• Title/Summary/Keyword: MIL

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Analysis for Next-generation High-Speed MIL-STD-1553 Bus Technology (차세대 고속 MIL-STD-1553 버스 기술 분석)

  • Jung, Jin Pyong;Lee, Sang Gye;Lee, Seung Hoon
    • 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.

Ni Nanoparticles Supported on MIL-101 as a Potential Catalyst for Urea Oxidation in Direct Urea Fuel Cells

  • Tran, Ngan Thao Quynh;Gil, Hyo Sun;Das, Gautam;Kim, Bo Hyun;Yoon, Hyon Hee
    • Korean Chemical Engineering Research
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    • v.57 no.3
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    • pp.387-391
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    • 2019
  • A highly porous Ni@MIL-101catalyst for urea oxidation was synthesized by anchoring Ni into a Cr-based metal-organic framework, MIL-101, particles. The morphology, structure, and composition of as synthesized Ni@MIL-101 catalysts were characterized by X-Ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and transmission electron microscopy. The electro-catalytic activity of the Ni@MIL-101catalysts towards urea oxidation was investigated using cyclic voltammetry. It was found that the structure of Ni@MIL-101 retained that of the parent MIL-101, featuring a high BET surface area of $916m^2g^{-1}$, and thus excellent electro-catalytic activity for urea oxidation. A $urea/H_2O_2$ fuel cell with Ni@MIL-101 as anode material exhibited an excellent performance with maximum power density of $8.7mWcm^{-2}$ with an open circuit voltage of 0.7 V. Thus, this work shows that the highly porous three-dimensional Ni@MIL-101 catalysts can be used for urea oxidation and as an efficient anode material for urea fuel cells.

A Study on the Analysis of Educational Content and Curriculum of UNESCO's Media and Information Literacy (UNESCO의 미디어와 정보 리터러시의 교육내용 분석과 교육과정에 관한 연구)

  • Park, Juhyeon
    • Journal of the Korean Society for Library and Information Science
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    • v.54 no.2
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    • pp.349-374
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    • 2020
  • The purpose of this study is to explore the concept, contents, and curriculum of MIL(Media and Information Literacy) proposed by UNESCO from the perspective of Library and Information Science to obtain the basic information necessary for the revision of the Library and Information Life curriculum and to derive implications. As a result of the analysis, UNESCO used the term MIL to highlight the characteristics and importance of information literacy in media education. The information literacy and library literacy were key factors in forming the concept and curriculum of MIL. UNESCO also presented 'information literacy and library skills' as essential areas of the MIL curriculum, as well as core competencies and achievement criteria. In addition, the MIL curriculum actively embraces information literacy and library literacy, with the five laws of MIL based on the five laws of library science. The results of this study could be used as a basis for the reason why MIL should be actively accepted in Library and Information Science and for the revision of Library and Information Life curriculum.

An Analysis and Implications Exploration of Media and Information Literacy (MIL) Curriculum in the Philippines (필리핀의 미디어정보 리터러시 교육과정 분석과 시사점 탐색)

  • Park, Juhyeon
    • Journal of Korean Library and Information Science Society
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    • v.52 no.2
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    • pp.331-355
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    • 2021
  • The purpose of this study is to derive the implications of operating the Media and Information Literacy (MIL) curriculum in Korea through analysis of MIL curriculum and guidance in the Philippines. The Philippine Ministry of Education runs the MIL as a core subject that high school students in grades 2-3 had to complete. MIL in the Philippines is a tool curriculum that integrates information, media, and digital literacy. In the MIL curriculum, a total of 17 units are designed to be operated for a total of 80 hours, 20 weeks in a semester. And it presents two content criteria, two achievement criteria and 58 learning competencies. The implications drawn from the research results are as follows. First, the chapter presented in the MIL curriculum can be composed only of the knowledge of a higher category or core concept of subject content. Second, it is necessary to present the concept of the term used in the MIL curriculum and specific examples according to the concept. Third, it is necessary to specify the contents necessary for practice in the MIL textbook and to strengthen the competence for the function. MIL, proposed by UNESCO and designated and operated as a subject in the Philippines, needs to be designated as a subject in Korea and operated as a curriculum.

Synthesis of CdxZn1-xS@MIL-101(Cr) Composite Catalysts for the Photodegradation of Methylene Blue

  • Yang, Shipeng;Peng, Siwei;Zhang, Chunhui;He, Xuwen;Cai, Yaqi
    • Nano
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    • v.13 no.10
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    • pp.1850118.1-1850118.17
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    • 2018
  • Nanoparticles of the semiconductor catalyst $Cd_xZn_{1-x}S$ were embedded into the metal organic framework MIL-101(Cr) to obtain $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites. These materials not only possess high surface areas and mesopores but also show good utilization of light energy. The ultraviolet-visible diffuse reflectance patterns of $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites showed that $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) possessed good visible light response ability among the synthesized nanocomposites. The photocatalytic performance of the $Cd_xZn_{1-x}S@MIL-101$(Cr) nanocomposites were tested via degradation and mineralization of methylene blue in neutral water solution under light irradiation using a 300W xenon lamp. As a result, using $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) as a catalyst, 99.2% of methylene blue was mineralized within 30 min. Due to the synergistic effect of adsorption by the MIL-101(Cr) component and photocatalytic degradation provided by the $Cd_{0.8}Zn_{0.2}S$ component, the $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) catalyst displayed superior photocatalytic performance relative to $Cd_{0.8}Zn_{0.2}S$ and MIL-101(Cr). Furthermore, $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) possessed excellent stability during photodegradation and exhibited good reusability. The remarkable photocatalytic performance of $Cd_{0.8}Zn_{0.2}S@MIL-101$(Cr) is likely due to the effective transfer of electrons and holes at the heterojunction interfaces.

Effects of Perceived Death and Self-esteem on Meaning in Life among University Students (대학생의 죽음에 대한 인지도와 자아존중감이 삶의 의미에 미치는 영향)

  • Kim, Chun-Gill
    • Journal of Korean Public Health Nursing
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    • v.27 no.3
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    • pp.539-550
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    • 2013
  • Purpose: The objectives of this study were to investigate the level of meaning in life(MIL) among university students as well as identify the effects of death perception, including good death and concerns about dying, and self-esteem on MIL. Methods: A questionnaire survey was developed and carried out using a convenient sampling method (N=301). Data were analyzed by applying descriptive statistics, t-test, ANOVA, Duncan test, Pearson's correlation coefficient, and stepwise multiple regression. Results: The average score for MIL was 4.70 on a 7-point scale. The factor of purpose of life received highest score among all factors in MIL. MIL was positively correlated with age, good death, and self-esteem. However, concerns about dying were negatively correlated with MIL. MIL showed a strong association with self-esteem(r=.72). Specifically, self-esteem(${\beta}$=.608), satisfaction of school life(${\beta}$=.190), relationship with parents(${\beta}$=.180), good death(${\beta}$=.080), school grades(${\beta}$=.078), and age(${\beta}$=.074) all significantly influenced MIL. These variables accounted for 61.0% of the total variance. Conclusion: The results show that self-esteem is an important factor for MIL among university students. Therefore, self-esteem should be carefully considered to increase their MIL. These research findings can be utilized to support programs such as counseling and education of university students.

Comparisons on Specifications of Mating Electrical Connectors for NASA Standard Initiators (나사 표준 착화기 (NASA Standard Initiators) 연결 전기 커넥터의 규격 비교)

  • Kim, In Sung;Jeong, Eun Hwan
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2017.05a
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    • pp.418-422
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    • 2017
  • Based on published materials, we compared specifications of mating electrical connectors for the NASA Standard Initiators NSI-1,2,3 with each other after the initiator specifications summary. The mating connector specifications for NSI-1,2 are MSFC-40M38298 and MIL-DTL-26482, series1 while for NSI-3 is MIL-DTL-38999, series3. The MIL-DTL-38999, series3 has the highest overall environmental resistance performance. MSFC-40M38298 is the next and MIL-DTL-26482, series1 follows. In particular, if initiators be used under severe shock and vibration environments, the MIL-DTL-38999, series3 should be applied.

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A Study on the Adsorption Properties of Diisopropyl Methyl Phosphonate on Chromium-Based Metal-Organic Frameworks Using Acetic Acid as a Modulator (아세트산을 조절인자로 제작한 크롬 기반 금속유기골격체의 diisopropyl methyl phosphonate 흡착 특성 연구)

  • Sangjo Jeong
    • Applied Chemistry for Engineering
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    • v.34 no.6
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    • pp.596-602
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    • 2023
  • Chromium-based metal-organic frameworks (MIL-101(Cr)) were synthesized, and their potential use as a filling material for gas masks or protective clothing was assessed through adsorption experiments using diisopropyl methyl phosphate (DIMP) as a simulant for chemical warfare agents. MIL-101(Cr) was prepared using acetic acid (MIL-101(Cr)-A) and sodium hydroxide (MIL-101(Cr)-N) as modulators. The use of acetic acid as a modulator resulted in a larger specific surface area and a higher DIMP adsorption capacity. MIL-101(Cr)-A absorbed approximately 160% of its own weight of moisture when exposed to an environment with a relative humidity of 90% for 10 days, surpassing other adsorbents such as activated carbon. The DIMP adsorption capacity of MIL-101(Cr)-A decreased to about 40% of its initial adsorption capacity after 24 hours of exposure to an environment with a relative humidity of 90%. However, this capacity is still higher compared to that of activated carbon used in commercial gas masks, suggesting a high potential for future use as a filling material for gas masks or protective clothing.

Software Development Process of Military Aircraft based on MIL-HDBK-516C (MIL-HDBK-516C 기반의 군용항공기 탑재 소프트웨어 개발 프로세스)

  • Heo, Jin-Gu;Moon, Yong-Ho
    • Journal of Aerospace System Engineering
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    • v.15 no.3
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    • pp.71-78
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    • 2021
  • Since most functions of modern aircraft are controlled by software, software errors are directly related to aircraft safety. The criterion in Chapter 15 of the MIL-HDBK-516C addresses safe development and verification of military aircraft software. As the U.S. Air Force repeatedly experienced non-compliance with Chapter 15 criterion of the MIL-HDBK-516C, it published an Airworthiness Circular (AC-17-01) as a guide to meeting the criterion. In this paper, Chapter 15 of MIL-HDBK-516C, AC-17-01 and the SW Qualification Guideline (DO-178C) as applied by the Federal Aviation Administration are compared and analyzed. For the analysis, a matching ratio formula between the MIL-HDBK-516C criteria specified in AC-17-01 and the DO-178C specified in MIL-HDBK-516C criteria is defined. The sections that satisfy MIL-HDBK-516C criterion are derived when AC-17-01 or DO-178C matches. Based on the analysis results, the aircraft software development process is established and examples of application of Chapter 15 of MIL-HDBK-516C are addressed.

VCO Oscillation Characteristics by Varying the Length of the MSL of LC Resonator (LC공진기의 MSL길이에 따른 VCO 발진 특성)

  • 이동희;정진휘
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.15 no.5
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    • pp.412-418
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    • 2002
  • In this paper, the authors present the simulation results and the experimental considerations on the effects of the effects of the VCO oscillation characteristics caused by varying the length of the MSL and the composition capacitance of LC resonation circuity. Simulation was accomplished by nonlinear RF circuit simulator for designing and analyzing the RF characteristis of VCO. The samples with 3 different MSL lengths of which the length is 140mil, 280mil and 560mil respectively were fabricated by screen printing process. The oscillation frequency of each sample(VCO) was tuned to UHF band (750MHz~900MHz) by varying the capacitance of LC resonator circuit. The experimental results showed that the values of phase noise were -82, -93, -97[dBc/Hz] at 50[kHz] offset frequency, the pushing figures were 114, 94, 318[kHz] at applied voltage of $3\pm0.15$[V] and the harmonics were -21, -16, -13[dBc] for MSL lengths of 140mil 280mil, 560mil respectively. The frequency and output variation width were 779~898[MHz], -36~-33[dBm] for MSL with 140mil length; 818~836[MHz], -27.19~27.06[dBm] for 280mil; 751.54~751.198[MHz], -33.44~-33.31[dBm] for 560mil.