• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.15 no.5
• /
• pp.125-133
• /
• 2016

Data processing capacity and speed are rapidly increasing due to the development of hardware and software in recent time. As a result, data usage is geometrically increasing and the amount of data which computers have to process has already exceeded five-thousand transaction per second. That is, the importance of Big Data is due to its 'real-time' and this makes it possible to analyze all the data in order to obtain accurate data at right time under any circumstances. Moreover, there are many researches about this as construction of smart factory with the application of Big Data is expected to have reduction in development, production, and quality management cost. In this paper, system using In-Memory Data Grid for high speed processing is implemented in semiconductor process which numerous data occur and improved performance is proven with experiments. Implemented system is expected to be possible to apply on not only the semiconductor but also any fields using Big Data and further researches will be made for possible application on other fields.

• Proceedings of the KSR Conference
• /
• 2007.11a
• /
• pp.1303-1308
• /
• 2007

Recently, precast concrete tracks are replacing ballast track for efficient and economic maintenance of track. Precast concrete railroad tracks are manufactured in factory, and transported to railroad construction site for installation. Therefore, quality of precast concrete track itself should be sufficiently good. On the contrary to the convenient manufacturing of precast concrete track, the installation of a precast concrete track requires careful steps. Typically, a precast concrete track is placed on an approximately 15-cm thick lean concrete layer. A mortar is filled between lean concrete layer and precast concrete track to adjust the sloping angle of a precast concrete track for a safe train operation at a curvy section. Then, the use of filled mortarproduces a void underneath a precast concrete track, which is harmful to structural safety of a precast concrete track undercyclic loading. Therefore, it is essential to make sure that there is no void left beneath a precast concrete track after mortar filling. In the continuous resonance method, the amplitude of frequency response measured using an instrumented hammer and an accelerometer is plotted against a pseudo-depth, which is half of the wave velocity divided by frequency. The frequency response functions are measured at consecutive measurement locations, 6-cm interval between measurement points, and then combined together to generate a 2-D plot of frequency response. The sections with strong reflections or large amplitude of frequency response are suspicious areas with internal voids and unfilled areas. The 2-D frequency response plot was efficient in locating problematic sections just by examining the color shade of a visualized plot in 2-D format. Some of the problematic sections were drilled to make a visual inspection of mortar filling. The visual image of interface between mortar and precast concrete track was verified using the validity of the continuous resonance technique adopted in this research.

• Journal of the Korean Society of Hazard Mitigation
• /
• v.6 no.4 s.23
• /
• pp.1-6
• /
• 2006

In terms of the speed-up of the conventional line, the research for a improved turnout was carried out continually around world. A turnout is known that it is the most unstable equipment structurally in the rail system. So, the turnout is needed more stable structure. An accurate assembly of turnout affects traveling qualify of turnout area and running safety. Therefore, a turnout which is pre-assembled at a factory by using the split PC sleeper is transported to construction site recently in advanced countries. In this paper, the performance measurements which estimate the safety of the split PC sleepers which are adopted for the first time to improve performance of turnout are implemented indoors. The split PC sleeper is one of components of the improved turnout. The test is considered of the worst ballast condition under the maintenance work as like STT(Swithc Tie Tamper) or MTT(Multiple Tie Tamper). These experiments results indicate that structural safety for the expansion joint of the split PC sleepers.

• Journal of the Korea Safety Management & Science
• /
• v.19 no.1
• /
• pp.15-25
• /
• 2017

The findings were summarized as follows. The safety check by manufacturer showed that 6 of 13 companies are over the average occurrence of defects. It was expected that there would be a difference between manufacturing technology capability and production system of each manufacturer. Consequently, manufacturers should institutionally improve and strengthen certification items for the upward standardization of safety certification before factory. Second, the safety check by year showed that the results of this study accord with those of previous studies on defect time. Consequently, manufacturers should classify the 3-year-old equipment for vehicle-mounted MEWP into a special check subject to do a nondestructive test according to proven results, and also reflect the test in a safety test system to do regular preventive activities of equipment defects. Third, the safety check by part showed that the boom and outrigger parts of vehicle-mounted MEWP have the most defects. Stress concentration resulted in defects as the boom part was most frequently operated in the structural parts for a real work. To prevent this, it is suitable to improve the hardness of boom materials. The outrigger part needs improvement in safety devices with materials. As an outrigger supports the overturning moment of equipment, it is most affected by its load based on the operating radius, resulting in fatigue crack.

• Journal of the Korea Convergence Society
• /
• v.11 no.9
• /
• pp.15-20
• /
• 2020

Software-related training can be considered essential in situations where software is an important factor in national innovation, growth and value creation. As one of the implementation methods for engineering education, various education through virtual simulations that can educate difficult situations in a similar environment are being conducted. Recently, the construction of smart factories at production and manufacturing sites is spreading, and product inspections using vision systems are being conducted. However, it has many difficulties due to lack of operation technology of vision system, but it requires a lot of cost to construct the system for education of vision system. In this paper, provide an educational virtual simulation model that integrates computer and physics engine camera functions and can extract and transmit video. It is possible to generate an image of 30Hz or more at an average of 35.4FPS of the experimental results of the proposed model, and it is possible to send and receive images in a time of 22.7ms, which can be utilized in an educational virtual simulation educational environment.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.15 no.6
• /
• pp.110-117
• /
• 2011

Seashore landfill projects use undersea pump dredging method for construction of airport and factory site. Coarse grain soil from the dredging is considered for use at inland. West sea shore bottom consists of primarily coarser grained silt-sand and this component contains far more percentage than is the case with East sea and South sea area. This soil shows very different characteristic at consolidation and compaction behavior. This research targets to utilize this type of dredging soil. Test specimen is from West sea (Saemangum) dredged soil landfill site. Model analysis is done for getting prediction of original soil relative density and N-value from dynamic compaction energy variance. Dynamic compaction energy is calculated for efficient foundation design.

• Korean Journal of Community Nutrition
• /
• v.3 no.4
• /
• pp.655-667
• /
• 1998

The Computer-assisted Hazard Analysis and Critical Control Point(HACCP) program has been developed for a systematic implementation of HACCP principles in identifying, assessing and controlling hazards in institutional foodservics operations. The HACCP-based sanitation evaluation tool has been developed, based on the results of the computerized assisted HACCP program in 4 service sites of C contracted foodservice company, including 2 general hospitals with 650-beds, one office operation of 400 meals per day, and one factory foodservice of 1,000 meals per day. All database files and processing programs were created by using Unify Vision tool with Windows 95 of user environments. The results of this study can be summarized as follows : 1. This program consists of the pre-stage for HACCP study and the implementation stage of the HACCP system. 1) The pre-stage for HACCP study includes the selection of menu items, the development of the HACCP recipe, the construction of product flow diagrams, and printing the HACCP recipes and product flow diagrams. 2) The implementation of the HACCP system includes the identification of microbiological hazards, the determination of critical control points based on the decision tree base files. 3) The HACCP-based sanitation evaluation tool consisted of 3 dimensions of time-temperature relationship, personal hygiene, and equipment-facility sanitation. The Cronbach's alphas calculation indicated that the tool was reliable. The results showed that the focus groups rated the mean of importance in time-temperature relationship, personal hygiene, and equipment-facility sanitation as 4.57, 4.59 and 4.55 respectively. Based on the results, this HACCP-based sanitation evaluation tool was considered as an effective tool for assuring product quality. This program will assist foodservice managers to encourage a standardized approach in the HACCP study and to maintain a systematic approach for ensuring that the HACCP principles are applied correctly.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.23 no.7
• /
• pp.829-836
• /
• 2019

IoT devices are widely used in network construction and are increasing. If necessary, heterogeneous IoT devices are used for data transmission. This paper proposes to prevent the method of data loss due to differences in throughput when the local network is constructed by Bluetooth 5 and long range network does by LoRa(Long Range). Data loss occur when the data transmits through LoRa, due to the throughputs of Bluetooth 5 faster than that of LoRa. The prevent method proposed by this paper can apply not only Bluetooth 5 and LoRa but heterogeneous IoT devices and expect to prevent data loss due to differences in throughput between heterogeneous IoT devices. Also, this paper shows the simulation result by applying the proposed avoid method. In this paper, two way to the preventive method shows the data transmission ratio and amount of memory that of necessity.

• Journal of the Korean Society of Safety
• /
• v.34 no.2
• /
• pp.40-47
• /
• 2019

The Half-depth precast deck is a structural system that utilizes pre-cast panels pre-built at the factory as formwork at the construction stage and as a major structural member at the same time after completion. These systems have joints between segments, and the detail and performance of the joints are factors that have a very large impact on the quality, such as the constructability and durability of the bridge decks. In this study, strength performance evaluation was performed for improved joints using connecting rebar by experimental method. Static loading tests were conducted on the test specimen with improved joint, those with existing joint and those without joint. The test results of the specimens were compared to each other, and the flexural strength required by the design was compared. The flexural strength required in the design was presented by finite element analysis. It has been shown that the flexural strength of the specimens with joints were more than twice that required by the design. But the flexural strength of the specimen with existing joint was about 84% of that without joint. The flexural strength of the specimen with improved joints was a nearly similar degree of that compared to the specimen without joint. And a comparison of the moment-deflection relationship curves of the two specimens also shows a very similar flexural behavior. It is confirmed that improved joint has sufficient flexural strength. In addition to strength, the bridge decks require serviceability, such as deflection and cracking, and in particular, fatigue resistance due to repetitive live loads is an important performance factor. Therefore, further verification studies are required.

• International journal of steel structures
• /
• v.18 no.5
• /
• pp.1639-1653
• /
• 2018

Bolted connections are suitable due to high quality prefabrication in the factory and erection in the workplace. Prefabrication and modularization cause high speed of erection and fabrication, high quality and quick return of investment. Their technical hitches transportation can be removed by prefabrication of joints and small fabrication of components. Box-columns are suitable members for bolted structures such as welded steel structures with moment frames in two directions etc., but their continual fabrication in multi-story buildings and performing the internal continuity plate in them will cause some practical dilemmas. The details of the proposal technique introduced here, is to remove such problems from the box columns. Besides, some other advantages include new prefabricated bolted beam-to-column connections referred to BBCC. This connection is a set of plates joined to columns, beams, support, and bolts. For a better understanding of its fabrication and erection techniques, two connection and one structural maquettes are made. The present work aims to study the cyclic behavior of connection numerically. To verify the accuracy of model, a similar tested connection was modelled. Its verification was then made through comparison with test results. The behavior of connection was evaluated for an exterior connection using three different support shapes. The effects of support shapes on rigidity, ductility, rotation capacity, maximum strength, four rad rotation strength were compared to those of the AISC seismic provision requirements. It was found that single beams support has all the AISC seismic provision requirements for special moment frames with and without a continuity plate, and box with continuity plate is the best support in the BBCC connection.