• Title/Summary/Keyword: Optical density

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Effects of Auricular Acupuncture on NADPH-diaphorase Neurons in Brain Cortex of Fasted Rats (이침자극(耳鍼刺戟)이 절식(絶食) Stress로 인(因)한 흰쥐 대뇌피질(大腦皮質)의 NADPH-diaphorase 신경세포(神經細胞)에 미치는 영향(影響))

  • Lee, Jung-hyun;Kim, Ee-Hwa;Lee, Eun-yong
    • Journal of Acupuncture Research
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    • v.18 no.2
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    • pp.79-90
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    • 2001
  • Objective : The aim of the present study is to investigate whether stimulating a specific auricular point(胃點) is effect on suppression of appetite. Methods : This study evaluated the changes of Reduced-Nicotinamide-Adenine-inucieotide-Phosphate-diaphorase(NADPH-d)-positive neurons using a histoehemical method. Staining intensities of NADPH-d-positive neurons were assessed in a quantitative fashion using a microdensitometrical method based on optical density by means of an image analyzer. Results : The results show as follows ; 1. In the RSG/RSA, FRI/FR2, HL, PAR1 area, The optical density of NADPH-d-positive neurons of fasted group was significantly decreased in comparison to fed group. 2. In most cortical area, It was not significant statistically, But the optical density of NADPH-d-positive neurons of fed with auricular acupuncture group was decreased in comparison to fed group. 3. In most cortical area, It was not significant statistically, But fasted with auricular acupuncture group increased the optical density of NADPH-d-positive neurons comparison to fasted group. Conclusions : We conclude that stimulating the specific auricular points is able to effect on NO(Nitric Oxide)-expression in the brain cortex of sprague dawley rats, The results suggest that auricular acupuncture may be useful for controlling obesity.

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Nonlinearity of semiconductor optical amplifier and gain-clamping effects of Iaser-injected semiconductor optical amplifier in wavelength division mulitiplexing (파장 다중 광통신에서의 반도체 광증폭기의 비선형성과 연속파동 레이저가 입사된 반도체 광증폭기의 이득고정 효과)

  • 김동철;유건호;김형문;주흥로;한선규;주관종
    • Korean Journal of Optics and Photonics
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    • v.11 no.1
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    • pp.37-42
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    • 2000
  • We have numerically solved rate-equations of semiconductor optical amplifier (SOA) to understand the characteristics of SOA. The rate-equations we have used can describe injection carrier density, amplified spontaneous emission and signal photon density in spatial and time domain by dividing the cavity into multi-section. We have investigated injection carrier density, amplified spontaneous emission and signal photon density as a function of position and time in the case of single channel input in the form of square pulse. Also we have analyzed the non-linear phenomena of SOA in the case of injecting multi-channel wavelengths as in WDM. Intermodulation distortion (IMD) caused by beat among channels has significant effects on the signal distortion as the channel spacing becomes narrower, and channel crosstalk becomes larger as the power of signals increases. In the case of the injection of another CW laser whose wavelength is far enough from the signal wavelengths, the crosstalk and the output signal distortion can be significantly reduced. duced.

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The Experimental Study for the Smoke Optical Density and Toxic Gases of Sandwich Panel Insulations(Single Chamber Method) (샌드위치패널 단열재의 연기농도 및 연소독성가스에 대한 실험적 연구(연소챔버법))

  • Park, Soo-Young;Lee, Woo-Seok;Yeo, Han-Seung;Im, Hong-Soon
    • Fire Science and Engineering
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    • v.20 no.4 s.64
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    • pp.26-32
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    • 2006
  • Nowadays in Korea, KS F 2271 has been using for the test of fire safety performance of sandwich panels. Smoke toxicity test is the test for the toxicity evaluation of smoke and hazardous gas, caused by combustion of building materials and finishing materials. Smoke toxicity can be evaluated by the mean incapacitation time of mice; however this method is not a quantitative way. This test result can be influenced by the health status of mice and test condition. Specific optical density can be quantitatively measured by ISO 5659-2 single chamber method and toxic gases can be quantitatively measured by FTIR analysis. In this study, specific optical density of sandwich panel insulations, which are widely used in Korea, were tested using the ISO 5659-2 single chamber test method and compared with each test. Also, in the second test of three tests for each specimen, FTIR analysis was performed and quantitative test results(HCl, $NO_2$, etc) were compared with each test result.

Measurement of Birefringence Distribution in Optical Disk Substrates Fabricated by Injection-Compression Molding (사출압축성형을 통한 광디스크 기판 성형 및 복굴절의 측정)

  • 김종성
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 1999.03b
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    • pp.218-224
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    • 1999
  • It is necessary to improve mechanical and optical properties in the optical disk substrates as the information storage devices with high storage density using short wavelength laser are being developed. Injection compression molding is regarded as the most suitable process to manufacture optical disk substrates with high is regarded as the most suitable process to manufacture optical disk substrates with high dimensional accuracy low residual stresses and superb optical properties In the present study polycarbonate optical disk substrates were fabricated by injection compression molding and the birefringence regarded as one of the most important optical properties for optical disk is measured. The effects of various processing conditions upon the development of birefringence distribution were examined experimentally. It was found that the value of the birefringence distribution were very sensitive to the mold wall temperature history and the variance of the birefringence distribution in the radial direction was affected by the level of the packing and the compression pressure.

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Optimal Conditions of Aerosol Flow Generation for High-density and Uniform Fog Screen (고밀도 균일 안개스크린을 위한 에어로졸 유동의 최적 생성조건)

  • Shin, Dongsoo;Song, Wooseok;Kim, Jinwon;Kim, Woojin;Koo, Jaye
    • Journal of ILASS-Korea
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    • v.22 no.1
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    • pp.13-21
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    • 2017
  • The fog screen is a device projecting the media to the aerosol flow field. As major parameters to generate dense and steady fog screen, shear stress, optical blockage ratio and SMD were obtained result through experiment. The micro droplet was generated by the piezo oscillation element, and the aerosol flow mixed with an air flow was sprayed into the vertical direction from the top of the fog screen through the 280 mm slot. For produce a dense, uniform fog screen, the shear effect, optical blockage ratio and SMD between aerosol and air curtain were measured. The minimum and maximum shear stress conditions were selected and it was confirmed that the optical transmission deviation of the aerosol flow field was small when the aerosol and air curtain flow rates were changed. When the aerosol and air curtain flow power were 18 V (1.51 m/s) and 24 V (2.55 m/s), respectively, under the condition of the minimum shear stress and laminar flow, the optical blockage ratios with the spray length were small, and it produced a most stable and high density uniform fog screen by injecting a constant of $10{\mu}m$ or less.

Effects of Gd2O3 Addition on Optical and Electrical Properties of MgO Films as a Protective Layer for AC PDPs (Gd2O3 첨가에 따른 AC PDP 보호막용 MgO 박막의 광학적.전기적 특성)

  • Kim, Chang-Il;Lim, Eun-Kyeong;Park, Young-Jun;Lee, Young-Jin;Paik, Jong-Hoo;Choi, Eun-Ha;Juang, Seok;Kim, Jeong-Seok
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.20 no.7
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    • pp.620-625
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    • 2007
  • The effects of $Gd_2O_3$ addition and sintering condition on optical and electrical properties of MgO films as a protective layer for AC plasma display panels were investigated. Doped MgO films prepared by the e-beam evaporation have a higher ${\Upsilon}$ (secondary electron emission coefficient) than pure MgO protective layer. Relative density and grain size increased with amount of $Gd_2O_3$ up to 100 ppm and then decreased further addition. These results showed that discharge properties and optical properties of MgO protective layers seemed to be closely related with microstructure factors such as relative density and grain size. Good optical and electrical properties of ${\Upsilon}$ of 0.138, surface roughness of 5.77 nm and optical transmittance of 95.76 % were obtained for the MgO+100 ppm $Gd_2O_3$ protective layer sintered at $1700^{\circ}C$ for 5 hrs.

Evaluation of soft iterative decoder with run length limited code in optical storage system

  • 김기현;한성휴;심재성;박현수;박인식
    • Proceedings of the IEEK Conference
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    • 2002.06e
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    • pp.99-102
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    • 2002
  • In this work, we evaluated the performance of soft iterative decoder with soft block decoder in optical storage system. Because optical storage system requires run- length limited code in general, adaptation of the soft decoders such as turbo code or LDPC(low density parity check code) is difficult without soft block decoders. The performance of the overall optical detection system is evaluated and the simplified channel detection is also proposed.

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Super Resolution Readout in Near Field Optical Data Storage System (근접장 광 기록 재생 시스템에서의 초해상 재생 현상 확인)

  • Lee, Jin-Kyung;Jeong, An-Sik;Shin, Jong-Hyun;Kim, Joo-Ho;Lee, Kyung-Geun;Kim, Joong-Gon;Park, No-Cheol;Park, Young-Pil
    • Transactions of the Society of Information Storage Systems
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    • v.4 no.1
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    • pp.1-5
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    • 2008
  • Super-resolution near-field structure (super-RENS) technology and solid immersion lens (SIL) based near-field (NF) technology have been expected as promising approaches to increase data capacity or areal density of optical disc. Super-RENS technology has been studied until now using mainly numerical aperture (NA) of 0.85 far-field optical system and possibility of tangential data density increment have been presented. NF technology has been studied with NA over 1 and presented demonstration of removable performance. To achieve much higher density, approach to increase NA of super-RENS by NF technology (Near-Field Super-Resolution, NFSR) can be a candidate and we think this technology would be advantageous compared to wavelength reduction or much higher NA increment of NF technology or much smaller effective optical spot size reduction of far-field super-resolution technology. In this paper we present readout result of ROM media having monotone pits using NF optical system with wavelength of 405nm and NA of 1.84 surface type SIL. GeSbTe material was used for super resolution active layer and pit length is 37.5nm which is shorter than resolution limit 55nm. We present the feasibility of NFSR technology by confirming the CNR threshold according to readout power (Pr) and CNR 33dB over threshold Pr.

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Difference in NOS between 2 Hz and 100 Hz EA in cerebral cortex, brain stem and cerebellum of spontaneously hypertensive rats (전침자극이 Spontaneously Hypertensive Rat의 대뇌겉질, 뇌줄기, 소뇌 부위의 Nitric Oxide Synthase 신경세포에 미치는 영향)

  • Kim, Jong-In;kim, Yong-Suk;Kim, Chang-Hwan
    • Journal of Acupuncture Research
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    • v.18 no.4
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    • pp.116-124
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    • 2001
  • Background and Objetive : The aim of this study was to investigate the effect of various electroacupuncture stimulation on NADPH-diaphorase in cerebral cortex, brain stem, cerebellum of spontaneously hypertensive rats. Materials and Methods : We evaluated the changes of NADPH-d-positive neurons using a histochemical method. The staining intensity of NADPH-d-positive neurons was assessed in a quantitative fashion using a microdensitometrical method based on optical density by means of an image analyzer. Results and Conculsion : The average optical density of NADPH-d-positive neurons of 100 Hz (bipolar square wave 0.2 ms duration and 100 Hz frequency) electroacupuncture treatment group significantly increased in most cortical areas comparison between the manual acupuncture and 2 Hz (bipolar square wave 0.2 ms duration and 2 Hz frequency) electroacupuncture groups. In the brain stem, the optical density of NADPH-d-positive neuron at only superficial gray layer of the superior colliculus area was same as cerebral cortex. We conclude that the morphological evidence for NADPH-d-positive neurons may be have regional change in cerebral cortex brain stem and cerebellum according to various electroacupuncture stimulations.

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Isolation and identification of Lactobacillus inhibiting the production of halitosis by anaerobic bacteria (구취를 유발하는 혐기성 세균의 증식을 억제하는 유산 간균의 분리 및 동정)

  • Kim, Mi-Hyung;Kim, Seon-Mi
    • Journal of Korean society of Dental Hygiene
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    • v.4 no.2
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    • pp.153-163
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    • 2004
  • There are normal inhabitants doing medically useful functions in the body. There are many kinds of bacteria performing specific functions in the oral cavity. Two strains of lactic acid bacteria were isolated from normal inhabitants of children 's oral cavity, which inhibited the the production of halitosis by anaerobic bacteria. The authors identified the isolates by the lest using API 50 CHL medium kit. 1. Two isolates were Gram-positive bacilli and produced hydrogen peroxide. 2. The optical density was 1.286 in the supernatant of Fusobacterium nucleatum after vortexing for 30 minutes, whereas in the supernatant of combined Fusobacterium nucleatum and each isolate, they were reduced to 0.628 and 0.497, which the percentages of coaggregation between them were 29.4% and 57.8%, respectively. 3. The optical density of Fusobacterium nucleatum precipitate was 1.794 in the culture media containing cysteine and $FeSO_4$, being reduced to 1.144 and 0.915 in the coaggregated precipitates of Fusobacterium nucleatum and each isolate. 4. The optical density of Porphyromonas gingivalis precipitate was 1.932 in the culture media, being reduced to 1.170 and 1.266 in the coaggregated precipitates of Porphyromonas gingivalis and each isolate. 5. When two isolates were tested with API 50 CHL medium kit, those were identified as Lactobaciallius salivarius and Lactobacillus delbrueckii subsp. lactis.

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