• Design & Manufacturing
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• v.11 no.1
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• pp.39-44
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• 2017

The domestic mold industry is composed of 6,560 small and medium sized mold companies as of 2015. The structure of mold industry centered on less than 10 people in the past has been improved in the direction of increasing number of medium and large scale companies with more than 20 competitors with global competitiveness and has maintained its position as the world's second largest mold exporter with global competitiveness. Nevertheless, the manpower structure and corporate competitiveness structure of the mold industry is very high, with the proportion of production manpower reaching 70% and shortage rate of 10% or more in order to respond to the orders of customers. However, the development base for new employees with technological skills required by the industrial field is poor, and the inflow of young people is very limited due to factors such as the avoidance of small and medium enterprises and production jobs. It is expected that the labor shortage of mold enterprises will be further increased in the future. In the mold industry, due to the characteristics of small quantity multi-product production corresponding to the demand of the consumer, many production processes are individually and independently carried out, resulting in low labor productivity, and the structural time required for the worker to increase the working time Due to limitations, the working hours per week of the employees are about 50 hours. The implementation of the working time reduction bill, which is recently promoted by the government, is a crisis factor. In order to cultivate the mold industry, it is necessary to expand the base of molds to meet the intensification of global competition, the convergence of technologies to actively respond to the restructuring of the industrial structure, and the response to the new industry, It is necessary to improve labor productivity through policies such as development and dissemination of system, and to secure price, delivery and quality competitiveness in global market.

• Journal of KIBIM
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• v.13 no.1
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• pp.1-12
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• 2023

The number of old buildings in Korea is increasing. According to a report from the Ministry of Land, Infrastructure and Transport, the proportion of old buildings increased from 29.0% in 2005 to 37.8% in 2009. However, the ratio of repairs to improve usability and improve the environment through problem improvement The proportion of old buildings was 72% in 2010, but decreased to 38% in 2020 and does not exceed 40%. The reason is that the difficulty of remodeling old buildings is more difficult than repairing new ones, and business estimates are difficult to predict. Accurately reflecting the current condition of a building in a repair project has a huge impact on time and budget. Accurate and detailed measurements are essential. Current repair methodologies require a lot of manpower, time and money to remodel an old building. Therefore, it is necessary to improve the remodeling methodology applied in the field. In this study proposed a Digital-Twin-based remodeling process that introduced various digital technologies such as 3D Scanning, BIM, Reverse Engineering, and Digital Fabrictation in consideration of the latest technologies used in recent construction projects. In addition, the process proposed in this study was applied to an actual small-scale building remodeling project and the results were analyzed. In addition, useful basic data were provided for the establishment of plans related to the repair process of buildings in the future.

• Journal of the Korean Society for information Management
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• v.40 no.4
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• pp.329-349
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• 2023

With the rapid development of information and communication technology, the speed of data production has increased rapidly, and this is represented by the concept of big data. Discussions on quality and reliability are also underway for big data whose data scale has rapidly increased in a short period of time. On the other hand, small data is minimal data of excellent quality and means data necessary for a specific problem situation. In the field of culture and arts, data of various types and topics exist, and research using big data technology is being conducted. However, research on whether basic information about culture and arts institutions is accurately provided and utilized is insufficient. The basic information of an institution can be an essential basis used in most big data analysis and becomes a starting point for identifying an institution. This study collected data dealing with the basic information of culture and arts institutions to define common metadata and constructed small data in the form of a knowledge graph linking institutions around common metadata. This can be a way to explore the types and characteristics of culture and arts institutions in an integrated way.

• Magazine of the Korean Society of Agricultural Engineers
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• v.21 no.2
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• pp.28-36
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• 1979

One of most important problems in the Monsoon Asia today is the production of rice paddy to meet the needs of the ever increasing population. Diversemeans are being employed to meet this demand, both by increasing productivity of existing farm land and by bringing further areas into cultivation. The primary step in either field is to ensure that there is sufficient moisture in the soil to suit the paddy, and at the same this means that excess moisture has to be drained off the land, while in others irrigat ion has to be employed to bring sufficient water to an area. In view of the fact that the project comprises a huge amount of earthwork, it can be carried out by extensive use of construction machinery in order to shorten the period. As farm ditch has a comparatively small section with shallow cutting depth, inaddition, there is lack of access road in the field, the excavation equipment with bulldozer or tracter-shovel (backhoe) type are not applicable because there are mostly adapted for the excavation of deep and wide section. Mini-backhoe with its bucket width not larger than 0. 3m, and width of blade not larger than 1. 00m seems to be more adaptable. About 80% of excavation of ditch section will be done by the machinery while the other 20% of excavation together with the finishing of the section are supposed to be done by man-power. The embankment of ditch section can be compacted by the crawler of backhoe when it is moving along the ditch for excavation. However, Lowland paddy field in the Monsoon Asia are made particulary in rain season, therefore, heavy machinery is not easy excavation for ditch. It is very important to know exact ground support power of the working site and select machines with corresponding ground pressure. Ground support power is variable subject to quality and water content of soil and therefore selection of machines should be made duly considering ground condition of the site at the time of construction works. Farm ditches dug and compacted by mannual labar are of poor quality and subject to destruction after one or two years of operation. On the other hand, excavation and compaction by bulldozer is not practical for ditches. Backboe is suitable for slope land, but this is required cycle time of bucket excavation and dumped out. If a small-scale farm ditch trencher adaptable to lowland paddy field is invented, such a machine could greatly accelerate the massive construction work envisaged in many countries and thus significantly speed up the most difficult part of irrigation development and management in Monsoon Asia.

• Korean Journal of Construction Engineering and Management
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• v.13 no.6
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• pp.133-142
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• 2012

With the recent changes in building environments such as low-carbon green growth, there have been increasing demands for the new building system that is eco-friendly and can maximize efficiency such as the unit modular system. For the unit modular system, more than 80% of the whole process is carried out in the factory while in the field, mostly unit module assembling and finish work are done. Thus, the quality at the pre-construction stage when design and manufacturing are done determines the quality of the building as a whole. In the country, the unit modular method was first applied in 2003 to school buildings and has gradually expanded afterwards, but due to the lack of examples and related information as well as the small scale of modular manufacturers, its characteristics have not been sufficiently reflected in design, manufacturing and field constructions. This study, as an attempt to improve the design quality of unit modular buildings, points to the problem in manufacturing and field construction, compares and analyzes its causes, and suggests major points to be considered in the early stage of designing the unit modular buildings.

• Journal of The Korean Astronomical Society
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• v.50 no.2
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• pp.29-39
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• 2017

We investigate two abnormal CME-Storm pairs that occurred on 2014 September 10 - 12 and 2015 March 15 - 17, respectively. The first one was a moderate geomagnetic storm ($Dst_{min}{\sim}-75nT$) driven by the X1.6 high speed flare-associated CME ($1267km\;s^{-1}$) in AR 12158 (N14E02) near solar disk center. The other was a very intense geomagnetic storm ($Dst_{min}{\sim}-223nT$) caused by a CME with moderate speed ($719km\;s^{-1}$) and associated with a filament eruption accompanied by a weak flare (C9.1) in AR 12297 (S17W38). Both CMEs have large direction parameters facing the Earth and southward magnetic field orientation in their solar source region. In this study, we inspect the structure of Interplanetary Flux Ropes (IFRs) at the Earth estimated by using the torus fitting technique assuming self-similar expansion. As results, we find that the moderate storm on 2014 September 12 was caused by small-scale southward magnetic fields in the sheath region ahead of the IFR. The Earth traversed the portion of the IFR where only the northward fields are observed. Meanwhile, in case of the 2015 March 17 storm, our IFR analysis revealed that the Earth passed the very portion where only the southward magnetic fields are observed throughout the passage. The resultant southward magnetic field with long-duration is the main cause of the intense storm. We suggest that 3D magnetic field geometry of an IFR at the IFR-Earth encounter is important and the strength of a geomagnetic storm is strongly affected by the relative location of the Earth with respect to the IFR structure.

• Journal of Korean Library and Information Science Society
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• v.37 no.1
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• pp.193-219
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• 2006

This study analyzes 47 articles dealing with refugees in library and information science field. The subjects of these articles are such various as the cases of refugee service in libraries and information centers, the library service guidance for refugees, information resources of refugees and forced migration study, and information need and Information seeking behavior of refugees. However, the research of this area has such limitations and weakness as the small scale of articles about refugees, the scarcity of professional researchers, the deficient studies concentrating refugees directly, and the unprepared research methods. Tn particular, there was no article about refugee which was produced by the library and information science field in South Korea. Urgently needed is the research of information needs and information seeking behavior of North Korean refugees considering the recent influx of North Korean refugee into South Korea.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.6
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• pp.669-676
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• 2016

A field study was conducted to determine the runoff loss of N and P in small scale of red pepper field plots (10% slope), consisting of three different plots with black polyethylene vinyl mulching (mulching), ridge without mulching (ridge), and flat without ridge and mulching (flat). Composted manure and urea as a basal application were applied at rates of $20MT\;ha^{-1}$ and $93kg\;N\;ha^{-1}$, respectively. Urea at $189kg\;N\;ha^{-1}$ and fused phosphate at $67kg\;P_2O_5\;ha^{-1}$ were additionally applied on June 25 with different fertilization methods, broadcast application in flat plot and hole injection in ridge and mulching plots. Plant uptake of N and P was positively correlated with their respective concentrations in surface soil: mulching > ridge > flat plots. The runoff loss by soil erosion was higher in flat plot than ridge and mulching plot with contour line. Nitrate loss by the runoff water had no significant differences among three surface management practices, but the higher average value in ridge and mulching plots than flat plot. Especially, the flat plot had no phosphate loss during summer season. This is probably due to low labile P content in surface soil of flat plot. In the summation of soil and water loss, flat plot was higher in N and P loss than ridge and mulching plot with contour line. Nevertheless, the nitrate and phosphate loss by runoff water could be more important for non-point source management because the water could meet the river easier than eroded soil because of re-deposition around slope land.

• Structural Monitoring and Maintenance
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• v.1 no.1
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• pp.131-157
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• 2014

Special track systems used to divert a train to other directions or other tracks are generally called 'railway turnout'. A traditional turnout system consists of steel rails, switches, crossings, steel plates, fasteners, screw spikes, timber bearers, ballast and formation. The wheel rail contact over the crossing transfer zone has a dip-like shape and can often cause detrimental impact loads on the railway track and its components. The large impact also emits disturbing noises (either impact or ground-borne noise) to railway neighbors. In a brown-field railway track where an existing aged infrastructure requires renewal or maintenance, some physical constraints and construction complexities may dominate the choice of track forms or certain components. With the difficulty to seek for high-quality timbers with dimensional stability, a methodology to replace aged timber bearers in harsh dynamic environments is to adopt an alternative material that could mimic responses and characteristics of timber in both static and dynamic loading conditions. A critical review has suggested an application of an alternative material called fibre-reinforced foamed urethane (FFU). The full-scale capacity design makes use of its comparable engineering characteristics to timber, high-impact attenuation, high damping property, and a longer service life. A field trial to investigate in-situ behaviours of a turnout grillage system using an alternative material, 'fibre-reinforced foamed urethane (FFU)' bearers, has been carried out at a complex turnout junction under heavy mixed traffics at Hornsby, New South Wales, Australia. The turnout junction was renewed using the FFU bearers altogether with new special track components. Influences of the FFU bearers on track geometry (recorded by track inspection vehicle 'AK Car'), track settlement (based on survey data), track dynamics, and acoustic characteristics have been measured. Operational train pass-by measurements have been analysed to evaluate the effectiveness of the replacement methodology. Comparative studies show that the use of FFU bearers generates higher rail and sleeper accelerations but the damping capacity of the FFU help suppress vibration transferring onto other track components. The survey data analysis suggests a small vertical settlement and negligible lateral movement of the turnout system. The static and dynamic behaviours of FFU bearers appear to equate that of natural timber but its service life is superior.

• Journal of Fisheries and Marine Sciences Education
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• v.17 no.2
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• pp.193-208
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• 2005

The object of this study is to provide a framework of increasing the effectiveness of the R&D planning of experts in fisheries and the education of students with the theoretical background and analytical skills through the adoption of technology roadmapping process in the marine production industry. The study was conducted by fact-finding surveys and the response content for surveys obtained from each expert advisor in the field of fisheries and maritime affairs such as fishery industries, some government organizations and research institutes including the Ministry of Maritime Affairs and Fisheries (MOMAF), National Fisheries Research and Development Institute (NFRDI) and fisheries-related universities was analyzed. The major implementation tasks to effectively achieve the basic goals of technology roadmap for short and middle-term research and development in the fisheries production field are as follows: 1. Research in order to achieve the realization of community-based resource management fisheries or fishermen-oriented co-management fisheries with paradigm shift in fisheries management. 2. Research in order to derive the construction of cost reducing and manpower saving systems in fishery-related science, technology and engineering. 3. Research in order to create the high value-added fisheries products with a focus on the upgrading of processing, freezing and refrigerating facilities, the reduction of logistics costs and the minimization of distribution steps. 4. Research in order to achieve the realization and development of environmental-friendly fisheries and internationally competitive fisheries through restructuring the entire fishing industries, in particular, small-scale fisheries. 5. Research in order to achieve the effective utilization of fisheries resources with a new creation of clean and living marine environment by fisherman under the balanced management and protection of marine living resources and fishing grounds.