• The Transactions of the Korean Institute of Electrical Engineers
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• v.40 no.3
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• pp.299-307
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• 1991

This paper deals with the determination of a firing sequence of transitions in the reachability problem of Safe Petri Net. The determination problem of a firing sequence is very important from the point of practical view, especially in the control of the discrete systems modelled by Safe Petri Net. The determination method of a firing sequence of transitions by means of the matrix equation for the discrete systems modelled by Safe Petri Net is proposed. First, a construction method of the indicence matrix and the firing rule for Safe Petri Net with self-loop are presented by defining the permissive arc in place of self-loop. Next, we develop a method that can find the enable transitions of Safe Petri Net by means of the matrix equation of Safe Petri Net. Finally, by using this method, we propose an algorithm that determines the firing sequence of transitions of Safe Petri Net.

• 제어로봇시스템학회:학술대회논문집
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• 2002.10a
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• pp.106.3-106
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• 2002

1. Introduction 2. Petri-Net 3. Dynamic environment recognition 4. Simulation 5. Conclusion. References

• 제어로봇시스템학회:학술대회논문집
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• 1993.10a
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• pp.1099-1104
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• 1993

The real time control system for FMS(Flexible Manufacturing System) is implemented at this paper. To achieve this goal, the Colored and Timed Petri-Net model is constructed and used to simulate the real time operation of FMS. Using the Colored and Timed Petri-Net model, evaluating any kind of FMS plant is possible. On-line shceduler, intelligent dispatcher, real time monitor and the simulation model of shop floor are contructed using LAN communication, relational database system in this paper. Finally, this real time control system is applied to the FMS/CIM center at Seoul National University.

• Korean Journal of Organic Agriculture
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• v.25 no.3
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• pp.619-630
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• 2017

In recent years, not only the cultivation area of Jujube in Korea but also the number of pest species has increased. The farmers farming environmentally friendly are in great difficulty because there are no effective control devices. This study was conducted to investigate the control effect of the insect screen net on three pest species (Apolygus spinolae, Dasineura sp. and Carposina sasakii) in Jujube orchard when the pests were blocked by insect screen net. For the first and second surveys, the damage rates by A. spinolae were 9.06, 13.95% in 50 mesh, 4.75, 10.17% in 25 mesh, 5.68, 11.84% in 18mesh mesh of insect screen net and 21.6, 36.34% in untreated insect screen net, respectively. The damage rates by Dasineura sp. were 0.54, 0.13% in 50 mesh, 0.93, 2.84% in 25 mesh, 1.05, 13.45% in 18 mesh mesh of insect screen net and 11.1, 26.65% in untreated insect screen net. Carposina sasakii were completely blocked in all the treatments. Damages on Jujube were not observed by insect screen net. Therefore, insect screen net is effective on insect pest control for Jujube.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.11
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• pp.134-143
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• 2007

A new approach based on mean value coordinate combined with Laplacian coordinate is proposed for shape deformation of a large polygon model composed of triangular net. In the method, the spherical mean value coordinates for closed control meshes is introduced to describe a vertex in the triangle meshes to be deformed. Furthermore, the well known quardratic least square method for the Laplacian coordinates is employed in order to deform the control meshes. Because the mean value coordinates are continuous and smooth on the interior of control meshes, deforming operation of control meshes change the shape of polygon model while preserving the intrinsic surface detail. The effectiveness and validity of this novel approach was demonstrated by using it to deform large and complex polygon models with arbitrary topologies.

• Journal of The Korean Society of Agricultural Engineers
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• v.54 no.4
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• pp.93-103
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• 2012

A suction-saturation control technique based on flow pump system was developed to investigate hydraulic properties in unsaturated soils. The flow pump system is designed based on the principle of the axis-translation technique and triaxial equipment, and gives the suction-time and suction-saturation curves, the primary relationship needed for interpreting the response of unsaturated soils and link between theory and the material properties in unsaturated soil mechanics. Using the suction-saturation control technique, suction-time relationship and soil-water retention curve (SWRC) during hydraulic hysteresis were investigated with different net confining pressures and porosities. Three types of soils-two sands and a silt were used in this paper. This paper showed the effect of the hysteresis on the SWRC due to different net confining pressures and porosities. This means that a careful decision must be made as to which condition is to be modeled, since the delicate difference of the conditions in physical modeling can cause the different experimental output.

• Journal of Korea Multimedia Society
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• v.22 no.8
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• pp.823-831
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• 2019

In recent years, there has been developed systems such as a surveillance system and access control using a face recognition function instead of a password or an RFID chip, thereby reducing the risk of falsification. Moreover, deep learning technology has been applied to real-time face recognition technology in video, so it makes possible the development of access control system that improves the accuracy of recognition and efficiency of management. In this paper, we propose a real-time access management system based on face recognition using ResNet. The system is based on web server, which make it possible to manage the access by recognizing the person of the image through the camera and access information stored in the database. It can be accessed by a user application to receive various information. The implemented system identifies a person in real time and allows access control by accurately distinguishing whether they are members or not, and the test results can recognize in 0.2 seconds. The accuracy of recognition rate is up to about 97% depending on the experiment environment. With this system, access can be managed quickly and effectively, even many people rush to it.

• Journal of Bio-Environment Control
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• v.10 no.4
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• pp.219-224
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• 2001

This experiment was conducted to evaluate net mineralization and nitrification in rain shelter soil incorporated with wine sludge. Net mineralization and nitrification rates varied among treatments during pepper growing periods. In general, net mineralization increased up to 90 days after transplanting before its decrease during the rest growing periods. Maximum net mineralization and nitrification in upper 0-15 cm layer soil were observed in T4 at 90 days after transplanting. The greatest amount of mineralization in upper layer soil was 272.5 mg.kg$^{-1}$ at 30 days in the control and 843.3 mg.kg$^{-1}$ at 90 days after transplanting in T4. Overall, both net mineralization and net nitrification were greater in the upper layer soil than in the lower 15-30 cm layer soil.

• Proceedings of the Korean Geotechical Society Conference
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• 2005.03a
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• pp.796-805
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• 2005

Most rockfall prevention net among the rockfall prevention equipment that is constructed in around the road is actuality lack of function by quantitative research insufficiency etc.. Most of rockfall prevention net are composed to setting needle, perpendicular and horizontal wire rope and wire net. Also, function of rockfall prevention net depend on setting needle and the wire net and perpendicular and horizontal wire rope are fixed by setting needle. when unreasonable load is offered setting needle, rockfall prevention net can lose the function and happen continuous falling off of rockfall prevention net. Because rockfall prevention net have a such structural defect, improvement had been required in reply. So in this paper, spot application of Rock Bolt & Net Connection method and falling rock support ability are estimated by numerical analysis. As a result, when Rock Bolt & Net Connection Method is applied to cutting slope, decreases of stress and displacement is examined than current rockfall prevention net.

• Journal of Bio-Environment Control
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• v.5 no.2
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• pp.167-173
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• 1996

Laser distance meter and x-y robot employed in the extraction of three dimensional image recognition of muskmelon net and recognized the characteristics of that. All data measured transmitted to the PC/AT in the computer room and programmed with Visual Basic(Microsoft). Alteration of the concentration and application time of nutrient solution modified the net height and width of hydroponically grown muskmelon. Net height and width which are the characteristics of muskmelon depended on the concentration of nutrient solution used. Decreasing with the concentration of nutrient solution lowered the occupying ratio of net and also observed the tendency of widening of muskmelon net.