• Journal of the Korean Ceramic Society
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• v.47 no.4
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• pp.329-332
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• 2010

In order to investigate the effect of tail state on the electrical and the optical properties in amorphous IGZO(a-IGZO), a-IGZO films were deposited at room temperature on fused silica substrats using pulsed laser deposition method. The laser pulse energy was used as the processing parameter. In-situ post annealing was carried out at $150^{\circ}C$ right after the film deposition. The $O_2$ partial pressure during the deposition and the post annealing was fixed to 10mTorr. The carrier mobility of the a-IGZO films had a range from 2 to $18\;cm^2/Vs$ at carrier concentrations greater than $10^{18}\;cm^{-3}$. As the laser energy density increased, the Hall mobility increased. And post annealing improved the Hall mobility, as well. The optical property was examined using the ultraviolet-visible spectroscopy. The a-IGZO films that have low Hall mobility exhibited stronger and broader absorption tails in >3.0 eV region. Post annealing reduced the intensity of the tail-like absorption. The absorption tail in a-IGZO films is an important factor which affects the electrical and the optical properties.

• Asian-Australasian Journal of Animal Sciences
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• v.18 no.5
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• pp.643-648
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• 2005

Near infrared reflectance spectroscopy (NIRS) has become increasingly used as a rapid, accurate method of evaluating some chemical constituents in cereal grains and forages. If samples could be analyzed without drying and grinding, then sample preparation time and costs may be reduced. This study was conducted to develop robust NIRS equations to predict fermentation quality of corn (Zea mays) silage and to select acceptable sample preparation methods for prediction of fermentation products in corn silage by NIRS. Prior to analysis, samples (n = 112) were either oven-dried and ground (OD), frozen in liquid nitrogen and ground (LN) and intact fresh (IF). Samples were scanned from 400 to 2,500 nm with an NIRS 6,500 monochromator. The samples were divided into calibration and validation sets. The spectral data were regressed on a range of dry matter (DM), pH and short chain organic acids using modified multivariate partial least squares (MPLS) analysis that used first and second order derivatives. All chemical analyses were conducted with fresh samples. From these treatments, calibration equations were developed successfully for concentrations of all constituents except butyric acid. Prediction accuracy, represented by standard error of prediction (SEP) and $R^2_{v}$ (variance accounted for in validation set), was slightly better with the LN treatment ($R^2$ 0.75-0.90) than for OD ($R^2$ 0.43-0.81) or IF ($R^2$ 0.62-0.79) treatments. Fermentation characteristics could be successfully predicted by NIRS analysis either with dry or fresh silage. Although statistical results for the OD and IF treatments were the lower than those of LN treatment, intact fresh (IF) treatment may be acceptable when processing is costly or when possible component alterations are expected.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.8
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• pp.1110-1114
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• 2002

The animal production sector in Jordan is characterized by shortages of locally produced feedstuffs derived from rangeland, forage plants or from human food crops as by products. This is exacerbated by insufficient rainfall, overgrazing, early grazing and high stocking rate. Thus, subject to these constraints, other technological improvements are highly desirable to meet the needs of crop growth and animal production. Alternative adapted technologies are also desirable in order to meet the increased demand for red meat in relation to population growth along with the changes in the price subsidy for feedstuff. The technologies are those, which have been introduced to the animal production sector, obtained in agricultural research stations besides on-farm demonstrations. They include technologies suited for increasing birth and twining rates, synchronizing the mating period, introducing the early weaning method, and animal feed and sheep production. Economic assessments conducted in this study demonstrate promising results of hormonal and nutritional practices in improving production efficiency of Awassi sheep in Jordan. Jordanian published data between 1991 and 1998 were used. The examined practices were: 1) use of PMSG in estrus synchronization in ewes, 2) introduction of early lamb weaning program, 3) supplementation with $AD_3E$ for ewes and 4) the use of agro-industrial feed block as a feed supplement for grazing lambs. Production data were then subjected to partial budgeting for economical evaluation. The use of PMSG outperformed the control groups in fertility and net returns per ewe by US$ 8.36/ewe. The early weaning of lambs increased the net returns by US$ 3.90/lamb. The injection with vitamin $AD_3E$ showed an average additional net return of US$ 5.66/ewe. Feeding agriculture by-product blocks improved weight gain in the feed block groups and resulted in additional net returns of US$ 3.5/lamb. The economic viability and reproductive performance indicators demonstrate that efforts should be undertaken to disseminate these new practices in the development program.

• Proceedings of the KIEE Conference
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• 2002.07c
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• pp.1668-1670
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• 2002

Since more than two decades, the conventional PD detecting systems have been employed in order to detect the partial discharges occurring inside the HV power apparatus for their diagnosis by use of different type of detection such as acoustic and UHF detection method. Regardless of their wide on-site application, a certain number of technical inconveniences have been disclosed as follows : multistage amplification. large volume, susceptible to external noise and high price. In this respect, the optical measurement techniques are widely proposed in these days in this concerned field ascribed to the following advantages : immune to external EMI noise and broad band response of the Pockels cell covering from DC to GHz. However, the reliability of several proposed techniques enabling to measure the electric field inside the large high power apparatus has not yet been well approved In this work, an optical measuring system, based on the Pockels effect, has been developed for measuring the field variation due to the corona discharges occurring in air and in oil. This system consists of He-Ne laser, single mode optical fiber, multi mode optical fiber, polarizing film, Y-cut LiNbO3 cell, photo detector, digital oscilloscope and personal computer with GPIB. For this purpose, optical probe has been specially designed and realized and put into the needle-plane electrode. Afterward, same measurement is carried out in oil. We demonstrate the characteristic of the optical measuring system and the measurement results.

• Membrane Journal
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• v.16 no.3
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• pp.204-212
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• 2006

A numerical analysis was carried out for separation of carbon dioxide from carbon dioxide/nitrogen gas mixture by a polyethersulfone hollow fiber membrane which has shown a good stability against plasticization by carbon dioxide and an excellent separation efficiency fur carbon dioxide from its gas mixture. A computer program for carbon dioxide separation was developed using the Compaq Visual Fortran 6.6 software. Governing module equations were thought to be an initial-value problem and the nonlinear ordinary differential equations were simultaneously solved using the Runge-Kutta-Verner fifth-order method. From results of numerical analysis, the carbon dioxide partial pressure of the feed stream, the pressure ratio of the feed side to the permeate side and the feed gas residence time at the inside of a membrane were found to be very important factors to affect the permeation characteristics of carbon dioxide.

• Journal of KIISE:Computing Practices and Letters
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• v.7 no.5
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• pp.451-457
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• 2001

This paper describes automated methods for the detection of lung nodules and their volume calculation on CT scans. Gray-level threshold methods were used to segment the thorax from the background and then the lung parenchymes from the thoracic wall and mediastinum. A scanning-ball algorithm was applied to more accurately delineate the lung boundaries, thereby incorporating peripheral nodules contiguous to pleural surface within the segmented lung parenchymes. The lesions which have the high gray value were extracted from the segmented lung parenchymes. The selected lesions include nodules, blood vessels and partial volume effects. The discriminating features such as size, solid-shape, average, standard deviation and correlation coefficient of selected lesions were used to distinguish true nodules from pseudo-lesions. Volume and circularity calculation were performed for each identified nodules. The identified nodules were sorted in descending order of the volume. These method were applied to 621 image slices of 19 cases. The sensitivity was 95% and there was no false-positive result.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.4
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• pp.349-358
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• 2000

Fabrication and Characterization of Bi$_{2}$/Sr$_{2}$/CaCu$_{2}$/O$_{8}$(Bi2212) superconductor thick films were fabricated successfully on C tapes by liquid reaction between Cu-free precursors of Bi$_{x}$/SrCaO/$_{y}$(x=1.2-2) and Cu tapes. Cu-free Bi-Sr-Ca-O powder mixtures were screen-printed on Cu tapes and heat-treated at 850-87$0^{\circ}C$ for several minutes in air oxygen nitrogen and low oxygen pressure. In order to obtain the optimum heat-treatment condition we studied the effect of the precursor composition the printing thickness and the heat-treatment atmosphere on the superconducting properties of Bi2212 films and the reaction mechanism. Microstructures and phases of thick films were analyzed by films and the reaction mechanism. Microstructures and phases of thick films were analyzed by optical microscope and XRD. The electric properties of superonducting films were examined by the four probe method. At heat-treatment temperature the thick films were in a partially molten state by liquid reaction between CuO of the oxidized copper tape and the precursors which were printed on Cu tapes. During the heat-treatment procedure Bi2212 superconducting particle nucleate and grow in preferred orientations.ons.s.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.28 no.1
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• pp.46-50
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• 2015

The cable degradation process is largely divided into three steps; Step 1 : Thermal degradation, Step 2 : Weibull degradation, Step 3 : Partial discharge. it is progress in step order. This article aims to explain the process of cable degradation using the method of insulation resistance and accordingly to compose and manufacture a system of measuring the life of electrical cable. Before measuring the insulation resistance, a system of measuring the temperature and current of cables was made, and the established system was installed for test on the site of a power plant to collect the measured data. The current sensor was used TFC30P80A-CL420, and temperature sensor was used the DK-1270 PT100 sensor as RTD sensor. When measured the temperature and the load current at the same position, was confirmed that in case of the load current value was high, also temperature value high. Therefore, the correlation between load currents and temperature was verified, and the analysis of diagnostic data was evaluated, which could be utilized in identifying the fault condition of cable systems.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.05a
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• pp.9-9
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• 2009

Coated conductor is required to have good critical current property for high efficiency of electric power applications. Until now, long coated conductor does not show high Jc over 3 MA/$cm^2$ in thick superconducting layer because of texture degradation by thick superconducting layer. In this study, in order to overcome this issue, thicker superconducting layer was deposited with optimized conditions to reduce the degradation of critical current density. SmBCO superconducting coated conductor was deposited with 1~3 um of thickness at $750\sim850^{\circ}C$ under 15~20 mTorr of oxygen partial pressure using batch type EDDC( evaporation using drum in dual chamber). The buffered substrate for superconducting layer deposition was used IBAD-MgO template with the architecture of $LaMnO_3/MgO/Y_2O_3/Al_2O_3$/Hastelloy. After fabrication of coated conductor, critical current was measured by 4-prove method under self-magnetic field and 77K. In addition, surface morphology and texture were analyzed by SEM and XRD, respectively. 3 um thick SmBCO coated conductor shows highest $I_C$ values of 638A/cm-w in 1 m long in the world.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.22 no.6
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• pp.648-653
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• 2011

In this paper, coordinated space division multiple access(SDMA) technology is proposed to mitigate inter-cell interference by using partial channel state information in cooperative wireless communications system with limited feedback. Each AT selects an optimal cluster transmission mode and sends it back to a cluster scheduler, and at the cluster scheduler, ATs are scheduled within a AT group with the identical cluster transmission mode, and the optimal transmission mode and the corresponding scheduled ATs are determined to maximize scheduling priority. Also, in order to enhance multiuser diversity gain, an extended transmission feedback method is proposed to feed back multiple preferred cluster transmission modes at each AT. It is shown that the proposed coordinated SDMA scheme outperforms existing non-coordinated SDMA schemes in terms of the average system throughput.