• Korean Chemical Engineering Research
• /
• v.59 no.1
• /
• pp.127-137
• /
• 2021

Air emission charge for nitrogen oxide as a precursor of fine dust has been introduced and implemented within the country from 2020. Therefore, the development of economical combustion technology for NOx reduction has got more needed urgently. This study investigated the air-staging effect as a way to reduce the NOx during combustion of domestic unused forest biomass, recently possible to secure REC (Renewable Energy Certification) as a substitute for overseas wood pellets in a 0.1 MWth circulating fluidized bed combustion test-rig. Operating conditions were comparison with and without air-staging, the supply position of tertiary air (6.4 m, 8.1 m, 9.4 m in the combustor) and variation of air-staging ratio (Primary air:Secondary air:Tertiary air=91%:9%:0%, 82%:9%:9%, 73%:9%:18%). NO and CO concentrations in flue gas, profiles of temperature and pressure at the height of the combustion, unburned carbon in sampled fly ash and combustion efficiency on operating conditions were evaluated. As notable results, NO concentration with air-staging application under tertiary air supply at 9.4 m in the combustor reduced 100.7 ppm compared to 148.8 ppm without air-staging while, CO concentration increased from 52.2 ppm without air-staging to 99.8 ppm with air-staging. However, among air-staging runs, when tertiary air supply amount at 6.4 m in the combustor increased by air-staging ratio (Primary air:Secondary air:Tertiary air=73%:9%:18%), NO and CO concentrations decreased the lowest 90.8 ppm and 66.1 ppm, respectively. Furthermore, combustion efficiency at this condition was improved to 99.3%, higher than that (98.3%) of run without air-staging.

• Journal of Bio-Environment Control
• /
• v.31 no.1
• /
• pp.67-76
• /
• 2022

This study aimed to determine the photosynthesis and growth characteristics of Peucedanum japonicum T. grown under aquaponics in a plant factory (AP) by comparing those grown under hydroponic cultivation system (HP). The AP system raised 30 fishes at a density of 10.6 kg·m^-3 in a 367.5 L tank, and at HP, nutrient solution was controlled with EC 1.3 dS·m^-1 and pH 6.5. The pH level ranged from 4.0 to 7.1 for the AP system and 4.0 to 7.4 for the HP system. The pH level in the AP began to decrease with an increase in nitrate nitrogen (NO₃-N) and lasted bellower than pH 5.5 for 15-67 DAT. It was found that ammonium nitrogen (NH₄-N) continued to increase even under low pH conditions. EC was maintained at 1.3 to 1.5 dS·m^-1 in both systems. The concentration of major mineral elements in the fish tank was higher than that of the hydroponics, except for K and Mg. There was no significant difference in the photosynthesis characteristics, but the PIABS parameters were 30.4% lower in the AP compared to the HP at the 34DAT and 12.0% lower at the 74DAT. There was no significant difference in the growth characteristics, but the petiole length was 56% longer in the leaf grown under the AP system. While there was no significant difference in the fresh and dry weights of leaf and root, the leaf area ratio was 36.43% higher in the AP system. All the integrated results suggest that aquaponics is a highly-sustainable farming to safely produce food by recycling agricultural by-products, and to produce Peucedanum japonicum as much as hydroponics under a proper fish density and pH level.

• Journal of Industrial Convergence
• /
• v.21 no.3
• /
• pp.159-169
• /
• 2023

This study analyzed the factors affecting the opinions of life-sustaining treatment among the elderly in Korea. The study subjects were 10,097 people who responded to the survey on the condition of the elderly (2020), and using the SPSS 25.0 program, first, the demographic characteristics of the research subjects were identified through descriptive statistics and the average and normality of major variables were identified. Second, the chi-square was analyzed by conducting a cross-analysis of opinions on life-sustaining treatment according to the characteristics of the elderly. Third, a correlation analysis was performed to analyze the correlation between major variables. Fourth, the relative influence on the life-sustaining treatment of the elderly was identified through multiple regression analysis. The main research findings are as follows. First, 8,565 (84.8%) of the elderly were opposed to medical treatment (life-sustaining treatment) to save them even if they were unconscious or difficult to live. Second, as a result of cross-analysis on life-sustaining treatment for the elderly, the 𝑥² values of education level, health status, living together with children, and cost of living in old age were found to be significant. Third, the educational level of the elderly, living together with children, and the cost of living in old age were found to have statistically significant negative effects on life-sustaining treatment. Such research results indicate that the elderly with a high level of education oppose life-sustaining treatment compared to those with a low level of education. In addition, in the case of the elderly with traditional values who responded that one of their children should live with the elderly (parents), the ratio of people in favor of life-sustaining treatment was high, and in the case of the elderly with modern values who responded that they did not have to live together, the ratio of opposition to life-sustaining treatment was high. appeared to be high. In addition, in the case of the elderly with traditional values who responded that the burden of living expenses in old age should be shared between the state and society and their children, the proportion in favor of life-sustaining treatment was high. This high figure expressed the desire for well-dying. Based on these research results, the value system was re-examined as a factor influencing the elderly's opinion on life-sustaining treatment, and basic data for welfare policies for the elderly were provided.

• Therapeutic Science for Rehabilitation
• /
• v.13 no.1
• /
• pp.35-47
• /
• 2024

Objective : This study aimed to investigate the association between lifestyle factors and risk of frailty and depressive symptoms among older South Korean adults. Methods : This study included 10,072 individuals aged 65 or older from the 2017 National Survey of Older Koreans, a cohort of community-dwelling older South Koreans. The following lifestyle factors were assessed: physical activity, nutrition management (NM), and leisure/social activity participation (AP). Frailty was measured using the frail scale and depressive symptoms were measured using the Geriatric Depression Scale. Logistic regression analyses were performed to determine the odds ratios. Results : All lifestyle factors were associated with the risk of frailty and depressive symptoms in the study population. Regular exercise (≥3 times/wk, odds ratio [OR] = 0.59, 95% confidence interval [95% CI] = 0.52~0.91; OR = 0.66, 95% CI = 0.59~0.75), active NM (OR = 0.86, 95% CI = 0.80~0.91; OR = 0.81, 95% CI = 0.76~0.86), leisure AP (OR = 0.79, 95% CI = 0.74~0.84; OR = 0.71, 95% CI = 0.66~0.77) and social AP (OR = 0.92, 95% CI = 0.88~0.96; OR = 0.82, 95% CI = 0.78~0.87) were correlated with lower odds ratios of frailty and depressive symptoms. Conclusion : Adopting a healthier lifestyle characterized by regular exercise, balanced nutrition, and active engagement in various activities can effectively reduce the risk of frailty and depressive symptoms among the older population. Ultimately, this study emphasized the essential role of lifestyle choices in promoting the physical and mental well-being of older adults.

• Health Policy and Management
• /
• v.34 no.2
• /
• pp.211-221
• /
• 2024

Background: The public health crisis caused by coronavirus disease 2019 emphasizes the need to expand and strengthen public hospitals. However, the overall perception of public hospitals remains negative. This negative perception can hinder the roles and functions of public hospitals, so this study aims to analyze the factors affecting negative perceptions of public hospitals. Methods: We used data from a survey on the public healthcare of Chungcheongbuk-do residents conducted by the Chungcheongbuk-do Public Health Policy Institute, and 1,916 adults aged 19 or older who responded to the survey were included in the study. Logistic regression analysis was used to analyze the impact of experiences with public hospitals use and evaluations of public healthcare and public hospital policies on the negative perception of public hospitals. Results: The experience of not using public hospitals (adjusted odds ratio [aOR], 1.69; 95% confidence interval [CI], 1.04-2.74) and negative evaluations of public healthcare and public hospital policies were found to significantly impact negative perceptions of public hospitals. In public healthcare policies, negative evaluations of the provision of essential medical care (aOR, 4.14; 95% CI, 2.59-6.62), regional disparities (aOR, 1.59; 95% CI, 1.02-2.49), coverage (aOR, 1.99; 95% CI, 1.25-3.16), and quality of care (aOR, 2.39; 95% CI, 1.50-3.80) were significantly associated with negative perceptions of public hospitals. In public hospital policies, negative evaluations of facilities and equipment (aOR, 3.74, 95% CI, 2.36-5.94), medical specialties and services (aOR, 1.91; 95% CI, 1.21-3.01), and quality of medical service (aOR, 2.71; 95% CI, 1.72-4.25) were also significantly associated with negative perceptions of public hospitals. Conclusion: This study emphasizes the need to improve perceptions of public hospitals by considering the experience with public hospitals use and evaluation of public healthcare and public hospital policies.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.38 no.2
• /
• pp.109-118
• /
• 2010

This study aims to propose practical strategies for the new urban ideal of regeneration. A book review highlights the emergence of new trends of urbanization in knowledge-information industrial society beyond the new town Ideal of the industrial society. The meaning of ‘landscape’ in landscape urbanism represents not the visual and decorative pictures, but the dynamic process in the context of changes and evolutions. Also, knowledge-information industrial society and landscape have a meaning in the same context of flow and process with changes of velocity. Finally, these key words convey a meaning with the new urban trends of urbanization in knowledge-information industrial society in the context of value-oriented characteristics of dynamics and process. Urban regeneration is emerging as the new urban ideal in the knowledge-information industrial society, beyond the new town ideal of industrial society. It is in the same context as landscape urbanism with respect to green infrastructure buildings and designs for the transformation of urban surfaces covered with concrete and asphalt into the ecological surface, and of the ecological surfaces into the cultural surface that could be communicated with human beings. This research revealed the six strategies for urban regeneration as follows. The First, the strategies for the transformation of urban surfaces into ecological surfaces, the second, the strategies for the transformation of ecological surfaces into cultural surfaces, the third, the introduction of mixed and convergence land use, the forth, the transformation of former sites(e.g. military and factory) into urban parks, the fifth, the introduction of waterfront park zones that have the function of ecological and park-oriented mixed land use and, the sixth, the building and design of green infrastructure in the residential and commercial complex in CBD. These strategies call for the reforms of development laws and regulations to restrict building coverage ratio, building heights, and the introduction of park-oriented mixed zoning regulations. Another method for implementating the above listed strategies was the introduction of a strategic planning system instead of the traditional master plan system. This system uses a value planning approach and brand making by imagery. It is able to construct the meaning of an image and its creativeness directly.

• Therapeutic Science for Rehabilitation
• /
• v.9 no.1
• /
• pp.24-44
• /
• 2020

Objective : To develop an occupation-based bilateral upper extremity training protocol that can be effectively applied in a medical setting Methods : The research process using the delphi technique was carried out in 3 stages. The first stage was an open questionnaire development stage, The first draft is prepared through literature review and open questions were developed through preliminary research based on the draft. The second stage was the delphi survey. Based on the responses of the experts obtained through the open Delphi survey, the adequacy of the training protocol was shown on a Likert 5 point scale. The items were edited and deleted, reconstructed by analyzing the mean and standard deviation, stability, convergence degree, consensus, and content validity ratio through the questionnaire. The third step was the completion of the protocol. After discussions between researchers, the finalized protocol contents were reorganized to complete the occupation-based bilateral upper extremity training protocol for medical setting. Results : The final protocol consisted of 9 items across 3 areas in the occupation-based intervention selection domain and 81 items across 4 areas in the bilateral upper extremity training domain, intervention period, and evaluation. Conclusions : This study suggests an evidence-based method that collects the opinions of occupational therapists in order to use occupation-based activities as interventions in a situation that currently sees occupational therapy primarily performed in hospitals. It is also meaningful that the bilateral upper extremity training can be applied effectively in clinical situations by concretely presenting.

• Journal of Veterinary Clinics
• /
• v.29 no.3
• /
• pp.233-236
• /
• 2012

Cefquinome, a fourth generation cephalosporin, has been solely used for veterinary medicine and has a broad antibacterial spectrum against gram-negatives and gram-positives being very stable to ${\beta}$-lactamases. This study was conducted to evaluate the bioequivalence of two cefquinome 2.5% products in piglets. Plasma cefquinome concentrations were analyzed by liquid chromatography-mass spectrometry (LC/MS). Mean maximum concentration ($C_{max}$) of test product ($Cequus^{(R)}$) and reference product ($Cobactan^{(R)}$) were $4.34{\pm}0.58$ and $4.22{\pm}0.47{\mu}g/mL$, and mean area under the concentration time curve ($AUC_{0{\rightarrow}{\infty}}$) values were $10.43{\pm}1.96$ and $10.25{\pm}2.98{\mu}g{\cdot}h/mL$, respectively. The 90% confidence intervals for the ratio of $C_{max}$ (0.941-1.115), and $AUC_{0{\rightarrow}{\infty}}$ (0.927-1.172) values for the test and reference products were within the acceptable bioequivalence limit of 0.80-1.25. It is concluded that two commercial cefquinome injectable solutions are bioequivalent in their extent of drug absorption in piglets.

• Korean Chemical Engineering Research
• /
• v.56 no.1
• /
• pp.6-13
• /
• 2018

Utilizing the heat of cooling water discharge of coal-fired power plant, pipeline investment costs for businesses that supply heat to agricultural facilities near power plants increase in proportion to installation distance. On one hand, the distance from the power plant is a factor that brings difficulties to secure economic efficiency. On the other, if the installation distance is short, there is a problem of securing the heating demands, facility houses, which causes economical efficiency to suffer. In this study, the economic efficiency of 1km length of standard heat pipeline was evaluated. The sensitivity of the heat pipe to the new length variation was analyzed at the level of government subsidy, amount of heating demand and the incremental rate of pipeline with additional government subsidy. As a result of the analysis, it was estimated that NPV 131 million won and IRR 15.73%. The sensitivity analysis showed that NPV was negative when the length of heat pipe facility exceeded 2.6 km. If the government supports 50% of the initial investment, the efficiency is secured within the estimated length of 5.3 km, and if it supports 80%, the length increases within 11.4 km. If the heat demand is reduced to less than 62% at the new length of the standard heat pipe, it is expected economic efficiency is not obtained. If the ratio of government subsidies to initial investment increases, the elasticity of the new bloc will increase, and the fixed investment, which is the cost of capital investment for one unit of heating demand, will decrease. This would result in a reduction in the cost of production per unit, and it would be possible to supply heat at a cheaper price level to the facility farming. Government subsidies will result in the increased economic availability of hot plumbing facilities and additional efficiencies due to increased demand. The greater government subsidies to initial investment, the less farms cost due to the decrease in the price per unit. The results of the study are significant in terms of the economic evaluation of the effectiveness of the government subsidy for the thermal power plant heat utilization project. The implication can be applied to any related pilot to come.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.14 no.4
• /
• pp.113-132
• /
• 2019

The degree of females' participation in corporate activity has been recently increased over the world and females' participation in economic activity may be new dynamic fuel for the Korean economy that falls into the vicious cycle of low growth. Start-up, therefore, has increasingly taken attention as an opportunity for females whose careers were interrupted to re-enter the labor market. The need for studies that examine factors influencing the decision of start-up is also increased along with the increase of the ratio of females' start-up. This study aims to verify effects of the women's characteristics(women discrimination, women's role conflict) and the human networks of females whose careers were interrupted, with the intention for entrepreneurial intention, which are mediated by personal attitudes and subjective norm suggested by Ajzen's Theory of Reasoned Action, based on an empirical research. The findings show that the human networks of females have an effect on attitudes toward start-up activity and subjective norm and the woman discrimination influence the personal attitudes. In contrast, the women's role conflict have no effect on both personal attitude toward start-up activity and subjective norm. This can be supposed as an outcome resulted from the subjects' low level of conflict caused by their sex roles, on their age distribution. The relation between subjective norm and entrepreneurial Intention seemed to be moderated by their perceived strong entrepreneurial supporting policy. Their attitudes toward start-up activity were found to have a mediating effect on the relation between the women discrimination, human networks and entrepreneurial Intention, while the subjective norm only mediated the relation between human networks and entrepreneurial Intention. Based on such results, this study attempts to suggest theoretical suggestions and the direction of various entrepreneurial supporting policy for the increase and the growth of start-up of females whose careers were interrupted, in Korea.