• 제목/요약/키워드: Pseudo

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Note on Almost Generalized Pseudo-Ricci Symmetric Manifolds

  • Baishya, Kanak Kanti
    • Kyungpook Mathematical Journal
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    • 제57권3호
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    • pp.517-523
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    • 2017
  • The purpose of the present paper is to study an almost generalized pseudo-Ricci symmetric manifold. The existence of such manifold is ensured by an example. Furthermore, having found, faulty example in [13], the present paper also attempts to construct a non-trivial example of an almost pseudo Ricci symmetric manifold.

79종의 임플란트 식별을 위한 딥러닝 알고리즘 (Deep learning algorithms for identifying 79 dental implant types)

  • 공현준;유진용;엄상호;이준혁
    • 구강회복응용과학지
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    • 제38권4호
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    • pp.196-203
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    • 2022
  • 목적: 본 연구는 79종의 치과 임플란트에 대해 딥러닝을 이용한 식별 모델의 정확도와 임상적 유용성을 평가하는 것을 목적으로 하였다. 연구 재료 및 방법: 2001년부터 2020년까지 30개 치과에서 임플란트 치료를 받은 환자들의 파노라마 방사선 사진에서 총 45396개의 임플란트 고정체 이미지를 수집했다. 수집된 임플란트 이미지는 18개 제조사의 79개 유형이었다. 모델 학습을 위해 EfficientNet 및 Meta Pseudo Labels 알고리즘이 사용되었다. EfficientNet은 EfficientNet-B0 및 EfficientNet-B4가 하위 모델로 사용되었으며, Meta Pseudo Labels는 확장 계수에 따라 두 가지 모델을 적용했다. EfficientNet에 대해 Top 1 정확도를 측정하고 Meta Pseudo Labels에 대해 Top 1 및 Top 5 정확도를 측정하였다. 결과: EfficientNet-B0 및 EfficientNet-B4는 89.4의 Top 1 정확도를 보였다. Meta Pseudo Labels 1은 87.96의 Top 1 정확도를 보였고, 확장 계수가 증가한 Meta Pseudo Labels 2는 88.35를 나타냈다. Top 5 정확도에서 Meta Pseudo Labels 1의 점수는 97.90으로 Meta Pseudo Labels 2의 97.79보다 0.11% 높았다. 결론: 본 연구에서 임플란트 식별에 사용된 4가지 딥러닝 알고리즘은 모두 90%에 가까운 정확도를 보였다. 임플란트 식별을 위한 딥러닝의 임상적 적용 가능성을 높이려면 더 많은 데이터를 수집하고 임플란트에 적합한 미세 조정 알고리즘의 개발이 필요하다.

LES를 이용한 Pseudo-Shock Waves의 가시화 (Numerical Visualization of the Pseudo-Shock Waves using LES)

  • ;;김희동
    • 한국가시화정보학회지
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    • 제13권3호
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    • pp.29-34
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    • 2015
  • The interaction between a normal shock wave and a boundary layer along a wall surface in internal compressible flows causes a very complicated flow. This interaction region containing shock train and mixing region is called as pseudo-shock waves. Pseudo-shock waves in the divergent part of a rectangular nozzle have been investigated by using large-eddy simulation (LES). LES studies have been done for the complex flow phenomena of three-dimensional pseudo-shock waves. The LES results have been validated against experimental wall-pressure measurements. The LES results are in good agreement with experimental results. Pseudo-shock length and corner separation have been studied in three-dimensional LES model. Comparison of centerline pressure measurement and 3D visualization measurement has been discussed for the corner separation position. It has been concluded that the pseudo-shock length should be measured by using 3D visualization measurement.

고전압 대전류 Multichannel Pseudo-spark 스위치 연구 (Study of Multichannel Pseudo-spark Switch for High-voltage and High-current)

  • 박성수;한영진;김상희;권영건;김승환;박용정;남상훈
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2002년도 하계학술대회 논문집 C
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    • pp.1859-1861
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    • 2002
  • This paper attempts to discuss the pseudo-spark which is developed for high voltage and high current. The pseudo-spark switch is on the basic of the Paschen's law. The pseudo-spark switch fabricates the glass chamber. The pseudo-spark switch consists of hollow cathode, hollow anode, and trigger. The pseudo-spark switch is operated at the voltage of 20 kV and the pressure range of $20{\sim}80$ mtorr with He-gas. The switching current of the pseudo-spark switch was measured as 65 kA, and the duration of the pulse was about 100 ${\mu}s$. This paper describes the results of tests and the characteristics of the switch.

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Inhibition of Lipopolysaccharide-Induced Expression of Inducible Nitric Oxide and Cyclooxygenase-2 by Aquaous of Aconitum pseudo-laeve var. erectum in RAW 264.7 Macrophages

  • Han, Myung-Soo;Lee, Jae-Hyok;Kim, Ee-Hwa
    • 동의생리병리학회지
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    • 제22권3호
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    • pp.678-683
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    • 2008
  • Aconitum pseudo-laeve var. erectum has traditionally been used for the treatment of water retention in the body. Administration of the aqueous extract of Aconitum pseudo-laeve var. erectum has the efficiency of anti-inflammatory activity and modulates the intestinal immune system. However, the mechanism of anti-inflammatory action of Aconitum pseudo-laeve var. erectum has not been clarified yet. In the present study, the effect of Aconitum pseudo-laeve var. erectum against LPS-stimulated expressions of COX-2 and iNOS in cells of the murine RAW 264.7 macrophages was investigated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, reverse transcription- polymerase chain reaction (RT-PCR), PGE2 immunoassay, and NO detection. The results of the present study indicate that Aconitum pseudo-laeve var. erectum is a potent inhibitor of the LPS-induced NO and $PGE_{2}$ production by blocking iNOS and $NF{\kappa}B$ activation in RAW 264.7 macrophages. These findings suggest that Aconitum pseudo-laeve var. erectum is a potential therapeutic for the treatment of inflammatory syndrome.

Seismic stability analysis of tunnel face in purely cohesive soil by a pseudo-dynamic approach

  • Huang, Qi;Zou, Jin-feng;Qian, Ze-hang
    • Geomechanics and Engineering
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    • 제23권1호
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    • pp.1-13
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    • 2020
  • To give a solution for seismic stability of tunnel faces subjected to earthquake ground shakings, the pseudo-dynamic approach is originally introduced to analyze tunnel face stability in this study. In the light of the upper-bound theorem of limit analysis, an advanced three-dimensional mechanism combined with pseudo-dynamic approach is proposed. Based on this mechanism, the required support pressure on tunnel face can be obtained by equaling external work rates to the internal energy dissipation and implementing an optimization searching procedure related to time. Both time and space feature of seismic waves are properly accounted for in the proposed mechanism. For this reason, the proposed mechanism can better represent the actual influence of seismic motion and has a remarkable advantage in evaluating the effects of vertical seismic acceleration, soil amplification factor, seismic wave period and initial phase difference on tunnel face stability. Furthermore, the pseudo-dynamic approach is compared with the pseudo-static approach. The difference between them is illustrated from a new but understandable perspective. The comparison demonstrates that the pseudo-static approach is a conservative method but still could provide precise enough results as the pseudo-dynamic approach if the value of seismic wavelengths is large or the height of soil structures is small.

Estimation of Ionospheric Delays in Dual Frequency Positioning - Future Possibility of Using Pseudo Range Measurements -

  • Isshiki, Hiroshi
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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    • pp.185-190
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    • 2006
  • The correct estimation of the ionospheric delays is very important for the precise kinematic positioning especially in case of the long baseline. In case of triple frequency system, the ionospheric delays can be estimated from the measurements, but, in case of dual frequency system, the situation is not so simple. The precision of those supplied by the external information source such as IONEX is not sufficient. The high frequency component is neglected, and the precision of the low frequency component is not sufficient for the long baseline positioning. On the other hand, the high frequency component can be estimated from the phase range measurements. If the low frequency components are estimated by using the external information source or pseudo range measurements, a more reasonable estimation of the ionospheric delays may be possible. It has already been discussed by the author that the estimation of the low frequency components by using the external information source is not sufficient but fairly effective. The estimation using the pseudo range measurements is discussed in the present paper. The accuracy is not sufficient at present because of the errors in the pseudo range measurements. It is clarified that the bias errors in the pseudo range measurements are responsible for the poor accuracy of the ionospheric delays. However, if the accuracy of the pseudo range measurements is improved in future, the method would become very promising.

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유사학생발화의 유형과 분류 (Patterns and Usage of Pseudo Student Talk (PST))

  • 신윤주;최승언
    • 한국지구과학회지
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    • 제29권1호
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    • pp.78-90
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    • 2008
  • 수업 중 발화의 대부분을 차지하는 것은 교사의 발화이다. 그러나 교사는 항상 교사의 입장에서만 말하는 것이 아니라 학생 발화와 유사한 발화를 통해 학생들의 수업에 도움을 줄 수 있을 것으로 생각되나 이에 대한 연구는 아직 부족한 것이 현실이다. 따라서 본 논문에서는 이러한 발화 형태를 유사학생발화라 명명하고, 유사학생발화가 다수 관찰될 것으로 예상되는 방송 수업(EBS의 2005학년도 중 1 과학 수업 중 지구과학 부분)을 연구하여 유사학생발화를 '수업 중, 학생 발화와 같은 역할을 하나, 교사를 통해 이루어지는 모든 발화의 통칭'이라 정의하였으며, Lemke(1990)의 학생발화분류를 토대로 연구 대상인 수업 중 나타난 유사학생발화를 교사가 개입하는 형태의 유사학생발화와 교사가 개입하지 않는 유사학생발화로 크게 유사학생발화를 나누고 교사 개입 유사학생발화로 유사 교사-학생 간 협의(Pseudo Teacher-Student Conferences), 유사 삼단계 담화(Pseudo Triadic Dialogue), 유사 교재 활용 담화(Pseudo External Text Dialogue), 유사 학생 질문 담화(Pseudo Student-Questioning Dialogue), 유사 교사-학생 간 담화(Pseudo Teacher-Student Dialogue), 유사 교사-학생 간 토론(Pseudo Teacher-Student Debate), 유사 실 담화(Pseudo True Dialogue), 유사 학생 상호 담화(Pseudo Cross Dialogue), 유사 동료 학생 발화 (Pseudo classmate talk)를, 그리고 교사 미개입 유사학생발화로 유사 학생 독백/유사 수업 중 잡담(Pseudo student monologue/Pseudo side talk)을 분류하였다. 또한 이러한 분류와 함께 각 유사학생발화의 실례를 소개하고 그 특징을 기술하였다.