• Journal of the Korea Society for Simulation
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• v.32 no.4
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• pp.11-18
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• 2023

This study analyzes the effect of a handshake location of an AS/RS with twin cranes for mixed-model production line at an automobile plant. Implementing a handshake operation has the advantage for preventing route interference between twin cranes that operate without crossing into each other's working areas. However the handshake operation requires additional unloading and loading processes to retrieve assembly parts beyond the handshake area. Therefore the decision regarding the handshake location is crucial to improve efficiency of storage and retrieval operations. Simulation results show that the handshake operation with the optimal handshake location reduces the average response time of storage requests to 87% compared to non-handshake operation.

• Geophysics and Geophysical Exploration
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• v.10 no.3
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• pp.173-182
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• 2007

It is well known that manganese nodules enriched with valuable metals are abundantly distributed in the abyssal plain area in the Clarion-Clipperton (C-C) fracture zone of the northeast Pacific. Previous studies using deep-sea camera (DSC) system reported different observations about the relation of seafloor topographic change and nodule abundance, and they were sometimes contradictory. Moreover, proper foundation on the estimation of DSC underwater position, was not introduced clearly. The variability of the mining condition of manganese nodule according to seafloor topography was examined in the Korea Deep Ocean Study (KODOS) area, located in the C-C zone. In this paper, it is suggested that the utilization of deep towing system such as DSC is very useful approach to whom are interested in analysing the distributional characteristics of manganese nodule filed and in selecting promising minable area. To this purpose, nodule abundance and detailed bathymetry were acquired using deep-sea camera system and multi-beam echo sounder, respectively on the seamount free abyssal hill area of southern part ($132^{\circ}10'W$, $9^{\circ}45'N$) in KODOS regime. Some reasonable assumptions were introduced to enhance the accuracy of estimated DSC sampling position. The accuracy in the result of estimated underwater position was verified indirectly through the comparison of measured abundances on the crossing point of neighboring DSC tracks. From the recorded seafloor images, not only nodules and sediments but cracks and cliffs could be also found frequently. The positions of these probable unminable area were calculated by use of the recorded time being encountered with them from the seafloor images of DSC. The results suggest that the unminable areas are mostly distributed on the slope sides and hill tops, where nodule collector can not travel over.

• The Journal of Korean Academy of Prosthodontics
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• v.28 no.2
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• pp.183-197
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• 1990

The purpose of this study was to analyse the magnitude and distribution of stresses using a Photoelastic model from and distal - extension removable partial dentures With four designed indirect retainers. The designs of the indirect retainers were as follows : Design No. 1 : Aker's clasp on 1st bicuspid with no indirect retainer. Design No. 2 : Aker's clasp on 1st bicuspid with indirect retainer on canine. Design No. 3 : Extension of the reciprocal arm of Aker's clasp toward incisal rest on canine. Design No. 4 : Connection with the indirect retainer as in No. 2 and extension of reciprocal arm of Aker' s clasp. A photoelastic model was made of the epoxy resin(PL - 1) and hardner(PLH - 1) and coated with plastic cement -1(PC -1) at the lingual surface of the epoxy model and set with chrome - cobalt partial dentures. A unilateral vertical load of 10kg to the right 1st molar and a vertical load of 10kg to the middle portion of the metal bar crossing both the 1st molars of the right and left, were applied. With the use of specially designed jig, fixture; loading device and the reflective circular polariscope, we obtained the following results : 1. When the unilateral vertical load and the vertical load of the middle portion of the metal bar were applied, design No. 2, 3 and 4 exhibited the higher stress concentration at the root apices and their surrounding tissues of the primary and secondary abutment teeth. 2. When the unilateral vertical load applied to design No. 2,3 and 4 the root apices of the primary and secondary abutment teeth and their surrounding tissues and the nonloaded side of edentulous area exhibited and even stress distribution. 3. When the vertical load was applied, the stress concentration fringe in the primary and secondary abutment teeth was in the order of No. 1,4,2 and 3. 4. No.1 and 4 exhibited the higher distrorted stress concentration at the primary teeth and the edentulous area in the nonloaded side. 5. No.2 design reduced the stresses at the apices of the alveoli of the primary abutment teeth bilaterally as well as on the crest of the residual ridge on the nonloaded side. 6. No. 2 design exhibited the most favorable stress distribution.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.19 no.4
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• pp.45-54
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• 2020

This study investigated basic data on walking characteristics, including walking speed and cognitive-response for the elderly, and based on these, the time of walking signal was calculated. The on-site survey examined the actual pedestrian crossing speed using a stopwatch, and the age was divided into groups of ordinary people and the elderly. Analysis of the data showed that the average walking speed for the general public was 1.29 m/s, while the average walking speed for the elderly was 1.13 m/s, higher than that of the general public. In addition, the lower speed of the 15th percentile was analyzed to 1.01 m/s for the general population and 0.85 m/s for the elderly, showing a lower walking speed than the standard for the general area and 0.8 m/s for the protected area. However, for senior citizens who use walking sticks or wheelchairs, the speed of the lower 15th-percentile is 0.73 m/s, which is lower than the current standard of protected areas, according to the analysis.

• Journal of dental hygiene science
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• v.6 no.2
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• pp.119-125
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• 2006

This study executed questionnaire by own recording way using questionnaire to Dental Hygiene of W health science college and 365 students locating in Cholla-bukdo area from September 10, 2005 October 9. Distribution by class was first-year student 115 people, second-year student 125 people, third-year student 120 people, and collected data enforced crossing analysis, multiple response analysis, correlation analysis using statistical analysis program SPSS(V. 11.5) and significance level(${\alpha}$) used in all verifications was 0.05. 1. Seoul was the most to employment hope area and(p<0.01), there was difference that keep in mind statistically because appears salary highest about selection reason(p<0.001). 2. knowledge degree about can go to work appeared by 52.8% for doing not know, and when go to work 60.8% was thinking aptitude and interest most importantly and there was difference that keep in mind statistically(p<0.01). 3. when go to work 35.3% prevention medical examination and treatment business that 27.2% hopes dental management business appear(p<0.01). 4. I appeared accomplish result weak static correlation that analyze interrelation of degree of dictionary knowledge about can do interest degree about dental hygienist job and an employment(p<0.01).

• Tunnel and Underground Space
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• v.15 no.2 s.55
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• pp.111-118
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• 2005

The area of investigation belongs to Okchon metamorphic zone and the fault fractured zone runs parallel to the tunnel direction. It causes the independent decline of tunnel face and the slackness of the tunnel surrounding base so, after all, the severe displacement has occurred within the tunnel. Accordingly, the TSP(Tunnel Seismic Prediction) survey has been performed to investigate the extent of fault fractured zone and to analize its characteristics. Also, we have analized the behavior causes by performing the tunnel face mapping and drilling investigation, and confirmed the position and scale of geological anomaly area and front fractured zone which influences tunnel excavation and supporting. Collected data analyzed ground layer condition through 3 dimensional modeling. Several variables included in the modeling were analyzed by geostastistics. The analysis of the modeling data shows that the belt of weathering by fault fractured zone is developing on the basis of the right side of tunnel and that is decreasing to the left side. The fault fractured zone was confirmed that it has strike, $N0\~5^{\circ}E$ dip NW, and it is consisted of large-scale fractured zone including several anomalies. The severe displacement in tunnel is probably caused by asymmetrical load that n generated by the crossing of discontinuity and the rock strength imbalance of tunnel's both side by fault fractured zone, and judge that need tunnel reinforcement method of grouting etc.

• Geophysics and Geophysical Exploration
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• v.1 no.2
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• pp.101-109
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• 1998

Using airborne magnetic data, magnetic characteristics were studied at the Samryangjin caldera area developed in the volcanics of the Yuchon sub-basin, the south eastern part of the Gyeongsang basin. Residual magnetics, reduction to the pole, horizontal derivative, and vertical derivative maps are prepared. Using these maps, the magnetic lithofaces are zoned and the geological structures such as caldera and faults were qualitatively interpreted. In addition, the two quantitative interpretations were performed. Firstly, the forward modelling were done to the 14.5 line km crossing the caldera area to the northeast-southwest direction. Applying the 3-D Euler deconvolution method to the whole study area, the depth extent and the characteristics of the magnetic anomalous bodies were studied. According to the results, the magnetic lithofaces of the area are zoned by 4 units. In general, these are well matched with the geological distributions. But the biotite granites intruded in the northern boundary of the Samryangjin caldera show the high magnetic intensity, while the biotite granites of the other areas show the low magnetic intensity and the different magnetic lithofaces. Thus, we interpreted that the biotite granites are closely related with the volcanic activity of the Samryngjin caldera, and are intruded in the fracture zones developed along the caldera rim. The Samryangjin caldera and fault structures of the area can be easily recognized by the distinct magnetic structures from the various magnetic anomaly maps. Also the topographic characteristics well reflect these structures. The results of the forward modelling show that the magnetic basement depth of the Gyeongsang sedimentary basin is on the average about 6 km and in maximum 10 km. And the depth becomes shallower toward the caldera boundary due to the shallow intrusion of the volcanics. The results of the 3-D Euler method also show the caldera and fault structures. And the relatively shallow magnetic anomalous bodies which are related with the volcanics are generally developed to the east-west and northeast directions, while the deep magnetic anomalous bodies to the northwest direction.

• Journal of International Area Studies (JIAS)
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• v.15 no.1
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• pp.109-134
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• 2011

Drug-related crime has increased in spite of visible results of Uribe government's hard-line policies on drug eradication and illegally armed organizations which were pursued under U.S. support, without the accompaniment of quantity change in drug cultivation and trade. Military disputes of left-right illegally armed communities surrounding illegal crop cultivation rights were rather intensified, and the number of refugees was increased through enforced displaced people. The 2005 refugee registration committee RUPD reports that 3,316,862 people, 7.3% of total population, were refugees. In particular, the number of refugees presented a large increase rate of 624% when compared to the past year due to enforced displaced people. Main discharge areas of enforced displaced people are connected with drug crime and activities of illegally armed organizations, and are places of increased armed disputes in the process of occupied territory expansion of illegally armed communities and militia. Undiscriminated attacks were executed on farmers in the process of occupation of illegal crop cultivation sites by illegally armed organization and militia to emit enforced displaced people, who moved to border areas by crossing national borders. Enforced displaced people were restricted to certain areas before the appearance of Uribe administration. However, enforced displaced people not only presented quantitative expansion, but also showed tendency of nationwide expansion after national security policy was pursued. With the closing of the Amazon area, previously the main route of drug trade, activity base of illegally armed organizations was moved to the Pacific region, and Panama border area experienced refugee increase due to the new policy of enforced displaced people. This study aims to understand the actual condition and cause for the increase in refugees in Colombia based on border areas of Venezuela, which is the nation of highest dispersion of Columbian refugees, Panama, which has appeared as a new destination for refugees after the 90s, and Ecuador, which has experienced sudden refugee increase in 2000.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.4
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• pp.287-294
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• 2021

The objective of this study was conducted to calculate the damage of whole crop maize in accordance with abnormal climate using the forage yield prediction model through machine learning. The forage yield prediction model was developed through 8 machine learning by processing after collecting whole crop maize and climate data, and the experimental area was selected as Gyeonggi-do. The forage yield prediction model was developed using the DeepCrossing (R²=0.5442, RMSE=0.1769) technique of the highest accuracy among machine learning techniques. The damage was calculated as the difference between the predicted dry matter yield of normal and abnormal climate. In normal climate, the predicted dry matter yield varies depending on the region, it was found in the range of 15,003~17,517 kg/ha. In abnormal temperature, precipitation, and wind speed, the predicted dry matter yield differed according to region and abnormal climate level, and ranged from 14,947 to 17,571, 14,986 to 17,525, and 14,920 to 17,557 kg/ha, respectively. In abnormal temperature, precipitation, and wind speed, the damage was in the range of -68 to 89 kg/ha, -17 to 17 kg/ha, and -112 to 121 kg/ha, respectively, which could not be judged as damage. In order to accurately calculate the damage of whole crop maize need to increase the number of abnormal climate data used in the forage yield prediction model.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.4
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• pp.339-344
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• 1986

Frost damage which can reduce yields, impair fruit quality and cause loss of trees is closely related to the occurrence of daily minimum temperature. Horizontal distribution of air temperature minima can be characterized by conditions of radiational cooling and gravitational movement of cold air, which are influenced by the regional topographic features. Observations were made on the air temperature minima over Yangpyeong area, to delineate potential effects of topography on the temperature pattern during spring season. Two routes were selected for the observation. Liquid glass minimum thermometers were installed at 17 sites through the old peach orchards which had been closed due to the frequent freeze-frost hazards during the recent years. This route was 8.5km long and the highest point was 350m above mean sea level. The other route, which was 2.5km in distance, was run with a digital resistance thermometer during the hour just before sunrise. Observations were made both on a calm-clear day (April 30, 1986) and a windy-overcast day (May 1, 1986). The temperature on April 30 was in increasing trend with elevation but this was modified at near the riverside and the downtown area. An orchard lying on a hilltop showed the temperature $1^{\circ}C$ higher than near by lowland of which elevation was about 30m lower. The minimum temperature on the overcast day was little affected by terrestrial conditions but by the atmospheric lapse condition. The peach orchards severely damaged by cold air were found in the area where the lowest minimum temperature was observed. The results may be useful for selection of the proper orchard location to be developed in an area.