• Transactions on Electrical and Electronic Materials
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• 제18권5호
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• pp.273-278
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• 2017

Recently, one of the areas where research is being actively conducted is the Internet of Things (IoT). The field of using the Internet of Things system is increasing, coupled with a remarkable increase of the use of the camera. However, general cameras used in the Internet of Things have limited viewing angles as compared to those available to the human eye. Also, cameras restrict observation of objects and the performance of observation. Therefore, in this paper, we propose a panoramic image stitching method using feature extraction and matching based on an embedded system. After extracting the feature of the image, the speed of image stitching is improved by reducing the amount of computation using the necessary information so that it can be used in the embedded system. Experimental results show that it is possible to improve the speed of feature matching and panoramic image stitching while generating a smooth image.

• 천문학회보
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• 제36권2호
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• pp.127.1-127.1
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• 2011

Over the past several years the millimeter wave VLBI(Veryl Long Baseline Interferometry) observations have been intensively carried out. However In millimeter and sub-millimeter waves observations for VLBI, it is crucial to calibrate correctly the phase variations of the electromagnetic waves propagation through the troposphere. To do this, KVN(Korean VLBI Network) has a unique multi-frequency bands receiver system which is able to perform the simultaneous observations in up to four bands such as 22, 43, 86, and 129GHz. The phase of a source at 22GHz can be used to calibrate the phase of the same source at higher frequency bands. The phase calibration using multi-frequency bands receiver system is possible because the phase fluctuations from a given amount of waver vapor increase linearly with frequency. That is to say that troposphere is non-dispersive property in terms of tropospheric delay fluctuations. In this talk, We present results of test observation for multi-frequency bands receiver system.

• 국제학술발표논문집
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• The 1th International Conference on Construction Engineering and Project Management
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• pp.1042-1047
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• 2005

A web-based camera (webcam) is expected to enhance construction operation monitoring. However, webcams are often installed outside a building because their mobility is limited by cable wiring, which makes it difficult to monitor construction operations inside the building. If a webcam is integrated with emerging wireless communication technologies, construction professionals may be able to monitor interior construction operations using webcams without getting network cables wired on a congested and dynamic construction job site. However, one may concern that wireless communication may not be fast enough to transport all webcam images seamlessly. This paper presents an investigation as to the observation error of webcam images when a limited amount of images are delivered.

• 한국세라믹학회지
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• 제27권1호
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• pp.55-61
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• 1990

Effect of Al2O3 addition on the mechanical properties and microstructure of Ce-TZP were studied. 12, 14, 16Ce-TZP containing 0-40wt% Al2O3 were prepared by sintering at 155$0^{\circ}C$ for 2h. in air. Density, linear shrinkage, bending strength, Vickers hardness, microstructuer and the amount of stress induced phase transformation were examined. Vickers hardness increased linearly with increasing amounts of Al2O3. The amount of transformation and fracture toughness decreased linearly with increasing amount of Al2O3. Linear shrinkage and relative density decreased with increasing Al2O3 content in all composition of Ce-TZP. Grain growth of Ce-TZP was inhibited by Al2O3 dispersion and fracture mode of Ce-TZP/Al2O3 composites transformed from intergranular to transgranular fracture as the amount of Al2O3 increased. TEM observation revealed that Al2O3 particles were located mainly at grain boundaries of ZrO2.

• 한국제4기학회지
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• 제14권2호
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• pp.117-123
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• 2000

본 연구에서는 속초 지방의 강수 분포 특성을 파악하고자, 1970~1999년의 속초 기상대의 시간별.일별.월별 강수자료와 속초공항, 간성, 설악산관리사무소, 오색, 진부령, 미시령의 월별 강수자료를 분석하였다. 이 결과를 요약하면 다음과 같다. 속초 지방의 30년간(1970~1999) 강수량의 경년 변화를 보면 연강수량이 증가하는 추세에 있다. 봄(4, 5, 6월), 여름(6, 7, 8월), 가을(9, 10, 11월)에 7개 관측지점 중 고도 148m인 설악산 관리 사무소에서 강수량이 가장 많았는데, 이는 습윤한 해풍이 설악산관리사무소가 있는 쌍천 계곡으로 불어들기 때문이다. 여름철에는 7개 관측지점 중 고도가 가장 높은 미시령이 고도가 가장 낮은 속초 공항보다 95.2mm의 강수량이 많았는데, 겨울철에는 속초 공항이 미시령보다 89.6mm의 강수량이 많았다. 속초 지방에서 호우가 나타난 1984년 9월 2일(314.2mm)의 주 풍향은 북북동풍이었고, 일평균 풍속은 4.4㎧였다. 대설이 나타난 1978년 12월 19일(74.2cm)의 주풍향은 북서풍이었고, 일 평균풍속은 3.6㎧였다. 호우와 대설이 나타난 날은 지상과 상층에서 강한 북동기류가 동해안(속초 지방)으로 유입되었다.

• PNF and Movement
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• 제18권1호
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• pp.23-34
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• 2020

Purpose: To explore the effects of action observation combined with modified constraint-induced movement therapy on upper-extremity function and the activities of daily living in subacute stroke patients. Methods: Twenty-four subacute stroke patients were randomly assigned to the experimental group or the control group (n = 12 each). Both groups received therapy based on motor learning concepts, including repetitive and task-specific practice. The experimental group watched video clips for 10 minutes related to tasks performed during modified constraint-induced movement therapy while the control group watched videos unrelated to upper-extremity movement. These programs were performed for 40 minutes a day five times a week for four weeks. Their scores on the Fugl-Meyer assessment of upper extremities (FMA-UE), the action research arm test (ARAT), a motor activity log (amount of use [AOU] and quality of movement [QOM]), and the modified Barthel index (MBI) were recorded. Results: In both groups, all variables were significantly different between the pre-test and post-test periods (p < 0.05). The post-test variables were significantly different within each group (p < 0.05). In the experimental group, the changes between pre-test and post-test scores in the FMA-UE (14.39 ± 4.31 versus 6.31 ± 4.63), the ARAT (16.00 ± 4.73 versus 11.46 ± 3.73), MAL-AOU (1.57 ± 0.15 versus 1.18 ± 0.28), and MBI (27.54 ± 4.65 versus 18.08 ± 8.52) were significantly higher than those of the control group (p < 0.05). Conclusion: These findings suggest that action observation combined with modified constraint-induced movement therapy may be a beneficial rehabilitation option to improve upper-extremity function in subacute stroke patients with moderate impairment.

• Journal of Astronomy and Space Sciences
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• 제40권1호
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• pp.35-44
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• 2023

Surveillance and reconnaissance intelligence in the space domain will become increasingly important in future battlefield environments. Moreover, to assimilate the military provocations and trends of hostile countries, imagery intelligence of the highest possible resolution is required. There are many methods for improving the resolution of optical satellites when observing the ground, such as designing satellite optical systems with a larger diameter and lowering the operating altitude. In this paper, we propose a method for improving ground observation resolution by using an optical system for a previously designed low orbit satellite and lowering the operating altitude of the satellite. When the altitude of a satellite is reduced in a circular orbit, a large amount of thrust fuel is required to maintain altitude because the satellite's altitude can decrease rapidly due to atmospheric drag. However, by using the critical inclination, which can fix the position of the perigee in an elliptical orbit to the observation area, the operating altitude of the satellite can be reduced using less fuel compared to a circular orbit. This method makes it possible to obtain a similar observational resolution of a medium-sized satellite with the same weight and volume as a small satellite. In addition, this method has the advantage of reducing development and launch costs to that of a small-sized satellite. As a result, we designed an elliptical orbit. The perigee of the orbit is 300 km, the apogee is 8,366.52 km, and the critical inclination is 116.56°. This orbit remains at its lowest altitude to the Korean peninsula constantly with much less orbit maintenance fuel compared to the 300 km circular orbit.

• 대기
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• 제23권2호
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• pp.171-186
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• 2013

Recently, the number of observations used in a data assimilation system is increasing due to the enormous amount of observations, including satellite data. However, it is not clear that all of these observations are always beneficial to the performance of the numerical weather prediction (NWP). Therefore, it is important to evaluate the effect of observations on these forecasts so that the observations can be used more usefully in NWP process. In this study, the adjoint-based Forecast Sensitivity to Observation (FSO) method with the KMA Unified Model (UM) is applied to two high-impact weather events which occurred in summer and winter in Korea in an effort to investigate the effects of observations on the forecasts of these events. The total dry energy norm is used as a response function to calculate the adjoint sensitivity. For the summer case, TEMP observations have the greatest total impact while BOGUS shows the greatest impact per observation for all of the 24-, 36-, and 48-hour forecasts. For the winter case, aircraft, ATOVS, and ESA have the greatest total impact for the 24-, 36-, and 48-hour forecasts respectively, while ESA has the greatest impact per observation. Most of the observation effects are horizontally located upwind or in the vicinity of the Korean peninsula. The fraction of beneficial observations is less than 50%, which is less than the results in previous studies. As an additional experiment, the total moist energy norm is used as a response function to measure the sensitivity of 24-hour forecast error to observations. The characteristics of the observation impact with the moist energy response function are generally similar to those with the dry energy response function. However, the ATOVS observations were found to be sensitive to the response function, showing a positive (a negative) effect on the forecast when using the dry (moist) norm for the summer case. For the winter case, the dry and moist energy norm experiments show very similar results because the adjoint of KMA UM does not calculate the specific humidity of ice properly such that the dry and moist energy norms are very similar except for the humidity in air that is very low in winter.

• 한국세라믹학회지
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• 제12권2호
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• pp.21-25
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• 1975

As the major alumina source, domestic alunite was applied to synthesize the clinker for rapid hardening cement. The main minerals of the clinker were found to be C3S, C11A7-CaF2 and some C4AF by means of chemical treatment, x-ray diffraction analysis and microscopic observation. Rapid hardening cement was made of the clinker by adding suitable amount of hemi-hydrite and anhydrite. The setting time of the cement was regulated with citric acid as setter.

• Communications for Statistical Applications and Methods
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• 제10권2호
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• pp.423-432
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• 2003

The data observed at different positions are called the estimate of interested variable at new observation point on the Kriging utilize the space estimate technique, in which case there is correlation spatially. In this paper we provide the estimate for Variogram and Kriging methods as a field of kriging theory and dealt with actually measured data. And at the same time we forecast the amount of ozone that was not measured at this point by Kriging method and compared Ordinary Kriging method with Inverse Distance Kriging method.