• Journal of the Korean Society of Safety
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• v.29 no.6
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• pp.144-150
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• 2014

A man is a component of a large system how complex it may be so that human performance which can influence on the system safety should be included in system safety assessment. Meanwhile, human performance can vary over time due to lots of factors. Among them, stress is an indirect factor that may cause human error which can result in industrial accidents. To assess stress level of human workers, not a few assessment tools have been developed. However, it can be questionable to utilize them for human performance anticipation because they were mainly developed with the viewpoint of mental health, though stress assessment can be also required in the safety aspect. Therefore, this study aimed to survey the possibility of their application with safety purpose. About 10 kinds of work stress tools were collected and analyzed with reference to assessment items, assessment and analysis methods, and follow-up measures. The results showed that most tools focused their weights on Demands, Supports, and Relationships, in sequence. However, they, except only one tool developed by the Japanese researchers, merely advised to set up counterplans in PDCA cycle or risk management activities. In consequence, application of stress assessment tools mainly developed for mental health seemed impractical for safety purpose with respect to human performance anticipation so that it was concluded that development of a new assessment tools aimed to human performance variation and accident prevention would be inevitable.

• The KIPS Transactions:PartD
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• v.8D no.2
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• pp.181-192
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• 2001

XML/EDI is different from traditional EDI because it offers the framework necessary for electronic commerce and extends the scope of the traditional EDI which focuses on data transfer. Since existing EDI services are moved to Internet platform and again to Web platform, users can use EDI in the integrated environment without inconvenience of using different EDI softwares, which have their own configurations. This paper describes the overall design and implementation of a Web-based XML/EDI system that is a core component for the electronic commerce. The constructed XML/EDI system in this paper is comprised of document generation module, document storage module, document search module, document management module, template document management module and e-mail transmission module. Requirements and design goal of XML/EDI system are introduced, detailed functionalities of modules and design facts are described and execution and execution procedures of the implemented system are explained.

• The KIPS Transactions:PartD
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• v.8D no.2
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• pp.166-174
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• 2001

Lately computing environment is changing into integrating open system. This paper proposes Integrated Management Model to improve productivity about new software development. The model is divided by Management Model to deal with the rapidly changing environment effectively into three layers: the first layer classifies and displays information to users, the users, the second layer controls function, the integration and management layer, and the last layer manages data, the objects management storage layer. So it designs of Efficient Object Management Repository Using Integration Management Model. This might support afterward prototyping in maximizing the reuse of software, which is advantage to the integration of the system, and in promoting its productivity.

• International Journal of Highway Engineering
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• v.16 no.5
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• pp.9-18
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• 2014

PURPOSES : The objective of this study is to evaluate the applicability of the pitch, which is produced during SDA petroleum upgrading process, as a pavement paving material. In order for the purpose, the physical and chemical properties of the pitch are analyzed, and then the various plasticizers are applied in the pitch. METHODS : Two types of pitch are selected from oil refinery companies, which are owned the SDA petroleum upgrading process. Also, two types of asphalt binders, PG 64-22 and PG 58-22, are employed to compare with the pitch because these two types of asphalt binders are currently used as paving materials. For the chemical property of the pitch, the composition of SARA (Saturate, Aromatic, Resin, Asphaltene), the elementary composition, and the functional group are analyzed. For the physical property of the pitch, the basic material property tests, such as penetration test, softening point test, flash point test, ductility test, and rotational viscometer test, are performed. Also, the DSR (Dynamic Shear Rheometer) test and the BBR (Bending Beam Rheometer) test are conducted using asphalt binder specimens obtained by both short term aging (Rolling Thin Film Oven, RTFO) and long term aging (Pressure Aging Vessel, PAV) processes. The rheological property of each pitch type is evaluated as a function of temperatures and loading cycles. PG 64-22 asphalt binder is used as a control material. RESULTS AND CONCLUSIONS : The Pitch may not be suitable for the pavement paving material without modifications, but the pitch can be used as alternatives of modified addictive or asphalt. If low molecular component, such as saturate and aromatic components, are added in the pitch based on the development of various plasticizers, it has a strong possibility for the pitch to be used as a alternative. However, in order to verify the performance property of the pitch, further research is needed.

• Biomedical Science Letters
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• v.22 no.4
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• pp.220-226
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• 2016

Hypertriglyceridemia induces atherosclerosis and accordingly is a major causative factor in cardiovascular diseases. Macrophages that develop into foam cells are a crucial component in the development of atherosclerosis. Monocytes can be differentiated into M1 or M2 macrophages. M1 macrophages promote inflammatory responses, whereas M2 macrophages exhibit anti-inflammatory activity. Recently, we found that triglyceride (TG)-treated THP-1 monocytes express a variety of macrophage-specific surface markers, indicating that TG treatment could trigger the differentiation of monocytes into macrophages. In this study, we investigated whether TG-induced macrophages express the M1 or the M2 macrophage phenotype. THP-1 cells were treated with various concentrations of TG for different times and the expression of M1- and M2-specific markers was evaluated by RT-PCR. We found increased expression of M1 markers (CD40, CD80, and CD86) in TG-treated THP-1 cells in a TG dose- and time-dependent manner. The expression of M2 markers (CD163, CD200R, and CD206) showed variable responses to TG treatment. Taken together, our results indicate that TG treatment triggers the differentiation of monocytes into M1 macrophages, rather than into M2 macrophages, suggesting that TG contributes to pro-inflammatory responses.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.12 no.1
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• pp.123-132
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• 2017

In spite of magnificent growth of The startup education in terms of volumes and varieties, Theoric bases and logics of startup education design are not sufficient and vulnerable. The major reasons of these situations are caused not only by the facts that the startup education has been prepared by the governmental needs but also by the objective in short term period. Considering the fact that the startup educations are also one of classical education itself, it should be adopted the proper education paradigm on its program design. Especially it should be considered of basic education component in startup education design such as education supplier (educator, teacher), education demander (student, educator himself) and education program. In this research, we has reviewed andn proposed efficient design directions and practical strategies for the efficient startup education programs.

• Journal of computational fluids engineering
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• v.21 no.4
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• pp.33-39
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• 2016

Generally, thermal analysis of spent fuel storage cask has been conducted using the porous media and effective thermal conductivity model to simplify the structural complexity of spent fuel assemblies. As the fuel assembly is composed of two regions; active fuel region corresponding to UO2 pellets and unactive fuel region corresponding to the top and bottom nozzle, the heat transfer performance can be influenced depending on porous media application at these regions. In this study, numerical analysis on concrete storage cask of spent fuel was performed to investigate heat transfer effects for two cases; one was porous media application only to active fuel region(case 1) and the other one was porous media to whole length of fuel assembly(case 2). Using computational fluid dynamics code, the three dimensional, 1/4 symmetry model was constructed. For two cases, maximum temperatures for each component were evaluated below the allowable limits. For the case 1, maximum temperatures for fuel cladding, neutron absorber and baskets inside the canister were slightly higher than those for the case 2. In particular, even though the helium flows with low velocity due to buoyant forces occurred at the top and bottom of unactive fuel region, treating only active fuel region as the porous media was ineffective in respect of the heat removal performance of concrete storage cask, implying a conservative result.

• Journal of the Korean Institute of Gas
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• v.4 no.1 s.9
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• pp.63-68
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• 2000

We have developed a new relief valve which is a safety device for the domestic gas-fired hot water boilers. The relief valve has been designed to expand the inner diameter of the inlet, the outlet and the seat of the valve considering the relief capacity, and also to separate the spring from the room heating water. Therefore, we could minimize the adhesion and/or obstruction of the inlet and the corrosion phenomena of the spring which used to be the problem of the conventional relief valves. Test results of the developed relief valve showed that the performance of the opening pressure, reseating pressure, tightness, endurance were excellent, and the operating boiler with developed relief valve was evaluated as very good. The standardization and application of the relief valve can provide the advantage of component exchange and easy maintenance and repair.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.40 no.2
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• pp.167-173
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• 2016

This paper proposes ductile failure simulation under high strain rate conditions using finite element (FE) analyses. In order to simulate a cracked component under a high strain rate condition, this paper applies the stress-modified fracture strain model combined with the Johnson/Cook model. The stress-modified fracture strain model determines the incremental damage in terms of stress triaxiality (${\sigma}_m/{\sigma}_e$) and fracture strain (${\varepsilon}_f$) for a dimple fracture using the tensile test results. To validate the stress-modified fracture strain model under dynamic loading conditions, the parameters are calibrated using the tensile test results under various strain rates and the fracture toughness test results under quasi-static conditions. The calibrated damage model predicts the CT test results under a high strain rate. The simulated results were then compared with the experimental data.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.1
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• pp.17-24
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• 2011

It is reported that an intermittently rotating chamber system will improve the ratio of firepower to armament space in the case of mid-calibre automatic guns. However, the parallel index, which is a main component of the system, tends to be torsionally flexible due to the low lateral stiffness of cam followers on the index turret. This may cause the shaft system connecting the turret with the chamber prone to considerable residual torsional vibration so that serious misalignment problems occur during ammunition loading and firing processes. Herein, an electrorhelogical (ER) fluid actuator that can suppress such vibrations and the associated semiactive control algorithm are proposed. By mathematical modeling and computer simulations, the performance of the entire system is proved satisfactory.