• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.354-374
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• 2016

This study explored spatiotemporal variability of water quality in correspondence with hydrometeorological factors in the five stations of Paldang Reservoir located in the Han River during 4 years from May 2012 to December 2015. Variability of basic water quality factors were largely related with seasonal fluctuations of hydrology. Temperature stratification occurred in the deep dam station, and prolonged hypoxia was observed during the draught year. Nitrogen nutrients were increased with decreasing inflow in which changing pattern of $NH_4$ reversed to $NO_3$ by the effect of treated wastewater effluent. Phosphorus increase was manifest during the period of high inflow or severe drought. Chl-a variation was reversely related with both flow change and AGP(algal growth potential) variations. Our study demonstrated that water quality variability in Paldang Reservoir was largely attributed to both natural and operational changes of inflow and outflow (including water intake) based on major pollution source of the treated wastewater (total amount of $472{\times}10^3m^3d^{-1}$) entering to the water system from watershed. In the process of water quality variability, meteorological (e.g., flood, typhoon, abnormal rainfall, scorching heat of summer) and hydrological factors (inflow and discharge) were likely to work dynamically with nutrients pulse, dilution, absorption, concentration and sedimentation. We underline comprehensive limnological study related to hydro-meteorolology to understand short- and long-term water quality variability in river-type large reservoir and suggest the necessity of P-free wastewater treatment for the effective measure of reducing pollution level of Paldang drinking water resource.

• Journal of Animal Environmental Science
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• v.16 no.3
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• pp.237-244
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• 2010

Using a vertical composting system in layer farms, the composting process was characterized in terms of temperature variation, change of moisture contents, fertilizer ingredient and so on. In this study, two types of layer farms were examined. The layer manure was produced as 3,300 and 116,650 kg/day for Farm A and Farm B, respectively. Also, their average moisture contents were 74.4% (Farm A) and 65.6 % (Farm B). The inside temperature of composting in Farm A was varied in the range of 50 to $70^{\circ}C$, and moisture content of it decreased from 59.5% to 20.6% at the edge of vertical composting system. While in Farm B, composting temperature was fluctuated between 50 and $65^{\circ}C$ and moisture content declined from 34.0% to 13.4% at the end of vertical composting system. The fertilizer ingredients such as T-N, $P_2O_5$ and $K_2O$ were not significantly influenced by seasonal effect. Their values were changed in the range of 0.90% to 0.47% for T-N, 0.16% to 0.42% for $P_2O_5$, and 0.22% to 0.28 for $K_2O$, respectively. Also, OM/N ratio was varied from 36.8 to 84.4.

• The Korean Journal of Food And Nutrition
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• v.24 no.1
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• pp.124-131
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• 2011

We analyzed content and peptides in order to investigate the productivity from Cheonggookjang(fast-fermented soybean paste), fermenting it for 180 hours at $40^{\circ}C$. Results showed that pH was 7.07 at the start and became 7.41 in 24 hours, it eventually increased to 8.63 after 180 hours. Acidity was 0.2 in 12 hours, 0.5 in 12 hours, and then remained on 0.1 thereafter. Total sugar was 1.54 mg/$m\ell$ at the start, but it gradually decreased to 0.76 mg/$m\ell$ after the lapse of 48 hours, and 1.0 mg/$m\ell$ in 120 hours, and finally 0.8 mg/$m\ell$ in 180 hours. Reducing sugar was 0.14 mg/$m\ell$ at the start, and 0.88 mg/$m\ell$ after the lapse of 24 hours, 0.64 mg/$m\ell$ in 48 hours, 0.26 mg/$m\ell$ in 72 hours, and showed no definite change untill 180 hours. The amount of free amino acid was $0.19\;{\mu}M/\ell$ at the start, and $4.88\;{\mu}M/\ell$ after the lapse of 72 hours, $4.5\;{\mu}M/\ell$ in 120 hours, and then it rapidly decreased to $0.23\;{\mu}M/\ell$ after180 hours. Absorbance of soluble protein and peptide at 280 nm was 12.4 in 48 hours, 31.12 in 120 hours, and 31.12 in 180 hours. HPLC revealed that in the fermentation process, large molecular proteins are hydrolyzed into small peptides and amino acids, and after the lapse of 48 hours the pattern became almost the same. The protease activity of Cheonggookjang was 0.011 unit/$m\ell$ after the lapse of 36 hours and then it decreased. The result shows as Cheonggookjang started its deamination of amino acid in 100 hours, it is desirable to produce peptide within 100 hours of its fermentation.

• The Korean Nurse
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• v.31 no.3
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• pp.76-87
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• 1992

The purposes of study was: 1. To identify the direction and scope of research activities in Korean Nursing. 2. To discuss the unique problems present in Korea that warrant nursing research. 3. To delineate the factors that facilitate and/or hinder nursing research in Korea. This study was conducted at six colleges of nursing in Korea. The schools which were selected had doctoral programs at the time, the data were collected in 1990. Four of the schools were located in the metropolitan area of the capital city, Seoul, and two were in two other cities similar in size. The total population of the study was 283 nurses. The instrument for the research was the English version of Research Profile Questionnaire which was translated into Korean by the researchers and was validated in its translation by two professors. A pretest procedure was done before the data collection process. Of the population of 283, 210 subjects received the questionnaire and 150 subjects responded(71.4%). Excluding incomplete questionnaires, 141 questionnaires were utilized for data analysis. Data were analyzed using descriptive statistics. Responses to open-ended questions were content analyzed for themes and categories. Results of the study were as follows : Respondents currently , involved in nursing research numbered 108(76.6%), but 33(23.4%) did not have any research experience. The inexperienced respondenLs tended to be younger than the experienced subjects and most( 60.6%) were employed in hospitals, while 82.4 percent of the experienced nurses were employed in nursing schools. Among the respondents with research experience, 68.5 percent were involved in one to three projects and 31.5 percent were engaged in four or more projects. The experienced nurses indicated that nursing research in Korea is active. On the other hand, the responses of the inexperienced were that nursing research is not active. The most frequently selected research subjects were patients(76.9%, 83 respondents) followed by nurses, healthy persons and nursing students. The relatively high percentage of healthy persons as study subjects, could be explained as a concern of nurses for healthy persons as well as for ill patients. The aforememioned literature review showed a dramatic change in the kinds of study subjects; approximately 33 percent were patients but 25 percent were healthy subjects of various ages. The hospital was the prevailing research setting(67.6%) but at the same time various community settings were used. This is a changing phenomena in nursing research of Korea. Current research designed to build on previous studies amounted to 75 percent; about 39.8 percem were theory and hypothesis generated. Over 65 recommended additional research focusing on hypothesis-testing 0:' theory building. The previously quoted literature review found that only 4.0 percent of the study quescions were developed from a theoretical framework. The most frequently listed current major focus of nursmg research was stress and adaptation. Patients with cancer, pain, social support and care of the elderly were the next most frequently reported. These concerns may reflect problems associated with a technological and industrializing societyl. The most frequently identified problem was lack of clinical research. The need for replication research and research that contributes to the accumulation of nursing knowledge were found to be rare in Korean research. A need for theory testing and theory construction research was also identified. Although advanced statistical methods were often utilized in nursing research, the results were frequently considered by the interviewers not to be applicable in practice, and readers had difficulty in comprehending the findings. Even though the number of clinical nurses involved in research is increasing, it is still considered inadequate. Among 108 respondents, 83(76.9%) gave lack of time as a barrier to conducting nursing research. Over fifty percent of the respondents reported lack of funding or, personally, low confidence in research skills as barriers. The respondents offered 183 suggestions for future emphasis in nursing research. Among the 51 areas of emphasis, clinical research received the highest number and nursing intervention was next. The findings suggested that nursing research should be based on theory, be related to practice and relevant to the situation of a unique Korean culture.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.30 no.3
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• pp.42-56
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• 2012

This study was carried out to investigate the construction characteristics and the landscaping design skill for Wiyiam at Ongnyucheon(玉流川) in the rear garden of Changdeok Palace focusing on constructing technique, space composition and transformational process of the site. The results of this study were summarized as follows; First, Wiyiam of Ongnyucheon was constructed as garden ornament which was modified the huge bedrock into the shape of the mountain. The waterfall of Wiyiam was originally made of torrent which water flowed into the bottom, but it was reconstructed to take the effect of Inak(離落: the method to drop water from high place) by carving rock into square shape at the era of King Gojong(高宗). Second, main characteristics of Wiyiam appeared in Donggwoldo was the hill built up with a square pond and ground at the back of Wiyiam and the profound scenery of mountains and stream from the view of Wiyiam. Also, pavilions such as Soyojeong(逍遙亭), Cheongujeong and Taegeukjeong(太極亭) built in Ongnyucheon seemed to be constructed as the spots to appreciate the view and waterfall sound of Wiyiam. Also the spots were not bounded by the function of creating special water systems such as Cheongujeong pond and Taegeukjeong pond and showed the outstanding landscape design skill to make people feel unusual interest from each spot. On the other hand, this study considered that the evening scenery of Wiyiam, beautiful sound of falling water, unusual water system with beautiful plant materials were landscaped for the function of the psychological peace and stability to the appreciators. Lastly, the extreme change of space composition in Ongnyucheon was assumed as a strategy to improve the existing poor drain environment by confirming that the mountain stream and wall of Soyojeong were removed and drainage in both side of Soyojeong was installed in the 21th year of King Gojong's reign(1884).

• Journal of Distribution Science
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• v.4 no.2
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• pp.81-106
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• 2006

The value of Its visitors is very important factors on selection of a Spa & Resort. The first detailed purpose of this paper is to analyse the differences of select behaviors of a Spa & Resort according to the types of values of the visitors. The second aim is to conduct a research on the characters of select behaviors of the visitors. The third aim is to analyse the degree of satisfaction of the visitors, re-visitation and the intention of recommendation. The fourth purpose is to provide useful materials on analysis about the values of the visitors at various Spa & Resorts and to trigger dramatic effect of recuperation, relaxation with its visitor's needs met, the maximum of hotel's management profit at Spa & Resort's area and programs to activate the region's economy. Factor Analsis Routine of SPSS Windows Version 10.0 was applied to accomplish the issues of the study. The Applied analysis by research process are as follows; This paper applied Frequency analysis to figure out interviewee's demographic characters and various using types of the visitors, using their experience of visiting, Select influence, Visiting period, Accommodation they use, Accompanyist, Costs, Season, Transportation, The necessary time. This paper showed important correlation between the visitors' select attributes and behaviors after using it, between their personal value and behaviors after using it, between their individual value, motive of use and their select behavior of destinations. In accordance with it, Managers or developer of a Spa & Resort should make a plan after a sufficient review of the visitors' individual value. The visitor's value is changing continuously according to the change of spatial, occasional environment and should be assessed by those changes.

• Korean Journal of Dental Materials
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• v.45 no.4
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• pp.257-274
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• 2018

The purpose of this study was to evaluate the effect of acid-treatment conditions on the surface properties of the RBM (Resorbable Blast Media) treated titanium. Disk typed cp-titanium specimens were prepared and RBM treatments was performed with calcium phosphate ceramic powder. Acid solution was mixed using HCl, $H_2SO_4$ and deionized water with 4 different volume fraction. The RBM treated titanium was acid treated with different acid solutions at 3 different temperatures and for 3 different periods. After acid-treatments, samples were cleaned with 1 % Solujet solution for 30 min and deionized water for 30 min using ultrasonic cleanser, then dried in the electrical oven ($37^{\circ}C$). Weight of samples before and after acid-treatment were measured using electric balance. Surface roughness was estimated using a confocal laser scanning microscopy, crystal phase in the surface of sample was analyzed using X-ray diffractometer. Surface morphology and components were evaluated using Scanning Electron Microscope (SEM) with Energy Dispersive X-ray spectroscopy (EDX) and X-ray Photoemission Spectroscopy (XPS). Values of the weight changes and surface roughness were statistically analyzed using Tukey-multiple comparison test (p=0.05). Weight change after acid treatments were significantly increased with increasing the concentration of $H_2SO_4$ and temperature of acid-solution. Acid-treatment conditions (concentration of $H_2SO_4$, temperature and time) did not produce consistent effects on the surface roughness, it showed the scattered results. From XRD analysis, formation of titanium hydrides in the titanium surface were observed in all specimens treated with acid-solutions. From XPS analysis, thin titanium oxide layer in the acid-treated specimens could be evaluated. Acid solution with $90^{\circ}C$ showed the strong effect on the titanium surface, it should be treated with caution to avoid the over-etching process.

• Journal of the Geological Society of Korea
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• v.54 no.5
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• pp.477-488
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• 2018

Fluid muds commonly occur in estuarine environments, but their ancient examples have rarely been studied in terms of depositional characteristics and processes. Cores of estuarine channel deposits of the Early Cretaceous McMurray Formation, Alberta, Canada show various mudstone layers that possess depositional characteristics of high clay-concentration flows. These mudstone layers are examined in detail through microscopic observation of thin sections and classified into three microfacies (<1 to 25 mm thick) on the basis of sedimentary texture and structures. Structureless mudstone (Microfacies 1) consists mainly of clay particles and contains randomly dispersed coarser grains (coarse silt to fine sand). This microfacies is interpreted as being deposited by cohesive mud flows, i.e., fluid muds, which possessed sufficient strength to support suspended coarser grains (quasi-laminar plug flow). Silt-streaked mudstone (Microfacies 2) mainly comprises mudstone with dispersed coarse grains and includes very thin, discontinuous silt streaks of coarse-silt to very-fine-sand grains. The texture similar to Microfacies 1 indicates that Microfacies 2 was also deposited by cohesive fluid muds. The silt streaks are, however, suggestive of the presence of intermittent weak turbulence under the plug (upper transitional plug flow). Heterolithic laminated mudstone (Microfacies 3) is characterized by alternation of relatively thick silt laminae and much thinner clay laminae. It is either parallel-laminated or low-angle cross-laminated, occasionally showing low-amplitude ripple forms. The heterolithic laminae are interpreted as the results of shear sorting in the basal turbulent zone under a cohesive plug. They may represent low-amplitude bed-waves formed under lower transitional plug flows. These three microfacies reflect a range of flow phases of fluid muds, which change with flow velocities and suspended mud concentrations. The results of this study provide important knowledge to recognize fluid-mud deposits in ancient sequences and to better understand depositional processes of mudstones.

• Korean Journal of Remote Sensing
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• v.26 no.2
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• pp.251-262
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• 2010

In order to provide quantitative control of the standard products of Geostationary Ocean Color Imager (GOCI), on-board radiometric correction, atmospheric correction, and bio-optical algorithm are obtained continuously by comprehensive and consistent calibration and validation procedures. The calibration/validation for radiometric, atmospheric, and bio-optical data of GOCI uses temperature, salinity, ocean optics, fluorescence, and turbidity data sets from buoy and platform systems, and periodic oceanic environmental data. For calibration and validation of GOCI, we compared radiometric data between in-situ measurement and HyperSAS data installed in the Ieodo ocean research station, and between HyperSAS and SeaWiFS radiance. HyperSAS data were slightly different in in-situ radiance and irradiance, but they did not have spectral shift in absorption bands. Although all radiance bands measured between HyperSAS and SeaWiFS had an average 25% error, the 11% absolute error was relatively lower when atmospheric correction bands were omitted. This error is related to the SeaWiFS standard atmospheric correction process. We have to consider and improve this error rate for calibration and validation of GOCI. A reference target site around Dokdo Island was used for studying calibration and validation of GOCI. In-situ ocean- and bio-optical data were collected during August and October, 2009. Reflectance spectra around Dokdo Island showed optical characteristic of Case-1 Water. Absorption spectra of chlorophyll, suspended matter, and dissolved organic matter also showed their spectral characteristics. MODIS Aqua-derived chlorophyll-a concentration was well correlated with in-situ fluorometer value, which installed in Dokdo buoy. As we strive to solv the problems of radiometric, atmospheric, and bio-optical correction, it is important to be able to progress and improve the future quality of calibration and validation of GOCI.

• Korean Journal of Remote Sensing
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• v.21 no.6
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• pp.445-456
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• 2005

The land surface parameters should be determined with sufficient accuracy, because these play an important role in climate change near the ground. As the surface reflectance presents strong anisotropy, off-nadir viewing results a strong dependency of observations on the Sun - target - sensor geometry. They contribute to the random noise which is produced by surface angular effects. The principal objective of the study is to provide a database of accurate surface reflectance eliminated the angular effects from MODIS 250m reflective channel data over Korea. The MODIS (Moderate Resolution Imaging Spectroradiometer) sensor has provided visible and near infrared channel reflectance at 250m resolution on a daily basis. The successive analytic processing steps were firstly performed on a per-pixel basis to remove cloudy pixels. And for the geometric distortion, the correction process were performed by the nearest neighbor resampling using 2nd-order polynomial obtained from the geolocation information of MODIS Data set. In order to correct the surface anisotropy effects, this paper attempted the semiempirical kernel-driven Bi- directional Reflectance Distribution Function(BRDF) model. The algorithm yields an inversion of the kernel-driven model to the angular components, such as viewing zenith angle, solar zenith angle, viewing azimuth angle, solar azimuth angle from reflectance observed by satellite. First we consider sets of the model observations comprised with a 31-day period to perform the BRDF model. In the next step, Nadir view reflectance normalization is carried out through the modification of the angular components, separated by BRDF model for each spectral band and each pixel. Modeled reflectance values show a good agreement with measured reflectance values and their RMSE(Root Mean Square Error) was totally about 0.01(maximum=0.03). Finally, we provide a normalized surface reflectance database consisted of 36 images for 2001 over Korea.