• Archives of Pharmacal Research
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• 제28권4호
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• pp.458-462
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• 2005

The water content of skin was determined using a FT near infrared (NIR) spectrometer. NIR diffuse reflectance spectra were collected from hairless mouse, in vitro, and from human inner arm, in vivo. It was found that the variation of NIR absorbance band 1450 nm from OH vibration of water and 1940 nm from the combination involving OH stretching and OH deformation, depending on the absolute water content of separated hairless mouse skin, in vitro, using the FT NIR spectrometer. Partial least squares regression (PLSR) was applied to develop a calibration model. The PLS model showed good correlation. For practical use of the evaluation of human skin moisture, the PLS model for human skin moisture was developed in vivo on the basis of the relative water content of stratum corneum from the conventional capacitance method. The PLS model predicted human skin moisture with a standard errors of prediction (SEP) of 3.98 at 1130-1830 nm range. These studies showed the possibility of a rapid and nondestructive skin moisture measurement using FT NIR spectrometer.

• Agricultural and Biosystems Engineering
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• 제2권2호
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• pp.63-68
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• 2001

The objective of this study was to develop a real-time soil moisture meter using RF impedance. The impedance suchas capacitance and resistance (or conductance) was analyzed using parallel cylinder type capacitance probe(C-probe) and Q-meter (HP4342). The capacitance and conductance of soil increased as volumetric water content increased. The 5 MHz of modified Colpitts type crystal oscillator was designed to detect the capacitance change of the C-probe with moist soil. A third order polynomial regression model was proposed to describe the relationship between RF impedance and volumetric water content. The prototype real time moisture meter consisted of the C-probe, sample container, oscillator, frequency counter and related signal processing units. The calibration equation for measurement of volumetric moisture content of soil was developed and validated. The correlation coefficient and root mean square error between measured volumetric water content by oven method and predicted values by prototype moisture meter for unknown soil samples were 0.984 and 0.032$cm^3$$cm\^3$, respectively.

• 한국연소학회지
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• 제14권3호
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• pp.16-23
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• 2009

It is strongly desired for coal-fired power plants to utilize not only low-rank coals with high moisture contents, but also lowering cost with diversifying fuel sources. In this study, combustion characteristics of low rank coal with high moisture, and standard pulverized coals are experimentally investigated using TGA (Thermogravimetric Analysis) and DTF (drop tube furnace). The coals tested are three kinds of coal with moisture content ranging from 8.32 to 26.82%. The results show that under the air combustion condition, the burn-out time at TGA rises as moisture content increases, and standard pulverized coal with 8.32% moisture content showed the lowest activation energy of 55.73 kJ/mol. In case of the high amount of moisture, the combustion efficiency decreases due to evaporation heat loss, and unburned carbon in ash produced at combustion process in DTF increased. Aslo, initial deformation temperature of slag attached in alumina tube of DTF decreased with lowering the crytallinity of anorthite and augite. To improve the combustion reactivity and efficiency, it is effective to upgrade through drying the high moisture coal to moisture level (less than 10%) of standard pulverized coal.

• Journal of Biosystems Engineering
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• 제15권2호
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• pp.99-109
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• 1990

Rough rice is subjected to a series of static and dynamic forces during mechanical harvesting, handling and processing operations. The mechanical properties such as bioyield point, compressive strength, and deformations at the bioyield point and rupture point are important engineering data needed to develop processing machines and to determine reasonable operating conditions for these machines. The objectives of this study were to determine the mechanical properties of the rough rice kernel at loading rate of 0.664 mm/min and 1.673 mm/min and at various moisture contents, and to examine the effect of the moisture content and the loading rate on these mechanical properties. The follwing results were obtained from the study. 1. Bioyield point, rupture point, bioyield strength and ultimate strength of the rough rice kernel generally decreased in magnitude with an increase in moisture content. A little larger values of these mechanical properties were obtained at the higher loading rate. The rough rice variety and the loading rate affected significantly these mechanical properties at low moisture content, but not at the higher moisture levels. 2. Bioyield point of the sample grains varied from 20 to 80 N, and rupture point varied from 45 to 130N. Bioyield point for Japonica-type rough rice was a little higher than that for Indica-type rough rice, but there were little differnces in rupture point between two types of rough rice. 3. Bioyield strength and ultimate strength of the Japonica-type rough rice varied from 10 MPa. to 39 MPa., and from 13 MPa. to 45 MPa. respectively. Those of the Indica-type rough rice varied from 12 MPa. to 42 MPa., and from 15 MPa. to 53 MPa. respectively. 4. Deformations at bioyield point and rupture point ranged from 0.18 mm/min to 0.26 mm, and from 0.28 mm to 0.53 mm respectively. These deformations decreased with an increase in moisture content up to moisture content of approximately 17% (w.b.) and increased again thereafter. 5. Regression equations were developed to predict these mechanical properties for the rough rice kernel as a function of moisture content.

• 대한환경공학회지
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• 제35권11호
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• pp.776-780
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• 2013

본 연구에서는 마이크로파 조사를 통하여 디젤오염토양의 TPH (Total Petroleum Hydrocarbon) 제거양상을 살펴보고자 하였다. 건조토양을 마이크로파로 조사하였을 때 토양 내 온도의 상승은 완만하였으나 수분이 공급된 상태에서 온도 상승이 급격하게 나타났다. 함수량이 20% 이내 범위에서는 수분함량이 증가할수록 온도가 상승하였으나 20% 이상에서는 오히려 온도가 저하되었다. 100~700 W의 전력량으로 마이크로파를 조사한 후 각각의 TPH의 제거량을 확인하였을 때 300 W 이상의 범위에서는 전력량이 높아짐에도 TPH 제거량에 차이가 많지 않았다. 초기 수분량 20%에서 마이크로 조사 시 최종 TPH 제거량은 60%로 나타났으나 추가적으로 수분을 공급하여 토양 내 함수량을 일정하게 유지하였을 때 약 25%의 TPH 제거 증대효과가 나타났다. 이는 마이크로파를 이용할 때 반응이 지속됨에 따라 수분손실과 더불어 온도가 감소하므로 토양 내 함수량을 유지하는 것이 효율적인 TPH제거를 위해 중요한 요인이 될 수 있다는 것을 나타낸다.

• The Korean Journal of Ecology
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• 제23권2호
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• pp.117-123
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• 2000

Changing patterns and the possibility of climate change in the area of Cheiudo island, the southernmost Island in Korea, were analyzed using daily temperature and Precipitation data observed at the Cheiu Regional Meteorological Office from May 1923 to December 1998. A hydrologic simulation model "BROOK" was used to simulate and analyze the dynamics of daily soil moisture content and soil moisture deficit by applying the daily weather data. During the period, significantly increasing pattern was observed in temperature data of both annual and monthly basis, while no significantly changing pattern was observed in precipitation data. During the last 76 years. mean annual temperature was observed to have risen about 1.4$^{\circ}C$, which may show the Possibility of the initiation of climate change on the island whose validity should be tested in future studies after long-term studies on temperature. Based on the simulation, due to increased temperature, significant increase was predicted in evapotranspiration. while no significant decrease was detected in simulated soil moisture content during the period. Changing pattern of annual soil moisture content was markedly different from those of precipitation. In some dominant trees, negative effects of the drought of the late season for the previous year were shown to be statistically significant to radial growth of the tree for the current year. As annual variation of radial growth of trees is mainly affected by the soil moisture content. the information on the dynamics of soil moisture deficit possibly provides us with useful information for the interpretation of tree growth decline on the mountain. mountain.

• Journal of Biosystems Engineering
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• 제40권3호
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• pp.201-211
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• 2015

Purpose: Designing equipment for processing, sorting, and other post-harvest operations of agricultural products requires information about their physical properties. This study was conducted to investigate some of the mechanical and physical properties of Moringa oleifera L. pods and seeds. Methods: Properties such as the length, width, thickness, bulk density, porosity, mass, static coefficient of friction, and angle of repose were determined as a function of moisture content. Statistical data and force-deformation curves obtained at each loading orientation and moisture level were analyzed for bioyield point, bioyield strength, yield force, rupture point, and rupture strength using a testrometric machine. Result: The basic dimensions (length, width, and thickness) of moringa pods and seeds were found to increase linearly from 311.15 to 371.45 mm, 22.79 to 31.22 mm, and 22.24 to 29.88 mm, respectively, in the moisture range of 12 to 49.5% d.b. The coefficient of friction for both pods and seeds increased linearly with an increase in moisture content on all the surfaces used. The highest value was recorded on mild steel, with 0.581 for pods and 0.3533 for seeds, and the lowest on glass for pods, with a value of 0.501, and of 0.2933 for seeds on galvanized steel. The bioyield and rupture forces, bioyield and rupture energies, and deformation of the pods decreased with an increase in moisture content to a minimum value, then increased with further decrease within the moisture content range, while the yield force increased to a maximum value and then decreased as the moisture content increased. Conclusion: These results will help to determine the most suitable conditions for processing, transporting, and storing moringa pods, and to provide relevant data useful in designing handling and processing equipment for the crop.

• 콘크리트학회지
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• 제8권5호
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• pp.163-170
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• 1996

셀룰로우스 섬유는 강도와 강성측면에서 우수하고 동시에 적은 에너지로 가공이 가능하며, 또한 가격 면에서도 유리하고 풍부한 양으로 인해 시멘트의 보강재료로서 적당하다. 셀룰로우스 섬유 시멘트 복합체는 일반적으로 슬러리-탈수 가공에 의해 생산되며 평면이나 곡면 등의 시멘트 복합제품으로 얇은 판을 만드는데 주로 사용되어진다. 본 연구에서는 셀룰로우스 섬유 혼입률과 여러 가지 수분상태에서의 강도 특성을 실험에 의해 고찰하였다. 이들 시멘트 복합체의 강도효과에 대한 실험결과들의 검증을 위하여 통계학적인 분산분석과 다중비교에 의한 분석을 수행하였다. 휨강도는 섬유 혼입률이 약 8%까지 상승할 때 증가하였으며, 휨인성은 섬유 혼입률의 증가에 따라 증가하였다. 수분함유량은 휨강도에 중요한 요인으로 작용하였는데, 수분 함유량의 증가는 휨강도의 감소를 가져온 반면, 휨인성의 증가를 보여주었다. 시멘트 복합체에 포졸란 재료를 사용하였을 경우 수분에 의한 영향은 크지 않은 것으로 나타났으며 약간의 휨인성의 감소와 더불어 휨강도의 증가를 보였다.

• 인간식물환경학회지
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• 제23권3호
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• pp.255-265
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• 2020

Background and objective: The purpose of this study was to provide guidelines for irrigation management by analyzing the effects of soil moisture on the growth characteristics of herbaceous plants in green infrastructure. Methods: In a rain shelter greenhouse, the growth performance of nine species of experimental plants was assessed under different soil moisture contents (20%, 15%, 10%, 5%, and 1%) for about 5 months to analyze plant growth characteristics due to soil humidity. Methods to determine plant growth conditions include surveying growth conditions of the crowns, stems, leaves, flowers and fruits on the aerial part and surveying growth conditions of the roots in the underground part. Results: The results showed that Mukdenia rossii and Astilbe rubra grew well at 15% moisture content with irrigation intervals of 10 and 13 days, respectively. Soil moisture content of 10% with irrigation intervals of 13 and 17 days was appropriate for Sedum kamtschaticum and Pachysandra terminalis. Similarly, Aquilegia japonica and Liriope platyphylla grew well at 15% moisture content with irrigation intervals of 10 and 17 days. However, Ligularia stenocephala grew well-developed stems and roots at 1% soil moisture content and an irrigation interval of 25 days, while the optimum conditions for Lythrum anceps were 5% moisture content and an irrigation interval of 8 days. Conclusion: Although a limited number of experimental plants were used in this study, this study could propose an appropriate irrigation cycle for planting on artificial soil substrates. Based on these results, it is possible to plan suitable planting designs considered irrigation cycles.

• 한국습지학회지
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• 제20권1호
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• pp.27-34
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• 2018

본 연구에서는 멸종위기식물인 큰바늘꽃(Epilobium hirsutum L.)의 효과적인 보전 및 복원을 위한 기초자료를 얻기 위해 토양의 수분함량과 유기물함량이 번식계절과 생리 반응에 어떠한 영향을 주는지에 대하여 알아보았다. 큰바늘꽃은 다년생식물이지만 모든 구배에서 한 해에 생식생장을 하였다. 꽃봉오리, 꽃 그리고 열매주머니는 수분구배와 영양소구배에서 각각 높은 수분 조건과 높은 유기물 조건에서 가장 이른 시기에 성숙하였다. 그리고 꽃 수와 열매주머니 수는 높은 수분 조건과 높은 유기물 조건에서 더 빨리 증가하였다. 엽록소 함량은 수분구배에서 높은 중간 수분 조건과 높은 수분 조건에서 가장 많았고, 영양소구배에서는 차이가 없었다. 최소엽록소형광 값은 수분구배와 영양소구배 모두 차이가 없었고, 최대엽록소형광 값은 높은 수분 조건과 높은 유기물 조건에서 가장 높았다. 광계 II의 광화학적 효율 값은 모든 수분구배에서 0.75로 차이가 없었고, 영양소구배에서의 경우 높은 유기물 조건에서 0.78로 가장 높았다. 큰바늘꽃은 수분이 증가할수록 엽록소 함량이 많아지고, 유기물이 증가할수록 Fv/Fm 값이 높아졌다. 이상의 연구결과는 토양의 충분한 수분과 유기물 함량은 큰바늘꽃의 번식계절을 앞당겨 주고 생식생장을 촉진한다는 것을 보여준다. 추후 멸종위기종인 큰바늘꽃의 개체군 유지와 서식지를 관리하는데 중요한 정보가 될 것으로 판단된다.