• Journal of Korean Association for Spatial Structures
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• v.3 no.2 s.8
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• pp.77-83
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• 2003

This paper presents decision making method of structural multi-objective fuzzy optimum problem. The data and behavior of many engineering systems are not know precisely and the designer is required to design the system in the presence of fuzziness in the multi-goals, constraints and consequences of possible actions. In this paper, in order to find a satisfactory solution, the membership functions are constructed for the fuzzy objectives subject to the fuzzy constraints, and two approaches are presented by using the different types of fuzzy decision making. Thus, multi-objective fuzzy optimum problem can be converted into single objective non-fuzzy optimum problem and satisfactory solution of the multi-objective fuzzy optimum problem can be found with general optimum programming. Illustrative numerical example of the ten bar truss for minimum weight and minimum deflection is provided to demonstrate the process of finding the solution and the results are discussed.

• Mycobiology
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• v.44 no.2
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• pp.93-98
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• 2016

A new leaf spot disease was observed on leaves of Rheum palmatum (Chinese rhubarb) in Northwest China (Gansu Province) starting in 2005. A Septoria-like fungus was isolated and completion of Koch's postulates confirmed that the fungus was the casual agent of the leaf spot disease. Morphology and molecular methods were combined to identify the pathogen. The fungus produced conidiomata pycnidia and the conidia were 2~5 septate, $61.2{\sim}134.1{\mu}m$ in length and $3.53{\sim}5.3{\mu}m$ in width, which is much larger than the known Spetoria species that infects Polygonaceae species. Phylogenic analysis of the internal transcribed spacer region confirmed that this Septoria-like fungus is within the Septoria genus but distinct from known Septoria species. Together, these morphological and phylogenetic data support that the R. palmatum infecting Septoria strain is a newly-described plant pathogenic species.

• International Journal of Precision Engineering and Manufacturing
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• v.9 no.4
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• pp.79-82
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• 2008

A method is described for ideally reconstructing the profile from a surface profiling measurement containing a reasonable amount of null measurement data. The proposed method can conjecture lost information and rectify irregular data that result due to bad measuring environments, signal transmission noise, or instrument-induced errors, The method adopts the concept of computer graphics and consists of several processing steps. First, a search for valid data in the neighborhood of the null data is performed. The valid data are then grouped and their contours are extracted. By analyzing these contours, a bounding box can be obtained and the general distribution of the entire area encompassing the valid and null data is determined Finally, an ideal surface model is overlaid onto the measurement results based on the bounding box, generating a complete reconstruction of the calculations, A surface-profiling task on a liquid crystal display photo spacer is used to verify the proposed method. The results are compared to those obtained through the use of a scanning electron microscope to demonstrate the accuracy of the proposed method.

• Nuclear Engineering and Technology
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• v.49 no.8
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• pp.1617-1628
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• 2017

In the passive residual heat removal system of a molten salt reactor, one of the residual heat removal methods is to use the thimble-type heat transfer elements of the drain salt tank to remove the residual heat of fuel salts. An experimental loop is designed and built with a single heat transfer element to analyze the heat transfer and flow characteristics. In this research, the influence of the size of a three-layer thimble-type heat transfer element on the heat transfer rate is analyzed. Two methods are used to obtain the heat transfer rate, and a difference of results between methods is approximately 5%. The gas gap width between the thimble and the bayonet has a large effect on the heat transfer rate. As the gas gap width increases from 1.0 mm to 11.0 mm, the heat transfer rate decreases from 5.2 kW to 1.6 kW. In addition, a natural circulation startup process is described in this paper. Finally, flashing natural circulation instability has been observed in this thimble-type heat transfer element.

• Journal of Microbiology and Biotechnology
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• v.26 no.2
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• pp.373-384
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• 2016

The membrane-aerated biofilm reactor (MABR) is a promising municipal wastewater treatment process. In this study, two cross-flow MABRs were constructed to explore the carbon and nitrogen removal performance and bacterial succession, along with changes of influent loading shock comprising flow velocity, COD, and NH₄-N concentrations. Redundancy analysis revealed that the function of high flow velocity was mainly embodied in facilitating contaminants diffusion and biosorption rather than the success of overall bacterial populations (p > 0.05). In contrast, the influent NH₄-N concentration contributed most to the variance of reactor efficiency and community structure (p < 0.05). Pyrosequencing results showed that Anaerolineae, and Beta- and Alphaproteobacteria were the dominant groups in biofilms for COD and NH₄-N removal. Among the identified genera, Nitrosomonas and Nitrospira were the main nitrifiers, and Hyphomicrobium, Hydrogenophaga, and Rhodobacter were the key denitrifiers. Meanwhile, principal component analysis indicated that bacterial shift in MABR was probably the combination of stochastic and deterministic processes.

• International Journal of Control, Automation, and Systems
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• v.4 no.5
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• pp.637-644
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• 2006

Biomedical image is often complex. An applied image analysis system should deal with the images which are of quite low quality and are challenging to segment. This paper presents a framework for color cell image segmentation by learning and classification online. It is a robust two-stage scheme using kernel method and watershed transform. In first stage, a two-class SVM is employed to discriminate the pixels of object from background; where the SVM is trained on the data which has been analyzed using the mean shift procedure. A real-time training strategy is also developed for SVM. In second stage, as the post-processing, local watershed transform is used to separate clustering cells. Comparison with the SSF (Scale space filter) and classical watershed-based algorithm (those are often employed for cell image segmentation) is given. Experimental results demonstrate that the new method is more accurate and robust than compared methods.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.2
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• pp.44-51
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• 2008

In this paper, we propose a modified clipping scheme for iterative decoding of superposition coding system by losing less power than clipping scheme. Our proposed scheme in superposition coding system shows good performance in peak-to-average power ratio(PAPR) and system performance with the same Clipping Ratio especially in low Clipping Ratio case. Finally in order to alleviate the performance degradation due to clipping noises, we combine a soft compensation algorithm that is combined with soft-input-soft-output(SISO) decoding algorithms in an iterative manner proposed by [1][2]. Simulation results show that with the proposed scheme, most performance loss can be recovered.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.45 no.2
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• pp.97-102
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• 2008

In this paper, we address the OFDM based on DFT or DCT in Cognitive Radio system. An adaptive OFDM based on DFT or DCT in Cognitive Radio system has the capacity to nullify individual carriers to avoid interference to the licensed users. Therefore, there could be a considerably large number of zero-valued inputs/outputs for the IDFT/DFT or IDCT/DCT on the OFDM transceiver. Hence, the standard methods of DFT and DCT are no longer efficient due to the wasted operations on zero. Based on this observation, we present a transform decomposition on two dimensional(2-D) systolic array for IDFT/DFT and IDCT/DCT, this algorithm can achieve an efficient computation for OFDM in Cognitive Radio system

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1112-1114
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• 2009

In this paper, we have studied manufacturing process for liquid crystal displays (LCDs) using plastic substrates. Because the thermal and dimensional stabilities of plastic substrates are decisive issues, both the process and materials were improved to fit the manufacturing requirements of flexible twisted-nematic (TN) and color super-twisted nematic (CSTN) LCDs. Finally, to broaden the flexible display applications, we take advantage of the unique properties of flexible display to design several innovative products.

• Computers and Concrete
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• v.15 no.1
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• pp.37-54
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• 2015

In general, cracks significantly deteriorate the in-situ performance of concrete members and structures, especially in urban metro tunnels that have been embedded in saturated soft soils. The microcapsule self-healing method is a newly developed healing method for repairing cracked concrete. To investigate the optimal microcapsule parameters that will have the best healing effect in concrete, a 3D analytical probability healing model is proposed; it is based on the microcapsule self-healing method's healing mechanism, and its purpose is to predict the healing efficiency and healing probability of given cracks. The proposed model comprehensively considers the radius and the volume fraction of microcapsules, the expected healing efficiency, the parameters of cracks, the broken ratio and the healing probability. Furthermore, a simplified probability healing model is proposed to facilitate the calculation. Then, a Monte Carlo test is conducted to verify the proposed 3D analytical probability healing model. Finally, the influences of microcapsules' parameters on the healing efficiency and the healing probability of the microcapsule self-healing method are examined in light of the proposed probability model.