• Journal of Animal Science and Technology
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• v.62 no.1
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• pp.74-83
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• 2020

Organic waste used as a feedstock in the anaerobic digestion (AD), it includes carbon and nitrogen. Carbon and nitrogen have an effect on the various digestive characteristics during AD, however, the study is rare about those of the interaction. This study investigates the influence of carbon type and carbon to nitrogens (C/N ratios) on the AD characteristics of organic waste. Experimental treatments involved a combination of three carbon types with three C/N ratios. The AD tests were carried out using a 125-mL serum bottle at a constant temperature of 37℃ and moisture 95% for 18 days. Degradation pattern shows the difference among three-carbon treatments, the starch group was faster than other groups. Maximum methane production date was similar between starch (9.96 ± 0.05 day) and xylan group (10.0 ± 0.52 day), those of the cellulose group (14.6 ± 1.80 day) was slower than other groups (p < 0.05). The lag phase was only affected by the carbon type (p < 0.05). Ammonia nitrogen was mainly affected by nitrogen concentration regardless of carbon type (p < 0.05). This study showed that xylan is useful as feedstock in order to decrease the lag phase, and it showed that ammonia was independently affected by the nitrogen concentration.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.20 no.9
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• pp.608-613
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• 2008

The purpose of the present paper is to investigate the effect of outdoor weather conditions on the performance of a heat recovery ventilator. Experiments have been performed by varying outdoor temperature/humidity conditions with the indoor conditions fixed at the standard conditions by KARSE. Results indicate humidity efficiency shows larger uncertainties than temperature efficiency in general. With the heat generation by an internal fan removed, the modified temperature efficiency remains almost constant regardless of the indoor-outdoor temperature difference. The enthalpy efficiency can have very large or negative values in case the outdoor conditions are in the vicinity of the indoor enthalpy line. The direction of heat flow, in such a case, can be opposite to that of moisture flow between two air streams. Discussions are included about various interesting features of the psychrometric processes taking place in a heat recovery ventilator.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.224.1-224
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• 2003

The production of black rice in Korea has been increasing, as more Koreans are tending to blend black rice with medium-grain rice for serving. This increased production creates an opportunity for developing new products. In this study, the properties of sponge cakes produced from a blend of black rice flour (BRF) and wheat flour (WF) are investigated. Black rice sponge cakes (BRSC) were produced with constant process variables (e.g. baking temperature, fermentation time and BRP content (10, 20 & 30%)). Proximate compositions, farinogram, amylogram and extensogram analyses of BRSC were determined by AACC method. BRSC color was expressed to Hunter L, a and b values using a colorimeter. Sensory properties were evaluated by a trained 5-member panel. Moisture contents in BRSC decreased with increasing contents of BRF, while ash and protein contents were increased. Farinograph and amylograph data did not differ significantly between treatments, while extensograph data decreased with increasing BRF contents. With increasing BRF contents, Hunter L value decreased, while Hunter a value increased. When using 20% of BRP, sensory scores of BRSC were the highest in color, flavor and taste. In conclusion, 20% of BRF would be the optimum amount for producing sponge cake with BRP and WF.

• Journal of the Korean Geophysical Society
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• v.2 no.3
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• pp.225-233
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• 1999

Electrical resistivity of a rock-sample is dependant on not only formation factor of rock itself but also many parameters such as fluid type, measuring device, temperature, water saturation, electrical contact between electrode and core section, induced polarization, and frequency of electric source. In this study, we attempt to verify various affecting factors in core resistivity measurements and to find a better environment for core resistivity measurement. Particularly great attention has been paid to understanding the effects of temperature, water saturation, contact condition between sample and electrodes, and frequency of electric source. Precise measurement of resistivity can be achieved by utilizing silver paste for better contacts, taping samples for constant moisture contents, and using time-series resistivity data.

• Food Science and Preservation
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• v.5 no.2
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• pp.138-143
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• 1998

The stowage effects of Satsuma mandarin(Citrus unshiu Marc. var. miyagawa) were investigated by selecting various pretreatmnents; non-tested, wax-coating, paper packaging, 0.02mm cryovac film packaging. Weight loss of film packaging was the lowest among that of others, but decay radio was increased highly at late stages of storage. Soluble solids, moisture content of peel and total sugar were maintained almost constant, but acid content, vitamin C and firmness were reduced gradually during storage at room temperature. For 100 days storage, losses from weight and decay of ton-treated, paper packaging, wax-coating and film packaging were 15.9%, 18.5%, 17.4% and 12.9%, respectively. Acid content was decreased loom 1.28% to 0.81∼0.91% after 100 days storage. Ethylene evolution was increased in a degree after 65 days storage, and the amount was increased repidly afer 115 days. it seemed to be derived from decayed fruits and physiological activities. CO2 content of inner part of fruits was increased between 40∼100 days after storage. Optimum storage period of early variety of Satuma mandarin was regarded for 100days on the basis of appeareance and taste.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.11a
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• pp.501-504
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• 2004

This paper proposes degree of hydration based shrinkage prediction model of 40MPa HPC. This model shows degree of hydration which is defined as the ratio between the hydrated cement mass and the initial mass of cement is very closely related to shrinkage deformation. In this study, degree of hydration was determined by CEMHYD-3D program of NIST. Verification of the predicted degree of hydration is performed by comparison between test results of compressive strength and estimated one by CEMHYD-3D. Proposed model is determined by statistical nonlinear analysis using the program Origin of Origin Lab. Co. To get coefficients of the model, drying shrinkage tests of four specimen series were followed with basic material tests. Testes were performed in constant temperature /humidity chamber, with difference moisture curing ages to know initial curing time effect. Verification with another specimen, collected construction field of FCM bridge, was given in the same condition as pre-tested specimens. Finally, all test results were compared to propose degree of hydration based model and other code models; AASHTO, ACI, CEB-FIP, JSCE, etc.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.39 no.3
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• pp.52-59
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• 2007

This paper confirms that high solid coating can increase coating speed and reduce drying cost. Low solid coating color with the synthetic thickener and high solid coating color with the rheology modifier and with higher ratio of GCC were prepared. Coated paper was then produced with an industrial coater, varying coating speed and dryer temperature in order to keep the moisture content of the coated paper constant. Coating color concentration was able to be increased from 66% to 69% and from 68% to 71% without an adverse effect on coating color rheology. With a help of the rheology modifier, the increased ratio of GCC in high solid coating did not show harmful effects on the coated paper quality.

• Korean journal of food and cookery science
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• v.10 no.3
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• pp.267-276
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• 1994

Recent epidemological observations suggested beneficial effects of dietary fiber on man's health. With the increased emphasis placed on the requirement for dietary fiber in the diet, there has been greater interest in successfully incorporating dietary fiber into food products. Hence, in this study, several dietary fibers such as cellulose, pectin, rice bran, barley bran and job's tears bran were incorporated into julpyun to determine their effects on some physical properties and sensory characteristics. Difference of water binding capacity(WBC) was found among dietary fiber sources. The WBC of pectin was highest and that of job's tears bran was lowest. The moisture contents of julpyun were increased as WBC of added dietary fiber sources was higher. In the rheometer measurement for julpyun added with dietary fiber, hardness of julpyuns added with cellulose and pectin was low. But, hardness of julpyun added cellulose was increased rapidly during storage at 4$^{\circ}C$. Springiness and gumminess wereshowed similar aspects to hardness. In the retrogradation speed by Avrami equation, the rate constant of julpyun added barley bran was low ao retrogradation occurred slowly. The results of sensory evaluation, julpyun added no dietary fiber showed good overall preference. Overall preference in sensory evaluation showed positive correlation with the after-swallowing and color.

• Journal of the Korean Society of Food Culture
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• v.34 no.5
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• pp.612-619
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• 2019

This study assessed the quality characteristics of cookies made with different amounts (0, 5, 10, 15%) of black carrot powder. The density and pH value of cookie dough were constant for all groups. Compared to the control group, the moisture content was higher in groups containing the black carrot powder. Increasing the amount of black carrot powder resulted in decreased L-value but increased a-value. Furthermore, the hardness of cookies increased with increasing amounts of black carrot powder. The consumer acceptance test revealed that up to 15% black carrot powder addition was desirable. Total phenol content of the control group was 24.0 mg GAE/100 g, while black carrot powder groups ranged from 45.5 to 103.5 mg GAE/100 g. The DPPH radical scavenging activity was also augmented with increasing volumes of black carrot powder. Taken together, we recommend that cookies with 15% black carrot powder are desirable in terms of overall acceptability and antioxidant activity.

• Food Science and Preservation
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• v.2 no.1
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• pp.195-202
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• 1995

An experiment was conducted to develop the simple methods of ginger storage which decrease the weight reduction and maintain good quality of ginger during the cellar storage. The stored boxes with volume of 0.03㎥ and ventilator diameter of 3, 4, 5cm was hurried under the ground(60, 80, 100cm) in the green house. During the cellar storage at the 100cm depth the average temperature and relative humidity in the stored box were remained in 11.7~16.3$^{\circ}C$ and 73%, respect. The higher storage amount and smaller size of ventilator size increased the CO2 concentration in the stored box, and the concentration in the stored box with 50% storage quantity rate and 3cm ventilator diameter size was more than 10% for about 2 months from early Feburary. The decay rate of ginger during the cellar storage increased with higher amount of storage quantity and smaller size of ventilator. The CO2 concentration was low and remained relatively constant with the deeper location of stored box under the ground, and the decay rate was lower in the deeper stored box. Germination rate increased with the deeper location of stored box, and with the lower storage quantity and larger ventilator size. The germination rate was low in the higher decay rate box. Weight loss, total sugar and moisture contents of ginger were decreased, while crude fiber and ash were increased during the storage.