• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.10
• /
• pp.3911-3916
• /
• 2010

In this paper we describe contents and results on running test for ATP on-board equipment, which has propelled as one of the research projects, so called, "Reliability assessment and operation technology development for Korean-type tilting trains" in order to ensure the safety and operation efficiency of tilting trains. We developed tilting trains for the speed-up of conventional lines and for the passenger service improvement where the KTX is not available. And we made progress the operation trial test in the 120,000 km distance with the use of ATS equipment, used in existing lines, for the purpose of the reliability assessment of the developed tilting trains. We decided to accelerate the speed for more than 200km/h with respect to the 6 existing lines including Jungang-line and Chungbuk-line where KTX has not operated. According to this decision, Train control system is to be changed from ATS to ATP. We should have installed an ATP on-board unit in tilting trains and verified the operational suitability, therefore we installed the same ATP on-board unit on tilting trains as that used in the ATP construction project on Gyeongbu-line and Honam-line, and verified that the function and performance of the installed ATP on-board unit conformed to the tilting trains operation.

• Korean Journal of Environmental Agriculture
• /
• v.27 no.3
• /
• pp.231-238
• /
• 2008

This study proposed the method of phosphate recovery from municipal wastewater by using ferrous iron waste, generated from the mechanical process in the steel industry. In the analysis of XRD, ferrous iron waste was composed of $Fe_3O_4$ (magnetite), practically with $Fe^{2+}$ and $Fe^{3+}$. It had inverse spinel structure. In order to identify the adsorption characteristic of phosphate on ferrous iron waste, isotherm adsorption test was designed. Experimental results were well analyzed by Freundlich and Langmuir isotherm theories. Empirical constants of all isotherms applied increased with alkalinity in the samples, ranging from 1.2 to 235 $CaCO_3/L$. In the regeneration test, empirical constants of Langmuir isotherm, i.e., $q_{max}$ (maximum adsorption capacity) and b (energy of adsorption) decreased as the frequency of regeneration was increased. Experiment was further performed to evaluate the performance of the treatment scheme of chemical precipitation by ferrous iron waste followed by biological aerated filter (BAF). The overall removal efficiency in the system increased up to 80% and 90% for total phosphate (TP) and soluble phosphate (SP), respectively, and the corresponding effluent concentrations were detected below 2 mg/L and 1 mg/L for TP and SP, respectively. However, short-circuit problem was still unsolved operational consideration in this system. The practical concept applied in this study will give potential benefits in achieving environmentally sound wastewater treatment as well as environmentally compatible waste disposal in terms of closed substance cycle waste management.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.3
• /
• pp.679-686
• /
• 2018

A new dust cleaning vehicle is needed to remove fine and ultra-fine particulate matter in subway tunnels. Therefore, the recently developed tunnel cleaning vehicle is equipped with an efficient suction system and cyclone-based prefilter to handle ultra-fine particles. To treat various sizes of particulate matter with an underbody suction system, this paper proposes a cyclone-based prefilter in the suction system and validates the dust removal efficiency through Computational Fluid Dynamics (CFD) analysis using ANSYS FLUENT. Using the created surface and volume mesh, various particle sizes, materials, and fan flow rates, the particles were tracked in the flow with a discrete phase model. As a result, the dust cleaning vehicle at a normal operational speed of 5km/h requires at least a fan flow rate of $1500m^3/min$ and 100mm of suction inlet height from the tunnel track floor. Those suction modules and cyclone-based prefilters in the dust cleaning vehicle reduces the dust accumulation load of the electric precipitator and helps remove the accumulated fine and ultra-fine dust in the subway tunnel.

• Journal of Intelligence and Information Systems
• /
• v.15 no.1
• /
• pp.103-122
• /
• 2009

The recent development of information technology has been envisioned as the next technological wave and is expected to play an important role in diminishing boundaries between business organizations. Enterprises have recently resulted in a surge in workflow management, making business processes sharable among different business organizations. To make heterogeneous workflows operational, it is crucial that workflow management systems provide efficient tools for an environment supporting interoperability of business processes among different business organizations. As the potential of workflow management is becoming widely recognized, the demand for an integrated framework that facilitates interoperability among heterogeneous workflows is concomitantly growing. Despite the large body of work in the area of workflow management, few efforts are directed towards identifying conflict patterns for heterogeneous workflow interoperability of inter-organizational business processes. In this paper, we summarize state of the art research trends in workflow management research area and identify conflict patterns for heterogeneous workflows. We believe that this is one of the first attempts to conceptualize conflict patterns that exist on inter-organizational business processes. This paper opens up a novel avenue for workflow management research by supplementing the existing conceptual frameworks for workflow management.

• The Journal of the Korea Contents Association
• /
• v.14 no.1
• /
• pp.455-465
• /
• 2014

This study focuses on some institutional improvement for revitalization of change in building use of officetel to lifestyle lodging industry. First as analysis method, this study establishes a failure factor for change in building use of officetel to lifestyle lodging industry. Second, analyzes an urgent importance to improve it in aspect of a legal institution or management for revitalizing a change of building use of officetel to lifestyle lodging industry. As a result, a failure factor of change in building use from officetel to lifestyle lodging industry is deducted in 4 articles with 13 detailed index. As a result of AHP, 'existing contractor's 100% agreement condition' is the first place, 'commercial /semi-residential area in zoning' is the second place, 'relative cleanup zone' is the fourth place, 'late changes of building use by a complex licensing procedure' is the fifth place, 'operational risk of consignment' is the sixth place, 'deficiency in publicity of related institution' is the eighth place, 'lack of concept in lifestyle lodging industry of building code' is the ninth place, 'basic constructional condition such as parking lot sewage and fire protection system' is the tenth plce, 'installation of ventilation facility' is the eleventh place, 'installation of bathroom and shower room in each room' is the twelfth place, 'installation of kitchen facility' is the thirteenth place.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.6 no.4
• /
• pp.39-57
• /
• 2011

In this study, entrepreneurship opportunities, get in anywhere, in any situation, whether in respect to entrepreneurship through empirical research is to analyze. In addition, young entrepreneurs and entrepreneurship opportunities to target the source and a realistic opportunity to investigate the nature of the search in terms of effective support for young entrepreneurs and operational plans to seek the help. Entrepreneurship opportunities of the origins of the existing studies individually being taken were young entrepreneurs and selected for this study the national and international literature base, and objectives of the study to achieve the city "Young Entrepreneurs 1000 Project" participants, survey through the empirical foundation of their opportunities and entrepreneurship opportunities origins analyzed the relationship between sources. Source of entrepreneurship opportunities in the establishment will include the nature of existing research (intentional / unintentional), business opportunities generated background (source), business opportunity lead, business opportunity lead contact situation (the nature of chance encounters), the business idea was dealt with using here, a new source of opportunity factor established by adding the capital adequacy ratio of capital has been studied. Also 10 years ago by byeong-ju, Jo. entrepreneurship opportunities in Korea for the first time research on the relationship between the source after source of opportunities than in previous research literature on factors leading to the establishment an opportunity to add a set of relationships between sources were analyzed.

• Journal of the Korean Institute of Gas
• /
• v.14 no.3
• /
• pp.26-34
• /
• 2010

KOGAS, established in 1983 by law to ensure stable gas supply to the public, is responsible for the wholesale distribution to 30 city gas companies that deal with the retail distribution of natural gas in their geographic areas. The gas imported by KOGAS is measured by checking the level difference of LNG shipped in tankers before and after unloading. The analysis of gas composition is essential because the imported gas price is determined by its calorific value. The turbine meter is widely used for measuring the gas sold to city gas companies. Unlike the metering system for power plants, there is no gas chromatograph since the custody transfer of gas to the city gas companies is not billed by calorific value, but by volume basis. The gas quantity that a city gas company has bought from KOGAS is not equal to the quantity that the company sold to its customers. There have been some discrepancies between the wholesale gas meter readouts and retail ones due to some inherent errors of meters and some operational issues of the meters. This paper investigates the controversies regarding the real quantity of gas between distributors and consumers. It will discus and suggest desirable policies, both technically and economically, in order to solve the discrepancies of gas measurement.

• Korean Institute of Interior Design Journal
• /
• v.24 no.6
• /
• pp.202-211
• /
• 2015

This study attempts to deduce the necessity and validity of complexation, and suggests complexation through complexation suitability evaluations as follows. First, the concept and current state of leisure facilities for the elderly and elementary facilities and architectural complexation were investigated through theoretical considerations. Second, the target schools for complexation of 'elementary school-leisure facility for the elderly' were selected. The aspects of facility introduction of an elementary school, teacher support facility, convenience facility for the disabled, safety and security facilities as well as school facility accessibility were investigated on the basis of the data attained from theoretical considerations. Third, the feasibility of complexation of leisure facilities for the elderly was reviewed, based on the investigated data on complexation-targeted elementary school. Regarding school building and support facilities, with a focus on leisure programs for the elderly, the availability and number of rooms, extra numbers of regular classrooms and the room condition were assessed on the basis of the analysis of operational perspective of each facility. The convenience facilities for the disabled were examined by classifying them into interventional facility in consideration of facilities for the elderly, pursuant to the provisions in the convenience promotion assurance act for the disabled, elderly and pregnant women. Safety and security facilities were evaluated in an effort to assess the safety issue of the elderly and children. The result of the evaluation of the 6 elementary schools in Seong-buk county based on the above-mentioned four measurement standards shows that they scored 107~124 points out of the total 155 points, with the average of 118.5 points. This is more than the medium score and shows the possible complexation of the elementary school facilities as the leisure facilities for the elderly, and at the same time it may lead each school to find out the elements conducive to enhancing the complexation as a result of the evaluation. Through the evaluation data, I expect that we contribute to promoting the process of the evaluation of the appropriateness of complexation and the efficient complexation.

• Journal of Electrical Engineering and Technology
• /
• v.13 no.6
• /
• pp.2402-2411
• /
• 2018

Fluoronitriles-$CO_2$ gas mixtures are promising alternatives to $SF_6$ in environmentally-friendly gas-insulated transmission lines (GILs). Insulating gas heat transfer characteristics are of major significance for the current-carrying capacity design and operational state monitoring of GILs. In this paper, a three-dimensional calculation model was established for a GIL using the thermal-fluid coupled finite element method. The calculated results showed close agreement with experimentally measured data. The temperature distribution of a GIL filled with the Fluoronitriles-$CO_2$ mixture was obtained and compared with those of GILs filled with $CO_2$ and $SF_6$. Furthermore, the effects of the mixture ratio of the component gases and the gas pressure on the temperature rise and current-carrying capacity of the GIL were analyzed. Results indicated that the heat transfer performance of the Fluoronitriles-$CO_2$ gas mixture was better than that of $CO_2$ but worse than that of $SF_6$. When compared with $SF_6$, use of the Fluoronitriles-$CO_2$ gas mixture caused a reduction in the GIL's current-carrying capacity. In addition, increasing the Fluoronitriles gas component ratio or increasing the pressure of the insulating gas mixture could improve the heat dissipation and current-carrying capacity of the GIL. These research results can be used to design environmentally-friendly GILs containing Fluoronitriles-$CO_2$ gas mixtures.

• Journal of the Korean Society for Nondestructive Testing
• /
• v.14 no.2
• /
• pp.122-131
• /
• 1994

Journal bearings in the rotating machineries are vulnerable to the contamination or the insufficient supply of lubricating oil, which is likely to be the cause of unexpected shutdown or malfunction of these systems. Various destructive and nondestructive testing methods had been used for the reduction of maintenance cost and the operational safety problems due to the accidents related to bearing damages. In this experimental approach, acoustic emission monitoring is employed to the detection of incipient failure caused by intervention of foreign particles most probable in the journal bearing systems. Experimental schedules for the intervention of foreign particles was composed to be more quantitative and systematic than last study in consideration of minimum oil film thickness and particle size. The experiment was conducted under such designed conditions as inserting alumina particles to the lubrication layer in the simulated journal bearing system. Several parameters such as AE rms level, waveform, AE energy distribution and other AE event parameters are used for analysis and characterization of damage source. The results showed that the history of damage was well correlated with the changes of AE rms level and the type of damage source signal can be verified using other informations such as waveform, distributions of AE parameters etc.