parameters, MTF and SNR, can be concentrated dynamically depending on the aim of target imaging. MATLAB simulation has been performed and the results are presented in this paper. The goal of the simulation is to compare dynamic MTFs affected by the different methods for reducing the motion blur in the TDI CMOS sensor.

• The Journal of Korean Academy of Prosthodontics
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• v.37 no.4
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• pp.454-464
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• 1999

The metal ceramic crown is currently the most popular complete veneer restoration in dentistry, but in many cases, the metal cervical collar at the facial margin is unesthetic and unacceptable. Facial porcelain margin has been used in place of it. But this dose not solve the problems, such as dark gingival discoloration and cervical opaque reflection of porcelain veneer. Recently, metal copings which were designed to terminate its labio-cervical end on the axial walls coronal to the shoulder have been clinically used to solve the esthetic problem of metal ceramic crown. But in this design, porcelain veneer of labio-cervical area which is not supported by metal may not be able to resist the stress during cementation and mastication. The purpose of this study was to evaluate fracture strength and fractured appearance of crowns according to different coping designs. A resin maxillary left central incisor analogue was prepared for a metal ceramic crown, and metal dies were made with duplication mold. Metal copings were made and assigned to one of four groups based on facial framework designs: group 1, coping with 0.5mm metal collar; group 2, metal extended to the shoulder; group 3, metal extended to 1mm coronal tn the shoulder: group 4, metal extended to 2mm coronal to the shoulder. Copings and crowns were adjusted to be same size and thickness, and cemented to metal dies with zinc phosphate cement by finger pressure. Fracture strength was measured with Instron Universal Testing Machine. Metal dies were anchored in Three-way-vice at 3mm below finish line and at $130^{\circ}$ inclined to the long axis of the crown. Load was directed lingually at 2mm below midincisal edge. Load value at initial crack and at catastrophic fracture was recorded. The results obtained were as follows : 1. Fracture strength values at initial crack were higher in groups 1, 2 than in groups 3, 4 but this difference was not statistically significant(P<0.05). 2. Conventional metal collared crown had greater catastrophic fracture strength than any other collarless crowns. 3. The greater the labial metal coping reduction, the lower the catastrophic fracture strength of crowns but when more than 1mm of labial metal reduction was done, the difference in strengths was not statistically significant(p<0.05). 4. The strongest collarless coping design was group 2.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.21 no.1
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• pp.27-34
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• 2015

Heating patterns depending on the packaging materials were examined in order to investigate the causes of thermal deformation of packages used for ready-to-eat foods for microwave heating due to the non-uniformity of microwaves. Physical properties including tensile strength, heat-resistance and elongation of four different CPP grades were compared. High retortable CPP had higher sealing strength and heat resistance compared to the conventional CPPs. All CPP samples tested were proved to have melting temperatures around $160^{\circ}C$. However, they were all thermally deformed by microwave heating due to a limited penetration of microwave and non-uniform heating within the spicy sauce of high viscosity contained high salt, especially on the above the filling line and sealing edge of pouches. When the laminated stand-up pouches composed of G-PET/PET/PET/CPP and G-PET/PET/NY/CPP were retorted and microwaved, significant deformations were noticed in both samples after retorting. Besides, pouches contained titanium dioxide showed more intense thermal deformation than the control. When the $10{\mu}m$ aluminium foil was affixed on the pouch, small thermal deformation was observed only in the bottom layer. More studies are required to prevent the thermal deformation of packaging materials used for RTE foods during microwave heating by developing the technologies to increase the thermal stability of CPP layer and the modification of packaging design to modify the microwave access into the package.

• The Journal of the Korea Contents Association
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• v.12 no.6
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• pp.182-190
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• 2012

Based on the study, the issues and trends in the current functional sandal designs on the same product line will be examined for the future developments for the functional sandals and the results were obtained as follows. First, the sandals must have a high front heel with wide floors that meet the ground. Second, the preference for the chromatic colour is stronger than the achromatic colors. Third, the sandals must be designed in curves in terms of the height and shape of the heels and design must consider the shoe's balance. Fourth, the product must appear big to provide a sense of stability. However, the sandals must not be designed too big to make them look crude or cause inconvenience while exercising. Fifth, the sandals must not be designed in too complex ways. This study has investigated and analyzed the external design of functional sandals and the user reviews on the actual sandals were not done. Through more detailed studies, the diversity in the design of functional sandals must be south and Korea's competitive edge in the industry and design must be secured for the future.