• Title/Summary/Keyword: vector fields

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Named Entity Recognition with Structural SVMs and Pegasos algorithm (Structural SVMs 및 Pegasos 알고리즘을 이용한 한국어 개체명 인식)

  • Lee, Changki;Jang, Myungil
    • Annual Conference on Human and Language Technology
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    • 2010.10a
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    • pp.100-104
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    • 2010
  • 개체명 인식은 정보 추출의 한 단계로서 정보검색 분야 뿐 아니라 질의응답과 요약 분야에서 매우 유용하게 사용되고 있다. 본 논문에서는 structural Support Vector Machines(structural SVMs) 및 수정된 Pegasos 알고리즘을 이용한 한국어 개체명 인식 시스템에 대하여 기술하고 기존의 Conditional Random Fields(CRFs)를 이용한 시스템과의 성능을 비교한다. 실험결과 structural SVMs과 수정된 Pegasos 알고리즘이 기존의 CRFs 보다 높은 성능을 보였고(신뢰도 99%에서 통계적으로 유의함), structural SVMs과 수정된 Pegasos 알고리즘의 성능은 큰 차이가 없음(통계적으로 유의하지 않음)을 알 수 있었다. 특히 본 논문에서 제안하는 수정된 Pegasos 알고리즘을 이용한 경우 CRFs를 이용한 시스템보다 높은 성능 (TV 도메인 F1=85.43, 스포츠 도메인 F1=86.79)을 유지하면서 학습 시간은 4%로 줄일 수 있었다.

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Analysis of Airflows in a Room with Panoramic PIV (파노라마-PIV를 이용한 실내기류 해석)

  • Hwang Tae-Gyu;Doh Deog-Hee
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.17 no.12
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    • pp.1154-1160
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    • 2005
  • A panoramic-PIV system has been constructed for the analysis of the airflows in a room. Smoke is used as seeding particles and are visualized by a pulsed laser (Nd-Yag, 120 mJ). Panoramic images have been obtained by an image composition process using the two images obtained by the two cameras $(1k\times1k)$ that are viewing the wide measurement areas. Velocity vector fields have been obtained by the grey-level cross-correlation PIV method. Three room models $(L{\times}W{\times}H[mm^3],\;500\times500\times250,\;350\times350\times175,\;250\times250\times125)$ have been tested. The experimental results have proven that the constructed panoramic-PIV system can be used as a useful tool for analyzing the airflow characteristics in the room models.

Political Opinion Mining from Article Comments using Deep Learning

  • Sung, Dae-Kyung;Jeong, Young-Seob
    • Journal of the Korea Society of Computer and Information
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    • v.23 no.1
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    • pp.9-15
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    • 2018
  • Policy polls, which investigate the degree of support that the policy has for policy implementation, play an important role in making decisions. As the number of Internet users increases, the public is actively commenting on their policy news stories. Current policy polls tend to rely heavily on phone and offline surveys. Collecting and analyzing policy articles is useful in policy surveys. In this study, we propose a method of analyzing comments using deep learning technology showing outstanding performance in various fields. In particular, we designed various models based on the recurrent neural network (RNN) which is suitable for sequential data and compared the performance with the support vector machine (SVM), which is a traditional machine learning model. For all test sets, the SVM model show an accuracy of 0.73 and the RNN model have an accuracy of 0.83.

LOXODROMES AND TRANSFORMATIONS IN PSEUDO-HERMITIAN GEOMETRY

  • Lee, Ji-Eun
    • Communications of the Korean Mathematical Society
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    • v.36 no.4
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    • pp.817-827
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    • 2021
  • In this paper, we prove that a diffeomorphism f on a normal almost contact 3-manifold M is a CRL-transformation if and only if M is an α-Sasakian manifold. Moreover, we show that a CR-loxodrome in an α-Sasakian 3-manifold is a pseudo-Hermitian magnetic curve with a strength $q={\tilde{r}}{\eta}({\gamma}^{\prime})=(r+{\alpha}-t){\eta}({\gamma}^{\prime})$ for constant 𝜂(𝛄'). A non-geodesic CR-loxodrome is a non-Legendre slant helix. Next, we prove that let M be an α-Sasakian 3-manifold such that (∇YS)X = 0 for vector fields Y to be orthogonal to ξ, then the Ricci tensor 𝜌 satisfies 𝜌 = 2α2g. Moreover, using the CRL-transformation $\tilde{\nabla}^t$ we fine the pseudo-Hermitian curvature $\tilde{R}$, the pseudo-Ricci tensor $\tilde{\rho}$ and the torsion tensor field $\tilde{T}^t(\tilde{S}X,Y)$.

A Study on Face Recognition and Reliability Improvement Using Classification Analysis Technique

  • Kim, Seung-Jae
    • International journal of advanced smart convergence
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    • v.9 no.4
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    • pp.192-197
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    • 2020
  • In this study, we try to find ways to recognize face recognition more stably and to improve the effectiveness and reliability of face recognition. In order to improve the face recognition rate, a lot of data must be used, but that does not necessarily mean that the recognition rate is improved. Another criterion for improving the recognition rate can be seen that the top/bottom of the recognition rate is determined depending on how accurately or precisely the degree of classification of the data to be used is made. There are various methods for classification analysis, but in this study, classification analysis is performed using a support vector machine (SVM). In this study, feature information is extracted using a normalized image with rotation information, and then projected onto the eigenspace to investigate the relationship between the feature values through the classification analysis of SVM. Verification through classification analysis can improve the effectiveness and reliability of various recognition fields such as object recognition as well as face recognition, and will be of great help in improving recognition rates.

A NEW MODELLING OF TIMELIKE Q-HELICES

  • Yasin Unluturk ;Cumali Ekici;Dogan Unal
    • Honam Mathematical Journal
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    • v.45 no.2
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    • pp.231-247
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    • 2023
  • In this study, we mean that timelike q-helices are curves whose q-frame fields make a constant angle with a non-zero fixed axis. We present the necessary and sufficient conditions for timelike curves via the q-frame to be q-helices in Lorentz-Minkowski 3-space. Then we find some results of the relations between q-helices and Darboux q-helices. Furthermore, we portray Darboux q-helices as special curves whose Darboux vector makes a constant angle with a non-zero fixed axis by choosing the curve as one of the types of q-helices, and also the general case.

Stability Analysis of the Magnetic Structures Producing an M6.5 Flare in active region 12371

  • Kang, Jihye;Inoue, Satoshi;Kusano, Kanya;Park, Sung-Hong;Moon, Yong-Jae
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.41.1-41.1
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    • 2019
  • The stability analysis of coronal magnetic structures is important for studying the initiation of solar flares and eruptions. In order to understand the flare onset process, we first reconstructed the 3D coronal magnetic structures of active region 12371 with an M6.5 flare using a nonlinear force-free field (NLFFF) model based on vector magnetic fields. The NLFFFs successfully produce the observed sigmoidal structure which is composed of two branches of sheared arcade loops. The stability analysis were examined for three representative MHD instabilities: the kink, the torus, and the double arc instabilities. Our stability analysis shows that the two branches of sheared arcade loops are quite stable against the kink and torus instabilities, but unstable against the double arc instability before the flare occurrence. Finally, we discuss a probable onset process of the M6.5 flare.

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3-Component Velocity of Magnetized plasma at Solar Photosphere

  • Jung, Hyewon;Moon, Yong-Jae
    • The Bulletin of The Korean Astronomical Society
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    • v.44 no.2
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    • pp.70.3-70.3
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    • 2019
  • We present a method to estimate 3-component plasma velocity (Vx, Vy and Vz) at solar photosphere near solar disk center, using the Helioseismic and Magnetic Imager (HMI) onboard the Solar Dynamics Observatory (SDO) called Space-weather HMI Active Region Patch (SHARP). In Heliocentric-Cartesian Coordinates, the component of Vz is obtained from Dopplergram while the components of Vx and Vy are derived from the relation of $B_z{\overrightarrow{u}}=B_z{\overrightarrow{{\nu}_t}}-{\nu}_z{\overrightarrow{B_t}}$ (Demoulin & Berger 2003) using a series of vector magnetograms by an optical flow technique NAVE (Nonlinear Affine Velocity Estimator). This velocity measurement method is applied to AR 12158 producing an X1.6 flare along with a coronal mass ejection. We find noticeable upflow motions at both ends of flux ropes which become a major eruption part, and strong transverse motions nearby them before the eruption. We will discuss the change of plasma motions and magnetic fields before and after the eruption.

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SEMI-SYMMETRIC STRUCTURE JACOBI OPERATOR FOR REAL HYPERSURFACES IN THE COMPLEX QUADRIC

  • Imsoon Jeong;Gyu Jong Kim;Changhwa Woo
    • Bulletin of the Korean Mathematical Society
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    • v.60 no.4
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    • pp.849-861
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    • 2023
  • In this paper, we introduce the notion of semi-symmetric structure Jacobi operator for Hopf real hypersufaces in the complex quadric Qm = SOm+2/SOmSO2. Next we prove that there does not exist any Hopf real hypersurface in the complex quadric Qm = SOm+2/SOmSO2 with semi-symmetric structure Jacobi operator. As a corollary, we also get a non-existence property of Hopf real hypersurfaces in the complex quadric Qm with either symmetric (parallel), or recurrent structure Jacobi operator.

Theater Reservation System Using SVG(Scalable Vector Graphics) (SVG(Scalable Vector Graphics)를 활용한 극장 예약 시스템)

  • Jeon, Tae-Ryong;An, Seong-Ok
    • The Journal of Engineering Research
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    • v.5 no.1
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    • pp.17-35
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    • 2004
  • Svg(Scalable Vector Graphics) is xml graphic standard recommended by E3C as a language based on xml to express two-dimension graphic. Svg can accommodate all Xml's patency and advantage of interoperability, and can used as various web applications being combined with other xml language. In addition, Svg can be applied to the fields of electronic commerce, geographical information, computer education and advertisement because it can produce high quality of dynamic from real-time data. SVG's application can be enhanced by linking with database. In this paper, we discuss how Svg can be utilized in theater reservation system, not just explaining svg's meaning or ability. Svg added graphic advantage in addition to xml's advantage. This means that svg retains not only graphic element but also xml's softness. It becomes easier to designate seats and add them. Current reservation system provided in general only information on time and price for a ticket, but the system using SVG in this paper provides additional information on position, price, cancellation and purchase availability of seat.

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