• Korean Journal of Remote Sensing
• /
• v.38 no.6_1
• /
• pp.1257-1271
• /
• 2022

Recently, many Earth observation optical satellites have been developed, as their demands were increasing. Therefore, a rapid preprocessing of satellites became one of the most important problem for an active utilization of satellite images. Satellite image matching is a technique in which two images are transformed and represented in one specific coordinate system. This technique is used for aligning different bands or correcting of relative positions error between two satellite images. In this paper, we propose an automatic image matching method among satellite images with different ground sampling distances (GSDs). Our method is based on improved feature matching and robust estimation of transformation between satellite images. The proposed method consists of five processes: calculation of overlapping area, improved feature detection, feature matching, robust estimation of transformation, and image resampling. For feature detection, we extract overlapping areas and resample them to equalize their GSDs. For feature matching, we used Oriented FAST and rotated BRIEF (ORB) to improve matching performance. We performed image registration experiments with images KOMPSAT-3A and RapidEye. The performance verification of the proposed method was checked in qualitative and quantitative methods. The reprojection errors of image matching were in the range of 1.277 to 1.608 pixels accuracy with respect to the GSD of RapidEye images. Finally, we confirmed the possibility of satellite image matching with heterogeneous GSDs through the proposed method.

• Journal of Digital Convergence
• /
• v.19 no.5
• /
• pp.423-432
• /
• 2021

The purpose of this study is to investigate the effect of role recognition of students participating in middle school soccer club activities applying sports education model on responsibility and self-directed learning. In order to achieve this purpose, 410 samples were selected from male students based in Busan using the convenience sampling method. Among them, and 370 data were finally verified through frequency analysis, exploratory factor analysis, Cronbach's α coefficient calculation, and correlation analysis using the SPS statistics 25.0 program. Finally, a regression analysis was performed for hypothesis testing, and the results were as follows. First, the awareness of the role of the student participating in middle school soccer club activities, which applied the sports education model, was found to have a positive effect in part on the sense of responsibility. Second, the role recognition of students participating in middle school soccer club activities, which applied the sports education model, was found to have a partial positive influence on self-directed learning. Finally, the responsibility of students participating in middle school soccer club activities, which applied the sports education model, was found to have a positive effect on self-directed learning in part. Therefore, physical education teachers should ensure that students can choose the right roles for themselves through various role experiences in soccer classes so that more active learning can take place.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.28 no.6
• /
• pp.874-881
• /
• 2022

Until 2016, before discussions on the restoration of brackish water of the Nakdong River Estuary started in earnest, the downstream water level was predicted using the data of existing tide level observatories (Busan and Gadeokdo) several kilometers away from the estuary. However, it was not easy to carry out the prediction due to the dif erence in tide level and phase. Therefore, this study was conducted to estimate tide prediction more accurately through tidal harmonic analysis using the measured water level affected by the tides in the offshore waters adjacent to the Nakdong River Estuary. As a research method, the storage status of observation data according to the period and abnormal data were checked at 10-minute intervals in the offshore sea area near the Nakdong River Estuary bank, and the observed and predicted tides were measured using TASK2000 (Tidal Analysis Software Kit) Package, a tidal harmonic analysis program. Regression analysis based on one-to-one comparison showed that the correlation between the two components was high correlation coef icient 0.9334. In predicting the tides for the current year, if possible, more accurate data can be obtained by harmonically analyzing one-year tide observation data from the previous year and performing tide prediction using the obtained harmonic constant. Based on this method, the predicted tide for 2022 was generated and it is being used in the calculation of seawater inflow for the restoration of brackish water of the Nakdong River Estuary.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.27 no.7
• /
• pp.1044-1050
• /
• 2021

After the occurrence of several passenger ship accidents in Korea, various systems are being developed for passenger ship safety management. A total of 162 passenger ships operate along the coast of Korea, of which 105 (65 %) are car-ferries with open vehicle decks. The car-ferry has a navigation pattern that passes through 2 to 4 islands. Safety inspections at the departure point(home port) are carried out by the crew, the operation supervisor of the operation management office, and the maritime safety supervisor. In some cases, self-inspections are carried out for safety inspections at layovers. As with any system, there are institutional and practical limitations. To this end, this study was conducted to suggest a method of detecting a vehicle using image processing and linking it to the calculations for ship stability. For vehicle detection, a method using a difference image and one using machine learning were used. However, a limitation was observed in these methods that the vehicle could not be identified due to strong background lighting from the pier and the ship in the cases where the camera was backlit such as during sunset or at night. It appears necessary to secure sufficient image data and upgrade the program for stable image processing.

• Journal of Industrial Convergence
• /
• v.20 no.11
• /
• pp.135-140
• /
• 2022

A study to estimate the appropriate size for the quota of civil servants during the period of change of government is required. Therefore, in this study, we would like to introduce a study that uses DEA to estimate the appropriate size of public officials. The department of a public institution is DMU, and the number of employees in each department is applied as an input variable, and the number of electronic approval production documents and the number of electronic approval expenditures are applied as output variables. MaxDEA 8 was used as an analysis program for this purpose. As a result of the analysis, when the efficiency level was 1.00 (100%), 3 out of 14 departments showed the optimal level by satisfying the efficiency, and 10 of the remaining departments scored 0.50 (50%) with a score of 0.50 (50%), confirmed to be relatively inefficient. In other words, it was confirmed that most departments had inefficient surplus staff. As an additional analysis, we calculated the number of possible staff reductions using the efficiency level. Using this, it is expected that the field of manpower reduction can be discovered in advance through an analysis of manpower efficiency by department, and based on this, it can be used to relocate manpower by department according to future response strategies.

• Journal of Industrial Convergence
• /
• v.20 no.11
• /
• pp.65-74
• /
• 2022

This study was attempted to determine the degree of self-determination motivation, interpersonal relationship harmony, and academic self-efficacy of freshmen admitted to the nursing department during the COVID-19 period, and to identify factors affecting academic self-efficacy. Data were collected from November 01 to November 30, 2021, and the subjects of this study were 220 freshmen enrolled in the Department of Nursing at a university located in C city. For data analysis, t-test, anova and scheffé's post hoc test, pearson correlation coefficients calculation and multiple regression analysis were performed using SPSS 25.0. As a result of the study, it was found that face-to-face learning experience in the first semester, the reason for choosing a major, self-determination motivation and interpersonal relationship harmony explained 47.9% of the total change in academic self-efficacy. And it was found that freshmen with face-to-face learning in the first semester, self-determination motivation and interpersonal harmony had a significant effect on academic self-efficacy. In order to improve the academic self-efficacy of the first year, a program to support self-determination motivation and harmonize interpersonal relationships should be developed and applied.

• Journal of the Korean Applied Science and Technology
• /
• v.40 no.2
• /
• pp.268-276
• /
• 2023

The purpose of this study is to investigate how the presence experience of virtual reality sports room class affects the intention to participate in sports activities when pleasure and immersion are experienced. For the survey, a total of 300 people, 60 copies each, were sampled for the upper grades of elementary school, and a total of 276 copies of data were used for the study, excluding 24 copies with insincere answers from among the questionnaires. The data processing used in this study was SPSS ver. 24.0 and AMOS ver. 24.0 Statistical program was used to perform confirmatory factor analysis, frequency analysis, Cronbach's α coefficient calculation, correlation analysis, and structural equation model analysis. Through this procedure, the following results were derived. First, the presence experience of the virtual reality sports room class had a positive effect on enjoyment. Second, the relationship between enjoyment and immersion in virtual reality sports room classes had a positive effect. Third, the enjoyment of the virtual reality sports room class had a positive effect on the intention to participate in sports activities. Fourth, the class immersion of the students who participated in the virtual reality sports room had a positive effect on their intention to participate in future sports activities.

• Korean Journal of Construction Engineering and Management
• /
• v.24 no.3
• /
• pp.12-19
• /
• 2023

In the case of the construction industry, the relationship between process and cost should be appropriately distributed so that the finished product can be delivered at the minimum fee within the construction period. At that time, it should be considered the size of the bridge, the construction method, the environment and production capacity of the factory, and the transport distance. However, due to various reasons that occur during the construction period, problems such as construction delay, construction cost increase, and quality and reliability degradation occur. Therefore, a systematic and scientific construction technique and process management technology are needed to break away from the conventional method. The prefab(Pre-Fabrication) is a representative OSC (Off-Site Construction) method manufactured in a factory and constructed onsite. This study develops a resource and process plan optimization system for the process management of the Nodular girder, a prefab bridge girder. A simulation algorithm develops to automatically test various variables in the personnel equipment mobilization plan to derive the optimal value. And, the algorithm was applied to the Paju-Pocheon Expressway Construction (Section 3) Dohwa 4 Bridge under construction, and the results compare. Based on construction work standard product calculation, actual input manpower, equipment type, and quantity were applied to the Activity Card, and the amount of work by quantity counting, resource planning, and resource requirements was reflected. In the future, we plan to improve the accuracy of the program by applying forecasting techniques including various field data.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.2
• /
• pp.419-427
• /
• 2024

This study assessed the potential impact of gas leakage resulting from accidental damage to buried urban gas pipelines during perforating operation near subway construction sites. The risk of explosions due to ignition sources such as static electricity, arising from gas infiltrating the subway construction site through storm sewers and sewage pipes, was evaluated using the ALOHA program. The results of the threat zone calculation, which input various parameters of urban gas pipelines such as length, diameter, and pressure, indicated that the flammable area within the vapor cloud extended from 1.2 to 1.4 km (red zone), the blast area ranged from 0.8 to 1.0 km (yellow zone), and the jet fire extended from 45 to 61 m (red zone). This study demonstrates that within the flammable area of the vapor cloud, a specific combination of concentration and conditions can increase flammability. The blast area may experience explosions with a pressure of 1.0 psi, sufficient to break glass windows. In the event of a jet fire, high temperatures and intense radiant heat exposure lead to rapid fire propagation in densely populated areas, posing a high risk of casualties. The findings are presented in terms of the sphere of influence and threat zone ranges.

• Korean Journal of Poultry Science
• /
• v.29 no.1
• /
• pp.37-43
• /
• 2002

This experiment was conducted to study the effect of early-life feed restriction with diet dilution on compensatory growth, feed efficiency and abdominal fat pad deposition in broilers. In this study, the chicks were randomly assigned to five treatments. Twenty chicks were assigned to each floor pen, and each dietary treatment was replicated with three pens. Birds In control group (C) were full-fed a starter diet throughout the experimental period, and all birds in four dietary treatments (T1-T4) were fed as starter diet diluted with 50% rice hulls. Birds in T1 were fed with a diluted starter diet ad libitum from 7- to 74-d. In T2,the feeding program was 1-d withdrawal alternating with 3-d feed and in T3 1-d withdrawal alternating with 2-d feed. The feeding Program in T4 was alternate days withdrawal and feeding. The feeding with the diluted starter diet (T1) did not significantly affect to growth rate as compared to the birds of C. When periods of 24 h feed withdrawal were Imposed in conjunction with the diluted diets, birds were under weight at 49 d. As the diluted diet treatment was combined with feed withdrawal (T2-T4), there were further less growth. During the 22 to 49 d Period,T1 birds had greater weight gain compared to other treatments (P<0.05) . Birds consumed less feed from 7- to 49-d when the rice hull dilution was used, and this effect was increased by imposition of feed withdrawal (P<0.07) . If rice hull was excluded from the calculation of feed intake (assumed indigestible) then Intake of the starter diet was markedly less for restricted vs. control birds. After 22 d and from 7 to 49 d, restricted birds had superior feed conversion (P<0.05) compared to control birds. Abdominal fat pad deposition and mortality were not influenced by early feed restriction by diluted diet (P<0.05) .