• Journal of the Korean Ceramic Society
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• v.40 no.4
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• pp.365-370
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• 2003

The phase development process of $Ba_2$ $Ti_{9}$ $O_{20}$ ceramics is not clearly known and frequently accompanies second phases which deteriorate dielectric properties. In synthesizing $Ba_2$ $Ti_{9}$ $O_{20}$ ceramics, in order to trace the reaction sequence during conventional solid-state reaction in BaO-Ti $O_2$ system, different barium sources of BaC0$_3$ and BaTi0$_3$ precursor were used as starting materials. From the analysis of XRD patterns, different secondary phases could be identified depending on the barium source used, which might mean that the equilibrium phases in BaO-Ti $O_2$ system are very difficult to be synthesized. Because the BaTi0$_3$ precursor provides short diffusion paths of ions, the system revealed less secondary phases during solid state reaction. In synthesizing BaO-xSm$_2$0$_3$-4.5Ti0$_2$ system using different barium sources, different secondary phases were developed also. Microstructure and dielectric properties were examined and discussed in terms of secondary phase development.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.22 no.5
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• pp.740-746
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• 2018

Up until now, attempts to produce computer instruments have been largely focused on two types of sampling methods and physical modeling. Since the sampling method removes much of the harmonics in the sampling process, the effect of exciter that emphasizing the harmonic of the strings are mini. However, the physical modeling method can produce a lot of harmonics, and by emphasizing the harmonics of a particular frequency band among these harmonics, it is possible to produce a sound more like a lively sound. In this paper, we propose a method of using white noise in realizing exciter emphasizing harmonics of pre - specified frequency band in prefectural physical modeling. And comparing the envelope and spectrum of the Gayageum sound, we confirmed that the physical modeling method with the exciter is more suitable for the actual Gayageum sound than the sampling method and the conventional physical modeling method.

• Journal of Microbiology and Biotechnology
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• v.22 no.9
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• pp.1253-1257
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• 2012

A gene (acas) designated as ${\alpha}$-amylase was cloned from Arthrobacter chlorophenolicus A6. The multiple amino acid sequence analysis and functional expression of acas revealed that this gene really encoded an amylosucrase (ASase) instead of ${\alpha}$-amylase. In fact, the recombinant enzyme exhibited typical ASase activity by showing both sucrose hydrolysis and glucosyltransferase activities. The purified enzyme has a molecular mass of 72 kDa and exhibits optimal hydrolysis activity at $45^{\circ}C$ and a pH of 8.0. The analysis of the oligomeric state of ACAS with gel permeation chromatography revealed that the ACAS existed as a monomer.

• Journal of Korean Society of Water and Wastewater
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• v.26 no.3
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• pp.431-442
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• 2012

The purpose of this study, is to separate magnetic separation devices using permanent magnets by using magnetization characteristics remaining in treated water after adsorption and synthesizing phosphorus adsorbent capable of magnetic separation for efficient removal of phosphorus. The synthesis of the adsorbent which set Zirconium(Zr) having high friendly features for phosphorus as an element, and by synthesizing Iron Oxide($Fe_3O_4$, another name of $Fe_3O_4$ is magnetite) being able to grant magnetism to Zirconium Sulfate($Zr(SO_4)_2$), zirconium magnetic adsorbent(ZM) were manufactured. In order to consider the phosphorus adsorption characteristics of adsorbent ZM, batch adsorption experiment was performed, and based on the results, pH effect, adsorption isotherm, adsorption kinetics, and magnetic separation have been explore. As the experiment result, adsorbent ZM showed a tendency that the adsorption number was decreased rapidly at pH 13; however, it was showed a high amount of phosphorus removal in other range and it showed the highest amount of phosphorus removal in pH 6 of neutral range. In addtion, the Langmuir adsorption isotherm model is matched well, and D-R adsorption isotherm model is ranged 14.43kJ/mol indicating ion exchange mechanism. The result shown adsorption kinetics match well to the Pseudo-second-order kinetic model. The adsorbent ZM's capablility of regenerating NaOH and $H_2SO_4$, was high selectivity on the phosphorus without impacts on the other anions. The results of applying the treated water after adsorption of phosphorus to the magnetic separation device by using permanent magnets, shows that capture of the adsorbent by the magnetization filter was perfect. And they show the possibility of utilization on the phosphorus removal in water.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.4
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• pp.614-623
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• 1994

Synthesizing speech and facial images is necessary for human interface that man and machine converse naturally as human do. The target of this paper is synthesizing the facial images. In synthesis of the facial images a three-dimensional (3-D) shape model of the face is used for realizating the facial expression variations and the lip shape variations. The various facial expressions and lip shapes harmonized with the syllables are synthesized by deforming the three-dimensional model on the basis of the facial muscular actions. Combications with the consonants and the vowels make 14.364 syllables. The vowels dominate most lip shapes but the consonants do a part of them. For determining the lip shapes, this paper investigates all the syllables and classifies the lip shapes pattern according to the vowels and the consonants. As the results, the lip shapes are classified into 8 patterns for the vowels and 2patterns for the consonants. In advance, the paper determines the synthesis rules for the classified lip shape patterns. This method permits us to obtain the natural facial image with the various facial expressions and lip shape patterns.

• The KIPS Transactions:PartA
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• v.9A no.3
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• pp.379-386
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• 2002

This paper presents a scheduling approach for synthesizing pipelined datapaths under resource constraints. Our approach builds up a schedule based on gradual mobility reduction in contrast to other algorithms of previous researches, where an operation being scheduled is selected by using a priority function. The proposed method consists of a scheduling algorithm and a decision algorithm for detecting any violation against resource constraints. Our approach evaluates whether or not a scheduling solution can exist in case an operation temporarily is assigned to the earliest or latest control step among the assignable steps for the operation. If a solution cannot be found, it is impossible to assign the operation to that step due to a violation against resource constraints, and so we can eliminate that control step. This process is iterated until a reduction of mobility for all operations can not be obtained. Experiments on benchmarks show that this approach gains a considerable improvement over those by previous approaches.

• The Journal of Engineering Geology
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• v.22 no.3
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• pp.293-307
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• 2012

Shear wave velocity is commonly invoked in explaining geophysical phenomena and in solving geotechnical engineering problems. In particular, the importance of shear wave velocity in geotechnical earthquake engineering has been widely recognized for seismic design and seismic performance evaluation. In the present study, various insitu seismic tests were performed to evaluate geotechnical dynamic characteristics at 183 sites in Korea, and shear wave velocity profiles with depth were determined to be representative of the dynamic properties at the investigated sites. Subsurface soil and rock layers at the target sites were reclassified into five geotechnical layers: fill, alluvial soil, weathered soil, weathered rock, and bedrock, taking into account their general uses in geotechnical earthquake engineering practice. Average shear wave velocity profiles for the five geotechnical layers were obtained by synthesizing the shear wave velocity profiles from seismic tests in the field. Based on the profiles, a representative shear wave velocity value was determined for each layer, for use in engineering seismology and geotechnical earthquake engineering.

• Journal of Digital Contents Society
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• v.18 no.4
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• pp.723-731
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• 2017

The restoration of archaeological data was carried out using photographs and drawings left as past records. It can be divided into ruins and artifacts. The restoration of the ruins was performed by modeling the individual parts and parts left by the photographs, aligning them and synthesizing them, and reconstructing them three-dimensionally as one object. Restoration of artifacts was performed on both photographs and drawings. After the modeling work is prioritized through the photographs, there is a method of restoring the original image by modifying the texture image of the damaged part of the modeled artifact, or restoring the original image by modeling and synthesizing the deleted part in the artifact. The restoration of the artifacts through the drawings was carried out by three - dimensional modeling and reconstruction through real mapping of images. The reconstructed archaeological data can be used in various directions. In particular, it is possible to verify and compare the results of the numerical analysis and interpretation of the past 2D data, and to provide a more accurate analysis plan in the future.

• Journal of the Korean Chemical Society
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• v.36 no.2
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• pp.305-310
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• 1992

(${\eta}^5$-Cyclopentadienyl)bis(ethylene)cobalt (Jonas reagent), (${\eta}^5$-cyclopentadienyl)di(carbonyl)cobalt, and bis(${\eta}^5$-cyclopentadienyl)cobalt (cobaltocene) were reacted with oximes, respectively, under various conditions for synthesizing cobalt oxime sandwich complex. Jonas reagent and a dienemonooxime, 2,4-hexadienealdoxime underwent the reaction. This produced unexpected compound, (${\eta}^5$-cyclopentadienyl)(2,4-hexadienenitrile)cobalt [VII]. The compound [VII] was identified by NMR, mass spectrometer, IR and elemental analyzer etc.

• Journal of the Society of Naval Architects of Korea
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• v.28 no.2
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• pp.174-186
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• 1991

There exist many frame structural systems which may be regarded as a combined structural system composed of beam/bar elements and attachments reducible to damped spring-mass systems. In this paper, analytical methods based on the receptance for the vibration analysis of such a system are presented. For the free vibration analysis and response calculations to point excitations, receptances of a uniform Timoshenko beam and a bar are derived in closed and spectral forms, and the method to obtain the system receptance by synthesizing the receptances of the elements and other subsystems is presented. The system damping property is also obtainable by sysnthesizing the components' damping properties. For calculations of the system responses to support motion, the Support Displacement Transfer Ratio(SDTR) of a uniform Timoshenko beam and a bar conceptually similar to the receptance is defined, and the method of synthesizing them with other subsystems' receptances is also presented. Such a method is very convenient especially in dynamic reanalysis subject to changes of some design variables.