• Title/Summary/Keyword: Sawyer

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Properties of Powder Electroluminescent Device with $Y_2O_3 and BaTiO_3$ (유전체 종류에 따른 후막 전계발광(EL) 소자의 특성)

  • 이종찬;박춘배;박대희
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 1999.11a
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    • pp.582-585
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    • 1999
  • Electroluminescence is occurred when phosphor is located in electric field. In this paper, we made powder electroluminescent device (PELD) with structured ITO film/Phosphor/Insulator/Silver paste. The transparent electrode was ITO film and green(2704-01) and orange(2702-02) and blue-preen(2703-01) were used as phosphor. The insulator was BaTiO$_3$ and $Y_2$O$_3$, bark electrode was silver paste. To investigate electrical and optical properties of PELDs, EL spectrum, Brightness . Transferred charge density using Sawyer-Towers circuit was measured.

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Characteristics of CaS:Eu,S electroluminescent devices (CaS:Eu,S 전계발광소자의 특성)

  • 조제철;유용택
    • Electrical & Electronic Materials
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    • v.8 no.6
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    • pp.752-758
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    • 1995
  • Red emitting CaS:Eu,S electroluminescent(EL) device prepared at 550.deg. C by an electron-beam evaporation technique, demonstrated luminance of 175cd/m$\^$2/ and efficiency of 0.311m/W with 3kHz drive. Luminance was increased with the increase of applied voltage and frequency. From the results of the PL spectrum and the EL spectrum, the CaS:Eu, S device showed emission peak near 640nm resulted from the transition of EU$\^$2+/ 4f$\^$6/5d.rarw.4f$\^$7/. The capacitance of the phosphor layer from the Sawyer-Tower circuit was 10.5nF/cm$\^$2/.

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Preparation of Paraelectric PLT Thin Films Using Reactive Magnetron Sputtering of Multicomponent Metal Target

  • Kim, H.H.;Sohn, K.S.;Casas, L.M.;Pfeffer, R.L.;Lareau, R.T.
    • Electrical & Electronic Materials
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    • v.11 no.10
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    • pp.53-59
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    • 1998
  • Paraelectric lead landthanum titanate(PLT) thin films have been prepared by a reactive dc magnetron sputtering system using a multicomponent metal target. The surface area control of each element on the target markedly facilitates the fabrication of thin films of complex ceramic compounds. A postdeposition heat-treatment was applied to all as-deposited PLT thin films at annealing temperatures up to 75$0^{\circ}C$ for crystalization. The composition of the PLT(28) thin filmannealed at $650^{\circ}C$ was: Pb, 0.73; La, 0.28; Ti, 0.88; O, 2.9. The dielectric constant and dissipation factor of the thin film(200 nm) at low filed measurements (500 Vcm-1) are 1216 and 0.018, respectively. The charge storage density using a typical Sawyer-Tower circuit with a 500 Hz sine wave was 12.5 $\mu$Ccm-2 at the electric field of 200 kVcm-1.

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Insecticidal Activity of Japanese Pine Sawyer (Monochamus alternatus) and Toxicity Test of Honeybee (Apis mellifera) using 5 Kinds of Neonicotinoids (5종의 네오니코티노이드계 약제에 대한 솔수염하늘소의 살충활성과 꿀벌독성)

  • Cho, Woo Seong;Jeong, Dae-Hoon;Lee, Jae Seon;Kim, Hyun Kyung;Seo, Sang-Tae;Kim, Gil-Hah
    • The Korean Journal of Pesticide Science
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    • v.21 no.1
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    • pp.33-41
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    • 2017
  • Susceptibility and persistence of Japanese pine sawyer, Monochamus alternatus adults, and acute contact toxicity, foliage contact toxicity, and residual toxicity to honeybee, Apis mellifera were evaluated by using 5 kinds of neonicotinoid pesticides. All neonicotinoids pesticides showed over 80% mortality 48 hour after body spray treatment. However, only 2 kinds of acetamiprid ME and acetamiprid+buprofezin showed over 80% mortality in the twig dipping treatment. All of the five neonicotinoides pesticides used in M. alternatus adults showed residual effect of 60-80% mortality, but the efficacy decreased rapidly after 1 day of treatment. Acetamiprid ME showed the lowest toxicity in the acute and foliage contact toxicity test of A. mellifera. The residual toxicity of leaves on A. mellifera was very low in acetamiprid ME and acetamiprid+buprofezin. However, the residual toxicity of all pesticides treatments decreased to 10-30% after 1 day of treatment and further decreased with time. These results indicate that acetamiprid ME among five neonicotinoid agents showed a high insecticidal activity in the M. alternatus adults, while it exhibited relatively low contact and residual toxicity in the A. mellifera. It is thought that acetamiprid ME can be effectively used for the control of the M. alternatus adults as vector of pine wilt disease.

Measurement and Within-tree Distribution of Larval Entrance and Adult Emergence Holes of Japanese Pine Sawyer, Monochamus alternatus(Coleoptera: Cerambycidae) (솔수염하늘소의 유충침입공과 성충탈출공의 측정과 소나무 내 분포)

  • 정영진;이상명;김동수;최광식;이상길;박정규
    • Korean journal of applied entomology
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    • v.42 no.4
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    • pp.315-321
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    • 2003
  • Larval entrance and adult emergence holes of Japanese pine sawyer (Monochamus alternatus), primary vector of pinewood nematode (Bursaphelenchus xylophilus), were measured in dead pine logs from 1999 to 2002. Their distributions within pine log were also analyzed. More numbers of entrance and emergence holes were distributed on crown than trunk part as 56.2 and 27.7 holes/m$^2$, respectively Higher proportions of entrance (27.5%) and emergence holes (22.4%) were distributed on the log with 8 to 10 cm diameter; the larger or the smaller logs had fewer holes. Surface area of entrance hole was 65.8 $\textrm{mm}^2$ and diameter of emergence holes was 7.0 mm in average. Average depth of pupal chamber was 24.8 mm from surface to the bottom of the chamber, and its volume ranged from 200 to 2.000 ㎣ Average distance between entrance and emergence holes on bark surface was 3.3 cm. Gallery length from the beginning of entrance hole to the end of emergence hole was 46.2 mm.

Report on Forests Damaged Due to Cutting Trees Infected by Pine Wilt Disease (소나무재선충 고사목 제거에 따른 산림훼손 보고)

  • Hong, Suk-Hwan;Lee, Soo-Dong
    • Korean Journal of Environment and Ecology
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    • v.29 no.4
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    • pp.590-598
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    • 2015
  • Despite various control methods for pine wilt disease, the disease has been increasing at an alarming rate every year in Korea. Still there is a lack of research on the problems of the current methods used to curb the disease. One main method to control pine wilt disease is fumigation for eliminating the larva of the pine sawyer beetle (Monochamus alternatus) which is known as the vector insect for pine wilt disease. We surveyed and analyzed the amount of destroyed uninfected trees in the fumigated area by studying 32 survey plots ($100m^2$) in Miryang city. The destroyed trees' crown area was estimated by induced regression between root collar area and crown area of the remaining trees (coniferous tree: $R^2=57.4$, deciduous broad-leaved tree: $R^2=63.8$). According to the analysis results, the infected trees (cut trees) were 18.7% and cut trees which were not infected were 35.5% of the total tree population of the study area on the basis of total crown area. In case of pine trees, 8.4% of uninfected trees were cut off but 62% of uninfected deciduous broad-leaved trees including Quercus spp. were affected and damaged during the fumigation process. Since these broad-leaved trees dominate the sub-canopy layer of the forest, this indiscriminate interruption of broad-leaved trees has the adverse effect of depriving the public benefits such as shadow, a cooler weather, controlling humidity, etc.

Adult Morphological Measurements: An Indicator to Identify Sexes of Japanese Pine (솔수염하늘소(Monochamus alternatus) 성충의 형태 측정과 암수 구분)

  • 이상명;정영진;김동수;최광식;김영걸;박정규
    • Korean journal of applied entomology
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    • v.43 no.1
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    • pp.85-89
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    • 2004
  • Numerical measurements were made for fresh weight, body length and width, head width, and color and length of antenna of Japanese pine sawyer, Monochamus alternatus adults, a primary vector of pine wood nematode, Bursaphelenchus xylophilus in Korea. We measured 563 females and 601 males that emerged out of dead pine logs from 2001 to 2002. General linear model analysis showed that measurements of fresh weight, body length, and body width were significantly higher in females than in males. Head width was not significantly different between sexes. Antennal length of males was significantly longer than that of females. For females and males respectively, average fresh weights were 0.305g and 0.277g, body lengths 20.97mm and 19.93mm, body widths 6.52mm and 6.18mm, head widths 3.78mm and 3.70mm, and antennal lengths 31.19mm and 45.49 mm. Antennal length or ratio of antennal length to body length overlapped in some ranges between 2 sexes. Therefore antennal length itself or ratio of antennal length to body length could not be used as a definite criterion to discriminate sexes. However, check on color of the antennae of 4,033 adults revealed without exception that basal part of every segment of flagellum of female antenna was covered with whitish-grey hairs, while whole part of every segment of male flagellum was covered with brownish-black hairs. This characteristics might be a best way to differentiate sex of this species.

Measuring Methods for Two-dimensional Position Referring to the Target Pattern (참조패턴 기반의 2차원 변위 측정 방법론)

  • Jung, Kwang Suk;Lee, Sang Heon;Park, Sung-Jun
    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.22 no.1
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    • pp.77-84
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    • 2013
  • In this paper, we review two-dimensional measuring methods referring to target patterns. The patterns consist of two linearly-repeated patterns or is designed repeatedly in two-dimension. The repeated properties are reflectivity, refractivity, air-gapping distance, capacitance, magnetic reluctance, electrical resistance and sloping gradient, etc. However, the optical methods are generally used for high speed processing and density, and their encoding principles are treated here. In case of two-dimensional pattern, as there is not inherently error between single units encoding the pattern except for the metrology frame errors, the end-effector position of an object accompanying the pattern can be measured with respect of the global frame without via error. Therefore, it is regarded as a substitute for laser interferometer with severe environmental constraints and has been applied to the high-accurate planar actuator.

A Study on Powder Electroluminescent Device through Structure and Thickness Variation (구조 및 두께 변화에 따른 후막 전계발광 소자에 관한 연구)

  • Han, Sang-Mu;Lee, Jong-Chan;Park, Dae-Hee
    • Proceedings of the KIEE Conference
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    • 1998.07d
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    • pp.1379-1381
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    • 1998
  • Powder electroluminescent device (PELD) structured conventionally dielectric and phosphor layer, between electrode and their layer fabricated by screen printing splaying or spin coating method. To promote performance of PELDs, we approached the experiments for different structure and thickness variation of PELD. Thickness variation($30{\mu}m{\sim}130{\mu}m$) was taken. To investigate electrical and optical properties of PELDs, EL spectrum, transferred charge density using Sawyer-Tower's circuit brightness was measured. Variation of structure in PELDs was as follows: WK-1 (ITO/BaTiO3/ZnS:Cu/Silver paste), WK-2 (ITO/BaTiO3/ZnS:Cu/BaTiO3/ZnS:Silver paste), WK-3 (ITO/BaTiO3/ZnS:Cu/BaTiO3/Silver paste), WK-4(ITO/BaTiO3+ZnS:Cu/Silver paste) As a result, structure of the highest brightness appeared WK-4 possessed 60 ${\mu}m$ thickness. The brightness was 2719 cd/$m^2$ at 100V, 400Hz.

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Properties of metal-ferroelectric thin film-silicon(MFS) structure using BaMgF$_{4}$ (BaMgF$_{4}$ 를 이용한 금속-강유전체박막-실리콘(MFS) 구조의 특성)

  • 김광호;김제덕;유병곤
    • Journal of the Korean Institute of Telematics and Electronics A
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    • v.33A no.5
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    • pp.102-107
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    • 1996
  • Use of a rapid thermal annealing (RTA) technique is shown to improve the properties of metal-ferroelectric BaMgF$_{4}$-silicon structures. The fluoride film was deposited in an ultra-high vacuum system at asubstrate temperature of 300$^{\circ}C$. A post-deposition annelaing was conducted for 10 seconds at 600.deg. C in a vacuum of 0.1 Torr, using a home-made RTA apparatus. The results showed that the resistivity of the ferroelectric BaMgF$_{4}$ film from a typical value of 1-2${\times}10^{11}{\Omega}{\cdot}cm$ before the annealing to about 5${\times}10^{13}{\Omega}{\cdot}cm$ and reduce the interface state density of the BaMgF$_{4}$/Si interface to about 8${\times}10^{10}cm^{2}{\cdot}$eV. Ferroelectric hysteresis measurements using a sawyer-tower circuit yielded remanent polarization and coercive field values of about 0.5$\mu$C/cm$^{2}$ and 80 kV/cm, respectively. the typical remanent polarization of the BaMgF$_{4}$ films ont he (100) and (111) oreientated silicon wafers were 0.5 - 0.6 $\mu$C/cm$^{2}$ and that of th efilms on the (110) wafers was 1.2$^{\circ}C$/cm$^{2}$.

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