• Geophysics and Geophysical Exploration
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• v.10 no.1
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• pp.50-59
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• 2007

The advent of towed geo-electrical array surveying on water and land has resulted in datasets of magnitude approaching that of airborne electromagnetic surveying and most suited to 1D inversion. Robustness and complete automation is essential if processing and reliable interpretation of such data is to be viable. Sharp boundaries such as river beds and the top of saline aquifers must be resolved so use of smoothness constraints must be minimised. Suitable inversion algorithms must intelligently handle low signal-to-noise ratio data if conductive basement, that attenuates signal, is not to be misrepresented. A noise-level aware inversion algorithm that operates with one elastic thickness layer per electrode configuration has been coded. The noise-level aware inversion identifies if conductive basement has attenuated signal levels so that they are below noise level, and models conductive basement where appropriate. Layers in the initial models are distributed to span the effective depths of each of the geo-electric array quadrupoles. The algorithm works optimally on data collected using geo-electric arrays with an approximately exponential distribution of quadrupole effective depths. Inversion of data from arrays with linear electrodes, used to reduce contact resistance, and capacitive-line antennae is plausible. This paper demonstrates the effectiveness of the algorithm using theoretical examples and an example from a salt interception scheme on the Murray River, Australia.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.17 no.8 s.111
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• pp.773-787
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• 2006

An airborne radar is an essential aviation electronic system for the aircraft to perform various civil and/or military missions in all weather environments. This paper presents the design, development, and test results of the multi-mode X-band pulsed Doppler radar system test model for helicopter-borne flight test. This radar system consists of 4 LRUs(Line-Replacement Unit), which include antenna unit, transmitter and receiver unit, radar signal & data processing unit and display Unit. The developed core technologies include the planar array antenna, TWTA transmitter, coherent I/Q detector, digital pulse compression, MTI, DSP based Doppler FFT filter, adaptive CFAR, moving clutter compensation, platform motion stabilizer, and tracking capability. The design performance of the developed radar system is verified through various ground fixed and moving vehicle test as well as helicopter-borne field tests including MTD(Moving Target Detector) capability for the Doppler compensation due to the moving platform motion.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2000.04a
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• pp.6-7
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• 2000

개발도상국의 급격한 인구 증가에 의해 세계 60억 이라는 인구도 2050년을 맞아 약 100억에 도달할 것이라고 일컬어진다. 이로 인한 장래의 식량 위기에 대비하여 벼, 밀, 옥수수 등의 증산, 품종 개발도 물론 필요하지만 선진국을 중심으로 시장성 높은 작물의 소비가 우선되어지는 상황에 맞추어 세계적으로 주식이 될 수 있는 새로운 곡류의 확보와 생산체제도 중요한 문제이다. 한편으로 생활의 향상에 따른 식물의 다양화와 건강지향의 관점으로 본 다 품목 소량형의 식생활을 하는 것이 식물성 allergy의 방지 측면으로서의 곡류 특히 잡곡류의 유효 이용이 부각되어진다. 이들 중 amarans, quinoa는 벼과 식물에 비교해서 광합성능이 좋은 C4식물로서 생장이 빠르고 동시에 비타민, 무기질, 지질이 풍부하고 구성 단백질 중에 필수 아미노산을 많이 함유하여 아미노산 등급도 높고 특히 영양 발란스도 우수하다. 또 cholesterol 저하작용, 식물섬유에 의한 대장암의 억제 작용 등이 잘 알려져 있다. 그리l고 quinoa에 대해서는 아메리카 항공우주국(NASA)에서 CELSS(Controlled Ecological Life Support System; 장기간 우주특무비행의 승선원을 위한 공기중의 이산화탄소를 제거하고 식량·산소·물을 만들어 내기 위해 식물을 이용하는 방법)에 적합한 작물 후보로써 선택되어 신규 식품소재로써 주목받고 있다. 이상과 같은 견지로부터 amarans, quinoa를 일상식화되고 있는 빵에 이용하기 위해 제빵성 및 혼합중의 반죽의 모든 성질에 대해서 검토했다. amarans는 초과의 Amaranthus에 속하고 주요 생산국은 아메리카, 멕시코, 페루등이지만 일본에서는 주로 A.hypochondriacus가 수입되어 이용 되어지고 있다.amarans의 가루는 단독으로는 점탄성 있는 반죽을 형성하지 않기 때문에 밀가루에 일부를 대용한 wheat flour dough를 사용하고 가정용 제빵기로 구워 최종 단계에까지의 제빵성 결과를 산출했다. amarans folur 5%의 대체에는 빵의 비용적이 비교적 증대했지만 그 이상 amarans flour을 대처하면 확연히 비용적은 감소했다. amarans flour 10% 대체에 hemicellulase 1250U 이상을 첨가하면 비용적은 눈에 띄게 증대했다. farinograph에 있어서 반죽의 안정성은 amarans flour 10% 대용에 현저히 감소했다. 반죽의 점탄성(아축응력, 탄성률, 점성계수)는 amarans flour 10%를 대용한 것이 무첨가한 것보다 많이 단단해졌음을 알 수 있었다. 혼합중의 반죽의 조사형 전자현미경 관찰로 amarans flour로 대체한 gluten이 단단해졌음을 알수 있었다. 유화제 stearly 칼슘, 혹은 hemicellulase를 amarans 10% 대체한 밀가루에 첨가하면 확연히 비용적을 증대시킬 수 있다는 사실을 알 수 있었다. quinoa는 명아주과 Chenopodium에 속하고 페루, 볼리비아 등의 고산지에서 재배 되어지는 것을 시료로 사용하였다. quinoa 분말은 중량의 5-20%을 quinoa를 대체하고 더욱이 분말중량에 대하여 0-200ppm의 lipase를 lipid(밀가루의 2-3배)에 대하여 품질개량제로서 이용했다. 그 결과 quinoa 대량 7.5%에서 비용적, gas cell이 가장 긍정적 결과를 산출했고 반죽의 조직구조가 강화되었다. 또 quinoa 대체에 의해 전분-지질 복합제의 흡열량이 증대된 것으로부터 전분-지질복합제의 형성 촉진이 시사되었다.이것으로 인하여 호화억제에 의한 노화 방지효과가 기대되었지만 실제로 빵의 노화는 현저히 진행되었다. 이것은 quinua 대체량 증가에 따른 반죽의 안정성이 저하되어 버린 것으로 생각되어진다. 더욱이 lipase를 첨가하면 반죽이 분화하는 경향이 보여졌지만 첨가량 75ppm에 있어서 상당히 비용적의 증대가 보였다. 이것은 lipase의 가수분해에 의해 생긴 monogliceride에 의한 유화각 일어나서 보존성이 개선되어진 것으로 quinoa를 보다 많이 빨에 이용하기 위해서는 lipaserk 품질개량제로서 유효하다는 것을 알 수 있었다. 또 lipase는 quinoa의 대체량이 비교적 많은 10-20%의 섭취가 곧 allergy 질환 문제의 개선책이 되는 것은 물론 amarans, quinoa에는 lysine, 함황아미노산이 많고 지질중의 지방산조성도 좋고 무기질도 많이 함유되어 있다. 이와같이 우리들 개인의 건강에 대한 배려도 있고 amarans, quinoa등의 식품재료를 적극적으로 사용할 수 있도록 유념해 두었으면 하는 바램이다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.6
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• pp.1775-1781
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• 2008

The effects of the type of curing agent on the swelling of the natural rubber(NR) sponge applicable to the self-sealing layer of a helicopter fuel tank were investigated. The curing systems employed were peroxide and mixed ones of sulfur and peroxide. The NR compounds were prepared in a kneader and a roll-mill. The compounds were partially cured in a press at high pressure and subsequently cured fully with expansion in another press at atmospheric pressure. The apparent density of the NR sponge was measured and the cell structure was observed with scanning electron microscopy. The swelling experiments were performed at room temperature using toluene, iso-octane, and an aircraft fuel as a solvent. More rapid volume swelling of the NR sponge cured by peroxide was achieved than cured by sulfur and peroxide with similar amount of curing agent added in rubber compounds. The apparent density and cell structure of the sponge were extremely sensitive to the amount of peroxide, which influences again the swelling behavior of the NR sponge. It is important to control properly two reactions of decomposition of foaming agent and crosslinking of NR in the mold to obtain rapid swelling of the NR sponge on contact of the fuel.

• Archives of design research
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• v.17 no.1
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• pp.383-392
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• 2004

The power tools is the product using working power generated by electric motor. Many companies are manufacturing numerous devices. Main features of tools are included various assembled products, small, light and solid and durable enough to match several standards. Fundamental requirements for the product is excellent performance and convenience for use. The quality of them depends on the equipped motor'(s) capability, accuracy of gear and endurance against worn-out. By adapting the state-of-the-art parts, they could be used in the place from home to heavy industry broadly. They can be classified electronic drills, grinders, saws and sanders families for the household appliances. For industrial tools, bore drill, grinder, polisher, and driver drill are classified as special and high priced group. This study presents the strategy of power tool development of BOSCH, BLACK&DECKER and KEYANG. Their products were analyzed in terms of product line and product mix concept. Then they are examined by design elements, such as color, shape and material for housing. As an analysis method, the image scale parameter and criteria were applied to each company's product.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2006.05a
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• pp.489-492
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• 2006

Red tide occurred sporadically in early 90s. But It is happening extensively by global warming. So, Airline observation, Red tide buoy development, and Red tide alarm system research is progressing for monitor ring. However, study to early forecast red tide and red tide alarm system did not exist hard. This paper proposed development that design and implementation red tide database of using wireless sensor network. There are GPS, Water Temperature sensor, Oxygen sensor, and Turbidity sensor in each node. And data is stored to red tide database through Ad-hoc network. This data is integrated and analyzed. So, forecast red tide. And red tide database has red tide data that happen at past. This is utilized to comparative analysis data for red tide estimate. Main screen displays position of node and measured value in electron map. Much studies must be backed for this a study. But I think that contribute to analyze red tide data by red tide database construction.

• Korean Journal of Remote Sensing
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• v.15 no.2
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• pp.91-105
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• 1999

Spatial data integration using multiple geo-based data sets has been regarded as one of the primary GIS application issues. As for this issue, several integration schemes have been developed as the perspectives of mathematical geology or geo-mathematics. However, research-based approaches for statistical/quantitative assessments between integrated layer and input layers are not fully considered yet. Related to this niche point, in this study, spatial data integration using multiple geoscientific data sets by known integration algorithms was primarily performed. For spatial integration by using raster-based GIS functionality, geological, geochemical, geophysical data sets, DEM-driven data sets and remotely sensed imagery data sets from the Ogdong area were utilized for geological thematic mapping related by mineral potential mapping. In addition, statistical/quantitative information extraction with respective to relationships among used data sets and/or between each data set and integrated layer was carried out, with the scope of multiple data fusion and schematic statistical assessment methodology. As for the spatial integration scheme, certainty factor (CF) estimation and principal component analysis (PCA) were applied. However, this study was not aimed at direct comparison of both methodologies; whereas, for the statistical/quantitative assessment between integrated layer and input layers, some statistical methodologies based on contingency table were focused. Especially, for the bias reduction, jackknife technique was also applied in PCA-based spatial integration. Through the statistic analyses with respect to the integration information in this case study, new information for relationships of integrated layer and input layers was extracted. In addition, influence effects of input data sets with respect to integrated layer were assessed. This kind of approach provides a decision-making information in the viewpoint of GIS and is also exploratory data analysis in conjunction with GIS and geoscientific application, especially handing spatial integration or data fusion with complex variable data sets.

• Korean Journal of Optics and Photonics
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• v.33 no.4
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• pp.146-158
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• 2022

The detector of a focal-plane-array mid-wave infrared (MWIR) camera has different response characteristics for each detector pixel, resulting in nonuniformity between detector pixels. In addition, image nonuniformity occurs due to heat generation inside the camera during operation. To solve this problem, in the process of camera manufacturing it is common to use a gain-and-offset table generated from a blackbody to correct the difference between detector pixels. One method of correcting nonuniformity due to internal heat generation during the operation of the camera generates a new offset value based on input frame images. This paper proposes a technique for dividing an input image into block image patches and generating offset values using only homogeneous patches, to correct the nonuniformity that occurs during camera operation. The proposed technique may not only generate a nonuniformity-correction offset that can prevent motion marks due to camera-gaze movement of the acquired image, but may also improve nonuniformity-correction performance with a small number of input images. Experimental results show that distortion such as flow marks does not occur, and good correction performance can be confirmed even with half the number of input images or fewer, compared to the traditional method.

• Journal of International Area Studies (JIAS)
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• v.18 no.3
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• pp.145-168
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• 2014

Given the distance from Mt. Baekdu, volcanic ash will have the direct impact on South Korea in case Mt. Baekdu erupts. Ash fall deposits or particulate matters(PM10) in the air will cause damages in various sectors. In particular, the PM10 impact on the manufacturing sector when the ash disperses in Korea is needed to be assessed since South Korea's manufacturing sector accounts for more than 30% of GDP. Meanwhile the economic impacts of PM10, including Asian dust, have been researched in Korea as the events become frequent, and losses in the manufacturing have been also reported. This study is to identify vulnerable sectors to volcanic ash in the korean industry, and to assess economic losses in case of a Mt. Baekdu eruption scenario, based on the historical loss experience with particulate matters. Study results show that airline, precision such as electronics and semiconductors, distribution, shipbuilding, car, leisure, glass, dairy farming are vulnerable to volcanic ash, or PM10. The economic losses in both car and shipbuilding industry is estimated to 46.49 billion Korean won due to shutdown for 6 hours in case of a Mt. Baekdu eruption scenario.

• Korean Journal of Remote Sensing
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• v.39 no.6_2
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• pp.1541-1551
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• 2023

Radiometric calibration is a fundamental step in ocean color remote sensing since the step to derive solar radiance spectrum in visible to near-infrared wavelengths from the sensor-observed electromagnetic signals. Generally, satellite sensor suffers from degradation over the mission period, which results in biases/uncertainties in radiometric calibration and the final ocean products such as water-leaving radiance, chlorophyll-a concentration, and colored dissolved organic matter. Therefore, the importance of radiometric calibration for the continuity of ocean color satellites has been emphasized internationally. This study introduces an approach to improve the radiometric calibration algorithm for the visible bands of the Geostationary Ocean Color Imager-II (GOCI-II) satellite with a focus on stability. Solar Diffuser (SD) measurements were employed as an on-orbit radiometric calibration reference, to obtain the continuous monitoring of absolute gain values. Time series analysis of GOCI-II absolute gains revealed seasonal variations depending on the azimuth angle, as well as long-term trends by possible sensor degradation effects. To resolve the complexities in gain variability, an azimuth angle correction model was developed to eliminate seasonal periodicity, and a sensor degradation correction model was applied to estimate nonlinear trends in the absolute gain parameters. The results demonstrate the effects of the azimuth angle correction and sensor degradation correction model on the spectrum of Top of Atmosphere (TOA) radiance, confirming the capability for improving the long-term stability of GOCI-II data.