• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2022.10a
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• pp.585-587
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• 2022

The visual motivation between AP devices is NTP-based visual motivation through the access of the Internet through the internal wired LAN, but this has several seconds of visual difference in hundreds of milliseconds (msec) depending on the network. The frame for the output of the video will vary depending on the application, but usually 24 (image) frames are output to the screen in one second. Therefore, the visual synchronization between peripheral devices can be performed through the adjacent moving camera device, not the wired method. The programming method of generating API for synchronization command when creating an application for visual synchronization and delivering it to AP through MAC may differ from the time in synchronization command according to the environment of the operating system at the transmission side and the situation of the buffer queue of the MAC. Therefore, as a method to solve this problem, the renewal of visual information in the device driver terminal controlling MAC can be much more effective.

• Journal of Pharmaceutical Investigation
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• v.39 no.1
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• pp.73-78
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• 2009

A simple LC-MS/MS method of rabeprazole in human plasma was developed and validated. Rabeprazole and Internal standard (I.S), omeprazole, were extracted from human plasma by liquid liquid extraction, chromatographic separation of rabaprazole in plasma was achieved at $45^{\circ}C$ with a Shiseido UG120 $C_{18}$ column and methanol-10 mM ammonium acetate buffer (pH 9.42 with ammonium water), as mobile phase. Rabeprazole produced a protonated precursor ion [$(M+H)^+$] at m/z 360.10 and corresponding product ion at m/z 242.21. Internal standard produced a protonated precursor ion [$(M+H)^+$] at 346.09 and corresponding product ion at m/z 198.09. This method showed linear response over the concentration range of $1{\sim}500\;ng/mL$ with correalation coefficient greater than 0.99. The lower limit of quantitation (LLOQ) using 0.2 mL plasma was 1 ng/mL, which was sensitive enough for pharmacokinetics studies. The method was specific and validated with a limit of quantitation of 1 ng/mL. The intra-day and inter-day precision and accuracy were acceptable for all samples including the LLOQ. The applicability of the method was demonstrated by analysis of plasma after administration of a single 10 mg dose to 36 healthy subject. From the plasma rabeprazole concentration versus time curves, the mean $AUC_t$ (The area under the plasma concentration-time curve from time 0 to 12 hr ) was $691.36{\pm}321.88\;ng{\cdot}hr/mL$, $C_{max}$ (maximum plasma drug concentration) of $353.21{\pm}131.52\;ng/mL$ reached $3.4{\pm}1.1\;hr$ after adiministration. The mean biological half-life of rabeprazole was $1.37{\pm}0.75\;hr$. Based on the results, this simple method could readily be used in pharmacokinetics studies.

• Proceedings of the Korean Society of Toxicology Conference
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• 2006.11a
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• pp.65-74
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• 2006

Modem drug discovery requires rapid pharmacokinetic evaluation of chemically diverse compounds for early candidate selection. This demands the development of analytical methods that offer high-throughput of samples. Naturally, liquid chromatography / tandem mass spectrometry (LC-MS/MS) is choice of the analytical method because of its superior sensitivity and selectivity. As a result of the short analysis time(typically 3-5min) by LC-MS/MS, sample preparation has become the rate- determining step in the whole analytical cycle. Consequently tremendous efforts are being made to speed up and automate this step. In a typical automated 96-well SPE(solid-phase extraction) procedure, plasma samples are transferred to the 96-well SPE plate, internal standard and aqueous buffer solutions are added and then vacuum is applied using the robotic liquid handling system. It takes only 20-90 min to process 96 samples by automated SPE and the analyst is physically occupied for only approximately 10 min. Recently, the ultra-high flow rate liquid chromatography (turbulent-flow chromatography)has sparked a huge interest for rapid and direct quantitation of drugs in plasma. There is no sample preparation except for sample aliquotting, internal standard addition and centrifugation. This type of analysis is achieved by using a small diameter column with a large particle size(30-5O ${\mu}$m) and a high flow rate, typically between 3-5 ml/min. Silica-based monolithic HPLC columns contain a novel chromatographic support in which the traditional particulate packing has been replaced with a single, continuous network (monolith) of pcrous silica. The main advantage of such a network is decreased backpressure due to macropores (2 ${\mu}$m) throughout the network. This allows high flow rates, and hence fast analyses that are unattainable with traditional particulate columns. The reduction of particle diameter in HPLC results in increased column efficiency. use of small particles (<2 urn), however, requires p.essu.es beyond the traditional 6,000 psi of conventional pumping devices. Instrumental development in recent years has resulted in pumping devices capable of handling the requirements of columns packed with small particles. The staggered parallel HPLC system consists of four fully independent binary HPLC pumps, a modified auto sampler, and a series of switching and selector valves all controlled by a single computer program. The system improves sample throughput without sacrificing chromatographic separation or data quality. Sample throughput can be increased nearly four-fold without requiring significant changes in current analytical procedures. The process of Bioanalytical Method Validation is required by the FDA to assess and verify the performance of a chronlatographic method prior to its application in sample analysis. The validation should address the selectivity, linearity, accuracy, precision and stability of the method. This presentation will provide all overview of the work required to accomplish a full validation and show how a chromatographic method is suitable for toxirokinetic sample analysis. A liquid chromatography/tandem mass spectrometry (LC-MS/MS) method developed to quantitate drug levels in dog plasma will be used as an example of tile process.

• Journal of the Institute of Electronics and Information Engineers
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• v.50 no.11
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• pp.70-77
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• 2013

We suggest a low area and high efficiency switched-mode power supply (SMPS) with a pulse width modulation (PWM) generator based on a pseudo relaxation-oscillating technique. In the proposed circuit, the PWM duty ratio is determined by the voltage slope control of an internal capacitor according to amount of charging current in a PWM generator. Compared to conventional SMPSs, the proposed control method consists of a simple structure without the filter circuits needed for an analog-controlled SMPS or the digital compensator used by a digitally-controlled SMPS. The proposed circuit is able to operate at switching frequency of 1MHz~10MHz, as this frequency can be controlled from the selection of one of the internal capacitors in a PWM generator. The maximum current of the core circuit is 2.7 mA, and the total current of the entire circuit including output buffer driver is 15 mA at 10 MHz switching frequency. The proposed SMPS has a simulated maximum ripple voltage of 7mV. In this paper, to verify the operation of the proposed circuit, we performed simulation using Dongbu Hitek BCD $0.35{\mu}m$ technology and measured the proposed circuit.

• Journal of the Korean Electrochemical Society
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• v.27 no.1
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• pp.32-39
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• 2024

The key components of a Phosphoric acid fuel cell (PAFC) are an electrode catalyst, an electrolyte matrix and a gas diffusion layer (GDL). In this study, we introduced a microporous layer on the GDL of PAFC to enhance liquid electrolyte management and overall electrochemical performance of PAFC. MPL is primarily used in polymer electrolyte membrane fuel cells to serve as an intermediate buffer layer, effectively managing water within the electrode and reducing contact resistance. In this study, electrodes were fabricated using GDLs with and without MPL to examine the influence of MPL on the performance of PAFC. Internal resistance and polarization curves of the unit cell were measured and compared to each other to assess the impact of MPL on PAFC electrode performance. As the results, the application of MPL improved power density from 170.2 to 192.1 mW/cm². MPL effectively managed electrolyte and water within the matrix and electrode, enhancing stability. Furthermore, the application of MPL reduced internal resistance in the electrode, resulting in sustained and stable performance even during long-term operation.

• The Journal of the Korean Society for Microbiology
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• v.18 no.1
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• pp.73-85
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• 1983

The advantages of the enzyme-linked immunosorbent assay(ELISA) are its sensitivity and its simplicity in detecting IgM and IgG antibodies. For applying the ELISA to the diagnosis of typhoid fever, first of all, experiments were performed to determine which concentration of killed whole cell antigens and lipopolysaccharide(LPS) antigens of S. typhi(0.901 w) were optimally coated to the wells of the polystyrene and polyvinylchloride microplate, using the hyperimmune sera from rabbits against S. typhi. By using both kinds of antigens of S. typhi adsorbed to the ELISA microplate, the changing patterns of IgG and IgM antibodies in the sera from rabbits responding to the killed whole cell antigens of S. typhi(0901 w) during the prolonged immunization were serially traced by the ELISA. At the same time, the level of antibodies against S. typhi in sera fron patients with typhoid fever and from normal healthy persons were measured by the ELISA employing the killed whole cell antigens and LPS antigens as the coating antigens. The results obtained were summerized as follow: 1. The optimal concentration of the killed whole cell antigens, which were more easily adsorbed to the polystyrene plate than the polyvinylchloride plate, was $10^8cells/ml$ of carbonate buffer(pH. 9.6) on the wells of the polystyrene plate when treated at $37^{\circ}C$ for 4 hours. On the other hand, the optimal concentration of lipopolysaccharide antigens, which were adsorbed only to the polyvinylchloride plate, was $100{\mu}g/ml$ of carbonate buffer(pH. 9.6) on the wells of the polyvinylchloride plate when treated at $37^{\circ}C$ for 4 hours. 2. IgM antibody response were dominating in rabbits responding to the killed whole cell antigens of S. typhi(0.901 w), and were more specific to the LPS antigens than to the killed whole cell antigens in the ELISA. Good correlations were made between the IgM titers by the ELISA and the aggglutinating titers of sera from the immunized rabbits. 3. Both IgG and IgM agglutination titers by the ELISA in sera from most of patients with typhoid fever were above 1:320 but those in sera from most of normal, healthy persons were below 1:80. 4. There were close correlations between the antibody titers by the ELISA and the agglutinating titers to the killed whole cell antigens in the tested human sera, IgM titers being more correlated with the agglutinating titers than IgG titers. But a little correlations were made between the antibody titers by the ELISA and the agglutinating titers to the LPS antigens. 5. IgM titers in the tested human sera were similar to IgG titers detected by the ELISA employing the killd whole cells antigens and the LPS antigens. 6. Good correlations were made between the antibody titers demonstrated by the ELISA performed on the killed whole cell antigens and the LPS antigens as the different, coating antigens on the ELISA microplates.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.8C
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• pp.1113-1124
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• 2004

In this paper, we proposed a hardware(H/W) structure which can compress and recontruct the input image in real time operation and implemented it into a FPGA platform using VHDL(VHSIC Hardware Description Language). All the image processing element to process both compression and reconstruction in a FPGA were considered each of them was mapped into H/W with the efficient structure for FPGA. We used the DWT(discrete wavelet transform) which transforms the data from spatial domain to the frequency domain, because use considered the motion JPEG2000 as the application. The implemented H/W is separated to both the data path part and the control part. The data path part consisted of the image processing blocks and the data processing blocks. The image processing blocks consisted of the DWT Kernel fur the filtering by DWT, Quantizer/Huffman Encoder, Inverse Adder/Buffer for adding the low frequency coefficient to the high frequency one in the inverse DWT operation, and Huffman Decoder. Also there existed the interface blocks for communicating with the external application environments and the timing blocks for buffering between the internal blocks The global operations of the designed H/W are the image compression and the reconstruction, and it is operated by the unit of a field synchronized with the A/D converter. The implemented H/W used the 69%(16980) LAB(Logic Array Block) and 9%(28352) ESB(Embedded System Block) in the APEX20KC EP20K600CB652-7 FPGA chip of ALTERA, and stably operated in the 70MHz clock frequency. So we verified the real time operation of 60 fields/sec(30 frames/sec).

• The Journal of Dong Guk Oriental Medicine
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• v.7 no.2
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• pp.97-105
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• 1999

Hepatic tissues of ICR mouse were intraperitoneally injeced with Colpomenia bullosa(CB) Extract after Triton WR-1339(TX) injection were observed to investigate the antihyperlipermic effect of CB extract for hyperlipidemic hepatic tissue caused by destruction of lipid metabolism. The hepatic tissues were obtained at hour-24, 48, and 72 after TX injection with CB extract treatment. And then these specimen were fixed in 10% neutral buffer solution and were cryocut. The tissue stained by H&E for general morphology and sudan black B for lipid distribution. The increase of hepatocyte havinig meshlike cytoplasm were shown in all hepatic lobules after TX injection and the hepatic plates were disappeared in the region of meshlike hepatocyte aggregation. But the hepatocyte having meshlike cytoplasm were disappeared and hapatic plate were rearranged in CB extract injected mouse. The number of blue black colored lipid drop in hepatic cytoplasm of mouse injected with TX were increased and the size of lipid drop were enlarged. But the number of lipid drop in hepatic cytoplasm of mouse treated CB extract were decreased and the size of lipid drop were diminished. As results indicated that the accumulation of lipid drop caused by TX injection were mitigated by the antihyperlipidermic effect of CB extract.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.843-850
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• 2020

The purpose of this study is to evaluate the structural risk and weakness of a railway tank car through nonlinear collision analysis according to overseas collision safety standards. The goal is to propose a crash safety design guideline for railway tank cars for transporting dangerous goods in Korea. We analyzed the buffer impact test procedure of railway freight cars prescribed in EN 12663-2 and the tank puncture test criteria prescribed in 49CFR179. A nonlinear finite element model according to each standard was modeled using LS-DYNA, a commercial finite element analysis solver. As a result of the buffing impact test simulation, it was predicted that plastic deformation would not occur at a collision speed of 6 km/h or less. However, plastic deformation was detected at the rear of the center sill and at the tank center supporting the structure at a collision speed of 8 km/h or more. As a result of a head-on test simulation of tank puncture, the outer tank shell was destroyed at the corner of the tank head when 4% of the kinetic energy of the impacter was absorbed. The tank shell was destroyed in the area of contact with the impacter in the test mode analysis of tank shell puncture when the kinetic energy of the moving vehicle was reduced by 30%. Therefore, the simulation results of the puncture test show that fracture at the tank shell and leakage of the internal material is expected. Consequently, protection and structural design reinforcement are required on railway tank cars in Korea.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.1
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• pp.744-754
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• 2015

Buddhist temple construction at East Asia is considered one of the most important architecture activities together with the capital city and palace, where the pagoda is positioned at the center of a Buddhist temple as the most important element of Buddhist architecture enshrining Buddha's Sary. Accordingly, this study was performed to examine the procedure of how to build brick pagodas through the stone pagoda's internal structure between $7^{th}{\sim}9^{th}$ century while disassembling and repairing Andong Jotap-ri five-story brick pagoda. As a result, as the brick pagoda destruction phenomenon, there was a slip phenomenon by side forces, member's plastic temperature, and mixed material differences. Second, like a stone pagoda, brick pagoda is classified and constructed by the design and structural parts. According to the analysis, the design part is formed by the most edge brick, and the structure part places stone material at the buffer zone in the design brick from most edge brick and intra-center, i.e., at the space to support a side force while the top weight is vertically led. When building a brick pagoda, putting a wood pole at inside center plays the role as holding parts. In addition, the center axis is connected to the bottom of the steel pole hole, A steel pole hole has holes to safely settle down and decide the position. Because of them, the steel pole is self-loaded, which may be installed by wood rather than immovable steel.