• Journal of the Korean Society for Precision Engineering
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• v.15 no.9
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• pp.158-166
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• 1998

This paper presents a geometrical approach to the characteristic analysis of parallel mechanism with free joints intended for use as a planar task robot. Solution of the forward and inverse kinematic problems are described. Because the mechanism has only three degree-of-freedom output, constraint equations must be generated to describe the inter-relationship between actuated joints and free joints so as to describe the position and orientation of the moving platform. Once these constraints are incorporated into the kinematics model, a constrained Jacobian matrix is obtained. and it is used for the solution of the forward kinematic equations by Newton-Raphson technique. Another Jacobian matrix was derived to describe the interrelationship between actuated joints and moving platform. The stiffness, velocity transmission ratio, force transmission ratio and dexterity of the mechanism are then determined based on this another Jacobian matrix. The geometrical construction of the mechanism for the best performance was investigated using the characteristic analysis.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.13 no.2
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• pp.115-121
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• 2001

Recently, the requirement of healthier and more comfortable environment makes the zoning domain more details. However, it has limitation to satisfy the thermal comfort of an individual because of the effect of the heat generation from the OA machine and partitions in indoor room. In this paper, we certify the validity of task-ambient air-conditioning system that has been developed as a new concept of personal air-conditioning system, and specify design strategies for more efficient task-ambient air-conditioning system with a specification guided by indoor environmental characteristics analyzed through experiment data. In this experiment, we changed the temperature and the quantity of air-flow in task domain to understand characteristic behavior of the thermal environment and investigate the possibility of energy saving. The experiment result is that the environment of the task area depends on the condition of supply air, and though the airflow of the low temperature is supplied with the ambient area, the personal environment and the efficiency of energy saving are improved by controlling the temperature and the quantity of the air shot around the task domain.

• International Journal of Advanced Culture Technology
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• v.11 no.4
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• pp.286-294
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• 2023

We studied learners' perceptions and learning styles of project research activities in the chemical field conducted by 54 science high school students. In a survey of students' perceptions of task research, positive responses were found in "internal motivation," "cooperation," "task solving," and "tenacity and immersion," and statistically significant differences were found in "self-directedness," "cooperation," and "tenacity and immersion" by year. The 'lower' group responded most positively in the 'cooperation' category, and the 'higher' group responded most positively in the 'task solving' category. As a result of investigating the learning styles of the students who conducted the task research, it was found in the order of assimilator, converger, accommodator, and diverger. The assimilators showed the characteristic of systematically and scientifically approaching the problem. Convergers were found to have excellent problem-solving and decision-making ability, are practical, and have experimental-based thinking characteristics. In this study, the characteristics of science high school students showed well in the results of the learning style performed.

• Journal of Elementary Mathematics Education in Korea
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• v.16 no.2
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• pp.253-267
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• 2012

In this paper, we primarily focus on the perspectives about creative process, which is how mathematical creativity emerged, as one aspect of mathematical creativity and then present a desirable task characteristic to measure and program characteristics to develop mathematical creativity. At first, we describe domain-generality perspective and domain-specificity perspective on creativity. The former regard divergent thinking skill as a key cognitive process embedded in creativity of various discipline domain involving language, science, mathematics, art and so on. In contrast the researchers supporting later perspective insist that the mechanism of creativity is different in each discipline. We understand that the issue on this two perspective effect on task and program to foster and measure creativity in mathematics education beyond theoretical discussion. And then, based on previous theoretical review, we draw a desirable characteristic on instruction program and task to facilitate and test mathematical creativity, and present an applicable task and instruction cases based on Geneplor model at the mathematics class in elementary school. In conclusion, divergent thinking is necessary but sufficient to develop mathematical creativity and need to consider various mathematical reasoning such as generalization, ion and mathematical knowledge.

• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.2
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• pp.67-72
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• 2003

A partition integrated air supply system can provide highly personalized environmental control. The supply air is brought up through raised floors and supplied to outlets located on the partition panels. The purpose of this paper is to find out the best design of outlets for optimal occupant comfort within a personal task area. Real scale experiments were conducted to allow for comparisons of outlet designs within a personal task area. Experimental results indicate that the location of an outlet is the most critical factor in improving the efficiency of supply air distribution of a personal task area. Thermal characteristic comparisons were made between the under-floor and the partition supply systems. Experimental results suggest that the partition supply system is more efficient than the under-floor supply system in terms of cooling. Such a system allows occupants to personally control their immediate environment, resulting in higher productivity.

• Journal of Korean Institute of Industrial Engineers
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• v.27 no.3
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• pp.260-266
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• 2001

The characteristic of the random-request availability is that random task arrival is included as one of system elements. If the mean number of task arrivals grows, the computational complexity for deriving the random-request availability becomes extremely high. Using a simulation method, the effect of 'random task arrival' elements on the random-request availability is investigated. Some approximation methods are also discussed.

• 한국공간정보시스템학회:학술대회논문집
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• 2005.11a
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• pp.61-66
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• 2005

Spatiotemporal data mining represents the confluence of several fields including spatiotemporal databases, machine loaming, statistics, geographic visualization, and information theory. Exploration of spatial data mining and temporal data mining has received much attention independently in knowledge discovery in databases and data mining research community. In this paper, we introduce an algorithm Max_MOP for discovering moving sequences in mobile environment. Max_MOP mines only maximal frequent moving patterns. We exploit the characteristic of the problem domain, which is the spatiotemporal proximity between activities, to partition the spatiotemporal space. The task of finding moving sequences is to consider all temporally ordered combination of associations, which requires an intensive computation. However, exploiting the spatiotemporal proximity characteristic makes this task more cornputationally feasible. Our proposed technique is applicable to location-based services such as traffic service, tourist service, and location-aware advertising service.

• Korean Institute of Interior Design Journal
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• v.21 no.1
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• pp.119-126
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• 2012

The purpose of this study is to suggest a strategy of creating sustainable city's streets by extracting a elements related the task related with society, economic, and environment. The method of this study is as follows. First step, we extract main task for developing sustainable settlements through studying literature review. Second step, based on the task for sustainable settlements, we generate various elements for developing sustainable street environments. Third step, we carry out a survey targeting experts related to field of urban environment. Fourth step, we analyze their priority about developing elements and the difference between groups. Last step, through correlation analysis between three task and elements for developing sustainable streets, we discuss the specific application around developing elements. The result of this study is as follows. Firstly, from a social point of view, the task related to connecting of historical and cultural characteristic is the most important thing. In a environmental view, it illustrates that application of technologies based on IT is more important than use of sustainable land. In a economic paint of view, it presents that the elements of city security & disasters are important.

• 제어로봇시스템학회:학술대회논문집
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• 2001.10a
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• pp.155.3-155
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• 2001

Researches of multi-robot system are active in these days. The most remarkable characteristic of multirobot system is that the robots work cooperatively and achieve the task which a single robot cannot do. It is essential to investigate number effect of multi-robot system. In this paper, we chose foraging task and investigated their behavior. At first, we investigated the foraging behavior in case that interaction range is Infinite. Secondly, we investigated the behavior in case that interaction range is finite. In both case, we find out there is an optimum interaction duration.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.19 no.1
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• pp.21-31
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• 2013

Background: The purpose of this survey is to determine the job and task satisfaction of physiotherapists. These are important factors because they are directly connected to both morale and work efficiency. Methods: Data was collected from March 9th, 2013 to April 15th, 2013 using self-administered questionnaires. First, Cronbach Alpha coefficient was used to evaluate date reliability. Further data analysis used mean and standard deviation to determine frequency and satisfaction for each characteristic. To determine the significance of job and task satisfaction, T-test and an analysis of variance were performed. Also, regression analysis was used to find out a relation between job satisfaction of physiotherapist and task satisfaction of orthopaedic physical therapy. Result: This survey includes results from 197 physiotherapists who engage in orthopaedic physical therapy from major, medium and small cities. The general characteristics of survey respondents include: 112 males (56.9%), 85 females (43.1%); 123 in their twenties (62.4%), 56 in their thirties (28.4%), and 18 over forty (9.1%); 156 had less than five years work experience in orthopaedics, 25 had six to ten years, and 16 had more than eleven years work experience. In the physiotherapist's job satisfaction survey (out of 5), males averaged 3.71 and females averaged 3.43. Individuals with less than five years in the career averaged 3.5, 3.69 for between 6 to 10 years in career, 3.87 for over 11 years in career; this showed a significant difference. Results of the sub-factors of job satisfaction were 3.81 for self-esteem and 3.21 for prospect of occupation. Results of task satisfaction in orthopaedic therapy showed a significant difference between 4.03 for males and 3.66 for females. For sub-factors of task satisfaction scores were 3.81 for vision, 4.29 for task adoption, and 3.57 for task recognition. Conclusion: Physiotherapists will be satisfied when their motivation to work and morale are increased by concerns such as improving the education environment, expert physiotherapist adoption issue, and medical law revision.