• Journal of the Korea Society of Computer and Information
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• v.13 no.3
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• pp.27-33
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• 2008

In this paper, we propose a method of automatically constructing a dictionary by extracting unknown words from given eojeols in order to improve the performance of a Korean morphological analyzer. The proposed method is composed of a dictionary construction phase based on full text analysis and a dictionary construction phase based on web document frequency. The first phase recognizes unknown words from strings repeatedly occurred in a given full text while the second phase recognizes unknown words based on frequency of retrieving each string, once occurred in the text, from web documents. Experimental results show that the proposed method improves 32.39% recall by utilizing web document frequency compared with a previous method.

• Journal of Korea Society of Industrial Information Systems
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• v.7 no.3
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• pp.74-80
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• 2002

There are many researches on post-processing methods for the Korean continuous speech recognition enhancement using natural language processing techniques. It is very difficult to use a formal morphological analyzer for improving the speech recognition because the analysis technique of natural language processing is mainly for formal written languages. In this paper, we propose a speech recognition enhancement model using syntactic unit of morphemes. This approach uses the functional word level longest match which dose not consider spacing words. We describe the post-processing mechanism for the improving speech recognition by using proposed model which uses the relationship of phonological structure information between predicates md auxiliary predicates or bound nouns that are frequently occurred in Korean sentences.

• Journal of Powder Materials
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• v.22 no.2
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• pp.87-92
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• 2015

Metallic porous materials have many interesting combinations of physical and geometrical properties with very low specific weight or high gas permeability. In this study, highly porous Cu foam is successfully fabricated by a slurry coating process. The Cu foam is fabricated specifically by changing the coating amount and the type of polyurethane foam used as a template. The processing parameters and pore characteristics are observed to identify the key parameters of the slurry coating process and the optimized morphological properties of the Cu foam. The pore characteristics of Cu foam are investigated by scanning electron micrographs and micro-CT analyzer, and air permeability of the Cu foam is measured by capillary flow porometer. We confirmed that the characteristics of Cu foam can be easily controlled in the slurry coating process by changing the microstructure, porosity, pore size, strut thickness, and the cell size. It can be considered that the fabricated Cu foams show tremendous promise for industrial application.

• Journal of KIISE:Software and Applications
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• v.27 no.4
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• pp.441-447
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• 2000

Automatic word spacing is needed to solve the automatic indexing problem of the non-spaced documents and the space-insertion problem of the character recognition system at the end of a line. We propose a word spacing algorithm that automatically finds out word spacing positions. It is based on the recognition of Eojeol components by using the sentence partition and bidirectional longest-match algorithm. The sentence partition utilizes an extraction of Eojeol-block where the Eojeol boundary is relatively clear, and a Korean morphological analyzer is applied bidirectionally to the recognition of Eojeol components. We tested the algorithm on two sentence groups of about 4,500 Eojeols. The space-level recall ratio was 97.3% and the Eojeol-level recall ratio was 93.2%.

• Journal of the Korean Society of Combustion
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• v.9 no.2
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• pp.38-44
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• 2004

The evolution of incipient soot particles has been examined by high resolution electron microscopy (HRTEM) and elemental analyzer in ethylene-air inverse diffusion flames. Laser Induced Incandescence(LII) and laser scattering methods were introduced for examining the soot volume fraction and morphological properties in combustion generated soot qualitatively. Soot particles, collected by thermophoretic sampling, were analyzed by using HRTEM to examine the nano structure of precursor particles. HRTEM micrographs apparently reveal a transformation of condensed phase of semitransparent tar-like material into precursor particles with relatively distinct boundary and crystalline which looks like regular layer structures. During this evolution histories, C/H analysis was also performed to estimate the chemical evolution of precursor particles. The changes of C/H ratio of soot particles with respect to residence time can be divided into two parts: one is a very slowly increasing regime where tar-like materials are transformed into precursor particles (inception process) the other is an increasing region with constant rate where surface growth affects the increase of C/H ratio dominantly (surface growth process). These results provide a clear picture of a transition to mature soot from precursor materials.

• Journal of Acupuncture Research
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• v.23 no.5
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• pp.199-206
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• 2006

Objectives : The aim of this study was to investigate the effect of various electroacupuncture stimulation on neuronal nitric oxide synthase(nNOS) in cerebral cortex, brain stem, cerebellum of spontaneously hypertensive rats. Methods : We evaluated the changes of nNOS-positive neurons using a immunohistochemical method. The staining intensity of nNOS positive neurons was assessed in a quantitative fashion using a microdensitometrical method based on optical density by means of an image analyzer. Results : The average optical density of nNOS-positive neurons of 100 Hz (bipolar square wave 0.2 ms duration and 100 Hz frequency) electroacupuncture treatment group significantly decreased in most cortical areas comparison between the manual acupuncture and 2 Hz (bipolar square wave 0.2 ms duration and 2 Hz frequency) electroacupuncture groups. In the brain stem, the optical density of nNOS-positive neuron at superficial gray layer of the superior colliculus area, dorsolateral periaqueductal gray area and paralemniscal nucleus were same as cerebral cortex. Conclusion : We conclude that the morphological evidence for nNOS-positive neurons may be have regional change in cerebral cortex brain stem and cerebellum according to various electroacupuncture stimulations.

• Journal of Acupuncture Research
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• v.18 no.4
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• pp.116-124
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• 2001

Background and Objetive : The aim of this study was to investigate the effect of various electroacupuncture stimulation on NADPH-diaphorase in cerebral cortex, brain stem, cerebellum of spontaneously hypertensive rats. Materials and Methods : We evaluated the changes of NADPH-d-positive neurons using a histochemical method. The staining intensity of NADPH-d-positive neurons was assessed in a quantitative fashion using a microdensitometrical method based on optical density by means of an image analyzer. Results and Conculsion : The average optical density of NADPH-d-positive neurons of 100 Hz (bipolar square wave 0.2 ms duration and 100 Hz frequency) electroacupuncture treatment group significantly increased in most cortical areas comparison between the manual acupuncture and 2 Hz (bipolar square wave 0.2 ms duration and 2 Hz frequency) electroacupuncture groups. In the brain stem, the optical density of NADPH-d-positive neuron at only superficial gray layer of the superior colliculus area was same as cerebral cortex. We conclude that the morphological evidence for NADPH-d-positive neurons may be have regional change in cerebral cortex brain stem and cerebellum according to various electroacupuncture stimulations.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.11 no.2
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• pp.43-48
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• 2001

GaN micro-crystals were synthesized through the direct reaction of $NH_3$with a Ga-melt. The bubbling technique in the atmospheric $NH_3$ ambient was employed and dark-gray-colored GaN micro-crystals with various sizes ranging from 0.5~30$\mu \textrm{m}$ were obtained. It was confirmed that product yield increased with increasing reaction temperature. The synthesized GaN micro-crystals were characterized by using a particle size analyzer, SEM, XRD and PL. The variation of reaction temperature from $850^{\circ}C$ to $1150^{\circ}C$ result in morphological change and in optical characteristics of GaN micro-crystals. Especially; GaN micro-crystals synthesized at 10sec showed the highest crystallinity and low yellow band luminescence.

• Proceedings of the KSME Conference
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• 2004.11a
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• pp.1172-1177
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• 2004

The evolution of incipient soot particles has been examined by high resolution electron microscopy (HRTEM) and elemental analyzer in ethylene-air inverse diffusion flames. Laser Induced Incandescence(LII) and laser scattering methods were introduced for examining the change of soot volume fraction and morphological properties in combustion generated soot qualitatively. Soot particles, collected by thermophoretic sampling were analyzed by using HRTEM to examine the nano structure of precursor particles. HRTEM micrographs apparently reveal a transformation of condensed phase of semitransparent tar-like material into precursor particles with relatively distinct boundary and crystalline which looks like regular layer structures. During this evolution histories C/H analysis was also performed to estimate the chemical evolution of precursor particles. The changes of C/H ratio of soot particles with respect to residence time can be divided into two parts: one is a very slowly increasing regime where tar-like materials are transformed into precursor particles (inception process) the other is an increasing region with constant rate where surface growth affects the increase of C/H ratio dominantly (surface growth region). These results provide a clear picture of a transition to mature soot from precursor materials.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.462-463
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• 2018

Traditional document analysis systems used word-based analysis using a morphological analyzer or TF-IDF technique. These systems have the advantage of being able to derive key keywords by calculating the weights of the keywords. On the other hand, it is not appropriate to analyze the contents of documents due to the structural limitations. To solve this problem, the proposed algorithm calculates the weights of the documents in the document and divides the paragraphs into areas. And we calculate the importance of the divided regions and let the user know the area with the most important paragraphs in the document. So, it is expected that the user will be provided with a service suitable for analyzing documents rather than using existing document analysis systems.