• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.24 no.4
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• pp.459-465
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• 2013

This paper presents a differential interferometry technique for soil moisture change detection by measuring surface-height variation. COSMO-SkyMed SAR images were used to verify the DInSAR(differential interferometric SAR) technique. The soil penetration depth changes according to soil moisture, that causes phase change of the received signal. The height of soil surface and its displacement can be detected by a radar interferometry technique using phase difference of two received signals. To retrieve displacement variation, one of three SAR images is used as a reference image. Reference image and other two images are processed by the differential interferometry technique in the same area. The soil moisture was measured for the test sites to verify the DInSAR technique. The penetration depth is calculated by using the in-situ measured soil moisture data and it is compared with the displacement values acquired by the DInSAR technique.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.1
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• pp.142-147
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• 2020

This study investigates the effects of moisture content on diffuse ultrasound to be applied for the evaluation of micro-structural damage in concrete subjected to various environmental conditions. We monitored diffuse wave parameters for concrete samples in process of water saturation for 5 days. Dried samples were immersed in a water bath, and the change of moisture content in concrete were estimated by measuring the change of mass. For the diffuse wave analysis, a frequency range of 500 kHz, which represents a scattering regime of ultrasound in concrete, was selected. The test results reveal that the ultrasonic diffusivity slightly changed, and the ultrasonic dissipation significantly increased by approximately 120% in the process of water saturation. Therefore, the moisture content in concrete should be considered for the evaluation of micro-structural damage using diffuse wave techniques.

• Korean Journal of Remote Sensing
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• v.13 no.2
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• pp.151-163
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• 1997

In this paper, an algorithm for retrieving soil moisture from measurement of microwave reflection at the end of a coaxial canble is presented. Because the wave reflection from the boundary between air and soil layers depends on the dielectric constant of the soil layer, the dielectric constant can be obtained from measured reflection coefficient. At first, an equivalent circuit for the coaxial probe contaced on the soil surface was chosen with two unknown circuit elements. Then, the unknown circuit elements are obtained experrmentally by measuring the reflection constants of 20 soil samples, and consequently, an empirical formula for computing the dielectric constant from the reflection coefficient is obtained. The dielectric constant is mainly influenced by the soil moisture, and the soil moisture can be computed from the dielecfic constant using an existing empirical formula. HP Network Analyzer 8510C was used to measure the magnitude and the phase of the reflection coeffcient at 4.65 GHz, and the measured data set were used to obtain an empirical formula for computing the dielectric constant. The empirical formula obtained in this study was proven by other soil samples.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2011.03a
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• pp.54-54
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• 2011

방사 공정 최적화를 위해 칩(chip)건조를 실시하여 칩의 수분을 모두 제거한 후 실험을 진행하게 된다. 칩은 그 자체가 공정수분율(0.4%) 또는 그 이상의 수분을 함유하고 있으므로 건조하지 않고 방사하면 현저히 가수분해가 일어난다. 가수분해가 일어난다면 PET 분자량도 저하되어 고분자의 성질을 잃게 되어 방사된 섬유의 물리 화학적 성질에 중요한 영향을 받게 된다. 그러므로 가수분해를 방지하기 위하여 칩내 수분을 제거하는 건조 공정을 거치는 것이다. 개발된 나노은입자을 함유한 Ag/PET 마스터배치의 제사성 및 가연성 평가을 위한 파일럿연구를 행했다. 본 연구에서 사용한 은나노 M/B 칩(chip)의 경우 일반적으로 사용하는 PET 칩에 비하여 낮은 고유점도를 가지므로 방사성에 칩의 수분이 더욱 영향을 미칠 것이라 판단되어 건조공정에 특별한 주의을 하여 진행하였다. 마스터배치의 고유점도(IV)값의 변화에 따른 제사성 및 가연성 평가를 관찰하였다. #3 M/B 칩의 제사성이 #1 M/B 칩 대비 공정성이 개선되어 두 품종 모두 비출사가 발생하지 않았으며, M/B 제조시 분산제 유무에 따른 방사공정성의 차이는 없는 것으로 보인다. 따라서 #1 M/B 대비 공정성이 개선된 점은 M/B의 IV개선에 기인하는 것으로 판단되었다.

• The Journal of the Korea institute of electronic communication sciences
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• v.9 no.2
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• pp.173-180
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• 2014

The development process of a L-Band microwave radiometer for remote sensing of soil-moisture are described in this paper. Achieving the development aim of the measurement accuracy within 2% for soil moisture content of 0~50%, the requirements and specifications of the microwave radiometer and its receiver are drawn. The receiver with high gain, high sensitivity is designed and implemented to satisfy these requirements and specifications. The receiver has the bandwidth of 40 MHz, the system gain of 50 dB and the sensitivity of average value 0.19 K, maximum value 0.313K at 1390 MHz.

• KSBB Journal
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• v.20 no.5 s.94
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• pp.383-386
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• 2005

Grape seed oil made by press or organic solvent extraction does not contain resveratrol, a bioactive compound. Supercritical carbon dioxide could extract oil containing resveratrol from grape seed. The extraction efficiency was mainly dependent on the water content in grape seed. More resveratrol was contained in the oil extracted with un-dried grape seed. No resveratrol was extracted with dried grape seed. Time course changes of grape seed oil extraction also resulted that resveratrol could be extracted by supercritical carbon dioxide with the positive influence of water.

• Korean Journal of Environmental Biology
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• v.26 no.4
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• pp.271-278
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• 2008

The differences of several kinds of physiological responses between Commelina communis (C$_3$ plant) and Sedum sarmentosum (CAM plant: Crassulacean Acid metabolism) when both plants were exposed to water stress for 3 weeks were investigated. In case of Commelina it was shown a clear loss of water to 12% in three weeks, but no changes were observed in Sedum. Total chlorophyll content was also reduced to 57% in Commelina but not clear changes of chlorophyll content in Sedum. were observed for three weeks. In chlorophyll fluorescence experiments Fv/Fm ratios were reduced to 19% in Commelina, but no changes were observed in Sedum. There were very sensitive responses according to the different KCl concentrations and the stomatal aperture of epidermal strips was 12.8 ${\mu}m$ at 200 mM KCl in Commelina, but less than 3 ${\mu}m$ was observed at the same KCl concentration in Sedum. In addition, there were no chloroplasts in guard cells of Sedum, but most plants had chloroplasts including Commelina. From the above results, the ability of water stress resistance in Sedum. could be come from slow physiological metabolism including growth and less loss of water through unique stomatal characteristics.

• The Korean Journal of Food And Nutrition
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• v.17 no.3
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• pp.313-321
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• 2004

Separation-concentration of sulfur containing heterocyclic compounds(SCHC) from many reaction meat flavors manufactured with Maillard reaction was carried out. Profile of SCHC was identified and analyzed by GC and GC-MSD. The results were as follows. 1. Profile of SCHC could be identified 7 kinds thiazole and 11 kinds thiophene, the major produced compounds were thiophene, thiazolidine, 4-methyl-5-thiazole ethanol. 2. In the case of SCHC, relationship between changes of reaction conditions and the kind of produced components were as same, but produced amounts appeared the difference. Producing amount of complexed SCHC and caramellike note as well as oxygen containing heterocyclic compounds were high level more than high reaction temperature and long time reaction period. 3. Producing ratio of comparative simple structural SCHC were the highest level at reaction conditions of moisture content 50%, reaction temperature 100$^{\circ}C$ and reaction time 2 hours. Reaction conditions for the revelation of reaction meat flavor were below 110$^{\circ}C$ and less than 2 hours. 4. Relationship between moisture content and reaction temperature as well as reaction time had very relative relation. From the change of moisture content and reaction conditions could be obtained the simultaneously profile. Signal presentation for production of reaction meat flavor could be from extraction-separation-concentration of SCHC through simplification of raw-materials in the flavor and seasoning food industry.

• Polymer(Korea)
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• v.27 no.2
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• pp.113-119
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• 2003

The thermal properties and crystallization behaviors of poly(ethylene terephthalate) (PET) were investigated by controlling the annealing conditions of PET sample, such as relative humidity, temperature, and time. The variations of moisture content, glass transition temperature ($T_g$) and cold crystallization temperature ($T_{\propto}$) were examined after annealing the PET sample. Subsequently crystallization process was performed with the annealed PET specimen, and then the degree of crystallinity and heat distortion temperature (HDT) of variously crystallized PET specimen were examined. Residual stress relaxation in the injection molded PET sample after annealing was also observed through polarized films. Moisture content in the PET specimen increased up to 6000 ppm with increasing the relative humidity, temperature, and time of annealing. $T_g$ and $T_{\propto}$ of the annealed PET specimen decreased with increasing moisture content. The degree of crystallinity increased as increasing moisture content in the PET specimen. However for same moisture content, the degree of crystallinity varied with annealing conditions. The relaxations of residual stress in the PET sample differed from annealing conditions, and the maximum degree of crystallinity increased with decreasing residual stress in the PET sample.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2018.04a
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• pp.73-73
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• 2018

최근 매실나무를 기주로 한 겨우살이의 인공재배에 성공함에 따라, 식품 소재로 이용하기 위해 일반성분을 분석하였다. 경기도 남양주시에서 매실나무를 기주로 한 인공재배 겨우살이를 채취하여 동결건조한 후 수분, 조단백질, 조지방, 회분, 탄수화물, 베타카로틴, 비타민 B1, 비타민 B2, 비타민 B3, 비타민C, Ca, Fe, K, Na 그리고 P의 함량을 분석하였다. 조단백질, 조지방, 회분, 베타카로틴, Ca, Fe, K, Na 그리고 P은 AOAC 방법을 이용하여 분석하였고, 탄수화물은 탄수화물(%) = 100 - (조단백질% + 조지방% + 회분% + 수분%) 계산식을 활용하여 산출하였다. 수분, 비타민 B1, 비타민 B2, 비타민 B3, 비타민 C는 식품공전에 제시된 방법에 따라 분석하였다. 동결건조한 매실나무겨우살이의 일반성분은 탄수화물 58.90%, 단백질 22.36%, 회분 11.11%, 지방 5.37%, 수분 2.26% 순으로 함유하였다. 비타민의 함량은 비타민 C 4.78mg/100g, 나이아신 1.87mg/100g, 비타민 A 1.42mg/100g, 비타민 B2 0.73mg/100g 그리고 비타민 B1 0.30 mg/100g의 순서로 많이 함유하였다. 무기질은 K 3141.54mg/100g, Ca 977.77mg/100g, P 309.91 mg/100g, Na 20.13mg/100g 그리고 Fe 8,24mg/100g의 순서로 많이 함유하였다.