• Journal of Korean Society of Industrial and Systems Engineering
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• v.37 no.4
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• pp.154-161
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• 2014

In this research we investigate motion controller performance for mobile robots according to changes in the control loop sampling time. As a result, we suggest a proper range of the sample time, which can minimize final posture errors while improving tracking capability of the controller. For controller implementation into real mobile robots, we use a smooth and continuous motion controller, which can respect robot's path curvature limitation. We examine motion control performance in experimental tests while changing the control loop sampling time. Toward this goal, we compare and analyze experimental results using two different mobile robot platforms; one with real-time control and powerful hardware capability and the other with non-real-time control and limited hardware capability.

• Journal of Korean Society of Transportation
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• v.27 no.4
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• pp.115-126
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• 2009

The lane-change behavior usually consists of discretionary lane-change and mandatory lane-change types. For the first type, drivers change lanes selectively to maintain their own driving condition and the second type is the case that the drivers must change the current lane, which can occur in recurrent congestion sections like merging and weaving sections. The mandatory lane-change behavior have a great effect on the operation condition of freeway. In this paper, we first generate data such as traffic volumes, speeds, densities, and the number of lane-change within the merging and weaving sections using the data of individual vehicle collected from time-lapse aerial photography. And then, the data is divided into the stable and congested flow by analyzing the speed variation pattern of individual vehicles. In addition, the number of lane-changing from ramp to mainline within every 30-meter interval is investigated before and after traffic congestion at study sites and the distribution of lane-changing at each 30-meter point is analyzed to identify the variation of lane-changing ratio depending on the stable and congested flows. To recognize the effect of mainline flow influenced by ramp flow, this study also analyzes the characteristics of the lane-changing distributions within the lanes of mainline. The purpose of this paper is to present the basic theory to be used in developing a lane-changing model at the merging and weaving sections on freeways.

• Journal of Biosystems Engineering
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• v.39 no.2
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• pp.101-110
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• 2014

Purpose: The purpose of this study is to develop a system to optimize drying potential energy of the exhausted hot air by changing relative humidity of the air. This study modified the conventional drying method into a drying method changing exhaust cycle and time in order to control the relative humidity of the exhausted hot air during drying process. Method: A valve on the vent was controlled according to a preset time to change the exhaust cycle and time. This study analyzed the influence of the two different types of drying method on the drying characteristics, required energy, and quality of the dried peppers: conventional drying method exhausting hot air continuously and new drying method controlling exhaust cycle and time. Results: Drying characteristics based on exhaust time showed that drying time increased with exhaust time, and specific energy consumption was reduced by 28% from 18.39 MJ/kg (conventional method) to 13.24 MJ/kg when exhaust time was set to one minute. Drying characteristics based on heating time showed that drying time increased with heating time and specific energy consumption was reduced by 30% from 18.39 MJ/kg (conventional method) to 12.87 MJ/kg when exhaust time was set to 22 minutes. Drying characteristics based on exhaust cycle showed that drying time increased with exhaust cycle, and specific energy consumption was reduced by 31% from 18.39 MJ/kg (conventional method) to 12.69 MJ/kg when exhaust time was set to one minute and exhaust cycle was set to 22 minutes before drying and 40 minutes after drying. The quality of the dried red peppers showed that capsaicin, color, and sugar content were high as 34.87 mg/100g, 66.33, and 11.87%, respectively, when exhaust time was set to one minute and exhaust cycle was set to 22 minutes before drying and 40 minutes after drying. Conclusions: In order to utilize the drying potential energy of the exhausted air during drying process, the conventional drying method was modified into the drying method controlling exhaust cycle and time. The results showed that drying with exhaust cycle of one minute was more efficient in terms of drying time, required energy, and quality of the dried peppers than the one with exhaust cycle of 20~40 minutes.

• Journal of architectural history
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• v.20 no.4
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• pp.115-134
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• 2011

International Competition for Parc de la Villette has evoked the old architectural question that is about the conflict between unchanging architecture and ever changing time. Tschumi and Koolhaas suggested well-known solutions for it, both of which had started from the criticism of general urban design approach that ignored changing factors in time. However, this study argues that the approaches of Tschumi and Koolhaas are even opposite to each other in spite of their common aims. Influenced by deconstructivists' theories, Tschumi tries to generate the 'text' on the surface of la Villette so that the different users of the park can read it differently. The text is built by 'superimposing' different systems such as points, lines, and surfaces. This study criticizes such formalistic approach since such 'forms' do not generate any dialogue with the real users but just stay as a backdrop for irrelevant events. Meanwhile, Koolhaas concentrates on the 'ground-ness' of la Villette. What he deals with is the real ground which embraces all the potentials on it already. His 'bands' express nothing but the metamorphosis of the ground, and the ground generates the 'differences' out of itself by repeating itself ceaselessly. This study tries to clarify all those happenings and meanings by intimate investigation of various drawing works for the la Villette project by Tschumi and Koolhaas.

• KIEAE Journal
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• v.11 no.5
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• pp.19-30
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• 2011

This study analysis effects of creativity character on the nation's urban areas and the competitiveness of the urban. The result is that talent of urban creativity effects on the competitiveness of the urban. However, technique and tolerance had not great effect on the competitiveness between cities. After departmentalizing the arrangement of urban creativity, Advanced services constantly appear to affect the competitiveness. Researchers of talent in 2000 and 2005, a culture artistes of tolerance in 2005 and 2009, appeared to affect the competitiveness of urban. In other words, this is changing that the indicators which is impacted on the competitiveness of the urban and each indicator's power with time. According to the result, the study suggests solutions. First, policy direction has to be setting by appropriate the character creativity in urban. Second, there needs the policy which is more focused on talent and tolerance for improving the creativity of urban. For the specific, there needs suggestion about cultural artist and researchers. Finally, considering about changing the urban creativity with time, policy direction has too be setting by reflecting this change.

• Journal of Environmental Policy
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• v.1 no.1
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• pp.1-24
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• 2002

Due to the recent increase in greenhouse gases in atmosphere, world climate is rapidly changing and in turn, the earth ecosystem responds upon the climate changes. Comparing the ecosystem in the past, the present shapes of ecosystem is the result of the serious modification. Fishery resources in marine ecosystem, which usually occupy the upper trophic level, are also inevitable from such changes, because they always react to the natural environmental conditions. The northwestern Pacific is the most productive ocean in the world producing about 30% of world catch. From time to time, however, it has been notified that abundance, distribution and species composition of major fish species were altered by climate events. Furthermore, primary productivity of the ocean is not stable under the changing environments, so that carrying capacity of the ocean varies from one climate regime to another. Major climate events such as global warming, atmospheric circulation pattern, climate regime shift in the North Pacific, and El Nino event in the Pacific tropical waters were introduced in relation to fisheries aspects. The current status and future projection of fishery production was investigated, especially in the North Pacific including Korean waters. This new paradigm, ecosystem response to environmental variability, has become the main theme in marine ecology and fishery science, and the GLOBEC-type researches might provide a solution far cause-effect mechanism as well as prediction capability. Ecosystem management principles for multi-species should be adopted for better understanding and management of ecosystem.

• Korean Journal of Agricultural Science
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• v.31 no.1
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• pp.35-44
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• 2004

In this study, the automatic system exchanging well-plates was developed as a basic stage of the genome project. The developed system consisted of the plate fixing well-plates, the well-plate cassette, the head to move a well-plate from the well-plate cassette to the plate fixing well-plates before genome work or from the plate to the cassette after the work, the manipulator to move the head on the X, Y and Z axes and the control system. The performance test to exchange well-plates with the robotic system developed was carried out. The time to set an well-plate from the well-plate cassette onto the board fixing well-plates was 55 seconds and the time for 9 ones was 8 minutes and 15 seconds. It took 57 seconds to move a well-plate from the board to the cassette and 8 minutes and 33 seconds for 9 ones.

• Journal of the Korean Society of Costume
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• v.32
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• pp.149-162
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• 1997

In this paper it was observed that the influences of social environment that had been saturated by the modern awareness and west-ern culture effected largely on clothing. Also it was studied how and by what en-vironmental factors the costume during the enlightening period was accepted and devel-oped in Korea relative to social cultural en-vironment. In this research the emphasis was placed on the process of changing to western clothing especially the influence of Group Clothing on the general women's clothing. Therefore the types of group clothing and its influences were studied. in this study the types of group clothing recalled were modern women's clothing mission-ary women's clothing professional women's such as nurse uniforms school girls' uniforms and the invention of women's sports wear. And lastly it was searched for the direction of developent in apparels. From the above mentioned we can conclude that the clothing is inseparable from social and cultural Invironments and foreign affairs of politics at the time. Also it is considered that the types of group styles were the necessary happenings in the early stage of modern so-ciety. Because of historical situation in Korea the western clothing style had taken place in a short period of time. however Korean women's clothing which had been centerred around group clothing was considered to have changed from Korean traditional costume to western clothing by rational decisions of modern awareness in-stead of sudden change from traditional clothing to western clothing by indiscrete acceptance of western culture.

• International Journal of Contents
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• v.15 no.4
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• pp.16-26
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• 2019

The efficient implementation of various physical actions of agents to respond to dynamically changing situations is essential for the simulation of realistic agents and activities in a cyber world. To achieve a maximum diversity of actions and immediate responsiveness to abrupt changes in situations, we have developed an animation technique in which complex actions are recursively constructed by reusing a set of primitive motions, and agents are designed to react in real-time to abrupt ambient changes by computationally satisfying kinematic constraints on body parts with respect to their goals. Our reusing scheme is extended to visualize the procedure of realistic intricate situations involving many concurring events. Our approach based on motion reuse and recursive assembly has clear advantages in motion variability and action diversity with respect to authoring scalability and motion responsiveness compared to conventional monolithic (static) animation techniques. This diversity also serves to accommodate the characteristic unpredictability of events concurring in a situation due to inherent non-determinism of associated conditions. To demonstrate the viability of our approach, we implement several composite and parallel actions in a dynamically changing example situation involving events that were originally independent until coincidentally inter-coupled therein.

• Journal of Korean Society of Water and Wastewater
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• v.10 no.4
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• pp.119-126
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• 1996

Influence factors and efficiency characteristics for treatment of wastewater containing phenol were studied with using Pseudomonas sp. B3. It took 130 hours to remove phenol, when only activated sludge of terminal disposal palnt of sewage was innoculated in batch culture, but it was required just 36 hours, when bacteria degrading phenol and activated sludge were simultaneously innoculated. If only phenol an carbon source was used, it necessary 36 hours for biodegradation of phenol, while glucose was added to medium, it took 73 hours. It was revealed as excellent effluent and SVI, when the F/M ratio, COD and phenol concentration were 53mg/l and 1.2mg/l, respectively, and optimum F/M ratio was revealed 0.31. The reactor were seriously shocked as reducing hydraulic retention time at constant phenol concentration more than increasing phenol concentration at constant hydraulic retention time, when volumetric loading rate was increased to $0.8kg\;phenol/m^3{\codt}d$ from $1.6kg\;phenol/m^3{\codt}d$. And also the effluent phenol concentration was 34mg/l after starting 12 hours of shocking and reactor was recovered as steady state after 65 hours of changing in the former test. Although the effluent phenol concentration was maximum value with 12mg/l after starting 20 hours of shocking and reactor was recovered as steady state after 54 hours of changing in the later test.