• Advances in Computational Design
• /
• v.4 no.3
• /
• pp.197-210
• /
• 2019

Motion generation of a four-bar linkage is a type of mechanism synthesis that has a wide range of applications such as a pick-and-place operation in manufacturing. In this research, the use of meta-heuristics for motion generation of a four-bar linkage is demonstrated. Three problems of motion generation were posed as a constrained optimization probably using the weighted sum technique to handle two types of tracking errors. A simple penalty function technique was used to deal with design constraints while three meta-heuristics including differential evolution (DE), self-adaptive differential evolution (JADE) and teaching learning based optimization (TLBO) were employed to solve the problems. Comparative results and the effect of the constraint handling technique are illustrated and discussed.

• Convergence Security Journal
• /
• v.12 no.3
• /
• pp.67-73
• /
• 2012

In this paper, in order to overcome the disadvantage of wireless-based sensor network, a hybrid sensor network using wired and wireless linkage is proposed. Proposed a wired and wireless linkage hybrid sensor network can compensate the defect of poor transmission at the indoor wireless environment, and can be free from interference between a wireless LAN and Bluetooth of the same frequency bandwidth due to an attribute of low-loss transmission at the CATV network. Also, proposed a wired and wireless linkage hybrid sensor network make use of CATV network which is well-built infrastructure, is more efficient to design network, assure a stability and high reliability of the sensor network as providing a stability for an inaccuracy and a predictable transmission link for the existing wireless network.

• Journal of the Korean Society for Precision Engineering
• /
• v.30 no.9
• /
• pp.961-968
• /
• 2013

In this paper, we propose an optimal design for starfish capturing manipulator module with four-bar linkage mechanism. A tool link with compliance is attached on the four-bar linkage, and the tool repeats detaching starfish from the ground and putting it into the storage box. Since the tool is not rigid and the manipulator is operating underwater, the trajectory of the tool tip is determined by its dynamics as well as kinematics. We analyzed the trajectory of the manipulator tool tip by quasi-static analysis considering both kinematics and dynamics. In optimization, the lengths of each link and the tool stiffness are considered as control variables. To maximize the capturing ability, capturing stroke of the four-bar manipulator trajectory is maximized. Reaction force and reaction moment, and other kinematic constraints were considered as inequality constraints.

• Transactions of the Korean Society of Automotive Engineers
• /
• v.6 no.2
• /
• pp.43-53
• /
• 1998

This paper addresses an optimization for reducing a steering error of a rack-and-pinion steering linkage with a MacPherson strut independent front suspension system. The length, orientations and inner joint positions of a tie-rod are selected as design variables and Ackerman geonetry, understeer effect, minimum turn radius, wheel alignment and packaging are considered as design constraints. Nonlinear kinematic analysis of the steering system is performed for calculating the values of cost and constraints, and Augmented Lagrange Multiplier(ALM) method is used for solving the constrained optinization problem. The optimization results show that the steering error are considerably reduced while satisfying all the constraints.

• CDE review
• /
• v.21 no.2
• /
• pp.31-33
• /
• 2015

This paper deals with synthesis of 4 bar linkage by using optimum design. To design 4 bar linkage, overlay method is proposed and for optimization, genetic algorithm is applied with objective function. The accuracy of this method will be determined by errors between real value and test value. We will use Chebychev spacing to get 3 precision positions of input angles. The output angles will be determined by the function that the designer wants input and output relations to be. It will be applied to example to show the accuracy of this method. The advantages of using this method are that it is fast to get optimal solution and it is simple to use.

• Proceedings of the KSME Conference
• /
• 2001.06b
• /
• pp.313-318
• /
• 2001

A haptic hand controller operated by the user's hand can receive information on position and orientation of the hand and display force and moment generated in the virtual environment to the hand. This paper presents a design method for KU-HHC, 6 DOF Korea University-haptic hand controller, which allows separation of workspace from linkage mechanism in consideration of the efficient user operation. First, the 3 DOF mechanism in which all the actuators are mounted on the fixed base is developed by combining a 5-bar linkage and gimbal mechanism. Then, the 6 DOF HHC is designed by connecting the two 3 DOF devices through a handle. This paper presents the forward and inverse kinematics for this device and Jacobian analysis. Improvement of the kinematic characteristics using performance index is also discussed. The hand controller KU-HHC based on this design concept and kinematic analysis was manufactured and shows excellent performance.

• Asian-Australasian Journal of Animal Sciences
• /
• v.8 no.6
• /
• pp.651-655
• /
• 1995

A simulation study on detection of linkage between genetic markers and QTL in backcross design was conducted. The effects of various sample sizes and the degree of QTL dominance on detention of linkage were examined by using a simple regression analysis. The results indicated that as sample size increased, the standard error of the estimated slope became smaller. When the dominance effect of QTL was complete, the estimated slope tended to be negative but was statistically not significant at all with type I error of greater than 50%. With complete linkage between genetic Marker and QTL, the estimated intercept value was smallest but the estimated slope was largest as expected. In most cases with various degree of dominance and sample sizes, when the actual recombination rate became larger, greater values were obtained for the slope except in the case of complete dominance of QTL.

• Journal of the Korean Society of Safety
• /
• v.35 no.6
• /
• pp.54-60
• /
• 2020

Recently, the issue of construction safety is growing. In the construction industry, accidents have continued to increase since 2000. In particular, the number of accident deaths at small and medium-sized construction sites accounts for 72.11% of the total number of accident deaths in the construction industry. For construction safety, prior safety evaluation systems such as Design for safety and safety management plan preparation are in place. However, at construction sites, these systems are recognized as formal legal documents, and their effectiveness is greatly reduced. Therefore, in this study, a linkage model that links design safety review information and safety management plan information was presented so that the safety management plan can be efficiently established. In addition, the effectiveness of the proposed process was verified as an example of actual work. The linkage model will contribute to improving the safety management environment at the site by increasing the productivity of safety management work by enabling easy sharing of risk factor information in the construction stage safety management work. The results of this study will be used as basic information for the development of the integrated safety management system.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2007.06a
• /
• pp.345-346
• /
• 2007

• Journal of Forest and Environmental Science
• /
• v.36 no.3
• /
• pp.243-254
• /
• 2020

This study was conducted to develop a forest education program through middle school curriculum linkage. We used the ADDIE model, comprising the five phases of Analysis, Design, Development, Implementation and Evaluation, to secure the objectivity of the program. In the Analysis phase, middle school textbooks were analyzed while considering middle school students' needs for curriculum linkage and the developmental stages of adolescents. The Design phase focused on promoting an understanding of curriculum subjects based on what was reviewed in the Analysis phase and concretized and organized a program that can be implemented in the forest, with a focus on science and physical education, based on the results of middle school students' needs. We also established the objectives and goals of curriculum linkage forest education, established the concept of the program, and selected the educational contents, teaching-learning methods, and evaluation methods. In the Development phase, we developed a 2-night, 3-day program linkage with the middle school curriculum and created a manual for instructors and a workbook for students. In the Implementation phase, we revised and supplemented the program through the first test operation with 24 students in their second year of middle school, after which, we carried out a six-session program for the 2-night, 3-day as the second test operation with 17 students in their second year of middle school. In the Evaluation phase, the program was evaluated by the students who participated in the second test operation using questionnaires on satisfaction and curriculum linkage understanding as well as rating scales for attitudes toward forests and environmental sensitivity. The results showed that middle school students showed positive significance in satisfaction and understanding of the middle school curriculum as well as attitudes toward forests and environmental sensitivity through the forest education program.