ON SPECTRAL BOUNDEDNESS

Harte, Robin Korean Mathematical Society 2003 대한수학회지 Vol.40 No.2

For linear operators between Banach algebras "spectral boundedness" is derived from ordinary boundedness by substituting spectral radius for norm. The interplay between this concept and some of its near relatives is conspicuous in a result of Curto and Mathieu.

Finite-time H∞ Control for Switched Systems with Time-varying Delay using Delta Operator Approach

Chen Qin,Zhengrong Xiang,Hamid Reza Karimi 제어·로봇·시스템학회 2014 International Journal of Control, Automation, and Vol.12 No.6

Finite-time H∞ control for switched systems with time-varying delay using delta operator approach is investigated in this paper. Firstly, by using the average dwell time approach and delta operator theory, sufficient conditions for H∞ finite-time boundedness of the underlying systems are derived. Then a state feedback controller is proposed such that the resulting closed-loop system is H∞ finite-time bounded. All the obtained results are formulated in terms of linear matrix inequalities (LMIs). Finally, an example is presented to show the validity of the proposed results.

한정성 전치사 IN의 의미 구조

김주식(Ju Shik Kim) 언어과학회 2005 언어과학연구 Vol.32 No.-

In this article I investigate the polysemy of the preposition in. First I provide the study of prepositions by Lindner(1983) as a theoretical background for this article. The problem of the Lindner`s approach is that she uses the concept of movement in presenting image schema for prepositions in and out. The concept of movement involves the relation which evolves over time, so the concept is typically the basic attribute of verbs. On the other hand, prepositions are atemporal. Prepositions refers to the asymmetrical relation of the trajector and the landmark, but not to the movement of the trajector. In this article, I present the image schema of preposition in not using the concept of movement and investigate the relation of the meanings associated with in. And I demonstrate that the meanings associated with in should be approached in terms of polysemy approach, but not in terms of approaches of homonymy and monosemy. There are five semantic clusters in the semantic network of in the location cluster, the interior vantage-point cluster, the exterior vantage-point cluster, the segmentation cluster, reflexivity. From the location cluster arise a range of closely related meanings of In Situ Sense, State Sense, Activity Sense, Means Sense. The interior vantage- point cluster gives rise to many distinct meanings of Perceptual Accessibility Sense, In Favour Sense, Arrival Sense. The exterior vantage-point cluster gives rise to the meaning of the Disappearance Sense. The segmentation cluster gives rise to the meanings of The Shape As Boundary Sense and Blockage Sense. And reflexivity gives rise to Reflexive Sense. Finally, I study the contrast of in and into. English preposition in is not related to orientation but to the bounded landmark, while preposition into is related to orientation. Later I will study the relatedness of in and out which are in the same category of prepositions which use the concept of boundedness.

An Adaptive Tracking Control for Robotic Manipulators based on RBFN

Min-Jung Lee,Tae-Seok Jin 한국지능시스템학회 2007 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.7 No.2

Neural networks are known as kinds of intelligent strategies since they have learning capability. There are various their applications from intelligent control fields; however, their applications have limits from the point that the stability of the intelligent control systems is not usually guaranteed. In this paper we propose an adaptive tracking control for robot manipulators using the radial basis function network (RBFN) that is a kind of neural networks. Adaptation laws for parameters of the RBFN are developed based on the Lyapunov stability theory to guarantee the stability of the overall control scheme. Filtered tracking errors between actual outputs and desired outputs are discussed in the sense of the uniformly ultimately boundedness(UUB). Additionally, it is also shown that parameters of the RBFN are bounded. Experimental results for a SCARA-type robot manipulator show that the proposed adaptive tracking controller is adaptable to the environment changes and is more robust than the conventional PID controller and the neuro-controller based on the multilayer perceptron.

An Adaptive Tracking Control for Robotic Manipulators based on RBFN

Lee, Min-Jung,Jin, Tae-Seok Korean Institute of Intelligent Systems 2007 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.7 No.2

Neural networks are known as kinds of intelligent strategies since they have learning capability. There are various their applications from intelligent control fields; however, their applications have limits from the point that the stability of the intelligent control systems is not usually guaranteed. In this paper we propose an adaptive tracking control for robot manipulators using the radial basis function network (RBFN) that is e. kind of neural networks. Adaptation laws for parameters of the RBFN are developed based on the Lyapunov stability theory to guarantee the stability of the overall control scheme. Filtered tracking errors between actual outputs and desired outputs are discussed in the sense of the uniformly ultimately boundedness(UUB). Additionally, it is also shown that parameters of the RBFN are bounded. Experimental results for a SCARA-type robot manipulator show that the proposed adaptive tracking controller is adaptable to the environment changes and is more robust than the conventional PID controller and the neuro-controller based on the multilayer perceptron.

한국어 부사 ‘거의’의 근접성과 양화

김송희(Kim, Songhee) 한국어문학회 2017 語文學 Vol.0 No.136

The purpose of this article is to explore the meaning and function of an adverb ‘geoui’ and its following elements. ‘Geoui’ requires bounded words to be included in the following predicate. Therefore, the predicate following ‘geoui’ usually consists of a bounded adjective or a telic verb, which is semantically bounded. In addition, the adverb ‘geoui’ involves negative references and contextual boundary especially when it is followed by unbounded adjectives or atelic verbs. In these cases, ‘geoui’ is a degree adverb that designates proximity. On the other hand, ‘geoui’ is used with the quantificational expression in a form of noun, adverb, or determiner. In those cases, ‘geoui’ quantifies the case of the sentence and functions as a frequency adverb.

Fixed-time Congestion Tracking Control for a Class of Uncertain TCP/AQM Computer and Communication Networks

Jindong Shen,Yuanwei Jing,Georgi Marko Dimirovski 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.3

The fixed-time congestion control problem of TCP/AQM networks with UDP flows and un-modeled uncertainties has been studied thoroughly in this paper. The fluid-flow based TCP/AQM network system model is analyzed, and a fixed-time adaptive congestion control algorithm is proposed for the nonlinear network system model with unknown UDP flows and un-modeled uncertainty. The new control algorithm was derived using combined requirements for the fixed-time control and the prescribed performance control by employing the backstepping technique and the fuzzy approximation methodology. The universal approximation property of fuzzy-logic system models is used to deal with the external disturbance and the uncertainty that may appear in the network system. Using the prescribed performance technology, the transient and steady state performances of the tracking error are shown to have been enforced to meet the design requirements. Using the back-stepping methodology, a fixedtime AQM controller is designed so as to ensure that the fixed time of the closed-loop system response remains bounded. The obtained simulation results demonstrate the extent of effectiveness and superiority of the proposed design relative to known previous results.

Control of a Chain of Power Integrators with High-order Nonlinearity: A Bi-directional Approach

Sang-Young Oh,최호림 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.1

In this paper, we consider a control problem for a chain of power integrators with perturbed high-order nonlinearity. The main feature distinguishing the system considered in this study from those in prior works is that the high-order nonlinearity is bi-directional, in that it can be in either the lower triangular or upper triangular forms. To deal with such a system, we propose an unified switching controller wherein one of two dynamic gains is chosen depending on the form of nonlinearity. Our new control approach is to utilize dual adaptive gains where one gain is to suppress high-order nonlinearity and the other gain is to derive the system states into (small) bounds. With our control scheme, all states of the controlled systems are shown to be bounded. Moreover, a discussion is provided to demonstrate a way to achieve smaller bounds through the selection of control parameters. The effectiveness of our control scheme is illustrated via numerical examples.

합성동사 구성의 한계성 실현 양상

홍윤기 형태론 2006 형태론 Vol.8 No.1

Based on the assumption that the aspectual meaning suggested by a complex verb construction can differ from the meanings of its individual constituent verb constructions, this study compared the situation types of complex verb constructions and singular verb constructions. In addition, it tried to examine the boundedness of the construction situations profiled. Through this examination, we found that when the preceding verb and following verb take the same theme argument as object, the theme argument obtains the boundedness of theme by matching with an aspectual role and the boundedness decides the boundedness of the complex verb construction. But when each preceding verb and following verb takes its theme argument as an object and takes its goal argument as an obligatory adverb phrase, the theme argument cannot match with a particular aspect role and the boundedness disappears. The goal argument matches with terminus and obtains boundedness along with an undetermined path. The boundedness of space decides the boundedness of the complex verb construction. We need to inspect closely the meaningful characteristics ka- “go” used as a following and preceding verb in complex verbs. Through an examination of the relation between a preceding and a following ka- “go” in meaning, we can elucidate the characteristics related with the aspectual meaning of complex verb constructions including ka- “go”. By examining which aspectual roles match with the arguments in complex verb constructions, we can understand not only the ways in which boundedness is realized, but also the differences in realization of boundedness between individual verbs and complex verb constructions. 합성동사 구성의 상황이 드러내는 상적 의미를 설명하기 위해서는 각 구성의 상황유형과 그 구성에 실현된 논항들의 상 역할 등을 검토하는 것이 필요하다. 이를 바탕으로 각 구성의 상황이 드러내는 한계성이 활성화되는 양상을 논의할 수 있다. 선․후행동사가 동일한 대상 논항을 목적어로 취하는 경우 그 대상 논항은 상 역할 [잣대]에 대응함으로써 대상의 한계성을 얻게 되고 그 한계성이 합성동사 구성의 한계성을 결정한다. 한편, 선․후행동사가 각각 대상 논항을 목적어로, 도달점 논항을 필수적 부사어로 취할 경우, 대상 논항은 특정한 상 역할에 대응하지 못하고 그 한계성이 소멸되는 반면에 도달점 논항은 [완결점]에 대응하고 암시적 경로와 더불어 한계성을 가진다. 공간의 한계성은 합성동사의 한계성을 결정한다. 합성동사 구성의 논항들이 어떤 상 역할에 대응하는지를 면밀히 검토함으로써 한계성 실현의 방식을 파악할 수 있고 개별동사 구성과 합성동사 구성간의 한계성 실현의 차이를 알 수 있다.

Functional differential equations, uniform asymptotic stability

KO, YOUNHEE 濟州大學校 基礎科學硏究所 1997 基礎科學硏究 Vol.10 No.1

It is well known that for a functional differential equation with unbounded delay which is sufficiently well posed in a certain phase space, existence of a periodic solution follows directly if solutions are uniformly bounded and uniformly ultimately bounded with respect to this phase space. Thus the properties of uniform boundedness and uniform ultimate boundedness frequently emerge as central. The purpose of this section is to develop conditions ensuring such boundedness propertise for solutions of unbounded delay functional differential equations.