• 제목/요약/키워드: HAL

검색결과 266건 처리시간 0.032초

비대칭비구면 렌즈 사출 코어용 6:4 황동 초정밀 형상 가공 (Ultra Precision Machining of Injection Mold Core for Asymmetric Aspheric Lens using 6:4 Brass)

  • 이동길;구할본;김정호
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
    • /
    • pp.427-427
    • /
    • 2007
  • The global applications of aspherics surfaces will expand rapidly on the electronics, optical components, communications, aerospace, defense, and medical optics devices etc. Especially, Asymmetric aspheric prism lens is one of the important parts in HMD(Head Mounted Display) because it affects dominantly on the optical performance of HMD. The mold core is the most important device to produce the plastic lenses by injection molding method. In this study, the mold cores for asymmetric aspheric prism lens were processed using fly-cutting method which is kind of the ultra precision processing and form accuracy and surface roughness of the cores were measured.

  • PDF

고분자 버퍼층을 갖는 $LiNbO_3$ 집적 광디바이스 ($LiNbO_3$ integrated optic devices with an UV-curable polymer buffer layer)

  • 정운조;김성구;김대중;김종욱;박계춘;구할본
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 2002년도 추계학술대회 논문집 전기물성,응용부문
    • /
    • pp.230-233
    • /
    • 2002
  • A new lithium niobate optical modulator with a polymer buffer layer on Ni in-diffused optical waveguide is proposed for the fist time, successfully fabricated and examined at a wavelength of 1.3 ${\mu}m$. The experimental results show that the measured half-wave voltage is of ${\sim}10$ V and the total measured fiber-to-fiber insertion loss is of ${\sim}-6.4$ dB for a 40 mm long waveguide at a wavelength of 1.3 ${\mu}m$, respectively.

  • PDF

Tin Oxide-flyash Composite 전극의 리튬 이온 Intercalation 메카니즘과 임피던스 특성에 관한 연구 (A Study on the Impedance Characteristics and Mechanisms of Li Intecalation on the Tin Oxide-flyash Composite Electrodes)

  • 구할본;김종욱
    • 한국전기전자재료학회논문지
    • /
    • 제17권11호
    • /
    • pp.1224-1229
    • /
    • 2004
  • The purpose of this study is to research and develop tin oxide-flyash composite for lithium Ion polymer battery. Tin oxide is one of the promising material as a electrode active material for lithium Ion polymer battery (LIPB). Tin-based oxides have theoretical volumetric and gravimetric capacities that are four and two times that of carbon, respectively. We investigated cyclic voltammetry, AC impedance and charge/discharge cycling of SnO$_2$-flyash/SPE/Li cells. The first discharge capacity of SnO$_2$-flyash composite anode was 639 mAh/g. The discharge capacity of SnO$_2$-flyash composite anode was 563 and 472 mAh/g at 6th and 15th cycle, respectively. The SnO$_2$-flyash composite anode with PVDF-PMMA-PC-EC-LiClO$_4$ electrolyte showed good capacity with cycling.

에너지전달을 이용한 가시광 Light Source의 발광특성에 관한 연구 (Study on the Emission Properties of Visible Light Source using Energy Transfer)

  • 구할본;김주승
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
    • /
    • pp.486-489
    • /
    • 2003
  • Red organic electroluminescent(EL) devices based on poly(N-vinylcarbazole)(PVK) and tris(8-hydroxyquinorine aluminum)($Alq_3$) doped with red emissive material, 4-(dicyanomethylene)-2-t-butyl-6-(1,1,7,7-tetramethyljulolidyl-9-enyl)4H-pyran(DCJTB), poly(3-hexylthiophene)(P3HT), Rubrene and 4-dicyanomethylene-2-methyl-6[2-(2,3,6,7-tetrahydro-1H,5H-benzo-[i.j])quinolizin-8yl)vinyl-4H-pyran(DCM2) were fabricated. We examine the energy transfer from $Alq_3$ to DCJTB, P3HT, Rubrene and DCM2 by comparing between the PL and EL spectrum. The maximum peak PL intensities were achieved when the doping concentration of DCJTB, DCM2, P3HT and Rubrene has 5, 1, 0.5, 2wt%, respectively. The maximum luminance of device using DCJTB showed $594\;cd/m^2$ at 15V.

  • PDF

리튬 폴리머 전지용 $LiFe_xMn_{1-x}PO_4$ 정극활물질의 전기화학적 특성 (The electrochemical properties of $LiFe_xMn_{1-x}PO_4$ cathode materials for lithium polymer batteries)

  • 전대규;구할본
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
    • /
    • pp.424-425
    • /
    • 2005
  • The purpose of this study is to research and develop $LiFe_xMn_{1-x}PO_4$ cathode for lithium polymer batteries. $LiFe_xMn_{1-x}PO_4$ cathode active materials were prepared using a solid-state reaction by adding carbon black to the synthetic precursors. We investigated cyclic voltammetry and charge/discharge cycling of $LiFe_xMn_{1-x}PO_4$/SPE/Li cells. The discharge capacity of $LiFe_{0.5}Mn_{0.5}PO_4$ was l26mAh/g and 110mAh/g at 1st and 10th cycle.

  • PDF

수열법을 이용한 $LiMnPO_4$의 충방전 특성 (Charge-discharge characteristics of $LiMnPO_4$ prepared by hydrothermal synthesis)

  • 공명철;구할본
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
    • /
    • pp.420-421
    • /
    • 2005
  • $LiMnPO_4$ particle were prepare by a hydrothermal reaction. The particles prepared by adding polyethylene glycol(PEG) and carbon to the starting reaction solution were fine crystalline in the range of 200-300nm. The discharge capacity of the sample as a lithium secondary battery was $25mAhg^{-1}$ at $0.04mAcm^{-2}$, larger than that of the sample prepared by the hydrothermal method without PEG and carbon.

  • PDF

A novel urine-activated microbattery

  • Jin, Bo;Gu, Hal-Bon
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
    • /
    • pp.396-397
    • /
    • 2006
  • The novel urine-activated microbatteries have been successfully demonstrated. In this microbattery, a magnesium (Mg) layer and copper chloride (CuCl) in the filter paper are used as the anode and the cathode, respectively. A stack consisting of a Mg layer, CuCl-doped filter paper and a copper (Cu) layer sandwiched between two plastic layers is hot-pressed into the microbatteries at $100^{\circ}C$. The microbatteries can be activated by adding a droplet of human urine. The experimental results show that the microbattery can deliver a maximum voltage of 1.4 V and maximum power of 1.96 mW for the $1\;k{\Omega}$ load resistor.

  • PDF

『황제내경(黃帝內經)』에서의 몸과 건강(健康)에 대한 연구(硏究) (A Study of heathy condition in Hunagdineijing)

  • 오재근;김용진
    • 한국의사학회지
    • /
    • 제20권2호
    • /
    • pp.3-17
    • /
    • 2007
  • The term '健康(heathy condition)' does not appear in East Asian medical classics. Its root comes from the ancient word 'hal' which can be translated as 'hale', 'whole', 'sound in wind and limb', and it means 'the physical state is flawless, whole, satisfactory, and strong'. The Japanese translated it into the Chinese letters 건강 in the 19th century and this was spread during the Japanese occupation era. This study is an attempt to explore what "huangdineijing" (the most representative medical documents of East Asian medicine) mentions about healthy condition, which is as a term to express the body's ideal state and what other concepts exist that correspond to 健康.

  • PDF

Design and development of an automated all-terrain wheeled robot

  • Pradhan, Debesh;Sen, Jishnu;Hui, Nirmal Baran
    • Advances in robotics research
    • /
    • 제1권1호
    • /
    • pp.21-39
    • /
    • 2014
  • Due to the rapid progress in the field of robotics, it is a high time to concentrate on the development of a robot that can manoeuvre in all type of landscapes, ascend and descend stairs and sloping surfaces autonomously. This paper presents details of a prototype robot which can navigate in very rough terrain, ascend and descend staircase as well as sloping surface and cross ditches. The robot is made up of six differentially steered wheels and some passive mechanism, making it suitable to cross long ditches and landscape undulation. Static stability of the developed robot have been carried out analytically and navigation capability of the robot is observed through simulation in different environment, separately. Description of embedded system of the robot has also been presented and experimental validation has been made along with some details on obstacle avoidance. Finally the limitations of the robot have been explored with their possible reasons.

Dislocation densities of CMP processed sapphire wafers for GaN epitaxy

  • 황성원;남정환;신귀수;김근주;서남섭
    • 한국반도체및디스플레이장비학회:학술대회논문집
    • /
    • 한국반도체및디스플레이장비학회 2003년도 춘계학술대회 발표 논문집
    • /
    • pp.18-22
    • /
    • 2003
  • The sapphire wafers for blue light emitting devices were manufactured by the implementation of the surface machining technology based on micro-tribology. This process has been performed by grinding, lapping and polishing. The surfaces of sapphire wafers were mechanically affected by residual stress and surface default. This mechanical stress and strain can be cured by thermal anneal ing process. The sapphire crystalline wafers were annealed at $1100~1400^{\circ}C$ and then characterized by double crystal X-ray diffraction. The sample showed good quality of crystalline wafer surface wi th full width at hal f maximum of 16 arcsec for the 4-hour heat-treatment at $1300^{\circ}C$.

  • PDF