• Wind and Structures
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• v.1 no.3
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• pp.203-223
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• 1998

This paper describes in detail the features of an extensive study on Spectral Density Functions (SDF's) of wind pressures acting on several low building roof geometries carried out in a boundary layer wind tunnel. Various spectral characteristics of wind pressures on roofs with emphasis on derivation of suitable analytical representation of spectra and determination of characteristic spectral shapes are shown. Standard spectral shapes associated with various zones of each roof and their parameters are provided. The established spectral parameters can be used to generate synthetic spectra adequate for the simulation of wind pressure fluctuations on building surfaces in a generic fashion.

• Proceedings of the IEEK Conference
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• 2006.06a
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• pp.533-534
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• 2006

This paper presents the architecture design of a high-speed, low-complexity 128-point radix-$2^4$ FFT processor for ultra-wideband (UWB) systems. The proposed high-speed, low-complexity FFT architecture can provide a higher throughput rate and low hardware complexity by using 2-parallel data-path scheme and single-path delay-feedback (SDF) structure. This paper presents the key ideas applied to the design of high-speed, low-complexity FFT processor, especially that for achieving high throughput rate and reducing hardware complexity. The proposed FFT processor has been designed and implemented with the 0.18-m CMOS technology in a supply voltage of 1.8 V. The throughput rate of proposed FFT processor is up to 1 Gsample/s while it requires much smaller hardware complexity.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.5
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• pp.769-777
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• 2016

The objective of this study was to evaluate the stream depletion from groundwater pumping in deep aquifer using the Ward and Lough's analytical solution (2011) which considers a two-layer leaky aquifer system. The calculated results for each pumping from the 110 wells beside streams showed a wide range of non-dimensional stream depletion, that is the streamflow depletion rate divided by the groundwater pumping rate, from lower than 0.1 to more than 0.9 on average for 5 years depending on the specific properties of well location. From the comparison with Hunt's solution (1999) of a single layer aquifer, the Ward and Lough's solution showed about 50% lower than the Hunt's solution due to the difference of hydraulic properties between the first and second layers as well as the lagged effect of vertical leakance. It was also found that the groundwater pumping has a minor effect on the stream depletion if the stream depletion factor (SDF) of the 1st layer is higher than about 1,000 or the SDF of the 2nd layer is higher than about 100, or the vertical leakance is smaller than $10^{-5}s^{-1}$. Furthermore, in the present study, the variations of the stream depletion were assessed according to the magnitude of unmeasured hydraulic properties such as transmissivity and storage coefficient of the 1st layer, vertical hydraulic conductivity of the 2nd layer, the streambed hydraulic conductance.

• The Korean Journal of Food And Nutrition
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• v.23 no.4
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• pp.516-525
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• 2010

Flaxseed has recently gained attention as a functional food. In this paper, physicochemical analyses of flaxseed and its oil were performed. Crude fat content ranged from 37~43%, moisture 0.2~6.8%, carbohydrate 30~35%, crude protein 18~23%, and crude ash 3~4%. Flaxseed is also an important source of dietary fiber. The TDF(total dietary fiber) contents of the flaxseed samples were 28~31%, and the SDF(souble dietary fiber) content of roasted flaxseeds was higher than that of raw flaxseeds. The major minerals found in flaxseed were calcium, potassium, magnesium, and phosphate. The flaxseeds were rich in ${\gamma}$-tocopherol with 234.3 mg/kg in raw brown flaxseed and 134.1 mg/kg in raw gold flaxseed, respectively. Roasted flaxseeds showed slightly lower vitamin and amino acid contents than those of the raw samples. The iodine, saponification, and acid values of brown flaxseed oil were 204.1 g/100 g, 193.6 mg/g, and 1.59 mg/g, and for gold flaxseed oil were 203.0 g/100 g, 189.9 mg/g, and 2.35 mg/g, respectively. ${\alpha}$-Linolenic acid(ALA, C18:3n-3) was highly concentrated in the flaxseed oil, which constituted about 55.5~56.1% of total fatty acids. Thus, flaxseed oil is a good source of omega-3 fatty acids and beneficial for the heart. Flaxseed contains high levels of dietary fiber including lignans, as well as minerals and vitamins, which may have antioxidant actions and help protect against certain cancers.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.371-377
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• 1996

Potential health promoting effects such as antiallergic, anti-inflammatory, antiviral, anticancer and anticarcinogenic properties have been ascribed to citrus flavonoids. Dietary fibers have also been used as functional food components due to the various beneficial physiological activities. Two kinds of flavonoids, naringin and hesperidin, were identified both in the pulp and in the peel of Korean tangerine. The contents of naringin and hesperidin in the pulp were 2.95 mg/100 g and 0.53 mg/100 g, respectively. However, the contents of naringin and hesperidin in the peel were much higher (10.77 mg/100 g and 38.90 mg/100 g) thanthose of two identified flavonoids in the pulp. The content of soluble dietary fiber (SDF) in the pulp of tangerine was 1.90%, insoluble dietary fiber (IDF) 0.37%, and total dietary fiber (TDF) 2.27% based on wet matter, respectively. The content of SDF was 1.09%, IDF 4.77% and TDF 1.86% in the peel of tangerine. The total pectin content was 1.53% in the pulp and 0.94% in the peel of tangerine. The peel of Korean tangerine, a by product in tangerine processing, would be a good source for the production of naringin, hesperidin and pectin.

• Journal of Korea Water Resources Association
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• v.49 no.11
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• pp.923-930
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• 2016

This study was to evaluate the stream depletion from groundwater pumping in shallow aquifer using the Hunt's analytical solution (2009) which considers a two-layer leaky aquifer-stream system. From the total 2,187 cases of simulations with combinations of various aquifer and stream properties, the streamflow depletion rates divided by the groundwater pumping rate showed the low values when the stream depletion factor (SDF) is higher than 1,000-10,000, and was more sensitive to the aquitard hydraulic conductivity than the streambed hydraulic conductivity. The comparison of the Hunt's solution (2009) with the Hunt's solution (1999) of a single layer aquifer indicated that the maximum difference between the dimensionless stream depletions calculated by using both solutions is above 0.3, and the stream depletion is significantly affected by the hydraulic properties of the $2^{nd}$ layer as the SDF of the first layer increases. The Hunt's solution (2009) was applied to the real shallow groundwater well that is located in Chunju-Si, and the results revealed that the groundwater pumping has significant effects on streamflow in a short period of time, showing that the dimensionless stream depletion exceeds 0.8 within a few days. It was also found that the shallow groundwater pumping effects on stream depletion are highly dependent on the stream-well distance for the locations with high hydraulic diffusivity of $1^{st}$ layer and low vertical leakance between $1^{st}$ and $2^{nd}$ layers.

• Korean Journal of Food Science and Technology
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• v.31 no.6
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• pp.1434-1439
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• 1999

The chemical characteristics of flesh and pomace of Japanese apricot were investigated. The moisture contents of flesh and pomace of Japanese apricot were 89.94% and 91.39%. Free sugars and sugar-derivatives of Japanese apricot flesh (JAF), were 0.77% glucose, 0.47% fructose, 0.35% mannitol and 0.47% sorbitol, and of Japanese apricot pomace (JAP) were 0.01% glucose, 0.09% fructose, 0.38% mannitol and 0.06% sorbitol, respectively. The organic acids of flesh and pomace of Japanese apricot were citric acid, malic acid and oxalic acid. The predominant minerals in flesh and pomace of Japanese apricot were K, P, Ca and Al. The contents of dietary fiber (DF) in JAF were 2.94% of insoluble dietary fiber (IDF), 1.07% of soluble dietary fiber (SDF) and 4.01% of total dietary fiber (TDF). IDF of JAP were 6.25%, SDF 0.51% and TDF, 6.76%.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.28-31
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• 2005

To extract apple pectins, apple pomace (AP) was extruded under 14 different conditions of screw speed (250-350 rpm), feed rate of 30-40 kg/hr, and 20-30% moisture content using twin-screw extrusion. Response surface methodology (RSM), based on three variables by three-level factorial design, was employed to investigate effects of screw speed, feed rate, and moisture on dependent variables of extrudates, soluble dietary fiber (SDF), yield of anhydrogalacturonic acid ($Y_{AGA}$) representing pectin, and intrinsic viscosity ([${\eta}$]). Second order models were used to generate three-dimensional response surface for dependent variables, and their coefficients of determination ($R^2$) ranged from 0.96 to 0.99. Moisture content showed highest effect on solubilization of AP.

• Journal of Nutrition and Health
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• v.26 no.2
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• pp.196-201
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• 1993

In this study, dietary fiber contents in vegetables and seaweeds were determined by Mongeau-Brassard method and the AOAC official method. The average total dietary fiber(TDF) contents by AOAC official method were 6% for vegetables, and 33% for seaweeds. The average ratios soluble dietary fiber (SDF) contents to TDF contents were 47% for vegetables and 57% for vegetables except bellflower root and 1.0% - 8.0% for seaweeds. TDF$\pm$error boundary values by Mongeau-Brassard method were a little higher than those by AOAC official method. But, F/Fc of all samples were lower than 1.0. Therefore, Mongeau-Brassard method was evaluated as precisely as AOAC official method.

• Journal of the Korean Society of Food Science and Nutrition
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• v.27 no.3
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• pp.376-380
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• 1998

The chemical copositions in rice hulls of twenty six varieties which are one of the largest agricultural by-products in Korea were analyzed. The chemical compositions were 8.56~9.70% moisture, 10.01~17.16% ash, 44.02~55.50% crude fiber, 0.26~2.90% crude protein, 9.20~14.50% starch, and 0.28~0.69% lipid. There were no significantly difference in chemical compositions among twenty six varities. The mineral contents(mg/100g) were 14.3~392.4mg K, 59.4~389.1mg Ca, 31.78~377.8mg Zn, 19.4~104.4mg Na, 12.9~47.6mg Mg, 12.8~37.0mg Si, 8.3~30.5mg Fe, 7.9~26.1mg Al, 7.6~23.5mg Mn, and 6.3~40.3mg P. The contents of IDF (insoluble detergent fiber), SDF(soluble detergent were 70%, 1~2%, 67~73%, 51~60%, 11~17% and 0.3~2%, respectively. The lignin content was higher in Hwa-Young and Mankum than in others. The amounts of ethanol extracts of rice hulls were 1.01~1.52%. In conclusion, the chemical compositions were not significantly difference among twenty six rice hulls varieties.