• Journal of the Korean Magnetics Society
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• v.12 no.5
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• pp.189-194
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• 2002

Microstructure and magnetic properties of Sm-Co sintered magnet were investigated with the variation of Zr content and their solution treatment and aging temperatures. The fraction of eutectic structure and the size of eutectic area decreased with increasing x value of cast Sm(C $O_{.688-x}$F $e_{.242}$C $u_{.07}$Z $r_{x}$)$_{7.404}$ alloys. On the other hand, x=0.022 ingot had finer dendritic structure compared to the other alloys. The sintered magnet of Sm(C $O_{.688-x}$F $e_{.242}$C $u_{.07}$Z $r_{x}$)$_{7.404}$ had well defined cell structure which is composed of cell boundary Sm $Co_{5}$ and cell interior S $m_2$Co/ssub 17/ phase. Cell boundary Sm $Co_{5}$ phase has 20nm thickness and its relative angle was 120$^{\circ}$ in x=0.018 and 0.022 alloys. Cell size was decreased with increasing Zr contents. But, x=0.026 alloy has diffuse cell boundary and irregular shape compared to x=0.022 and 0.018 alloys. Maximum value of coercive force and maximum energy Product were obtained from x=0.022 alloys. Optimum solution treatment temperature of Sm(C $O_{.688-x}$F $e_{.242}$C $u_{.07}$Z $r_{x}$)$_{7.404}$ alloy was 1170 $^{\circ}C$ and 1st aging temperature of two step aging process for higher coercivity was 850 $^{\circ}C$.

• Journal of Nutrition and Health
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• v.53 no.3
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• pp.231-243
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• 2020

Purpose: To determine the metabolic influence of the traditional Korean diet (K-diet), which has been regarded as a healthy diet, we investigated the profile of urine organic acids that are intermediates of various types of metabolism including energy metabolism. Methods: Ten women aged 50-60 years were recruited and randomly divided into 2 diet groups, K-diet and control diet, the latter of which is a Westernized Korean diet that is commonly consumed by Koreans nowadays. Before and after the 2-week intervention, 46 urine organic acids were determined using LC/MS/MS, along with clinical parameters. Results: The average concentrations of succinate (4.14 ± 0.84 ㎍/mg creatinine vs. 1.49 ± 0.11, p = 0.0346) and hydroxymethylglutarate (3.67 ± 0.36 ㎍/mg creatinine vs. 2.97 ± 0.29, p = 0.0466), both of which are intermediates of energy metabolism, decreased in the K-diet group after the 2-week intervention, but these were not observed in the control diet group. In particular, the average concentration of succinate in the K-diet group was lower than that in the control group (3.33 ± 0.56 ㎍/mg creatinine vs. 1.49 ± 0.11, p = 0.0284) after 2 weeks. The concentrations of two tryptophan metabolites, 5-hydroxyindolacetate (3.72 ± 0.22 ㎍/mg creatinine vs. 3.14 ± 0.21, p = 0.0183) and indican (76.99 ± 8.35 ㎍/mg creatinine vs. 37.89 ± 10.06, p = 0.0205) also decreased only in the K-diet group. After the 2-week intervention, the concentration of kynurenate, another tryptophan metabolite, was lower in the K-diet group than that in the control diet group (3.96 ± 0.51 ㎍/mg creatinine vs. 2.90 ± 0.22, p = 0.0356). Interestingly, the urine level of kynurenate was positively correlated with BMI (r = 0.61424, p = 0.0003) and total cholesterol (r = 0.46979, p = 0.0088), which decreased only in the K-diet group (239.40 ± 15.14 mg/dL vs. 198.20 ± 13.25, p = 0.0163). Conclusion: The K-diet alters the urinary excretion of organic acids involved in energy metabolism and tryptophan metabolism, suggesting the influence of the K-diet on these types of metabolism. Urine organic acids changed by the K-diet may serve as biomarkers in future studies.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.5
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• pp.613-621
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• 2006

This study was performed to evaluate the storage quality of milk bread added with $\beta$-glucan (10 20 and 30%), which is a functional food material produced from Agrobacterium spp. R259 KCTC 10197BP. During storage ($20^{\circ}C$, 40% relative humidity) the pH of all breads gradually increased, although there were no significant differences in pH of the $\beta$-glucan added milk bread from those of the control. During storage, the moisture content of all groups decreased, however, moisture contents in the $\beta$-glucan added breads were higher than that in the control. Hunter color values ($L^*,\;a^*\;and\;b^*\;value$) of the milk bread added upto 20% $\beta$-glucan were not significantly different, but the lightness increased during storage. Rapid increase of hardness in the milk bread during storage was observed in control, while the hardness of $\beta$-glucan added bread increased slowly. Also, the degree of retrogradation of bread decreased as $\beta$-glucan addition amount increased. Sensory evaluation showed that the score of over-all acceptability of the bread added with 20% $\beta$-glucan was the highest among treated groups until four days of storage. This study confirmed that the addition of $\beta$-glucan to milk bread maintained the moisture content and delayed hardness during storage.

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.81-86
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• 2015

"Youhan" (Hordeum vulgare L.), a new whole-crop barley cultivar, was developed by the breeding team at National Institute of Crop Science, RDA in 2012. Youhan has the growth habit of III, a light green and mid-sized leaf, hooded and lax-type spikes. The cultivar showed 107 cm of culm length, 641 spikes per $m^2$. The heading date of Youhan was May 1, which is one day later than that of the check cultivar "Yuyeon" in upland, and 2 days earlier than that of Yuyeon in paddy field. The maturation time was similar to check cultivar Yuyeon on June 4 in upland and May 31 in paddy field. In terms of winter hardiness and resistance to lodging and disease, Youhan also performed better than the check cultivar. The average forage dry matter (DM) yield in the regional yield trial was approximately 12.6 ton $ha^{-1}$ and 12.0 ton $ha^{-1}$ in upland and paddy field, respectively, which were 6% and 5% higher than that of the check. The yield also showed 7.3% of crude protein, 26.8% of ADF (acid detergent fiber), 47.8% of NDF (neutral detergent fiber), 67.7% of TDN (total digestible nutrients), and a higher grade of silage quality for the whole-crop barley. Fall sowing cropping of Youhan is recommended only in those areas where the average daily minimum-mean temperatures in January are higher than $-8^{\circ}C$, and it should not be cultivated in mountainous areas of Korea.

• Journal of Physiology & Pathology in Korean Medicine
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• v.16 no.2
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• pp.373-379
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• 2002

This paper was the design of aerosol generator for inhalation toxicology study of lead and evaluation with real time monitoring, and applied several engineering methodology to classical aerosol generator to cope with it's disadvantages. According to the testing conditions, source temperature 50℃ and inlet-duct band heater temperature 150℃, aerosol generation results for sodium chloride and lead acetate were as followings: CPM(Count Per Minute) for Sodium chloride that used for the testing material in aerosol generation and inhalation system was decreased in the 2nd and the 3rd hour's serial trials, but CVs(coefficient of variation) were maintained within 10%. CPMs for 5 and 2.5 gram of lead acetate that used for aerosol generation and inhalation exposure of lead showed similar results because of the sedimentation of lead acetate on piezoelectric crystal with time. For that reason, heating and mixing of nebulizing solution will be needed to generate lead aerosol with stable profile and maximum generation efficiency. Fluctuations of 10 and 5 gram lead acetate were low but 2.5gram was high. However, CVs for 10, 5, and 2.5gram lead acetate were within 10%. Considering the theoretical efficiencies for sodium chloride and lead acetate, 5gram sodium chloride and 2.5gram lead acetate were appropriate choice. Aerosol generation characteristics for two materials with 1 hour interval were different with respect to the fluctuation of CPM and the decrease to 10gram in it's material. For that reason, sodium chloride can not be used to estimate the aerosol generation and it's related parts for lead acetate. According to the testing conditions, source temperature 20, 50, 70℃, and inlet-duct band heater temperature 20, 50, 100, 150, 200℃, aerosol generation results for sodium chloride and lead acetate were as followings: Excluding inlet-duct band temperature 200℃, maximum CPM for sodium chloride was manifested in source temperature 70℃ with each inlet-duct band temperature conditions. We suggest that this condition was the optimum in the design of aerosol generator, inhalation system, and the testing. Maximum CPMs for 10, 5, and 2.5gram sodium chloride were from source temperature 70℃ and inlet-duct band temperature 20℃. Excluding inlet-duct band temperature 50, 200℃, maximum CPMs for lead acetate were indicated in source temperature 50℃ with each inlet-duct band temperature conditions. We suggest that this condition was the optimum in the design of aerosol generator, inhalation system, and the testing for lead inhalation study. Source and inlet-duct band temperatures for 10, 5, 2.5gram lead acetate were 50 and 100℃, 50 and 100℃, 50 and 150℃, respectively. In conclusion, considering above 2 paragraphs of results for aerosol generation, 5gram efficiencies for sodium chloride, lead acetate were higher than 2.5gram's. If inlet-duct band temperature was same, aerosol generation was increased with increase of source temperature. To get maximum aerosol generation will be the conditions that set the appropriate inlet-duel band temperature for each materials and increase the source temperature.

• Progress in Medical Physics
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• v.21 no.1
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• pp.86-92
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• 2010

The purpose of this study was to measure curvature contour skin dose using radiochromic film and TLD for a conventional open field. We also attempted to quantify the degradation of skin sparing associated with use of immobilization devices for high energy photon beams and to calculate the skin dose with a help of Monte Carlo (MC) simulation. To simulate head-and-neck and shoulder treatment, a cylindrical solid water phantom 11 cm in diameter was irradiated with 6 MV x-rays using $40{\times}40\;cm^2$ field at 100 cm source axis distance (SAD) to the center of the phantom. Aquaplastic mesh mask was placed on the surface of the cylindrical phantom that mimicked relevant clinical situations. The skin dose profile was obtained by taking measurements from $0^{\circ}$ to $360^{\circ}$ around the circumference of the cylindrical phantom. The skin doses obtained from radiochromic film were found to be 47% of the maximum dose of $D_{max}$ at the $0^{\circ}$ beam entry position and 61% at the $90^{\circ}$ oblique beam position without the mask. Using the mask (1.5 mm), the skin dose received was 59% at $0^{\circ}$ incidence and 78% at $80^{\circ}$ incidence. Skin dose results were also gathered using thin thermoluminescent dosimeters (TLD). With the mask, the skin dose was 66% at $0^{\circ}$ incidence and 80% at $80^{\circ}$ incidence. This method with the mask revealed the similar pattern as film measurement. For the treatments of the head-and-neck and shoulder regions in which immobilization mask was used, skin doses at around tangential angle were nearly the same as the prescription dose. When a sloping skin contour is encountered, skin doses may be abated using thinner and more perforated immoblization devices which should still maintain immoblization.

• Journal of Society of Preventive Korean Medicine
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• v.4 no.2
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• pp.119-141
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• 2000

The current industrial health service is shifting to health improvement business with 1st primary prevention-focused service from secondary and tertiary prevention-focused business, and Oriental medicine can provide such primary prevention-focused service due to the characteristics of its science. In particular, the advanced concept of health improvement can match the science of health care of Oriental medicine. Notably, what is most important in health improvement is our lifestyle, This does not underestimate the socio-environmental factors, which have lessened their importance due to modernism. The approach of Oriental medicine weighs more individuals' lifestyle and health care through self-cultivation. This matches the new model of advanced health business. Oriental medicine is less systemized than Western medicine, but it can provide ample contents that enhance health. If we conceive health-improvement program based on the advantages provided by these two medical systems, this will influence workers to the benefit of their health. Also, health Program needs to define factors that determine individual lives, and to provide information and technologies essential to our lives. The Oriental medicine approach puts more stress on a subject's capabilities than it does on the effect his surrounding environment can have. This needs to be supported theoretically by not only defining the relations between an individual's health state and his lifestyle, but also identifying the degree to which an individual in the industrial work place practices health improvement lifestyle . This is the first step toward initiating health-improvement business . In order to do this, this researcher conducted a survey by taking random samplings from workers, and can draw the following conclusions from it. 1 The sampled group is categorized into', by sender, female 6.6%, and male 93.4%, with males dominant; by marriage status , unmarried 43.9% and married 55.6%, with both similar percentage, and, by age, below 30, 48.4%, between 30 and 39, 27.4%, between 40 and 49, 18.2%, and over 50, 6.0%. The group further is categorized into; by education, middle school or under 1.7%, high school 30.5%, and junior college or higher 65.8% with high school and higher dominant: and by income, below 1.7 million won 24.2%, below 2.4 million won 14.8%, and above 2.4 million 6.3% Still, the group by job is categorized into collegians with 23.9%, office worker with 10.3%, and professionals with 65.8% , and this group does not include workers engaged in production that are needed for this research, but mostly office workers . 2. The subjects selected for this survey show their degree of practicing health-improvement lifestyle at an average of 2.63, health management pattern at 2.64, and health-related awareness at 2.62 The sub-divisions of health-improvement lifestyle show social emotion (2.87), food (2.66). favorite food (2.59), and leisure activities (2.52), in this order for higher points. It further shows health awareness (2.47) and safety awareness (2.40), lower points than those in health management pattern . 3. In the area of using leisure time for health-improvement, males, older people, married, and people with higher income earn higher marks. And, in the area of food management, the older and married earn higher marks . In the area of favorite food management, females, lower-income bracket, and lower-educated show higher degree of practice , while in the area of social emotion management, the older. married, and higher-income bracket show higher marks. In addition, in the area of health awareness, the older, married, and people with higher-income show higher degree of practice. 4. To look at correlation by overall and divisional health-improvement practice degree , this researcher has analyzed the data using Person's correlation coefficient. The lifestyle shows significant correlation with its six sub-divisions, and use of leisure time, food, and health awareness all show significant correlation with their sub-divisions. And. the social emotion and safety awareness show significant correlation with all sub-divisions except favorite food management.

• Korean Journal of Materials Research
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• v.15 no.3
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• pp.161-165
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• 2005

We investigated selective dry etching of GaAs over AlGaAs and InGaP in high density planar inductively coupled $BCl_3/SF_6$ plasmas. The process parameters were ICP source power (0-500 W), RE chuck power (0-30W) and gas composition $(60-100\%\;BCl_3\;in\;BCl_3/SF_6)$. The process results were characterized in terms of etch rate, selectivities of GaAs over AlGaAs and InGaP, surface morphology, surface roughness and residues after etching. $BCl_3/SF_6$ selective etching of GaAs showed quite good results in this study. Selectivities of GaAs $(GaAs:AlGaAs\~36:1,\;GaAs:InGaP\~45:1)$ were superior at $18BCl_3/2SF_6$, 20 W RF chuck power, 300 W ICP source power and 7.5 mTorr. Addition of $(5-15\%)SF_6\;to\;BCl_3$ produced relatively high selectivities of GaAs over AlGaAs and InGaP during etching due to decrease of etch rates of AlGaAs and InGaP (boiling points of etch products: $AlF_3\~1300^{\circ}C,\;InF_3>1200^{\circ}C$ at atmosphere) at the condition. SEM and AFM data showed slightly sloped sidewall and somewhat rough surface$(RMS\~9nm)$. XPS study on the surface of processed GaAs proved a very clean surface after dry etching. It shows that planar inductively coupled $BCl_3/SF_6$ plasmas could be a good candidate for selective dry etching of GaAs over AlGaAs and InGaP.

• Journal of Korean Society of Forest Science
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• v.39 no.1
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• pp.47-56
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• 1978

This study aimed to know difference in freezing resistance among different clonal seedlings or different seed source seedlings of Cryptomeria japonica which has been selected where extreme cold prevails in Korea and Japan. The freezing resistance of three 12-50 year old trees was also measured in the experiment. The freezing resistance was measured in different tissue parts: mainly leaf, cambiam and xylem, at three different collection dates in two different collection places during the winter of 1977-1978. The following results and discussions were made: 1. The clonal difference in freezing resistance of Cryptomeria japonica was $9^{\circ}$ to $15^{\circ}C$ in maximum according to the collection place. However, the clonal difference in freezing resistance was not related to the difference in climatic conditions where the parent tree have been growing. This impiled that the natural selection of cold resistant genes in Cryptomeria japonica has not reached its evolutional equilibrium yet since most of the Cryptomeria forest has been established by artificial regeneration. 2. The difference in freezing resistance among leaf, cambium and xylem was not apparent except that leaf of several clones showed higher freezing resistance than cambium or xylem when they collected at mid-winter. The least freezing resistant tissue part, thought its freezing resistance was not measure in all clones and all temperatures were appeared in the apical buds. The new shoot growth was observed in the next spring with being replaced by its dormant or adventitious bud growth when the apical bud was injured dy cold during winter. 3. The freezing resistance of leaf, cambium and xylem was shown high enough so that freezing resistance Cryptomeria clones in this experiment were supposed to be able to survive in cold winter conditions at the middle part of Korea. However, it was reported that the most susceptible tissue part to winter injury was the basal stem, but of which freezing resistance was not-measured in this experiment. Several silvicultural methods for prevention of Cryptomeria seedlings from cold damage were discussed in literature.

• Progress in Medical Physics
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• v.19 no.2
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• pp.131-138
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• 2008

We evaluated on the calculation accuracy of treatment planning system (TPS) with phantom having convex and concave surface. The TPS is Eclipse (Varian, USA) using both algorithms AAA and PBC for photon dose calculations. PBC algorithms have three corrections of Batho, modified Batho (M-Batho), and equivalent TAR (E-TAR). The field sizes were $10{\times}10\;cm^2$ and $20{\times}20\;cm^2$, and MLC-shaped fields for these fields. We measured doses at three depths 5, 10 and 15cm in phantom of SSD=90cm in the condition of inserted farmer chamber. For given conditions, we have calculated dose with these algorithms and compared them with measured doses. In AAA the calculated doses (dose/MU) were agreed to measured doses within ${\pm}1%$ in flat and convex surface and were under estimated with -1.9% maximum in concave surface. In PBC the calculated doses were over estimated with +1.7% and +4.1% respectively in flat and convex surface and the differences were from -3.1% to +2.1% in concave surface. In comparison of criteria from AAPM and IAEA reports, and statistical analysis for these results, it is found that the AAA's results are in good agreement with measured values and the M-Batho's results are generally good agreed with measured values among PBC algorithms.