• Nuclear Engineering and Technology
• /
• v.48 no.3
• /
• pp.624-634
• /
• 2016

Nuclear criticality safety analyses (NCSAs) considering burnup credit were performed for the GBC-32 cask. The used nuclear fuel assemblies (UNFAs) discharged from Hanbit Nuclear Power Plant Unit 3 Cycle 6 were loaded into the cask. Their axial burnup distributions and average discharge burnups were evaluated using the DeCART and Multi-purpose Analyzer for Static and Transient Effects of Reactors (MASTER) codes, and NCSAs were performed using SCALE 6.1/STandardized Analysis of Reactivity for Burnup Credit using SCALE (STARBUCS) and Monte Carlo N-Particle transport code, version 6 (MCNP 6). The axial burnup distributions were determined for 20 UNFAs with various initial enrichments and burnups, which were applied to the criticality analysis for the cask system. The UNFAs for 20- and 30-year cooling times were assumed to be stored in the cask. The criticality analyses indicated that $k_{eff}$ values for UNFAs with nonuniform axial burnup distributions were larger than those with a uniform distribution, that is, the end effects were positive but much smaller than those with the reference distribution. The axial burnup distributions for 20 UNFAs had shapes that were more symmetrical with a less steep gradient in the upper region than the reference ones of the United States Department of Energy. These differences in the axial burnup distributions resulted in a significant reduction in end effects compared with the reference.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.40 no.7
• /
• pp.282-292
• /
• 2003

In this paper, we evaluate the performance of WCDMA reverse link receiver system with closed loop fast transmit power control (TPC). For fast power control, SIR must be measured precisely. We propose a new SIR measurement algorithm having a simple structure. The proposed algorithm uses unused OVSF code for interference power evaluation. The proposed SIR measurement algorithm is compared to the conventional SIR measurement algorithm in Ref.$^{［1］}$ under closed loop fast TPC. We adopted WMSA channel estimation filter with Κ=2 for mobile radio channel estimation and considered one slot TPC delay. Extensive computer simulation results show that the proposed algorithm using unused OVSF code reduces the required Ε$_{b}$ /Ι$_{0}$ at the BER of 10$^{-3}$ up to 0.9㏈ and has an improved TPC error performance compared to the conventional algorithm.

• Journal of Korea Multimedia Society
• /
• v.9 no.1
• /
• pp.101-108
• /
• 2006

Developing a network game that is serviced on the internet requires a lot of work, time and manpower. Therefore, it is important to design a game in such a way so that existing design codes could be used. The database for the multi-player network game is accessed from many clients. To manage the resource effectively, it is required to design the APIs to be minimized the database access and to be dealt with the related data efficiently. For this, it is needed to apply the object-oriented design for the related software modules. In the paper, we propose the design patterns of GoF to implement the APIs thatis needed to deal with the database resource. The database design through the analysis of some game's GUI has the advantage to create the optimized schema set more quickly, because it minimize the review step and the modification step of the database design generally. In addition, we apply to the design patterns of GoF for the APIs design of the server-side database. These reduce the times of the program call between the game server and the database server. These also make easily the maintenance for the already developed APIs, and it makes easily the addition of new APIs.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.37 no.6B
• /
• pp.483-488
• /
• 2012

With the fast growing data traffic, the performance of the convergent overlay network environment under the cognitive networking environment is crucial for the implementation of the efficient network structure. In order to achieve high capacity and reliable link quality in wireless communication of the overlay convergent networks with the cognitive networking based on the advanced capability of the mobile terminal, a Distributed Wireless Communication System (DWCS) can provide the capability of ambient-aware dual cell system's operation. This paper has considered virtual cell: the Dual Virtual Cell (DVC), and also proposes DVC employment strategy based on DWCS network. One is the Active Virtual Cell which exists for user's actual data traffic and the other is the Candidate Virtual Cell which contains a set of candidate antennas to protect user's link quality from performance degradation or interruption. The considered system constructs DVC by using cognitive ability of finding useful virtual signals. Also, for multi-user high-rate data transmission, the DWCS system exploits Space-Time Trellis Codes. The effects of changing environments on the system performance has been investigated thereafter.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.33 no.2
• /
• pp.22-31
• /
• 2005

A design study was conducted for a new concept aircraft(Canard Rotor/Wing: CRW) that has the capability of dual mode flight, a rotorcraft and a fixed wing mode. The CRW can show a vertical take off/landing and a high speed/efficiency cruise performance simultaneously. It is not surprising to develop a new sizing code for this class of aircraft because conventional sizing codes developed solely for either the rotary wing or the fixed wing aircraft are not adequate to design a dual mode aircraft operated both by the rotary wing through tip jet effux and the fixed wing lift. Thus, a new design code was developed based on the conventional sizing code by adding some features including rotor performance, duct flow, and engine flow analysis, hence could eventually predict the performance of reaction driven rotor, the flight performance and the flight characteristics. The various design parameters were investigated to find their influences on the flight performance then, a small UAV(Unmanned Aircraft Vehicle) of 1500 lbs class was optimally designed to have minimum weight using the developed sizing code.

• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.96-101
• /
• 2001

Incheon International Airport Construction Project the biggest national multi-complex construction project in a single area in Korea, the necessity for introducing the Program Management System has been brought up from the development stage due to its specific characteristics and environment and with the Project Management Services Contract in December 1994 the system has been established and operated. At the time of contracting, there were controversies over the expected effect of the system since there were no related laws and regulations in domestic construction codes. Furthermore the situation was very hard in which some practical problems have been found in the process of applying and operating the system due to the lack of recognition and infrastructure in Korea. Incheon. In spite of these difficulties, thanks to the devotion and efforts of the project participants along with thoughtful concerns from the industries and the academies, the project goal has been successfully accomplished. This paper will analyze the various problems arose in the process of applying the Project Management System to Incheon International Airport and present more practical and desirable ways so that it can help to make the environment for properly settling Construction Management at the earliest.

• Nuclear Engineering and Technology
• /
• v.50 no.1
• /
• pp.54-67
• /
• 2018

There have been recent efforts to establish methods for high-fidelity and multi-physics simulation with coupled thermal-hydraulic (T/H) and neutronics codes for the entire core of a light water reactor under accident conditions. Considering the computing power necessary for a pin-by-pin analysis of the entire core, subchannel-scale T/H analysis is considered appropriate to achieve acceptable accuracy in an optimal computational time. In the present study, the applicability of in-house code CUPID of the Korea Atomic Energy Research Institute was extended to the subchannel-scale T/H analysis. CUPID is a component-scale T/H analysis code, which uses three-dimensional two-fluid models with various closure models and incorporates a highly parallelized numerical solver. In this study, key models required for a subchannel-scale T/H analysis were implemented in CUPID. Afterward, the code was validated against four subchannel experiments under unheated and heated single-phase incompressible flow conditions. Thereafter, a subchannel-scale T/H analysis of the entire core for an Advanced Power Reactor 1400 reactor core was carried out. For the high-fidelity simulation, detailed geometrical features and individual rod power distributions were considered in this demonstration. In this study, CUPID shows its capability of reproducing key phenomena in a subchannel and dealing with the subchannel-scale whole core T/H analysis.

• Journal of the Institute of Electronics Engineers of Korea CI
• /
• v.46 no.2
• /
• pp.124-133
• /
• 2009

There are many different ID representation forms depending on the media or applications. In case of RFID tag, ID representation form must be followed by the rule of ISO/IEC 15962. In this study, we developed the efficient ID conversion algorithm between ID representation form on RFID tag and Internet. The main idea is on the use of XML based ID profiles and three step logical IDs forms. The algorithm was tested by the typical three kinds of real IDs such as EPC, ISO/IEC 15459 KKR Code, and mCode which are the typical meta-IDs can be defined in ISO/IEC 18000-6C tag.

• Journal of Korea Game Society
• /
• v.14 no.5
• /
• pp.15-24
• /
• 2014

Semiotics studies the structures and systems of all signs related to human life, thus being capable of analyzing games. "Playing games" can be deemed as an act of reading or interpreting games semiotically, which makes game producers "senders," games "texts," gamers "receivers," and gamers playing games "contexts." Since most games are in the multi-variable narrative format, however, it is not a frequent case that gamers interpret games in the ways intended by producers. This study thus set out to analyze and interpret the console game (2001) remembered as the same evaluation by many gamers in the way intended by the producer. For analysis, the study defined its story program by analyzing the plot and sequence. For semantic analysis, the study applied the Actor Model and the Semiotic Square Model to interpret . The process identified such codes as confrontation, assistance, collaboration, and control and confirmed that Ico and Yorda, non-subject characters, were transforming into subject ones. That is, tells a story of the main characters that used to lead a non-subject life earning lives of their own.

• The Journal of Korean Institute of Communications and Information Sciences
• /
• v.29 no.4C
• /
• pp.485-493
• /
• 2004

The system performance of 2-Dimensional wavelength hopping/time spreading optical CDMA systems is found to be limited by the occurrence of the beat noise between the components of the signal and the multiple user interference. This paper shows that the performance is analyzed under the beat noise and no beat noise to blow impact of the beat noise. To overcome this problem, the OHL(Optical Hard-Limiter) is used in the receiver. The performance is calculated for a optical CDMA system employing asymmetric and symmetric prime-hop 2-Dimensional codes, respectively The analysis results show that the performance improved 3.5 times of simultaneous users of before and after inserting OHL in the case of no beat noise. In the case of beat noise the performance improved 1.5 times of simultaneous users of before and after inserting OHL. The performance marked use of symmetric prime-hop code.