• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.190-195
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• 2000

The electrical properties and stability of ZPCE varistors consisted of $ZnO-Pr_6O_{11}-CoO-Er_2O_3$ ceramics were investigated. $ZnO-Pr_6O_{11}-CoO-Er_2O_3$ based ceramics were sintered at $1300^{\circ}C$ and $1350^{\circ}C$, respectively, without and with 0.5 mol% $Er_2O_3$. The varistors sintered at $1300^{\circ}C$ exhibited a better nonlinearity than that $1350^{\circ}C$. The varistors with $Er_2O_3$ of 0.5 mol% exhibited a high nonlinear exponent of 52.8. However, they easily degraded due to the low density below 85% of TD. On the other hand, the varistors sintered at $1350^{\circ}C$ without $Er_2O_3$ exhibited an extremely poor nonlinearity, but the varistors with $Er_2O_3$ of 0.5 mol% exhibited a relatively good nonlinearity, which the nonlinear exponent is 34.8 and the leakage current is $7.4\;{\mu}A$ Morever, they exhibited a very high stability, which the variation rate of varistor voltage, nonlinear exponent, and leakage current are -0.9%, -2.9%, and +2.7%, respectively, under the third stress $(0.80 V_{1mA}/90^{\circ}C/12h)$ + $(0.85 V_{1mA}/115^{\circ}C/12h)$ + $(0.90 V_{1mA}/120^{\circ}C/12h)$. Consequently, it was estimated that $ZnO-Pr_6O_{11}-CoO-Er_2O_3$ ceramics will be usefully applied to develop the advanced $Pr_6O_{11}$-based ZnO varistors.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.22
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• pp.9853-9857
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• 2014

Background: The morbidity and mortality rate of liver cancer continues to rise in China and advanced cases respond poorly to chemotherapy. Ribosomal protein L24 has been reported to be a potential therapeutic target whose depletion or acetylation inhibits polysome assembly and cell growth of cancer. Materials and Methods: Total RNA of cultured amycin-resistant and susceptible HepG2 cells was isolated, and real time quantitative RT-PCR were used to indicate differences between amycin-resistant and susceptible strains of HepG2 cells. Viability assays were used to determine amycin resistance in RPL24 transfected and control vector and null-transfected HepG2 cell lines. Results: The ribosomal protein L24 transcription level was 7.7 times higher in the drug-resistant HepG2 cells as compared to susceptible cells on quantitative RT-PCR analysis. This was associated with enhanced drug resistance as determined by methyl tritiated thymidine (3H-TdR) incorporation. Conclusions: The ribosomal protein L24 gene may have effects on drug resistance mechanisms in hepatocellular carcinoma HepG2 cells.

• International Journal of Control, Automation, and Systems
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• v.3 no.spc2
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• pp.296-301
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• 2005

As a new control strategy, the Nonlinear PID (NLPID) controller has been introduced successfully in power systems. The controller is free of planting model groundwork during the design procedure and is therefore able to be achieved quite simply. In this paper, a nonlinear PID controller used for a superconducting magnetic energy storage (SMES) unit connected to a power system is proposed. The purpose of designing such a controller is to improve the stability of the power system in a relatively wide operation range. The design procedure takes into account the active and reactive power cooperative control scheme as well as the simple structure so as to be more apt to practical utilization. Simulation is carried out to investigate the performance of the proposed controller in a high order nonlinear power system model under the. MATLAB environment. The results show satisfactory performance and good robustness of the controller. The feasibility of the controller is testified as well.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.05b
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• pp.103-107
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• 2000

The relationships between driving voltage and the wall charge distribution in the address period of surface discharge type AC Plasma Display Panel have been investigated. The quantity of wall charge on each electrode are detected simultaneously from the electrode current after applying only one addressing discharge pulse. The wall charge Qy on the scan electrode Y is nearly the sum of Qx on the address electrode X and Qz on the sustain electrode Z. The Qy increased with the driving voltage regardless of the kind of electrode, whereas the address time Td decreased, Qz and Qy are increased considerably with the blocking voltage Vz, whereas Qx is decreased. The increase rate of Qx, Qy and Qz for increase in Vz was $-13{\times}10^{-2}$ (pc/Vz), and $60{\times}10^{-2}$ (pc/Vz) and $70{\times}10^{-2}$(pc/Vz), respectively.

• Journal of the Korean Institute of Telematics and Electronics C
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• v.34C no.11
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• pp.66-75
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• 1997

We derive the system design parameters to implement the receiving system for the PCS mobile station to satisfy the J-sTD-018 which is the PCS mobile station(MS) minimum performance. Also we analyze the system performance and intermodulation spurious due to the values of a device cause the system performance degradation, is proposed. The simulation shows the receiver's maximum system noise figure to satisfy the receiver selectivity is approximately 11 dB. While the MS noise figure is 10dB with system margin 1 dB, the minimum selectivity is -71 dB at 1.25MHz frequency offset from the carrier frequency. And the input 3rd order intercept point of the MS class I and the MS class II~V is -9.5 dBm and -14dBm respectively. When the interference power level at the receiver is small, the receiver has better performance as we increase the gain of the LNA. However, when the interference level at the receiver is large, the receiver performance is heavily affected by the spurious as we increase the gain of the LNA. Thus, we proved the effectiveness of the LNA On/Off switching technique as to reduce the effect of the spurious.

• Korean Journal of Veterinary Service
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• v.17 no.2
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• pp.122-129
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• 1994

Teratogenic effects of diazinon were assessed morphologically and cholinergic blocking agents. Diazinon at doses ranging from 25 to 2000 ug /egg, was Injected on day 3 of incubation. TD50s were different for the various teratogenic signs (wry neck, micromelia, abnormal feathering, abnormal beak and curled claws). The threshould dose for wry neck was higher than threshould dose for other signs； 40 ug/egg produced substantial micromelia, abnormal feathering. abnormal beak and curled claws, but gave no signs of wry neck. In contrast to the teratogenic doses, the LD50 of diazinon was very high (above 2000 ug /egg). One of the characteristics of diazinon-induced teratogenesis was reduced body weight (78.7％) and body length (73.8%). Maximal teratogenic effects, scored as signs of retarded growth, wry neck micromelia, abnormal feathering, abnormal beak, and curled claws, were produced when the insectcide was administered on the third or fourth day. The threshold dose for type II teratogenic signs(such as wry neck and short neck) was higher than for type I (such as micromelia and abnormal feathering). Morphological studies, using atropine and gallamine, suggested that nicotine but not muscarinic receptors may be involved in the mechanism of diazinon induced type II malformations.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.7
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• pp.382-387
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• 2000

The $CdAl_2S_4 and CdAl_2S_4 : Co^{2+}$ single crystals were grown by the chemical transport reaction method using iodine as a transport agent. The $CdAl_2S_4 and CdAl_2S_4 : Co^{2+}$single crystals were crystallized into a defect chalcopyrite structure. The optical energy gap of the $CdAl_2S_4 and CdAl_2S_4 : Co^{2+}$ single crystals was found to be 3.377 eV and 2.924 eV, respectively, at 300 K. Blue emission with peaks in 456nm~466nm at 280K was observed in the $CdAl_2S_4$ single crystal. Optical absorption and emission peaks due to impurities in the $CdAl_2S_4 Co^{2+}$ single crystal were observed and described as originating from the electron transition between energy levels of the $Co^{2+} ion sited at the Td symmetry point.

• The Korean Journal of Zoology
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• v.20 no.4
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• pp.159-168
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• 1977

In order to evaluate the mutagenic potentential in mammalian system for those pesticides which were proved to be mutagenic in Salmonella microsome assay system, we have studied drug-resistant mutagenesis in cultured L5178Y cells and unscheduled DNA synthesis in human lymphocytes in vitro. We have tested five pesticides: insecticides DDVP and trichlorfon, fungicide TMTD and herbicides MO and NIP. Of these pesticides, TMTD induced weak mutation to MTX-resistance in L5178Y cells in vitro and gave positive responses in DNA repair assay system. Therefore, its potential genetic risks in human beings should be re-evaluated. DDVP and trichlorfon gave negative response in L5178Y mutagenesis test system but stimulated incorporation of $^{3}H$-TdR in DNA repar assay. MO and NIP gave also negative responses both in L5178Y mutagenesis test systemand in DNA repair assay system.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.8
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• pp.84-91
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• 2002

In this paper, we proposed a CLB-based CPLD technology mapping algorithm for power minimization under time constraint in combinational circuit. The main idea of our algorithm is to exploit the "cut enumeration and feasible cluster" technique to generate possible mapping solutions for the sub-circuit rooted at each node. In our technology mapping algorithm conducted a low power by calculating TD and EP of each node and decomposing them on the circuit composed of DAG. It also takes the number of input, output, and OR-term into account on condition that mapping can be done up to the base of CLB, and so it generates the feasible clusters to meet the condition of time constraint. Of the feasible clusters, we should first be mapping the one that h3s the least output for technology mapping of power minimization and choose to map the other to meet the condition of time constraint afterwards. To demonstrate the efficiency of our approach, we applied our algorithm to MCNC benchmarks and compared the results with those of the exiting algorithms. The experimental results show that our approach is shown a decrease of 46.79% compared with DDMAP and that of 24.38% for TEMPLA in the power consumption.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.3
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• pp.321-328
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• 1998

When we control the level of the steam generator in the nuclear power plants, a swell and shrink arises from many disturbances such as feed water rate, feed water temperature, main steam flow rate, and coolant temperature. If we use the conventional type of PI controller in this system, we will not have stability during controlling at lower power, the removal function of disturbances, and a load follow-up control effectively. In this paper, we study the application of a 2-Degree of Freedom(2-DOF) PID controller to the level control of the steam. generator of nuclear power plants through the simulation and the experimental steam generator. We use the parameters $\alpha$, $\beta$, $\gamma$ of the 2-DOF PID controller for the removal of disturbances and the parameters Kp,Ti,Td of the conventional type of PID controller for controlling setpoint. The back-propagation learning algorithm of neural network is used for tuning the 2-DOF PID controller. We can find satisfactory results of the removal of the disturbances and the tracking function in the change of setpoint through the simulation and experimental steam generator.