• Journal of the Institute of Electronics Engineers of Korea TE
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• v.42 no.4
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• pp.1-6
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• 2005

Recently embedded passive technology which fabricate passive elements such as resistors and capacitors at the inner layer of PCB(Printed Circuit Board) is used to make high performance IT products. However, embedded capacitor has limit in full range circuit applications because of the low capacitance density. In this paper, a new embedded capacitor which has wrinkled electrodes and dielectric layer was proposed to overcome the limits. FEM(Finite Elements Method) technique was used to evaluate capacitance density of the wrinkled type embedded capacitor. Capacitance density of the wrinkled type embedded capacitor is larger than that of conventional planar type embedded capacitor by about 25.6%$\sim$39.6%. In case of thin film type embedded capacitor, proposed wrinkled structure has more enhanced effect on the capacitance density.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.46 no.12
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• pp.65-71
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• 2009

In this paper, we propose an aircraft on-glass antenna for FM radio reception. To obtain broad matching bandwidth, we employed a multiple loop as the basic antenna structure, and the shape of the loops mimics the frame of a window in order to ensure pilots' field of view as large as possible. The detailed design parameters of the multi-loop structure were determined using a Pareto genetic algorithm with a full wave EM simulation tool. The optimized on-glass antenna was built and installed on a Korean utility helicopter (KUH) The measurement results showed a half power matching bandwidth of about 63.3 %, average vertical bore-sight gain of about -12.98 dBi in the FM band.

• 전자공학회논문지 IE
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• v.49 no.1
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• pp.1-6
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• 2012

For the performance improvement of a time-to-digital converter(TDC), a 2-stage high resolution TDC has been designed by using a 2-stage vernier time amplifier(2-S VTA). The two stage vernier time amplifier which has a gain over 64 of the resolution can enhance the resolution of the whole two stage TDC. Because of using a vernier TDC, the structure is not limited to advanced processes for achieving high resolution. The proposed TDC has been designed in a $0.18{\mu}m$ CMOS process and simulated with a 1.8V supply voltage. The entire input range is 512ps, and the full resolution 0.125ps.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2003.11a
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• pp.118-121
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• 2003

A new approach, using MEMS, for improving the performance of high efficiency amplifiers is proposed in this paper. The MEMS tuning element is described as a variable-length shorted CPW stub. Class-E amplifiers can be optimally tuned by these MEMS tuning elements because their operation varies with the impedance of the output tuning circuit. A MEMS tuning element was simulated using full-wave EM simulators to obtain its S-parameters. A Class-E amplifier with the MEMS was designed at 8GHz. The non-linear operation of this amplifier was simulated to explore the effect of the MEMS tuning. Comparing the initially designed amplifier without MEMS, the Power Added Efficiency (PAE) of the amplifier with MEMS is improved from 46.3% to 66.9%. For the amplifier with MEMS, the nonlinear simulation results are PAE = 66.90%, $\eta$(drain efficiency) = 75.89%, and $P_{out}$ = 23.37 dBm at 8 GHz. In this paper, the concept of the MEMS tuning element is successfully applied to the Class E amplifier designed with transmission lines.

• Journal of Hydrogen and New Energy
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• v.23 no.2
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• pp.162-172
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• 2012

This paper presents a research about free piston linear engine (FPLE) fueled with hydrogen, in which, the numerical models are built to simulate the operation during the full stroke of the engine. Dynamic model, linear alternator model and thermodynamic model are used as the numerical models to predict piston velocity, in-cylinder pressure and electric power of FPLE. The spark timing and air gap length are changed to provide information for the prediction. Beside, the heat transfer problem is also investigated in the paper. The results of research are divided by two parts, including motoring mode and firing mode. The result of motoring mode showed that there is validation between simulation and experiment for volume and pressure in cylinder. For firing mode, by increasing spark timing, the velocity of piston, peak pressure and electric power also increase respectively. Beside, when increasing air gap length, the electric power increases accordingly while the motion of piston is not symmetric. The effect of heat transfer also observed clearly by reducing of the peak pressure, velocity of piston and electric power.

• Proceedings of the KIEE Conference
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• 1995.11a
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• pp.502-504
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• 1995

In video image compression, it is important to extract the exact notion information from image sequence in order to perform the data compression, the field rate conversion, and the motion compensated interpolation effectively. It is well known that the location of the smallest sum of absolute difference(SAD) does not always give the true motion vector(MV) since the MV obtained via full block search is often corrupted by noise. In this paper, we first classifies the input blocks into 3 categories : the background, the shade-motion, and the edge-motion. According to the characteristics of the classified blocks, multiple locations of relatively small SAD are searched with an adaptive search window by using the proposed method. The proposed method picks MVs among those candidates by using temporal correlation. Since temporal correlation reveals the noise level in a particular region of the video image sequence, we are able to reduce the search are very effectively.

• Journal of Electrical Engineering and Technology
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• v.3 no.4
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• pp.566-570
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• 2008

Vertical nanowire SGFETs(Surrounding Gate Field Effect Transistors) provide full gate control over the channel to eliminate short channel effects. This paper presents design and characterization of a differential pair amplifier using NMOS and PMOS SGFETs with a 10nm channel length and a 2nm channel radius. The amplifier dissipates $5{\mu}W$ power and provides 5THz bandwidth with a voltage gain of 16, a linear output voltage swing of 0.5V, and a distortion better than 3% from a 1.8V power supply and a 20aF capacitive load. The 2nd and 3rd order harmonic distortions of the amplifier are -40dBm and -52dBm, respectively, and the 3rd order intermodulation is -24dBm for a two-tone input signal with 10mV amplitude and 10GHz frequency spacing. All these parameters indicate that vertical nanowire surrounding gate transistors are promising candidates for the next generation high speed analog and VLSI technologies.

• Child Health Nursing Research
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• v.13 no.2
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• pp.147-156
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• 2007

Purpose: The purpose of this study was to investigate the sleep/activity patterns of premature babies. Method: The subjects were 55 premature babies who were hospitalized in the Neonatal Intensive Care Unit (NICU) of one University Hospital in Daejeon from September 1, 2004 to March 31, 2006. The sleep/activity patterns of the premature babies were observed for 24 hours a day for 7 days. The observations were made and recorded by the researcher and 5 trained research assistants using NCASA records developed by Barnard et al. (1979). For statistical analysis, frequency, average, t-test, and Pearson correlation coefficients were used. Results: The infants slept more and had less awake periods during daytime than full-term infants. As the hospital stay of the premature babies increased, the amount of daytime sleep and total daily sleep decreased, and the amount of daytime awake periods increased. Conclusions: The findings suggest that the level of physical and physiological maturity of premature babies is one of the major variables that affect their sleep/activity patterns. Furthermore, the findings of this study will provide information about the sleep/activity patterns of premature babies, and present baseline data to develop the nursing intervention programs which support optimum development for the premature babies.

• The Journal of Korean Academic Society of Nursing Education
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• v.23 no.3
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• pp.353-362
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• 2017

Purpose: This study aimed to analyze the mobility of newly graduated nurses from regions where their nursing schools were located to regions where they took up their first jobs, and to identify factors influencing nurses' mobility. Methods: Data from the Graduates Occupational Mobility Survey, collected annually from 2010 to 2014 by the Korea Employment Information Service, were analyzed. The sample consisted of 1,488 graduates and 1,229 nurses who were employed on a full-time basis in hospitals. Multiple logistic regression analysis was conducted to identify factors associated with geographic mobility. Results: Among the nurses working in hospitals, 69.2% had their first jobs in their nursing school regions and 11.3% in their high school regions. Fifty-two percent of the nurses worked in the capital region; 47.2% thereof had moved from a non-capital region. Nurses were more likely to work in their nursing school region when they were female, were older, graduated from a high school located in their nursing school region, graduated from a college (vs. university), had a lower nursing school performance, and expected lower monthly wage, compared with those who left their nursing school region. Conclusion: Education and remuneration policies are required to reduce geographical mobility to the capital region.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4939-4942
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• 2013

The absolute necessity of cancer registration for cancer control planning is well accepted. The registry at the national or local level can provide not only essential data for cancer incidence, mortality and survival but may also point to risk and protective factors and efficacy of interventions by conducting epidemiological research. Timely publication of research findings in PubMed indexed journals is of the essence, especially in examples that allow free access so that the widest dissemination of information can be achieved. The present commentary covers the scope of research in Asia or using Asian data the period 2008-2013, nearly 40% of a total of over 300 papers being published in the APJCP. In order to reach its full potential the registry should incorporate many skills. Cooperation for this purpose, whether it be national, regional, Asia-wide or international, is a high priority and the International Agency for Research on Cancer, together with the National Cancer Institute in Thailand and the APOCP/APJCP are staging an Asian Cancer Network Forum in Bangkok in February of 2014 to allow discussion of ways forward. It is hoped that representatives from all regions of Asia will decide to attend and a l so contribute country reports for publication in a special supplement of the APJCP.