• Journal of Korean Society for Atmospheric Environment
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• v.21 no.4
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• pp.439-458
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• 2005

An automated analysis system for water soluble constituents in $PM_{2.5}$ has been developed. The system consists of a high capacity multi tube diffusion scrubber (MTDS), a low temperature particle impactor (LTPI), and two ion (anion and cation) chromatography (IC) systems. Atmospheric particles have been collected by passing sample air through a thermostated MTDS followed by a LTPI. This system allows simultaneous measurements of soluble ions in $PM_{2.5}$ at 30 minutes interval. At the air sampling flow rate of 1.0L/min, the detection limits of the overall system are in the order of tens of $ng/m^3$. This system has been successfully used for the measurement of particulate components of Seoul air from April 2003 to January 2004. $SO_4^{2-},\;NO_3^-,\;NH_4^+,\;NO_2^-,\;Cl^-,\;Na^+,\;K^+,\;Ca^{2+},\;and\;Mg^{2+}$ are the major ionic species for $PM_{2.5}$ at Seoul. Among them, $SO_4^{2-},\;NO_3^-\;and\;NH_4^+$ are the most abundant ions, contributed up to $86\%$ of the total and the concentrations were higher than those in any other urban sites in the world except for Chinese cities. There are high pollutant episodes which contribute about $15\~20\%$ of annual average values of the major ions. During the episode, the all parcels were transported from the asian continent and $PM_{2.5}$ were significantly neutralized. This suggests that aged and long range transported pollutants caused the high pollutant episodes. They showed a distinct daily and seasonal variations:they showed a peak in the early morning caused by the night-time accumulation of particulate matters. Atmospheric reactions including gas-to-particle reactions and inter-particle reactions and meteorological parameters including relative humidity and ambient temperature were described with related to the $PM_{2.5}$ 5 concentrations. All of the ionic species showed higher concentrations during the spring than those for summer and winter.

• Proceedings of the Korean Geotechical Society Conference
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• 2008.10a
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• pp.1115-1123
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• 2008

When constructing projects such as road embankments, bridge approaches, dikes or buildings on soft, compressible soils, significant settlements may occur due to the consolidation of these soils under the superimposed loads. The compressibility of the soil skeleton of a soft clay is influenced by such factors as structure and fabric, stress path, temperature and loading rate. Although it is possible to determine appropriate relations and the corresponding material parameters in the laboratory, it is well known that sample disturbance due to stress release, temperature change and moisture content change can have a profound effect on the compressibility of a clay. The early research of Tezaghi and Casagrande has had a lasting influence on our interpretation of consolidation data. The 24 hour, incremental load, oedometer test has become, more or less, the standard procedure for determining the one-dimensional, stress-strain behavior of clays. An important notion relates to the interpretation of the data is the ore-consolidation pressure ${\sigma}_p$, which is located approximately at the break in the slope on the curve. From a practical point of view, this pressure is usually viewed as corresponding to the maximum past effective stress supported by the soil. Researchers have shown, however, that the value of ${\sigma}_p$ depends on the test procedure. furthermore, owing to sampling disturbance, the results of the laboratory consolidation test must be corrected to better capture the in-situ compressibility characteristics. The corrections apply, strictly speaking, to soils where the relation between strain and effective stress is time independent. An important assumption in Terzaghi's one-dimensional theory of consolidation is that the soil skeleton behaves elastically. On the other hand, Buisman recognized that creep deformations in settlement analysis can be important. this has led to extensions to Terzaghi's theory by various investigators, including the applicant and coworkers. The main object of this study is to suggestion the modified compression index value to predict settlements by back calculating the $C_c$ from different numerical models, which are giving best prediction settlements for multi layers including very thick soft clay.

• Korean Journal of Health Education and Promotion
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• v.26 no.2
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• pp.75-86
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• 2009

Objectives: To identify the factors associated with the intention to undergo mammography among Korean women without a prior screening experience. Methods: Among 1,039 women of the general population, we selected 145 women (mean age: 54.2 years, age range : 40-78 years) without any prior experience with mammography. They were recruited for the 'Cancer Information Needs Assessment Survey' by using the method of random multi-stage cluster sampling. Data on the socio-demographic characteristics, intention to undergo mammography based on the Precaution Adoption Process Model, level of self belief and self efficacy for breast cancer screening, motivation for decision to undergo breast cancer screening were obtained by conducting a household survey. Results: Of the study subjects, 49.7% were classified as "unengaged" and "decided not to act" regarding breast cancer screening. Women with the intention to undergo mammography were more likely to be younger (OR 0.11, 95%CI 0.04-0.36), to have been recommended to undergo screening by others (OR 3.27, 95%CI 1.36-7.87), to have a high level of perceived sensitivity (OR 3.15, 95%CI 1.27-7.82), and to have a high level of self efficacy (OR 1.09, 95%CI 0.97-1.23). Exposure to campaigns and information regarding breast cancer screening, whether cancer patients are or not in around, perceived severity, perceived benefit, and perceived cost were factors that were not significantly associated with the intention to undergo mammography. Conclusion: It is necessary to develop tailored intervention strategies for women who have never undergone breast cancer screening on the basis of their demographic characteristics and factors that positively influence the intention to undergo mammography.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.2 no.1
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• pp.37-64
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• 2007

The purpose of this study is verifying which financial property of a venture company listed in KOSDAQ is a primary factor to determine Highly Successful company or Less Successful one. For sampling, I classified 405 venture companies, whose averages for 2005 of 2 standards are In the 30% high/low rank, as Highly Successful/Less Successful companies subject to the higher Operating Income to Total Assets and Return on Invested Capital (ROIC), the Highly Successful company. And I verified which variable is most important one to distinguish between Highly Successful companies and Less Successful ones among 24 financial ratios selected through preceding studies. For the analysis, I firstly extracted analogous variables by Stepwise Method and secondly carried out Multi variate Discriminant Analysis. The result mainly shows variables related to returns and stability similar to preceding studies. Especially, Operating Income to Total Assets reveals most reliable variable distinguishing between Highly Successful company and Less Successful one, whereas Current Ratio does not. When reliability of function formula of variables were compared with Operating Income to Total Assets standard and ROIC standard, there was almost no difference.

• Journal of Environmental Health Sciences
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• v.34 no.4
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• pp.300-310
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• 2008

In order to further determine the mass concentration and ion composition of size-segregated particulate matter (PM) during the non-Asian dust storm of spring, $PM_{2.5}$ (fine particle), $PM_{10-2.5}$ (coarse particle), and $PM_{over-10}$ (PM with an aerodynamic diameter larger than $10{\mu}m$) were collected using a MCI (multi-nozzle cascade impactor) sampler of a three-stage filter pack in the spring season of 2007 in the Iksan area. During the sampling period from 5 April to 21 April, a total of 34 samples for size-segregated PM were collected, and then measured for PM mass concentrations by gravimetric measurements and for water-soluble inorganic ion species by using ion chromatography. Average mass concentrations of $PM_{2.5}$, $PM_{10-2.5}$, $PM_{over-10}$ were $35.4{\pm}11.5{\mu}g/m^3$, $13.3{\pm}5.5{\mu}g/m^3$ and $9.5{\pm}4.7{\mu}g/m^3$, respectively. On average, $PM_{2.5}$ accounted for 74% of $PM_{10}$. Compared with the literature from other areas in Korea, the measured concentration of $PM_{2.5}$ were relatively high. Water-soluble inorganic ion fractions in $PM_{2.5}$, $PM_{10-2.5}$, and $PM_{over-10}$ were found to be 47.8%, 28.5%, and 14.7%, respectively. Among the water-soluble inorganic ion species, $SO_4^{2-}$, $NO_3^-$ and $NH_4^+$ were the main components in $PM_{2.5}$, while $NO_3^-$ dominantly existed in both $PM_{10-2.5}$ and $PM_{over-10}$. Non-seasalt $SO_4^{2-}$ (nss-$SO_4^{2-}$ and $NO_3^-$ were found to mainly exist as the neutralized chemical components of $(NH_4)_2SO_4$ and $NH_4NO_3$ in fine particles.

• Journal of Astronomy and Space Sciences
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• v.26 no.2
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• pp.229-236
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• 2009

KOorea Multi-purpose SATellite(KOMPSAT)-5 will be launched at 550km altitude in 2010. Accurate satellite position(20 cm) and velocity(0.03 cm/s) are required to treat highly precise Synthetic Aperture Radar(SAR) image processing. Ionosphere delay was eliminated using dual frequency GPS data and double differenced GPS measurement removed common clock errors of both GPS satellites and receiver. SAC-C carrier phase data with 0.1 Hz sampling rate was used to achieve precise orbit determination(POD) with ETRI GNSS Precise Orbit Determination(EGPOD) software, which was developed by ETRI. Dynamic model approach was used and satellite's position, velocity, and the coefficients of solar radiation pressure and drag were adjusted once per arc using Batch Least Square Estimator(BLSE) filter. Empirical accelerations for sinusoidal radial, along-track, and cross track terms were also estimated once per revolution for unmodeled dynamics. Additionally piece-wise constant acceleration for cross-track direction was estimated once per arc. The performance of POD was validated by comparing with JPL's Precise Orbit Ephemeris(POE).

• Journal of the Korean Society for Library and Information Science
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• v.52 no.2
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• pp.143-164
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• 2018

The purpose of this study was to investigate the relationship between public library use and the individual's personal value system. The personal value system was measured by Schwartz's (1992) Theory of Basic Human Values. The theory includes ten universal values, which can be categorized into four higher-order values: namely, self-transcendence vs. self-enhancement; and openness to change vs. conservation. The data were collected on the web from 1,000 Korean adults who were 18 years old or above using a quota sampling method with respect to the distributions of gender, age, and geographic locations of the general Korean adult population. The collected data were analyzed using multi-dimensional scaling method, t-tests, and multiple correlations. The results showed that the public library is more likely to be used by the individuals who value "openness to change" (representing self-direction and stimulation), and "self-enhancement"(representing achievement, power, hedonism/sensuous pleasure) than those who value "conservation" (representing safety, stability of society, conformity to rules, tradition) and "self-transcendence" (representing interest in other's well-being, and tolerance, welfare of humanity and community). The findings suggest that public library uses reflect the characteristics of major library services, such as reading and self-learning, which are very autonomous and individualistic in their nature. The findings are valuable in understanding the nature of the functions performed by the current Korean public libraries that are reflected in the personal values of Korean adult library users.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.8
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• pp.3452-3459
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• 2012

The purpose of this study was to analyze the relationships on participation on health education program toward skin care and the improvement of healthy life habit. The subject of the study was selected by multi-stage stratified cluster random sampling among the skin care education center to learn health education program toward skin care among women in the Seoul and Kyunggi area. The data were collected through a questionnaire adapted from Payne and Hahn's(1986) 'Understanding Your Health-A personal profile; Evaluating Your Health'. The pilot test was executed after the questionnaire was translated into Korean. The statistics employed the study were validity and reliability test, $x^2$ verification, frequency, ANOVA, multiple classification analysis, ANCOVA and Multiple Regression Analysis. The results that were derived from these processes were as follows: First, before and after on health education program toward skin care, the student's healthy life habit is partially changed. Second, the relationship the period of education program and the characteristic healthy life habit, long-term skin care education is positively affected sleeping habit, anti-stress treatment, exercise and nutrition. Third, the relationship on the frequency of education program and the characteristic healthy life habit, more frequently participation on skin care education is positively affected on healthy life habit and exercise.

• Nutrition Research and Practice
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• v.10 no.1
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• pp.56-66
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• 2016

BACKGROUND/OBJECTIVES: Despite successes recorded in combating iodine deficiency, more than 2 billion people are still at risk of iodine deficiency disorders. Rural landlocked and mountainous areas of developing countries are the hardest hit, hence the need to explore and advance novel strategies such as biofortification. SUBJECTS/METHODS: We evaluated adoption, purchase, and consumption of iodine biofortified vegetable legumes (IBVL) using the theory of protection motivations (PMT) integrated with an economic valuation technique. A total of 1,200 participants from three land-locked locations in East Africa were recruited via multi-stage cluster sampling, and data were collected using two, slightly distinct, questionnaires incorporating PMT constructs. The survey also elicited preferences for iodine biofortified foods when offered at a premium or discount. Determinants of protection motivations and preferences for iodine biofortified foods were assessed using path analysis modelling and two-limit Tobit regression, respectively. RESULTS: Knowledge of iodine, iodine-health link, salt iodization, and biofortification was very low, albeit lower at the household level. Iodine and biofortification were not recognized as nutrient and novel approaches, respectively. On the other hand, severity, fear, occupation, knowledge, iodine status, household composition, and self-efficacy predicted the intention to consume biofortified foods at the household level; only vulnerability, self-efficacy, and location were the most crucial elements at the school level. In addition, results demonstrated a positive willingness-to-pay a premium or acceptance of a lesser discount for biofortification. Furthermore, preference towards iodine biofortified foods was a function of protection motivations, severity, vulnerability, fear, response efficacy, response cost, knowledge, iodine status, gender, age. and household head. CONCLUSIONS: Results lend support for prevention of iodine deficiency in unprotected populations through biofortification; however 'threat' appraisal and socio-economic predictors are decisive in designing nutrition interventions and stimulating uptake of biofortification. In principle, the contribution is threefold: 1) Successful application of the integrated model to guide policy formulation; 2) Offer guidance to stakeholders to identify and tap niche markets; 3) stimulation of rural economic growth around school feeding programmes.

• Journal of the Korean Society of Child Welfare
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• no.54
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• pp.145-172
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• 2016

The purpose of this study was to examine whether parenting attitudes would have an effect on the developmental trajectories of school adjustment for adolescents in out-of-home care. Additionally, we hypothesized that this model would be different between boys and girls. In this study, we analyzed three waves of data collected from 341 adolescents living in residential facilities, group homes or foster homes by using cluster sampling methods. Growth-curve longitudinal analysis was conducted, and the results indicated that levels of school adjustment had increased from the 1st through the 3rd grade of middle school. Positive parenting attitudes had a positive impact on initial school adjustment and rate of change, whereas negative parenting attitudes had a negative impact only on the initial school adjustment. Second, multi-group analysis revealed that there were group differences between boys and girls in their initial school adjustment by positive parenting attitudes. Based on these results, this study discussed further suggestions to increase school adjustments for adolescents in out-of-home care.