• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2007년도 춘계학술대회B
• /
• pp.2444-2448
• /
• 2007

The multi channel of DDI which is the core part of the LCD-TV has been propelled. When multi channel in DDI is introduced, it brings a thermal problem because of the increased power. To solve the thermal problem of the DDI it needs to be investigated each at the package level and module level. It is important to extract the junction temperature(Tj) of DDI clearly from the system level. The objective of this research is to construct a compact model. The compact model is to reduce LCD module including DDI. When the compact model is used, it will be able to easily handle the boundary condition and accurately predict the temperature. Consequently, the temperature of DDI can be calculated easily at the system level. Through this research,we also proposed the cooling plan of DDI for a protection of overheating. The cooling plan was utilized in DDI design.

• 제어로봇시스템학회논문지
• /
• 제10권5호
• /
• pp.385-394
• /
• 2004

This paper proposes the generalized structure of a model-based disturbance rejection controller called a Robust Internal-loop Compensator (RIC). The framework consists of the RIC in the internal-loop to eliminate disturbances and a feedback controller in the external-loop to achieve nominal control performance. As the main contribution of this paper, we redefine the design problem of the RIC as a regulation control problem, then show that this new definition with the RIC structure provides more design flexibility and less implementation constraints. This is verified through a comparative structural analysis with Disturbance Observer (DOB) and Adaptive Robust Control (ARC). Two design examples of the RIC are given, along with practical issues that should be considered in the design procedure. The proposed framework is demonstrated by simulations of a rotary-type motor and experiments with a linear-type motor system.

• 한국CDE학회논문집
• /
• 제17권4호
• /
• pp.282-293
• /
• 2012

This paper presents an error-bounded B-spline fitting technique to approximate unorganized data within a prescribed error tolerance. The proposed approach includes two main steps: leastsquares minimization and error-bounded approximation. A B-spline hypervolume is first described as a data representation model, which includes its mathematical definition and the data structure for implementation. Then we present the least-squares minimization technique for the generation of an approximate B-spline model from the given data set, which provides a unique solution to the problem: overdetermined, underdetermined, or ill-conditioned problem. We also explain an algorithm for the error-bounded approximation which recursively refines the initial base model obtained from the least-squares minimization until the Euclidean distance between the model and the given data is within the given error tolerance. The proposed approach is demonstrated with some examples to show its usefulness and a good possibility for various applications.

• 한국언어정보학회지:언어와정보
• /
• 제8권2호
• /
• pp.1-25
• /
• 2004

This paper examines two different approaches to resolving a theoretical problem which the bottom-up approach version of Discourse Representation Theory of Kamp et al. (2003) faces in dealing with anaphoric relations between pronouns and their potential antecedents in conditional sentences where consequent clauses precede their corresponding conditional clauses. In one of the approaches, every element is processed in the order of occurrence and conditional operators in a non-sentence-initial position cause the ongoing DR to split in two with the same index. The definition of accessibility is accordingly modified so that the right DR can be accessible from the left DR. In the other approach, a different type of discourse representation structure, K ${\Leftarrow}$ K, is introduced, which allows us to resolve the target problem without modifying accessibility proposed in Kamp et al. (2003). Compatibility of these two approaches with the bottom-up version of DRT is evaluated by examining their applicability to the analysis of quantified sentences where pronominal expressions precede generalized quantifiers.

• 전자통신동향분석
• /
• 제33권2호
• /
• pp.39-47
• /
• 2018

The fundamental problem of communication is that of transmitting a message from a source to a destination over a channel through the use of a transmitter and receiver. To derive a theoretically optimal solution, the transmitter and receiver can be divided into several processing blocks, with each component analyzed and optimized. The idea of machine learning (or deep learning) communications systems goes back to the original definition of the communi-cation problem, and optimizes the transmitter and receiver jointly. Although today's systems have been optimized over the last decades, and it seems difficult to compete with their performance, deep learning based communication is attractive owing to its simplicity and the fact that it can learn to communicate over any type of channel without the need for mathematical modeling or analysis.

• 한국수학교육학회지시리즈D:수학교육연구
• /
• 제10권3호
• /
• pp.215-227
• /
• 2006

After reviewing China's appearance and research on the Math open-ended problems, together with the application of those problems in mathematics test of Shanghai Senior Middle School Entrance Exams (SSMSEE) since 1999, this paper points out the difficulty in establishing an evaluation system for such problem. Through comparative study, the paper gives an operational definition of open-ended problem, and it attempts to establish an evaluation system and non-systematic competence targets that are appropriate to Math open-ended problems. Meanwhile, it describes the performance feature of those targets. By applying the standard international grading system of difficulty, it discusses the elements of difficulty in Math open-ended problems, and puts forward an evaluation as well as a level-of-difficulty forecasting system that is appropriate to the Middle School Entrance Exam.

• 한국수학사학회지
• /
• 제15권2호
• /
• pp.49-68
• /
• 2002

One of the characteristics of modem mathematics is to use algebra in every fields of mathematics. But we don't have the exact definition of algebra, and we can't clearly define algebraic thinking. In order to solve this problem, this paper investigate the history of algebra. First, we describe some of the features of proportional Babylonian thinking by analysing some problems. In chapter 4, we consider Greek's analytical method and proportional theory. And in chapter 5, we deal with Diophantus' algebraic method by giving an overview of Arithmetica. Finally we investigate Viete's thinking of algebra through his ‘the analytical art’. By investigating these history of algebra, we reach the following conclusions. 1. The origin of algebra comes from problem solving(various equations). 2. The origin of algebraic thinking is the proportional thinking and the analytical thinking. 3. The thing that plays an important role in transition from arithmetical thinking to algebraic thinking is Babylonian ‘the false value’ idea and Diophantus’ ‘arithmos’ concept.

• 중국학논총
• /
• 제65호
• /
• pp.23-38
• /
• 2020

The dictionary is the most important tool for every Chinese learner to confirm the meaning and usage of words. Therefore, accuracy of headword's interpretation in the dictionary is crucial. This study aims to discuss the accuracy and the adequacy of headwords' interpretation in the Chinese-Korean dictionary through the Chinese corpus and Baidu. The scope of this study are 3000 words in the D3H1 region. According to the research results, the main problems of the vocabulary in this region can be divided into three categories: the first is the problem of lexical interpretation, the second is the problem of missing interpretation, and the third is other problems. In the D3H1 area, there are a total of 719 low-frequency vocabularies, and 54 headword's interpretations are not accurate or appropriate. This study is a detailed investigation and analysis of the problems of these 54 vocabularies.

• International journal of advanced smart convergence
• /
• 제13권2호
• /
• pp.88-93
• /
• 2024

The main problem with existing edge detection techniques is that they have many limitations in detecting edges for complex and diverse images that exist in the real world. This is because only edges of a defined shape are discovered based on an accurate definition of the edge. One of the methods to solve this problem is the cost minimization method. In the cost minimization method, cost elements and cost functions are defined and used. The cost function calculates the cost for the candidate edge model generated according to the candidate edge generation strategy, and if the cost is found to be satisfactory, the candidate edge model becomes the edge for the image. In this study, we proposed an enhanced candidate edge generation strategy to discover edges for more diverse types of images in order to improve the shortcoming of the cost minimization method, which is that it only discovers edges of a defined type. As a result, improved edge detection results were confirmed.

• Journal of the Korean Academy of Child and Adolescent Psychiatry
• /
• 제35권1호
• /
• pp.44-50
• /
• 2024

Parents of children with autism spectrum disorder (ASD) often encounter unique challenges when attempting to understand their children's challenging behaviors such as self-injury, aggression, noncompliance, and stereotypies. In this study, we aimed to analyze and clarify the definition of challenging behaviors in individuals with ASD, identify the variables associated with challenging behaviors, and determine the function of these behaviors. Systematic observation and data collection are crucial to understand the functions of specific behaviors exhibited by individuals with ASD based on their antecedents and consequences. Knowledge regarding these will enable clinicians to develop and implement effective interventions. Additionally, the treatment approach should aim for generalization to improve the quality of lives of both children with ASD and their caregivers.