• Journal of Korean Institute of Industrial Engineers
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• v.31 no.4
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• pp.316-333
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• 2005

Although some successful recognition algorithms have been developed, most of them did emphasize on extracting accurate interpretations without considerations of manufacturability. Evaluating the manufacturability for multiple features leads to produce the machining sequences. In this paper, the A* algorithm guarantees the optimal setup sequences with minimizing the machining cost. Also, tolerances including surface roughness are converted to STEP formats to be utilized for more reliable process plans. Finally, decision tables are used to create the detailed operational sequences based on geometric tolerances and surface roughness. Machining parameters such as feed, depth of cut, and cutting speed for each operation are added to the routing sheet. Windows are presented to show how the entire system works for a sample part.

• Journal of Electrical Engineering and Technology
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• v.13 no.1
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• pp.133-142
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• 2018

Paper presents a comparative study of space vector pulse width modulation (SVPWM) switching sequences for Voltage Source Inverters (VSIs). Various SVPWM switching sequences are studied for two and three level VSIs in linear modulation index region. The computations of dwell times are presented for two and three level VSIs based on space vector geometry in a synchronized and optimized manner. The existing SVPWM switching sequences are implemented using Matlab / Simulink and in an experimental setup for three phase two and three level VSIs. The simulation and experimental waveforms of conventional SVPWM (CSVPWM) and bus clamped SVPWM (BCSVPWM) are demonstrated for two and three level inverter respectively. The performance of different SVPWM switching sequences are evaluated and presented based on weighted voltage total harmonic distortion (THD).

• IE interfaces
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• v.13 no.3
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• pp.388-395
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• 2000

In this paper, we propose an approach for integrated process planning and scheduling through analysis of the alternative operations sequences and machine selection in supply chain with multiple plants. It takes into account such factors alternative machine, alternative operations sequences, setup time, transportation time between plants, along with other manufacturing factors. The objective of the model is to minimize makespan of machine schedules for all parts, determines operations sequence for each part, and selects a machine for each operation simultaneously. Examples are presented to demonstrate the effectiveness of the proposed approach.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.5 s.98
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• pp.29-39
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• 1999

Many industrial products can be assembled in various sequences of assembly operations. To save time and cost in assembly process and to increase the quality of products, it is very important to choose an optimal assembly sequence. In this paper, we propose a methodology that generates an optimal assembly sequence by using the knowledge of experts. First, a product is divided into several sub-assemblies. Next, the disassembly sequences of sub-assembly are generated using disassembly rules and special information can be extracted through the disassembly process. By combining every assembly sequence of sub-assemblies, we can generate all the possible assembly sequences of a product. Finally, the expert system evaluates all the possible assembly sequences and finds an optimal assembly sequence. It can be achieved under consideration of the parameters such as assembly operation, tool change, safety of part. basepart location, setup change, distance, and orientation. The developed system is applied to UBR(Unit Bath Room) example.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.14 no.1
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• pp.8-16
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• 2014

We consider the visual barcode recognition problem in a noisy video data setup. Unlike most existing single-frame recognizers that require considerable user effort to acquire clean, motionless and blur-free barcode signals, we eliminate such extra human efforts by proposing a robust video-based barcode recognition algorithm. We deal with a sequence of noisy blurred barcode image frames by posing it as an online filtering problem. In the proposed dynamic recognition model, at each frame we infer the blur level of the frame as well as the digit class label. In contrast to a frame-by-frame based approach with heuristic majority voting scheme, the class labels and frame-wise noise levels are propagated along the frame sequences in our model, and hence we exploit all cues from noisy frames that are potentially useful for predicting the barcode label in a probabilistically reasonable sense. We also suggest a visual barcode tracking approach that efficiently localizes barcode areas in video frames. The effectiveness of the proposed approaches is demonstrated empirically on both synthetic and real data setup.

• Honam Mathematical Journal
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• v.26 no.2
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• pp.219-236
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• 2004

In this paper, the problem of estimating a p-variate ($p{\geq}4$) normal mean vector is considered in a decision-theoretic setup. Using a simple property of the noncentral chi-square distribution, a sequence of smooth estimators dominating the Lindley type estimator has been produced and each improved estimator is better than previous one.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 2009.01a
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• pp.727-731
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• 2009

In this paper, we propose a method to generate a free viewpoint image using multi-viewpoint images which are taken by cameras arranged circularly. In past times, we have proposed the method to generate a free viewpoint image based on Ray-Space method. However, with that method, we can not generate a walk-through view seen from a virtual viewpoint among objects. The method we propose in this paper realizes the generation of such view. Our method gets information of the positions of objects using shape from silhouette method at first, and selects appropriate cameras which acquired rays needed for generating a virtual image. A free viewpoint image can be generated by collecting rays which pass over the focal point of a virtual camera. However, when the requested ray is not available, it is necessary to interpolate it from neighboring rays. Therefore, we estimate the depth of the objects from a virtual camera and interpolate ray information to generate the image. In the experiments with the virtual sequences which were captured at every 6 degrees, we set the virtual camera at user's choice and generated the image from that viewpoint successfully.

• Nuclear Engineering and Technology
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• v.33 no.1
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• pp.12-24
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• 2001

The post-LOCA long term cooling (LTC) performance of the Korean Standard Nuclear Power Plant (KSNPP) is analyzed for both small break loss-of-coolant accidents (LOCA) and large break LOCA at cold leg. The RELAP5/MOD3.2.2 beta code is used to calculate the LTC sequences based on the LTC plan of the Korean Standard Nuclear Power Plants (KSNPP). A standard input model is developed such that LOCA and the followed LTC sequence can be calculated in a single run for both small break LOCA and large break LOCA. A spectrum of small break LOCA ranging from \ulcorner.02 to 0.5 k2 of break area and a double-ended guillotine break are analyzed. Through the code calculations, the thermal-hydraulic behavior and the boron behavior are evaluated and the effect of the important action including the safety injection tank (SIT isolation and the simultaneous injection in LTC procedure is investigated. As a result, it is found that the sufficient margin is available in avoiding the boron precipitation in the core. It is also found that a further specific condition for the SIT isolation action need to be setup and it is recommended that the early initiation of the simultaneous injection be taken for larger break LTC sequences.

• Journal of the Korean Magnetic Resonance Society
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• v.12 no.2
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• pp.81-88
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• 2008

Solid HETCOR (Hetero-Correlation) requires homo-dipolar decoupling between proton spins during the evolution and the mixing period in 2D-NMR. There are two different ways of achieving it with pulse sequences. One is based on the multiple pulse (MP) sequence where thousands of intense radio frequency (rf) pulses are used to remove the homo-dipolar interaction between protons. The other is utilizing the so-called Lee-Goldburg (LG) off-resonance scheme where a continuous rf-irradiation is used. In this report, the advantage of one technique to the other, is analyzed. LG version is evaluated better in S/N and easier in setup procedure with the same experimental time.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.32A no.12
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• pp.1-8
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• 1995

In this paper, we propose an extendible copy network in a large-scale ATM switch consisting of small switch modules implementable on a single VLSI chip or a single PCB. Considering multicasting switches consist of a copy network and a routing network, there exist broadcast and group translators (BGT) which assign the destination addresses into copied cells. The BGT table can be reduced by vertical partitioning method; copied cells are translated in adjacent BGTs and each BGT table has a single destination address per connection. In addition, the distribution network routes and copies incomming cells into several groups statically which are translated into consecutive BGTs. This guarantees the integrity of cell sequences. Connection-setup time as well as the BGT table size can be reduced significantly.