• Journal of the Korean Geophysical Society
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• v.3 no.4
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• pp.269-280
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• 2000

Rail vibration in city zone is becoming a serious environmental problem. In order to make a reduction plan for rail vibration, the research was conducted in which many experiments to measure actual rail vibration along the railroad through the central Deajeon area. A digital vibration level meter was used to measure rail vibration. Vibration levels of Z-axis were measured at every second for the duration of the train passing. The measuring station was placed at every 5m for the distance of 55m. A total of 353 different sets of vibration level were obtained. The signals were processed to get $L_{10}$ value and analyzed in terms of distance, train velocity, and number of trains. As a result, it has been found that rail vibration exceed the allowable vibraton limit of 60 dB, at the point of 25 m far from the railroad center, which is regulated by the las of vibration and noise. Train velocity was found to affect a little for vibration level within the zone. It was also found that a trench installed along a railroad could reduce vibration level up to approximately 10 percent. A model test was conducted to investigate the influence of the location and size of trench, on the transfer of vibration. A heavy steel ball was used to generate vibrations. On the basis obtained from this study, it could be concluded that the application of distance-attenuation and the installment of a trench along railroad could be applied as a reduction plan for rail vibration. Because limitions might exist to depend on the effect of distance attenuation, trenchs excavated along a railroad might be suggested as the most efficient solution to reduce railroad vibration.

• Journal of Venture Innovation
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• v.6 no.4
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• pp.63-81
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• 2023

The purpose of this study was to utilize the Photovoice qualitative research method targeting university students. Through this method, we aimed to understand the perceptions of environmental issues, environmental barriers, and eco-friendly behaviors among university students. By employing the Photovoice methodology, we sought to share the perspectives of university students on eco-friendly behaviors, explore the motivations and manifestations of these behaviors, and reflect on their significance. The ultimate goal was to provide practical suggestions for fostering eco-friendly behaviors through an in-depth examination of the visual narratives and reflections of university students. Under the overarching theme of the environment, participants were given the opportunity to individually select and explore three specific sub-themes: 'My Concept of the Environment,' 'Environmental Barriers in My Life,' and 'My Eco-friendly Behaviors.' Participants engaged in the process of capturing photographs from their daily lives related to each theme, expressing their thoughts and perspectives through the selected images. Subsequently, they shared and discussed their insights, actively listening to the opinions of others in the group. The results of this study revealed several key findings. Firstly, participants assigned meaning to the photographs they selected by directly capturing aspects related to the environment, such as 'waste,' 'discomfort,' 'fine dust=environmental pollution,' and 'indifference.' Secondly, participants attributed meaning to the selected photographs related to environmental barriers, associating them with concepts like 'invisibility,' 'apathy,' 'social stigma,' 'inefficiency,' and 'compulsion.' Lastly, participants ascribed significance to photographs selected in the context of eco-friendly behaviors, with themes like 'recycling,' 'energy conservation,' 'reuse,' and 'reducing the use of disposable items.' Based on these research findings, the confirmation of the V-A-B (Values-Attitudes-Behavior) model was established. It was observed that consumers structure a hierarchical relationship between their personal values, attitudes, and behaviors. The study also identified clear impediments in consumers' daily lives hindering the practice of eco-friendly behaviors. In light of this, the research highlighted the need for strategies to address the discomfort or inconvenience associated with implementing environmentally friendly consumer behaviors. The implications of the study suggest that interventions or solutions are necessary to alleviate barriers and promote a more seamless integration of eco-friendly practices into consumers' daily routines.

• Korean Journal of Food Science and Technology
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• v.46 no.1
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• pp.108-114
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• 2014

To analyze the hazards associated with cucumber and hot pepper cultivation areas, a total of 72 samples were obtained and tested to detect the presence of biological (sanitary indicative, pathogenic bacteria and fungi) and chemical hazards (heavy metals and pesticide residues). The levels of sanitary indicative bacteria (aerobic plate counts and coliforms) and fungi were ND-7.2 and ND-4.8 log CFU/(g, mL, hand, or $100cm^2$) in cucumber cultivation areas, and ND-6.8 and 0.4-5.3 log CFU/(g, mL, hand, or $100cm^2$) in hot pepper cultivation areas. More specifically, the soil of hot pepper cultivation areas was contaminated with coliforms at a maximum level of 5.6 log CFU/g. Staphylococcus aureus was detected only in glove samples at a level of 1.4 log CFU/$100cm^2$ and Bacillus cereus was detected in the majority of samples at a level of ND-4.8 log CFU/(g, mL, hand, or $100cm^2$). Listeria monocytogenes, Escherichia coli O157:H7, and Salmonella spp. were not detected. Heavy metal (Zn, Cu, Ni, Pb, and Hg) chemical hazards were detected at levels lower than the regulation limit. Residual insecticides were not detected in cucumbers; however, hexaconazole was detected at a level of 0.016 mg/kg (maximum residue limit: 0.3 mg/kg) in hot peppers.

• Journal of the Korean Society of Food Science and Nutrition
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• v.45 no.7
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• pp.1071-1076
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• 2016

The feasibility of incorporating aronia powder (AP) as a value-added food ingredient into convenient food products was investigated using cookie as a model system. AP was incorporated into cookies at amounts of 0, 1, 2, 3, and 4% (w/w) based on total weight of wheat flour. The pH level of cookie dough decreased significantly with increasing levels of AP (P<0.05), whereas moisture content and density were not directly affected by levels of AP incorporation. The spread ratio increased significantly upon addition of AP; however, it was not significantly affected by level of AP incorporation. The loss rate of cookies decreased significantly with increasing levels of AP (P<0.05). In terms of color, lightness and yellowness decreased while redness increased significantly (P<0.05) with increasing levels of AP. Use of AP significantly decreased hardness of cookies (P<0.05), but no significant differences were found between control and 1% sample, 1% and 2% sample, 2% and 3% sample, and 3% and 4% sample (P>0.05). 2,2-Diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) radical scavenging activities were significantly elevated by AP addition, and they increased significantly as AP concentration increased in the formulation (P<0.05). Correlation analysis indicated that acceptances of color and chewiness were negatively correlated well with the level of AP incorporation, density and moisture content of cookie dough, and cookie redness, whereas they were positively correlated with pH of cookie dough, loss rate, and hardness (P<0.01 or P<0.05). Finally, consumer acceptance test indicated that the highest levels of AP incorporation (4%) had an adverse effect on general consumer preferences. In contrast, cookies with moderate levels of AP (2%) are recommended based on overall scores to take advantage of the antioxidant properties of AP without sacrificing consumer acceptability.

• Tuberculosis and Respiratory Diseases
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• v.45 no.4
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• pp.697-704
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• 1998

Background: Asthma is a chronic inflammatory disease of the airways characterized by a marked infiltration of eosinophils in the bronchial mucosa. Asthmatic bronchial mucosa produces many factors described as being chemotactic for inflammatory cells. IL-5, RANTES, and MCP-1 alpha are the chemotactic factors for eosinophils, but their roles are controversial. Recently eotaxin that is a potent eosinophil chemoattractant cytokine was detected in a guinea-pig model of allergic airway inflammation, and human eotaxin was cloned. Eotaxin is a specific chemoattractant for eosinophils, but its role in asthma is not confirmed. We examined the in vivo expression of eotaxin in bronchi of asthmatic patients. Methods : 11 asthmatics and 2 normal controls were enrolled. All subjects were underwent bronchoscopy with bronchial biopsies in 2nd or 3rd carina. RNA extraction from biopsy samples was done by acid-guanidium method. Semi-quantitaive RT-PCR was done for evaluation of eotaxin mRNA expression The extent of eosinophil infiltration was evaluated by counting the eosinophils in submucosa in HPF of microscope. Results : Eotaxin mRNA expressed in symptomatic, uncontrolled asthma. Steroid inhibited expression of eotaxin mRNA in asthma. Expression of eotaxin mRNA correlated with eosinophil infiltration in bronchial tissues. Conclusion: Expression of eotaxin mRNA increases in uncontrolled asthma and eotaxin is involved in the recruitment of eosinophils.

• Korean Journal of Ecology and Environment
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• v.42 no.2
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• pp.260-269
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• 2009

Hwabuk Dam has been under construction to reduce flood damage in Nakdong River watershed and to supply stable water for middle area of Gyeongbuk Province. Therefore, fish investigation in up and downstream of the dam was conducted from 2004 to 2008 in order to determine any negative effect on fish community due to dam construction and to use as fundamental data for conserving species diversity and maintaining stream health. According to data analysis on water quality, temperature, dissolved oxygen, pH, suspended solids, and total E-coli had seasonal variation, but they did not significantly differ in sites. However, biological and chemical oxygen demand, chlorophyll-a, nitrogen, and phosphorus representing organic matter and nutrient concentration were higher in upper site and decreased to lower site so that they differed by site. Concentration of arsenic among the heavy metals was less than 0.05 mg $L^{-1}$, which is regulated for protection of human health in water quality standard, except for 0.092 mg $L^{-1}$ in June 2005. During the study period, the total number of fish caught from the 6 sites was 10,263 representing 7 families 19 species. Among them, dominant and subdominant species were Korean chub (Zacco koreanus, 62.5%) and Chinese minnow (Rhynchocypris oxycephalus, 10.6%) which inhabit mostly in mid and upper streams, Korea. Among the 19 species, Korean endemic species were 9 species (47.4%) including Korean slender gudgeon (Squalidus gracilis majimae), Korean dark sleeper (Odontobutis platycephala), and Korean shiner (Coreoleuciscus splendidus). There was several individuals of the $1^{st}$-class endangered species, Naktong nose loach (Koreocobitis nahtongensis), caught in 2005${\sim}$2007, and no introduced species of fish was found in entire sampling period. According to result of community analysis, dominance index decreased toward lower site, but diversity and richness indices increased toward lower site. The equation of length-weight relationship on the dominant species was TW=0.000003$(TL)^{3.2603}$. The parameter b in the equation was greater than 3.0 indicating good nutritional condition in the populations. Compared to populations of Korean chub in other streams, the population in Hwabuk Dam watershed had higher mean of condition factor by size indicating better growth rate. With fish fauna and multi-metric health assessment model in each sampling attempt, index of biotic integrity (IBI) was evaluated and it resulted mostly in good (26${\sim}$35) and excellent (36${\sim}$40) condition in all sites, and the mean of IBI was the highest in site 5. The results indicate that it is very important to study not only environmental impact assessment with fish composition but also stream health assessment in order to conserve healthy aquatic ecosystem.

• Journal of Environmental Policy
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• v.9 no.2
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• pp.157-184
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• 2010

Global climate change is destroying the water circulation balance by changing rates of precipitation, recharge and discharge, and evapotranspiration. The Intergovernmental Panel on Climate Change (IPCC 2007) makes "changes in rainfall pattern due to climate system changes and consequent shortage of available water resource" a high priority as the weakest part among the effects of human environment caused by future climate changes. Groundwater, which occupies a considerable portion of the world's water resources, is related to climate change via surface water such as rivers, lakes, and marshes, and "direct" interactions, being indirectly affected through recharge. Therefore, in order to quantify the effects of climate change on groundwater resources, it is necessary to not only predict the main variables of climate change but to also accurately predict the underground rainfall recharge quantity. In this paper, the authors selected a relevant climate change scenario, In this context, the authors selected A1B from the Special Report on Emission Scenario (SRES) which is distributed at Korea Meteorological Administration. By using data on temperature, rainfall, soil, and land use, the groundwater recharge rate for the research area was estimated by period and embodied as geographic information system (GIS). In order to calculate the groundwater recharge quantity, Visual HELP3 was used as main model for groundwater recharge, and the physical properties of weather, temperature, and soil layers were used as main input data. General changes to water circulation due to climate change have already been predicted. In order to systematically solve problems associated with how the groundwater resource circulation system should be reflected in future policies pertaining to groundwater resources, it may be urgent to recalculate the groundwater recharge quantity and consequent quantity for using via prediction of climate change in Korea in the future and then reflection of the results. The space-time calculation of changes to the groundwater recharge quantity in the study area may serve as a foundation to present additional measures for the improved management of domestic groundwater resources.

• Journal of Animal Science and Technology
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• v.44 no.5
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• pp.499-506
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• 2002

This study was conducted to estimate the heritabilities and genetic and phenotypic correlations among average daily gain, age at 90kg and backfat thickness in Yorkshire pigs. The data were obtained from 2,111 heads of Yorkshire tested at National Livestock Research Institute from May, 1994 to April, 2000. Genetic parameters were estimated with a multiple trait animal model by using DF-REML (Deri- vative-Free REstricted Maximum Likelihood). The results obtained are summarized as follows ; The means of traits studied were 0.871${\pm}$0.124 kg for average daily gain, 145.397${\pm}$11.718 days for age at 90kg and 1.476${\pm}$0.241 cm for backfat thickness. The estimated heritabilities were 0.55 for average daily gain, 0.56 for age at 90kg and 0.55 for backfat thickness. The genetic correlation of average daily gain with age at 90kg and backfat thickness were －0.82, 0.10, respectively. The genetic correlation of age at 90kg with backfat thickness was －0.25. The phenotypic correlations of average daily gain(ADG) with age at 90kg and backfat thickness and age at 90kg with backfat thickness were －0.77, 0.02 and －0.05 respectively. Though phenotypic correlation of ADG and age at 90kg was low, breeding project should be carefully considered by high genetic correlation. High heritabilities on all economic traits were obtained. Therefore, it is considered that suitable selection and management is needed successful improvement.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.15 no.1
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• pp.143-150
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• 2020

This research is intended to identify how office worker's recognition of strength affects the intention of starting a business when it is used as a medium for utilizing strength. The survey period was conducted for two months from January 17, 2019 to March 8, 2019. In order to achieve the object of this study, a significant number of employees have been collected nationwide, and 287 office workers were analyzed after collecting 300 questionaires, excluding 13 office workers who were not sincere. The significant data were analyzed by utilizing the structural equation and technical statistics and by verifying the conformity of structural model and measurement model and by investigating the relationship between variables. The results of this study are summarized as follows: First, employee's perception of strength has been found to have a significant effect on the utilizing of strength. Second, the use of workers' strengths has been found to have a significant effect on the intention of starting a business. Third, it has been confirmed that in the relationship between the employee's perception of strength and intention to start a business, the recognition of strength has a significant effect on the intention of starting a business only through the use of strength. Most office workers are nervous about the future and make various plans. The time to live after retirement is getting longer and jobs and working hours are shrinking at an alarming rate. According to the analysis on the status of small business owners in the mid-term of 2017 data, the average monthly operating profit of small business owners across the country is decreasing over the years, and most start-ups are subsistence-type start-ups, and they decide to start their own businesses because they have no other choice than start-ups. As the number of small business owners suffering from financial difficulties has increased since the financial crisis and insecurity of job is pushing those with financial difficulties after retirement to the battleground of the start-up market, the result of this research suggest that the workers need to recognize their own strength and enhance the importance of utilizing the strength.

• Korean journal of communication and information
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• v.44
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• pp.76-107
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• 2008

The present study has explored the effects of media use on the evaluation of the presidential candidate's morality. We hypothesized that the perception of the candidates' morality during the 2007 Korean President Election would be influenced by the amount of the different types of media use. Using a set of panel data, a total of 1,199 citizens (584 females (48.7%), 615 males (51.3%), Mage=42.77, SDage=13.34) were assessed four times from August to December in 2007. The results indicated that (a) the level of TV use for political information, the level of newspaper use for political information, and the level of Internet use for political information increased during the five months; (b) the initial level of political involvement contributed differently to the initial levels of media use; (c) the initial level of political involvement negative influenced the initial level of TV use for political information; (d) the growth of political involvement positively influenced the growth of TV use for political information; (e) the intial level of TV use for political information increased both the initial levels of the perception of candidates' morality and the change of the perception of candidates' morality; (f) the change of TV use for political information negatively affected the perception of candidates' morality; and (g) the initial level of Internet use for political information negatively affected the initial level of the perception of candidates' morality, and the change of Internet use for political information negatively affected the perception of candidates' morality.