• Journal of the Ergonomics Society of Korea
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• v.28 no.2
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• pp.27-34
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• 2009

The purpose of this study was to evaluate aging (young and old), gender (male and female), and handle shape effects on grip force, finger force, and subjective comfort. Four handle shapes of A, D, I, and V were implemented by a multi-finger force measurement (MFFM) system which was developed to measure every finger force with different grip spans. Forty young (20 males and 20 females) and forty old (20 males and 20 females) subjects participated in twelve gripping tasks and rated their comfort for all handles using a 5-point scale. Grip forces were calculating by summation of all four forces of the index, middle, ring and little fingers. Results showed that young males (283.2N) had larger gripping force than old males (235.6N), while young females (151.4N) had lower force than old females (153.6N). Young subjects exerted the largest gripping force with D-shape due to large contribution of the index and middle fingers and the smallest with A-shape; however, old subjects exerted the largest with I-shape and the smallest with V-shape due to small contribution of the ring and little fingers. As expected, the middle finger had the largest finger force and the little finger had the smallest. The fraction of contribution of index and ring fingers to grip force differed among age groups. Interestingly, young subjects provided larger index finger force than ring finger force, whereas old subjects showed that larger ring finger forces than index finger force in the griping tasks. In the relationship between performance and subjective comfort, I-shape exerting the largest grip force had less comfort than D-shape producing the second largest grip force. The findings of this study can provide guidelines on designing hand tool handle to obtain better performance as well as users' comfort.

• The Korean Journal of Ecology
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• v.9 no.1
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• pp.1-7
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• 1986

plastochron index was used as a measure for the nitrate reductase activity (NRA) in Amaranthus retroflexus, Chenopodium album var. centrorubrum and Glycine max. The material plants treated with $NO_3$-N had higher NRA than those treated with ${NH_4}^+$-N. High NRA were found in young tissues which have low PI or LPI in both A. retroflexus and C. album. These results indicated that this enzyme decreased with increasing plastochron index of the extracted tissues. High level of NRA was detected in Glycine max leaves at PI 4.0. On the other hand, there were no significant differences for PI among $NO_3$-treated, ${NH_4}^+$-treated and control in both stems and roots.

• The Journal of the Korean dental association
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• v.14 no.8
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• pp.655-658
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• 1976

The auther had studied dental caries and periodontal disease and other important oral disease in the 806nout patient who came to dental Department in N.M.C. during 1974. The obtained results were as follows ; 1) The dental caries experience rate in the out patient of Dental Departanent in N.M.C. was 8202% and the D.M.F. teeth index was 3.3. 2) The decayed teeth index was 2.18 and the missed teeth index was 0.69 and the filled teeth index was 1065. 3) The periodontal disease rate was 82.8% 4) The oral cancer rate was 2%, mandible and maxillary fracture rate was 4%, and trigeminal neuralgia rate was 0.6%.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.7 no.3
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• pp.120-124
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• 1982

In this paper, the theoretical analysis of lateral guiding in stripe geometry DH Laser Diode is performed. In the analysis, the gain & refractive index variations in active layer are modeled by very analogous methmatical function to their real profile and the two dimensional lateral waveguiding of DH LD have been analyzed by perturbation theory. Finally, the beam width dependence of refractive index variation(n), active layer width(d), and cavity length(L), have been analyzed.

• Korean Journal of Digital Imaging in Medicine
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• v.10 no.1
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• pp.51-58
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• 2008

Obesity which causing many physical and psychological problems is difficult to treatment. The purpose study was investigate relationships between weight, height, body mass index (BMI) and BMD of according to the low, normal, over, obesity, high group. According to obesity index, each group was divided into five proup. Study subjects were man(n=135) and woman(n=145). We checked the BMD of femoral neck and lumbar spine by using dual energy X-ray bone densitometry. Weight was positively correlation with height (p<0.05) by Pearson's correlation matrix. There was a significant difference in BMD of femoral neck and lumbar spine between four(low, normal, over, obesity) groups except for high obesity groul.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.2
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• pp.174-184
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• 2011

The purpose of this study was to evaluate nutrients intakes, glycemic index (GI), glycemic load (GL) according to obesity index in elementary school students. The study subjects included 229 elementary school students (boys=108, girls=121) who were divided into 3 groups consisting of an underweight group (obesity index<-10%, n=58), a normal weight group (10%${\leq}$ obesity index<10%, n=130) and an overweight group (obesity index${\geq}$10%, n=41) by their obesity index. The nutrient and food intakes data obtained by a 3-day food record were analyzed. Daily dietary GI and GL values were calculated from the 3-day food record. The average age of the subjects was 11.9 years. The mean daily energy intake was 2,186.8 kcal in the underweight group, 2,123.5 kcal in the normal weight group, and 2,174.2 kcal in the overweight group. The intakes of calcium and animal calcium per 1,000 kcal in the overweight group were significantly lower than in the underweight and normal weight groups (p<0.01, p<0.05), and fruit, egg and milk intakes in the overweight group were lower than those in the underweight group (p<0.05, p<0.05, p<0.05). The mean daily dietary GI of the underweight, normal weight, and overweight groups were 67.7, 68.4 and 69.5, respectively (p<0.05). The mean daily dietary GL of the underweight, normal weight, and overweight groups were 212.8, 208.1 and 213.3, respectively. The major food source of dietary GI and GL in the three groups was rice. Other major food sources of dietary GI were croquettes, hand-rolled noddle soups, instant noddles, milk, and rice cake. Dietary GI was not significantly correlated with weight, obesity or body mass index, when adjusted for energy, carbohydrate, and dietary fiber. However, GL adjusted to energy, carbohydrate and dietary fiber tended to correlate with obesity index (r=0.126, p=0.059). These results suggest that dietary GI and GL have possibility affecting obesity-related indicators in elementary school students.

• Journal of Applied Biological Chemistry
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• v.65 no.4
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• pp.337-341
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• 2022

In this study, the effect of the combined use of a lipid-soluble n-hexane extract of red ginseng marc (HERGM) and water-soluble arginine, which exhibits anticaries activity, on the growth of Streptococccus mutans was investigated. As a result of checkerboard assay, HERGM and arginine showed a synergistic effect in inhibiting the growth of S. mutans with a fractional inhibitory concentration index of 0.396. Combination treatments of HERGM and arginine resulted in leakage of nucleic acid components and decrease in the viable cell counts of S. mutans, all of which were proportional to the concentration of HERGM. In conclusion, the synergistic effect of HERGM and arginine on the growth inhibition of S. mutans is mainly attributed to HERGM.

• Toxicological Research
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• v.11 no.1
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• pp.127-131
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• 1995

Sequential changes in cell proliferation during the development of epitherial kidney tumors induced in rats were investigated by autoradiographic determination of the $^3H$-thymidine-labeling index. Renal cell tumors were induced in male Sprague-Dawley rats by oral administration of N-nitrosomorpholine at the concentration of 120 mg/l in the drinking water for 7 weeks. At different times between 12 and 34 weeks after withdrawal of the carcinogen (stop model) animals were sacrificed. According to cytological criteria, neoplastic lesions were classified into clear cell, acidophilic cell, basophilic cell and oncocytic tumors. The labeling index was found to be increased in all types of preneoplastic tubules as compared to their corresponding original tubules. A much stronger elevation of cell proliferation was ocurred during the development of renal cell tumors from preneoplastic tubules. Of four tumor types, acidophilic cell tumor showed the highest labeling index while oncocytoma exhibited the lowest proliferative activity. These findings are in good accordance with the clinical observations that acidophilic cell tumors have a worse prognosis than oncocytoma. The data presented in this study suggest that the individual proliferation rates may be an objective biological marker of kidney tumor aggressiveness.

• Journal of Advanced Marine Engineering and Technology
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• v.6 no.2
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• pp.21-41
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• 1982

Viscosity, especially characteristic among various properties of visco-elastic fluids such as high polymer solutions, is affected mainly by temperature and concentration. Hence, it is important for fluid engineering to express, by some equations, how the fluid characteristics vary with the change of temperature and concentration and to analyze them to obtain consistent viscous characteristics. High polymer solutions, synthetic products of modern chemical industry, suggest many interesting investigations because they are typical visco-elastic materials. Experimentation was made to derive some useful fluid characteristic equations of SEPARAN-NP10 (polyacylamide) expressed by n (flow behavior index) and K' (consistency index) when it is given temperature and concentration variation. To measure viscosity, capillary viscometer was adopted and the range of experimentation is 0-2,000 P.P.M. in concentration and 15-55 .deg.C in temperature. The experimental results are summarized as follows: The flow behavior index n 1) has nearly constant results irrespective of temperature variation at same conentration and the results are shown in (Table. 4-4-3) 2) has following equation, regardless of temperature, for the variation of concentration. n=-1.0765*10$^{-4}$ P+0.9915 (P:P.P.M.) The consistency index K' 1) has different results for the variation of temperature at same concentration and the results are given in (Table.4-7-2) 2) has following equation for the variation of concentration at same temperature. log 10$^{4}$K' =6.4785*10$^{-4}$ P-1.0529 (P:P.P.M)

• Journal of Ecology and Environment
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• v.46 no.4
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• pp.324-333
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• 2022

Background: The Korean scarlet dwarf, Nannophya koreana Bae (Odonata: Libellulidae), is anendangered dragonfly with an increasing risk of extinction owing to rapid climate changes and human activities. To prevent extinction, the N. koreana population and their habitat should be protected. Therefore, suitable habitat evaluation is important to build the N. koreana restoration project. The habitat suitability index model (HSI) has been widely used for habitat evaluation in diverse organisms. Results: To build a suitable HSI model for N. koreana, 16 factors were examined by seven experienced researchers. A field survey for N. koreana observed sites and spatial analysis were conducted to improve the model. Five factors were finally selected by this procedure (crown density, open water surface, water depth, pioneer plant cover, and type of water source). Finally, the N. koreana HSI model was generated with the five adjusted factors based on interview, field survey, and spatial analysis. This model was validated by a current N. koreana habitat in 2021. With this model, 46 sites in Uljin-gun, Korea, were surveyed for N. koreana habitats; five sites were identified as core habitats and seven as potential core habitats. Conclusions: This model will serve as a strong foundation for the N. koreana restoration project and as a reference for future studies on N. koreana and other endangered insect populations. Further analysis and long-term data will improve the efficacy of this model and restore endangered wildlife.