• Journal of Sensor Science and Technology
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• v.11 no.5
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• pp.273-278
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• 2002

An intrusion-sensitive capability of multimode graded-index (GRIN) optical fibers under bending has been investigated. In this system, the data light is transmitted in the fundamental mode while alarm monitor light is launched in a high-order mode at the same time. An attempted intrusion to drain data by bending the fiber results in greater attenuation of a monitor signal in higher order modes, thereby setting off an alarm at the receiver. Light propagation in a multimode graded-index fiber is also analyzed theoretically when the fundamental mode is selectively excited and the fiber is bent around a constant radius mandrel. The bending generates coupling between the various modes of the fiber. Power transitions of the fundamental mode by changing the bending radius were also analyzed numerically using program simulation. It is shown that Asawa-Taylor model[4] is valid up to 1cm of the radius of curvature of the fiber bend.

• Proceedings of the Korean Society of Life Science Conference
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• 2001.11a
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• pp.3-8
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• 2001

Isopentenyl diphosphate (IPP) is the common, five-carbon building block in the biosynthesis of all carotenoids, IPP in Escherichia coli is synthesized through the non-mevalonate pathway. The first reaction of IPP biosynthesis in E. coli is the formation of 1-deoxy-D-xylulose-5-phosphate (DXP), catalyzed by DXP synthase and encoded by dxs. The second reaction in the pathway is the reduction of DXP to 2-C-methyl-D-erythritol-4-phosphate, catalyzed by DXP reductoisomerase and encoded by dxr. To determine if one or more of the reactions in the non-mevalonate pathway controlled flux to IPP, dxs and dxr were placed on several expression vectors under the control of three different promoters and transformed into three E. coli strains (DH5(, XL1-Blue, and JM101) that had been engineered to produce lycopene. Lycopene production was improved significantly in strains transformed with the dxs expression vectors. When the dxs gene was expressed from the arabinose-inducible araBAD promoter (PBAD) on a medium-copy plasmid, lycopene production was 2-fold higher than when dxs was expressed from the IPTG-inducible trc and lac promoters (Ptrc and Plac, respectively) on medium-copy and high-copy plasmids, Given the low final densities of cells expressing dxs from IPTG-inducible promoters, the low lycopene production was probably due to the metabolic burden of plasmid maintenance and an excessive drain of central metabolic intermediates. At arabinose concentrations between 0 and 1.33 mM, cells expressing both dxs and dxr from PBAD on a medium-copy plasmid produced 1.4 - 2.0 times more lycopene than cells expressing dxs only. However, at higher arabinose concentrations lycopene production in cells expressing both dxs and dxr was lower than in cells expressing dxs only. A comparison of the three E. coli strains transformed with the arabinose-inducible dxs on a medium-copy plamid revealed that lycopene production was highest in XL1-Blue.

• Journal of The Korean Society of Agricultural Engineers
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• v.59 no.4
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• pp.43-52
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• 2017

This study analyzed pore water pressure, earth pressure and settlement through laboratory model tests in order to suggest the effective remodeling method in the case of reinforcing the upstream and downstream slope of deteriorated reservoirs that has no cores and filters or is not functional. The method of remodeling the upstream slope using dredge soil is first prevent seepage by installing the core, and the leakage water can be rapidly discharged through a filter installed on the downstream slope. Therefore, it is considered a highly efficient method of remodeling that reduces piping phenomena and increasing the storage capacity of the reservoir. The variation of earth pressure without the core and filter was greater than with it, while the change largely showed in the upstream slope, the downstream slope did not show any significant changes. The remodeling method of the downstream slope with the core appeared differently pore water pressure depending on the presence of the vertical and horizontal filters. In the upstream slope, the pore water pressure rises sharply, the base and middle gradually increased, and the downstream slope appeared small. The pore water pressure of embankment with a vertical and horizontal filter will be smaller than without it. The remodeling of deteriorated reservoir that does not have the function of the filter, the vertical filter must be installed in a position that is higher than the expected seepage line by removing portions of the downstream slopes. Since the horizontal filter is an important structure that provides stable drainage during an earthquake or concentrated leak, it is necessary to examine any change in the seepage characteristics depending on the filter intervals via three-dimensional finite element analysis, and it should be connected to the tow-drain to reduce the possibility of the collapse of the reservoir.

• Asian Journal of Turfgrass Science
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• v.18 no.2
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• pp.77-95
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• 2004

This study was conducted to find out definition, specification and characteristics of water-proof method for pond at golf courses that located in the mountain in Korea. Water-proof method of pond was selected by location, kind of soil, area, depth, cost, construction period and so on. 1. Soil Bentonite Sealing Liner(SBL) is to mix soil with a good quality bentonite. Then the mixed material was dressed on the bottom of pond. $\\$Merit of SBL is to purify the water and planting is possible. It can also reduce construction period and is economical. It's easy to find out the leak points. Demerit of SBL is expensive, if good quality soil is not in constructing site. Shape of pond edge is simple. 2. Ethylen Propylene Diene Monomer Sheef(EPDM-Sheet) makes use of sheet that resists to acid and alkaline. EPDM-Sheet spreads out as a mat on the pond for water-proof. Merit of EPDM-Sheet is to perfectly prove water and make a diverse shape of pond edge. Demerit of EPDM-Sheet is not friendly to environment. It needs drain system, air ventilation and long period of construction. It is also difficult to find out leaking points in this method. 3. Water proof of ESS-13 uses ESS-13 that is resin of vegetable matter and friendly to environment. To prove water of pond, ESS-13 is delicate with water in the pond. After that, Ess-13 in the water is expanded at pore space in the soil and cover with soil. ESS-13 can be to prove a leaking pond in golf course under business. ESS-13 is cheap and it needs short construction period. It does not need to switch the old water-proof system, additionally. It needs to move fishes to other place before utilizing ESS-13.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2011.05a
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• pp.681-684
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• 2011

In this paper, the relationship of potential and charge distribution in channel for double gate(DG) MOSFET has been derived from Poisson's equation using Gaussian function. The subthreshold swing has been investigated according to projected range and standard projected deviation, variables of Gaussian function. The analytical potential distribution model has been derived from Poisson's equation, and subthreshold swing has been obtained from this model. The subthreshold swing has been defined as the derivative of gate voltage to drain current and is theoretically minimum of 60mS/dec, and very important factor in digital application. Those results of this potential model are compared with those of numerical simulation to verify this model. As a result, since potential model presented in this paper is good agreement with numerical model, the subthreshold swings have been analyzed according to the shape of Gaussian function.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.36D no.11
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• pp.27-32
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• 1999

Metal-ferroelectric-semiconductor devices by susing rapid thermal annealed $LiNbO_3/Si$(100) structures were fabricated and demonstrated nonvolatile memory operations. The estimated field-effect electron mobility and transconductance on a linear region of the fabricated FET were about $600cm^2/V{\cdot}s$ and 0.16mS/mm, respectively. The ID-VG characteristics of MFSFET's showed a hysteresis loop due to the ferroelectric nature of the $LiNbO_3 films. The drain current of the on state was more than 4 orders of magnitude larger than the off state current at the same read gate voltage of 0.5V, which means the memory operation of the MFSFET. A write voltage as low as ${\pm}3V$, which is applicable to low power integrated circuits, was used for polarization reversal. The ferroelectric capacitors showed no polarization degradation up to $10^{10}$ switching cycles with the application of symmetric bipolar voltage pulse (peak-to-peak 6V, 50% duty cycle) of 500kHz.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.1
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• pp.155-162
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• 1990

In analysis of deformation in which the stiffness is greatly different between the adjacent materials, the desired results have been obtained by using the interface element method compared with those secured by the conventional method of the concept of continua. However the interface element method was originally developed for the behavior of rocks. This study deals with the deformation analysis of foundation with sand drain by the introduction of interface element. The physical conditions of interface element are devided into three categories by Mohr-Coulomb failure criterion ie. sliding, separation, and contact. Finally the accuracy of the program proposed in this paper is proved highly accurate by performing the comparison of the theoretical values and numerical results of a model element with simplified boundary conditions.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.17 no.1
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• pp.153-158
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• 2017

Rendezvous point is used to gather the data from sensor nodes and send to sink node efficiently in selected area. It incurs a unbalanced energy consumption nearby the rendezvous point which can shorten the network life time shortly. Thus, it is very important to select the rendezvous point effectively among all sensors in order to not drain the battery of a sensor node in construction sites. In this paper, we propose a rendezvous point replacement mechanism which considers remaining energy of nodes to prolong the network lifetime. Also, for shortening the distance of drone at the same time, it increases the probability of the near-by drone node becoming rendezvous point. The simulation results show that the proposed scheme can significantly improve the network lifetime and the flight distance compared with the existing LEACH, L-LEACH algorithm.

• Journal of the Institute of Electronics and Information Engineers
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• v.52 no.3
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• pp.190-195
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• 2015

The detection of single nucleotide polymorphisms (SNPs) caused of mutant or genetic diseases is important to diagnosis and medicine. There are many methods have been proposed to detect SNPs. However the detection of SNPs is difficulty, because the difference of energy between complementary DNA (cDMA) and SNPs is very small. In this work, we detect the SNPs using field-effect transistors (FETs) which based on the detection of negative charge of DNA. We bias -0.3 V on the drain-source electrode at the target DNA hybridization process. The efficiency of hybridization and the amplitude of signal decrease by repulsive force between negative charge of DNA and negative bias on the electrode. However, the sensitivity of SNPs increases about 5 times from 1.7 mV to 8.7 mV.

• Geotechnical Engineering
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• v.12 no.5
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• pp.41-54
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• 1996

In this paper, the consolidation settlement of the landfill foundation during and after the period of disposal is analyzed using the program CONSOL which can include the influence of waste load and the leachate level into the analysis. the stability analysis of the embankment is also performed under the varied strength of foundation soil which results from the increase of effective stress due to consolidation of the clay under the landfill. The predicted settlement from CONSOL is compared with the field measured settlement. The results show that, when the leachate level increases with the increase of waste height, the increase of the effective stress of foundation clay is negligible and the stability of the slope of the landfill may not be secured as the disposal of the waste proceeds. Several complementary repairworks, e. g. the reduction of current slope of the fill, application of drain methods to stop or reduce !he leachate level are recommended. The predicted settlement consists moderately with the field measured settlement.