• 한국환경생태학회지
• /
• 제16권3호
• /
• pp.223-232
• /
• 2002

자연생태계의 보전을 위한 지역구분을 위하여 백두대간(피재-도래기재) 구간을 조사한 식생조사 자료를 바탕으로 식생의 보전가치를 식생지수라는 것으로 수치화하는 방법을 제시해 보고자 한다. 식생지수는 생물다양성, 임분의 보전가치, 환경의 청정성, 임분의 역사성 입지의 생산성 등을 바탕으로 수치화하였다. 식생지수는 백두대간 관리범위 설정에 이용될 수 있을 것이라 사료된다. 식생지수 I의 경우 총 113개의 조사지 중에서 59개 지역 52.2%가 핵심지역에 속하고, 34개 지역 30.1%, 20개 지역 17.7%가 각각 완충지역과 전이지역에 속하는 것으로 나타났다. 식생지수II의 경우 49개 지역 43.4%가 핵심지역에 속하고, 38개 지역 33.6%, 26개 지역 23.0%가 각각 완충지역과 전이지역에 속하는 것으로 나타났다.

• Journal of the Korean Wood Science and Technology
• /
• 제47권6호
• /
• pp.667-673
• /
• 2019

The performance of a wooden deck made of refractory materials that have difficulties in achieving target penetrations as stipulated in the specification and quality standards for treated wood in Korea, was assessed via a case study in this research. A wooden deck built in Jinju in 2009 was selected for this study because of its fabrication method using pressure and treated refractory materials. The penetration and retention analysis did not satisfy the domestic standard for treated wood. Inspection of the deck in 2019 revealed that the deck had been attacked by decay fungi. Cap rails showed much deeper and wider checking on their surface compared with the top and base rails, resulting in a severe fungal attack. The decking boards exhibited severe fungal decay primarily in the end parts. However, the rails and balusters without checks and posts were virtually free of fungal attack irrespective of the preservative penetration measures. Copper content in the soil 5 cm away from the deck was less than 150 mg/kg, implying that copper movement in the soil was very limited. These results suggest that the inhibition of surface propagation and the protection of end surfaces are essential factors in increasing the longevity of treated wooden decks; further, the results also showed that the deck was within an acceptable range from the point of copper contamination.

• 디지털산업정보학회논문지
• /
• 제18권4호
• /
• pp.111-122
• /
• 2022

Many companies are now studying these generational conflict issues and seeking countermeasures. As seen in the recent performance-based pay issue, the MZ generation is boldly showing their intention unlike the previous generation. This study focuses on LX Hausys' education program to overcome the generation gap. As a representative field education program of LXHausys, it is a longevity education program that was developed and operated at the end of 14 years and has been in operation so far. By acknowledging and understanding the generation gap through this educational program, it was possible to see that they could sympathize and accept each other one step further, and that trust in each other was formed on the basis of it. The success factors of the generation empathy program were identified as the willingness to share perceptions between labor and management, participatory education programs, active participation of members, and overcoming generation empathy. Through such education, the organization should continuously raise the issue of generational empathy and allow members to recognize it as an object to overcome. To this end, efforts should be made to overcome generational differences.

• Corrosion Science and Technology
• /
• 제22권4호
• /
• pp.273-286
• /
• 2023

Rebar is embedded in concrete to create reinforced concrete (RC). Rebar carries most of the tensile stress and gives compressively loaded concrete fracture resistance. However, embedded steel corrosion is a significant cause of concern for RC composite structures worldwide. It is one of the biggest threats to concrete structures' longevity. Due to environmental factors, concrete decays and reinforced concrete buildings fail. The type and surface arrangement of the rebar, the cement used in the mortar, the dosing frequency of the concrete, its penetrability, gaps and cracks, humidity, and, most importantly, pollutants and aggressive species all affect rebar corrosion. Either carbonation or chlorides typically cause steel corrosion in concrete. Carbonation occurs when carbon dioxide in the atmosphere combines with calcium within the concrete. This indicates that the pH of the medium is falling, and the steel rebar is corroding. When chlorides pass through concrete to steel, corrosion rates skyrocket. Consideration must be given to concrete moisture. Owing to its excellent resistance, dry concrete has a low steel corrosion rate, whereas extremely wet concrete has a low rate owing to delayed O₂ transfer to steel surfaces. This paper examines rebar corrosion causes and mechanisms and describes corrosion evaluation and mitigation methods.

• Geomechanics and Engineering
• /
• 제37권1호
• /
• pp.21-29
• /
• 2024

The effective management of damage in tunnels is crucial for ensuring their safety, longevity, and operational efficiency. In this paper, we propose an educational management model tailored specifically for addressing damage in tunnels, utilizing numerical solution techniques. By leveraging advanced computational methods, we aim to develop a comprehensive understanding of the factors contributing to tunnel damage and to establish proactive measures for mitigation and repair. The proposed model integrates principles of tunnel engineering, structural mechanics, and numerical analysis to facilitate a systematic approach to damage assessment, diagnosis, and management. Through the application of numerical solution techniques, such as finite element analysis, we demonstrate the efficacy of the proposed model in simulating various damage scenarios and predicting their impact on tunnel performance. Additionally, the educational component of the model provides valuable insights and training opportunities for tunnel management personnel, empowering them to make informed decisions and implement effective strategies for ensuring the structural integrity and safety of tunnel infrastructure. Overall, the proposed educational management model represents a significant advancement in tunnel management practices, offering a proactive and knowledge-driven approach to addressing damage and enhancing the resilience of tunnel systems.

• Biomolecules & Therapeutics
• /
• 제23권1호
• /
• pp.77-83
• /
• 2015

The seed of Vigna angularis has long been cultivated as a food or a folk medicine in East Asia. Genistein (4',5,7-trihydroxyisoflavone), a dietary phytoestrogen present in this plant, has been known to possess various biological properties. In this study, we investigated the possible lifespan-extending effects of genistein using Caenorhabditis elegans model system. We found that the lifespan of nematode was significantly prolonged in the presence of genistein under normal culture condition. In addition, genistein elevated the survival rate of nematode against stressful environment including heat and oxidative conditions. Further studies demonstrated that genistein-mediated increased stress tolerance of nematode could be attributed to enhanced expressions of stress resistance proteins such as superoxide dismutase (SOD-3) and heat shock protein (HSP-16.2). Moreover, we failed to find genistein-induced significant change in aging-related factors including reproduction, food intake, and growth, indicating genistein exerts longevity activity independent of affecting these factors. Genistein treatment also led to an up-regulation of locomotory ability of aged nematode, suggesting genistein affects healthspan as well as lifespan of nematode. Our results represent that genistein has beneficial effects on the lifespan of C. elegans under both of normal and stress condition via elevating expressions of stress resistance proteins.

• 대한예방한의학회지
• /
• 제19권3호
• /
• pp.171-178
• /
• 2015

Objective : To assess the utilization patternsand satisfaction factors of Traditional Korean Medicine(TKM) in Korea. Method : The study design of this paper is from a nationally representative random e-mails and interview surveys. In this survey, we asked 2000 Korean adults between the ages of 20 and 69, whether they have used TKM in the past three years and if so, what were their experiences and how satisfied they were with the care they have received. Results : Sixty percent of respondents(n=1239) answered that they had used TKM in the past three years. The odds of using TKM were higher in female(OR 1.48; 95% CI 1.24-1.78) and academic backgrounds of university graduate or beyond (OR 1.27; 95% CI 1.01-1.60), and lower in unmarried person (OR 0.68; 95% CI 0.55-0.84) in the multivariable analysis. The most frequent purpose for seeking TKM and receiving treatment was to 'treat illness'.In addition, the use herbal medicine among types of TKM is statistically significant in sexual groupings.748(60.4%) among TKM users responded that they had a satisfying experience during TKM treatment. In multivariable logistic model, the odds of satisfaction from using TKM were higher in employed groups(OR 1.34; 95% CI 1.02-1.77), the reason for using of personalized medicine into TKM(OR 1.50; 95% CI 1.00-2.26). Conclusion : Korean traditional medicine doctors need to develop and provide the personalized medicine for the group of high utilization rate and satisfaction, and make strategies to disseminate TKM utilization for the group of lower utilization.

• 한국치위생학회지
• /
• 제20권1호
• /
• pp.95-106
• /
• 2020

Objectives: This study was conducted to investigate the effects of dental hygienists' job satisfaction on turnover intention and intention to stay. Methods: A survey was conducted targeting 273 dental hygienists in dental clinics. The study data were u analyzed using PASW Statistics 20.0 Results: The level of job satisfaction of dental hygienists was 3.30±0.50, and the highest ranked item in the survey was 'I am satisfied with my relationships with patients' 3.72±0.73. Job satisfaction according to general characteristics showed significant differences in age, marriage, education, career, current work experience, position, and schedule for future turnover. The turnover intention according to general characteristics showed significant difference in age and schedule for future turnover. The intention to stay according to general characteristics showed significant differences in age, marriage, education, career, current work experience, number of dentists, number of dental hygienists, and schedule for future turnover. The factors affecting turnover intention were schedule for future turnover, income, co-worker relation and professional time, while those affecting intention to stay were overall professional satisfaction, co-worker relation, schedule for future turnover, professional time, income, number of dental hygienists, patient relations and current work experience. Conclusions: Job satisfaction factors that had a common effect on turnover intention and intention to stay were schedule for future turnover, income, co-worker relation and professional time. To reduce turnover and encourage longevity, adequate pay and positive interpersonal relationships are necessary.

• Natural Product Sciences
• /
• 제21권2호
• /
• pp.128-133
• /
• 2015

Lindera obtusiloba has been widely used as a traditional medicine for the treatment of lots of diseases, including abdominal pain, bruise, and hepatocirrhosis. Here in this study, we elucidated the lifespan-extending effect of methanolic extract of Lindera obtusiloba (MLO) using Caenorhabditis elegans model system. We found that MLO has potent lifespan extension activities under normal culture condition. Then, we determined the protective effects of MLO on the stress conditions such as osmotic, thermal and oxidative stress. To reveal possible mechanism of MLO-mediated lifespan, we further investigated the effect of MLO on the antioxidant enzyme activities and intracellular ROS levels. Our results demonstrated that superoxide dismutase and catalase activities were significantly up-regulated by MLO treatment, resulted in reduced intracellular ROS levels. In this work, we also tested whether MLO-mediated longevity activity was associated with aging-related factors such as food intake and growth. Our data revealed that both of pharyngeal pumping rate and body length were significantly shifted by MLO treatment, indicating these factors were involved in MLO's lifespan-extension effects. Although MLO induces reduction in food intake, the body movement of MLO-fed aged worms was not decreased, compared to untreated control worms, indicating MLO might extend lifespan without affecting healthspan.

• Journal of Nutrition and Health
• /
• 제39권3호
• /
• pp.286-298
• /
• 2006

The study aimed to identify major factors related to global self-rated health of the community-dwelling elderly people in rural areas. Interviews were conducted with 433 persons over 65 years of age. The socio-economic characteristics, chronic disease status, measures of functional and mental health, life satisfaction, health-related behaviors including smoking, drinking, exercise, social activity, dietary habit, and food intakes were analyzed to determine their influence on self-rated health index. Data on food intake were obtained through the 24-hour recall method. The self-rated health of rural elderly was poor or very poor as reported by 42.6% and 52.4% of the men and women, respectively. Poor self-rated health was found to be related to elderly aged $65{\sim}74$, female, absence of work, more chronic diseases, dependence on Instrumental Activity Daily Living (IADL), higher mental unhealthy days, lower current life satisfaction, less social activity, lower dietary habit scores, lower intake of total food, fruit, eggs, fishes & shell fishes, vitamin C (%RDA), and Nutrient Adequacy Ratio (NAR). The results of the multiple regression analysis showed that poor self-rated health index is significantly associated with more chronic diseases, mental unhealthy days, gastrointestinal disease, musculoskeletal disease, less social activity, and lower intake of fruits. The results also suggested that improving the nutritional status and functional ability, and reducing the burden of chronic diseases are beneficial to the self-rated health index of the elderly.