• Korean Journal of Fisheries and Aquatic Sciences
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• v.9 no.2
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• pp.143-150
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• 1976

A trial has been made to find out a new method of calculating the survival rate of a fish Population utilizing the length composition data and the characteristics of the frequency curve of the length which usually is normal distribution curve. In this paper, a stochastic method is introduced and applied to calculate the survival rate of yellow croaker caught by Korean trawlers in the Yellow Sea and the East China Sea in 1971. The results are as follows : Mean of survival rate 0.46089 Variance 0.03073 Standard deviation 0.17529 95 percent confidence interval 0.36040-0.56138.

• Korean Journal Plant Pathology
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• v.1 no.2
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• pp.115-121
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• 1985

To improve methods of screening rice cultivars with field resistance to bacterial leaf blight, testing plant inoculation and neighbor plant inoculation were compared by using 33 rice cultivars. In the testing plant inoculation method, field resistance was evaluated by measuring the leaf areas diseased on the new leaves expanded after the inoculation. Varietal differences in field resistance were recognized more clearly by the testing plant inoculation method than by the neighbor plant inoculation method. Highly significant correlation was observed between the results of the two methods. Some rice cultivars such as, Seomjin, Hangangchal, Taebaeg, Samgang, Milyang 42, Asominori, Java 14, Chugoku 45 and 70X-46 showed remarkable field resistance to bacterial leaf blight. The testing plant inoculation method appeared desirable for screening rice cultivars for the qualitative and field resistance to bacterial leaf blight because of using less labor and less field area than neighbor plant inoculation.

• Journal of the Korean Chemical Society
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• v.28 no.5
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• pp.293-301
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• 1984

-ray fluorescence analysis of $Ta_2O_5$, $Nb_2O_5$ and $ZrO_2$ in tin-slag samples using the simple dilution method was studied. The method is to correct mathematically the calibration curve to the linear line by the dilution. One synthesized standard having similar composition to the sample and tin slag samples were diluted with anhydrous $Li_2B_4O_7$ at the level of 1%, 2% and 3% of the sample content respectively. The diluted samples were fused at $1150^{\circ}C$ for 30 minutes and these glass beads were finely ground and pelletized. Measuring the X-ray intensities with these pellets, analytical results were calculated by the equation derived from J. Scherman's equation for the characteristic X-ray intensity of an element. Analytical results agreed with the reference values obtained by the standard calibration method within allowable error range and were reproducible.

• Korean journal of applied entomology
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• v.13 no.1 s.18
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• pp.41-45
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• 1974

A total of 230 apparently healthy looking potato stocks and 80 potato stocks with symptoms of virus infection were collected from various seed potato farms in Korea and the incidence of potato virus X (PVX), potato virus S (PVS), potato virus M (PVM) and potato virus Y (PVY) was determined by serological microprecipitin tests. Results obtained are as follows. 1. Serological microprecipitin test retreated the presence of PVX, PVS, PVM and PVY in a number of potato stocks grown for the production of seed potatoes in Korea. 2. The occurrence of potato virus M is reported here for the first time in Korea with experimental evidence. 3. Practically $100\%$ (290 stocks, of the apparently healthy looking potato stocks were demonstrated to be infected with both PVX and PVS. The infection percentages of potato stocks with combination of PVX, PVS, PVM and PVY were as follows. PVX+PVS+PVM:$10.3\%$, PVX+PVS+PVY:$4.5\%$, PVX+PVS+PVM+PVY:$1.03\%$ 4. Irish Cobbler and Shimabara, which are the two major potato varieties in Korea, appear to be symptomless carriers of PVX and PVS. However, when these varieties were infected additionally with PVY, usually severe symptoms resulted. 5. Serological microprecipitin technique appears to be highly suitable for early, quick and reliable diagnosis of PVX, PVS PVM and PVY. It is particularly suited for large scale testing of seed potato stocks for the presence of viruses mentioned above.

• Korean Journal of Remote Sensing
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• v.30 no.1
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• pp.149-160
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• 2014

Recently studies on application development and utilization using sensors and devices embedded in smartphones have flourished at home and abroad. This study aimed to analyze the accuracy of the images of smartphone to determine three-dimension position of close objects prior to the development of photogrammetric system applying smartphone and evaluate the feasibility to use. First of all, camera calibration was conducted on autofocus and infinite focus. Regarding camera calibration distortion model with balance system and unbalance system was used for the decision of lens distortion coefficient, the results of calibration on 16 types of projects showed that all cases were in RMS error by less than 1 mm from bundle adjustment. Also in terms of autofocus and infinite focus on S and S2 model, the pattern of distorted curve was almost the same, so it could be judged that change in distortion pattern according to focus mode is very little. The result comparison according to autofocus and infinite focus and the result comparison according to a software used for multi-image processing showed that all cases were in standard deviation less than ${\pm}3$ mm. It is judged that there is little result difference between focus mode and determination of three-dimension position by distortion model. Lastly the checkpoint performance by total station was fixed as most probable value and the checkpoint performance determined by each project was fixed as observed value to calculate statistics on residual of individual methods. The result showed that all projects had relatively large errors in the direction of Y, the direction of object distance compared to the direction of X and Z. Like above, in terms of accuracy for determination of three-dimension position for a close object, the feasibility to use smartphone camera would be enough.

• Korean Journal of Weed Science
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• v.9 no.1
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• pp.69-75
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• 1989

To search germination inhibitors in higher plants, first of all, some experiments containing selection of test weed seeds and effects of solvents and surfactants for bioassay establishment were conducted. Then MeOH-extracts of 45 plants were assayed for germination inhibition activities against Echinochloa crus-galli (L.) Beauv, Digitaria sanguinalis (L.) Scop., Cyperus iria L., Portulaca oleracea L. and Oenothera lamarckiana Ser. seeds. Among them extracts from Rhathiolepis ovata Briat and Picea abies (L.) Karst showed strong inhibitory effect (60-90% inhibition) on the germination of tested weed seeds at 5000 ppm. On the other hand, the extract from Youngia sonchifolia Max stimulated the germination and growth of tested weeds.

• The Journal of Korean Academy of Prosthodontics
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• v.54 no.3
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• pp.218-225
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• 2016

Purpose: The purpose of this study was to evaluate the push-out bond strength of glass-fiber post cemented with different adhesive systems and surface treatments. Materials and methods: 160 tooth samples made from 48 human maxillary single-rooted teeth with similar root length were divided into 4 groups according to the adhesive system (no adhesive, Adper Single Bond 2, Clearfil SE Bond, Clearfil S3). Each group had 4 subgroups according to the post surface treatment methods (no treatment, sandblast, silane, sandblast and silane). Posts (Parapost Fiber White) were cemented with Rely X Unicem. The teeth were sectioned perpendicular to their long axis into 1-mm thick sections. The push-out tests was performed at a speed of 0.5 mm/min. The results were evaluated by 2-way ANOVA, 1-way ANOVA and multiple comparison procedures (Tukey test) (${\alpha}=0.05$). Results: Tukey test showed that the adhesive system significantly influenced the push-out strength. The Clearfil SE Bond group showed the highest value. Post surface treatments showed no significant effect. Conclusion: Bond strength of glass-fiber post cemented with self-adhesive resin cement using Clearfil SE Bond showed significantly higher values compared to other adhesive systems.

• Korean Journal of Soil Science and Fertilizer
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• v.1 no.1
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• pp.117-123
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• 1968

A simplest and best method to find out lime requirement for Korean soils is described. Twenty six top soil samples were collected from various localities and chemical characteristics were dertermined. Three different buffer curve methods were employed as the standard to find out the most reliable test for lime requirement. In addition, the lime requirement test by the Shoemaker's and Woodruff's as well as the O.R.D. kit method were compared with the most reliable buffer curve method. The results may be summarized as follows. 1. The regression equation of the most reliable lime requirement by buffer curve method, y, on percent base saturation of various soils, X, was y=9.69-0.106 X and the negative correlation coefficient r=-0.84 was statistically significant at 5% level. 2. Lime requirement test by the best, buffer curve, method was more well correlated with the sum of exchangeable hydrogen and exchangeable aluminum contents of the soil samples than the exchangeable hydrogen content only. 3. The ordinary buffer curve method for lime requirement is more reasonable than the lime requirement test by the buffer curve prepared after addition of 1 normal potassium chloride or calcium chloride solutions. 4. The lime requirement tests by the most reasonable buffer curve method, X, and by the Woodruff's, the Shoemaker's and O.R.D. kit were compared. The best method for laboratory lime requirement test was the Shoemaker's method and the O.R.D. kit method also was good enough for the field test and these two method are recommended as the unified method of lime requirement test in each soil testing laboratories throughout Korea.

• Culinary science and hospitality research
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• v.15 no.3
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• pp.307-323
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• 2009

This study aims to redefine people's attitudes about well-being trend LOHAS(Lifestyles Of Health And Sustainability) by a systematic research on diners' perspectives about LOHAS and menu-selecting behavior since well-being trend has been a main interest of the media and the food service industry. Also, this study has focused on understanding customers' menu-selecting behavior through a customer interest survey and on customers' interests and verifying factors for healthy food inclination and satisfaction level to give basic information and marketing suggestions for healthful menu. SPSS 12.0 was used for the data analysis, and $x^$-test was carried to make clear the different perspectives about well-being trend LOHAS according to the general characteristics of those polled. Factor analysis was done to menu-selecting behavior. Differences between sampling menu-selecting factors and general characteristics(t-test & ANOVA) were inspected and multiple regression analysis between health inclination and satisfaction level was also conducted. According to the survey, customers' well-being menu selecting behavior showed highly in married women, relatively older people, those with higher general income and higher education. Regression analysis showed that menu-selecting behavior influenced customers' inclination toward health and satisfaction level. Therefore, the food service industry should target those groups and improve its promotional communication strategy with proper menu development and an improved concept.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.29 no.2
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• pp.114-117
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• 1984

To investigate a possibility of screening for the drought resistance of rice varieties in the slope-ridges, this experiment was conducted in Youngnam Crop Experiment Station in 1982. Seeds were vertically seeded on the slope-ridges which has 30 degree slopes from water level at the front to 1 meter height at the back side. A significant positive correlation was observed between the height of slope-ridges and the PF values (Y=2.25 +0.007 X, r =0.990${\ast}\;{\ast}$).The heading date delayed, the culm length was shortened and the yield was decreased in accordance with the height of slope-ridges. Based upon the above results, it was possible to read the drought resistance of the rice varieties tested. Samnambyeo, Milyang 26, Jinjubyeo and Nongrimna 1 were classified as the resistant ones, while Knob 361-1-8-6-149 was susceptible one.