• The Journal of the Korea Contents Association
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• v.11 no.12
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• pp.597-610
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• 2011

In database application developments, data coexists in memory and disk spaces. To manipulate the memory data, the general programing languages are used and to manipulate the disk data, SQL is used. In particular, the procedural languages for the memory manipulation are difficult to create and manage than declarative languages such as SQL. Thus, this paper shows that a particular structure of memory data, tree structured, can be manipulated by SQL. Most of all, the model data of the user interfaces can be represented by a tree structure and thus, it can be processed by SQL except non set computations. The non set computations could be done by helper classes. The SQL memory data manipulation is more suited to the database application developments which have few complex computations.

• Journal of the Korean Vacuum Society
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• v.16 no.1
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• pp.1-6
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• 2007

We have analyzed the atomic structure of O/Fe(100) and interface atomic structure of MgO deposited on Fe(100) surface using LEED I/V curve analysis. As the O adsorption on the Fe(100) surface, the first substrate interlayer distance is expanded by up to 16%. For 1ML MgO deposited on Fe(100) surface, the oxygen ions of MgO are located on-top of the Fe atoms, the interlayer distance at the MgO/Fe interface are expanded. From the AIA(average intensity mixing approximation) calculation, we find the interface structure of monolayer MgO on Fe(100) system has the two interface structure with MgO/FeO/Fe(100) and MgO/Fe(100). This supports the results of EELS experiment that shown existence of stretched FeO layer and coexistance of MgO/FeO/Fe(100) and MgO/Fe(100) structure.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.16 no.10
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• pp.2150-2162
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• 2012

In accordance with evolution of next-generation mobile Internet, 2G, 3G, 4G, and B4G mobile communication wireless access networks will be co-existed and service providers will be merged as an integrated service provider. In addition, multiple virtual service operators will appear. In order to provide complicated unified-services, in the future Internet, wireless network virtualization where network resource is shared by various service operators is necessary. Therefore, in this paper, we investigate network architectures and virtualization scenarios for wireless access network virtualization where various wireless access technologies are flexibly operated by multiple service providers over next-generation wireless access networks. We expect that the virtualization scenario and network architecture yielded from this study can play a role as a basis for development of wireless access network virtualization algorithms.

• Korean Journal of Materials Research
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• v.9 no.7
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• pp.657-662
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• 1999

Mn-Ni oxide thin films for NTC thermistor application were sputtered on alumina substrates at $320^{\circ}C$ Effects of various oxygen partial pressures and annealing temperatures on the microstructure, crystal phase, resistivity and B constant were investigated. In general, microstructure of the films deposited was columnar grain structure. After annealing at $700^{\circ}C$, the microstructure was begun to transform to equiaxed grain structure. Most of the phases were mixture of cubic spinel and $Mn_2$$O_3$. As the oxygen concentration increased, the resistivity and B constant were greatly decreased, and these values become low and stable after annealing between $600^{\circ}C$ and $700^{\circ}C$.

• Journal of Gifted/Talented Education
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• v.21 no.3
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• pp.595-610
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• 2011

It is hard to understand the coexistence of giftedness and disorder in an individual, but the twice-exceptional is widely recognized now. Gifted autistic spectrum disorder is one of its subtypes in which giftedness exists with autistic spectrum disorder (ASD) simultaneously. Like other constructs including giftedness, the nature of gifted ASD has not been understood in a fundamental and wholistic manner. This paper suggests a cognitive mechanism of gifted ASD based on the integrated model of human abilities(Song, 2009; Song & Porath, 2005), which explains how giftedness coexists with ASD and interacts with each other, producing the characteristics of gifted individuals with ASD. According to the suggested mechanism, the excessive growth of mental spaces in the brain may cause ASD. The over-grown mental spaces result in excessively strong short-term sensory memory and better facility of processing, promoting internal cognitive activities on one hand, but relative lack of cognitive activities in the real world space results in ASD symptoms on the other hand. The cognitive structure of gifted ASD students also contributes to the presentation of giftedness in specific domains. This study suggests that gifted individuals with ASD need to be discouraged from fully engaging in domains they are interested in or the most confident of, rather to be encouraged to invest their giftedness to overcome their ASD symptoms. This study also provides new perspectives on theoretical and educational approaches for gifted ASD.

• Journal of the Korean Magnetics Society
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• v.5 no.1
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• pp.48-53
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• 1995

The structure, magnetic properties and magnetoresistance phenorrena of Ag-Co nano-granular alloy films prepared by a thermal co-evaporation were studied. Supersaturated fee Ag-Co solid solution and fee Co clusters coexisted in the as-deposited state. As Co content increases from 20 to 55 at.% Co, the grain size of the Ag matrix decreases from 147 to $67{\AA}$, and the Co solubility in the Ag matrix increases from 2.5 to 6.7%. Ag-Co alloy films having composition below 25 at.% Co showed mainly superparamagnetic behavior and above that composition, they showed both paramagnetic and ferromagnetic l::ehavior in the as-deposited state. The maximum magnetoresistance of 19% at R. T. and 10 kOe was obtained in the as-deposited 30 at.% Co alloy film. Heat treatment did not improve the MR ratio tecause most of the Co was already precipitated in the as-deposited state.

• Polymer(Korea)
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• v.29 no.1
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• pp.1-7
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• 2005

Interpenetrating polymer network (PN) is a mixture of network polymers. The characteristics of IPN material is the control of morphology during the IPN synthesis. By controlling the relative kinetics of chemical reaction (as well as gellation) and phase separation, the morphology of IPN can be controlled to obtain materials with nano-scale domain and also the co-continuous phase. Other important advantage is the fact that the morphology is permanent due to the presence of the physical interlocking between the networks. The combination of hydrophilic polyurethane and hydrophobic polystyrene in IPN form provides enhanced blood compatibility due to the co-existence of the hydrophilic and hydrophobic domains in nano-scale on the surface. The reaction temperature, reaction pressure and the degree of crosslinking were varied during the IPN synthesis and the morphology and blood compatibility of the resulting IPN materials were studied.

• Journal of agriculture & life science
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• v.46 no.4
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• pp.69-84
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• 2012

To provide the basic information on the excavation, conservation, and systematic management plan for preservation of valuable forested wetlands, a field survey was analyzed at public and private forests in Daegu city, 2010. The expected points of FGIS were identified, and buffer zones for the protection of forested wetlands were derived. According to the results from the 11 points of forested wetland, the flora of wetlands in Daegu city were consisted of a total of 169 taxa; 63 families, 131 genera, 148 species, 2 subspecies, 14 varieties, and 5 forms. The species diversity of shrubs in forest wetlands was highest at 1.560, and the evenness was highest in shrub trees at 0.913. Considering the type of wetland, topography, etc., the buffer zone was set at 20~50m from the core area boundary.

• The Journal of the Acoustical Society of Korea
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• v.41 no.6
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• pp.669-679
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• 2022

Lithium-ion battery has been used for lots of electronic devices. With the popularization of batteries, researchers have focused on batteries' electrochemical performances by environmental conditions, such as temperature, vibration, shock and charging state. Meanwhile, due to very serious global warming, car companies have started using lithium-ion batteries even in cars, replacing internal combustion engines. However, batteries have been developed based on non-moving systems which is totally different from vehicles. In the line of the differences, researchers have tried to reveal relationship between variables from dynamic systems and batteries. In this review, we discuss the comprehensive effect of vibration and shock on batteries. We firstly summarize vibration profiles and effect of normal vibration on batteries. We also sum up effect of shock and penetration on batteries and introduce how ultrasound influences on batteries. Lastly, outlook for the battery design as well as dynamic design of EVs are discussed.

• Applied Chemistry for Engineering
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• v.4 no.3
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• pp.488-496
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• 1993

Natural zeolites have recently been the subject of intensive research due to their versatilities in possible industrial applications. Among several different types of domestic natural zeolites, clinoptilolite, is one of the highly prospective domestic natural zeolites. However, it is always possible for heulandite, the isostructure of clinoptilolite, to coexist with clinoptilolite. Unfortunately, heulandite is thermally very unstable restricting its application to industrial process. In this paper, the effects of ion exchanges and heat-treatments on the thermal stability for domestic natural zeolite, heulandite are described. Two different ion-exchanging experiments were carried out followed by heat-treatments at different temperatures. X-ray, IR and AA spectroscopic analyses showed the enhancements in thermal stabilities of heulandite by $Na^+$ cation exchanges.