• Progress in Medical Physics
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• v.21 no.2
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• pp.192-200
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• 2010

Cyberknife with small field size is more difficult and complex for dosimetry compared with conventional radiotherapy due to electronic disequilibrium, steep dose gradients and spectrum change of photons and electrons. The purpose of this study demonstrate the usefulness of Geant4 as verification tool of measurement dose for delivering accurate dose by comparing measurement data using the diode detector with results by Geant4 simulation. The development of Monte Carlo Model for Cyberknife was done through the two-step process. In the first step, the treatment head was simulated and Bremsstrahlung spectrum was calculated. Secondly, percent depth dose (PDD) was calculated for six cones with different size, i.e., 5 mm, 10 mm, 20 mm, 30 mm, 50 mm and 60 mm in the model of water phantom. The relative output factor was calculated about 12 fields from 5 mm to 60 mm and then it compared with measurement data by the diode detector. The beam profiles and depth profiles were calculated about different six cones and about each depth of 1.5 cm, 10 cm and 20 cm, respectively. The results about PDD were shown the error the less than 2% which means acceptable in clinical setting. For comparison of relative output factors, the difference was less than 3% in the cones lager than 7.5 mm. However, there was the difference of 6.91% in the 5 mm cone. Although beam profiles were shown the difference less than 2% in the cones larger than 20 mm, there was the error less than 3.5% in the cones smaller than 20 mm. From results, we could demonstrate the usefulness of Geant4 as dose verification tool.

• Korean Journal of Environment and Ecology
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• v.26 no.4
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• pp.498-511
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• 2012

Mountainous wetland have many species such as II grade endangered species of wild flora and fauna(Drosera rotundifolia) and environmental indicator species(Utricularia racemosa, Habenaria linearifolia, Parnassia palustris, Molinia japonica, etc.). Accordingly, the mountainous wetlands is very important. However, most mountainous wetlands will disappear by natural or artificial aridness processes. Thus, it needs to manage mountainous wetland for protecting from aridness. This study has found out the wetland status of the environmental ecology and aridness processes moreover, it has suggested ways of improving wetland conservation plan and wetland aridness management plan. According to the results of topography structure survey, Hwaeom wetland's altitude is ranged within 750~810m(87.4%), and slope is less than $10^{\circ}$. There was ideally suited mountainous wetland. However, the water supply(1.6 meters depth and 0.8 meters wide) was built on under the wetland. For that reason, there was concerned about the aridness processes by sweeping away peat layer and dropping the water level. The distribution area of hygrophyte was narrowed to 6.7% whereas, woody plants and xerophytic plants was achieved a dominant position. If it leaves the situation as it is, the mountainous wetland will be developed next succession as forest ecosystem. Therefore, in order to sustain the mountainous wetland from aridness, it is set to the base direction of conservation and management as main schemes. Moreover, we have suggested that setting the vegetation conservation and management area which considering a ecological vegetation characteristics, managing the ecotone vegetation, setting the buffer zone for protection of ecological core areas, protecting the mountainous wetland indicator species and designating the management vegetation. In conclusion, in order to sustain and maintain a soundly wetland ecosystem, it needs to several management of wetlands damage factors. 1) suppression of the excessive groundwater to basin, 2) stabilization of wetland via hydrologic storage, 3) suppression of changing and transforming wetland into forest by succession via management of xerophytic plants.

• Journal of Korean Academy of Nursing
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• v.30 no.5
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• pp.1230-1242
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• 2000

The purpose of this research was to uncover the expertise of ICU nursing in Korea, and to describe nurses' practice based on the degree of skill acquisition. A total of 18 ICU nurses participated in the study. The data was collected through individual in-depth interviews and it was managed using the NUDIST 4.0 software program. The data was analyzed using interpretive phenomenology suggested by Benner. Four properties of expertise of ICU nursing were identified. These are 1) concern and love toward patients; 2) knowledge; 3) skill, and 4) abilities in interpersonal relationships. And the characterisitcs of four levels of skill acquisition, that is advanced beginner, competent, proficient, and expert, were described with exemplars. The results of this study might help nurse researchers clarify and elaborate on the concept of expertise in ICU nursing, and enable them to understand how the process of skill acquisition occurs in the ICU setting. They might also help nurse managers establish educational goals for ICU nursing for student or novice nurses.

• Korean Journal of Community Nutrition
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• v.25 no.3
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• pp.189-203
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• 2020

Objectives: This study was performed to identify the current barriers of obesity management for children using Community Child Care Centers and their caregivers (parents and teachers working in the Centers). Further, this study explored the possibility of utilizing a mobile phone application for tailored obesity prevention and management programs to overcome the current difficulties associated with children's obesity management. Methods: The qualitative data were collected through in-depth interviews with 20 obese and overweight children or children who wanted to participate in this study using Community Child Care Centers, 12 teachers working at the Centers, and a focus group interview with five parents of children using the Centers. Data were analyzed with a thematic approach categorizing themes and sub-themes based on the transcripts. Results: The current barriers of obesity management of obese and overweight children using Community Child Care Centers were lack of self-directed motivation regarding obesity management (chronic obesity-induced lifestyles and reduced self-confidence due to stigma) and lack of support from households and Community Child Care Centers (latchkey child, inconsistency in dietary guidance between the Center and household, repetitive pressure to eat, and absence of regular nutrition education). Mobile phone applications may have potential to overcome the current barriers by providing handy and interesting obesity management based on visual media (real-time tracking of lifestyles using behavior records and social support using gamification), environmental support (supplementation of parental care and network-based education between the Community Child Care Center and household), and individualized intervention (encouragement of tailored and gradual changes in eating habits and tailored goal setting). It is predicted that the real-time mobile phone program will provide information for improving nutritional knowledge and behavioral skills as well as lead to sustainable children's coping strategies regarding obesity management. In addition, it is expected that environmental factors may be improved by network-based education between the Community Child Care Centers and households using the characteristics of mobile phones, which are free from space and time constraints. Conclusions: The tailored education program for children using Community Child Care Centers based on mobile phones may prevent and reduce childhood obesity by overcoming the current barriers of obesity management for children, providing environmental and individualized support to promote healthy lifestyles and quality of life in the future.

• The Journal of Internal Korean Medicine
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• v.38 no.2
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• pp.201-216
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• 2017

Objective: This research aimed to understand patients' perceptions of Korean medicine treatment for osteoporosis in a clinical trial setting. Methods: Ten patients participating in a clinical trial of a herbal medicine drug for osteoporosis were invited to an interview. Data were collected by in-depth interviews and patient observations. This qualitative study adopted the case study research method, and within-case and cross-case analyses were conducted. Results: A model of the patients' osteoporosis management planning was derived from the study. The results showed that the patients' perceptions of osteoporosis were derived from their knowledge and experience during diagnosis and treatment of the condition. Two groups of patients were recognized: those who overlooked the importance of osteoporosis and those who recognized the importance of osteoporosis. Before making treatment decisions about osteoporosis, the patients evaluated the treatment options and weighed the advantages and disadvantages of each option. When evaluating their treatment, the patients combined their knowledge and experience of Korean and western medicine treatments. Their experience of participating in the clinical trial influenced the management planning of osteoporosis. Two major reasons for low compliance with osteoporosis treatment were ignorance of the disease and insufficient information provided by doctors. Conclusion: The results of this qualitative study pointed to four strategies that could be employed to improve accessibility to Korean medicine treatment for osteoporosis: the dissemination of comprehensive information on osteoporosis in the clinic and mass media, promotion of Korean medicine therapies for osteoporosis, management of clinical trial participants, and insurance coverage for Korean medicine.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.17 no.6
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• pp.192-198
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• 2016

The purpose of this study was to determine the relationship between the brand and awareness of the brand image relationship in a catering company in Gwangju quality(trust, satisfaction). Twenty adults aged 20 years or older residing in Gwangju were surveyed after setting a hypothesis as a convenience sampling method in order to achieve the research objectives via extraction of the sample survey and empirical analysis. Customers using the brand image of catering companies in a relationship significantly affected the quality of the relationship (trust) forming symbolic images, but the images that were empirically related significantly to the trust did not form a significant relationship for trust. Brand image quality significantly impacted the relationship(satisfaction) that is the symbolic image of relations forms a significant relationship between satisfaction. Empirically, however, the image did not form a significant relationship for satisfaction. Brand recognition is significant in relationship quality(trust) and a significant relationship brand recognition, as it has formed a significant relationship on trust. Brand recognition is the quality of the catering companies using the customer significant effect on the relationship (satisfaction) relationship of brand recognition was formed a significant relationship satisfaction. As a result, the catering company's brand image, brand perception and empirical validation suggested a relationship between the quality of the relationship that provided very significant implications in this regard. In the future, overcoming the limitations of this study will necessitate conducting a more in-depth and detailed study.

• Journal of Animal Science and Technology
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• v.53 no.3
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• pp.227-235
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• 2011

A total of 96 crossbred weanling barrows aged 21 days were randomly allocated to 32 pens of a new nursery to investigate the effects of antibiotics, phytogenics, and probiotics on intestinal growth and development. The animals were fed a set of three-phase basal diets containing 0.3% zinc oxide (CON) or the basal diets supplemented with 353 ppm of a combination of tiamulin, neomycin, chlortetracycline, and oxytetracycline (ANTI), 75 ppm triterpenoid saponin plus 150 ppm mixed saccharides (HERB; Sacchapin$^{(R)}$), or $1{\times}10^7$ brewer's yeasts plus $8{\times}10^7$ spores of each of Bacillus licheniformis and Bacillus subtilis per kilogram feed (PROBIO; Yeasture Plus 2B$^{(R)}$) for five weeks. Thirty-two pigs representing as many pens were slaughtered at the end of the feeding trial, after which morphological measures and digestive enzyme activities of intestinal mucosa were determined. Weight gain and gain:feed of the pigs were not affected by the dietary treatments (TRT) during the overall feeding trial. Total intestinal length was greater in PROBIO than in ANTI (P<0.05). Wet mucosa weight of the duodenum was not affected by TRT. However, jejunal mucosa weight was greater in PROBIO than in any other group sum of mucosa weights of the duodenum and jejunum was greater (P<0.05) in PROBIO than in ANTI and HERB. The height and width of duodenal villus were not affected by TRT, but crypt depth decreased (P<0.05) in response to HERB and PROBIO vs CON. Specific activities of alkaline phosphatase, sucrase, maltase, lactase, and leucine aminopeptidase in the duodenum and jejunum were not changed by TRT. In conclusion, results suggest that the present dietary treatments have no effects on growth performance of weanling pigs and that of PROBIO enhances intestinal growth and development under a clean experimental setting.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.31 no.4
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• pp.362-371
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• 1995

This study describes with the sinking behaviour for the purse seine. The experiment was carried out using three model purse seines of knotless netting. The nettings were woven in same leg length(10.5mm) of polypropylene 170 denier, polyamide 210 denier and polyester 250 denier two thread ply twine, each of the seines were named PP seine, PA seine and PES seine. Dimension of Purse seine models were 420cm for corkline and 85cm for seine depth, each models rigged 65.8g, 50.6g and 35.8g(weight in water) of lead for a leadline, seine models will have the same weight in water. Experiments carried out in the observation channel in a flume tank under still water conditions. Sinking motion was recorded by the one set of TV-camera for VTR, and reading coordinate carried out by the video digitization system. The results obtained were as follows: 1) Netting bundle for PP seine was existence on the surface of the water, spread out a netting by sinking force of sinkers. 2) Netting bundle for PES seine was existence in the middle of corkline and leadline. 3) Average sinking speed of seine margin was fastest for 10.7cm/s of PP seine, followed by 9.7cm/s of PA and 9.2cm/s of PES seines. 4) In all seines, the force of horizontal movement for the seine setting was values of ranged in disregard.

• Proceedings of the KSEEG Conference
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• 2002.06a
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• pp.81-100
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• 2002

While most of regulatory communities in abroad recognize ' 'natural attenuation " to include degradation, dispersion, dilution, sorption (including precipitation and transformation), and volatilization as governing Processes, regulators prefer "degradation" because this mechanism destroys the contaminant of concern. Unfortunately, true degradation only applies to organic contaminants and short- lived radionuclides, and leaves most metals and long-lived radionuclides. The natural attenuation Processes may reduce the potential risk Posed by site contaminants in three ways: (i)contaminants could be converted to a less toxic form througy destructive processes such as biodegradation or abiotic transformations; (ii) potential exposure levels may be reduced by lowering concentrations (dilution and dispersion); and (iii) contaminant mobility and bioavailability may be reduced by sorption to geomedia. In this review, authors will focus will focul on "sorption" among the natural attenuation processes of hazardous inorganic contaminants including radionuclides. Note though that sorption and transformation processes of inorganic contaminants in the natural setting could be influenced by biotic activities but our discussion would limit only to geochemical reactions involved in the natural attenuation. All of the geochemical reactions have been studied in-depth by numerous researchers for many years to understand "retardation" process of contaminants in the geomedia. The most common approach for estimating retardation is the determination of distrubution coefficiendts ($K_{d}$) of contaminants using parametric or mechanistic models. As typocally used in fate and contaminant transport calculations such as predictive models of the natural attenuation, the $K_{d}$ is defined as the ratio of the contaminant concentration in the surrounding aqueous solution when the system is at equilibrium. Unfortunately, generic or default $K_{d}$ values can result in significant error when used to predict contaminant migration rate and to select a site remediation alternative. Thus, to input the best $K_{d}$ value in the contaminant transport model, it is essential that important geochemical processes affecting the transport should be identified and understood. Precipitation/dissolution and adsorption/desorption are considered the most important geochemical processes affecting the interaction of inorganic and radionuclide contaminants with geomedia at the near and far field, respectively. Most of contaminants to be discussed in this presentation are relatively immobile, i.e., have very high $K_{d}$ values under natural geochemical environments. Unfortunately, the obvious containment in a source area may not be good enough to qualify as monitored natural attenuation site unless owner demonstrate the efficacy if institutional controls that were put in place to protect potential receptors. In this view, natural attenuation as a remedial alternative for some of sites contaminated by hazardous-inorganic components is regulatory and public acceptance issues rather than scientific issue.

• Journal of the Korean earth science society
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• v.34 no.6
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• pp.575-587
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• 2013

DC electrical and electromagnetic survey was applied to evaluate the reserve of an iron mine site. We analyzed the borehole cores and the cores sampled from outcrops in order to decide which geophysical method was efficient for the evaluation of iron mine site and to understand the geological setting around the target area. Based on the core tests for specific weight, density, porosity, resistivity and P-wave velocity, showing that the magnetite could be distinguishable by the electrical property, we decided to conduct the electrical survey to investigate the irone mine site. According to previous studies, the DC electrical survey was known to have various arrays with high resolutions effective to the survey of the iron mine site. However it was also known that the skin depth is too shallow to grasp the deep structure of iron mine. To compensate the weakness of the DC electrical method, we applied the MagnetoTelluric (MT) survey. In addition, a Controlled Source MT (CSMT) method was also applied to make up the shortcoming of MT method which is weak for shallow targets. From the DC electrical and MT survey, we found a new low resistivity zone, which is believed to be a magnetite reserve beneath the old abandoned mine. Therefore, this study was confirmed for additional utility value.