• International Journal of Control, Automation, and Systems
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• 제4권2호
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• pp.197-203
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• 2006

This paper addresses dynamic modeling and task-space trajectory following issues for nonholonomic mobile manipulators moving on a slope. An integrated dynamic modeling method is proposed considering nonholonomic constraints and interactive motions. An adaptive neural-fuzzy controller is presented for end-effector trajectory following, which does not rely on precise apriori knowledge of dynamic parameters and can suppress bounded external disturbances. Effectiveness of the proposed algorithm is verified through simulations.

• 제어로봇시스템학회논문지
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• 제19권12호
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• pp.1145-1151
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• 2013

Kinematic modeling is a prerequisite for motion planning and the control of mobile robots. In this paper, we proposed a new method of kinematic modeling for a type of mobile robot based on differential motion transformation. The differential motion implies a small translation and rotation in three-dimensional space in a small time interval. Thus, transformation of the differential motion gives the velocity relationship, i.e., Jacobian between two coordinate frames. Since the theory of the differential motion transformation is well-developed, it is useful for the systematic velocity kinematic modeling of mobile robots. In order to show the validity for application of the differential motion transformation, we obtained velocity kinematic models for a type of exemplar mobile robot including spherical ballbots.

• Journal of Korean Biological Nursing Science
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• 제23권3호
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• pp.170-179
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• 2021

Purpose: The aim of this study was to identify core keywords and topic groups in the 'Diabetes mellitus and mobile applications' field of research for better understanding research trends in the past 20 years. Methods: This study was a text-mining and topic modeling study including four steps such as 'collecting abstracts', 'extracting and cleaning semantic morphemes', 'building a co-occurrence matrix', and 'analyzing network features and clustering topic groups'. Results: A total of 789 papers published between 2002 and 2021 were found in databases (Springer). Among them, 435 words were extracted from 118 articles selected according to the conditions: 'analyzed by text network analysis and topic modeling'. The core keywords were 'self-management', 'intervention', 'health', 'support', 'technique' and 'system'. Through the topic modeling analysis, four themes were derived: 'intervention', 'blood glucose level control', 'self-management' and 'mobile health'. The main topic of this study was 'self-management'. Conclusion: While more recent work has investigated mobile applications, the highest feature was related to self-management in the diabetes care and prevention. Nursing interventions utilizing mobile application are expected to not only effective and powerful glycemic control and self-management tools, but can be also used for patient-driven lifestyle modification.

• 대한인간공학회지
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• 제25권2호
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• pp.161-172
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• 2006

This study aims to compare and contrast the Kansei modeling methods for building a luxuriousness model that people feel about appearance of mobile phones. For the evaluation based on Kansei engineering approaches, 15 participants were employed to evaluate 18 mobile phones using a questionnaire. The results of evaluation were analyzed to build luxuriousness models through quantification I method, neural network, and decision tree method, respectively. The performance of Kansei modeling methods was compared and contrasted in terms of accuracy and predictability. The result of comparison of modeling methods indicated that model accuracy and predictability was closely related to the number of variables and data size. It was also revealed that quantification I method was the best in terms of model accuracy while decision tree method was the best modeling method with small variance in terms of predictability. However, it was empirically found that quantification I method showed extremely unstable predictability with small number of data. Consequently, it is expected that the research findings of this study might be utilized as a guideline for selecting proper Kansei modeling method.

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2003년도 가을학술발표대회
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• pp.88-89
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• 2003

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2003년도 가을학술발표대회
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• pp.90-91
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• 2003

• 한국디자인학회:학술대회논문집
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• 한국디자인학회 2003년도 봄 학술발표대회논문집
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• pp.274-275
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• 2003

• 한국콘텐츠학회논문지
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• 제16권2호
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• pp.546-557
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• 2016

치의학 분야에 입문한 학습자가 치아 형태를 이해하고 임상의 기반 기술을 익히기 위해서는 치아카빙 실습이 필요하다. 치아카빙 실습은 단계별 모델을 필요할 때마다 관찰할 수 있을 때 더 효과적이다. 본 연구의 목적은 치아카빙 실습모형을 제안하고, 카빙 단계에 대한 3D모델링 정보를 제공하는 튜토리얼 방식의 모바일 실습지원도구를 개발하는 것이다. 연구결과 치아카빙 실습 모형은 치아형태학 강의 및 실습을 포함하는 강의실 활동과 학습자의 실습과 일상적 학습을 모바일 실습지원도구로 연계하는 모바일 심리스 러닝 형태로 도출하였다. 모바일 실습지원도구는 치아형태학 사전, 치아카빙 실습 튜토리얼, 3D 치아 모델링으로 구현되었다. 개발된 콘텐츠에 대한 전문가 평가 결과 내용 및 기능이 타당하게 설계된 것으로 분석되었다(내용 타당도: 5.0, 인터페이스 타당도: 4.53). 따라서 개발된 모바일 실습지원도구도구는 치아카빙 실습의 모바일 심리스 러닝을 지원하는 데 적합한 학습도구로 판단된다. 본 연구를 기반으로 치의학 분야에 ICT를 활용하는 수업모형과 지원도구인 모바일 콘텐츠 개발 연구가 촉진되기를 기대한다.

• 한국컴퓨터산업학회논문지
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• 제5권9호
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• pp.993-1004
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• 2004

본 논문에서는 구동토크의 제약을 갖는 4륜 2자유도 구륜이동로봇의 기구학 및 동력학 모델링과 경로추적을 다룬다. 유도된 기구학 모델을 이용하여 구륜이퐁로봇의 가제어성을 조사한다. 순간일치좌표계와 힘/토크의 전파, 뉴튼의 평형법칙을 이용하여 동려학 모델을 유도한다. 역동력학에 의해 산출된 구동토크가 한계 구동토크를 초과할 경우, time-scaling 기법을 이용하여 기준제적을 수정함으로써 구륜이동로봇이 기준경로를 추적하도록 한다. 제어기는 모델링 불확실성과 측정 잡음 등으로 인하여 발생하는 오차를 보상하도록 설계한다. 또한 본 논문에서 제시된 기법의 유효성을 입증하기 위해 모의실험을 수행하고 그 결과를 제시한다.

• 한국해양공학회지
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• 제23권2호
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• pp.1-7
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• 2009

This paper presents a sliding mode controller based on Ackermann's formula and applies it to stabilizing a two-wheeled mobile inverted pendulum in equilibrium. The mobile inverted pendulum is a system with an inverted pendulum on a mobile cart. The dynamic modeling of the mobile inverted pendulum was established under the assumptions of a cart with no slip and a pendulum with only planar motion. The proposed sliding mode controller was based upon a class of nonlinear systems whose nonlinear part of the modeling can be linearly parameterized. The sliding surface was obtained in an explicit form using Ackermann's formula, and then a control law was designed from reachability conditions and made the sliding surface attractive to the equilibrium state of the mobile inverted pendulum. The proposed controller was implemented in a Microchip PIC16F877 micro-controller. The developed overall control system is described. The simulation and experimental results are presented to show the effectiveness of the modeling and controller.