• Korean Journal of Remote Sensing
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• v.23 no.3
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• pp.199-209
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• 2007

Traditionally, aerial images have been used as main sources for compiling topographic maps. In recent years, lidar data has been exploited as another type of mapping data. Regarding their performances, aerial imagery has the ability to delineate object boundaries but omits much of these boundaries during feature extraction. Lidar provides direct information about heights of object surfaces but have limitations with respect to boundary localization. Considering the characteristics of the sensors, this paper proposes an approach to extracting buildings from lidar and aerial imagery, which is based on the complementary characteristics of optical and range sensors. For detecting building regions, relationships among elevation contours are represented into directional graphs and searched for the contours corresponding to external boundaries of buildings. For generating building models, a wing model is proposed to assemble roof surface patches into a complete building model. Then, building models are projected and checked with features in aerial images. Experimental results show that the proposed approach provides an efficient and accurate way to extract building models.

• Food Science and Preservation
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• v.22 no.2
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• pp.267-274
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• 2015

This study was conducted to evaluate the antioxidant activities and the quality characteristics of 70% ethanol extracts from onion peels with different extraction methods (autoclave extraction, AE; low temperature high pressure extraction, LTPE; reflux extraction, RE; and stirrer extraction, SE). The yields of AE, LTPE, RE and SE were 9.00%, 5.39%, 13.21% and 12.41%, respectively. The total polyphenol and flavonoid contents in the AE were significantly higher than in the other extracts. The DPPH radical scavenging abilities with a concentration of 100 mg% (w/v) were : AE, 28.9%; RE, 26.07%; LTPE, 24.35%; and SE, 19.53%. The ABTS radical scavenging ability and the nitrite scavenging activity showed the same tendency as that of the DPPH radical scavenging ability. The angiotensin-converting enzyme (ACE) inhibitory activities of the LTPE and AE were higher than those of the RE and SE. The ${\alpha}$-Glucosidase inhibitory activity of the RE was higher than that of the extracts with other extraction methods. The nitrite scavenging activities with a concentration of 10 mg/mL were: AE. 33.97%; RE, 35.47%; LTPE, 21.86%; and SE, 21.71%. The ferrous ion chelating activity of the LTPE (54.73%) was significantly higher than that of the other extracts. These results suggest that AE is the superior method for the enhancement of anti-oxidant activity, and onion peel can be used as a natural antioxidant material for health foods and can be a good ingredient of functional foods.

• Journal of Sericultural and Entomological Science
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• v.51 no.2
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• pp.180-184
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• 2013

Study on extraction and concentration of mulberry leaf were performed to increase utilization as new source of food additives. We analyzed extraction method in EtOH, sugar and hot water solution. The desirable method was 70% alcoholic extraction. Color of concentrate was comparatively stable in 70% alcoholic extraction solution and sugar solution. But hot water extraction was showed color change with brown. By filtering of concentrate in 70% alcoholic extraction and sugar extraction, we removed a deposits. Also, we investigated characteristics of the concentrate from mulberry leaf.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.6
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• pp.1403-1408
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• 2010

Korean information retrieval uses noun as index terms or keywords of representing the document. and noun and keyword extraction is to find all nouns presented in the document, In this paper, we proposes the method of keyword extraction using pre-built dictionary. This method reduces the execution time by reducing unnecessary operations. And noun, even large documents without affecting significantly the accuracy, can be extracted. This paper proposed noun extraction method using the appearance characteristics of the noun and keyword extraction method using unsupervised learning techniques.

• Journal of Korean Society on Water Environment
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• v.22 no.2
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• pp.288-293
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• 2006

Basic investigations have been carried out for the solvent extraction of silver contained in the waste photographic fixing solution using D2EHPA as an extractant. Extraction experiments were conducted using artificial waste solution which was made by dissolving $AgNO_3$ in distilled water along with actual waste fixing solution. For artificial waste solution, the extraction of silver was found to occur very rapidly at the initial stage of extraction. In addition, more silver was extracted as the volumetric ratio between aqueous phase and organic phase was decreased. The volumetric ratio of organic extractant to diluent was also taken as an influential variable and the extracted amount of silver was observed to decrease with temperature. The characteristics of silver extraction for actual fixing solution was generally similar to that for artificial waste solution. Regarding the kinetic analysis, the extraction of silver contained in the actual solution was observed to follow a first order reaction.

• Journal of Physiology & Pathology in Korean Medicine
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• v.23 no.6
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• pp.1416-1422
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• 2009

To observe the difference and change of the efficacy and ingredient appearing according to whether semen zizyphi spinosae has been roasted and its extraction method, locomotor activity, anticonvulsant activity, sleeping effect of each hot water and UMPM low temperature extracts of roast and raw semen zizyphi spinosae were measured through animal tests. Roast semen zizyphi spinosae showed superior pharmacological efficacy than raw semen zizyphi spinosae. Also, hot water extraction method showed superior pharmacological efficacy than low temperature extraction method(UMPM) that uses ultrasonic waves and microwaves. In short, it was shown that herbal medicine's extraction method needs to maximize medicinal effects by trying optimum extraction methods according to efficacy by considering characteristics of each herbal medicine. Together, there's also the need for in-depth studies on water-soluble ingredients of semen zizyphi spinosae that may be extracted through full hot water extraction method.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2010.05a
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• pp.165-166
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• 2010

Noun extraction is to find all nouns presented in the document, Korean information retrieval uses noun as index terms or keywords of representing the document. In this paper, we proposes the method of keyword extraction using pre-built dictionary. This method reduces the execution time by reducing unnecessary operations. And noun, even large documents without affecting significantly the accuracy, can be extracted. This paper proposed noun extraction method using the appearance characteristics of the noun and keyword extraction method using unsupervised learning techniques.

• Nuclear Engineering and Technology
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• v.23 no.4
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• pp.438-443
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• 1991

The operational characteristics of the duoplasmatron ion source are investigated in order to obtain the maximum achievable extraction current of the $He^+$ ion beam with the small divergence. Under the variations of the gas pressure, the arc current, the magnet current and the extraction voltage of the ion source, the change of the extracted $He^+$ ion beam current is observed. An oxide filament, the mixture of BaO and SrO coated on Ni meshes, is used as the hot cathode, and its average lifetime is about 100 hours. The extraction current is linearly proportional to the arc current. As the magnet current of the ion source is increased, the extraction current increases, but the beam divergence becomes larger. The maximum extraction current is obtained at the source pressure of 0.084 Torr. The extraction current is proportional to the extraction voltage raised to the power of 3/2 as estimated from theory. At the extraction voltage of 5.72 kV, the maximum extraction current of 50 $\mu$A is obtained under the optimized extraction condition.

• The Journal of Korea Robotics Society
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• v.7 no.3
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• pp.171-181
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• 2012

Outdoor mobile robots are faced with various terrain types having different characteristics. To run safely and carry out the mission, mobile robot should recognize terrain types, physical and geometric characteristics and so on. It is essential to control appropriate motion for each terrain characteristics. One way to determine the terrain types is to use non-contact sensor data such as vision and laser sensor. Another way is to use contact sensor data such as slope of body, vibration and current of motor that are reaction data from the ground to the tire. In this paper, we presented experimental results on terrain classification using contact sensor data. We made a mobile robot for collecting contact sensor data and collected data from four terrains we chose for experimental terrains. Through analysis of the collecting data, we suggested a new method of terrain feature extraction considering physical characteristics and confirmed that the proposed method can classify the four terrains that we chose for experimental terrains. We can also be confirmed that terrain feature extraction method using Fast Fourier Transform (FFT) typically used in previous studies and the proposed method have similar classification performance through back propagation learning algorithm. However, both methods differ in the amount of data including terrain feature information. So we defined an index determined by the amount of terrain feature information and classification error rate. And the index can evaluate classification efficiency. We compared the results of each method through the index. The comparison showed that our method is more efficient than the existing method.

• Nuclear Engineering and Technology
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• v.53 no.6
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• pp.1931-1938
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• 2021

Uranium ingot is produced by metallothermic reduction of uranium tetrafluoride using magnesium or calcium as reductant. Presence of oxygen containing compounds viz. uranyl fluoride and uranium oxide in the starting uranium fluoride has a significant effect on the firing time, final temperature of the charge, slag-metal separation and hence the metal recovery. As reported in the literature, the maximum tolerable limit for uranyl fluoride in the UF₄ is 2.5 wt% and limit for uranium oxide content is in the range 2-3 wt%. No theoretical or experimental basis is available till date for these limits. Analyses have been carried out in this study to understand the effect of UO₂F₂ concentration in the starting fluoride on the final temperature of the products and thus the reduction characteristics. UF₄ having uranyl fluoride concentration, less than as well as more than 2.5 wt%, have been investigated. Thermodynamic calculations have been carried out to arrive at a general expression for the final temperature attained by the products during calciothermic reduction of UF₄. Finally, an upper limit for the oxygen containing impurities has been estimated using the CaO-CaF₂ phase diagram.