• 제목/요약/키워드: classical

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인천지역에서 발생한 돼지콜레라의 역학적 특성 (Characteristics of outbreak for the classical swine fever (CSF) at Incheon metropolitan area in 2002)

  • 권효정;변재원;이정구;김경호;박은정;이성모;황현순
    • 한국동물위생학회지
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    • 제26권1호
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    • pp.1-9
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    • 2003
  • The aim of this survey was to investigate the characteristics of outbreak farm determined as the classical swine fever(CSF) at Gangwha-gun and Seo-gu, Incheon metropolitan area from October 7 to November 25 in 2002. Sixty pigs in six different farms were confirmed to the CSF and a total of 9,106 pigs containing 3,194 related epidemiologically was slaughtered to stop spreading of the disease. Clinical signs of pigs diagnosed with the CSF were high fever, anorexia, depression, paralysis of hindlimbs, cyanosis, etc and gross lesions were typically represented with hemorrhage of submandibular and superficial lymph node, infarction of spleen, and petechial (ecchymotic) hemorrhage of kidney and skin. But some outbreak farms had not shown remarkable symptoms, so they were confused with other bacterial diseases. White blood cell (WBC) counts, the classical swine fever virus(CSFV) antigen and antibody enzyme linked immunosorbent assay(ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR) results about six farms indicated that total 60 pigs were infected with the CSFV. Although the origin and infection route of the CSFV were not clear, but the transmissions between farms were mainly through indirect contact such as the movement of farm personal and vehicles from outbreak farm.

빛의 세기 및 위상 요동에 나타나는 진공 효과 (Effect of vacuum on amplitude and phase fluctuation)

  • 노재우;김기식
    • 한국광학회지
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    • 제7권3호
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    • pp.219-226
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    • 1996
  • 빛의 입자 파동 이중성을 수용하는 양자 광학은 때때로 파동성에만 바탕을 둔 고전 광학과 상이한 결과를 보여준다. 본 논문에서는 빛이 빛살 가르개를 통과하면서 그 세기와 위상에 대한 요동이 어떻게 변화하는가를 고찰하고 고전 이론과 양자 이론이 보이는 차이점을 기술하였다. 측정 가능량을 나타내는 세가지 연산자를 통하여 고전 이론과는 달리 양자 이론에서는 빛살 가르개를 통과한 후 빛의 세기와 위상에 대한 불확실도가 증가함을 보이고 이를 진공 요동에 의한 효과로 정량적으로 분석하였다. 한편 진공효과를 배제하는 과정으로서 정규 차례를 따르는 연산자에 대한 기대치는 고전적 파동 이론의 결과와 일치함을 보임으로써 고전적 파동 이론과의 대응성을 추구하였다. 또한 이러한 결과로부터 진공 효과를 포함하는 실제의 측정 위상과 고전 이론에 대응하는 추측 위상의 구분 및 그 관계를 보였다.

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강제 공진형 EMI 다이폴 안테나에 대한 시험장 감쇠량 이론 곡선 (Theoretical Curve of Classical Site Attenuation for Forced Resonant Type EMI Dipole Antennas)

  • 주창현;박은정;김기채
    • 한국전자파학회논문지
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    • 제16권6호
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    • pp.571-579
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    • 2005
  • 본 논문은 80 MHz 이하의 주파수 대역에서 사용하기 위해 제안된 강제 공진형 EMI 다이폴 안테나에 대한 시험장 감쇠량 이론 곡선을 계산하고 있다. 이론 해석으로서는 안테나에 흐르는 전류 분포에 관한 연립 적분 방정식을 유도하고 구분 정현 함수를 사용한 Galerkin의 모멘트 법으로 그 해를 구하여 시험장 감쇠 량을 검토하고 있다. 그 결과, 강제 공진형 EMI 다이폴 안테나는 50 MHz 이하 주파수 대역의 수평 편파 시험장 감쇠량 측정에 유용하게 사용할 수 있음을 확인할 수 있었다. 제시된 시험장 감쇠량 이론치는 강제 공진형 EMI 다이폴 안테나를 사용하여 야외 시험장의 적합성을 평가할 때 기준 이론 곡선으로 활용할 수 있다.

Performance Degradation Due to Particle Impoverishment in Particle Filtering

  • Lim, Jaechan
    • Journal of Electrical Engineering and Technology
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    • 제9권6호
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    • pp.2107-2113
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    • 2014
  • Particle filtering (PF) has shown its outperforming results compared to that of classical Kalman filtering (KF), particularly for highly nonlinear problems. However, PF may not be universally superior to the extended KF (EKF) although the case (i.e. an example that the EKF outperforms PF) is seldom reported in the literature. Particularly, PF approaches show degraded performance for problems where the state noise is very small or zero. This is because particles become identical within a few iterations, which is so called particle impoverishment (PI) phenomenon; consequently, no matter how many particles are employed, we do not have particle diversity regardless of if the impoverished particle is close to the true state value or not. In this paper, we investigate this PI phenomenon, and show an example problem where a classical KF approach outperforms PF approaches in terms of mean squared error (MSE) criterion. Furthermore, we compare the processing speed of the EKF and PF approaches, and show the better speed performance of classical EKF approaches. Therefore, PF approaches may not be always better option than the classical EKF for nonlinear problems. Specifically, we show the outperforming result of unscented Kalman filter compared to that of PF approaches (which are shown in Fig. 7(c) for processing speed performance, and Fig. 6 for MSE performance in the paper).

Bending of a cracked functionally graded nanobeam

  • Akbas, Seref Doguscan
    • Advances in nano research
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    • 제6권3호
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    • pp.219-242
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    • 2018
  • In this study, static bending of an edge cracked cantilever nanobeam composed of functionally graded material (FGM) subjected to transversal point load at the free end of the beam is investigated based on modified couple stress theory. Material properties of the beam change in the height direction according to exponential distributions. The cracked nanobeam is modelled using a proper modification of the classical cracked-beam theory consisting of two sub-nanobeams connected through a massless elastic rotational spring. The inclusion of an additional material parameter enables the new beam model to capture the size effect. The new non-classical beam model reduces to the classical beam model when the length scale parameter is set to zero. The considered problem is investigated within the Euler-Bernoulli beam theory by using finite element method. In order to establish the accuracy of the present formulation and results, the deflections are obtained, and compared with the published results available in the literature. Good agreement is observed. In the numerical study, the static deflections of the edge cracked FGM nanobeams are calculated and discussed for different crack positions, different lengths of the beam, different length scale parameter, different crack depths, and different material distributions. Also, the difference between the classical beam theory and modified couple stress theory is investigated for static bending of edge cracked FGM nanobeams. It is believed that the tabulated results will be a reference with which other researchers can compare their results.

CTX Prophages in Vibrio cholerae O1 Strains

  • Kim, Eun Jin;Lee, Dokyung;Moon, Se Hoon;Lee, Chan Hee;Kim, Dong Wook
    • Journal of Microbiology and Biotechnology
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    • 제24권6호
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    • pp.725-731
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    • 2014
  • The classical biotype strains of the Vibrio cholerae O1 serogroup harbor the biotype-specific cholera-toxin encoding phage (CTX) $CTX^{cla}$, and the El Tor biotype strains contain CTX-1. Although the classical biotype strains have become extinct, a remnant of classical CTX phage is transferred to the El Tor biotype strains. The prototype El Tor strains, which produce the biotype-specific cholera toxin, are now being replaced by atypical El Tor variant strains producing classical biotype cholera toxin. The genome sequences of the CTX phages in atypical El Tor strains indicate that the CTX phages in atypical El Tor strains are a mosaic of $CTX^{cla}$ and CTX-1. Before the emergence of atypical El Tor stains in the early 1990s, unusual pre-seventh pandemic strains were isolated in the US Gulf Coast between 1973 and 1986. These strains have characteristics of atypical El Tor strains since they are El Tor biotype strains containing $CTX^{cla}$, yet the genome sequence of this CTX phage indicates that it is different from $CTX^{cla}$ and is therefore classified separately as $CTX^{US\;Gulf}$.

자연치와 도재관에 대한 색조선택의 동일성 (Shade Matching Identification of in Vivo Natural Teeth and Porcelain-Fused-to-Metal Crowns)

  • 조홍규
    • 대한치과기공학회지
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    • 제29권1호
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    • pp.35-48
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    • 2007
  • The purpose of this study was to evaluate shade selection using conventional visual assessment in vivo natural teeth and porcelain-fused-to-metal (PFM) crown. Maxillary central incisors, lateral incisors and canines of one hundred twenty four college women were used as vivo natural teeth. Fifty one PFM crown for maxillary central incisor fabricated by dental laboratory were used as experimental materials. Using Vitapan Classical Shade Guides, shade selection of natural teeth was measured by each college woman and shade selection of PFM crown was measured by three ceramists with more than ten years career. Both natural teeth and PFM crown shade selection were measured through Shade Eye-Ex. From the shade selection comparing, following results were obtained. The results were as follows: 1. The shade matching identification of natural teeth between the shade selection using Vitapan Classical Shade Guides and the shade selection using Shade Eye-Ex was 27.4% in maxillary central incisor, 13.7% in lateral incisor and 18.5% in canine. 2. Among the shade selection of PFM crown by three ceramists, the shade evaluation of three ceramists were same only in ten cases. In twenty case, those of two ceramists were same. 3. The shade matching identification of PFM crown between the shade selection using Vitapan Classical Shade Guides and the shade selection using Shade Eye-Ex was 38.6% in average. These results suggest that the shade selection using conventional visual assessment should be dealt with care in clinic and need a credible method for shade matching color.

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On the size-dependent behavior of functionally graded micro-beams with porosities

  • Amar, Lemya Hanifi Hachemi;Kaci, Abdelhakim;Tounsi, Abdelouahed
    • Structural Engineering and Mechanics
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    • 제64권5호
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    • pp.527-541
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    • 2017
  • In this work, a new hyperbolic shear deformation beam theory is proposed based on a modified couple stress theory (MCST) to investigate the bending and free vibration responses of functionally graded (FG) micro beam made of porous material. This non-classical micro-beam model introduces the material length scale coefficient which can capture the size influence. The non-classical beam model reduces to the classical beam model when the material length scale coefficient is set to zero. The mechanical material properties of the FG micro-beam are assumed to vary in the thickness direction and are estimated through the classical rule of mixture which is modified to approximate the porous material properties with even and uneven distributions of porosities phases. Effects of several important parameters such as power-law exponents, porosity distributions, porosity volume fractions, the material length scale parameter and slenderness ratios on bending and dynamic responses of FG micro-beams are investigated and discussed in detail. It is concluded that these effects play significant role in the mechanical behavior of porous FG micro-beams.

픽춰레스크와 풍경식 정원 (An Essay on the Picturesque and the Landscape Garden)

  • 김진희;조정송
    • 한국조경학회지
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    • 제24권2호
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    • pp.117-133
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    • 1996
  • The etymological meaning of 'the Picturesque' is "after the manner of painters." It had begun to be used from the end of Classical era and become popular in Romantic era. The concept of the Picturesque in the Classical era is an allusion to the Classical paintings, history paintings or ideal landscapes. As the idea of these paintings was the Beautiful Nature, the most crucial of the Classical Picturesque were that a painting should represent some significant human action; that all the parts of this painting should contribute to the whole; that verbal commentaries were needed. The influence of the Picturesque on the garden design can be summarized as the invention of 'the Landscape Garden.' In the Landscape Garden, human action was central and formal and painterly techiniques were used to highlight human action. The subjectivization of concept of of the beauty resulted in the cult of the Picturesque. In the controversy by Price and Knight, the Picturesque and its influence on the garden design was contended variously. Price criticized the monotonous gardens of Brown's and named "roughness, sudden varitation and irregularity" as the three hallmarks of the Picturesque. Knight contended " that the Picturesque consisted only in a manner of viewing things with an eye and mind educated in the principles of painting" and "that gardens should reproduce as fully as possible the qualities that made the pictures of Rosa or Hobbema delightful."

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Improved Kalman filter with unknown inputs based on data fusion of partial acceleration and displacement measurements

  • Liu, Lijun;Zhu, Jiajia;Su, Ying;Lei, Ying
    • Smart Structures and Systems
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    • 제17권6호
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    • pp.903-915
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    • 2016
  • The classical Kalman filter (KF) provides a practical and efficient state estimation approach for structural identification and vibration control. However, the classical KF approach is applicable only when external inputs are assumed known. Over the years, some approaches based on Kalman filter with unknown inputs (KF-UI) have been presented. However, these approaches based solely on acceleration measurements are inherently unstable which leads poor tracking and so-called drifts in the estimated unknown inputs and structural displacement in the presence of measurement noises. Either on-line regularization schemes or post signal processing is required to treat the drifts in the identification results, which prohibits the real-time identification of joint structural state and unknown inputs. In this paper, it is aimed to extend the classical KF approach to circumvent the above limitation for real time joint estimation of structural states and the unknown inputs. Based on the scheme of the classical KF, analytical recursive solutions of an improved Kalman filter with unknown excitations (KF-UI) are derived and presented. Moreover, data fusion of partially measured displacement and acceleration responses is used to prevent in real time the so-called drifts in the estimated structural state vector and unknown external inputs. The effectiveness and performance of the proposed approach are demonstrated by some numerical examples.