• Journal of the Korean GEO-environmental Society
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• v.17 no.9
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• pp.37-45
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• 2016

This study analyzes the environmental and durability problems of traditional (LW) grouting method. And the proposed method was compared to the others effects by analyzing the in-situ applicability and effect of performance of the method using the silica sol. This study analyzed the eco-friendly, effects of high strength silica sol through laboratory tests. The effects of the construction process were identified through the field tests. The compressive strength was increased by 1.3 times compared to the LW method and the shrinkage is 3~8 times less than that of LW method with water glass. No toxicity, which could affect soil contamination. In particular, it was confirmed that the Toxicity fish also survived with little pH change in the concentration tank. Also it confirmed the construction effects through field test. Field tests are a standard penetration test, permeability test, LLT, BST. Permeability was reduced to $1{\times}10^{-5{\sim}-6}cm/sec$.

• Korean Journal of Adult Nursing
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• v.12 no.4
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• pp.690-705
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• 2000

This ethnography was based on Kleinman's explanatory model of a health care system. It is conducted to make thick discription of illness conception of the elderly in a sociocultural context. The basic assumptions were as follows. 1) A health care system is a cultural system, and as with any other cultural system, it is a system of symbolic meanings anchored in a particular arrangement of social institutions and patterns of interpersonal relationships; 2) In all societies health care activities are more or less interrelated. Therefore, they need to be in a holistic manner as socially organized responses to disease that constitute a special cultural system; health care system; 3) Health and illness experiences are the natural process of disease. Individuals who recognized a for state of health, their family, neighbors, and communities define the state, search for causes of the health problems, and response to it. According by, they proceed to search for healing stratagies. So, understanding of the illness experience is the starting point for health care. The study participants were 12 elders aged 60 or more. The fieldwork was conducted in an agricultural clan village of Namwon city. The data collection and analysis were cyclic, from descriptive observation, domain analysis, focused observation, taxanomic analysis, selected observation, componential analysis, and finally cultural themes were all analysed. Proxemic and text analysis techniques were used according to the characteristics of the data. The data of sociocultural context and descriptive data were collected from 1990 to 1992. Informations on illness concepts were collected during 1994 using focused observation. Data confirming and contrast observations were conducted from 1997 and 1999. Illness concepts of the elderly were taxonomized supernatural cause, non-supernatural cause, immediate cause, and ultimate cause. The supernatural ones were ancestors, god of home, god of village, and ghost such as 'sal(evil force of dead man)' and 'gagqui(ghost of begger)'. The non-supernatural ones were Ki, natural phenomenones, natural objects, foods, human and human behaviors. Immediate ones were insufficiency and overflows, discretion and consolidation, disorder and out of order, cloudness and contamination, and fluctuation and stagnation of supernatural cause and non-supernatural ones. Ultimate causes were intrusion and loss of supernatural and nonsupernatural ones. The cultural themes of illness concepts of the elderly are: 1) illness concepts are not based on causality principle, but on reciprocal principle; 2) illness concepts are affected by social level and charicteristics of the patients; 3) the causes of disease are recognized as imposed both positive and negative effects on health based on interpretation of the indiviuals; 4) illness concepts reflects on principles of everyday life of the society members such as hierachial structure and group cohesiveness; 5) illness concepts are ruled on principle of reciprocity and spread; 6) illness concepts are interrelated with physical environment of the participants. It can be concluded that the illness concepts of the elderly in a traditional clan village are a component of health care system as a cultural system based on these results. The these results can be a useful basis for gerontological nursing practice and education.

• Journal of the Institute of Convergence Signal Processing
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• v.4 no.1
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• pp.15-26
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• 2003

Ultrasonic inspection methods are widely used for detecting flaws in materials. The signal analysis step plays a crucial part in the data interpretation process. A number of signal processing methods have been proposed to classify ultrasonic flaw signals. One of the more popular methods involves the extraction of an appropriate set of features followed by the use of a neural network for the classification of the signals in the feature space. This paper describes an alternative approach which uses the least mean square (LMS) method and expectation maximization (EM) algorithm with the model based deconvolution which is employed for classifying nondestructive evaluation (NDE) signals from steam generator tubes in a nuclear power plant. The signals due to cracks and deposits are not significantly different. These signals must be discriminated to prevent from happening a huge disaster such as contamination of water or explosion. A model based deconvolution has been described to facilitate comparison of classification results. The method uses the space alternating generalized expectation maximization (SAGE) algorithm In conjunction with the Newton-Raphson method which uses the Hessian parameter resulting in fast convergence to estimate the time of flight and the distance between the tube wall and the ultrasonic sensor Results using these schemes for the classification of ultrasonic signals from cracks and deposits within steam generator tubes are presented and showed a reasonable performances.

• Journal of Conservation Science
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• v.27 no.4
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• pp.345-356
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• 2011

To remove metal stains of the ceramics, chemical cleaning is essential case by case. This study investigated the removal characteristics of iron stains by oxalic acid and citric acid including their application methods of soaking and poultice. The soaking method in cleaning agents showed removal process by color difference and released iron contents from iron stains on ceramics. Iron stains were removed successfully from ceramics, which soaked in oxalic acid for 60 hours. However, it is recommendable to soak in 0.25M oxalic acid for one to three hours because most iron stains were disappeared in 3 hours soaking. Citric acid is less effective than oxalic acid in removing iron stains because of heavy molecular weight and low acidity. Poultices (bentonite, sepiolite, activated carbon fiber and celite) with oxalic acid were applied on contaminated ceramics. After ten hours, iron stains on ceramics were removed successfully by poultice. Among them, bentonite and sepiolite have better application. Therefore, sepiolite with 0.25M oxalic acid was applied on the iron stains of whiteware and celadon from Ma Island, and then stains were removed. However, it is judged that the application methods can be varied according to the form and depth of contaminant. In addition, the residues of poultice on the ceramics will be considered for preventing contamination.

• Journal of Korean Society of Environmental Engineers
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• v.37 no.4
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• pp.204-209
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• 2015

The effluent limit of nickel from electroplating wastewater has been strengthened from 5 mg/L to 3 mg/L from 2014. However, currently applied treatment process for nickel plating wastewater is unable to meet the effluent limit, most of the treatment concept conducted by treatment plant is dilution with other metal bearing wastewater. This can cause very significant impact to the environment of nickel contamination. With this connection, the feasibility test has been conducted with the use of electrolysis by using sacrificial electrodes. Experiments were conducted in synthetic and electroless nickel plating wastewater. Optimal condition of current density, pH were derived from the synthetic wastewater. It was found that the removal efficiency of nickel exceeded 94% at the operation condition of at pH 9 and the current density of $1{\sim}2mA/cm^2$. At this conditions, the iron sludge was generated very low amount. However, it was unsuccessful to meet the effluent limit by applying these treatment conditions to the real electroplating wastewater. This can be explained due to the matrix effect of other metals and anions contained real electroplating wastewater. From the result of further study, the optimal conditions for the real wastewater treatment were found out to be at pH 9, current density $6{\sim}7mA/cm^2$, for 5 minutes of operating time. At these conditions, 88% removal of nickel was achieved, which results the residual nickel concentration was below 3 mg/L.

• Journal of Korean Society of Environmental Engineers
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• v.29 no.4
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• pp.438-443
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• 2007

This study was done to investigate perchlorate contamination in Nakdong river. The perchlorate was detected in Nakdong river and ranged from ND to $82.1{\mu}g/L$. The highest concentration was observed in Wheguan. The perchlorate concentration was decreased with the down stream of Nakdong river. Three different virgin activated carbons made of each coal(Calgon), coconut(Samchully) and wood(Picabiol) based activated carbon(AC) were tested for an adsorption performance of perchlorate in a continuous adsorption column. Breakthrough behavior was investigated that the breakthrough points of coal, coconut and wood based AC as 2,300 bed volumn(BV), 719 BV and 288 BV respectively. Adsorption capacity(X/M) of real, coconut and wood based AC was observed. The experimental results of adsorption capacity showed that coal based AC was highest$(768.2{\mu}g/g)$, coconut based AC was intermediate$(299{\mu}g/g)$ and wood based AC was lowest$(99.2{\mu}g/g)$. Moreover, carbon usage rates(CURs) for coal, coconut and wood based AC had been shown as 0.71 g/day, 2.16 g/day and 3.45 g/day respectively. The constant characteristic of the system, k of coal, coconut and wood based ACs were found to be 307.2, 102.5 and 94.2, respectively.

• Economic and Environmental Geology
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• v.41 no.6
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• pp.673-683
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• 2008

As-rich alluvial groundwaters occurring in the agricultural area of Mankyeong River watershed were geochemically studied. 15 out of 29 investigated wells (52%) showed As levels exceeding the WHO drinking water standard ($10{\mu}g/L$). Their chemistry is characterized by low Eh levels, low $NO_3$ and $SO_4$ concentrations, and high pH, alkalinity, Fe, $NH_4$, and $PO_4$ levels. This suggests that arsenic is enriched by the reductive dissolution of As-bearing Fe-/Mn-(hydro)oxides, the commonest process in Bangladesh and West Bengal of India, of which groundwaters are severely contaminated by As. It was also revealed that As concentrations in the area are strongly regulated by the presence of agrochemicals such as $NO_3$ and $SO_4$.

• Korean journal of food and cookery science
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• v.28 no.5
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• pp.515-530
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• 2012

This research aims to audit foodservice sanitation management practices and to assess microbiological quality of foods and their food contact environments in kindergartens. Sanitation auditing was conducted in 10 kindergartens in Seoul, Gyeonggi, and Incheon areas to assess the levels of safety practices. Results revealed that the surveyed kindergartens scored 41.4 out of 100 points, on average. The average scores of each category were 6.4/11 (58.1%) for facilities sanitation, 4.2/12 (35.0%) for equipment sanitation, 2.4/10 (24.0%) for personal hygiene, 5.1/10 (51.0%) for food ingredients management, 6.0/17 (35.3%) for production process, 5.4/10 (54.0%) for environmental sanitation, 2.0/6 (33.3%) for kitchen utensils sanitation, and 2.2/6 (96.7%) for safety management. Microbiological quality of raw, prepared foods, personal sanitation (hands), environmental sanitation, and drinking water were assessed. Total plate counts (TPC) of the following menus exceeded the critical limit: seasoned leek (5 log CFU/g), cucumber (5.0 log CFU/g), panbroiled fish paste (TNTC at $10^4$), tangpyeongchae (5.3 log CFU/g), egg rolls (6.1 log CFU/g), panbroiled sausage (TNTC at $10^4$), and soft tofu pot stew (TNTC at $10^4$). Coliform which exceeded the standard limit were detected from seasoned leek (2 log CFU/g), cucumber (2.5 log CFU/g), panbroiled fish paste (2.0 log CFU/g), egg roll (3.8 log CFU/g), tangpyeongchae (4.0 log CFU/g), panbroiled sausage (2.3 log CFU/g), and soft tofu pot stew (3.7 log CFU/g). For seasoned foods (muchim), S. aureus ranged 2.2~2.9 log CFU/g. In food workers' hands, microbial profiles ranged 3.8~7.9 log CFU/hand for TPC, ND~4.5 log CFU/hand for coliforms, ND~4.7 log CFU/hand for S. aureus, and ND~5.3 log CFU/hand for Enterobacteriaceae. Microbiological profiles of food contact surface of knives, cutting boards, dish-clothes, and trays showed possibilities of cross-contamination. General bacteria were 2.1~4.5 logCFU/ml in 4 purified water samples and E. coli were found in the kitchen of one kindergarten. These results suggested that environmental sanitation management practices need more strict improvement: effective sanitation education methods and practices were strongly required, and more strict sanitation management for cooking utensils and equipment were required.

• Korean Journal of Soil Science and Fertilizer
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• v.41 no.3
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• pp.228-234
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• 2008

The purpose of this study was to predict environmental distribution of anthracene, benzene, benzo[a]pyrene, 1-methylphenanthrene and phenanthrene in a four phase biopile system - air, water, soil and non aqueous phase liquid (NAPL) phase using level I fugacity model. Soil samples used for this study were collected from three sites in the United Kingdom which were historically contaminated with petroleum hydrocarbons. The level I fugacities (f) for the five contaminants were markedly different, however, the fugacities of each contaminant in three soil samples did not show significant difference. NAPL and soil were the dominant phases for all five contaminants. Results of this study indicated that difference in percentage of organic carbon strongly influenced the partitioning behavior of the cntaminants. The presence of benzene calls for an urgent need for risk-based management of air and water phase. Whereas insignificant amount of chemicals leached in the water phase for other organic contaminants showing greatly reduced potential of groundwater contamination. Furthermore, this study helped us to confirm the association of risk critical contaminants with the residual saturation in treated soils. They also can be used to emphasize the importance of accounting for the partitioning behavior of both NAPL and soil phases in the process of the risk assessment of the sites contaminated with petroleum hydrocarbons.

• Journal of the Korean Society for Nondestructive Testing
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• v.25 no.1
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• pp.27-35
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• 2005

Ultrasonic inspection methods are widely used for detecting flaws in materials. The signal analysis step plays a crucial part in the data interpretation process. A number of signal processing methods have been proposed to classify ultrasonic flaw signals. One of the more popular methods involves the extraction of an appropriate set of features followed by the use of a neural network for the classification of the signals in the feature spare. This paper describes an alternative approach which uses the least mean square (LMS) method and exportation maximization (EM) algorithm with the model based deconvolution which is employed for classifying nondestructive evaluation (NDE) signals from steam generator tubes in a nuclear power plant. The signals due to cracks and deposits are not significantly different. These signals must be discriminated to prevent from happening a huge disaster such as contamination of water or explosion. A model based deconvolution has been described to facilitate comparison of classification results. The method uses the space alternating generalized expectation maximiBation (SAGE) algorithm ill conjunction with the Newton-Raphson method which uses the Hessian parameter resulting in fast convergence to estimate the time of flight and the distance between the tube wall and the ultrasonic sensor. Results using these schemes for the classification of ultrasonic signals from cracks and deposits within steam generator tubes are presented and showed a reasonable performances.