• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.11 no.1
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• pp.46-54
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• 2000

In this paper, PIFA on PCS handset for SAR reduction is designed. According to the position of PIFA attached on the handset, side mounted PIFA and top mounted PIFA are suggested. Resonance characteristics with variety of design parameters are analyzed. And monopole antenna with $\lambda$/4 length is designed and compared with PIFAs in bandwidth and SAR. At 1.83 GHz center frequency, the bandwidth of side mounted PIFA and monopole antenna are 8.2% and 21.7%, respectively. The 1 g and 10 g peak average SARs of side mounted PIFA are 0.686 and 0.353 respectively, which are about 1/3 of SARs of monopole antenna, 1.759 and 0.978, respectively.

• Journal of the Korean Institute of Telematics and Electronics D
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• v.35D no.12
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• pp.48-52
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• 1998

We fabricated the newly proposed nano structure memory with SOI edge channel and a nano dot. The width of the edge channel of this device, which uses the side wall as a channel and has a nano dot on this channel region, was determined by the thickness of the recessed top-silicon layer of SOI wafer. The size of side-wall nano dot was determined by the RIE etch and E-Beam lithography. The I$_{d}$-V$_{d}$, I$_{d}$-V$_{g}$ characteristics of the devices without nano dots and memory characteristics of the devices with nano dots were obtained, where the voltage scan was done between -20 V and 14 V and the threshold voltage shift was about 1 V.t 1 V.

• Journal of the Korean institute of surface engineering
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• v.41 no.6
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• pp.279-286
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• 2008

Numerical analysis is done to investigate which would be the most influencing process parameter in determining the uniformity of deposition thickness in TiN ICP-CVD(inductively coupled plasma chemical vapor deposition). Two configurations of ICP antenna are modeled; side and top planar. Side and top gas inlets are considered with each ICP antenna geometries. Precursor for TiN deposition was TDMAT(Tetrakis Diethyl Methyl Amido Titanium). Two step volume dissociation of TDMAT is used and absorption, desorption and deposition surface reactions are included. Most influencing factors are H and N concentration dissociated by electron impact collisions in plasma volume which depends on the relative positions of gas inlet and ICP antenna generated hot plasma region. Low surface recombination of N shows hollow type concentration, but H gives a bell type distribution. Film thickness at substrate edges is sensitive to gas flow rate and at high pressures getting more dependent on flow characteristics.

• Current Optics and Photonics
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• v.6 no.3
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• pp.332-336
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• 2022

Given a cubic space, it is easy to uniformly illuminate the floor with light sources placed on top. However, little has been reported about uniform illumination on walls with the same configuration of light sources. Here we present a luminaire consisting of nine light-emitting diodes (LEDs) with perfect Lambertian distribution, placed on the top as a 3 × 3 rectangular LED array. The distances between LEDs and tilt angles of each individual LED are adjustable and optimized by an annealing algorithm. After optimization, the array produces a rectangular illumination pattern on one wall with a uniformity of about 89%. Analysis shows that the tilt angles of individual LEDs are key parameters for uniform side illumination. In a scenario that is more practical, the tilt angles of all the LEDs are set to be the same, only decreasing the uniformity to 83%.

• Korean Journal of Adult Nursing
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• v.14 no.1
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• pp.135-143
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• 2002

Purpose: To explore what particular types of information were important to patients diagnosed with cancer. Methods: Seventy three patients with cancer at an outpatient clinic and hospitalized patients in W Christian Hospital Korea, responded. The structured questionnaire developed by the investigator based on previous studies. Results: There was a significant negative relationship between age and the score of informational need (r=-.307, p<.05). Level of education, and level of monthly income were related to level of informational need. The top three informational priorities according to the time since diagnosis were 'Self care during treatment', 'Health food and diet', 'Likelihood of recurrence', 'Follow up care' and 'Side effects'. The top three informational priorities for patients with breast cancer were 'Likelihood of recurrence', 'Metastasis possibility', 'Treatment options', and 'Side effects. For patients with stomach cancer, they were 'Follow up care', 'Healthy food and diet', 'Likelihood of recurrence', and 'Metastasis possibility', and for patients with colon/rectal cancer, they were 'Side effects', 'Healthy food and diet', 'Likelihood of recurrence', and 'Self care during treatment'. Conclusion: The assessment of information needs based on demographic factors and disease-related factors is critical in helping patients with cancer to manage their illness.

• Journal of the Korean institute of surface engineering
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• v.48 no.4
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• pp.174-178
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• 2015

We studied emission characteristics for blue fluorescent dual-side emission OLED with Al cathode thickness variation. In the bottom emission OLED of Al cathode with 10, 15, 20, 25, 30, and 150 nm thickness, maximum luminance showed 36.1, 8,130, 9,300, 12,000, 13,000, and $12,890cd/m^2$, and maximum current efficiency showed 2, 8.8, 10, 10.5, 10.8, and 11.4 cd/A, respectively. The emission characteristics of the bottom emission seemed to be improved according to decrease of resistance as the thickness of Al cathode increase. In the top emission OLED of Al cathode with 10, 15, 20, 25, and 30 nm thickness, maximum luminance showed 4.3, 351, 131, 88.6, and $33.2cd/m^2$, and maximum current efficiency showed 0.23, 0.38, 0.21, 0.16, and 0.09 cd/A, respectively. It yielded the highest maximum luminance and maximum current efficiency in Al cathode thickness 15 nm. It showed a tendency to decrease as the thickness of Al cathode increase. The reason for this is due to decrease of transmittance with increasing of Al cathode thickness. The electroluminescent spectra of bottom and top emission OLED were not change.

• Korean Journal of Optics and Photonics
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• v.23 no.3
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• pp.119-123
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• 2012

The structure of an LCD backlight unit (BLU) was simplified by installing a micro reverse-pyramid array (MRPA) or a micro reverse-cone array (MRCA) on the top surface of the light guide panel (LGP) in order to eliminate the conventional diffuser sheet and the prism sheet. The optimum conditions of the MRPA and the MRCA in the new light guide panel were obtained through optical simulation. The change of the luminance and view angle that depend on the side angle, the height, and the length at the top of the MRPA and MRCA were studied. The optimized side angle and the view angle of the MRPA and MRCA were 59 and 57 degrees for the side angles and 68 and 64 degrees for the view angles, respectively.

• Journal of Institute of Control, Robotics and Systems
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• v.14 no.6
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• pp.515-518
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• 2008

Organic light emitting diode(OLED) is one of the most promising type of future flat panel display. A linear source is used to deposite organic vapor to a large size OLED substrate. An electric heater which is attached on the side of linear source heats the organic powder for the sublimation. The nozzle of heater, which is attached at the top of the linear source has an optimal temperature. An numerical analysis has been performed to find optimal heater position for the optimal nozzle temperature. A commercial CFD program, FLUENT, is used on the analysis. Two-dimensional and three-dimensional analysis have been performed. The analysis showed that the heater should be attached at the outer side of crucible wall rather than inner side of housing, which was original design. Eighteen milimeter from the top of the linear source was suggested as the optimal position of heater. Improving thermal performance of linear source not only helps the uniformity of organic vapor deposition on the substrate but also increase productibity of vapor deposition process.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2004.03a
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• pp.34-40
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• 2004

Two different type scramjet models with side-wall compression and top-wall compression inlets have been tested in HPTF (Hypersonic Propulsion Test Facility) under the experimental conditions of Mach number 5.8, total temperature 1700K, total pressure 4.5㎫ and mass flow rate 3.5kg/s. The liquid kerosene was used as main fuel for the scramjets. In order to get fast ignition in the combustor, a small amount of hydrogen was used as a pilot. A strut with alternative tail was employed for increasing the compression ratio and for mixing enhancement in the side-wall compression case. Recessed cavities were used as a flameholder for combustion stability. The combustion efficiency was estimated by one dimensional theory. The uniformity of the facility nozzle flow was verified by a scanning pitot rake. The experimental results showed that the kerosene fuel was successfully ignited and stable combustion was achieved for both scramjet models. However the thrusts were still less than the model drags due to the low combustion efficiencies.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11c
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• pp.551-559
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• 2000

An integrated on-line inspection system was constructed with seven cameras, half mirrors to split images, 720 nm and 970 nm band pass filters, illumination chamber having several tungsten-halogen lamps, one main computer, one color frame grabber, two 4-channel multiplexors, and flat plate conveyer, etc., so that a total of seven images, that is, one color image from the top side of an apple and two B/W images from each side (top, right and left) could be captured and displayed on a computer monitor through the multiplexor. One of the two B/W images captured from each side is 720nm filter image and the other is 970nm. With this system an on-line grading software was developed to evaluate appearance quality. On-line test results to the Fuji apples that were manually fed on the conveyer showed that grading accuracies of the color, defective and shape were 95.3%, 86% and 91%, respectively. Grading time was 0.35 sec per apple on an average. Therefore, this on-line grading system could be used for inspection of the final products produced from an apple sorting system.