• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.25 no.11
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• pp.1197-1200
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• 2014

Two test standards to be applied for evaluating shielding effectiveness of HEMP protection facilities, MIL-STD-188-125-1 and IEEE std. 299, provide different test results in spite of the same facility. In particular, at the frequency range of 10 kHz~20 MHz, it is confirmed that the test results by the IEEE Std. 299 are about 20~30 dB lower than the evaluated results by MIL-STD-188-125-1. These results are due to the different measurement conditions specified in the two test standards. Therefore, IEEE Std. 299 can be applied for the shortening of test distance, but the required SE performance based on MIL-STD-188-125-1 must be modified.

• Journal of the Korean Society for Heat Treatment
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• v.30 no.1
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• pp.17-20
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• 2017

Mechanical properties of STD61 steel are compared with those of carburized STD61 steel when both are quenched and tempered in vacuum heat treatment. Mechanical properties of carburized STD61 steel are improved better than STD61 steel in hardness, tensile strength, impact energy and wear resistance.

• Journal of Aerospace System Engineering
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• v.11 no.6
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• pp.76-83
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• 2017

The MIL-STD-1553 standard has been used for over 40 years as a data bus technology for high-reliability mobile systems. However, 1 Mbps transmission speed is absolutely insufficient to implement sensor data convergence, which is an essential requirement of modern aerospace systems. In this paper, we analyze the hierarchical structure of the MIL-STD-1553B version specification and describe several methods to increase the transmission speed without losing the advantages of the existing MIL-STD-1553 bus. In addition, we analyzed the R & D cases of the high-speed MIL-STD-1553 technology, which have been conducted in leading aerospace countries.

• Journal of Korean Public Health Nursing
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• v.35 no.2
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• pp.239-253
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• 2021

Purpose: An STD (Sexually transmitted disease) prevention program was developed for the elderly, and its effect on their knowledge about STDs, STD prevention attitudes, social support, STD prevention self-efficacy, STD prevention behaviors, and STD presence were verified. Method: The subjects of the study were 50 people (25 in the experimental group and 25 in the control group). The experimental group was provided with a six-session STD prevention program. Result: In the experimental group, the knowledge about STD (t=105.00, p<.001), STD prevention attitudes (t=7.60, p<.001), and social support (F=87.11, p<.001), STD prevention self-efficacy (U=28.00, p<.001), and STD prevention behavior (t=7.38, p<.001) were improved significantly. Conclusion: The results highlight the need for nursing intervention for STD prevention to the elderly using the program developed for the prevention of STDs for the elderly.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.5 no.3
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• pp.204-209
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• 2004

Using STD11 and STS3 as a mold set, accuracy of a mold product could be improved by heat treatment. Results of Charpy impact test and measurement of retained austenite in STS3 and STD11, STD11 was superior than STS3 in effect of sub-zero treatment and stability of working and measure. Decrease of retain austenite by sub-zero treatment in STS3 did not occured.

• Journal of the Korean Society for Heat Treatment
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• v.14 no.1
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• pp.27-34
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• 2001

The effects of pre-heat treatment(Q/T) on microstructure and hardness of STD11 and STD61 tool steel nitrided by micro-pulse plasma were investigated. The quenching temperature for obtaining matrix hardness of STD11 and STD61 steel on range of HRC 50 to HRC 60 desired for machine parts is about $1070^{\circ}C$ and $1020^{\circ}C$ respectively. The hardness of STD11 and STD61 quenched at the temperature was HRC 63 and HRC 56 respectively. The nitrided case depth of STD11 and STD61 nitrided at $550^{\circ}C$ for 5 hours was independent of pre-heat treatment condition and the depth was approximately $100{\mu}m$. However, hardness and compactness of nitrided layer on Q/T treated specimen were higher than the annealed specimen. The case depth increased linearly with the increase of nitriding temperature, however, the hardness of nitrided layer decreased with the increase of temperature. Phase mixture of ${\gamma}-Fe_4N$ and ${\varepsilon}-Fe_{2-3}N$ was detected by XRD analysis in the nitrided layer formed at the optimum nitriding condition. The optimum nitriding temperature was approximately $490^{\circ}C$ which was $10^{\circ}C$ lower than the tempering temperature for preventing softening behavior of STD11 and STD61 matrix during nitriding process and the surface hardness of nitrided layer obtained by optimum pre-heat treatment condition was about Hv1400.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.21 no.3
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• pp.568-577
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• 2017

IEEE Std 1609.2 was defined for the support of communication security functions in the WAVE (Wireless Access in Vehicular Environments) system. IEEE Std 1609.2 defined the message structures of the security services and managements on the vehicular communication by using ASN.1 (Abstract Syntax Notation One). Also, this security message structures shall be encoded using the COER (Canonical Octet Encoding Rules). In this paper, we designed and implemented the IEEE Std 1609.2 message encoder/decoder handling the security messages defined in IEEE Std 1609.2. The designed encoder/decoder consists of three modules as follows : a module generating the message of C language data structures in accord with IEEE Std 1609.2 message structures, a message encoder module, a message decoder module. And the encoder/decoder was implemented on the Linux environment. Also we analyzed the performance by measuring the performance speed of the encoder/decoder implemented.

• Korean Journal of Adult Nursing
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• v.28 no.4
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• pp.482-490
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• 2016

Purpose: The purpose of the study was to examine the impact of self-efficacy in the prevention of sexually transmitted diseases (STD), knowledge of and susceptibility to STD, and the role of gender in sexual autonomy. Methods: Data were collected from 267 college students using self-report questionnaires during the period from the first to the twentieth of June 2015. Data were analyzed using $x^2$ test, Fisher's exact test, t-test, Pearson correlation coefficients, simple and multiple regression techniques with the PASW/WIN 20.0 program. Mediation analysis was performed according to the Baron and Kenny method and Sobel test. Results: In male students, self-efficacy for STD prevention showed a full mediating effect in the relationship between STD susceptibility and sexual autonomy (${\beta}$=-.08, p=.370). But in female students, it had a partial mediating effect (${\beta}$=-.25, p=.001). And self-efficacy for STD prevention showed partial mediating effects in the relationship between knowledge of STD and sexual autonomy in the both male (${\beta}$=.25, p=.005) and female students (${\beta}$=.33, p<.001). Conclusion: To enhance college students' sexual autonomy, it may be useful to build effective strategies enhancing students' knowledge about and susceptibility to STD and to develop a self-efficacy promotion program for college students.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.9
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• pp.60-67
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• 2013

Test cost reduction is necessary to test a complex System-on-a-Chip(SoC) which adopts various Intellectual Properties (IP). In this paper, test architecture with low pin count which is able to IP-based SoC test, using IEEE Std. 1149.7 and IEEE Std. 1500, is proposed. IEEE Std. 1500 provides independent access mechanism for each IP in IP-based SoC test. In this paper, just two test pins are required by composing that these independent access mechanism can be controlled by IEEE Std. 1149.7. The number of Chips which are tested at the same time is increased by reducing required test pin count at wafer and package level test, and consequently the overall manufacturing test cost will be reduced significantly.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.22 no.6
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• pp.50-60
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• 2008

The ANSI/IEEE Std. 80-2000 method has been commonly used to design grounding system for the South Korea domestic market. However, the appropriateness of this method to the ground design environment has not yet been examined. This paper presents a new design grounding system method that complements the ANSI/IEEE Std. 80-2000 method, when the new method is a lied to thickness, dangerous voltage, and grid spaced computations for grounding conductors. Furthermore, this paper examines reliability and economic efficiency issues by comparing of the ANSI/IEEE Std. 80-2000 Annex B's case study with the original method.