• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.7 no.1
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• pp.9-21
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• 1998

This paper a new solution approach to moving obstacle avoidance problem of a mobile robot. A new concept avoidability measure (AVM) is defined to describe the state of a pair of a robot and an obstacle regarding the collision between them. As an AVM, virtual distance function (VDF), is derived as a function of the distance from the obstacle to the robot and outward speed of the obstacle relative to the robot. By keeping the virtual distance above some positive limit value, the robot avoids the obstacle. In terms of the VDF ,an artificial potential field is constructed to repel the robot away from the obstacle and to attract the robot toward a goal location. At every sampling time, the artificial potential field is updated and the force driving the robot is derived from the gradient of the artificial potential field. The suggested algorithm drives the robot to avoid moving obstacles in real time. Since the algorithm considers the mobility of the obstacle as well as the distance, it is effective for moving obstacle avoidance. Some simulation studies show the effectiveness of the proposed approach.

• Journal of Power Electronics
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• v.12 no.1
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• pp.136-144
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• 2012

In this paper, the different techniques for the field weakening, also known as constant power speed range (CPSR) operation, for permanent magnet synchronous motor (PMSM) will be introduced and analysed. Field weakening of PMSM, can be done using either vector control (VC) or conventional phase in advance (CPA). Implementation of these techniques depending on some features and constrains. Most of these features and constrains came from the motor parameters. One of these constrains is the motor inductance which determining whether the motor can be driven in the CPSR or not. A new approach for the field weakening will be discussed and to be verified to overcome this constrain. The new approach will be verified through both techniques VC and CPA.

• Proceedings of the KIEE Conference
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• 1989.11a
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• pp.467-469
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• 1989

A new singular value approach is presented and analized in order to determine the number of multi pie sinsoidal frequencies from the finite noisy data. Simulations are conducted for Akaike's information criterion(AIC), Rissanen's shortest data description(MDL) and a new singular value approach, in covariance matrix based methods. And then performances are compared.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.83.4-83
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• 2001

The paper presents a new closed-form, not a polynomial-form, solution of the direct kinematics of the 3-6 (Stewart-Gough) Platform. Many research works have presented a single high-order polynomial equation of the direct kinematics. However the polynomial equation causes potential problems such as complicated formulation procedures and discrimination of the actual solution from all roots, which results in time-consuming task and heavy computational burden. Thus, to overcome these problems, we use a new formulation approach, based on the Tetrahedron Approach, to derive easily a closed-form nonlinear equation of the direct kinematics and use not the Newton-Raphson method, but the Secant method to obtain quickly the solution from ...

• 제어로봇시스템학회:학술대회논문집
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• 1988.10a
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• pp.231-235
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• 1988

In this paper we present a new method to control system design using a sliding mode. The objective of this research is to develop the algorithm for the sliding mode control which is able to remove the chattering phenomena and to reduce the reaching phase. To accomplish this approach we introduce switching dynamics instead of switching logics to obtain the sliding mode. Consequently, we can obtain the new design approach which is much simpler than the VSS theory. And there do not exist chattering phenomena in this method because the obtained control input are continuous. Simultaneously we can reduce the reaching phase by a suitable choice of design factor. Numerical examples are discussed as illustration.

• Journal of Chest Surgery
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• v.36 no.11
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• pp.883-885
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• 2003

Traditional surgical management of chylothorax refractory to conservative treatment is thoracic duct ligation through a right open thoracotomy. A new surgical procedure of ligation of the thoracic duct via extrapleural approach is presented. Its advantages are less invasive, no need of a new drainage tube, and easier to expose the thoracic duct than the conventional transthoracic approach. We experienced a new surgical method in the treatment of the chylothorax and report it with literatures.

• Journal of Navigation and Port Research
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• v.27 no.2
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• pp.103-109
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• 2003

Evaluating the risk of collision quantitatively plays a key role in developing the expert system of navigation and collision avoidance. This study analysed the existing methods of appraising the collision risk, examined the problem that are intrinsic to them, and developed a new approach to its evaluation by using the sech function as an alternative to them. This paper applied the new method in appraising the collision risk and suggested how to decide the safe range of ownship's action.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.38 no.1
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• pp.43-50
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• 1989

In this paper we present a new approach to control system design for multivariable systems using a sliding mode. In the applications of variable structure system (VSS) theory to multivariable systems, there exist some difficulties such as how to determine switching gains and how to reduce chattering phenomena in input and state trajectories. To cope with these drawbacks we introduce switching dynamics instead of switching logics to obtain the sliding mode. Consequently, we can obtain the new design approach which is much simpler than the VSS theory, And there do not exist chattering phenomena in this method because the obtained control inputs are continuous. Hierarchical control concepts are used to the control system design. Numerical examples are discussed as illustrations.

• PNF and Movement
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• v.13 no.2
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• pp.55-72
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• 2015

Purpose: The purpose of this study was to propose a new therapy algorithm that combines motor imagery and physiotherapy as a physiotherapeutic clinical intervention technique that can stimulate the recovery of damaged physical function for patients with stroke. Methods: A variety of scientific research results related to motor imagery were reviewed and analyzed to investigate their applicability to physiotherapy in clinics. Results: As a new therapy algorithm for the therapeutic approach of motor imagery in stroke rehabilitation, a therapy algorithm that combines motor imagery with physiotherapy is proposed, which consists of three stages or steps: STEP 1 motor imagery familiarization, STEP 2 explicit learning stage, and STEP 3 implicit learning. Conclusion: The new therapy algorithm proposed in this study is expected to be a very useful clinical therapeutic approach for stimulating the recovery of damaged physical function in patients with stroke. It is believed that it will be necessary to confirm and standardize the effects of the therapeutic algorithm proposed in this study in the future by conducting diverse clinical studies.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.573-577
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• 2015

Safety is paramount for construction industry throughout the world. Human errors which contribute to more than half of construction accidents, could be proactively prevented through effective education and training methods. Although Virtual Reality (VR) and Augmented Reality (AR) have gained much attention in various disciplines, few studies applied them for construction safety education. This research presents a new approach in construction safety education by utilizing VR and AR. The vision of aligning teaching & learning strategies is examined in order to ensure the potential benefits of the new method. This innovative approach shifts safety education from "Listen, and I will forget. See, and I may remember" towards "Practice, and I understand".