• Korean Journal of Remote Sensing
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• v.19 no.5
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• pp.393-402
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• 2003

In times of the civil uses of commercialized high-resolution satellite imagery, applications of remote sensing have been widely extended to the new fields or the problem solving beyond traditional application domains. Transportation application of this sensor data, related to the automatic or semiautomatic road extraction, is regarded as one of the important issues in uses of remote sensing imagery. Related to these trends, this study focuses on automatic road extraction using Gradient Direction Profile Algorithm (GDPA) scheme, with IKONOS panchromatic imagery having 1 meter resolution. For this, the GDPA scheme and its main modules were reviewed with processing steps and implemented as a prototype software. Using the extracted bi-level image and ground truth coming from actual GIS layer, overall accuracy evaluation and ranking error-assessment were performed. As the processed results, road information can be automatically extracted; by the way, it is pointed out that some user-defined variables should be carefully determined in using high-resolution satellite imagery in the dense or low contrast areas. While, the GDPA method needs additional processing, because direct results using this method do not produce high overall accuracy or ranking value. The main advantage of the GDPA scheme on road features extraction can be noted as its performance and further applicability. This experiment study can be extended into practical application fields related to remote sensing.

• The Journal of Korean Physical Therapy
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• v.31 no.4
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• pp.236-241
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• 2019

Purpose: This study examined the effects of aquatic proprioceptive neuromuscular facilitation pattern exercise on the balance, gait ability, and depression in patients with chronic stroke. Methods: Thirty patients with chronic stroke were assigned randomly to an experimental (n=15) or control (n=15) group. The experimental group performed aquatic proprioceptive neuromuscular facilitation pattern exercise. The control group performed ground proprioceptive neuromuscular facilitation pattern exercise. Training was conducted once a day for 30 minutes, five days per week for six weeks. The balance ability was measured using the Berg balance scale. The gait ability was measured using the 10 Meter walk test. Depression was measured using the Beck depression inventory. Results: As a result of a comparison within groups, the experimental and control group showed a significant difference for balance, gait ability, and depression after the experiment (p<0.05). In a comparison between the two groups, the experimental group, in which aquatic proprioceptive neuromuscular facilitation pattern exercise was applied, showed more significant changes in balance, gait ability, and depression than the control group (p<0.05). Conclusion: Based on these results, aquatic proprioceptive neuromuscular facilitation pattern exercise effectively improved the balance, gait ability and depression in patients with chronic stroke.

• Journal of Korean Physical Therapy Science
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• v.29 no.2
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• pp.20-27
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• 2022

Background: The purpose of the present study was to determine whether balance training combined with light touch improves the postural sway and gait speed in stroke patients. Design: Randomized Controlled Trial Study Methods: The current study included 40 stroke patients, who were randomly divided into two groups: the balance training with light touch (LT) group (n=20) and the balance training with heavy touch (HT) group (n=20). Both groups performed balance training on a stable and unstable ground. Additionally, the LT group provided light touch stimulation, and the HT group provided heavy touch stimulation. All the participants underwent 20 sessions of STS training (thirty minutes, five days per week for four weeks). In this study, postural sway was measured using a force platform, and walking speed was measured using a 10 meter walk test. Results: The improvements in postural sway and gait speed were observed to be significantly greater in the LT group, compared to the HT group (p<0.05). Conclusion: The results of the current study imply that balance training combined with light touch is a beneficial and effective therapeutic modality that can be employed to improve the postural sway and gait speed in stroke patients.

• Journal of Korean Tunnelling and Underground Space Association
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• v.18 no.4
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• pp.355-364
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• 2016

Recently, a 3,250 meter-long tunnel was constructed beneath the sea bed formed of composite sedimentary soils to transport reusable waste heat gas of industrial complex in the west coast of Korea. Some risks such as machine settlement always exist due to the uncertainties of geological and construction factors during the subsea shield TBM tunnelling. In this construction site, the deviation of tunnel alignment caused by shield TBM settlement was occurred during excavation. It was examined that the lack of bearing capacity of soft clay was a main cause. This paper evaluates the risk of shield TBM tunnelling considering the ground conditions. Correlation between machine settlement and its advance rate was evaluated through the analytical equation in which bearing capacity is considered and a 3-D numerical analysis which can simulate the TBM advance condition (in other words, the dynamic condition). It was found out that a shield TBM could settle due to the insufficient bearing capacity of soft clay layers. In order to prevent such the problem, the best advance rate proper to the ground characteristics is needed to be applied. In the ground conditions of the section of interest, it was turned out that if the shield TBM advance rate was maintained between 35 mm/min and 40 mm/min, the machine settlement could be avoided.

• Magazine of the Korean Society of Agricultural Engineers
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• v.17 no.4
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• pp.3897-3920
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• 1975

Since the most of Korean dairy and cattle raising farms are too small to introduce western mechanized farming, it is necessary to develope small size equipments. This study has been carried to develop a rotary mower as on attachment of 8 to 10 horse powertiller which is widely spread in rural area. It will not ony be helpfull for the farmers to harvesting hay grass but also desirable to increase the power tiller utility. The protto type rotary mower designed through the fundamental investigations, has been modified and improved through the field trials, and a series of field tests has been carried to investigate its performance and economic feasibility comparing with existing vailable harvesting equipments. The results are as follows; 1. To increase the stability, two guide wheels are attached to both side of the protto type rotary mower. 2. To prevent the clinging of tall grasses, the vertical driving shafts are covered with cylindrical protectors. 3. The cutting height is adjustable in 8 steps from 2.5 to 20 centimeters by changing the length of guide wheel legs. 4. The practical Critical cutting speed were always higher than theoretical value in both case of single cutting blade and three when the cutting depth was 25 millimeter. 5. The peripheral speed of cutting blade was varied in response to the change of engine speed, mean while the peripheral speed was adequate as it was changhed from 25 to 35 meter per second when the power tiller is operated in proper working ground speed. 6. The time requirement to harvest 10 a were 88.7, 54.6 and 41.4 minutes for the first, second and third stage of ground speed respectively, and because of the difficulty of delivery, it was observed that operating with fourth stage of ground speed was not recomanendable when the grass height is taller than 90 centimeters. 7. The performance of rotary mower were 1.1-1.7, 1.4-4.0, 3.8-11.8 and 7.4-22.0 times of reciprocating mower, portable disc type cutter, hay scythe and ordinary sickle respectively. 8. When the slope exceeds, 20 degree the downward harvesting operation was impossible because of the excessive front end weight, while less than 5 degree of land slope did not effect in field operation. 9. Increased traveling spee caused higher cutting height and slight cutting failure, but seems not to effect to the gross yield, and the efficiency of cutting width were from 83 to 94 precent. 10. Tn rank of economy were rotary mower (3,2 stage operation), reciprocating mower, hay scythe, portable disc type cutter and sickle in order when the annul operation exdeeds 100 hours. From the above results, it is convinced that the protto type rotary mower is good enough to the livestock farmers as a hay harvesting equipment because of its economy, hardiness in operating and its out standing performance and hopefully it will contribute to the extension of Korean livestock farming.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.36 no.6
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• pp.1161-1167
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• 2016

In this study, an attempt was made to conduct a case study on the development of ground expansive displacement due to lack of bearing capacity of original ground in spite of applying reinforcement treatments that intended to enhance the stability of big size high-speed rail tunnel in large fault zone. For the purpose of this, in-situ measurements made in the middle of excavation stage were analyzed in order to characterize ground responses and numerical analysis was performed to evaluate the effectiveness of reinforcement technique such as elephant foot method applied for this site via comparing with field monitoring measurements. In addition, further numerical studies were carried out to investigate the influence of leg pile installation angle and length, which is one of types of elephant foot method. The results revealed that the optimum condition for the leg pile installation is to maintain 45 degree of installation angle along with 6 meter of embedment depth.

• Journal of Korean Society of Forest Science
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• v.21 no.1
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• pp.35-38
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• 1974

In order to investigate reproductive capacity of genus Lespedeza 5 spp,; L. bicolor, L. maximowiczii, L. japonica var. intermedia, L. angustifolioides, and L, cyrtobotrya, their hights, diameter at the ground level, and the number of sprouts were compared with each other at the end of October during investigating years from 1970 to 1972. For measuring of invested items, 6 stocks which the one-year aged stem were cut above ground were randomly planted per square meter with six replications at the spring of 1970. After hights, diameter, and the number of sprouts were measured at the end of October every year, the stem were cut above ground at the end of November from 1970 to 1972. The results are as follows: 1. The reproductive of the stems showed statistically significant differences at 1% level by species and stock ages. L. bicolor showed the best reproductive capacity of them. 2. The sprouting ability was revealed that L. maximowiczii showed the best of them. 3. The reproductive capacity of stem, diameter, and number of sprouts increased with aging of stock up to 4 years on the investigated 5 species.

• Journal of Korean Society of Forest Science
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• v.35 no.1
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• pp.15-18
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• 1977

In order to investigate reproductive capacity of genus Lespedeza 5 spp.; L. bicolor, L. maximowiczii, L. japonica var. intermedia, L. angustifolioides, and L. cyrtobotrya, their hights, diameter at the ground level, and the number of sprouts were compared with each other at the end of October during investigating years from 1970 to 1976. For measuring of invested items, 6 stocks which the one-year aged stem were cut above ground were randomly planted per square meter with six replications at the spring of 1970. After hights, diameter, and the number of sprouts were measured at the end of October every year, the stem were cut above ground at the end of November from 1970 to 1976. The results are as follows: 1. The reproductive of the stems showed statistiaclly significant differences at 1% level by species and stock ages. L. bicolor showed the best reproductive capacity of them. 2. The sprouting ability was revealed that L. maximowiczii showed the best of them. 3. The reproductive capacity of stem, diameter, and number of sprouts increased with aging of stock up to 5 years on the investigated 5 species.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.52 no.1
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• pp.1-11
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• 2007

Light is an environmental component inevitably regulating photosynthesis and photo-morphogenesis, which are involved in the plant growth and development. Studies were conducted at the International Rice Research Institute, Philippines in 2004 and 2005, with aims to investigate 1) morphological responses of rice plants to low radiation, 2) morphological alteration of shade-grown plants when exposed to high light intensity, and 3) photosynthetic responses of shade-grown rice plants. Reduction in solar radiation by 40% induced increases in the area on a single leaf basis, biomass partitioning to leaves, and chlorophyll meter readings but brought about retardation of tiller development and decrease in above-ground biomass production of rice varieties. When the shade-grown plants from two weeks of transplanting to panicle initiation were exposed to full solar radiation after panicle initiation, they demonstrated less increase in chlorophyll meter readings and more decrease in leaf nitrogen concentrations from panicle initiation to flowering than control plants that were grown under the ambient solar radiation for whole growth period after transplanting. Shade-grown rice plants exhibited lower carbon assimilation rates but higher internal $CO_2$ concentrations on a single leaf basis than control plants, when measurements for shade-grown rice plants were made under the shading treatments. But when the measurements for shade-grown plants were made under the full solar radiation, light-saturated carbon assimilation rates were similar to control plants. Response of photosynthetic rates to varying light intensities was not considerably different between shading treatments and control. Yield reduction was observed in the shading treatments from panicle initiation to flowering and from flowering to physiological maturity, mainly by less spikelets per panicle and poor grain filling, respectively.

• Korean Journal of Remote Sensing
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• v.34 no.6_4
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• pp.1545-1553
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• 2018

Recent eruptive activity at Kīlauea Volcano started on at the end of April in 2018 showed rapid ground deflation between May and June in 2018. On summit area Halema'uma'u lava lake continued to drop at high speed and Kīlauea's summit continued to deflate. GPS receivers and electronic tiltmeters detected the surface deformation greater than 2 meters. We explored the time-series surface deformation at Kīlauea Volcano, focusing on the early stage of eruptive activity, using multi-temporal COSMO-SkyMed SAR imagery. The observed maximum deformation in line-of-sight (LOS) direction was about -1.5 meter, and it indicates approximately -1.9 meter in subsiding direction by applying incidence angle. The results showed that summit began to deflate just after the event started and most of deformation occurred between early May and the end of June. Moreover, we confirmed that summit's deflation rarely happened since July 2018, which means volcanic activity entered a stable stage. The best-fit magma source model based on time-series surface deformation demonstrated that magma chambers were lying at depths between 2-3 km, and it showed a deepening trend in time. Along with the change of source depth, the center of each magma model moved toward the southwest according to the time. These results have a potential risk of including bias coming from single track observation. Therefore, to complement the initial results, we need to generate precise magma source model based on three-dimensional measurements in further research.