• Journal of the Korean Chemical Society
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• v.56 no.1
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• pp.62-67
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• 2012

A series of homo binuclear complexs of the type $[M_2(L/L^')(NO_3)n].mH_2O$, [where $M=U{O_2}^{2+},\;Th^{4+},\;ZrO^{2+}$] and $[(VO)_2(L/L^')(SO_4)_2]{\cdot}2H_2O$, L=1,5,6,9,12,15,16,20 octaaza-7,813,14-tetraphenyl-2,4,17,19-tetramethyl-1,4,6,8,12,14,16,19-docosaoctene (OTTDO) or L'=10:11;21:22-dibenzo-1,5,6,9,12,15,16,20-octaaza-7,813,14-tetraphenyl-2,4,17,19-tetramethyl-1,4,6,8,12,14,16,19-docosaoctene (DOTTOT), n=4 for $U{O_2}^{2+}$, $ZrO^{2+}$ n=8 for $Th^{4+}$ m=1,2,3 respectively, have been synthesized in template method from ethylenediamine/orthophenylene diamine, benzil monohydrazone and acetyl acetone and characterized on the basis of elemental analysis, thermal analysis, molar conductivity, magnetic moment, electronic, infrared, $^1H$-NMR studies. The results indicate that the VO(IV) ion is penta co-ordinated yielding paramagnetic complexes; $UO_2(VI)$, ZrO(IV) ions are hexa co-ordinated where as Th(IV) ion is octa co-ordinated yielding diamagnetic complexes of above composition. The fungi toxicity of the ZrO(IV) and VO(IV) complexes against some fungal pathogen has been studied.

• Journal of Microbiology and Biotechnology
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• v.20 no.6
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• pp.1018-1021
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• 2010

Metallic and non-metallic isomerases can be used to produce commercially important monosaccharides. To determine which category of isomerase is more suitable as a template for directed evolution to improve enzymes for galactose isomerization, L-arabinose isomerase from Escherichia coli (ECAI; E.C. 5.3.1.4) and tagatose-6-phosphate isomerase from Staphylococcus aureus (SATI; E.C. 5.3.1.26) were chosen as models of a metallic and non-metallic isomerase, respectively. Random mutations were introduced into the genes encoding ECAI and SATI at the same rate, resulting in the generation of 515 mutants of each isomerase. The isomerization activity of each of the mutants toward a non-natural substrate (galactose) was then measured. With an average mutation rate of 0.2 mutations/kb, 47.5% of the mutated ECAIs showed an increase in activity compared with wild-type ECAI, and the remaining 52.5% showed a decrease in activity. Among the mutated SATIs, 58.6% showed an increase in activity, whereas 41.4% showed a decrease in activity. Mutant clones showing a significant change in relative activity were sequenced and specific increases in activity were measured. The maximum increase in activity achieved by mutation of ECAI was 130%, and that for SATI was 190%. Based on these results, the characteristics of the different isomerases are discussed in terms of their usefulness for directed evolution of non-natural substrate isomerization.

• Journal of Sensor Science and Technology
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• v.18 no.2
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• pp.110-115
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• 2009

Polystyrene (PS) microspheres were used to good advantage as a template material to prepare macroporous $TiO_2$ thin films. This is enabled to run the thermal decomposition of the PS without the collapsing of the 3-D macroporous framework during the calcination step. $TiO_2$ thin films were deposited onto the colloidal templated substrates at room temperature by RF sputtering, and then samples were thermally treated at $450^{\circ}C$ for 40.min in air to remove the organic colloidal template and induce crystallization of the $TiO_2$ film. The macroporous $TiO_2$ thin film exhibited a quasi-ordered partially hexagonal close-packed structure. Burst holes, estimated to be formed during PS thermal decomposition, are seen as the hemisphere walls. the inner as well as the outer surfaces of the hollow hemispheres formed by the method of thermal decomposition can be easily accessed by the diffusing gas species. As a consequence, the active surface area interacting with the gas species is expected to be enlarged about by a factor of fourth as large as compared to that of a planar films. Also the thickness at neighboring hemisphere could be controlled a few nm thickness. If the acceptor density becomes as large that depletion width reaches those thickness, the device is in the pinch off-situation and a strong resistance change should be observed.

• Journal of Korea Multimedia Society
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• v.8 no.3
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• pp.389-397
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• 2005

In this paper, we study the synchronization method of animated simulations and VRs for on-line virtual reality education system. To build the data of animated simulations and synchronization modules of VRML content, the media-synchronizing technology, HTML + TIME and scripts are used. The VRML control module ismade into Java applet using the Java EAI provided for the web and the interface for VRML contents. To control the animation of VRML contents, the node information is extracted, and an animation production template capable of controlling animation in inter-connection with VRML content is made. With evaluation of the animation control performance, processing speed, synchronization performance between media in the system built, more improved results are obtained. We would like to suggest a education system with easy system construction and various multi-medium applicability by realizing HTML + TIME media synchronization and VRML web 3D virtual reality creation techniques, and animated images and 3D animation controls according to time using Java through this study.

• Journal of Korean Society for Geospatial Information Science
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• v.12 no.4 s.31
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• pp.61-68
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• 2004

In this paper, we suggest an automatic technique to obtain 3-D road information in complex urban areas using road pavement markings. This method is composed of following three main steps. The first step is extracting the pavement markings from aerial images, the second one is matching the same pavement markings in two aerial images, and the last one is obtaining the 3-D coordinates of those using EOP(exterior orientation parameters) of aerial images. Here, we focus on the first and second step because the last step can be performed by using the well hewn collinearity condition equation. We used geometric properties and spatial relationships of the pavement markings to extract the lane line markings on the images and extracted arrow lane markings additionally using template matching. And then, we obtained 3-D coordinates of the road using relational matching for the pavement markings. In order to evaluate the accuracy of extraction, we did a visual inspection and compared the result of this technique with those measured by digital photogrammetric system.

• Journal of Animal Science and Technology
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• v.47 no.3
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• pp.317-324
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• 2005

A method for sex determination of pigs was examined using polymerase chain reaction(PCR). Sex determining region Y(SRY) gene encoded on Y chromosome plays a key role for primary male development. Zinc finger X-Y(ZFX-ZFY) gene, one of the X-V homology gene group was found on the X and Y chromosomes, respectively, We tested for molecular sexing by amplification patterns of SRY and ZF genes. Genomic DNAs from various resources including porcine hairs and semen collected from domestic pig breeds and native pigs was used for PCR assay of each gene. The amplified products for porcine SRY gene were yielded only in males but not in females. On the other hand, two differential patterns were observed in amplification of ZF gene reflecting the chromosomal dimorphism by a length polymorphism between X and Y chromosomes. Of both, a common band was detected in all individuals tested so that this band might be amplified from ZFX gene as a PCR template, but another is specific for males indicated that from ZFY. The result of PCR assay provides identical information to that from investigation of phenotypic genders of the pigs tested. We suggest that this PCR strategy to determine porcine sexes using comparison of the amplification patterns of the SRY gene specific for Y chromosome and the dimorphic ZF gene between X and Y chromosomes may be a rapid and precise method for discrimination of two sexes and applied to DNA analysis of small samples such as embryonic blastomere, semen, and hairs.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.41 no.8
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• pp.737-744
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• 2017

A new ultralow density material (ULDM) named Shellular was recently introduced. Shellular has a periodic cellular structure with smooth-curved shells. The template for the first Shellular was fabricated using lithography and its shape was similar to the P-surface, a type of triply periodic minimal surface (TPMS). In this paper, a new fabrication method of Shellular with D-surface, named W-Shellular, is described. W-Shellular is fabricated based on weaving of polymer wires. The compressive properties are evaluated by experiments and analysis in comparison with the previous ULDMs.

• Journal of Sensor Science and Technology
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• v.30 no.6
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• pp.376-380
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• 2021

The accurate detection of hydrogen gas molecules is considered to be important for industrial safety. However, the selective detection of the gas using semiconductive metal oxides (SMOs)-based sensors is challenging. Here, we describe the fabrication of H₂ sensors in which a nanocellulose/graphene oxide (GO) hybrid membrane is attached to SnO₂ nanosheets (NSs). One-dimensional (1D) nanocellulose fibrils are attached to the surface of GO NSs (GONC membrane) by mixing GO and nanocellulose in a solution. The as-prepared GONC membrane is employed as a sacrificial template for SnO₂ NSs as well as a molecular sieving membrane for selective H₂ filtration. The combination of GONC membrane and SnO₂ NSs showed substantial selectivity to hydrogen gas (R_air / R_gas > 10 @ 0.8 % H₂, 100 ℃) with noise level responses to interfering gases (H₂S, CO, CH₃COCH₃, C₂H₅OH, and NO₂). These remarkable sensing results are attributed mainly to the molecular sieving effect of the GONC membrane. These results can facilitate the development of a highly selective H₂ detector using SMO sensors.

• Journal of Powder Materials
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• v.28 no.2
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• pp.127-133
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• 2021

One-dimensional (1D) piezoelectric nanostructures are attractive candidates for energy generation because of their excellent piezoelectric properties attributed to their high aspect ratios and large surface areas. Vertically grown BaTiO₃ nanotube (NT) arrays on conducting substrates are intensively studied because they can be easily synthesized with excellent uniformity and anisotropic orientation. In this study, we demonstrate the synthesis of 1D BaTiO₃ NT arrays on a conductive Ti substrate by electrochemical anodization and sequential hydrothermal reactions. Subsequently, we explore the effect of hydrothermal reaction conditions on the piezoelectric energy conversion efficiency of the BaTiO₃ NT arrays. Vertically aligned TiO₂ NT arrays, which act as the initial template, are converted into BaTiO₃ NT arrays using hydrothermal reaction with various concentrations of the Ba source and reaction times. To validate the electrical output performance of the BaTiO₃ NT arrays, we measure the electricity generated from each NT array packaged with a conductive metal foil and epoxy under mechanical pushings. The generated output voltage signals from the BaTiO₃ NT arrays increase with increasing concentration of the Ba source and reaction time. These results provide a new strategy for fabricating advanced 1D piezoelectric nanostructures by demonstrating the correlation between hydrothermal reaction conditions and piezoelectric output performance.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.10
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• pp.5169-5175
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• 2013

We present a framework for 3D hand gesture design and modeling. We adapted two different pattern matching techniques, Dynamic Time Warping (DTW) and Hidden Markov Models (HMMs), to support the registration and evaluation of 3D hand gestures as well as their recognition. One key ingredient of our framework is a concept for the convenient gesture design and registration using HMMs. DTW is used to recognize hand gestures with a limited training data, and evaluate how the performed gesture is similar to its template gesture. We facilitate the use of visual sensors and body sensors for capturing both locative and inertial gesture information. In our experimental evaluation, we designed 18 example hand gestures and analyzed the performance of recognition methods and gesture features under various conditions. We discuss the variability between users in gesture performance.