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The degree of maturity of rice greatly affects the quality of the rice, including factors such as the integrity of grains, color, and the nutritive components. Green Rice ® is rice (Oryza sativa L.) that has been harvested earlier than brown rice and appears green in color. To determine suitable harvesting time of the Jinbu variety of Green Rice ® in Gyeonggido, rice samples harvested on 23, 26 and 42 days after heading (DAH) were compared on their yield, color intensity, and proximate compositions. The maximum paddy yield of Green Rice ® was 61.4% at 23 DAH, which decreased to 45.4%, 5.5% at 26 and 42 DAH, respectively. Greenness was darker at 23 DAH (-0.27±0.03), and significantly weaker (p＜0.05) at 26 DAH (0.07±0.01) and at 42 DAH (5.25±0.08). All proximate compositions, except carbohydrate, including moisture, crude fat, protein, ash and total minerals were higher in the earlier-harvested Green rice ® than in brown rice, without variations among the 23 and 26 DAH Green rice ® . Overall, the optimum harvest time of Jinbu Green Rice ® at Gyeonggido would be 23 DAH. We suggest that timely harvesting could be a potent determinant of the quality of Green Rice ® .

This study was performed to determine the most appropriate thin layer drying model and the effective moisture diffusivity of rapeseed. The thin layer drying tests were conducted at three different combinations of drying air temperature levels of 40, 50, and 60 °C and relative humidity levels of 30, 45, and 60%. The thin layer drying characteristics of rapeseed were determined. The Page (1949) model was the most adequate model for describing the thin layer drying of rapeseed. Drying occurred in the falling rate period and the rate of moisture removal from rapeseed was governed by the rate of water diffusion to the surface of the seed. Effective moisture diffusivities were calculated based on the diffusion equation for a spherical shape using Fick’s second law. Effective moisture diffusivity during drying varied from 1.72 × 10−11 to 3.31 × 10−11 m2 s−1 over the temperature range. The dependence of moisture diffusivity on temperature was described by an Arrhenius-type equation. The activation energy for moisture diffusion during drying was 28.47 kJ mol−1.

In this study, computer simulations were conducted to assess the use of a circulating concurrent-flow dryer for rapeseed drying and to determined the effect of this drying method on the germination ratio of rapeseed after the drying process was complete. The simultaneous heat and mass transfer between air and rapeseed in a concurrent-flow dryer was examined by simulation. The drying simulation was based on several parameters with sequent time series. Equations concerning air psychrometrics, physical properties, thermal properties, equilibrium moisture content, thin layer drying of rapeseed, etc. were all combined to solve the simulation models. Based on energy and mass transfer in the concurrent-flow drying model, a simulation program for the circulating concurrent-flow rapeseed dryer was built along with a detailed description of the mathematical solution to the model. A pilot scale circulating concurrent-flow dryer(200 kg/batch) was used to verify the fitness of the simulation program. A comparison between the experimental data and the model predicted results was presented and discussed. The drying parameters and germination ratio were analyzed and the accuracy of the simulation program was evaluated. The simulation program proved to be reliable and was shown to be a convenient tool for predicting rapeseed drying and germination ratio of rapeseed in a concurrent-flow dryer.

Minimizing artifacts from skin movement is vital for acquiring more accurate kinematic data in human movement analysis. There are several stages that cause skin movement artifacts and these stages depend on the selection of the reference system, the error reduction method and the coordinate system in clinical gait analysis. Due to residual errors, which are applied to the Euler and Bryant angle methods in each stage, significant cumulative errors are generated in the motion analysis procedure. Thus, there is currently a great deal of research focusing on reducing kinematic errors through error reduction methods and kinematic error estimations in relation to the reference system. However, there have been no studies that have systematically examined the effects of the selected coordinate system on the estimation of kinematic errors, because most of these previous studies have been mainly concerned with the analysis of human movement using only the human models that are provided in the commercial 3D motion capture systems. Therefore, we have estimated the differences between the results of human movement analyses using an absolute coordinate system and a relative coordinate system during a gait, in order to establish which system provides a more accurate kinematic analysis at the ankle joint. Six normal adult subjects with no neurological or orthopedic conditions, lower extremity injuries, or recent history of lower extremity surgery were used in this study. The analysis was con- ducted at a walking speed of 1.35m/s. For the clinical estimation, we used a cardinal plane based on the segmental reference system and the differences were plotted on the planes. From this analysis, when a relative coordinate system was in the gait analysis, the average kinematic error occurring during the gait was determined to be 13.58mm, which was significantly higher than the error generated with an absolute coordinate system. Therefore, although the relative coordinate system can also be used to calculate the ankle joint center during the clinical gait analysis, the absolute co- ordinate system should be employed in order to obtain more accurate joint kinematic data. In addition, the results from this study can be used as a basis to select an appropriate coordinate system with regards to the diagnostic accuracy level required for various kinds of gait disorders.

The effective moisture diffusivity and its dependence on drying temperature during drying of rapeseed were experimentally investigated. The data were recorded from thin layer drying experiments at nine different combinations of drying air temperatures of 40, 50, and and the relative humidities of 30, 45, and 60%. The moisture diffusion equation was analyzed using stepwise multiple regression analysis. Effective moisture diffusivities were calculated based on the moisture diffusion equation for a spherical shape using Fick`s second law. The effective diffusivities during the drying of rapeseed were , and at 40, 50 and , respectively. The activation energy for moisture diffusion during drying was . The dependence of moisture diffusivity on temperature was described by an Arrhenius-type equation. Drying occurred in the falling rate period and the internal moisture diffusion phenomenon is the governing physical mechanism of the moisture movement in the particles.

This study was performed to determine desorption equilibrium moisture contents(EMC) of rapeseed grown in Korea. EMC values were measured by static method using saturated salt solutions at three temperature levels of 30, 40 and , and eight relative humidity levels in the range from 11.0 to 83.6%. The measured EMC values were fitted to Chung-Pfost, Modified Halsey, Modified Henderson and Modified Oswin models by using nonlinear regression analysis. The results of root mean square errors for four models showed that Halsey and Modified Oswin Models could serve as good models, but the Chung-Pfost and Modified Henderson models could not show reasonably good fitting.

This study was conducted to find out effects of abnormal kernels of 0 to 30% in brown rice on quality characteristics during milling using friction type test mill. The average hardness values of abnormal and normal brown rice kernels were 6.52 kg, 8.48 kg, respectively. According to the increase of abnormal kernels in brown rice, grain temperature, required electrical energy, the broken kernels ratio, and the weight of solid matter on the surface of milled rice were increased due to crush of the abnormal kernels during milling, which proves that abnormal kernels in brown rice should be removed before milling to improve milling characteristics.

A one-dimensional heat conduction problem in cylindrical coordinate system was solved using Crank-Nicolson finite difference method to predicting the temperature distribution in rice storage bin with wall insulator. The model can simulate the grain temperatures in insulated round bins using the input data of initial grain temperature. ambient air temperature, wind velocity, solar radiation on a horizontal surface, and thermal properties of grain, bin wall, wall insulator, insulator cover, and air. Temperatures were collected at the bin center, 0.65m in radial direction from the center, and near the bin wall in 2.7m diameter bin filled with rough rice to depth of 3.0m were used to validate the simulation model. Grain temperatures predicted by the model were in very good agreement with the measured temperatures. The residual mean square error between measured and predicted grain temperatures at the bin center was .