• Journal of the Institute of Electronics Engineers of Korea TC
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• v.42 no.6 s.336
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• pp.1-8
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• 2005

This paper presents a new low-cost fault-based Built-In Self-Test (BIST) scheme and technique for 1.8GHz RF receiver front end. The technique utilizes input impedance matching measurement. The BIST block and RF receiver front end are designed using 0.25m CMOS technology on a single chip. The technique is simple and inexpensive. The overhead of the BIST circuit is approximately $10\%$ of the total area of the RF front end.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.43 no.3 s.345
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• pp.68-77
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• 2006

This paper presents a new Design-for-Testability (DfT) circuit for 4.5-5.5GHz low noise amplifiers (LNAs). The DfT circuit measures gain, noise figure, input impedance, input return loss, and output signal-to-noise ratio for the LNA without external expensive equipment. The DfT circuit is designed using 0.18m SiGe technology. The circuit utilizes input impedance matching and DC output voltage measurements. The technique is simple and inexpensive.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2003.09a
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• pp.140-143
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• 2003

Air permeabilities in unsaturated fractured tuff at the Apache Leap Research Site (ALRS) near Superior, Arizona, exhibit a self-affine behavior, thus renders a field random fractal. Based up fractal scaling, the observed scale effect has been interpreted [Hyun et al., 2002]. Recently, Frantziskonis and Hansen [2000] presented that fractal scaling can be represented based on wavelets. This study deals with the way of using wavelets for fractal scaling. A numerical study is presented to examine the applicability of wavelet-based approach to determining upscaled air permeability values on various data supports at the site. To characterize the scaling property of self-affine fields generated based upon wavelets, Hurst coefficient, H. was inferred by applying the average wavelet coefficient (AWC) method. The result yielded H = 0.24, which is very close to the result of geostatistical analysis using a power variogram (H = 0.22). The study concludes that wavelet-based scaling is a useful way of determining parameter values on different data supports, which is an essential task for modeling of subsurface flow and mass transport in a numeric grid with different resolutions (grid size).

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.31.1-31.1
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• 2018

While astronomers are working hard to detect the earliest galaxies and to follow their evolution to redshift z~0, they remain baffled by the present-day dichotomy between disky, star forming (aka late-type) galaxies and quiescent, spheroidal (aka early-type) galaxies. The key is to find galaxies in transition from one class to the other, whose spectra indicate intense recent star formation that has now ended. We have identified thousands of such "post-starburst galaxies" and discovered that they are often the products of late-type galaxy-galaxy mergers. Their current kinematics, stellar populations, and morphologies are consistent with late- to early-type galaxy evolution. I will discuss recent work that suggests new connections between this violent history and the central supermassive black hole. In particular, the molecular gas reservoir of a post-starburst galaxy declines rapidly after the starburst ends and in a manner consistent with feedback from an active nucleus. Furthermore, a star is ~300x more likely to be tidally disrupted by the nucleus of a post-starburst galaxy than in other galaxies. Like the well-known black hole-bulge mass correlation, these surprising links between the properties of a galaxy on kpc scales and its supermassive black hole on pc scales require explanation.

• Child Health Nursing Research
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• v.13 no.2
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• pp.136-146
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• 2007

Purpose: The purpose of this study was to develop a tool to assess the severity of illness in high risk newborns. Method: The research design was a methodological study. The tool was developed in 4 stages: first, preliminary items were developed based on a questionnaire about the severity of illness index that was given to 8 health professionals in Neonatal Intensity Care Units (NICU) second, a panel of specialists reduced the preliminary items using 3 validity tests; third, final items were selected from the results of a pre-test. Finally, from July 2005 to May 2006, reliability and validity were tested with a sample of 160 high risk newborns admitted to the NICU. Results: The final tool to identify the severity of illness index in high risk newborns consisted 39 items and Cronbach's alpha coefficient for internal consistency was .922. Using factor analysis, 4 factors were extracted and these factors explained 54.451% of the total variance. Conclusion: The instrument for assessing the severity of illness in high risk newborns developed in this study was identified as a tool with a high degree of reliability and validity. In this sense, this tool can be effectively utilized for assessing and implementing care for high risk newborns.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.378.2-378.2
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• 2014

We have investigated optical characteristics of $p-Ge_{0.99}Sn_{0.01}$ and Ge films grown on Si substrates using photoreflectance (PR) spectroscopy. The $Ge_{0.99}Sn_{0.01}$ and Ge films were grown by using an ultra-high vacuum chemical vapor deposition and molecular beam epitaxy methods, respectively. PR spectra were measured at 25 K and an extended InGaAs detector was used. By comparing $Ge_{0.99}Sn_{0.01}/Si$ and Ge/Si spectra, we observed the signals related to direct transition and split-off band of $Ge_{0.99}Sn_{0.01}$. The transition energies of $Ge_{0.99}Sn_{0.01}$ and Ge films were approximately 0.74 and 0.84 eV, respectively. Considering the shift of split-off band transition of $Ge_{0.99}Sn_{0.01}$, we suppose that the transition at 0.74 eV is attributed to direct transition between ${\Gamma}$ band and valence band. The temperature- and excitation power-dependent PR spectra were also measured.

• Journal of Distribution Science
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• v.15 no.11
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• pp.21-29
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• 2017

Purpose - Relationship between farm and county losses determines whether the county program provides too little, too much, or similar amount of assistance relative to the loss on an individual farm. A review of the literature finds limited analysis of the determinants of this relationship. This paper conducts such an analysis using farm-level yield data. Research design, data, and methodology - Farm-level yield data from Illinois and Kansas farm business management associations are used for to calculate the correlation between farm and county loss and the share of farm loss systemic with county loss, and also for the regression analysis. Results - Average share of farm loss systemic with the county loss lies between 42% and 68%. The correlation between farm and county yield/revenue deviation from expected value is statistically significant in all four models. The coefficient is positive, implying the higher the correlation, the larger the share of farm loss that is systemic with the county loss. Conclusions - The findings of this study are consistent with the existing literature which argues that county variability may not be closely associated with farm variability. The findings of this study thus raise questions about the efficacy of area yield and revenue insurance products in helping farmers manage their risk.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.9 no.4
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• pp.36-51
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• 2006

Although the demand and necessity for the facilities of nature environmental conservation and its utilization have been increased recently, the local governments has been experiencing difficulties to launch the facilities since there are no confirmed principles or guidelines for the direction of the facility and distinctions from the ordinary parks. In this regard, the aim of this paper is to provide the overall framework for establishing the facility by equipping checklists from planning to operational stage. The stages are disengaged into 5 steps of siting feasibility, planning, preliminary environmental assessment and environmental impact assessment, design, construction, and operation. This paper also include the recommendations to vitalize the existing facilities, of which expansion of educational program development; utilization of various manpower; provision of appropriate settings; strengthened monitoring; and increased public relations. Furthermore, it is suggested to consider the strengthened local characteristics, reviewing management plan at the stage of applying a new facility establishment to the concerned authority, fostering experts, and expansion of the facilities through restoration of environmentally damaged areas for a new facility.

• Korean Journal of Remote Sensing
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• v.31 no.4
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• pp.303-319
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• 2015

The objectives of this paper are to measure surface imperviousness using three different classification methods: per-pixel, sub-pixel, and object-oriented classification. They are tested on high-spatial resolution QuickBird data at 2.4 meters (four spectral bands and three principal component bands) as well as a medium-spatial resolution Landsat TM image at 30 meters. To measure impervious surfaces, we selected 30 sample sites with different land uses and residential densities across image representing the city of Phoenix, Arizona, USA. For per-pixel an unsupervised classification is first conducted to provide prior knowledge on the possible candidate spectral classes, and then a supervised classification is performed using the maximum-likelihood rule. For sub-pixel classification, a Linear Spectral Mixture Analysis (LSMA) is used to disentangle land cover information from mixed pixels. For object-oriented classification several different sets of scale parameters and expert decision rules are implemented, including a nearest neighbor classifier. The results from these three methods show that the object-oriented approach (accuracy of 91%) provides more accurate results than those achieved by per-pixel algorithm (accuracy of 67% and 83% using Landsat TM and QuickBird, respectively). It is also clear that sub-pixel algorithm gives more accurate results (accuracy of 87%) in case of intensive and dense urban areas using medium-resolution imagery.

• Journal of Families and Better Life
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• v.19 no.2
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• pp.13-21
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• 2001

The purpose of this study is to examine the Marriage Preparation and Preservation Act adopted in Florida which require premarital counseling and covenant marriage laws of Louisiana and Arizona among many kinds of family policy which recently are designed to prevent divorce in the United States of America. Most of states in the U.S. require the marriage license prior to having a marriage ceremony. Covenant marriage legislation has admirable motives to strengthen marriage and cure the defects of the no-fault system. In that legislation, the imposition of waiting period for the no-fault ground of divorce, proof of fault requirements, consent requirements, and mandatory course or counseling attendance will likely serve as deterrents to those seeking divorce as a first resort. To sum up, by offering preventive measures in the form of premarital counseling and waiting period before marriage, covenant marriage will force couples entering marriage to carefully consider their actions before they act and prevent broken marriages in the first place. In response to rising divorce rates, the Koreas family policy has put its emphasis of fixing social problems accompanied with family dissolution. Rather, this study suggests that attention in Korea also should be shifted from broken marriages to preventing them.