• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.9
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• pp.694-701
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• 2002

In this paper, through the study on locations of structural transducers for active control of the radiated sound from the vibrating plate, the active structural acoustic control (ASAC) system is proposed. And, for the evaluation of the proposed location, the experiment of the active structural acoustic control is implemented using the multi-channel filtered-x LMS algorithm and an additional filter (Acoustic Prediction Filter) to estimate the radiated sound using the acceleration signals of the plate. The structural transducers are piezoceramic actuator (PZT) and accelerometer. PZT is used as an actuator to reduce the vibration and the radiated sound. To maximize the control performance, each PZT actuator is located at the position that has the largest control sensitivity of the plate bending moment in the direction of x and y coordinates and the optimal PZT location is validated experimentally. Also, to find the acoustic prediction filter accurately, two accelerometers are located at the positions that have the largest radiation efficiencies of the plate, and the proposed locations are validated by simulation using the Rayleigh integral. The multi-channel filtered-x LMS algorithm is introduced to control a complex 2-D structural vibration mode. Finding the locations of structural transducers for active structural acoustic control of the radiated sound, the active structural acoustic control (ASAC) system can be presented and validated by experiments using a real time control system.

• Journal of Korea Water Resources Association
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• v.34 no.4
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• pp.289-301
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• 2001

A fractional step finite difference model for the longitudinal dispersion of nonconservative pollutants is applied to the Nakdong River to simulate the phenol spill accident which occurred on March, 1971. Prior to the dispersion calculation, the flow conditions are simulated to provide inputs to the dispersion model. An unsteady flow model based on Preissmann's four-point scheme is used for this purpose. Sensitivities of the dispersion calculation to empirical equations for dispersion coefficient and to the first-order decay coefficient are analyzed. The time to peak concentration at a downstream location is significantly different depending on the formula for the dispersion coefficient. Although the decay coefficient does not affect the shape of the temporal concentration distribution, the concentration values depend on the decay coefficient verb significantly. An optimization technique is used to calibrate the dispersion model as well as the flow model. The time to the peak concentration is simulated for major positions of water intake along the Nakdong River.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.30 no.6_1
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• pp.511-518
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• 2012

It is well-known that non-metric digital cameras have to be calibrated for the close-range photogrammetry. But, the self-calibration is still not an easy task because it requires rather a large calibration site of accurate control points, multiple image acquisitions in different positions, and accurate image point measurements that are quite labor-intensive and time-consuming. Based on the premise, this study carried out check point accuracy analysis from self-calibration of different control point designs and photo combinations. The test results showed that the calibration using three photos covering three-dimensional control points produced high accuracy, but control points on a plane could attain the comparable accuracy with four photos including a 90-degree rotated photo. We then compared the target accuracy of on-site self-calibration using flat control points to that of laboratory-self calibration and observed comparable results.

• Molecules and Cells
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• v.23 no.2
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• pp.182-191
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• 2007

The complete mitochondrial genome of a troglobite millipede Antrokoreana gracilipes (Verhoeff, 1938) (Dipolopoda, Juliformia, Julida) was sequenced and characterized. The genome (14,747 bp) contains 37 genes (2 ribosomal RNA genes, 22 transfer RNA genes and 13 protein-encoding genes) and two large non-coding regions (225 bp and 31 bp), as previously reported for two diplopods, Narceus annularus (order Spirobolida) and Thyropygus sp. (order Spirostreptida). The A + T content of the genome is 62.1%, and four tRNAs ($tRNA^{Ser(AGN)}$, $tRNA^{Cys}$, $tRNA^{Ile}$ and $tRNA^{Met}$) have unusual and unstable secondary structures. Whereas Narceus and Thyropygus have identical gene arrangements, the $tRNA^{Thr}$ and $tRNA^{Trp}$ of Antrokoreana differ from them in their orientations and/or positions. This suggests that the Spirobolida and Spirostreptida are more closely related to each other than to the Dipolopoda. Three scenarios are proposed to account for the unique gene arrangement of Antrokoreana. The data also imply that the Duplication and Nonrandom Loss (DNL) model is applicable to the order Julida. Bayesian inference (BI) and maximum likelihood (ML) analyses using amino acid sequences deduced from the 12 mitochondrial protein-encoding genes (excluding ATP8) support the view that the three juliformian members are monophyletic (BI 100%; ML 100%), that Thyropygus (Spirostreptida) and Narceus (Spirobolida) are clustered together (BI 100%; ML 83%), and that Antrokoreana (Julida) is a sister of the two. However, due to conflict with previous reports using cladistic approaches based on morphological characteristics, further studies are needed to confirm the close relationship between Spirostreptida and Spirobolida.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.08a
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• pp.75-75
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• 2011

Recently, dye-sensitized solar cell (DSSC) attracts great attention as a promising alternative to conventional silicon solar cells. One of the key components for the DSSC would be the nanocrystalline TiO2 electrode, and the control of interface between TiO2 and TCO is a highly important issue in improving the photovoltaic conversion efficiency. In this work, we applied various interfacial layers, and analyzed their effect in enhancing photovoltaic properties. In overall, introduction of interfacial layers increased both the Voc and Jsc, since the back-reaction of electrons from TCO to electrolyte could be blocked. First, several metal oxides with different band gaps and positions were employed as interfacial layer. SnO2, TiO2, and ZrO2 nanoparticles in the size of 3-5 nm have been synthesized. Among them, the interfacial layer of SnO2, which has lower flat-band potential than that of TiO2, exhibited the best performance in increasing the photovoltaic efficiency of DSSC. Second, long-range ordered cubic mesoporous TiO2 films, prepared by using triblock copolymer-templated sol-gel method via evaporation-induced self-assembly (EISA) process, were utilized as an interfacial layer. Mesoporous TiO2 films seem to be one of the best interfacial layers, due to their additional effect, improving the adhesion to TCO and showing an anti-reflective effect. Third, we handled the issues related to the optimum thickness of interfacial layers. It was also found that in fabricating DSSC at low temperature, the role of interfacial layer turned out to be a lot more important. The self-assembled interfacial layer fabricated at room temperature leads to the efficient transport of photo-injected electrons from TiO2 to TCO, as well as blocking the back-reaction from TCO to I3-. As a result, fill factor (FF) was remarkably increased, as well as increase in Voc and Jsc.

• Journal of Microbiology
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• v.41 no.2
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• pp.129-136
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• 2003

The Epstein-Barr virus (EBV)-encoded latent membrane protein 1 (LMPI) exhibits considerable sequence heterogeneity among EBV isolates. Seven distinct EBV strains have been defined based on sequence polymorphisms in the LMPI gene, which are designated China 1, China 2, China 3, Alaskan, Mediterranean, NC, and the B95-8 strains. In this study, we analyzed a 30-bp deletion and sequence variations in the carboxy-terminal region of the LMPl gene in 12 EBV isolates from spontaneous lym-phoblastoid cell lines derived from individuals with non-EBV associated cancers in Korea. Eleven of the 12 isolates showed a 30-bp deletion spanning LMPI amino acids 342 to 353, suggesting a high prevalence of the LMPI 30-bp deletion variant among EBV isolates in Korea. In addition, all 12 isolates had a 15-bp common deletion in the 33-bp repeat region and multiple base-pair changes relative to the prototype B95-8 EBV strain along with variations in the number of the 33-bp repeats. The bp changes at positions 168746, 168694, 168687, 168395, 168357, 168355, 168631, 168320, 168308, 168295, and 168225 were highly conserved among the isolates. Comparative analysis of sequence change patterns in the LMPI carboxy-terminal coding region identified nine 30-bp deletion variants as China 1, two deletion variants as a possible interstrain between the Alaskan and China 1 strains, and a single undeleted variant as a possible variant of the Alaskan strain. These results suggest the predominance of the China 1 EBV strain in the Korean population.

• Journal of Biosystems Engineering
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• v.28 no.1
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• pp.65-76
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• 2003

The analysis of cow body parameters is important to provide some useful information fur cow management and cow evaluation. Present methods give many stresses to cows because they are invasive and constrain cow postures during measurement of body parameters. This study was conducted to develop the stereo vision system fur non-invasive analysis of cow body features. Body feature parameters of 16 heads at two farms(A, B) were measured using scales and nineteen stereo images of them with walking postures were captured under outdoor illumination. In this study, the camera calibration and inverse perspective transformation technique was established fer the stereo vision system. Two calibration results were presented for farm A and fm B, respectively because setup distances from camera to cow were 510 cm at farm A and 630cm at farm B. Calibration error values fer the stereo vision system were within 2 cm for farm A and less than 4.9 cm for farm B. Eleven feature points of cow body were extracted on stereo images interactively and five assistant points were determined by computer program. 3D world coordinates for these 15 points were calculated by computer program and also used for calculation of cow body parameters such as withers height. pelvic arch height. body length. slope body length. chest depth and chest width. Measured errors for body parameters were less than 10% for most cows. For a few cow. measured errors for slope body length and chest width were more than 10% due to searching errors fer their feature points at inside-body positions. Equation for chest girth estimated by chest depth and chest width was presented. Maximum of estimated error fur chest girth was within 10% of real values and mean value of estimated error was 8.2cm. The analysis of cow body parameters using stereo vision system were successful although body shape on the binocular stereo image was distorted due to cow movements.

• Journal of Biosystems Engineering
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• v.38 no.2
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• pp.81-86
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• 2013

Purpose: Recently, domestic and abroad consumption of mushroom has been increasing. Especially, oyster mushroom has been the most consumed product, sharing one third of the mushroom market. The air temperature differences between relative positions of the mushroom farms were needs to be minimal. However, in reality, the air temperature differences ranged from 2 to $5^{\circ}C$. Because of this, the mushrooms are non-uniform growth as well as decrease in both quality and quantity. Although air circulators have been employed by oyster mushroom farms to minimize air temperature differences, no experiments have been performed to illustrate the effect of the air circulators. Methods: This experiment is designed to analyze the effect of the air circulation by constructing a prototype air circulator and measuring the air temperature when the circulator was position at different heights (50 cm, 150 cm, 200 cm) from the floor in the center. Result: The horizontal plane air temperature of the first growing bed when the air circulator was installed 50cm above the floor in the center, once not using the air circulators and the other time using the air circulators, yielded the air temperature differences of $8.6^{\circ}C$ and $1.8^{\circ}C$ and deviations of 2.82 and 0.60, respectively. The third growing bed's air temperature differences were $10.0^{\circ}C$, $1.6^{\circ}C$ and deviations 3.28, 0.64, each respectively. These outcomes proved that the use of air circulators minimized the air temperature difference and deviation. The use of air circulators helped minimize the air temperature differences and the derivations in oyster mushroom farm. Conclusion: The use of air circulators helped balance the air temperature distribution in oyster mushroom farm.

• Analytical Science and Technology
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• v.18 no.4
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• pp.278-286
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• 2005

The crystal structure of ($Tl_{71}$-Y ($Tl_{71}Si_{121}Al_{71}O_{384}$), ${\alpha}=24.706(3){\AA}$, dehydrated at 653 K and $8{\times}10^{-6}$ torr, has been determined by single-crystal X-ray diffraction techniques in the cubic space group $Fd\bar{3}m$ at 294(1) K. The structure was refined using all intensities to the final error indices (using only the 302 reflection for which $F_{\circ}$ > $4{\sigma}(F_0)$) $R_1=0.0602$ (based on F) and $R_w=0.1744$ (based on $F_2$). The 71 $Tl^+$ ions per unit cell are found at four crystallographically distinct positions. Site I' position in the sodalite cavity opposite D6Rs are each occupied by eighteen $Tl^+$ ions per unit cell; these $Tl^+$ ions are recessed ca. $1.45{\AA}$ into the sodalite cavity from their O(3) plane (Tl-O=2.701(15), $3.163(16){\AA}$ and O-Tl-O=$92.1(4)^{\circ}$). The 23 $T1^+$ ions fill site II in the supercage; these $T1^+$ ions are recessed ca. $1.58{\AA}$ into the supercage from their O(2) plane (Tl-O = 2.850(16), $3.156(16){\AA}$ and O-T1-O = $85.1(5)^{\circ}$). The 19 $Tl^+$ ions lie at site III' in the supercage near a triple 4-ring (Tl-O = 3.10(7), $3.39(5){\AA}$ and O-Tl-O = 47.8(9), $95.3(18)^{\circ}$) and the remaining II ions occupy another site III' near a triple 4-ring in the supercage (Tl-O = 2.81(4), $2.71(4){\AA}$ and O-Tl-O = $57.3(8)^{\circ}$).

• Journal of Broadcast Engineering
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• v.7 no.1
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• pp.21-27
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• 2002

This paper presents a mews event reenactment system (NERS), which generates virtual character animations in a quick and convenient manner. Thus, NERS can be used to produce computer graphics(CG) scenes of news events that are hard to photograph, such as fire, traffic accident, cases of murder, and so on. By using plenty of captured motion data and CG model data this system produces an appropriate animation of virtual characters straightforwardly without any motion capturing device and actors in the authoring stage. NERS is designed to be capable of making virtual characters move along user-defined paths, stitching motions smoothly and modifyingthe positions and of the articulations of a virtual character in a specific frame. Therefore a virtual character can be controlled precisely so as to interact with the virtual environments and other characters. NERS provides both an interactive and script-based (MEL: Maya Embedded Language) interface so that user can this system in a convenient way. This system has been implemented as a plug-in of commercial CG tool, Maya (Alias/wavefront), in order to make use of its advanced functions