• Journal of Biosystems Engineering
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• v.1 no.1
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• pp.17-48
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• 1976

In analyzing the operational characteristics of a rice whitening machine, the internal radial pressure of the machine was measured using strain gage equipment. Changes in cylinder and feed screw configurations, screen type, cylinder speed and counter-pressure levels were examined to determine their impact on the quality and quantity of milled rice and the performance of the machine. The results are summarized as follows: 1. The internal radial pressure in the whitening chamber varied with the surface condition of the grain being processed. During the first or second pass through the machine, pressure was relatively low, reached a maximum after two to three passes with combinations I and II, three to six with combination III and then began to fall. 2. The pitch of the feed screw and the size of the feed gate opening which determine the rate of entry of grain into the whitening chamber, appeared to be the most important factor aff-::cting the degree of radial pressure, quality and quantity of milled rice and the efficiency of the machine. Using a feed screw with a wide pitch (4.8cm), radial pressure was relatively high and head rice recovery ratio \vere quite low. In this case capacity and machine effic\ulcorneriency were much higher than obtained when using a feed screw with a narrow pitch (2.3cm). Very significant responses in radial pressure, head rice recovery rates and machine capacity were observed with changes in cylinder speed and counter-pressure levels when using the wide pitch feed screw. 3. The characteristics of the screen which surrounds the whitening chamber had an important effect on whitening efficiency. The existence of small protuberances on the original screen resulted in significant increases in both machine capacity and efficiency but without a significant decrease in head rice recovery or development of excessive radial pressure. Further work is required to determine the effects of screen surface conditions and the shape of the cylinderical steel roller on the rate of bran removal, machine efficiency and recovery rates. The size of the slotted perforations 0:1 the screen affects total milled rice recovery. The opening size on the original screen was fabricated to accommodate the round shape of Japonica rice varieties but was not suitable for the more slender Indica type. Milling Indica varieties with this screen resulted in a reduction in total milled rice recovery. 4. An increase in cylinder speed from 380 to 820 rpm produced a positive effect on head rice recovery for all machine combinations at every level of counter-pressure used in the tests. Head rice recovery was considerably lower at 380rpm using a wide screw pitch when compared to the results obtained at speeds from 600 to 820 r.p.m. The effects of cylinder speed On radial pressure, capacity and machine efficiency showed contrasting results, depending on the width of the feed screw pitch. With a narrow feed screw pitch (2.3cm), a direct proportional relationship was observed bet\ulcornerween cylinder speed and both radial pressure and machine efficiency. In contrast, using a 4.8 centimeter pitch feed roller produced a series of inverse relationships between the above variables. Based on the results of this study it is recommended when milling Indica type long grain rice varieties that the cylinder speed of the original machine be increased from 500-600 rmp up to a minimum of 800 rpm to obtain a greater abrasive effect between the grain and the screen. The pitch of the feed screw should be also reduced to decr\ulcornerease the level of internal radial pressure and to obtain higher machine efficiency and increased quality of milled rice with increased cylinder speeds. Further study on the interaction between cylinder speed and feed screw pitch is recommended. 5. An increase in the counter pressure level produced a negative effect On the head rice recovery with an increase in radial pressure, capacity, and machine efficiency over all combinations and at every level of cylinder speed. 6. Head rice recovery rates were conditioned primarily by the pressure inside the whitening chamber. According to the empirical cha racteristics curve developed in this study, the relationships of head rice recovery ($Y_h$) and machine capacity ($Y_c$/TEX>) to internal radial pressure ($X_p$) followed an inverse quadratic function and a linear function respectively: $$Y_h^\Delta=\frac{1}{{1.4383-0.2951X_p^\ast+0.1425X_p^{\ast\ast}}^2} , (R^2=0.98)$$ $$Y_c^\Delta=-305.83+374.37X_p^{\ast\ast}, (R^2=0.88)$$ The correlation between capacity and power consumption per unit of brown rice expressed in the following exponential function: $$Y_c^\Delta=1.63Y_c^{-0.7786^\{\ast\ast}, (R^2=0.94)$$ These relationships indicate that when radial pressure increases above a certain range (1. 6 to 2.0 kg/$cm^2$ based On the results of the experiment) head ricerecovery decrea\ulcornerses in a quadratic relation with a inear increase in capacity but without any decrease in power consump tion per unit of brown rice. On the other hand, if radial pressure is below the range shown above, power consumption increases dramatically with a lin\ulcornerear decrease in capacity but without significant increases in head rice recovery. During the operation of a given whitening machine, the optimum radial pressure range or the correct capacity range should be selected by controlling the feed rate and/or counter-pressure keeping in mind the condition of the grain, particulary the hardness. It was observed that the total number of passes is related to radial pessure level, feed rate and counter-pressure level. The higher theradial pressure the fewer num\ulcornerber of pass required but with decreased head rice recovery. In particular, when using high feed rates, the total number of passes should be increased to more than three by reducing the counter-pressure level to avoid decreaseases in head rice recovery (less than 65 percent head rice recovery on the basis of brown rice) at every cylinder speed. 7. A rapid rise in grain temperature seemed to have a close relationship with the pressure generated inside the whitening chamber and, subsequently with head rice reco\ulcornervery rates. The higher the rate of increase, the lower were the resulting head rice recoveries.

• Journal of Aquaculture
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• v.21 no.4
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• pp.317-324
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• 2008

This study estimated the genetic parameters and breeding values for the growth-related traits of the 1st generation produced in 2005. The heritability of body weight, total length, body height, body shape and condition factor of 180 days old olive flounders Paralichthys olivaceus, the 1st generation of selection, was estimated as 0.564, 0.590, 0.588, 0.306 and 0.332, respectively. And reproductivity of genetic evaluation for crossing superior flounders and inferior ones was tested using the subsequent generation produced in 2006 based on the breeding values of 1st generation. In the least-squares means of body weight and total length for each group of crossing, the values of crossing group between superior flounders ($S{\times}S$) showed $145.6{\pm}1.8\;g$ and $22.4{\pm}0.1\;cm$, respectively. The values of crossing group between superior and inferior flounders ($S{\times}I$) showed $133.2{\pm}2.5\;g$ and $22.1{\pm}0.1\;cm$, respectively. The values of crossing group between inferior flounders ($I{\times}I$) showed $114.0{\pm}2.1\;g$ and $21.08{\pm}0.12\;cm$, respectively. In the results, flounders are determined as appropriate selective breeding fish with the high heritability of flounders in early ages at 180 days old, and the reproductivity of genetic evaluation was also high.

• The Korean Journal of Malacology
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• v.23 no.2
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• pp.217-225
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• 2007

This study was conducted to estimate the general genetic parameters, heritabilities, and genetic and phenotypic correlations on growth-related traits by studying multiple trait animal model in two Korean abalone species, Haliotis discus hannai and H. discus discus. The data was collected from the records of 3,795 individuals produced from 54 sires and 74 dams in Haliotis discus hannai and 399 individuals produced from 7 sires and 7 dams in Haliotis discus discus. The data was evaluated by the Genetics and Breeding Research Center, National Fisheries Research & Development Institute (NFRDI). Genetic parameters were estimated for two abalone species raised in Bukjeju branch, NFRDI, from May 20 to November 1, 2004. The heritability estimates for growth traits of shell length, shell width and body weight obtained from restricted maximum likelihood (REML) were ranging from 0.73 to 0.78 in Haliotis discus hannai, and from 0.87 to 0.89 in H. discus discus. The heritabilities for shell shape and condition factor were ranging from 0.17 to 0.20 in Haliotis discus hannai, and from 0.01 to 0.45 in H. discus discus. Genetic and phenotypic correlations were over than 0.96 between shell parameters and weight in both of abalone subspecies, indicating that breeding for weight gains could successfully be achieved by selecting for shell length.

• Nuclear Medicine and Molecular Imaging
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• v.42 no.1
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• pp.61-69
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• 2008

Purpose: Micro-pinhole SPECT system with conventional multiple-head gamma cameras has the advantage of high magnification factor for imaging of rodents. However, several geometric factors should be calibrated to obtain the SPECT image with good image quality. We developed a simplified geometric calibration method for rotating triple-head pinhole SPECT system and assessed the effects of the calibration using several phantom and rodent imaging studies. Materials and Methods: Trionix Triad XLT9 triple-head SPECT scanner with 1.0 mm pinhole apertures were used for the experiments. Approximately centered point source was scanned to track the angle-dependent positioning errors. The centroid of point source was determined by the center of mass calculation. Axially departed two point sources were scanned to calibrate radius of rotation from pinhole to center of rotation. To verify the improvements by the geometric calibration, we compared the spatial resolution of the reconstructed image of Tc-99m point source with and without the calibration. SPECT image of micro performance phantom with hot rod inserts was acquired and several animal imaging studies were performed. Results: Exact sphere shape of the point source was obtained by applying the calibration and axial resolution was improved. Lesion detectibility and image quality was also much improved by the calibration in the phantom and animal studies. Conclusion: Serious degradation of micro-pinhole SPECT images due to the geometric errors could be corrected using a simplified calibration method using only one or two point sources.

• The Korean Journal of Pesticide Science
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• v.19 no.3
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• pp.335-344
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• 2015

It was conducted to identify all 47 isolates obtained from infected fruits of pepper and boxthorn, and to investigate the mycological characteristics and the response to fungicides. All of 11 isolates from pepper were identified as Colletotrichum acutatum included into A2 group. Among 36 isolates from boxthorn, 14 isolates were identified as C. gloeosporioides, and the others were done as C. acutatum, which were composed as A1 group with 15 isolates and A3 with 7 isolates. After incubating the isolates on PDA at $25^{\circ}C$ for 10 days, the colony color of C. acutatum was greyish white, while that of C. gloeosporioides was orange at center of colony and was gradually turned into an greyish white to the periphery. The rate of conidia showing ellongated ellipsoidal shape with round ends was over 95% in C. acutatum isolated from pepper. However, C. acutatum isolated from boxthorn produced ellongated ellipsoidal conidia with the rate of 75%, and the others were pointed at one or both ends. Regardless of species of Colletotrichum, all isolated used in this study was showed an optimal temperature at $25^{\circ}C$. $EC_{50}$ values of all isolates of Colletotrichum spp. to 2 fungicides as carbendazim and the mixture of carbendazim and diethofencarb was investigated by an agar dilution method. With C. acutatum isolates from pepper belonged to A2 group, the mean of $EC_{50}$ value to carbendazim and the mixture of carbendazim and diethofencarb was 0.68 and $3.16{\mu}g/ml$, respectively. In the case of C. acutatum isolates from boxthorn, which were divided into 2 groups as A1 and A3 group, that to carbendazim was 0.21 at A1 and $0.24{\mu}g/ml$ at A3, while that to the mixture was 1.52 and $3.35{\mu}g/ml$. Isolates of C. gloeosporioides showed the mean of $EC_{50}$ value was $0.12{\mu}g/ml$ to carbendazim and $0.92{\mu}g/ml$ to the mixture. The value of resistant factor was higher in the isolates of C. acutatum obtained in boxthorn than those from pepper.

• Journal of the Korean GEO-environmental Society
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• v.15 no.12
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• pp.117-128
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• 2014

Generally, when constructing a tunnel close to existing structures, the tunnel must be built at a constant distance from the structures that is more than width of tunnel to minimize the impact of interference between an existing structures and new tunnel. Spacing of these closed tunnels should be designed considering soil state, size of tunnel and reinforcement method. Particularly when the ground is soft, a care should be taken with the tunnel plans because the closer the tunnel is to the existing structures, the greater the deformation becomes. As methods of reviewing the effect of cavities on the stability of a tunnel, field measurement, numerical analysis and scaled model test can be considered. In the methods, the scaled model test can reproduce the engineering characteristics of a rock in a field condition and the shape of structures using the scale factor even not all conditions cannot be considered. In this study, when construction of a tunnel close to existing structures, the method and considering factors of the scaled model test were studied to predict the actual tunnel behavior in planning stage. Furthermore, model test results were compared with the numerical analysis results for verifying the proposed model test procedure. Also, practical results were derived to verify the stability of a tunnel vis-a-vis cavities through the scaled model test, which assumed spacing distances of 0.25 D, 0.50 D, and 1.00 D between the cavities and tunnel as well as the network state distribution. The spacing distances of 1.0 D is evaluated as the critical distance by the results of model test and numerical analysis.

• Clinical and Experimental Pediatrics
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• v.49 no.6
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• pp.602-609
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• 2006

Purpose : As the prone position is thought to be an important factor in sudden infant death syndrome(SIDS), this study was conducted to contribute to reducing SIDS by analyzing sleeping positions of infants. Methods : A face-to-face questionnaire was carried out with a total of 170 parents with a baby aged less than 6 months. Results : A total of 170 infants included 95 males(55.9 percent) and 75 females(44.1 percent); their average age was 2.8 months. 45.3 percent slept in a supine position; 34.7 percent in a side or supine position; 7.1 percent in a side position; 4.7 percent in a prone position; 4.1 percent in a non-specific position. Among those in a side position, 59.7 percent were in a supine position in the morning; 19.5 percent were in the side position; 13.4 percent were in a non-specific position; and 4.1 percent were in a prone position. To the question why they slept in a specific position, 34.9 percent answered their baby slept comfortably, and particularly, 42.9 percent in the prone position group answered so. In the supine position group, 21.6 percent answered they had no reason. Both in the prone position and side position groups, 21 percent each answered they were worried about the shape of their baby's head. In the side position group, 22 percent answered that they had a fear of choking due to vomiting. In all sleeping position groups, 8.2 percent and 7.4 percent answered it was because they had a fear of suffocation and they wanted to avoid SIDS, respectively. Conclusion : Many of the parents preferred unstable positions, e.g. the side position and the prone position, which could cause SIDS. Their decision on their baby's sleeping position was not based on exact medical knowledge, but on convenience in taking care of their baby. As it was found that only 6 percent of the subjects were advised from their pediatrist about their baby's sleeping position, moreover, it is necessary to carry out more studies and activities for preventing SIDS caused by improper sleeping positions and educating patents about recommended sleeping positions for their baby.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.62 no.1
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• pp.1-8
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• 2017

We investigated the effect of silicate coating of rice seeds on bakanae disease incidence and the quality of seedlings raised in seedling boxes and transplanted into pots. The silicate-coated rice seed (SCS) was prepared as follows. Naturally infested rice seeds not previously subjected to any fungicidal treatment were dressed with a mixture of 25% silicic acid at pH 11 and 300-mesh zeolite powder at a ratio of 50 g dry seed - 9 mL silicic acid - 25 g zeolite powder. The following nursery conditions were provided : Early sowing, dense seeding in a glass house with mulching overnight and no artificial heating, which were the ideal conditions for determining the effect on the seed. The nursery plants were evaluated for Gibberella. fujikuroi infection or to determine the recovery to normal growth of infected nursery plants in the Wagner pot. Seedlings emerged 2-3 days earlier for the SCS than they did for the non-SCS control, while damping-off and bakanae disease incidence were remarkably reduced. Specifically, bakanae disease incidence in the SCS was limited to only 7.8% for 80 days after sowing, as compared to 91.6% of the non-SCS control. For the 45-days-old SCS nursery seedlings, the fresh weight was increased by 11% and was two times heavier, with only mild damage compared to that observed for non-SCS. Even after transplanting, SCS treatment contributed to a lower incidence of further infections and possibly to recovery of the seedlings to normal growth as compared to that observed in symptomatic plants in the pot. The active pathogenic macro-conidia and micro-conidia were considerably lower in the soil, root, and seedling sheath base of the SCS. In particular, the underdeveloped macro-conidia with straight oblong shape without intact septum were isolated in the SCS ; this phenotype is likely to be at a comparative etiological disadvantage when compared to that of typical active macro-conidia, which are slightly sickle-shaped with 3-7 intact septa. A active intact conidia with high inoculum potential were rarely observed in the tissue of the seedlings treated only in the SCS. We propose that promising result was likely achieved via inhibition of the development of intact pathogenic conidia, in concert with the aerobic, acidic conditions induced by the physiochemical characteristics associated with the air porosity of zeolite, alkalinity of silicate and the seed husk as a carbon source. In addition, the resistance of the healthy plants to pathogenic conidia was also important factor.

• Clinical and Experimental Reproductive Medicine
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• v.35 no.4
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• pp.247-265
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• 2008

Objectives: Many types of liver diseases can damage regenerative potential of mature hepatocytes, hepatic progenitor cells or oval cells. In such cases, a stem cell-based therapy can be an alternative therapeutic option. We examined whether human amnion-derived mesenchymal stem cells (HAM) and human umbilical cord-derived stem cells (HUC) could differentiate into hepatocyte-like cells as therapeutic cells for the liver diseases. Methods: HAM and HUC were isolated from the amnion and umbilical cord of the volunteers after a caesarean section with informed consent. In order to differentiate these cells into hepatocyte-like cells, cells were cultivated in hepatogenic medium using culture plates coated with fibronectin. Effects of hepatocyte growth factor, L-ascorbic acid 2-phosphate, insulin premixture fibroblast growth gactor 4, dimethylsulfoxide, oncostatin M and/or dexamethasone were examined on the hepatic differentiation. After differentiation, the cells were analyzed by RT-PCR, immunocytochemistry, immunoblotting, albumin ELISA, urea assay and periodic acid-schiffs staining. Results: Initial fibroblast-like appearance of HAM and HUC changed to a round shape during culture in the hepatogenic medium. However, in all hepatogenic conditions examined, HUC secreted more amounts of albumin or urea into medium than HAM. Expression of some of hepatocyte-specific genes increased and expression of new genes were observed in HUC following cultivation in hepatogenic medium. Results of immunocytochemistry and immunoblotting analyses demonstrated that HUC secreted albumin into the culture medium. PAS staining further demonstrated that HUC could store glycogen inside of the cells. Conclusions: Both HUC and HAM could differentiate into albumin-secreting, hepatocyte-like cells. Under the same hepatogenic conditions examined, HUC more efficiently differentiated into hepatocyte-like cells compared with the HAM. The results suggest that HUC and HAM could be used as sources of stem cells for the cell-based therapeutics such as in liver diseases.

• Journal of Distribution Science
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• v.9 no.4
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• pp.43-50
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• 2011

Concerning the risk factors of the outbreak of a fire in a traditional market, most of those markets are located in downtown areas or residential areas; thus, although their location may be favorable in terms of marketability, they face a potential risk in that a fire may develop into a large blaze owing to poor environment or the absence of facilities prepared for disaster during a fire. Moreover, as many people are densely poised in the markets, it is very probable that a fire may occur owing to the excessive use of heaters in the winter as well as the reckless use of electric and gas facilities. It seems that traditional markets encounter difficulty being insured against fire, because of their vulnerability and that the vast majority of small-scale sellers are likely to suffer mental anguish and tremendous physical injury in case of a fire. However, most of those sellers in the traditional markets are hand-to-mouth sellers, and they lack awareness of safety concerns and have insufficient experience in safe facility management. As small-scale sellers constitute the majority in the traditional market, the subscription rate of fire insurance in most of the traditional markets is low for the reasons of their needy circumstances and their financial burden. Statistically, the subscription by street vendors is non-existent; therefore, these vendors have a fairly limited access to indemnification after fire damage. Because of these problems, this study's purpose is to identify the current level of insurance subscription by these markets, which are exposed to poor facilities and vulnerability to fire. In order to fix this, it appears that shop owners and consumers will have to band together. For this study, we executed a fire policyholder fact-finding mission at traditional markets with approximately 108 and 981 stores. The research method was executed by an investigation using one-on-one individual interviews using a questionnaire. The contents investigated current insurance subscriptions. The method of analysis looked at the difference of insured amount according to volume size through cross-tabulation of the difference of insured amount by possession form, difference of insured amount by market form, difference of insured amount by category of business, difference of insured amount by market size, etc. Furthermore, the study should be used to propose solutions for problems through theoretical review with the use of a literature research, because the field case study was through interviews with the persons concerned, and the survey of the current insurance subscriptions by traditional market shopkeepers. The traditional market would generally have difficulty affording fire insurance. Fire insurance subscription rates of most of the market proved to be inactive, because of the economic burden of payment. Lack of funds is thought to be the main factor that causes a lack of realization about the necessity of fire insurance. In addition to expensive insurance premiums, sometimes, the companies' valuation of the businesses is lower than their actual valuations, and they do not pay out enough during a claim. The research presents an improvement plan that, when presented at the traditional markets, may strengthen their ability to procure fire insurance through the help of the central government. Researchers connected with the traditional market mainly accomplish the initial research. However, although this research has its limitations, it offers considerable benefits. For future researchers, I would suggest looking at several regions for comparison.