• 제목/요약/키워드: PDT

검색결과 199건 처리시간 0.028초

Hidden Markov Network 음성인식 시스템의 성능평가에 관한 연구 (A Study on Performance Evaluation of Hidden Markov Network Speech Recognition System)

  • 오세진;김광동;노덕규;위석오;송민규;정현열
    • 융합신호처리학회논문지
    • /
    • 제4권4호
    • /
    • pp.30-39
    • /
    • 2003
  • 본 논문에서는 한국어 음성 데이터를 대상으로 HM-Net(Hidden Markov Network) 음성인식 시스템의 성능평가를 수행하였다. 음향모델 작성은 음성인식에서 널리 사용되고 있는 통계적인 모델링 방법인 HMM(Hidden Markov Model)을 개량한 HM-Net을 도입하였다. HM-Net은 기존의 SSS(Successive State Splitting) 알고리즘을 개량한 PDT(Phonetic Decision Tree)-SSS 알고리즘에 의해 문맥방향과 시간방향의 상태분할을 수행하여 생성되는데, 특히 문맥방향 상태분할의 경우 학습 음성데이터에 출현하지 않는 문맥정보를 효과적으로 표현하기 위해 음소결정트리를 채용하고 있으며, 시간방향 상태분할의 경우 학습 음성데이터에서 각 음소별 지속시간 정보를 효과적으로 표현하기 위한 상태분할을 수행하며, 마지막으로 파라미터의 공유를 통해 triphone 형태의 최적인 모델 네트워크를 작성하게 된다. 인식에 사용된 알고리즘은 음소 및 단어인식의 경우에는 One-Pass Viterbi 빔 탐색을 사용하며 트리 구조 형태의 사전과 phone/word-pair 문법을 채용하고 있다. 연속음성인식의 경우에는 단어 bigram과 단어 trigram 언어모델과 목구조 형태의 사전을 채용한 Multi-Pass 빔 탐색을 사용하고 있다. 전체적으로 본 논문에서는 다양한 조건에서 HM-Net 음성인식 시스템의 성능평가를 수행하였으며, 지금까지 소개된 음성인식 시스템과 비교하여 매우 우수한 인식성능을 보임을 실험을 통해 확인할 수 있었다.

  • PDF

라다클로린으로 매개된 광역학치료에 의한 백색 캔디다 바이오필름의 비활성 (Inactivation of Candida albicans Biofilm by Radachlorin-Mediated Photodynamic Therapy)

  • 권필승
    • 대한임상검사과학회지
    • /
    • 제47권4호
    • /
    • pp.273-278
    • /
    • 2015
  • 이 연구의 목적은 임상 Candida albicans의 바이오필름억제을 위한 Rhadachlorin과 적색발광다이오드를 이용한 광역학치료의 체외적 효과를 평가하고자 하였다. Candida albicans 부유액을 $9{\times}10^8CFU/mL$을 5% 당이 함유된 YNB배지에 준비하였다. Candida albicans의 바이오필름은 96웰 플레이트에 100 uL씩 분주후 3시간 배양하고 상층액을 제거하였다. 각 웰에 $50{\mu}g/mL$ 부터 $0.39{\mu}g/mL$ 농도로 Rhadachlorin을 부착된 세포위에 처리하였다. 30분간 배양 후 빛을 30, 60, 90분을 630 nm 광원의 LED를 이용하여 조사하였고, 이때 각각의 에너지밀도는 14, 29, $43J/cm^2$이였다. 모든 상층액을 제거후에 건조시켰다. 부착된 세포를 safranin O로 염색하였다. 490 nm 파장으로 마이크로플레이트 리더로 흡광도를 측정하였다. 또한, 광감작제포화에 의해 Candida albicans의 형광시그널을 관찰하였다. 결론적으로 확연한 억제는 Rhadachlorin의 농도 $50{\mu}g/mL$과 630 nm LED치료에서 Candida albicans의 바이오필름의 72.5%가 감소되었다. 또한 광감작제 Rhadachlorin은 Candida albicans의 30분에서 충분한 축적을 보였다. 전체적으로 이 결과들은 바이오필름형성의 억제는 Rhadachlorin의 농도에 의존되었다. 이 결과들은 Rhadachlorin과 630 nm LED의 광역학치료는 Candida albicans의 바이오필름 억제가 가능한 것으로 제의된다.

식물유래 섬유자원의 재활용: 탈묵 수율 개선을 위한 신문 지료의 수화 촉진 방안 (Recycling of Plant Fiber Resources: Enhanced Hydration of Newspaper Stock for Decrease of Deinking Reject)

  • 정성현;김중호;주종훈;방재욱
    • 한국펄프종이공학회:학술대회논문집
    • /
    • 한국펄프종이공학회 2011년도 추계학술발표회 논문집
    • /
    • pp.39-41
    • /
    • 2011
  • The recycling rate of recovered paper in Korea is the highest in the world, 92%, but remanufacturing yield is low due to the extremely poor quality of the paper. The poor quality, in turn, influences to the reject amount in deinking process. To increase the yield of old newspaper recycling process, hydrophobic degree of inorganic pigments of deinking stock must be reduced. To determine the hydrophobicity, Pitch Potential Deposit Tester (PDT) was newly designed and applied with respect to the SB latex property of various quality used in Korea; its hydrophobic degree according to Tg, gel content, charge and particle size of latex and optimum designing condition of SB latex. And below are the conclusions: 1. The reason of excessive reject from old newspaper deinking process for total amount of printed ink is loss of inorganic pigments. When lipase, a biochemical catalyst, was applied with the purpose of preventing inorganic pigments loss about more than 70% of total reject weight and promoting hydration of pulp for deinking, deinking process yield of pre flotation secondary stage increased remarkably without any changes of deinking efficiency. 2. Lipase improved deinking stock by cutting ester linkage on surface of hydrophobic materials to promote its hydration. From this, it reached the conclusion that hydration degree of stock exercises significant effect on flotation deinking process yield. 3. Inorganic alkali promotes hydration of deinking stock. But there have been needs for more fundamental measures other than inorganic alkali of promoting hydration for yield improvement. For this, this study intended to find out reasons of chemical properties change on surface of hydrophobic material by change of pH. 4. Pitch Deposit Test (PDT) was performed for understanding principle of why surface of coating flake from OMG is hydrophobic and why it becomes hydrophilic when pH of stock is alkaline. As a result of this test, it is determined that swelling property by change of pH of latex film, which were used as coating adhesive is the reason for hydrophobic change. 5. Hydrophilicity of coating flake increased with hydrophilic pigments. And as more of SB Latex adhesive was used and higher of calcium hardness of stock became, its hydrophilicity decreased. SB Latex adhesive film is reformed by mechanical friction. For having hydrophilicity under neutral pH, strong bruising action such as kneading is required. 6. Because swelling of adhesive film decreases as Tg of SB latex gets lower and mean diameter gets smaller, it shows hydrophobicity under neutral pH. This lowers hydrophilicity of coating flake, which leads to easy elimination with flotation reject on DIP process. Therefore, for improving future flotation yield, it is necessary to develop to use eco-friendly clean SB latex by raising Tg and increasing mean diameter for recycling, and as a result, to reduce excessive loss of coating flake as a reject from deinking process.

  • PDF

The Synthetic Approaches to Modify Methyl (Pyro)pheophorbide a

  • Wang, Jin-Jun;Han, Guang-Fan;Lee, Jong-Cheol;Shim, Young-Key
    • Journal of Photoscience
    • /
    • 제9권2호
    • /
    • pp.178-181
    • /
    • 2002
  • Pyropheophorbide and pheophorbide-photosensitizers as chlorin analogues are promising new compounds for PDT because the chlorin analogues are activated with much longer red light at > 670nm and produce less long-term normal tissue phototoxicity than Photofrin. The various chlorin derivatives can be obtained by moditying peripheral substituted group among which meso-H, vinyl group and exocyclic ring are the most active positions. These characteristics prompted us to introduce various groups for constructing modified pyropheophorbide and pheophorbide a compounds. A stereospecific introduction of various double bonds at 3-position was performed to methylpheophorbide a to give a long hydrophobic moiety and cyclic derivatives. Chlorin-C$_{60}$ dyad and chlorin- $C_{60}$-porphyrin triad also were easily prepared by the reaction of terminal aldehyde of methyl pyropheophorbide a. For the reaction on meso $\delta$-position bromination and Vismeier formylation can occur. N,N-dimethylaminoacrolein also reacted on $\delta$-position and was cyclized to isobacteriochlorin, but other modification has not been succeeded. Exocyclic keto function was also modified to give purpurin derivatives, bicyclic and spiro compounds. In this presentation we report a series of modified pyropheophorbide and pheophorbide a derivatives.s.

  • PDF

백색 점착성 이물질을 측정하기 위한 새로운 시험법 - pH와 칼슘경도의 영향 - (A New Test Method to Evaluate Potential White Pitch Deposit - Influence of pH and calcium hardness -)

  • 신은주;최태호;송봉근;조병욱;류정용
    • 펄프종이기술
    • /
    • 제41권2호
    • /
    • pp.26-33
    • /
    • 2009
  • A new testing method to evaluate the deposition potential of white pitch was developed. The new method involves depositing the potential white pitch particles on the air bubble covered plastic film in the pitch deposit tester (PDT) developed by KRICT and analysing the deposited area of white pitch using an image analyzer. In addition, the effect of two important factors (pH and calcium hardness) on white pitch deposition potential was elucidated. When pH of the coated broke stock was increased from neutral to alkali or the calcium hardness of the stock was decreased, the pitch deposit area was decreased, implying that these two factors have to be controlled during the evaluation of pitch deposition potential. It was found that hydrophobicity of the surface of latex binding films repulped is a key factor influencing white pitch deposition.

NOTES ON THE SPACE OF DIRICHLET TYPE AND WEIGHTED BESOV SPACE

  • Choi, Ki Seong
    • 충청수학회지
    • /
    • 제26권2호
    • /
    • pp.393-402
    • /
    • 2013
  • For 0 < $p$ < ${\infty}$, ${\alpha}$ > -1 and 0 < $r$ < 1, we show that if $f$ is in the space of Dirichlet type $\mathfrak{D}^p_{p-1}$, then ${\int}_{1}^{0}M_{p}^{p}(r,f^{\prime})(1-r)^{p-1}rdr$ < ${\infty}$ and ${\int}_{1}^{0}M_{(2+{\alpha})p}^{(2+{\alpha})p}(r,f^{\prime})(1-r)^{(2+{\alpha})p+{\alpha}}rdr$ < ${\infty}$ where $M_p(r,f)=\[\frac{1}{2{\pi}}{\int}_{0}^{2{\pi}}{\mid}f(re^{it}){\mid}^pdt\]^{1/p}$. For 1 < $p$ < $q$ < ${\infty}$ and ${\alpha}+1$ < $p$, we show that if there exists some positive constant $c$ such that ${\parallel}f{\parallel}_{L^{q(d{\mu})}}{\leq}c{\parallel}f{\parallel}_{\mathfrak{D}^p_{\alpha}}$ for all $f{\in}\mathfrak{D}^p_{\alpha}$, then ${\parallel}f{\parallel}_{L^{q(d{\mu})}}{\leq}c{\parallel}f{\parallel}_{\mathcal{B}_p(q)}$ where $\mathcal{B}_p(q)$ is the weighted Besov space. We also find the condition of measure ${\mu}$ such that ${\sup}_{a{\in}D}{\int}_D(k_a(z)(1-{\mid}a{\mid}^2)^{(p-a-1)})^{q/p}d{\mu}(z)$ < ${\infty}$.

Synthesis and Characterization of Upconversion Nanoparticles for Cancer Therapy

  • 최승유;김보배;김은비;이승우;전선아;박태정
    • 한국진공학회:학술대회논문집
    • /
    • 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
    • /
    • pp.420.2-420.2
    • /
    • 2016
  • Various fields have been paid attention to upconversion nanoparticles (UCNPs) because of its unique optical properties. Moreover, to use the UC luminescent techniques through cell images for identified apoptosis/necrosis of cancer cells have been performed. They have been studied for a versatile biomedical application such as a biosensing tool, or delivery of active forms of medicines inside living cells. UCNPs have distinctive characteristics such as photoluminescence, special emission, low background fluorescence signal and good colloidal stability, which have many advantages compared with the organic dyes and quantum dots. UCNPs have not only a great potential for imaging (UC luminescence) but also therapies (photo-thermal therapy, PTT and photo-dynamic therapy, PDT) in cancer diagnostics. Therefore, we report the enhancement of upconversion red emission in NaYF4:Yb3+,Er3+ nanoparticles, synthesized via solid-state method with the thermal decomposition of trifluoroacetate as precursors and organic solvent at a high boiling point. The UCNPs have an emission in the field of near infrared wavelength, cubic shape and nano-size in length. In this study, we will further investigate it for cancer therapy with NIR optical detection onto the solid substrate.

  • PDF

농도가 진한 매질에서 광증감제에 의한 광학적 파라미터측정에 관한 연구 (A Study on the Measurements of Optical Parameters in Photosensitizer by Light Scattering)

  • 김기준;이주엽
    • 한국응용과학기술학회지
    • /
    • 제28권1호
    • /
    • pp.102-108
    • /
    • 2011
  • The study of wave propagation and scattering in biological media has become increasingly important in recent years. The propagation of light within tissues is an important problem that confronts the dosimetry of therapeutic laser delivery and the development of diagnostic spectroscopy. In the clinical application of photodynamic therapy(PDT) and in photobiology, the photon deposition within a tissue determines the spatial distribution of photochemical reactions. Scattered light is measured as a function of the distance (r) between the axis of the incident beam and the detection spot. Consequently, knowledge of the photosensitizer(Chlorophyll-a) function that characterizes a phantom is measured. To obtain the results of scattering coefficients(${\mu}s$) of a turbid material from diffusion described by experimental approach. It was measured the energy fluency of photon radiation at the position of penetration depth. From fluorescence experimental method obtained the analytical expression for the scattered light as the values of $(I/I_o)_{wavelength}$ vs the distance between the center of the incident beam and optical fiber in terms of the condition of "in situ spectroscopy(optically thick)" and real time by fluorometric measurements. The result was compromised with transport of intensities though a random distribution of scatters.

In Vitro에서 광증감제에 의한 광학적 영향에 관한 연구 (A Study on the Optical Influence by Photosensitizer in Vitro)

  • 김기준;성기천
    • 한국응용과학기술학회지
    • /
    • 제22권2호
    • /
    • pp.182-190
    • /
    • 2005
  • The propagation of light radiation within tissues is an important problem that confronts the dosimetry of therapeutic laser delivery and the development of diagnostic spectroscopy. In the clinical application of photodynamic therapy(PDT) and in photobiology, the photon deposition within a tissue determines the spatial distribution of photochemical reactions. Scattered light is measured as a function of the distance (r) between the axis of the incident beam and the detection spot. Consequently, knowledge of the photosensitizer(Chlorophyll-a) function that characterizes a phantom is important. To obtain the results of scattering coefficients(${\mu}s$) of a turbid material from diffusion described by experimental approach. It was measured the energy fluency of photon radiation at the position of penetration depth. From fluorescence experimental method obtained the analytical expression for the scattered light as the values of $(I\;/I_o)_{wavelength}$ vs the distance between the center of the incident beam and optical fiber in terms of the condition of "in situ spectroscopy(optically thick)" and real time by fluorometric measurements.

상태레벨 공유를 이용한 HM-Net 적응화 시스템의 성능평가에 관한 연구 (A Study on Performance Evaluation of HM-Net Adaptation System Using the State Level Sharing)

  • 오세진;김광동;노덕규;황철준;김범국;김광수;성우창;정현열
    • 대한전자공학회:학술대회논문집
    • /
    • 대한전자공학회 2003년도 신호처리소사이어티 추계학술대회 논문집
    • /
    • pp.397-400
    • /
    • 2003
  • 본 연구에서는 KM-Net(Hidden Markov Network)을 다양한 태스크에의 적용과 화자의 특성을 효과적으로 나타내기 위해 HM-Net 음성인식 시스템에 MLLR(Maximum Likelihood Linear Regression) 적응방법을 도입하였으며, HM-Net 학습 알고리즘을 개량하여 회귀클래스 생성방법을 제안한다. 제안방법은 PDT-SSS(Phonetic Decision Tree-based Successive State Splitting) 알고리즘의 문맥방향 상태분할에 의한 상태레벨 공유를 이용한 방법으로 새로운 화자로부터 문맥정보와 적응화 데이터의 발성 양에 의존하여 결정된 많은 적응 파라미터들을(평균, 분산) 자유롭게 제어할 수 있게 된다. 제안방법의 유효성을 확인하기 위해 국어공학센터(KLE) 452 음성 데이터와 항공편 예약관련 연속음성을 대상으로 인식실험을 수행한 결과, 전체적으로 음소인식의 경우 평균 34-37%, 단어인식의 경우 평균 9%, 연속음성인식의 경우 평균 7-8%의 인식성능 향상을 각각 보였다. 또한 적응화 데이터의 양에 따른 인식성능 비교에서, 제안방법을 적용한 인식 시스템이 적응 데이터의 양이 적은 경우에도 향상된 인식률을 보였으며. 잡음을 부가한 음성에 대한 적응화 실험에서도 향상된 인식성능을 보여 MLLR 적응방법의 특성을 만족하였다. 따라서 MLLR 적응방법을 도입한 HM-Net 음성인식 시스템에 제안한 회귀클래스 생성방법이 유효함을 확인한 수 있었다.

  • PDF