• Journal of Biosystems Engineering
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• 제12권1호
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• pp.39-44
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• 1987

Measurement methods of moisture content were compared with 7 dried vegetables (red pepper, onion, green onion, garlic, ginger, carrot and radish). The moisture contents of dried vegetables having different moisture contents were determined by atmospheric oven drying, infrared balance, vacuum oven and Karl Fisher methods. Vacuum oven and Karl Fisher methods gave the relatively agreed results and considered to give the accurate moisture content. Atmospheric oven drying and infrared balance methods resulted in higher moisture content than methods mentioned above, because of the thermal decomposition of solid. Calibration of the moisture data of atmospheric oven drying method into the vacuum oven data was undertaken. The thermodecomposable solid fraction was high in onion, radish, green onion and carrot, and was in the range of 8.0-11.7% of the total solid in these products.

• 한국식품영양과학회지
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• 제20권5호
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• pp.509-512
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• 1991

Rheological property and apparent viscosity(η)of several semi-solid foods were measured with extrusion capillary viscometer. Apparent viscosities of several semi-solid foods ranged from 0.2714 Pa.s to 2.6453 Pa.s Rheological property of spread type semi-solid foods was pseudoplastic (with yield value). Especially, as the moisture content and temperature of Chungkook-jang spread increased, apparent viscosity decreased. On the contrary, as the added soybean oil content of Chungkook-jang spread increased, apparent viscosity also increased.

• 한국응용과학기술학회지
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• 제22권4호
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• pp.371-378
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• 2005

In the previous study, three kinds of monomers and the functional monomer, acetoacetoxyethyl methacrylate (AAEM), which could improve the film property and cross-linkage, were polymerzied into acrylic resin copolymers (HSA-98-20, HSA-98-0, HSA-98+20) containing 80% solid content. In this study, the high-solid coatings(HSA-98-20C, HSA-98-0C, HSA-98+20C) were prepared by the curing reaction between acrylic resins containing 80% solid content and isocyanate at room temperature. Various properties were examined for the film coated with the prepared high-solid coatings. The introduction of AAEM in the coatings enhanced the abrasion resistance and solvent resistance of coatings, which indicated the possible use of high-solid coatings for top-coating materials of automobile. The curing times measured by viscoelastic measurement were 350, 264, and 212 min for HSA-98-20C, HSA-98-0C, and HSA-98+20C, respectively. This shows that the curing times become shorter with increasing $T_g$ values.

• 농업과학연구
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• 제39권3호
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• pp.413-420
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• 2012

Spectroscopic measurement method based on visible and near-infrared wavelengths was prominent technology for rapid and non-destructive evaluation of internal quality of fruits. Reflectance measurement was performed to evaluate firmness, soluble solid content, and acid content of truss tomatoes by hyperspectral reflectance imaging system. The Vis/NIR reflectance spectra was acquired from truss tomatoes sorted by 6 ripening stages. The multivariable analysis based on partial least square (PLS) was used to develop regression models with several preporcessing methods, such as smoothing, normalization, multiplicative scatter correction (MSC), and standard normal variate (SNV). The best model was selected in terms of coefficient of determination of calibration ($R_c^2$) and full cross validation ($R_{cv}^2$), and root mean standard error of calibration (RMSEC) and full cross validation (RMSECV). The results of selected models were 0.8976 ($R_p^2$), 6.0207 kgf (RMSEP) with gaussian filter of smoothing, 0.8379 ($R_p^2$), $0.2674^{\circ}Bx$ (RMSEP) with the mean of normalization, and 0.7779 ($R_p^2$), 0.1033% (RMSEP) with median filter of smoothing for firmness, soluble solid content (SSC), and acid content, respectively. Results show that Vis / NIR hyperspectral reflectance imaging technique has good potential for the measurement of internal quality of truss tomato.

• 센서학회지
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• 제18권6호
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• pp.441-448
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• 2009

Magnesia partially stabilized zirconia(Mg-PSZ) solid electrolytes for an improvement of thermal shock resistance, which is suitable for the measurement of oxygen activity in a molten steel, were prepared by post-thermal aging treatment. The steelmaking oxygen sensor elements were formed by an injection molding method, sintered at $1650^{\circ}C$, and then thermal aged ranged from 1250 to $1400^{\circ}C$. Sintered density and porosity were decreased as increasing the magnesia content in a zirconia-magnesia solid solution. Fractions of cubic phase to the synthesized Mg-PSZ solid electrolytes were ranged from 13.13 to 79.54.% after post-thermal aging treatment. Very dense microstructure without voids in the grains was obtained by the post-thermal aging process. Fine tetragonal phase crystallites precipitated on the cubic surface during post-thermal aging up to $1300^{\circ}C$ improve a thermal shock resistance and reappearance of electro motive force(EMF) curve.

• 한국안전학회지
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• 제29권4호
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• pp.123-131
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• 2014

Whole amount of waste water, approximately 921.6 liter, for cleaning a ready mixed concrete truck should be used to produce concrete as a mixing water or cleaning water. Recycling water for concrete mixing contains solids, which cause decrease in slump, air and compressive strengths, so it may influence on poor concrete quality. Therefore, it has been maintained to use recycling water with less than 3 percent of solids. Since no evaluation system has been constructed to directly reflect on variability of recycling water from ready mixed concrete plants, it is necessary to develop "Automatic recycling solid measuring system" for quality controls in real time. In this research, sensors measuring waste water concentration in ultrasonic and inductance methods were developed, and automatic system using the sensors were established. The accuracy of measurement sensors developed for recycling water based on various conditions of concentration was proved, and application limits were evaluated. Also, concentration of recycling water using sensors developed from ready mixed concrete plant was measured, and curing method verified the accuracy of the sensors. Moreover, measurement sensors for recycling water in various locations were installed to evaluate the effects on measuring method and spots. The automatic measuring system for recycling water concentration, which is developed in the research, will contribute to improve concrete quality safety through reliable solids maintenance.

• Journal of the Korean Wood Science and Technology
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• 제44권6호
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• pp.864-871
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• 2016

This study was conducted to compare and analyze gross calorific values from measurement methods of lignocellulosic biomass and calculation data from calorific value prediction models based on the elemental content. The deviation of Liriodendron tulipifera (LT) and Populus euramericana (PE) was shown 7.7 cal/g and 7.4 cal/g respectively in palletization method, which are within repeatability limit 28.8 cal/g of ISO FDIS 18125. In the case of Thailand charcoal (TC), nontreatment method and palletization method was satisfied with repeatability limit as 22.8 cal/g and 8.8 cal/g respectively. Seowon charcoal (SC) was shown deviation of 11.4 cal/g in nontreatment method, because the density and chemical affinity of sample increases as the carbon content increases from heat treatment at high temperature in the case of TC and SC. In addition, after applying the elemental content of each of these samples to the calorific value prediction models, the study found that Model Equation (3) was relatively consistent with measured calorific values of all these lignocellulosic biomass. Thus, study about the correlation between the density and size of particle should be conducted in order to select the measurement method for a wide range of solid biofuels in the future.

• 콘크리트학회논문집
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• 제27권6호
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• pp.695-703
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• 2015

콘크리트용 화학혼화제의 인수검사 시험법에 대한 국내외 기준을 살펴보고, 한국도로공사에서 활용 중인 고형분량을 대상으로 다자비교시험에 의한 통계분석을 통하여 시험법의 신뢰성을 검증하였다. 또한 FT-IR을 활용하여 다성분 조성 화학혼화제의 기기분석 효용성을 검증하였다. 시험결과의 이상치를 검정하는 Cochran, Grubbs 및 Dickson의 Q 검정을 실시하였으며, KS A ISO 5725-2의 절차에 따른 재현표준편차 및 반복표준편차는 각각 0.25 및 0.09%으로 나타나 시험방법의 신뢰성을 확인할 수 있었다. 또한 혼화제 시료상태에 따라 FT-IR 특성피크가 큰 차이를 나타내므로 건조시료에 의한 관리가 필요하였으나, 2종 이상 원료가 포함된 다성분 혼화제의 FT-IR 특성피크는 큰 차이가 없어 기기분석의 효용성을 확인할 수 없었다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제27회 추계학술대회논문집
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• pp.255-263
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• 2006

In order to measure the acoustic amplification factor of an Al/HTPB propellant, T-burner tests using pulsed DB/AB method were conducted. In the experiment, powdered aluminum content was varied to a certain extent. Simultaneous ignition on the internal surface of a propellant was achieved by the use of a fast ignition disk. From the experimental data, the damping factor for a non-zero aluminum content could not be calculated due to the fast attenuation of perturbed pressure. Therefore, the addition of aluminum particle was more than sufficient to stabilize pressure-coupled instability.

• 접착 및 계면
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• 제10권4호
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• pp.174-181
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• 2009

고 고형분 점착제의 점도 개선을 위해 seed 중합을 이용하여 수용성 저점도 점착제를 중합하였다. Seed 바인더 중합 중 최적 중합 조건을 산출하고, 점착제 중합 시 seed 바인더와 acrylic acid의 함량을 변화시켜 점도변화와 피착면에 대한 점착박리강도를 측정하여 다음과 같은 결과를 얻었다. 점착제 중합에서 seed 바인더의 함량이 7 wt%/monomer일 때 60%의 고형분에서 2,100 cps의 낮은 점도를 나타내고 평활한 점착제 필름을 제조할 수 있었다. Acrylic acid함량 변화에 따른 기계적 물성 측정에서는 4 wt%/monomer의 acrylic acid를 사용 했을 때 우수한 점착박리강도와 유지력을 나타내었다.