• KOREAN JOURNAL OF CROP SCIENCE
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• v.59 no.4
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• pp.498-504
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• 2014

Potato virus Y (PVY) and potato leafroll virus (PLRV) are among the most damaging potato viruses and prevalent in most potato growing areas. In this study, cryopreservation was used to eradicate PVY and PLRV using two cryogenic methods. Potato shoot tips proliferated in vitro were cryopreserved through droplet-vitrification and encapsulation-vitrification using plant vitrification solution 2 (PVS2; 30% glycerol + 15% dimethyl sulfoxide + 15.0% ethylene glycol + 13.7% sucrose) and modified PVS2. Both cryogenic procedures produced similar rates of survival and regrowth, which were lower than those from shoot tip culture alone. The health status of plantlets regenerated from shoot tip culture alone and cryopreservation was checked by reverse transcription-polymerase chain reaction. The frequency of virus-free plants regenerated directly from highly proliferating shoot tips reached 42.3% and 48.6% for PVY and PLRV, respectively. In comparison, the frequency of PVY and PLRV eradication after cryopreservation was 91.3~99.7% following shoot-tip culture. The highest cryopreserved shoot tip regeneration rate was observed when shoot tips were 1.0~1.5 mm in length, but virus eradication rates were very similar (96.4~99.7%), regardless of shoot tip size. This efficient cryotherapy protocol developed to eliminate viruses can also be used to prepare potato material for safe long-term preservation and the production of virus-free plants.

• Journal of the Korean Society of Physical Medicine
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• v.11 no.1
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• pp.1-9
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• 2016

PURPOSE: This study compared the effectiveness of trunk control exercise performed on an unstable surface with that of general balance exercise on dynamic balance in the patients with chronic stroke. METHODS: The persons of this study were thirty-seven chronic stroke patients were recruited and randomly divided into 2 groups; (1) those who performed trunk control exercise on a foam roll and (2) those who performed general balance exercise. The exercises were performed 5 times a week for 4 weeks. To determine the effectiveness of the 2 types of exercises, we measured dynamic balance at the beginning of the exercises and again after 4 weeks at the completion of exercises program. RESULTS: After 4 weeks of exercise, both the groups showed increased Berg's balance scale and timed-up-and-go test (p<.001) scores. However, Trunk control exercise group was more effective than general balance exercise group was in increasing the Berg's balance scale (p<.01) and timed-up-and-go test (p<.05) scores. CONCLUSION: We suggest that trunk control exercise may be effective in increasing the balance ability of patients with chronic stroke than general balance exercise. Thus, trunk control exercise is important for such patients. Further studies are needed for better understanding of the effectiveness of trunk control exercise in chronic stroke patients.

• Elastomers and Composites
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• v.36 no.4
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• pp.237-245
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• 2001

A study was made on the chemical treatment of silica and silane coupling agents, bistriethox ysilylpropyltetrasulfide(Si 69) and ${\gamma}$-mercaptopropyltrimethoxy silane (MPS) for reinforcement of silica formulation. The effects of chemical treatment method and the most popular two coupling agents were examined. The results clearly indicate that the wet method, coupling agent is combined chemically with the silica prior to mixing, has more dispersion, wetting ability, dynamic properties and stability than the dry method, coupling agent is premixed directly with the silica. The mixing was done using a bench-type kneader having two mixing cam and a two-roll mill, under approximately similar conditions. The physical properties of SBR vulcanizates give rise to marked improvements by addition of Si 69 and MPS in comparison with without silane coupling agents. The optimum amount of Si 69 and MPS was 2 w/w% by experiments in the dry method but was 4 w/w% by EA and TGA analysis in the wet method.

• Journal of the Korean Ceramic Society
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• v.54 no.4
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• pp.292-297
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• 2017

${\beta}-SiAlON$, based on its high fracture toughness, good strength and low abrasion resistance, has been adopted in several industrial fields such as bearings, turbine blades and non-ferrous metal refractories. In general, ${\beta}-SiAlON$ is fabricated by reactive sintering using expensive $Si_3N_4$ and AlN as starting materials. On the other hand, in this study, a cheaper ${\beta}-SiAlON$ starting powder synthesized by SHS was employed to improve price competitiveness compared to that of the reactive sintering process. ${\beta}-SiAlON$ ceramics with various content of the sintering additive $Y_2O_3$ up to 7 wt% were fabricated by conventional pressureless sintering at $1800^{\circ}C$ for 2 to 8 h under $N_2$ pressure of 0.1 MPa. The specimen with 3 wt% $Y_2O_3$ exhibited the best mechanical properties: hardness of 14 GPa, biaxial strength of 830 MPa, fracture toughness of $5MPa{\cdot}m^{1/2}$ and wear rate of about $3{\times}10^{-6}mm^3/N{\cdot}m$.

• Korean Journal of Community Nutrition
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• v.8 no.4
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• pp.547-555
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• 2003

Carbohydrate intake is decreasing along with the reduction of rice consumption among the Korean population. There is an increasing trend of diet-related degenerative diseases with the increased consumption of animal food, and therefore, the increase of animal food intake can be considered as one of causes of the diet-related disease. The objective of this study is to investigate the differences in rice preference and breakfast patterns between the subjects have breakfast regularly and those skipping it. One thousand participants were selected by the stratified sample method from the primary, middle, high school and college, and company workers from 24 cities of Kyeonggi-do. The interviewing procedure was carried by regional home extension workers. Approximately half participants (49.9％) were under the age of 20. Although 86％ of the subjects considered eating breakfast good for health. only 46.4％ of the subjects had breakfast regularly (HB). The rest of them skipped breakfast (SB) more than twice a week. The proportion of subjects hiving no breakfast were 9.3％ of male and 12.2％ of female subjects. The main reason for not having breakfast was due to the limited time. For their breakfast 85％ of the HB ate boiled rice with the side dishes. More subjects in SB (27.8％) preferred the boiled rice with various grains for breakfast than those of HB (21.8％). The subjects in HB (65.5％) preferred boiled plein rice more than those of SB (56.9％). In cases they must have breakfast, 47.7％ of the subjects wanted rice with the side dishes,24.2％ preferred rice ball or rice roll with laver, 10.5％ preferred a rice beverage. More subjects in HB (59.8％) wanted rice with side dishes than those in SB (36.9％). It was found out that selecting rice at the breakfast is still the main choice. Diverse ready-to-eat rice menus have to be developed to increase the rice consumption, specially to increase breakfast eating frequencies of SB through saving time and effort. (Korean J Community Nutrition 8(4) : 547∼555, 2003)

• Korean journal of food and cookery science
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• v.14 no.4
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• pp.367-374
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• 1998

The purpose of this study was to evaluate the microbiological quality of, and to assure the hygienic safety of, the kimbap production in the university foodservice facilities in accordance with the HACCP (Hazard Analysis Critical Control Point) Program. The time-temperature relationship and the microbiological quality (specifically, total plate count and coliform bacteria count) were assessed to find the critical control point (CCP) during each of the production phases. The average of the daily longest duration time of the kimbap at the facilities was 23.4 hours in summer, while 29.6 hours in winter. In the purchasing phase of the raw materials, the microbiological quality of laver, fish paste, carrot and cucumber in summer was not at an acceptable level according to the standard set by the Natick research center, especially the number of TPC and the coliform level of laver was higher than the threshold level. In the refrigerator storage phase, the temperature of the carrot was 7.4$^{\circ}C$. This temperature is far exceeding the standard so that the microbiological counts was increased by the 2 log cycle during the average storage time of 17 hours or more. In the preparation phase, the temperature of the blanching is too low compared to the standard. In the holding phase before serving, its time-temperature relationship was out of the FDA food code standard both in winter and summer. In the sewing phase, the number of microbiological count was higher than the threshold level in summer while that in winter was up to standard. According to the Harrigan and McCance standard, the number of microbiological count of the utensils was higher than the threshold level in summer while that in winter was up to standard.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.5 no.4
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• pp.738-745
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• 2001

In this paper, when the moving object move to the three-dimentional space, the tracking system track the moving object using the fuzzy reasoning. The joint angle el of the manipulator rotate from $0^{\circ}\; to\; 360^{\circ}$ , and the joint angle $\theta_2$rotate from$0^{\circ}\; to\; 360^{\circ}$. The fuzzy singleton is used for fuzzification and the control rule is twenty five and the fuzzy inference method is simplified Mamdani's reasoning and the defuzzification is the SCOG(Simplified Center Of Gravity) of the fuzzy controller To measure of the performance of the designed system, the fuzzy controller is compared with the CTM(Computed Torque Method) controller at the same condition. when the disturbance torque is ON, the both of CTM and fuzzy controller tracked object without error, However, the disturbance torque changed 0.4N, the CTM controller is 10 times greater than fuzzy controller at the sum of absolute error difference. The designed system is showed it's robustness against with disturbance.

• Journal of the Korean Wood Science and Technology
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• v.25 no.4
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• pp.17-21
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• 1997

This study was carried out to develop the manufacturing technique of Korean paper(Hanji) and find out new uses of machine-made Hanji produced on a a large scale by paper machine. Six kinds of Hanji were made and laminated with backpaper by acryl-based or vinyl acetate ethylene-based adhesive. Six kinds of wallpapers were made such as WH 1, WH 2-1, WH 2-2, WH 3-1, WH 3-2 and WH 4. Physical properties and quality test on the wallpapers were examined. Physical strength of the wallpapers was better than each strength of the Hanji and backpaper. It might be a roll of adhesive. And so, Production cost of the Hanji could be brought down if the Hanji was made thin to get strength not enough to cut during lamination of two papers(Hanji and backpaper). Hanji wallpapers of WH 3-1 and WH 4 are lower than a standard in sunlight resistance and WH 1 is in properties of opacity. WH 2-1, WH 2-2 and WH 3-2 were better than Korean standard in some quality tests. WH 2-2 and WH 3-2 were superior to other wallpapers as a whole. About, twenty kinds of wallpapers with surface treatment, are now being produced on the basis of these two types of wallpapers.

• Ocean Systems Engineering
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• v.5 no.3
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• pp.139-160
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• 2015

The global performance of the 5MW OC4 semisubmersible floating wind turbine in random waves was numerically simulated by using the turbine-floater-mooring fully coupled and time-domain dynamic analysis program FAST-CHARM3D. There have been many papers regarding floating offshore wind turbines but the effects of second-order wave-body interactions on their global performance have rarely been studied. The second-order wave forces are actually small compared to the first-order wave forces, but its effect cannot be ignored when the natural frequencies of a floating system are outside the wave-frequency range. In the case of semi-submersible platform, second-order difference-frequency wave-diffraction forces and moments become important since surge/sway and pitch/roll natural frequencies are lower than those of typical incident waves. The computational effort related to the full second-order diffraction calculation is typically very heavy, so in many cases, the simplified approach called Newman's approximation or first-order-wave-force-only are used. However, it needs to be justified against more complete solutions with full QTF (quadratic transfer function), which is a main subject of the present study. The numerically simulated results for the 5MW OC4 semisubmersible floating wind turbine by FAST-CHARM3D are also extensively compared with the DeepCWind model test results by Technip/NREL/UMaine. The predicted motions and mooring tensions for two white-noise input-wave spectra agree well against the measure values. In this paper, the numerical static-offset and free-decay tests are also conducted to verify the system stiffness, damping, and natural frequencies against the experimental results. They also agree well to verify that the dynamic system modeling is correct to the details. The performance of the simplified approaches instead of using the full QTF are also tested.

• Food Science of Animal Resources
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• v.28 no.3
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• pp.333-343
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• 2008

This study was conducted to investigate the compositional properties by different cut of Hanwoo steer beef. 10 cuts [Abjin (short plate), Bosup (top sirloin), Cheggt (striploin), Dngsim (Ioin), Guri (chuck tender), Hongduke (eye of round), Moksim (chuck roll), Sulgit (bottom round), Udoon (top round), Yangji (brisket)] were prepared from 10 Hanwoo steers ($24{\sim}28$ mon old) were used for the experiment. Calorie contents were $2,205{\sim}3713.20\;cal/g$ and loin, striploin, short plate were significantly higher than the other cuts (p<0.05). Loin was highest in cholesterol content, whereas top round and eye of round were lowest among 10 cuts (p<0.05). There were no significant differences in soluble and insoluble collagen contents although chuck tender, chuck roll and bottom round contained significantly higher total collagen and loin and striploin contained significantly lower total collagen contents than the other cuts (p<0.05). The result from the analysis of free amino acids showed that glutamate and alanine contents were $275.99{\sim}536.04\;mg/100g$, $130.63{\sim}175.23\;mg/100g$, respectively and followed by arginine ($7.00{\sim}10.49\;mg/100g$), phenylalanine ($4.70{\sim}13.88\;mg/100g$), and leucine ($5.98{\sim}10.26\;mg/100g$) in 10 cuts. $1^{++}$ grade Hanwoo steer beef had significantly higher IMP (Inosine monophosphate) and inosine in eye of round (30.04% and 6.25%) and top round (33.44% and 6.28%), while hypoxanthine contents were significantly higher in chuck tender than the other cuts (p<0.05). In fatty acid analysis, there were not significantly differences in fatty acid composition among 10 cuts only except for C16:1n7, C20:3n6, and C20:4n6 (p>0.05).