• Title/Summary/Keyword: recurrent space

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THE INDUCED AND INTRINSIC CONNECTIONS OF BERWALD TYPE IN A FINSLERIAN HYPERSURFACE

  • Ha Yong Park;Hong Suh Park
    • Communications of the Korean Mathematical Society
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    • v.12 no.2
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    • pp.383-391
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    • 1997
  • The main purpose of the present paper is to derive the induced (Finsler) connections on the hypersurface from the Finsler connections of Berwald type (a Berwald h-recurrent connection and a $F\Gamma$' connection) of a Finsler space and to seek the necessary and sufficient conditions that the induced connections coincide with the intrinsic connections. And we show the quantities and relations with respect to the respective induced connections. Finally we show some examples.

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ON THE "TERRA INCOGNITA" FOR THE NEWTON-KANTROVICH METHOD WITH APPLICATIONS

  • Argyros, Ioannis Konstantinos;Cho, Yeol Je;George, Santhosh
    • Journal of the Korean Mathematical Society
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    • v.51 no.2
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    • pp.251-266
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    • 2014
  • In this paper, we use Newton's method to approximate a locally unique solution of an equation in Banach spaces and introduce recurrent functions to provide a weaker semilocal convergence analysis for Newton's method than before [1]-[13], in some interesting cases, provided that the Fr$\acute{e}$chet-derivative of the operator involved is p-H$\ddot{o}$lder continuous (p${\in}$(0, 1]). Numerical examples involving two boundary value problems are also provided.

Design of Torque Compensatory Controller for Robot Manipulator using Chaotic Neural Networks (카오틱 신경망을 이용한 로봇 매니퓰레이터용 토크보상제어기의 설계)

  • Moon, Chan;Kim, Sang-Hee;Park, Won-Woo
    • Proceedings of the KIEE Conference
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    • 1998.11b
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    • pp.530-532
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    • 1998
  • In this paper, We Designed the torque compensatory controller for robot manipulator using modified chaotic neural networks with self feedback loop. The proposed torque compensatory controller compensate torque of the PD controller. In order to estimate the proposed controller, we implemented to the Cartesian space control of three-axis PUMA robot and compared the simulation results with recurrent neural networks(RNNs) controller. Simulation results show that the learning error drastically decrease at on-line learning. The proposed CNNs controller shows much better control performance and shorter processing time compared to the recurrent neural network controller in the robot trajectory control.

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AVERAGE SHADOWING PROPERTIES ON COMPACT METRIC SPACES

  • Park Jong-Jin;Zhang Yong
    • Communications of the Korean Mathematical Society
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    • v.21 no.2
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    • pp.355-361
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    • 2006
  • We prove that if a continuous surjective map f on a compact metric space X has the average shadowing property, then every point x is chain recurrent. We also show that if a homeomorphism f has more than two fixed points on $S^1$, then f does not satisfy the average shadowing property. Moreover, we construct a homeomorphism on a circle which satisfies the shadowing property but not the average shadowing property. This shows that the converse of the theorem 1.1 in [6] is not true.

THE STRUCTURE OF ALMOST REGULAR SEMIGROUPS

  • Chae, Younki;Lim, Yongdo
    • Bulletin of the Korean Mathematical Society
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    • v.31 no.2
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    • pp.187-192
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    • 1994
  • The author extended the small properties of topological semilattices to that of regular semigroups [3]. In this paper, it could be shown that a semigroup S is almost regular if and only if over bar RL = over bar R.cap.L for every right ideal R and every left ideal L of S. Moreover, it has shown that the Bohr compactification of an almost regular semigroup is regular. Throughout, a semigroup will mean a topological semigroup which is a Hausdorff space together with a continuous associative multiplication. For a semigroup S, we denote E(S) by the set of all idempotents of S. An element x of a semigroup S is called regular if and only if x .mem. xSx. A semigroup S is termed regular if every element of S is regular. If x .mem. S is regular, then there exists an element y .mem S such that x xyx and y = yxy (y is called an inverse of x) If y is an inverse of x, then xy and yx are both idempotents but are not always equal. A semigroup S is termed recurrent( or almost pointwise periodic) at x .mem. S if and only if for any open set U about x, there is an integer p > 1 such that x$^{p}$ .mem.U.S is said to be recurrent (or almost periodic) if and only if S is recurrent at every x .mem. S. It is known that if x .mem. S is recurrent and .GAMMA.(x)=over bar {x,x$^{2}$,..,} is compact, then .GAMMA.(x) is a subgroup of S and hence x is a regular element of S.

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A Tensor Space Model based Deep Neural Network for Automated Text Classification (자동문서분류를 위한 텐서공간모델 기반 심층 신경망)

  • Lim, Pu-reum;Kim, Han-joon
    • Database Research
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    • v.34 no.3
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    • pp.3-13
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    • 2018
  • Text classification is one of the text mining technologies that classifies a given textual document into its appropriate categories and is used in various fields such as spam email detection, news classification, question answering, emotional analysis, and chat bot. In general, the text classification system utilizes machine learning algorithms, and among a number of algorithms, naïve Bayes and support vector machine, which are suitable for text data, are known to have reasonable performance. Recently, with the development of deep learning technology, several researches on applying deep neural networks such as recurrent neural networks (RNN) and convolutional neural networks (CNN) have been introduced to improve the performance of text classification system. However, the current text classification techniques have not yet reached the perfect level of text classification. This paper focuses on the fact that the text data is expressed as a vector only with the word dimensions, which impairs the semantic information inherent in the text, and proposes a neural network architecture based upon the semantic tensor space model.

Study on Q-value prediction ahead of tunnel excavation face using recurrent neural network (순환인공신경망을 활용한 터널굴착면 전방 Q값 예측에 관한 연구)

  • Hong, Chang-Ho;Kim, Jin;Ryu, Hee-Hwan;Cho, Gye-Chun
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.22 no.3
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    • pp.239-248
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    • 2020
  • Exact rock classification helps suitable support patterns to be installed. Face mapping is usually conducted to classify the rock mass using RMR (Rock Mass Ration) or Q values. There have been several attempts to predict the grade of rock mass using mechanical data of jumbo drills or probe drills and photographs of excavation surfaces by using deep learning. However, they took long time, or had a limitation that it is impossible to grasp the rock grade in ahead of the tunnel surface. In this study, a method to predict the Q value ahead of excavation surface is developed using recurrent neural network (RNN) technique and it is compared with the Q values from face mapping for verification. Among Q values from over 4,600 tunnel faces, 70% of data was used for learning, and the rests were used for verification. Repeated learnings were performed in different number of learning and number of previous excavation surfaces utilized for learning. The coincidence between the predicted and actual Q values was compared with the root mean square error (RMSE). RMSE value from 600 times repeated learning with 2 prior excavation faces gives a lowest values. The results from this study can vary with the input data sets, the results can help to understand how the past ground conditions affect the future ground conditions and to predict the Q value ahead of the tunnel excavation face.

Diagnostic and management challenge of concurrent tongue squamous cell carcinoma with an unknown parapharyngeal mass

  • Raymond Shupak;Roderick Kim;Jun Hyuk Huh
    • Journal of the Korean Association of Oral and Maxillofacial Surgeons
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    • v.50 no.1
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    • pp.56-59
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    • 2024
  • There are very few case reports of the diagnosis and management of concurrent oral cavity and parapharyngeal space tumors. We present a case involving a 49-year-old female who presented with oral cavity squamous cell carcinoma confirmed by biopsy. Initial diagnostic workup revealed a concurrent parapharyngeal mass. Diagnostic studies and surgical therapy were tailored to account for both pathological entities. The patient was treated with a combination of surgery and adjuvant therapy. The surgical strategy was designed to address both lesions simultaneously. One year post-surgery, the patient had good response to therapy with no evidence of persistent or recurrent disease. This report discusses the outcome and treatment of a rare case of concurrent squamous cell carcinoma with a complicating parapharyngeal space tumor. It explores the diagnostic process, comprehensive workup, and the surgical management.

NONWANDERING POINTS OF A MAP ON THE CIRCLE

  • Bae, Jong-Sook;Cho, Seong-Hoon;Min, Kyung-Jin;Yang, Seung-Kab
    • Journal of the Korean Mathematical Society
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    • v.33 no.4
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    • pp.1115-1122
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    • 1996
  • In study of the dynamics of a map f from a topological space X to itself, a central role is played by the various recursive properties of the points of X. One such property is periodicity. A weaker property is that of being nonwandering. Intermediate recursive properties include almost periodicity and recurrence.

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CHARACTERIZATIONS ON CHAIN RECURRENCES

  • Park, Jong-Suh;Ku, Se-Hyun
    • Bulletin of the Korean Mathematical Society
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    • v.47 no.2
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    • pp.287-293
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    • 2010
  • It is well known that there is a residual subset J of the space of $C^1$-diffeomorphisms on a compact Riemannian manifold M such that the maps f $\mapsto$ chain recurrent set of f and f $\mapsto$ number of chain components of f are continuous on J. In this paper we get the flow version of the above results on diffeomorphisms.