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Design and manufacture of mini loop coil probe style magnetic curer for peripheral nervous system treatment (말초신경계 치료를 위한 초미니 Loop-코일프로브 삽입형 자기치료기의 설계 및 제작)

  • Kim, Whi-Young;Choi, Jin-Young;Park, Sung-Jun;Kim, Hee-Je
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.2 no.1
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    • pp.153-169
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    • 2007
  • It is as result that study to apply mini magnet nerve curer in peripheral nervous system disease treatment. Design and embodied action power and Control Unit in cylinder form of magnet roof object firstly. Yielded service area about special quality of probe of roof object cylinder style and treatment area dimension and distance of treatment pulse secondly. Embody pulse forming course energy value by Probe's form by third, could embody treatment pulse by disease. Specially, through a special quality experiment, saved Damping pulse form and treatment pulse form etc. variously. Lately, embodied this to aid a little in disease treatment that follow that there is no invasion that there is no stimulation by medicine development. Go amplitude treatment pulse (traditional magneto-therapy of greatly great that strong) does curative effect greatest at short time and becomes thought that demand is magnified greatly at the future in this research.

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Research Trend of Soft Magnetic Composite Materials with High Energy Efficiency (고에너지효율 연자성 복합 분말 소재의 연구개발 동향)

  • Kim, Hwi-Jun
    • Journal of the Korean Magnetics Society
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    • v.21 no.2
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    • pp.77-82
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    • 2011
  • The use of soft magnetic materials have been increasing in the various industrial fields according to the increasing demand for high performance, automatic, miniaturing equipments in the recent our life. In this study, we investigated the effect of factors on the core loss and magnetic properties of electrical steel and soft magnetic composites. Furthermore, we reviewed the major efforts to reduce the core loss and improve the soft magnetic properties in the two main soft magnetic materials. Domain purification which results from reduced density of defects in cleaner electrical steels is combined with large grains to reduce hysteresis loss. The reduced thickness and the high electrical conductivity reduce the eddy current component of loss. Furthermore, the coating applied to the surface of electrical steel and texture control lead to improve high permeability and low core loss. There is an increasing interest in soft magnetic composite materials because of the demand for miniaturization of cores for power electronic applications. The SMC materials have a broad range of potential applications due to the possibility of true 3-D electromagnetic design and higher frequency operation. Grain size, sintering temperature, and the degree of porosity need to be carefully controlled in order to optimize structure-sensitive properties such as maximum permeability and low coercive force. The insulating coating on the powder particles in SMCs eliminates particle-to-particle eddy current paths hence minimizing eddy current losses, but it reduces the permeability and to a small extent the saturation magnetization. The combination of new chemical composition with optimum powder manufacturing processes will be able to result in improving the magnetic properties in soft magnetic composite materials, too.

The Medium Access Scheduling Scheme for Efficient Data Transmission in Wireless Body Area Network (WBAN 환경에서 효율적 데이터 전송을 위한 매체 접근 스케줄링 기법)

  • Jang, EunMee;Park, TaeShin;Kim, JinHyuk;Choi, SangBan
    • Journal of the Institute of Electronics and Information Engineers
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    • v.54 no.2
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    • pp.16-27
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    • 2017
  • IEEE 802.15.6 standard, a Wireless Body Area Network, aims to transfer not only medical data but also non-medical data, such as physical activity, streaming, multimedia game, living information, and entertainment. Services which transfer those data have very various data rates, intervals and frequencies of continuous access to a medium. Therefore, an efficient anti-collision operations and medium assigning operation have to be carried out when multiple nodes with different data rates are accessing shared medium. IEEE 802.15.6 standard for CSMA/CA medium access control method distributes access to the shared medium, transmits a control packet to avoid collision and checks status of the channel. This method is energy inefficient and causes overhead. These disadvantages conflict with the low power, low cost calculation requirement of wireless body area network, shall minimize such overhead for efficient wireless body area network operations. Therefore, in this paper, we propose a medium access scheduling scheme, which adjusts the time interval for accessing to the shared transmission medium according to the amount of data for generating respective sensor node, and a priority control algorithm, which temporarily adjusts the priority of the sensor node that causes transmission concession due to the data priority until next successful transmission to ensure fairness.

The Analysis of the Breakdown Voltage according to the Change of JTE Structures and Design Parameters of 4H-SiC Devices (4H-SiC 소자의 JTE 구조 및 설계 조건 변화에 따른 항복전압 분석)

  • Koo, Yoon-Mo;Cho, Doo-Hyung;Kim, Kwang-Soo
    • Journal of IKEEE
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    • v.19 no.4
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    • pp.491-499
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    • 2015
  • Silicon Carbide(SiC) has large advantage in high temperature and high voltage applications because of its high thermal conductivity and large band gap energy. When using SiC to design power semiconductor devices, edge termination techniques have to be adjusted for its maximum breakdown voltage characteristics. Many edge termination techniques have been proposed, and the most appropriate technique for SiC device is Junction Termination Extension(JTE). In this paper, the change of breakdown voltage efficiency ratio according to the change of doping concentration and passivation oxide charge of each JTE techniques is demonstrated. As a result, the maximum breakdown voltage ratio of Single Zone JTE(SZ-JTE), Double Zone JTE(DZ-JTE), Multiple Floating Zone JTE(MFZ-JTE), and Space Modulated JTE(SM-JTE) is 98.24%, 99.02%, 98.98%, 99.22% each. MFZ-JTE has the smallest and SZ-JTE has the largest sensitivity of breakdown voltage ratios according to the change of JTE doping concentration. Additionally the degradation of breakdown voltage due to the passivation oxide charge is analyzed, and the sensitivity is largest in SZ-JTE and smallest in MFZ-JTE, too. In this paper, DZ-JTE and SM-JTE is the best efficiency JTE techniques than MFZ-JTE which needs large doping concentration in short JTE width.

A Study on Changam, Lee Samman's a course of learning calligraphy and calligraphy theory (창암(蒼巖) 이삼만(李三晩)의 학서(學書) 연마와 서예론(書藝論) 고찰)

  • Kim, Doyoung
    • The Journal of the Convergence on Culture Technology
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    • v.6 no.1
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    • pp.327-334
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    • 2020
  • Changam, Lee Samman(1770~1845), who created his own handwriiting to be referred to as the three great writers of the late Joseon Dynasty, the valued 'beobgo'. Based on the calligraphy of the Han-Wi era, Lee Kwangsa who completed DonggugJinche was regarded as the teacher of the heart. In his later years, he wrote 『ChangamSeogyeol』 to teach how to use the right brush, revealing the basic principles of universal calligraphy and his own calligraphy. The typeface of Changam is completed by choseo through the establishment of haeseo geungol. For this, I valued Han-Wi's haeseo training, OnhuGanwon Han-Wi geungol shows a state without natural law. This shows that nature is the core and ultimate goal of Changam calligraphy theory. This is a return to the state of 'No law' at the height of the law, where eum-yang is created and bizarreness occurs when form, power and energy are promoted. On the other hand, he emphasized that jangbeob and pochi form IlunMujeog DeugpilCheonyeon when expressing naturalness as it is, without being bound by the old law. His typeface constantly tried to combine the beauty of Joseon's own calligraphy while sublimating nature into art. Thus, he acquired IlunMujeog, a body rich in geungol and full of vitality and dynamism. And DeugpilCheonyeon achieved aesthetics with the highest level of excellence, embodied as the original 'Haengunyusu Typeface', and further developed handwriiting and Calligraphy spirit of DonggugJinche in Honam province.

Characteristics of Strong Alkaline Electrolyzed Water Produced in All-in-one Electrolytic Cell (일체형 전해조에서 생산된 강알카리성 전해수의 특성)

  • Lee, Ho Il;Rhee, Young Woo;Kang, Kyung Seok
    • Clean Technology
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    • v.18 no.4
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    • pp.446-450
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    • 2012
  • Strong alkaline electrolyzed water which is produced in cathode by electrolyzing the solution where electrolytes (NaCl, $K_2CO_3$ etc.) are added in diaphragm electrolytic cell, is eco-friendly and has cleaning effects. So, it is viewed as a substitution of chemical cleaner. In addition, strong alkaline electrolyzed water is being used by some Japanese automobile and precision parts manufacturing industries. When strong alkaline electrolyzed water is produced by using diaphragm electrolytic cell, it is necessarily produced at the anode side. Since strong acidic electrolyzed water produced is discarded when its utilization cannot be found, production efficiency of electrolyzed water is consequently decreased. Also, there is a weakness electrolytic efficiency is decreasing due to the pollution of diaphragm. In order to overcome this, non-diaphragm all-in-one electrolytic cell integrated with electrode reaction chamber and dilution chamber was applied. Strong alkaline electrolyzed water was produced for different composition of electrolytes, and their properties and characteristics were identified. In comparing the properties between strong alkaline electrolyzed water produced in diaphragm electrolytic cell and that produced in all-in-one electrolytic cell, the differences in ORP and chlorine concentration were found. In emulsification test to confirm surface-active capability, similar results were obtained and strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell was identified to be useable as a cleaner like strong alkaline electrolyzed water produced in diaphragm electrolytic cell. Strong alkaline electrolyzed water produced in non-diaphragm all-in-one electrolytic cell is thought to have sterilizing power because it has active chlorine which is different from strong alkaline electrolyzed water produced in diaphragm electrolytic cell.

Selection of Integrated Concepts Across Science and Humanities Using the Delphi Method (과학과 인문학의 통합개념 선정을 위한 델파이 연구)

  • Kim, Jiyoung;Park, Jieun;Yoon, Heojeong;Park, Eunmi;Bang, Dami
    • Journal of The Korean Association For Science Education
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    • v.34 no.6
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    • pp.549-558
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    • 2014
  • Integrated concepts that are broad enough to embrace facts, principles, laws, and concepts of multiple disciplines could become the core of integrated education. Integrated concept-centered education enables effective and practical learning. In this study, the Delphi Method was implemented targeting experts in science (physics, life science, chemistry, and earth science) and humanities (history, geology, economics, ethics, and politics) to find out the integrated concept that can be used to design the concept-centered integrated education in the Republic of Korea. 124 experts participated in this survey. Delphi survey was conducted for three rounds. In the first round, an open questionnaire was given to experts to collect feasible integrated concepts in each major field. Then, in the second round experts were asked to select integrated concepts that could be used practically in the field of their major. In the third round, the integrated concept with selection frequency over medium value were given. They were asked to evaluate the applicability of integrated concepts by using the Likert-scale questionnaire. Through this process, content validity was analyzed. As a result, five integrated concepts (change, interaction, space-time, energy, and equilibrium) were selected for the inter-science integration. And thirteen integrated concepts (conflict, community, relationship, structure, power, diversity, culture, change, society, interaction, freedom, justice, and equality) were chosen for the inter-humanities integration. Finally, for the science-humanities integration, seven integrated concepts (structure, diversity, change, interaction, cycle, system, and environment) were determined.

The Effects of Coupling Agent and Crosslinking Agent in the Synthesis of Acrylic Pressure Sensitive Adhesive for Polarizer Film (편광필름용 아크릴 점착제의 합성에서 커플링제와 가교제의 효과)

  • Lim, Chang-Hyuk;Ryu, Hoon;Cho, Ur-Ryong
    • Polymer(Korea)
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    • v.33 no.4
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    • pp.319-325
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    • 2009
  • The solution polymerization was conducted to synthesize pressure sensitive adhesive for polarizer film using acrylic monomers. 2-Ethylhexylacrylate, butylacrylate, acrylic acid were used as acrylic monomers. The ratio was 2-ethylliexylacrylate:butylacrylate:acrylic acid=25:50:3.6 by reflecting $-40^{\circ}C$ of glass transition temperature in the pressure sensitive adhesive. When 1 wt% of coupling agent was added to the polymerized pressure sensitive adhesive, the light transmissivity was significantly increased. This result is due to the enhancement of adhesive power against liquid crystal cell by Si-O bond of coupling agents. Cross-linking agent was added by 0.5, 1.0, and 1.5 wt% with respect to the synthesized polymer. Initial tackiness decreased, while cohesion increased with increasing crosslinking agent. In the analysis of contact angle, the increase of crosslinking agents yielded the enhancement of surface energy, resulting in the decrease of contact angle. From the measurement of heat resistance, the acrylic pressure sensitive adhesive showed excellent heat resistance regardless of change in temperature and contents in crosslinking agent. In the observation of a cutting plane, the increased crosslinking agent represented a smoother and cleaner section. Comprehensively, the optimum additive amount of crosslinking agent was determined to be 1.0 wt% to monomer.

INNOVATIVE CONCEPT FOR AN ULTRA-SMALL NUCLEAR THERMAL ROCKET UTILIZING A NEW MODERATED REACTOR

  • NAM, SEUNG HYUN;VENNERI, PAOLO;KIM, YONGHEE;LEE, JEONG IK;CHANG, SOON HEUNG;JEONG, YONG HOON
    • Nuclear Engineering and Technology
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    • v.47 no.6
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    • pp.678-699
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    • 2015
  • Although the harsh space environment imposes many severe challenges to space pioneers, space exploration is a realistic and profitable goal for long-term humanity survival. One of the viable and promising options to overcome the harsh environment of space is nuclear propulsion. Particularly, the Nuclear Thermal Rocket (NTR) is a leading candidate for nearterm human missions to Mars and beyond due to its relatively high thrust and efficiency. Traditional NTR designs use typically high power reactors with fast or epithermal neutron spectrums to simplify core design and to maximize thrust. In parallel there are a series of new NTR designs with lower thrust and higher efficiency, designed to enhance mission versatility and safety through the use of redundant engines (when used in a clustered engine arrangement) for future commercialization. This paper proposes a new NTR design of the second design philosophy, Korea Advanced NUclear Thermal Engine Rocket (KANUTER), for future space applications. The KANUTER consists of an Extremely High Temperature Gas cooled Reactor (EHTGR) utilizing hydrogen propellant, a propulsion system, and an optional electricity generation system to provide propulsion as well as electricity generation. The innovatively small engine has the characteristics of high efficiency, being compact and lightweight, and bimodal capability. The notable characteristics result from the moderated EHTGR design, uniquely utilizing the integrated fuel element with an ultra heat-resistant carbide fuel, an efficient metal hydride moderator, protectively cooling channels and an individual pressure tube in an all-in-one package. The EHTGR can be bimodally operated in a propulsion mode of $100MW_{th}$ and an electricity generation mode of $100MW_{th}$, equipped with a dynamic energy conversion system. To investigate the design features of the new reactor and to estimate referential engine performance, a preliminary design study in terms of neutronics and thermohydraulics was carried out. The result indicates that the innovative design has great potential for high propellant efficiency and thrust-to-weight of engine ratio, compared with the existing NTR designs. However, the build-up of fission products in fuel has a significant impact on the bimodal operation of the moderated reactor such as xenon-induced dead time. This issue can be overcome by building in excess reactivity and control margin for the reactor design.

Introduction process of 'Corn' and its interrelation with 'Chinese millet' and 'Indian millet' (옥수수(옥촉서(玉蜀黍))의 도입과정과 기장(태(泰)), 수수(촉서(蜀黍))와의 상관관계)

  • Kim, Jong-dug;Koh, Byung-hee;Song, Il-byung
    • Journal of Sasang Constitutional Medicine
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    • v.10 no.2
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    • pp.163-180
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    • 1998
  • In 1492 year, the corn originated in America continent had spread all over the world after spreading into Europe by Columbus. Since the Corn had a similar shape with adlai's one (Yulmoo(율무)), it had been written by the different name of adlai (Yulmoo) at the "訓蒙字會(Hun-mong-ja-hoe)(1527)". Therefore we should consider "Hun-mong-ja-hoe" is the first record of the corn and it is a significant historic record in the civilization exchange between the Orient and the Occident that this record has the only difference of around 30 years later after the spreading corn to Europe. However, this is on the assumption that it is correct for a scholar of Korean literature to persist in that '叡山本' of "Hun-mong-ja-hoe" could be considered as the first edition. The corn had been once classified as a same kind of the Chinese millet because the people had been recognized the corn as a similar group of the Chinese millet and the Indian millet. The Chinese millet contains a summer vigor and becomes as an ingredient of alcoholic drink. And we can find out that $C_4$ type plant (such as corn, Chinese millet, Indian millet, foxtail millet) mostly have a tendency to belong to the food for "Taeumin(太陰人)", because of its high energy efficiency, a flourishing absorption of fertilizing and a strong emission power. The fried corn with a strong summer vigor and a raised feature has a good effect to the treatment of the teethridge disease. And the tea of corn with an warm feature, thanks to its functions of making the stomach and intestines comfortably as well as urination, is a proper food for the 'Taeumin" who is apt to overeat themselves.

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