• Proceedings of the Korea Water Resources Association Conference
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• 2004.05b
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• pp.1290-1294
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• 2004

In this study, new stochastic point rainfall models which can consider the correlation structure between rainfall intensity and duration are developed. In order to consider the negative and positive correlation simultaneously, the Gumbels type-II bivariate distribution is applied, and for the cluster structure of rainfall events, the Neyman-Scott cluster point process is selected. In the theoretical point of view, it is shown that the models considering the dependent structure between rainfall intensity and duration have slightly heavier tail autocorrelation functions than the corresponding independent mode]s. Results from generating long time rainfall events show that the dependent models better reproduce historical rainfall time series than the corresponding independent models in the sense of autocorrelation structures, zero rainfall probabilities and extreme rainfall events.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.10a
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• pp.396-403
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• 2002

To eliminate deck joints, continuous span bridges are becoming an attractive option. Defferent continuty methods and construction sequences have different time-dependent effects on the behavior of the bridge system. This paper is carried out to evaluate the restraint moments generated at interior span of bridges constructed with full-span prestessed concrete bridge. Especially, effects of creep and shrinkage between ACI209-95 and Eurocode 2 are compared in this paper. Time-dependent effects in prestressed concrete bridges include creep and shrinkage of concrete. Creep due to prestress makes the girders camber up and cause positive restraint moments. The most significant effect of shrinkage in continuous bridges is the differential shrinkage that occurs because of the difference in type and age of girder and deck concrete. Differential shrinkage between the precast girder and the deck typically causes negative res03int moments.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.11 no.2
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• pp.27-37
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• 1991

The behavior of a negative buoyant flow flowing into a small reservoir is analysed by experiments and dimensional analysis. The nondimensional plunge point, head velocity, head travel distance and the dilution of density current are dependent on the inflow densimetric Froude number, Fre. The thickness of density current, flow pattern and density difference are different from two cases as follows; before the front of head arrive at the downstream end and after. Before the arrival, the thickness of density current is dependent on Fre and after the arrival, time and Fre. It was found that they can be expressed as power laws.

• The Journal of Fisheries Business Administration
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• v.51 no.1
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• pp.67-79
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• 2020

The purpose of this study is to propose a policy improvement plan by analysis of the extinction risk factors reflecting the specificity of fishing villages, fishing village support policies, and settlement conditions of fishing villages as one of the solutions to the immediate problem of fishing village extinction. The results of the study show the higher the level of number of fishing ports, number of returning rural population, and housing diffusion rate, the dependent variable extinction risk index was a positive effect while vacant house ratio and aged house ratio was analyzed to be in was a negative (-) relationship with the dependent variable.The policy implications through this study were to prepare an effective policy to reduce the risk of extinction, to improve urgent settlement conditions, and to prepare a condition to convert returning rural population into fishery population.

• Journal of the Korean Mathematical Society
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• v.43 no.3
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• pp.529-538
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• 2006

In this paper we derive the central limit theorem for ${\sum}^n_{i=l}\;a_{ni}{\xi}_{i},\;where\;\{a_{ni},\;1\;{\le}\;i\;{\le}n\}$ is a triangular array of non-negative numbers such that $sup_n{\sum}^n_{i=l}\;a^2_{ni}\;<\;{\infty},\;max_{1{\le}i{\le}n\;a_{ni}{\to}\;0\;as\;n{\to}{\infty}\;and\;{\xi}'_{i}s$ are a linearly positive quadrant dependent sequence. We also apply this result to consider a central limit theorem for a partial sum of a generalized linear process of the form $X_n\;=\;{\sum}^{\infty}_{j=-{\infty}}a_{k+j}{\xi}_{j}$.

• Proceedings of the KIEE Conference
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• 1995.07c
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• pp.1248-1251
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• 1995

This paper reports some results of an experimental investigation of planar double injection magnetic sensors. The threshold voltage proved to be very sensitive to an applied magnetic field. The magnitude and direction of the threshold voltage variation depends on the field strength and its orientation with respect to the conduction chennel. The positively-directed field pushes the carriers into the bulk causing an increase in the threhold voltage. These results seem to agree with a path modulation due to Lorentz force. The application of a negative field causes a negative variation, which is dependent on the surface recombination velocity of the silicon-$SiO_2$ interface.

• Transactions of the Korean Society of Automotive Engineers
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• v.6 no.5
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• pp.10-19
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• 1998

The erosion of electrode in spot welding of aluminium alloy by direct current is dependent on the electric polarity. The positive electrode is much more eroded than the negative one. To explain this phenomenon, Peltier effect has been generally accepted as a unique theory. In this study Peltier effect was evaluated by calculations on the basis of some references and experiments. The difference of heat generated by Peltier effect on both electrode surfaces was, however, only 4% of total heat generated during wel- ding. Because of insufficient explanation, Kohler theory, which is mainly affected by thin oxide film, was introduced. A theoretical calculation showed 17% of the temperature difference between the positive and negative electrode, in case "surface voltage" resulted from oxide film was 30% of total contact voltage. This revealed that the erosion of electrode could be more affected by Kohler theory than effect.an effect.

• Environmental Mutagens and Carcinogens
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• v.22 no.4
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• pp.255-258
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• 2002

In order to determine the safety of chemicals and pharmaceutical products, various methods can be used to evaluate the toxicity. In this study the genotoxic effect of the widely used industrial chemical, cadmium chloride, was assessed using the micronucleus test in peripheral blood of mice. The presence of micronucleated reticulocytes by microscopic observation following acridine orange staining indicated a potential genotoxic effect. The genotoxicity of intraperitoneally (i.p.) administered cadmium chloride (0.5, 1, 2 mg/kg) appeared to be dose dependent, with the maximum tolerated dose (MTD) found to be 2 mg/kg. Compared to the negative control (saline), cadmium chloride (2 mg/kg) exhibited statistically significant genotoxic potential (P<0.05) but was found to be less than the positive control of mitomycin C (0.5 mg/kg) and was not statistically significant compared to historical negative controls (P>0.05).

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1075-1078
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• 2007

Negative Bias Temperature Instability (NBTI) in Eximer Laser Annealing (ELA) based Low Temperature polysilicon (LTPS) Thin-Film Transistors (TFT) was investigated. Even though NBTI is generally appeared in devices with thin gate oxide, the TFT with gate oxide thickness of 120 nm, relatively thick, also showed NBTI effect and dynamic NBTI effect is dependent on operational frequency.

• Proceedings of the IEEK Conference
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• 2003.07b
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• pp.687-690
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• 2003

Experimental results are presented for gate oxide degradation and its effect on device parameters under negative and positive bias stress conditions using NMOSFET's with 3 nm gate oxide. The degradation mechanisms are highly dependent on stress conditions. For negative gate voltage, both hole- and electron-trapping are found to dominate the reliability of gate oxide. However, with changing gate voltage polarity, the degradation becomes dominated by electron trapping. Statistical parameter variations as well as the "OFF" leakage current depend on those charge trapping. Our results therefore show that Si or O bond breakage by electron can be another origin of the investigated gate oxide degradation.gradation.