• Title/Summary/Keyword: application-specific function

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Thermal Properties of 0.9CaMgSi2O6-0.1MgSiO3 Glass-Ceramics

  • Jeon, Chang-Jun;Sun, Gui-Nam;Lee, Jong-Kyu;Ju, Han-Sae;Kim, Eung-Soo
    • Journal of the Korean Ceramic Society
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    • v.49 no.1
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    • pp.111-117
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    • 2012
  • Dependencies of thermal properties on the crystallization behavior of $0.9CaMgSi_2O_6-0.1MgSiO_3$ glass-ceramics were investigated as a function of heat-treatment temperature from $750^{\circ}C$ to $950^{\circ}C$. The crystallization behavior of the specimens depended on the heat-treatment temperature, which could be evaluated by differential thermal analysis (DTA), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction (XRD) analysis by the Rietveld-reference intensity ratio (RIR) combined procedure. With an increase of the heat-treatment temperature, the thermal conductivity and thermal diffusivity of the heat-treated specimens increased. These results could be attributed to the increase of crystallization with heat-treatment temperature. However, the specific heat capacity of the heat-treated specimens was not affected by the heat-treatment temperature. The thermal conductivities measured from $25^{\circ}C$ to $100^{\circ}C$ were also discussed for application to lighting-emitting diode (LED) packages and substrate materials.

A Study on the Space Design of the Virtual Reality Simulation Exclusive Space (가상현실(VR) 시뮬레이션 전용관 공간설계에 관한 연구)

  • 임종엽;유태관
    • Korean Institute of Interior Design Journal
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    • no.33
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    • pp.115-121
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    • 2002
  • This study is based on the Virtual Reality Space what grow rapidly compared with other space type. We make a certain definite possibilities by the functional, material, scientific and conceptual space comparison approved with existing visual space about the function of sound and visual system & the application of the mechanical system. Symbol and Expression Media are showing characteristics more than a tool in Modern times being changed from materialistic world to immaterial one. Especially, Augmented Reality, which is the new technology showing human beings real world and virtual world simultaneously recently and being exceeded to existent many limits, is going ahead. Simulation space is the technology one which can be applied to various fields such as culture, industry and education etc., and it helps human beings to overcome their limitations. The gains from this study are the specified and detailed yardsticks and cases of Simulation(space) facilities classified as a specific space. Therefore, the space mainly consists of the parts on size, equipment, and material etc. judging from technical point of view. Architectural Space, especially, should be considered very importantly in the middle of the transition from image realization to experience. The comprehension on various contents together with mechanical facilities will be requested to the connection applied to physical space expression, and that is what we have to study continuously afterward.

Glial Mechanisms of Neuropathic Pain and Emerging Interventions

  • Jo, Daehyun;Chapman, C. Richard;Light, Alan R.
    • The Korean Journal of Pain
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    • v.22 no.1
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    • pp.1-15
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    • 2009
  • Neuropathic pain is often refractory to intervention because of the complex etiology and an incomplete understanding of the mechanisms behind this type of pain. Glial cells, specifically microglia and astrocytes, are powerful modulators of pain and new targets of drug development for neuropathic pain. Glial activation could be the driving force behind chronic pain, maintaining the noxious signal transmission even after the original injury has healed. Glia express chemokine, purinergic, toll-like, glutaminergic and other receptors that enable them to respond to neural signals, and they can modulate neuronal synaptic function and neuronal excitability. Nerve injury upregulates multiple receptors in spinal microglia and astrocytes. Microglia influence neuronal communication by producing inflammatory products at the synapse, as do astrocytes because they completely encapsulate synapses and are in close contact with neuronal somas through gap junctions. Glia are the main source of inflammatory mediators in the central nervous system. New therapeutic strategies for neuropathic pain are emerging such as targeting the glial cells, novel pharmacologic approaches and gene therapy. Drugs targeting microglia and astrocytes, cytokine production, and neural structures including dorsal root ganglion are now under study, as is gene therapy. Isoform-specific inhibition will minimize the side effects produced by blocking all glia with a general inhibitor. Enhancing the anti-inflammatory cytokines could prove more beneficial than administering proinflammatory cytokine antagonists that block glial activation systemically. Research on therapeutic gene transfer to the central nervous system is underway, although obstacles prevent immediate clinical application.

Development of STEAM Instructional Materials using Arduino for Creative Engineering Design Class in High Schools and Its Application (일반계고의 창의공학설계 수업을 위한 아두이노 기반 STEAM 수업자료 개발과 적용)

  • Lee, Dae-Seok;Lim, Yeong-Dae;Kim, Jinsoo
    • Journal of Engineering Education Research
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    • v.23 no.1
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    • pp.3-9
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    • 2020
  • The purpose of the study was to develop the Arduino based STEAM instruction materials for creative engineering design class. PDIE model was used in this study. We developed a STEAM lesson plan and a STEAM lesson worksheet for a total of six sessions through the steps of preparation, development, implementation and evaluation. The validity of the instruction materials was evaluated by the 10 experts using a survey. The instruction materials were applied to the class (52 students attended) of the creative engineering designs unit in technology and home economics subject. The class satisfaction and the creative solving-problem ability were examined after the calss. The class satafacition was high as the average of 10 item was 4.57 (out of 5). The paired t-test was conducted to compare the means of the creative solving-problem ability. It was observed that 'understanding and mastery of knowledge, thought, function and skills in a specific domain', 'divergent thinking', 'critical and logical thinking' and ' motivational factors' were significantly increased after the class. The instruction materials develped in this study were successfully designed to enhance the creative solving-problem ability by designing creative tasks and to intrique the interest by adding visual and auditory stimuli with the Arduino.

An Experimental Study on the design of the thermister thermometer (전기온도계 제작에 관한 실험적 연구)

  • Yun, Dork-Ro;Kim, Ik-Su
    • Journal of Preventive Medicine and Public Health
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    • v.6 no.1
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    • pp.65-70
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    • 1973
  • The study in the fild of medical instrument has been out of the interest by any of the life scientist in Korea. Especially, the recent developments in the medical electromics are remarkable one. Authors planned this study to ascertain the possibility of setting up the thermister thermometer with available accessories of demestic prouducts including some specific foreign assembly parts. By proper use of the thermister as one of the wheatstone bridge, we could detect tile resistance variations due to the environmental temperature variace. The intensive care for the bridge circuit and compensation scheme was required. The calibration procedure adopted here makes it possible to read the current as the temperature. The temperature range was determined by the examination and construction of the graph of the resistance-temperature variation. The determination of electric current, available ambient-temperature, the reduction of excessive current and self-heating of the thermister were made. Renovation in response-velocity was under taken too. This electronic thermometer was designed and assembled by the circuitry developed in accordance with the maximum availability of domestic products with some foreign-made parts. The result of our experiment showed very stable function and proved to be the most promissing item in the actual application as long as the thermistor thermister is concerned.

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Unambiguous Fiber Fabry-Perot Temperature Sensor by an Additional Partial Mirror (보조 반사체를 이용한 광섬유 페브리페로 간섭계형 온도센서의 성능향상)

  • Kim, Gwang-Su;Lee, Hong-Sik
    • The Transactions of the Korean Institute of Electrical Engineers C
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    • v.49 no.7
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    • pp.418-423
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    • 2000
  • The fiber Fabry-Perot interferometric(FFPI) sensor is well known in the field of industrial diagnosis due to its outstanding properties such as tiny size, simple and rugged structure, and easy interrogation. As other fiber interferometric sensors, it also suffers from ambiguous output caused by highly periodic feature in its optical transfer function. In most cases, the ambiguity leads to relatively short dynamic operating range and long processing time during power-on reset, which limits its application to some specific fields requiring very high resolution. In this paper a method based on double sensing scheme was proposed to overcome the above difficulty. By employing a fringe selection auxiliary FFPI sensor the original FFPI sensor can identify its true position on the phase domain. The performance test with 10mm FFPI sensor and a thermocouple temperature sensor for reference shows wide dynamic range 0-900$\ell$ keeping a reasonable resolution of 0.1$\ell$ over the entire range.

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A study on the measurement of thermophysical properties of ceramic dielectric materials by unsteady square wave pulse heating method (非定常方形波 펄즈 加熱에 의한 세라믹 誘電體의 熱物性値 測定에 관한 硏究)

  • 차경옥
    • Transactions of the Korean Society of Mechanical Engineers
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    • v.12 no.1
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    • pp.152-162
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    • 1988
  • In recent years, attention has been paid to the ceramic material next to metals and plastics due to its inherent characteristics, i.e., good hardness, resistance to heat and corrosion. Recently, various kinds of ceramic dielectrics have been developed for application in industry. It is of prime importance to know the thermophysical properties for wider use of these new materials. However, no extensive effort has been made for systematic measurement of the properties. In this paper, the dielectric constant of five different kinds of ceramic dielectrics ware measured. We call these samples as MgO.SiO$_{2}$, MgTiO$_{3}$, TiO$_{2}$, CaTiO$_{3}$, and BaTiO$_{3}$. Which are currently in commercial sue. The values of thermal dirrusivities, specific heats, and thermal conductivities of these ceramic dielectrics sere measured as a function of temperature ranging from room temperature to about 1300k.

Structural and Functional Measurements of a Space Truss Frame for Maintenance Works in Tunnels (터널의 유지보수공사 개선을 위한 가설 스페이스 트러스 프레임의 사용성 및 안정성 평가)

  • Lee, Dong Kyu;Kim, Do Hwan;Kim, Jin Ho
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.16 no.3
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    • pp.92-98
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    • 2012
  • This study shows details of a specific space truss frame structure devised to carry out maintenance and repair temporary works in tunnels. The purpose of this study is to verify structural safety and function of the innovative truss structure through an analysis tool, i.e.. ABAQUS, which is a suite of software application for finite element analysis and computer aided engineering. And then optimized size, i.e., thickness and diameter of truss members is evaluated in practice. In this study, construction methods in the temporary works are additionally represented by using the new space truss frame structure.

A review on the medicinal potentials of ginseng and ginsenosides on cardiovascular diseases

  • Lee, Chang Ho;Kim, Jong-Hoon
    • Journal of Ginseng Research
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    • v.38 no.3
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    • pp.161-166
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    • 2014
  • Ginseng is widely used for its promising healing and restorative properties as well as for its possible tonic effect in traditional medicine. Nowadays, many studies focus on purified individual ginsenoside, an important constituent in ginseng, and study its specific mechanism of action instead of whole-plant extracts on cardiovascular diseases (CVDs). Of the various ginsenosides, purified ginsenosides such as Rb1, Rg1, Rg3, Rh1, Re, and Rd are the most frequently studied. Although there are many reports on the molecular mechanisms and medical applications of ginsenosides in the treatment of CVDs, many concerns exist in their application. This review discusses current works on the countless pharmacological functions and the potential benefits of ginseng in the area of CVDs. Results: Both in vitro and in vivo results indicate that ginseng has potentially positive effects on heart disease through its various properties including antioxidation, reduced platelet adhesion, vasomotor regulation, improving lipid profiles, and influencing various ion channels. To date, approximately 40 ginsenosides have been identified, and each has a different mechanism of action owing to the differences in chemical structure. This review aims to present comprehensive information on the traditional uses, phytochemistry, and pharmacology of ginseng, especially in the control of hypertension and cardiovascular function. In addition, the review also provides an insight into the opportunities for future research and development on the biological activities of ginseng.

Design and experiment of the protocol using ASM2.0 : focusing on marine officers' mandatory reporting items (차세대 해상디지털통신기술 ASM2.0을 이용한 프로토콜 설계 및 실험 : 항해사의 의무보고 사항을 중심으로)

  • Kim, Kilyong;Kim, Do-yeon;Lee, Seojeong
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2015.10a
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    • pp.43-44
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    • 2015
  • AIS-ASM is a one of the study to provide a variety of maritime safety information as well as ship's position and navigational information that is their own function since 2004. This study aims to reduce the marine officer's workload through automating marine officer's mandatory reporting items using the one of the next maritime digital communication technology (ASM2.0). For this purpose, we designed and experimented of the ASM2.0 protocol through analyzing a domestic regulation about passenger flight and AIS-ASM message.

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