• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.19 no.8
• /
• pp.545-551
• /
• 2018

For domestic application of the temperature gradient model proposed by foreign design standards, a specimen of steel box girder bridge was fabricated with the following dimensions: 2.0 m width, 2.0 m height and 3.0 m length. Temperature was measured using 24 temperature gauges during the summer of 2016. The reliability of the measured data was verified by comparing the measured air temperature with the ambient air temperature of the Korea Meteorological Administration. Of the measured gauges, four temperature gauges that can be compared with the temperature difference of the Euro code were selected and used to analyze the distribution of the measured temperatures at each point. The reference atmospheric temperature for the selection of the maximum temperature difference was determined by considering the standard error. Maximum and minimum temperatures were calculated from the four selected points and the resulting temperature difference was calculated. The model for the temperature difference in the steel box girder bridge was shown by graphing the temperature difference. Compared to the temperature distribution of the Euro code, the presented temperature difference model showed a temperature difference of $0.9^{\circ}C$ at the top and of $0.3^{\circ}$ to $0.4^{\circ}C$ at the intermediate part. These results suggested that the presented model could be considered relatively similar to the Euro code The calculated standard error coefficient was 2.71 to 2.84 times the standard error and represents a range of values. The proposed temperature difference model may be used to generate basic data for calculating the temperature difference in temperature load design.

• Journal of Advanced Marine Engineering and Technology
• /
• v.22 no.3
• /
• pp.275-284
• /
• 1998

Standard on the carbon dioxide extinguishing system was prepared by the committed of the national fire protection assocition(NFPA)in USA on 1980. And this code is also applied to the design of a marine fire extinguishing system The most important problem in design is the uniform discharge of $CO_2$ through each nozzle from the high pressure $CO_2$ storage facility. The purpose of this paper is to develop the computer software to design the marine fire protection piping system. By solving the continuity equation energy equation and Bernoulli's equation simulataneously the flowrate in branch pipelines and discharge nozzles can be calculated.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1999.04a
• /
• pp.209-214
• /
• 1999

Strength provisions in Korea Concrete Institute code are more conservative that those in ACI code by increasing load factors and decreasing capacity reduction factors. Cement content of mix design in construction field is usually higher than the modified for standard deviation because of rigorous inspection. Higher cement content increases not only strengths but also heat of hydration, shrinkage and brittleness which are not beneficial. To reduce and optimize the cement content in current mix design of Korean Highway Corporation, properties of fresh and hardened concrete for 16 different mix proportions have been investigated. It is found that the chemical admixture and cement of current mix proportions for highway construction are somewhat higher than the optimum amount. Therefore, the optimum mix design for 16 different purposes has been proposed.

• Journal of the Korean Society of Marine Environment & Safety
• /
• v.9 no.2
• /
• pp.47-52
• /
• 2003

This study conducted a basic study to develop ISM Code operation evaluation module, which is part of development of Safety Management System(ISM Code) Implementation supporting module. In particular, the significant of this study is that it established AHP operation evaluation analysis process, the design of questionnaire, and the hierarchical structure of operation evaluation model standard, focusing on the development of ISM Code operation evaluation module. Also, this study has its value in the point that it attempted to apply AHP scheme, which is part of the main decision­making in management science field, to develop operation evaluation module.

• Journal of IKEEE
• /
• v.12 no.2
• /
• pp.95-101
• /
• 2008

In this paper, we study an optimum design of search synchronization structure for Baseband Modem to support ISO/IEC 18185-5 and 24730-2 Standard. For DSSS Modem, we design the code acquisition and tracking structure which are important in receiver operation, and examine the parameters to be considered. The data and PN chip transmission rates and processing gain of the proposed modem are 59.7 kbps, 30.521875 Mcps, and 27 dB, respectively. This indicates that the noise immunity of the proposed modem is 17dB better than IEEE 802.11b (Processing gain : 10dB). Therefore, we design the optimum structure for the modem search synchronization which is compatible to the proposed modem standard.

• Journal of The Korean Association of Information Education
• /
• v.2 no.1
• /
• pp.138-161
• /
• 1998

This research addresses to establish a systematic approach to design a standard Hangul code system for educational purposes in development of CAI courseware using Korean, English, and Chinese characters, which requires data exchanges and database construction. In this paper, types of Korean alphabetic code systems already in use, their representational environments and consonant/vowel order have been studied and analysed. This paper presents the requirements that the hangul code system for educational purpose needs to obtain. First, it should be able to represent all contemporary as well as ancient Korean alphabets. Second, character elements should be separable. Third, consonant/vowel order should be determined to easily retrieve and exchange data. Lastly, the code should maintain compatibility with other national codes and provide uniqueness of user-defined character codes.

• Journal of the Korean Society for Precision Engineering
• /
• v.20 no.11
• /
• pp.117-126
• /
• 2003

GA(genetic algorithm) has a powerful searching ability and is comparatively easy to use and to apply as well. By that reason, GA is in the spotlight these days as an optimization skill for mechanical systems.$^1$However, GA has a low efficiency caused by a huge amount of repetitive computation and an inefficiency that GA meanders near the optimum. It also can be shown a phenomenon such as genetic drifting which converges to a wrong solution.$^{8}$ These defects are the reasons why GA is not widdy applied to real world problems. However, the low efficiency problem and the meandering problem of GA can be overcomed by introducing parallel computation$^{7}$ and gray code$^4$, respectively. Standard GA(SGA)$^{9}$ works fine on small to medium scale problems. However, SGA done not work well for large-scale problems. Large-scale problems with more than 500-bit of sere's have never been tested and published in papers. In the result of using the SGA, the powerful searching ability of SGA doesn't have no effect on optimizing the problem that has 96 design valuables and 1536 bits of gene's length. So it converges to a solution which is not considered as a global optimum. Therefore, this study proposes ExpGA(experience GA) which is a new genetic algorithm made by applying a new probability parameter called by the experience value. Furthermore, this study finds the solution throughout the whole field searching, with applying ExpGA which is a optimization technique for the structure having genetic drifting by the standard GA and not making a optimization close to the best fitted value. In addition to them, this study also makes a research about the possibility of GA as a optimization technique of large-scale design variable problems.

• Journal of KIISE:Computing Practices and Letters
• /
• v.15 no.2
• /
• pp.140-144
• /
• 2009

The efficient test tool is indispensable to the test driven development. The test tool is very helpful to get the advantage of the test driven development. Many traditional automation test tool does not support standard script language and are not suitable to unit test. In traditional unit test tool, a code for the test is added at the source code. Such method makes the complexity of a source code and has a problem which must modify many part of the source code when the test case is changed. In this paper, we present a design technique of a flexible unit testing tool which makes a developer can modify easily the test case by using the standard java script in test driven development. We implement the test tool by this design technique to verify the availability of this technique.

• Proceedings of the Korea Concrete Institute Conference
• /
• 1996.04a
• /
• pp.289-294
• /
• 1996

This paper persents the assessment of the minimum shear reinforcement requirements in normal, medium and high-strength reinforced concrete beams. Twelve shear tests were conducted on full-scale beam specimens having design concrete compressive strengths of 35, 70 and 100 MPa. Different amounts of minimum shear reinfrocement were investigated, including the amounts required by Korean Concrete Standard (KCI88), JCI86, ACI89 (revised 1992) and CSA94 standard. The performance of the different amounts of shear reinforcement are discussed in terms of the shear capacity, the ductility and the crack control at service load levels. An assessment of code provisions for minimum shear reinforcememt, and the prediction and comparison of the ultimate shear capacity are also presented.

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.49 no.4
• /
• pp.335-342
• /
• 2021

By using HLS when developing a communication system FPGA, HDL code can be automatically generated from a little modified C/C++ source code used for performance verification, which has the advantage of shortening the development period. In this paper, a method of designing a telemetry standard 106-17 LDPC decoder in C language is proposed using Xilinx's Vivado HLS, and by synthesizing Spartan-7 and Kintex-7 as target devices, throughput and FPGA utilization rate was compared.