• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.41.3-41
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• 2002

Motion estimation using Full-Search(FS) and Block-Matching Algorithm(BMA) is often used in the case of moving object tracking by vision sensors. However these methods often miss the real-time vision data because these schemes suffer the heavy computational load. When the image size of moving object is changed in an image frame according to the distance between the camera of mobile robot and the moving object, the tracking performance of a moving object may decline with these methods because of the shortage of active handling. In this paper, the variable-representative block that can reduce a lot of data computations, is defined and optimized by changing the size of representative block accor...

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.26 no.1
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• pp.27-38
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• 2016

The purpose of this study is to investigate the influence of moving mass on the vibration characteristics and the dynamic response of the simply supported beam. The three types of the moving mass(moving load, unsprung mass, and sprung mass) are applied to the vehicle-bridge interaction analysis. The numerical analyses are then conducted to evaluate the effect of the mass, spring and damper properties of the moving mass on natural frequencies and dynamic responses of the simply supported beam. Particularly, in the case of the sprung mass, variations of the natural frequency of simply supported beam are explored depending on the position of the moving mass and the frequency ratio of the moving mass and the beam. Finally the parametric studies on the resonance phenomena are performed with changing mass, spring and damper parameters through the dynamic interaction analyses.

• Computational Structural Engineering
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• v.22 no.2
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• pp.16-21
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• 2009

• Structural Engineering and Mechanics
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• v.31 no.4
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• pp.477-480
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• 2009

• 한국도로학회지:도로
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• v.13 no.3
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• pp.5-9
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• 2011

• Journal of the Korean Society for Precision Engineering
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• v.18 no.6
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• pp.133-140
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• 2001

This paper suggests another system for a cutting force measuring tool in a milling process. Generally, tool dynamometer is taken into account for the most appropriate cutting force measuring tool in the analysis of cutting mechanism. However, high price and limited space make it difficult to be in-situ system for controllable milling process. Although an alternative method using AC current of servo-motor has been suggested, it is unsuitable for cutting force control because of small upper frequency limit and noise. The cutting force measuring system is composed of two load cells placed between the moving table bracket and the nut flange part of ballscrew. It has many advantages such as low cost and wide range measurement than tool dynamometer because of the built-in moving table and the low cost load cell. The static and dynamic model of the measuring system using imbeded load cell is introduced. Various Experiments are carried out to validate both models. By comparing the cutting forces from a series of end milling experiments on the tool dynamometer and the system developed in this paper, the accuracy of the cutting force measuring system is verified. Upper frequency limit is measured by the experiment of dynamic characteristics.

• Journal of Microbiology and Biotechnology
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• v.20 no.7
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• pp.1140-1151
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• 2010

Differences in DNA banding patterns, obtained by ribosomal intergenic spacer analysis (RISA), and nitrification were followed in a moving-bed biofilm reactor (MBBR) receiving municipal landfill leachate. Complete nitrification (>99%) to nitrate was obtained in the two-stage MBBR system with an ammonium load of 1.09 g N-$NH_4/m^2{\cdot}d$. Increasing the ammonium load to 2.03 g N-$NH_4/m^2{\cdot}d$or more caused a decline in process efficiency to 70-86%. Moreover, at the highest ammonium load (3.76 g N-$NH_4/m^2{\cdot}d$), nitrite was the predominant product of nitrification. Community succession was evident in both compartments in response to changes in ammonium load. Nonmetric multidimensional scaling (NMDS) supported by similarity analysis (ANOSIM) showed that microbial biofilm communities differed between compartments. The microbial biofilm was composed mainly of ammonia-oxidizing bacteria (AOB), with Nitrosomonas europeae and N. eutropha being most abundant. These results suggest that high ammonium concentrations suit particular AOB strains.

• Environmental Engineering Research
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• v.20 no.1
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• pp.65-72
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• 2015

A comparative study on response of a toxic compound thiocyanate ($SCN^-$) was carried out in continuous and fed batch moving bed reactor systems. Both systems had three sequential anaerobic, anoxic and aerobic reactors and operated at same hydraulic retention time. Feed $SCN^-$ was first increased from 600 mg/L to 1,000 mg/L for 3 days (shock 1) and then from 600 to 1,200 mg/L for 3 days (shock 2). In anaerobic continuous reactor, increase of effluent COD (chemical oxygen demand) due to shock load was only 2%, whereas in fed batch reactor it was 14%. In anoxic fed batch reactor recovery was partial in terms of $SCN^-$, phenol, COD and $NO{_3}{^-}$-N and $NO{_2}{^-}$-N removals and in continuous reactor complete recovery was possible. In both systems, inhibition was more significant on aerobic reactors than anaerobic and anoxic reactors. In aerobic reactors ammonia removal efficiency deteriorated and damage was irreversible. Present study showed that fed batch reactors showed higher substrate removal efficiency than continuous reactors during regular operation, but are more susceptible to toxic feed shock load and in nitrifying reactor damage was irreversible.

• Journal of the Ergonomics Society of Korea
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• v.29 no.4
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• pp.495-503
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• 2010

The packing and sorting processes of grape are required repetitive movements to need considerable physical load for a long time. And thereby, there is strong possibility to cause musculoskeletal disorders. In this study, ergonomically designed convenience equipments of worktable and handcart are introduced for improvement of the working movements and less physical load to increase the work efficiency. For objective analysis of the movements and the workload between the ones before and after the improvement, we measured heart rate, OWAS, RULA, REBA, LMM, moving Line and work time. Also, we used a checklist of physical fatigue regions to confirm the subjective evaluation of physical load of workers. As the result of study, it showed lower heart rate, value of Working Postures (OWAS, RULA, REBA) and LMM in the work after introduction of those convenient equipments than the work of before the introduction. The work time and moving Line were shortened and the number of grape boxes packed within the same work time was increased, too. Also the overall load as the subjective evaluation was reduced.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.4
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• pp.809-816
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• 2010

This paper proposed about a load-balanced multi-agent model in mobile distribution environment to monitor moving patients and to deal with a situation of emergency. This model was designed to have a structure based on distribution framework by expanding a mobile system, and provides healthcare services based on real time situational information on moving patients. In order to overcome the limitation of middleware when we design system, we provided an abstract layer between applications and their base network infrastructure so that balance between QoS requests and network life can be maintained. In addition, clustering was used in cells for the efficient load distribution among multi-agents. By using Clustering FCM, we got optimal resources and had solve about transmission delay.