• Nuclear Engineering and Technology
• /
• v.27 no.1
• /
• pp.84-95
• /
• 1995

Application of computer software to safety-critical systems is on the increase. To be successful, the software must be designed and constructed to meet the functional and performance requirements of the system. For safety reason, the software must be demonstrated not only to meet these requirements, but also to operate safely as a component within the system. For longer-term cost consideration, the software must be designed and structured to ease future maintenance and modifications. This paper present a software engineering process for the production of safety-critical software for a nuclear power plant The presentation is expository in nature of a viable high quality safety-critical software development. It is based on the ideas of a rational design process and on the experience of the adaptation of such process in the production of the safety-critical software for the Shutdown System Number Two of Wolsong 2, 3 & 4 nuclear power generation plants. This process is significantly different from a conventional process in terms of rigorous software development phases and software design techniques. The process covers documentation, design, verification and testing using mathematically precise notations and highly reviewable tabular format to specify software requirements and software design. These specifications allow rigorous, stepwise verification of software design against software requirements, and code against software design using static analysis. The software engineering process described in this paper applies the principle of information-hiding decomposition in software design using a modular design technique so that when a change is' required or an error is detected, the affected scope can be readily and confidently located. It also facilitates a sense of high degree of confidence in the ‘correctness’ of the software production, and provides a relatively simple and straightforward code implementation effort.

• Atmosphere
• /
• v.26 no.1
• /
• pp.1-18
• /
• 2016

Eleven Tropical Cyclone (TC) intensity guidance models in the western North Pacific have been validated over 2008~2014 based on various analysis methods according to the lead time of forecast, year, month, intensity, rapid intensity change, track, and geographical area with an additional focus on TCs that influenced the Korean peninsula. From the evaluation using mean absolute error and correlation coefficients for maximum wind speed forecasts up to 72 h, we found that the Hurricane Weather Research and Forecasting model (HWRF) outperforms all others overall although the Global Forecast System (GFS), the Typhoon Ensemble Prediction System of Japan Meteorological Agency (TEPS), and the Korean version of Weather and Weather Research and Forecasting model (KWRF) also shows a good performance in some lead times of forecast. In particular, HWRF shows the highest performance in predicting the intensity of strong TCs above Category 3, which may be attributed to its highest spatial resolution (~3 km). The Navy Operational Global Prediction Model (NOGAPS) and GFS were the most improved model during 2008~2014. For initial intensity error, two Japanese models, Japan Meteorological Agency Global Spectral Model (JGSM) and TEPS, had the smallest error. In track forecast, the European Centre for Medium-Range Weather Forecasts (ECMWF) and recent GFS model outperformed others. The present results has significant implications for providing basic information for operational forecasters as well as developing ensemble or consensus prediction systems.

• The Journal of Korean Medicine
• /
• v.38 no.3
• /
• pp.73-85
• /
• 2017

Objectives: The purpose of this study was to investigate the status of Korean medicine treatment, and to analyze problems and demands to provide basic data on Korean medicine in military medical services. Methods: This survey was completed by 30 volunteer Korean medicine military doctors on service via a web-based questionnaire system. The questionnaire was developed through in-depth interviews with Korean medicine military doctors and consisted of general information on the subject, overall characteristics of the medical environment, current status of Korean medicine care in each workplace, problems and needs, and related clinical evidence and education. Results: Korean medicine military doctors administered acupuncture treatment most frequently in clinical practice. The most common complaints were related to musculoskeletal diseases, which accounted for 86.5% of all diseases, including those of the respiratory, digestive, and nervous systems. Most of the problems in Korean medicine care were pointed out as being due to a lack of awareness of Korean medicine in the military. Many doctors were aware that it is necessary to establish clinical evidence for Korean medicine in the military, and were also positive about the possibility of performing clinical research in the military, but the experience of actual participation in clinical research or related education was uncommon. Conclusions: Korean medicine military treatment differs from private medical care due to the specificity of each workplace and the military medical system. In the future, it will be necessary to establish an appropriate Korean medicine treatment model in the military suitable for these characteristics and strategic plans for clinical evidence.

• Composites Research
• /
• v.28 no.6
• /
• pp.372-377
• /
• 2015

In this study, we analyzed process numerically when a bogie frame skin is manufactured by applying resin transfer molding process using composite material instead of steel. Processing time was compared based on the various thickness of bogie frame skin and the weight variation of a skin was also considered. As a result, RTM processing time decreases and the weight of a bogie reduces as the thickness of frame skin increases with the assumption that fiber volume is constant inside the skin. By considering these results as the information to estimate the production cost, trade-off between two fields, processing time and structural properties, can be performed in design optimization to produce bogie frame.

• Biomedical Science Letters
• /
• v.22 no.3
• /
• pp.75-82
• /
• 2016

The immune system and neuroendocrine systems are the two key components that maintain bodily homeostasis. Peripheral blood specimens can indicate abnormalities in a body, which often cause various threats to human health, including devastating autoimmune or metabolic diseases. To develop a treatment regimen for such diseases, experimental animal models are indispensable to researchers in academic fields. In this study, we examined the peripheral blood of 3 representative mouse strains (ICR, Balb/c, and C57Bl/6), which are widely used, to investigate whether there is a difference in reference range according to animal model. We performed hematological and chemistry analysis on individuals of both genders. The results of hematology analysis showed that the number of most types of blood cells was lower in ICR than in the other two strains. The results of chemical analysis revealed no specific pattern, but different patterns according to the individual indicator. Although the distinction between ICR and B6 was prominent, differences between Balb/c and B6 were also observed for several indicators. For some indicators, totally different patterns existed between females and males. Conclusively, this study provides the information that 3 experimentally representative mouse models have their own basal levels of blood components, suggesting the importance of a careful choice of a proper mouse model in research into immune or metabolic diseases, to exclude any biases.

• Journal of Navigation and Port Research
• /
• v.29 no.5 s.101
• /
• pp.457-464
• /
• 2005

Database integration has been recognized as a critical issue for effective logistics service in logistics environment. However, research related to effective methodology for this have been little studied, and also, prominent achievements have yet to be suggested. The aim of this paper is to present a quantitative methodology for the identification of conflict that is a representative problem on database integration. To achieve this aim, we suggested a quantitative methodology that can efficiently fine troubles such as name conflicts when schema integration, based on the level of semantic similarity between attributes and entities. And, in order to measure these semantic similarities, we used a thesaurus dictionary that proposed previous research. Finally, we presented effectiveness of the proposed methodology through some typical examples.

• Nuclear Engineering and Technology
• /
• v.52 no.5
• /
• pp.1013-1021
• /
• 2020

A combination of simultaneous thermal analysis, evolved gas analysis and non-ambient XRD techniques was used to characterise and investigate the conversion reactions of ammonium uranates into uranium oxides. Two solid phases of the ternary system NH₃ - UO₃ - H₂O were synthesised under specified conditions. Microspheres prepared by the sol-gel method via internal gelation were identified as 3UO₃·2NH₃·4H₂O, whereas the product of a typical ammonium diuranate precipitation reaction was associated to the composition 3UO₃·NH₃·5H₂O. The thermal decomposition profile of both compounds in air feature distinct reaction steps towards the conversion to U₃O₈, owing to the successive release of water and ammonia molecules. Both compounds are converted into α-U₃O₈ above 550 ℃, but the crystallographic transition occurs differently. In compound 3UO₃·NH₃·5H₂O (ADU) the transformation occurs via the crystalline β-UO₃ phase, whereas in compound 3UO₃·2NH₃·4H₂O (microspheres) an amorphous UO₃ intermediate was observed. The new insights obtained on these uranate systems improve the information base for designing and synthesising minor actinide-containing target materials in future applications.

• International Journal of Naval Architecture and Ocean Engineering
• /
• v.11 no.1
• /
• pp.82-96
• /
• 2019

A semi-submersible structure has been widely used for offshore drilling and production of oil and gas. The small water plane area makes the structure very sensitive to weight increase in terms of payload and stability. Therefore, it is necessary to lighten the substructure from the early design stage. This study aims at an optimization of hull structure based on a sophisticated yield and buckling strength in accordance with classification rules. An in-house strength assessment system is developed to automate the procedure such as a generation of buckling panels, a collection of required panel information, automatic buckling and yield check and so on. The developed system enables an automatic yield and buckling strength check of all panels composing the hull structure at each iteration of the optimization. Design variables are plate thickness and stiffener section profiles. In order to overcome the difficulty of large number of design variables and the computational burden of FE analysis, various methods are proposed. The steepest descent method is selected as the optimization algorithm for an efficient search. For a reduction of the number of design variables and a direct application to practical design, the stiffener section variable is determined by selecting one from a pre-defined standard library. Plate thickness is also discretized at 0.5t interval. The number of FE analysis is reduced by using equations to analytically estimating the stress changes in gradient calculation and line search steps. As an endeavor to robust optimization, the number of design variables to be simultaneously optimized is divided by grouping the scantling variables by the plane. A sequential optimization is performed group by group. As a verification example, a central column of a semi-submersible structure is optimized and compared with a conventional optimization of all design variables at once.

• Knowledge Management Research
• /
• v.23 no.2
• /
• pp.1-13
• /
• 2022

Metaverse has been encountering in our daily lives, and it has dynamically changed people's way of working, educating, and entertaining. During the Covid-19, people has been more immersed with virtual world. For example, the virtual environments have created new form and features of our remote work, online education, entertainment, and so on. Also, some people make a strong tie with their avatar to live in a virtual world. Indeed, it became a new normal life now. With this radical social and technological change, the metaverse has become a core issue for the communities of researchers and practitioners as well, and a variety of meaningful research and products have been conducted so far. Nevertheless, it still is lack of diverse theoretical, empirical, and practical studies, dealing with this huge socio-technical shift with the metaverse. Therefore, in this special issue commentary, we suggest potential metaverse research issues and topics, which highlight how management, organization, and information systems researchers could dance with the ongoing metaverse ecosystem for creating more productive research performances.

• Journal of Cadastre & Land InformatiX
• /
• v.53 no.1
• /
• pp.21-36
• /
• 2023

Activity-based modeling systems have increasingly been developed to address the limitations of widely used traditional four-step transportation demand forecasting models. Accordingly, this paper introduces the Activity-BAsed Traveler Analyzer (ABATA) system. This system consists of multiple components, including an hourly total population estimator, activity profile constructor, hourly activity population estimator, spatial activity population estimator, and origin/destination estimator. To demonstrate the proposed system, the emission impact of land use changes in the 5-1 block Sejong smart city is evaluated as a case study. The results indicate that the land use with the scenario of work facility dispersed plan produced more emissions than the scenario of work facility centralized plan due to the longer travel distance. The proposed ABATA system is expected to provide a valuable tool for simulating the impacts of future changes in population, activity schedules, and land use on activity populations and travel demands.