• Transactions of the Korean Society of Pressure Vessels and Piping
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• v.12 no.1
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• pp.56-61
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• 2016

After Japanese Fukushima nuclear power plant accident caused by the beyond design basis earthquake and tsunami, it has turned to be a major challenge for nuclear safety. IAEA, US NRC and EU have provided new safety design standards for beyond design basis event, Domestic regulatory bodies have also enacted guidances for licensees and applicants on additional methods related to beyond design basis events. This paper describes several evaluation methods for applying to nuclear power plants piping for beyond design basis earthquake. As a results, energy method based on the absorbed energy on nuclear power plant, deterministic method following design code and theory, experience method considering past earthquake data and information and probabilistic methods similar to probabilistic risk assessment were reviewed.

• Nuclear Engineering and Technology
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• v.44 no.3
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• pp.225-236
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• 2012

The Fukushima-Daiichi accident shook the world, as a well-known plant design, the General Electric BWR Mark I, was heavily damaged in the tsunami, which followed the Great Japanese Earthquake of 11 March 2011. Plant safety functions were lost and, as both AC and DC failed, manoeuvrability of the plants at the site virtually came to a full stop. The traditional system of Emergency Operating Procedures (EOPs) and Severe Accident Management Guidelines (SAMG) failed to protect core and containment, and severe core damage resulted, followed by devastating hydrogen explosions and, finally, considerable radioactive releases. The root cause may not only have been that the design against tsunamis was incorrect, but that the defence against accidents in most power plants is based on traditional assumptions, such as Large Break LOCA as the limiting event, whereas there is no engineered design against severe accidents in most plants. Accidents beyond the licensed design basis have hardly been considered in the various designs, and if they were included, they often were not classified for their safety role, as most system safety classifications considered only design basis accidents. It is, hence, time to again consider the Design Basis Accident, and ask ourselves whether the time has not come to consider engineered safety functions to mitigate core damage accidents. Associated is a proper classification of those systems that do the job. Also associated are safety criteria, which so far are only related to 'public health and safety'; in reality, nuclear accidents cause few casualties, but create immense economical and societal effects-for which there are no criteria to be met. Severe accidents create an environment far surpassing the imagination of those who developed EOPs and SAMG, most of which was developed after Three Mile Island - an accident where all was still in place, except the insight in the event was lost. It requires fundamental changes in our present safety approach and safety thinking and, hence, also in our EOPs and SAMG, in order to prevent future 'Fukushimas'.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_1
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• pp.549-557
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• 2012

Spatial phenomena such as environment pollution, disease and the risk of spreading information need a rapid initial response to perceive spread event. Moving data perceive spread event through real-time processing and analysis. To process and analysis the event, spatial-temporal complex event processing is used. Previous spatialtemporal complex event processing is possible basis spatial operator but insufficient apply to design spatialtemporal complex event processing to perceive spatial phenomena of high complexity. This study proposed hierarchical spatio-temporal CEP design which will efficiently manage the fast growing incoming sensor data. The implementation of the proposed design is evaluated with GPS location data of moving vehicles which are used as the incoming data stream for identifying spatial events. The spatial component of existing CEP software engine has been extended during the implementation phase to broaden the capabilities of processing spatio-temporal events.

• Journal of the Korea Society for Simulation
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• v.3 no.1
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• pp.75-88
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• 1994

Discrete event modeling is finding ever more application to anlysis and design of complex manufacturing, communication, computer systems, etc. This paper shows how packet network systems may be advantageously represented as DEVS (Discrete Event System Specification) models by employing System Entity structure / Model base (SES/MB) framework developed by Zeigler. DEVS models and network structure representations support a strong basis for performance analysis of packet network systems. This approach is illustated in a typical packet network example with several routing strategies.

• Nuclear Engineering and Technology
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• v.50 no.6
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• pp.860-868
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• 2018

This article presents a new design of earthquake instrumentation that is suitable for quick decision-making after the seismic event at the nuclear power plant (NPP). The main objective of this work is to ensure more availability of the NPP by expediting walk-down period when the seismic wave is incident. In general, the decision-making to restart the NPP after the seismic event requires more than 1 month if an earthquake exceeds operating basis earthquake level. It affects to the plant availability significantly. Unnecessary shutdown can be skipped through quick assessments of operating basis earthquake, safe shutdown earthquake events, and damage status to structure, system, and components. Multidecision parameters such as cumulative absolute velocity, peak ground acceleration, Modified Mercalli Intensity Scale, floor response spectrum, and cumulative fatigue are discussed. The implementation scope on the field-programmable gate array platform of this work is limited to cumulative absolute velocity, peak ground acceleration, and Modified Mercalli Intensity. It can ensure better availability of the plant through integrated decision-making process by automatic assessment of NPP structure, system, and components.

• Proceedings of the Korean Institute of Interior Design Conference
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• 2007.11a
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• pp.179-182
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• 2007

2007 Design Festival on Seongnam Living Design has been held with the theme of "You and I, We" on the basis of harmony through design. This kind of theme has the main concepts as follows: Harmony- the exhibition program that can capture our mind, Communication-the experience program not through personal work but through group work, Design Seongnam-joyful Sungnam which we have made together by regional participation design project. Especially, it also has encouraged active and voluntary participation based on the promotion of the event and design exhibition that are hosted by the universities, elementary and secondary schools that represent the downtown Seongnam. In understanding Seongnam City, it has applied the plan introducing emotional process. These are the programs, which are reading, thinking, listening, watching, touching, making, and dreaming. Through the processes of being with Seongnam by participants, it has helped people know more about Seongnam, and focused on being the exhibition understanding the members of the community Seongnam.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.64 no.6
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• pp.922-934
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• 2015

In this paper, The classification between precipitation echo(PRE) and non-precipitation echo(N-PRE) (including ground echo and clear echo) is carried out from weather radar data using neuro-fuzzy algorithm. In order to classify between PRE and N-PRE, Input variables are built up through characteristic analysis of radar data. First, the event classifier as the first classification step is designed to classify precipitation event and non-precipitation event using input variables of RBFNNs such as DZ, DZ of Frequency(DZ_FR), SDZ, SDZ of Frequency(SDZ_FR), VGZ, VGZ of Frequency(VGZ_FR). After the event classification, in the precipitation event including non-precipitation echo, the non-precipitation echo is completely removed by the echo classifier of the second classifier step that is built as Type-2 FCM based RBFNNs. Also, parameters of classification system are acquired for effective performance using PSO(Particle Swarm Optimization). The performance results of the proposed echo classifier are compared with CZ. In the sequel, the proposed model architectures which use event classifier as well as the echo classifier of Interval Type-2 FCM based RBFNN show the superiority of output performance when compared with the conventional echo classifier based on RBFNN.

• Journal of the Korean Society of Costume
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• v.56 no.8 s.108
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• pp.148-159
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• 2006

The objective of this study is to consider the uniform as visual communication, and analyze the expression of symbol shown on the uniform design by the pattern by applying the visual symbol in the communication and operation of the meaning. Also, it is to construct the systematic modeling method of the expression of design symbol by the pattern of uniform in th e various fields. This study is to analyze the symbolic expression method of the uniform design by the pattern by suggesting the symbolic expression method as a frame through the visual symbolic approach of the uniform design and the analysis of semantic symbol according to that. As a result, there arose simplification and emphasis and a method of symbolic expression with the national flag, a conceptual factor characteristically in the sports uniform design. The characteristics of symbolic expression of uniform design were mainly used in the symbolic expression with the customary code and symbol. Also, the uniform in the enterprises were widely used in the expression of uniform with the suggestion and code by the color. As for the characteristics of symbolic expression shown on the event uniform design, the method of symbolic expression by the pattern of uniform was grasped differently asa result of symbolic expression through the image. The method of symbolic expression suggested on this study could be used on a basis of uniform design in the future. Accordingly, this study has a meaning of suggesting the methodology of uniform design that would be a parameter.

• Archives of design research
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• v.14
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• pp.121-138
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• 1996

The purpose of this study is to develop a new architectural language and design strategies that would anticipate and incorporate new historical situations and new paradigms to understand the world. It consists of four sections as follows: First, it presents a new interpretation of space, human body, and movement that we find in modern art and tries to combine that new artistic insight with environmental design to provide a theoretical basis for performance-event architecture. Second, it conceives of architectural environment as a combination of space, movement, and probabilistic situations rather than a mere conglomeration of material. It also perceives the environment as a stage for performance and the act of designing as a performance. Third, in this context, man is conceived of as an organic system that responds to, interacts with, and adapts himself to his environment through self-regulation. By the same token, architecture should be a dynamic system that undergoes a constant transformation in its attempt to accommodate human actions and behaviors as he copes with the contemporary philosophy characterized by the principle of uncertainty, fast-changing society, and the new developments in technology. Fourth, the relativistic and organic view-point that constitutes the background for all this is radically different from the causalistic and mechanistic view that characterized the forms and functions of modernistic design. The present study places a great emphases on dematerialistic conception of environment and puts forth a disprogramming method that would accommodate interchangeability in the passage of time and the intertextuality of form and function. In the event, performance-event architecture is a strategy based on the systems world-view that would enable the recovery of man's autonomy and the reconception of his environment as an object of art.

• The Transactions of the Korean Institute of Power Electronics
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• v.24 no.3
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• pp.207-214
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• 2019

In this study, discrete-time domain analysis is proposed to investigate the input current of a buck AC/DC light-emitting diode (LED) driver. The buck power factor correction converter can operate in both discontinuous conduction mode (DCM) and continuous conduction mode (CCM). Two discontinuous and two continuous conduction operating modes are possible depending on which event terminates the conduction of the main switch in a switching cycle. All four operating modes are considered in the discrete-time domain analysis. The peak current-mode control with slope compensation is used to design a low-cost AC/DC LED driver. A slope compensation design of the buck AC/DC LED driver is described on the basis of a discrete-time domain analysis. Experimental results are presented to confirm the usefulness of the proposed analysis.