• Korean Journal of Soil Science and Fertilizer
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• v.33 no.6
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• pp.405-415
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• 2000

To determine application rate of elemental sulfur to adjust pH of alkaline soil, buffer curve method was investigated. The elemental sulfur required to control pH 8.3 to pH 6.3 by buffer curve calculation was treated in two soils of silty loam and sandy loam, and the sulfur-mixed soils were moistened with 50% of water holding capacity during incubation of 6 weeks at $30^{\circ}C$. Soil pH was lowered with incubation and reached to target point after 4 weeks of incubation, and elemental sulfur was oxidised entirely to sulfate. This means that buffer curve has the accuracy to determine sulfur application rate in alkaline soil. However it is estimated that application rate of sulfur should be carefully determined in the field scale. Excess application of elemental sulfur resulted in extremely low soil pH and caused the hinderance of lettuce growth by nutritional imbalance and ion toxicity. To simplify the determination procedure of sulfur requirement, buffer curve method by addition of 0.1N-HCl solution as unit of mL was developed, it was compared with theroutine methods which diluted $H_2SO_4$ solution and $Ca(OH)_2$ are added as cmolc per kg soil to adjust each pH step. Buffer capacities, cmolc kg $soil^{-1}$ $pH^{-1}$, calculated from two buffer curves were not significantly different. The result indicates that buffer curve method by 0.1N-HCl can be used to adjust high pH of alkaline soil.

• Korean Journal of Soil Science and Fertilizer
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• v.30 no.3
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• pp.248-256
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• 1997

In order to establish a optimum level and proper method of fly ash application for soybean cultivation, the successive three years experiment was conducted in the field applied with four application levels of fly ash, 0, 30, 60, 90 MT/ha during the 1991 to 1993. Influence of successive application and residue of fly ash in soil on soybean growth and yield was discussed. Fly ash application had a favorable effect on soybean growth, however over application such as 90 MT/ha caused to turn the color into the brown of young leaf edge and eventually to have necrosis on the leaf. This symptom was prominent under the application of bituminous coal fly ash. In the 1st year cultivation of soybean, the highest yield was obtained at application level of 30 MT/ha. In the 2nd year, application of anthracite fly ash showed the highest yield at 60 MT/ha for successive application and at 90 MT/ha for the 1st year application followed by the 2nd year residue. Application of bituminous coal fly ash showed the highest yield at 60 MT/ha for the both successive application and residue. In the 3rd year, successive application of the both fly ash was given the highest yield at 30 MT/ha, respectively indicating the decrease of yield with increasing level of application. In case of residue plot, the highest yield by the application of anthracite fly ash was made at 90 MT/ha for the 1st year application followed by 2 years residue and at 60 MT/ha for the 1st and 2nd year application followed by the 3rd year residue. But in the residue plot of bituminous coal fly ash, yield was highest at 30 MT/ha showing the decrease of yield with increasing level of residue. Enhancement in growth and yield of soybean by application of fly ash was due to the fact that fly ash contained some plant nutrients such as phosphorus, silicon, and boron etc. and reformed soil pH that caused to increase availability of nutrients in soil.

• Korean journal of food and cookery science
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• v.23 no.5
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• pp.650-663
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• 2007

The purpose of this study was to identify the sanitation management items of school foodservice suppliers that require improvement, by assessing their sanitation practices with food commodities. Our field assessment was performed using a total of 20 vendors supplying agricultural products, meat products, seafoods and processed products; all were located in the Seoul and Gyeonggi areas. The assessment tool for sanitation management was composed of 93 checklist items and was used to evaluate seven different categories; the facility and environment, management of the facility and equipment, food materials management, process control, water management, personal hygiene management, and laboratory instrument management. A score of two was given for "satisfactory", one for "fair", and zero for "unsatisfactory". The overall average supplier score was 1.7/2.0 (85.8%). The score of the seafood vendors was highest at 1.9 (95.4%), while the lowest score of 1.3 (65.7%) occurred with the processed product suppliers. Among the sanitation management categories, water management was scored at 2.0, while inspection management was lowest at 1.4. The subcategories indicating needed improvements for the processed product suppliers were raw materials, storage, transport and recall. For the agricultural product suppliers it was preparation management. furthermore, one item within the laboratory instrument management category was unsatisfactory for both the agricultural and processed product suppliers. In conclusion, these results can be used to develop sanitation management procedures for suppliers, as well as by administration agencies to evaluate and guide those suppliers.

• Journal of Korean Ophthalmic Optics Society
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• v.19 no.4
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• pp.551-555
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• 2014

Purpose: This study is to investigate if the improvement of visual sensory (VS) by amblyopia treatment affects the ocular functions in refractive errors, accommodative errors and phoria at distance and near. Methods: 10 subjects (17 eyes, mean age of $10.7{\pm}2.9$ years) who treated amblyopia completely, were participated for this study. Refractive errors, accommodative errors, and distance and near phoria were compared between before and after treatments of amblyopia. Refractive errors and accommodative errors at 40 cm were measured using openfield auto-refractor (NVision-5001, Shin Nippon, Japan) and using monocular estimated method (MEM) respectively. Phoria was determined at 3 m for distance and at 40 cm for near using Howell phoria card, cover test or Maddox rod. Results: Mean corrected visual acuity (CVA) significantly increased from $0.46{\pm}0.11$ (decimal notation) for before amblyopia treatment to a level of $1.03{\pm}0.13$ for after amblyopia treatment (p < 0.001). For spherical refractive error, hyperopia significantly decreased from $+2.29{\pm}0.86D$ to a level of $+1.1{\pm}2.38D$ (p < 0.05) but astigmatism did not significantly change; $-1.80{\pm}1.41D$ for before treatment and $-1.65{\pm}1.30D$D for after treatment (p > 0.05). Accommodative error significantly decreased from accommodative lag of $+1.1{\pm}0.75D$ to a level of $+0.5{\pm}0.59D$ (accommodative lag) (p < 0.05). Distance phoria significantly changed from eso $2.9{\pm}6.17PD$ (prism diopters) to a level of eso $0.2{\pm}3.49PD$ (p < 0.05), and near phoria also significantly changed from eso $0.4{\pm}2.32PD$ to level of exo $2{\pm}4.9PD$ (p < 0.05). There was a high correlation (r = 0.88, p < 0.001) between improvement of visual acuity and decrease of accommodative lag. Conclusions: Hyperopic refractive error decreased with improvement of CVA or VS by amblyopia treatment. And the improvement of VS by amblyopia treatment also improved accommodative error, and changed phoria coupled with accommodation.

• The korean journal of orthodontics
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• v.38 no.1
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• pp.52-59
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• 2008

Objective: This study analyzed the morphologic changes of the fourth cervical vertebra body to determine the skeletal age of orthodontic patients during growth. Methods: Eighty-one female patients aged from 11 to 14 who had cephalograms taken on the same day were examined. The subjects were divided into three groups depending on the depth of the concavity of the lower border of the fourth cervical vertebra (Group A: less than 1.05 mm, Group B: 1.05 - 2.07 mm, Group C: greater than 2.07 mm). Menarcheal timing, SMI stage, length, width and ratio of length and width of the fourth cervical vertebra body were analyzed and the following results were obtained. Results: The average SMI stage of group A, B and C were $5.67{\pm}2.57,\;8.73{\pm}2.41,\;and\;10.00{\pm}1.47$, respectively. Length, width, ratio of length and width, and SMI stage were greater in group B than group A and in group C than group B. Mean menarcheal timing was $11.64{\pm}0.92$ years. Concavity depth, length, width, ratio of length and width showed a significant positive correlation with SMI stage, especially with the concavity depth. Conclusion: The results of this study propose a simple method for determining the timing of orthopedic treatment by measuring the concavity depth of the fourth cervical vertebra on the cephalogram.

• Journal of dental hygiene science
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• v.10 no.4
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• pp.241-250
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• 2010

The purpose of this study, which was processed from March $22^{nd}$ to April $9^{th}$ of 2010, was to figure out recognition, well-formed instructions, and Practical application about dental hygiene devices based on the dental health characteristics of 350 adults who dwell in Busan and Gyeongnam regions. Also, this study recommended the adults to use dental hygiene devices and provided such devices to help individuals take care of their dental health at home. The collected data was statistically processed with a statistics SPSS (Statistical Packages for Social Science 14.0. SPSS Inc. USA) program. First of all, in order to demonstrate the characteristics of the sample population statistics and that of the descriptive data, frequency analysis was performed and to find out the relationship between variations of the dental health, Chi-squared test through Crosstabs was operated. According to the study, recognition and Practical application of dental hygiene devices were very low. Therefore, public announcement about necessity and effectiveness of such devices should be reinforced nationwide and instructions on choosing the right device and using of the dental hygiene devices based on patients' conditions by dental hygienic human efforts gathered from dental health organization should be carried out.

• The korean journal of orthodontics
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• v.27 no.1
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• pp.105-117
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• 1997

This investigation examined the effect of lateral shift of mandible from functional occlusal interference on the growth of mandible and the growth pattern of mandible shown after the removal of occlusal interference. The followings were performed with the results below : the changes in mandible and condylar cartilage were studied in the experimental group with upper right, lower left incisors cut for 2 and 4 weeks- an 4-week-old rats and the experimental group which had cut for 4 weeks and suspended for 2 weeks. 1. In the 2-week experimental group, the left mandibular length, condylar length, mandibular height and condylar area seemed smaller than those on the right and the normal group ; the right mandibular length and condylar area were smaller than the normal group. 2. In the 4-week experimental group, left condylar area was smaller than the right, but due to the quick changes in adaptability of left mandible, right and left mandibular lengths were similar. compared with the normal group, however, mandibular length and condylar area still remained small. 3. In the 6-week experimental group, the left and the right appeared similar with the mandibular length remaining still shorter than the normal group. 4. In the sagittal plane, the proliferation of the cartilage layers of the left condylar cartilage of the 2-week group appeared to have general repression compared with the right and the normal group. The right side also showed repressed growth compared with the normal group. In the 4 and 6-week groups, however, it was similar to the normal group. 5. In condylar cartilage volume, no significant difference was noted in the comparisions of left and right of the experimental group, nor in the comparison of the same sides of experimental wand normal groups. Based on the above, in case of contralateral incisal cutting in rats, it was observed that the growth of mandible and condyle of the cutting side was repressed, at the same time, the quick adaptability led to similar changes of growth in left and right mandibles. But judging from the similar phenomena throughout the whole experimental period in the changes of condylar cartilage volume in the experimental, right and left, and normal groups, the general overall growth of condylar cartilage was found unrepressed. It was also recognized that the growth of condylar cartilage can take in various directions.

• Journal of Chest Surgery
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• v.31 no.9
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• pp.861-866
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• 1998

Background: Pulmonary atresia (PA) with ventricular septal defect has various morphology of pulmonary arteries and pulmonary blood flow sources, so pulmonary arterial hypoplasia and arborization abnormality make this anomaly difficult to manage surgically. In cases associated with juxtaductal stenosis, we evaluated the change of the pulmonary arterial and juxtaductal stenotic site after shunt operations, and would like to find useful information in surgical planning and methodology of these patients. Material and Method: Among 59 cases diagnosed as PA with ventricular septal defect associated with juxtaductal stenosis, 29 cases who had cardiac catheterization before and after shunt operation were selected from July, 1991 to July, 1996. In 10 cases of right shunt operation(Group I) and 19 cases of left shunt operation (Group II), the diameters of the descending aorta, both pulmonary arteries, and the juxtaductal stenosis site were measured before and after the shunt operation. Result: In both Group I and II, the pre- and postoperative ratio of diameters of the ipsilateral pulmonary artery to the descending aorta was from 0.78${\pm}$0.31 units to 1.01${\pm}$0.26 units and from 0.67${\pm}$0.18 units to 0.84${\pm}$0.27 units respectively, showing a signigicant increase. The contralateral pulmonary artery index was increased from 0.92${\pm}$0.28 units to 1.05${\pm}$0.15 units and from 0.94${\pm}$0.27 units to 1.08${\pm}$0.37 units respectively, but could not be confirmed statistically. In both groups, the change of juxtaductal stenosis showed an aggravating tendency but of no statistical significance from 0.43${\pm}$0.27 units to 0.39${\pm}$0.25 units and from 0.32${\pm}$0.10 units to 0.30${\pm}$0.16 units respectively, and we experienced 2 total obstruction in Group II. Because the increased pulmonary blood flow by shunt operation has a favorable effect to the pulmonary arterial growth, the shunt operation is a recommended treatment in patients with hypoplastic pulmonary arteries. But in PA with ventricular septal defects, the change of juxtaductal stenosis is very important. In conclusion, the growth of ipsilateral (shunt site) pulmonary artery was promoted by shunt operation, but there is a tendency for the juxtaductal stenosis to be aggravated. And we experienced 2 total obstruction in Group II. Conclusion: Thus, in cases operated with shunt method, much careful postoperative follow up study including angiographic evaluation is needed, and after the shunt operation on the side of pulmonary artery associated with juxtaductal stenosis, early precise planning for total correction is recommended.

• Journal of The Korean Ophthalmological Society
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• v.59 no.11
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• pp.1009-1016
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• 2018

Purpose: To assess the effect on axial elongation and associated factors between spectacles and of orthokeratology lens (OK) wearing in children with mild to moderate myopia. Methods: A total of one hundred subjects, ranging in age from 6 to 13 years, and with mild to moderate myopia no more than -4.50 diopters in spherical equivalent, visited our clinic from 2013 to 2015. The OK group (75 eyes) and the spectacles group (64 eyes) were compared and analyzed on the axial elongation and associated factors. Results: In the OK group, axial length was elongated in 1 year period with a mean increase of $0.24{\pm}0.29mm$. In spectacles group, axial length was elongated in 1 year period with a mean increase of $0.42{\pm}0.20mm$. The statistically significant suppression of axial elongation was observed in OK group compared to the spectacles group (Mann-Whitney U test, p < 0.05). For OK group, the age of starting OK (Pearson's correlation, r = -0.481, p < 0.05) was the only influencing factor on axial elongation, which had negative correlation with axial elongation. In spectacles group, the age of starting spectacles had negative correlation with axial elongation (Pearson's correlation, r = -0.462, p < 0.05) and baseline spherical equivalent, spherical diopter, cylindrical diopter from manifest refraction had positive correlation with axial elongation. Comparison of axial elongation in orthokeratology lens group and spectacles group by age groups (6 to 9 years [28 eyes], 9 to 13 years [47 eyes]), 9 to 13 years of orthokeratology lens group had the stronger suppression of axial elongation (Mann-Whitney U test, p < 0.05). Conclusions: The OK effectively suppresses axial elongation compared to the spectacles. Although the patients are in age from 9 to 13 years, the axial elongation was effectively suppressed.

• Korean Journal of Cognitive Science
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• v.17 no.2
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• pp.75-102
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• 2006

Three experiments were conducted using a verification task to examine good and poor readers' generation of causal inferences(with because sentences) and contrastive inferences(with although sentences). The unfamiliar, critical verification statement was either explicitly mentioned or was implied. In Experiment 1, both good and poor readers responded accurately to the critical statement, suggesting that both groups had the linguistic knowledge necessary to the required inferences. Differences were found, however, in the groups' verification latencies. Poor, but not good, readers responded faster to explicit than to implicit verification statements for both because and although sentences. In Experiment 2, poor readers were induced to generate causal inferences for the because experimental sentences by including fillers that were apparently counterfactual unless a causal inference was made. In Experiment 3, poor readers were induced to generate contrastive inferences for the although sentences by including fillers that could only be resolved by making a contrastive inference. Verification latencies for the critical statements showed that poor readers made causal inferences in Experiment 2 and contrastive inferences in Experiment 3 doting comprehension. These results were discussed in terms of context effect: Specific encoding operations performed on anomaly backgrounded in another passage would form part of the context that guides the ongoing activity in processing potentially relevant subsequent text.