• The Korean Journal of Applied Statistics
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• v.5 no.2
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• pp.193-209
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• 1992

We consider a Step Life Testing which is deviced for a two-component serial system with the considerably long life time. In the modelling stage we discuss the bivariate exponential distribution suggested by Block and Basu as the bivariate survival function for the two-component system, and develope the cumulative exposure model introduced by Nelson so that it can be used under the bivariate function. We consider inference on the component life time when the components are at work in the system by combining the information from system life test and that from the component tests carried out separately under the controlled environment. In data analysis, maximum likelihood estimators are discussed with the initial value obtained by an weighted least square method. Finally we discuss the optimal time for changing the stress in the simple step stress life testing.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.2
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• pp.61-69
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• 2003

In this paper, we developed the U parameter test system which inspects the property of DC parameter for semiconductor products. The developed system is interfaced by IBM-PC. It is consisted of CPLD part, ADC (Analogue to Digital Converter), DAC (Digital to Analogue Converter), voltage/current source, variable resistor and measurement part. In the proposed system, we have designed the constant voltage source and the constant current source in a part. The CPLD part is designed by VHBL, which it generates the control and converts the serial data to parallel data. The proposed system has two test channels and it operates VFCS mode and CFVS mode. The range of test voltage is from 0[V] to 100[V], and the range of test current is from 0[mA] to 100[mA)]. The diode is tested. The test results have a good performance.

• Journal of Korean Medicine Rehabilitation
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• v.33 no.1
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• pp.77-85
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• 2023

Objectives This study is designed to evaluate the safety of palmul-tang soft extract in healthy male volunteers. Methods Twelve healthy male volunteers were recruited. And this study was conducted in a single center. As a result of the laboratory test, the safety was evaluated by collecting vital signs of volunteers. Twelve subjects were assigned by serial number according to the registration order. For safety evaluation, blood samples were collected and vital signs were checked four times throughout the test period, including screening, pre-administration, post-administration (after 48 hours) and post-administration (after 7 days). The difference in variables was summarized as the mean±standard deviation. The normality was performed using Kolmogorov-Smirnov and Shapiro-Wilk test. If normality is satisfied, a paired t-test is applied. Otherwise, the Wilcoxon sign rank test, which is a nonparametric method, is applied. The significance was p<0.05. The incidence of all side effects is expressed as a percentage. Results In the case of red blood cell, hemoglobin, and hematocrit values, the result of normality test of variables for the difference value before and after administration is significant level p<0.05. However, all laboratory test values before and after administration did not deviate from the normal range. Also the deviations in the normal range could not be seen as significance related to this clinical trial. And no side effects related to clinical trial drugs were observed. Conclusions The soft extract of palmul-tang was considered safe for healthy male volunteers.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.12
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• pp.1923-1930
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• 2004

This paper presents digital microflow controllers(DMFC), where a fluidic digital-to-analog converter(DAC) is used to achieve high-linearity, fine-level flow control for applications to precision biomedical dosing systems. The fluidic DAC, composed of binary-weighted flow resistance, controls the flow-rate based on the ratio of the flow resistance to achieve high-precision flow-rate control. The binary-weighted flow resistance has been specified by a serial or a parallel connection of an identical flow resistor to improve the linearity of the flow-rate control, thereby making the flow-resistance ratio insensitive to the size uncertainty in flow resistors due to micromachining errors. We have designed and fabricated three different types of 4-digit DMFC: Prototype S and P are composed of the serial and the parallel combinations of an identical flow resistor, while Prototype V is based on the width-varied flow resistors. In the experimental study, we perform a static test for DMFC at the forward and backward flow conditions as well as a dynamic tests at pulsating flow conditions. The fabricated DMFC shows the nonlinearity of 5.0% and the flow-rate levels of 16(2$^{N}$) for the digital control of 4(N) valves. Among the 4-digit DMFC fabricated with micromachining errors, Prototypes S and P show 27.2% and 27.6% of the flow-rate deviation measured from Prototype V, respectively; thus verifying that Prototypes S and P are less sensitive to the micromachining error than Prototype V.V.

• Korean journal of applied entomology
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• v.18 no.2 s.39
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• pp.73-76
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• 1979

Two different isolates of Xanthomonas oryzae, KB 7785 of pathotype I and JN 7721 of pathotype III, that had been the most virulent isolates in the previous inoculation test, were reisolated from cultivar 'Milyang 23' and serially transferred to 10 times. They were inoculated to the 3 cultivars; 'Milyang 23' in Kinmaze group, 'Yushin' in Kogyoku group and 'Tongil' in Rantai-emas group cultivars. It was observed that the virulence of the isolate JN 7721 was more attenuated by the serial transfer on the Wakimoto's agar than the isolate KB 7785. The attenuation of virulence of the isolate JN 7721 was more significant at the cultivar 'Milyang23' than at the other cultivars. This suggests that the host-pathogen interactions and differences of the pathogenicity-maintenance ability among the pathogenic strains may be involved.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.46 no.1
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• pp.7-14
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• 2009

Lately, NAND flash cards have been used to store massive amounts of multimedia data. However, these nand flash cells itself has a slow operation time and by that, the nand flash cards are not appropriate for high performance massive data transfer. Indeed, most flash card products have a disadvantage in that they require plenty of time to transfer massive amounts of data. Therefore, we propose a new architectural design for the hardware and software of the NAND flash cards by improving their data transfer rate. Our design is based on a multiprocessing which is different from the conventional serial processing method. We simulated our design under the VIP (Virtual IP) environment, and verified our work using FPGA test platforms. As a result, the downloading performances was approximately 160MB/s on VIP and 85.3MB/s on FPGA.

• The Korean Journal of Malacology
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• v.27 no.4
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• pp.387-393
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• 2011

The objective of this study was to develop a real-time PCR method for the rapid detection and quantification of the protozoan pathogen Perkinsus olseni using a TaqMan probe. For the standard, genomic DNA was extracted from $10^5$ in vitro-cultured P. olseni trophozoites, and then 10-fold serial dilutions to the level of a single cell were prepared. To test the reliability of the technique, triplicates of genomic DNA were extracted from $5{\times}10^4$ cells and 10-fold serial dilutions to the level of 5 cells were prepared. The standards and samples were analyzed in duplicate using an $Exicycler^{TM}$ 96 real-time quantitative thermal block. For quantification, the threshold cycle ($C_T$) values of samples were compared with those obtained from standard dilutions. There was a strong linear relationship between the $C_T$ value and the log concentration of cells in the standard ($r^2$ = 0.996). Detection of DNA at a concentration as low as the equivalent of a single cell showed that the assay was sensitive enough to detect a single cell of P. olseni. The estimated number of P. olseni cells was similar to the original cell concentrations, indicating the reliability of P. olseni quantification by real-time PCR. Accordingly, the designed primers and probe may be used for the rapid detection and quantification of P. olseni from clam tissue, environmental water, and sediment samples.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.32 no.11C
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• pp.1102-1110
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• 2007

In this paper, we design the FPGA (Field-Programmable Gate Array) of the CAMB (Constant-Amplitude Multi-code Biorthogonal) modulation, and implement the SoC (System on Chip). The ASIC (Application Specific Integrated Circuit) chip is be implemented through targeting and board test. This 12Mbps modem SoC includes the ARM (Advanced RISC Machine)7TDMI, 64Kbyte SRAM(Static Random Access Memory) and ADC (Analog to Digital Converter)/DAC (Digital to Analog Converter) for flexible applications. Additionally, the modem SoC can support the variable communication interfaces such as the 16-bits PCMCIA (Personal Computer Memory Card International Association), USB (Universal Serial Bus) 1.1, and 16C550 Compatible UART (Universal Asynchronous Receiver/Transmitter).

• The Journal of Advanced Prosthodontics
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• v.10 no.3
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• pp.252-258
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• 2018

PURPOSE. The purpose of this study was to evaluate the repeatability and matching accuracy between two identical intraoral spectrophotometers. MATERIALS AND METHODS. The maxillary right central incisor, canine, and mandibular left central incisor of each of 30 patients were measured using 2 identical intraoral spectrophotometers with different serial numbers (EasyShade V). The color of each shade tab from 3 shade guides (VITA 3D-Master) was also determined with both devices. All measurements were performed by a single operator. Statistical analyses were performed to verify the repeatability, accuracy, and the differences between the devices with paired t-tests, one-way ANOVA, and intra-class correlation coefficients (ICCs) (${\alpha}=.05$). RESULTS. A high level of measurement repeatability (ICC>0.90) among $L^*$, $a^*$, and $b^*$ color components was observed within and between devices (P<.001). Intra-device matching agreement rates were 80.00% and 81.11%, respectively, while inter-device matching agreement rate was 51.85%. ANOVA revealed no significant different color values within each device, while paired t-test provided significant different color values between both devices. The CIEDE2000 color differences between both devices were $2.28{\pm}1.61$ ${\Delta}E_{00}$ for in-vivo readings. Regarding the clinical matching accuracy of both devices, ${\Delta}E_{00}$ values between teeth and matching shade tabs were $3.05{\pm}1.19$ and $2.86{\pm}1.02$, respectively. CONCLUSION. Although two EasyShade V devices with different serial numbers show high repeatability of CIE $L^*$, $a^*$, and $b^*$ measurements, they could provide different color values and shade for the same tooth.

• Korean Journal of Veterinary Service
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• v.22 no.2
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• pp.129-134
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• 1999

A preservation test of Toxoplasma gondii tachyzoites for considerable time was tried to obtain simple and economical methods using various suspending media at $4^{\circ}C$ rather than serial passage of the parasite in mice. The preservation period was a term that the tachyzoites were detected from the peritoneal fluid of mice after inoculation of 2$\times$$10^5$ organisms preserved according to the lapse of time. The numbers of tachyzoite per 1\textrm{mm}^3$ of the peritoneal fluid with 2$m\ell$ of the saline solution taken in 4days after inoculation were presented as percentage in proportion to the control. The numbers. of tachyzoite per 1\textrm{mm}^3$ of the peritoneal fluid of the control were consisted of the average number of the tachyzoites of 10 mice inoculated with 2$\times$$10^5$ organisms by serial mouse passage. The tachyzoites could be preserved for 26 days in the suspending medium of saline solution at $4^{\circ}C$ Ringer's solution for 18 days, Hank's solution for 28 days, and egg-glycerine solution for 50 days.