• Journal of the Korean Society of Safety
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• v.35 no.4
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• pp.84-91
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• 2020

The Korean nuclear industry developed the SPACE (Safety and Performance Analysis Code for nuclear power plants) code and this code adpots two-phase flows, two-fluid, three-field models which are comprised of gas, continuous liquid and droplet fields and has a capability to simulate three-dimensional model. According to the revised law by the Nuclear Safety and Security Commission (NSSC) in Korea, the multiple failure accidents that must be considered for accident management plan of nuclear power plant was determined based on the lessons learned from the Fukushima accident. Generally, to improve the reliability of the calculation results of a safety analysis code, verification work for separate and integral effect experiments is required. In this reason, the goal of this work is to verify calculation capability of SPACE code for multiple failure accident. For this purpose, it was selected the experiment which was conducted to simulate a Multiple Steam Generator Tube Rupture(MSGTR) accident with Passive Auxiliary Feedwater System(PAFS) operation by Korea Atomic Energy Research Institute (KAERI) and focused that the comparison between the experiment results and code calculation results to verify the performance of the SPACE code. The MSGR accident has a unique feature of the penetration of the barrier between the Reactor Coolant System (RCS) and the secondary system resulting from multiple failure of steam generator U-tubes. The PAFS is one of the advanced safety features with passive cooling system to replace a conventional active auxiliary feedwater system. This system is passively capable of condensing steam generated in steam generator and feeding the condensed water to the steam generator by gravity. As the results of overall system transient response using SPACE code showed similar trends with the experimental results such as the system pressure, mass flow rate, and collapsed water level in component. In conclusion, it could be concluded that the SPACE code has sufficient capability to simulate a MSGTR accident.

• Journal of the Korean Institute of Telematics and Electronics
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• v.27 no.8
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• pp.1221-1230
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• 1990

This paper presents a code generation method and an effective handling algorithm of ingeger constant multiplication for RISC machines in compiler design. As RISC Architectures usually use faster and more simply formed instructions than CISC's and most RISC processors do not have an integer multiplication instruction, it is required an effective algorithm to process integer multiplication. For the proposed code generator, Portable C Compiler(PCC) is redesigned to be suitable for an RISC machine, and composed an addition chain is built up to allow fast execution of constant multiplication, a part of integer one whicch appears very frequency in code generation phase.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.1 no.2
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• pp.193-197
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• 1997

In this paper, we propose a new PN chip clock generator which employs two synchronous counters to achieve precise phase control of chip clock. In a CDMA code acquisition and tracking system, the PN chip clock is required to operate highly reliable without any glitch even under harsh environment condition such as temperature and voltage fluctu-aliens. The digital implementation of the proposed PN chip clock generator imparts it with much desired reliability. Since the proposed chip clock generator can be easily controlled into one of the states: free running, phase advance, and delay state, it can be applied to data processing as well as code synchronization. We have done FPGA implementation of the proposed logic and have verified its satisfactory operation up to 50 MHz.

• The KIPS Transactions:PartA
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• v.14A no.1 s.105
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• pp.31-38
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• 2007

Code Optimization is converting to a code that is equivalent to given program but more efficient, and this process is processed in Code Optimizer. This paper designed and processed Code Optimizer Generator that automatically generates Code Optimizer. In other words Code Optimizer is automatically generated for DFA Pattern Matching which finds the optimal code for the incoming pattern description. DFA Pattern Matching removes redundancy comparisons that occur when patterns are sought for through normalization process and improves simplification and structure of pattern shapes for low cost. Automatic generation of Code Optimization for DFA Pattern Matching eliminates extra effort to generate Code Optimizer every time the code undergoes various transformations, and enables formalism of Code Optimization. Also, the advantage of making DFA for optimization is that it is faster and saves cost of Code Optimizer Generator.

• Korean Management Science Review
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• v.11 no.1
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• pp.1-21
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• 1994

We usually use the simulation technique in the evaluation and the test of a design alternative of Automated Guided Vehicle System. In this paper, we introduce a simulation code generator which can assist simulation programmer in model development and programming. It consists of user interface, program editor, and program sorter. SIMAN is used as the target language.

• 제어로봇시스템학회:학술대회논문집
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• 2003.10a
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• pp.2632-2635
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• 2003

This paper designs a software signal generator for the new GPS L2 civil signal. The CM/CL code and the message structure of L2CS described in GPS ICD PPIRN-200C-007 are used in designing the signal generator. The output of the GPS signal generator is designed as the sampled IF data with the sampling frequency 5.7MHz and stored in the binary data format. By analyzing both the spectrum characteristics of the output signal and the correlation properties of the CM/CL code, the validation of the designed GPS signal generator is shown. It should be mentioned that the modeling of the GPS satellite constellation and the error sources remains for implementing the software space segment of GPS.

• Journal of computational fluids engineering
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• v.7 no.2
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• pp.43-52
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• 2002

This paper presents the numerical methodology of ATHOS3 code for thermal hydraulic analysis of steam generators in nuclear power plant. Topics include porous media approach, governing equations, physical models and correlations for solid-to-fluid interaction and heat transfer, and numerical solution scheme. The ATHOS3 code is applied to the thermal hydraulic analysis of steam generator in the Korea Kori Unit-1 nuclear power plant and the computed results are presented

• Nuclear Engineering and Technology
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• v.49 no.7
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• pp.1388-1395
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• 2017

The Helically coiled tube Once-Through Steam Generator (H-OTSG) is a key piece of equipment for compact small reactors. The present study developed and verified a thermal-hydraulic design and performance analysis computer code for a countercurrent H-OTSG installed in a small pressurized water reactor. The H-OTSG is represented by one characteristic tube in the model. The secondary side of the H-OTSG is divided into single-phase liquid region, nucleate boiling region, postdryout region, and single-phase vapor region. Different heat transfer correlations and pressure drop correlations are reviewed and applied. To benchmark the developed physical models and the computer code, H-OTSGs developed in Marine Reactor X and System-integrated Modular Advanced ReacTor are simulated by the code, and the results are compared with the design data. The overall characteristics of heat transfer area, temperature distributions, and pressure drops calculated by the code showed general agreement with the published data. The thermal-hydraulic characteristics of a typical countercurrent H-OTSG are analyzed. It is demonstrated that the code can be utilized for design and performance analysis of an H-OTSG.

• Journal of the Institute of Convergence Signal Processing
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• v.6 no.4
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• pp.206-211
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• 2005

We describe the design for a correlator and an access code generator in bluetooth system. These are used for a connection setting, a packet decision and a clock synchronization between Bluetooth units. The correlator consists of two blocks; carry save adder based on Wallace tree and threshold-value decision block. It determines on an useful packet and clock-synchronization for input signal of 1.0Mbps through the sliding-window correlating. The access-code generator also consists of two blocks; BCH(Bose-Chadhuri-Hocquenghem) cyclic encoder and control block. It generates the access-codes according to four steps' generation process based on Bluetooth standard. In order to solve synchronization problem, we make use of any memory as a pseudo random sequence. The proposed correlator and access-code generator were coded with VHDL. An FPGA Implementation of these modules and the simulation results are proved by Xilinx chip. The critical delay and correlative margin based on synthesis show the 4.689ns and the allowable correlation-error up to 7-bit.

• Journal of the Korea Society for Simulation
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• v.5 no.1
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• pp.67-79
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• 1996

This paper proposes an intelligent simulation generator, called INSIMS, for manufacturing systems. The INSIMS provides an interactive dialogue interactive dialogue interface and code generation tools for modeling and code genration of manufacturing systems. The interactive dialogue interface helps non-expert simulation modeler specify manufacturing systems with ease. After completing the model construction processes, the modeling specifications are automatically converted into SLAM II codes by code generation tools. To validate the usefulness of INSIMS and to illustrate the modeling processes, an example system has been presented.