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Analysis on dynamic numerical model of subsea railway tunnel considering various ground and seismic conditions (다양한 지반 및 지진하중 조건을 고려한 해저철도 터널의 동적 수치모델 분석)

  • Changwon Kwak;Jeongjun Park;Mintaek Yoo
    • Journal of Korean Tunnelling and Underground Space Association
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    • v.25 no.6
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    • pp.583-603
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    • 2023
  • Recently, the advancement of mechanical tunnel boring machine (TBM) technology and the characteristics of subsea railway tunnels subjected to hydrostatic pressure have led to the widespread application of shield TBM methods in the design and construction of subsea railway tunnels. Subsea railway tunnels are exposed in a constant pore water pressure and are influenced by the amplification of seismic waves during earthquake. In particular, seismic loads acting on subsea railway tunnels under various ground conditions such as soft ground, soft soil-rock composite ground, and fractured zones can cause significant changes in tunnel displacement and stress, thereby affecting tunnel safety. Additionally, the dynamic response of the ground and tunnel varies based on seismic load parameters such as frequency characteristics, seismic waveform, and peak acceleration, adding complexity to the behavior of the ground-tunnel structure system. In this study, a finite difference method is employed to model the entire ground-tunnel structure system, considering hydrostatic pressure, for the investigation of dynamic behavior of subsea railway tunnel during earthquake. Since the key factors influencing the dynamic behavior during seismic events are ground conditions and seismic waves, six analysis cases are established based on virtual ground conditions: Case-1 with weathered soil, Case-2 with hard rock, Case-3 with a composite ground of soil and hard rock in the tunnel longitudinal direction, Case-4 with the tunnel passing through a narrow fault zone, Case-5 with a composite ground of soft soil and hard rock in the tunnel longitudinal direction, and Case-6 with the tunnel passing through a wide fractured zone. As a result, horizontal displacements due to earthquakes tend to increase with an increase in ground stiffness, however, the displacements tend to be restrained due to the confining effects of the ground and the rigid shield segments. On the contrary, peak compressive stress of segment significantly increases with weaker ground stiffness and the effects of displacement restrain contribute the increase of peak compressive stress of segment.

Analysis of risk evaluation procedures and consideration of risk assessment issues of living modified organisms for agricultural use in Korea (농업용(사료용) 유전자변형생물체의 위해성심사 제도 분석 및 환경위해성평가 관련 쟁점에 대한 고찰)

  • Myung-Ho Lim;Sang Dae Yun;Eun Young Kim;Sung Aeong Oh;Soon-Ki Park
    • Journal of Plant Biotechnology
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    • v.50
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    • pp.275-289
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    • 2023
  • Since the implementation of the Living Modified Organisms (LMOs) Act in 2008, approximately 10 million tons of genetically modified corn, soybean, potato, canola, and other crops have been imported into South Korea. The import approval procedures have been completed for approximately 191 cases that include seven crops. Of these, approximately 90 cases, excluding crossbreeds of approved LMOs, were reviewed via consultation risk evaluation in four areas: human health, crop culture, natural ecology, and marine fishery environment. LMO developers in South Korea, who are major stakeholders in the import of LMO crops produced overseas, have raised concerns regarding procedural inefficiency in consultation reviews and the need of excessive reviews that are unsuitable for food-feed processing purposes. These procedures reflect the perspective of consultation agencies that deviate from the nature of risk assessment and demand specific supplementary data that do not reflect familiarity and substantial equilibrium. Based on frequent instances of unintentional environmental release of LMO crops imported into Korea, the ministries responsible for consultation insist on a review that considers the climate and natural environment of Korea. In addition, the ministries mandate that their reviews reflect the expertise of competent ministries and are based on risk assessment principles and methods in accordance with international guidelines. In this regard, considering that traits introduced into LMO crops involving familiar agricultural crops have been considered safe for more than two decades, we have suggested reasonable alternatives to several risk assessment items for agricultural LMOs. These alternatives can mitigate conflicts of interest among key stakeholders within the scope of the current LMO regulations.

The Influence of K-Content Experience on National Image, Tourism Attitude and Visit to Intention: Targeting Chinese (K-콘텐츠 경험이 국가이미지와 관광태도 및 방문의도에 미치는 영향 : 중국인을 대상으로)

  • Park, Heejung
    • Journal of Service Research and Studies
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    • v.14 no.1
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    • pp.91-107
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    • 2024
  • This study attempted to empirically verify the possibility of K-content for Chinese people who have recently slowed down due to restriction of movement and political and diplomatic conflicts, although it is a very meaningful market for Korea's content industry and tourism industry. As a result of the study, each item of K-content experience, national image, tourism attitude, and visit intention was derived as one factor, and only the national image factor was derived as two factors: 'functional image' and 'cultural image'. As a result of examining the influence relationship between them established based on previous studies focusing on the derived factors, all five research hypotheses were adopted. K-content experience was found to have a significant influence on both factors of the national image. It was found that it had a greater influence on cultural image factors than functional image factors, cultural image factors were found to have a greater influence on tourism attitudes, K-content experiences had a significant effect on tourism attitudes, and tourism attitudes had a significant effect on visit intentions. Based on the results of this study, it was once again confirmed that the national image even comtually bees an important factor for linking to practical tourism behavior, and in this respect, "culture" is an important key factor that can lead to practical tourism and visits. Previous national images indicate that if the functional aspect of the country was more emphasized, it is now necessary to focus more on the importance of culture than on the functional aspect. As the K-content experience has a significant effect on tourism attitude, it can have a positive effect on the formation of a positive tourism attitude that can lead to actual tourism behavior, so various efforts will be needed to form an active tourism attitude using K-content in the future. As the content and target scope of K-content are expanded and diversified, specific strategies for each sub-market using cultural contents in various fields should be established and implemented.

Research on Immune Responses Induced by Salmonella Typhimurium Infectionin CRIP1-Deficient Condition (CRIP1결손조건 하에서 Salmonella Typhimurium 감염에 의해 유도되는 면역반응에 관한 연구)

  • Dongju Seo;Se-Hui Lee;Sun Park;Hyeyun Kim;Jin-Young Yang
    • Journal of Life Science
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    • v.34 no.1
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    • pp.48-58
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    • 2024
  • Salmonella is a common food-borne intracellular bacterial pathogen that has triggered significant public health concerns. Salmonella hosts' genetic factors play a pivotal role in determining their susceptibility to the pathogen. Cysteine-rich intestinal protein 1 (CRIP1), a member of LIM/double zinc finger protein family, is widely expressed in humans, such as in the lungs, spleen, and especially the gut. Recently, CRIP1 has been reported as a key marker of several immune disorders; however, the effect of CRIP1 on bacterial infection remains unknown. We aimed to elucidate the relationship between Salmonella infection and CRIP1 gene deficiency, as Salmonella spp. is known to invade the Peyer's patches of the small intestine, where CRIP1 is highly expressed. We found that CRIP1-deficient conditions could not alter the characteristics of bone marrow-derived myeloid cells in terms of phagocytosis on macrophages and the activation of costimulatory molecules on dendritic cells using ex vivo differentiation. Moreover, flow cytometry data showed comparable levels of MHCII+CD11b+CD11c+ dendritic cells and MHCII+F4/80+CD11b+ macrophages between WT and CRIP1 knockout (KO) mice. Interestingly, the basal population of monocytes in the spleen and neutrophils in MLNs is more abundant in a steady state of CRIP1 KO mice than WT mice. Here, we demonstrated that the CRIP1 genetic factor plays dispensable roles in host susceptibility to Salmonella Typhimurium infections and the activation of myeloid cells. In addition, differential immune cell populations without antigen exposure in CRIP1 KO mice suggest that the regulation of CRIP1 expression may be a novel immunotherapeutic approach to various infectious diseases.

Korean Clinical Imaging Guidelines for the Appropriate Use of Chest MRI (한국형 흉부 MRI 영상 진단 정당성 권고안)

  • Jiyoung Song;Bo Da Nam;Soon Ho Yoon;Jin Young Yoo;Yeon Joo Jeong;Chang Dong Yeo;Seong Yong Lim;Sung Yong Lee;Hyun Koo Kim;Byoung Hyuck Kim;Kwang Nam Jin;Hwan Seok Yong
    • Journal of the Korean Society of Radiology
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    • v.82 no.3
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    • pp.562-574
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    • 2021
  • MRI has the advantages of having excellent soft-tissue contrast and providing functional information without any harmful ionizing radiation. Although previous technical limitations restricted the use of chest MRI, recent technological advances and expansion of insurance coverage are increasing the demand for chest MRI. Recognizing the need for guidelines on appropriate use of chest MRI in Korean clinical settings, the Korean Society of Radiology has composed a development committee, working committee, and advisory committee to develop Korean chest MRI justification guidelines. Five key questions were selected and recommendations have been made with the evidence-based clinical imaging guideline adaptation methodology. Recommendations are as follows. Chest MRI can be considered in the following circumstances: for patients with incidentally found anterior mediastinal masses to exclude non-neoplastic conditions, for pneumoconiosis patients with lung masses to differentiate progressive massive fibrosis from lung cancer, and when invasion of the chest wall, vertebrae, diaphragm, or major vessels by malignant pleural mesothelioma or non-small cell lung cancer is suspected. Chest MRI without contrast enhancement or with minimal dose low-risk contrast media can be considered for pregnant women with suspected pulmonary embolism. Lastly, chest MRI is recommended for patients with pancoast tumors planned for radical surgery.

A Comparative Study between Donghak's In-nae-cheon and the Three Essential Attitudes in Daesoon Thought (동학 인내천과 대순사상 삼요체의 비교연구)

  • Kim Yong-hwan
    • Journal of the Daesoon Academy of Sciences
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    • v.48
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    • pp.269-303
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    • 2024
  • Donghak's teaching, In-nae-cheon, means "humans are divine." It is said, "When humans were formed, God's blessing was required for their formation." Donghak's Sincerity, Respectfulness, and Faithfulness is based on believing in God, respecting God, and practicing His teachings with utmost sincerity. These are key to implementing In-nae-cheon. On the other hand, the Three Essential Attitudes in Daesoon Thought, also Sincerity, Respectfulness, and Faithfulness, appear in a religious sense. These can be distinguished from Sincerity, Respectfulness, and Faithfulness in the Donghak moral sense. Sincerity, Respectfulness, and Faithfulness in the context of the Three Essential Attitudes in Daesoon Thought goes beyond moral awareness, and calls for belief in God as the Absolute. Accordingly, Sincerity, Respectfulness, and Faithfulness in this context, that of Daesoon Thought, aims at the realization of an Earthly Paradise wherein God's will can be achieved. Humans participating in the construction of Earthly Paradise value the practice of Sincerity, Respectfulness, and Faithfulness. In Daesoon Thought, it is said that when one exerts sincerity, respect, and faith in God (Sangje), all the blessings and fortune of the Later World, even those of longevity, will be endowed through transformation via effortless action (無爲而化). Accordingly, Sincerity, Respectfulness, and Faithfulness in the context of the Three Essential Attitudes in Daesoon Thought is based on God's descent into the world and His Reordering Works of Heaven and Earth (天地公事). This is a religious faith that worships Sangje and is based on the doctrinal dimension of 'guarding against self-deception (毋自欺)' and the philosophical dimension of Sincerity, Respectfulness, and Faithfulness in the context of the Three Essential Attitudes in Daesoon Thought. Donghak's In-nae-cheon and the Three Essential Attitudes in Daesoon Thought can be compared and analyzed. Therefore, in order to clearly compare and analyze the moral significance of Donghak history and the religious meaning of Daesoon Thought, Roderick Ninian Smart's method of religious phenomenology can be actively used. In this way, the ethical and legal dimensions of Donghak's In-nae-cheon and the doctrinal and philosophical dimensions of the Three Essential Attitudes in Daesoon Thought can be compared and analyzed. From this style of research, it can be concluded that the realization of commonly shared spirituality can be an opportunity for greater human dignity.

A Study on Factors Influencing the Management Performance of Small Business Owners : The Moderating Effect of Social Capital (소상공인의 경영성과에 미치는 영향 요인 연구 : 사회적자본의 조절효과)

  • Kim, Yong-keum;Heo, Chul-moo
    • Journal of Venture Innovation
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    • v.7 no.1
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    • pp.131-149
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    • 2024
  • This study was important considering the prevalence of small business owners in the Korean economy and the challenges they faced amidst an economic downturn. The business performance of these owners was crucial for their survival. Thus, an empirical analysis was conducted to identify factors influencing their management performance. The analysis included personal characteristics of small business owners such as innovativeness, management capability, need for achievement, and technical capability as independent variables, along with product differentiation factors. Additionally, the moderating effect of social capital on these variables and their impact on management performance was tested. To achieve this, a survey targeting small business owners across Korea was conducted, and data from 250 respondents were utilized. Hierarchical regression analysis using SPSS 24.0 was employed for the empirical analysis. The results indicated that management capability, need for achievement, and product differentiation significantly positively impacted business performance. However, the impact of innovativeness and technical capability was not tested. The influence of the variables on business performance ranked as follows: product differentiation, management capability, and need for achievement. The moderating effect of social capital was significant in the relationship between management capability, need for achievement, and management performance, enhancing these relationships. However, the moderating effect of social capital on the relationship between innovativeness, technical capability, product differentiation, and management performance was not tested. These findings underscored the importance of management capability, need for achievement, and product differentiation as key factors affecting the management performance of Korean small businesses. This study was significant as it provided insights into improving the management performance of small business owners in challenging economic conditions by highlighting how the influence of these factors varied depending on the social capital possessed by the owners.

Analysis of Changes in Pine Forests According to Natural Forest Dynamics Using Time-series NFI Data (시계열 국가산림자원조사 자료 기반 자연적 임분동태 변화에 따른 소나무림의 감소 특성 평가)

  • Eun-Sook Kim;Jong Bin Jung;Sinyoung Park
    • Journal of Korean Society of Forest Science
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    • v.113 no.1
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    • pp.40-50
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    • 2024
  • Pine forests are continuously declining due to competition with broadleaf trees, such as oaks, as a consequence of changes in the natural dynamics of forest ecosystem. This natural decline creates a risk of losing the various benefits pine trees have provided to people in the past. Therefore, it is necessary to prepare future forest management directions by considering the state of pine tree decline in each region. The goal of this study is to understand the characteristics of pine forest changes according to forest dynamics and to predict future regional changes. For this purpose, we evaluated the trend of change in pine forests and extracted various variables(topography, forest stand type, disturbance, and climate) that affect the change, using time-series National Forest Inventory (NFI) data. Also, using selected key variables, a model was developed to predict future changes in pine forests. As a results, it showed that the importance of pine trees in forests across the country has decreased overall over the past 10 years. Also, 75% of the sample points representing pine trees remained unchanged, while the remaining 25% had changed to mixed forests. It was found that these changes mainly occurred in areas with good moisture conditions or disturbance factors inside and outside the forest. In the next 10 years, approximately 14.2% of current pine forests was predicted to convert to mixed forests due to changes in natural forest dynamics. Regionally, the rate of pine forest change was highest in Jeju(42.8%) and Gyeonggi(26.9%) and lowest in Gyeongbuk(8.8%) and Gangwon(13.8%). It was predicted that pine forests would be at a high risk of decline in western areas of the Korean Peninsula, including Gyeonggi, Chungcheong, and Jeonnam. This results can be used to make a management plan for pine forests throughout the country.

<Field Action Report> Local Governance for COVID-19 Response of Daegu Metropolitan City (<사례보고> 코로나바이러스감염증-19 유행과 로컬 거버넌스 - 2020년 대구광역시 유행에 대한 대응을 중심으로 -)

  • Kyeong-Soo Lee;Jung Jeung Lee;Keon-Yeop Kim;Jong-Yeon Kim;Tae-Yoon Hwang;Nam-Soo Hong;Jun Hyun Hwang;Jaeyoung Ha
    • Journal of agricultural medicine and community health
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    • v.49 no.1
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    • pp.13-36
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    • 2024
  • Objectives: The purpose of this field case report is 1) to analyze the community's strategy and performance in responding to infectious diseases through the case of COVID-19 infectious disease crisis response of Daegu Metropolitan City, and 2) to interpret this case using governance theory and infectious disease response governance framework. and 3) to propose a strategic model to prepare for future infectious disease outbreaks of the community. Methods: Cases of Daegu Metropolitan City's infectious disease crisis response were analyzed through researchers' participatory observations. And review of OVID-19 White Paper of Daegu Metropolitan City, Daegu Medical Association's COVID-19 White Paper, and literature review of domestic and international governance, and administrative documents. Results: Through the researcher's participatory observation and literature review, 1) establishment of leadership and response system to respond to the infectious disease crisis in Daegu Metropolitan City, 2) citizen's participation and communication strategy through the pan-citizen response committee, 3) cooperation between Daegu Metropolitan City and governance of public-private medical facilities, 4) decision-making and crisis response through participation and communication between the Daegu Metropolitan City Medical Association, Medi-City Daegu Council, and medical experts of private sector, 5) symptom monitoring and patient triage strategies and treatment response for confirmed infectious disease patients by member of Daegu Medical Association, 6) strategies and implications for establishing and utilizing a local infectious disease crisis response information system were derived. Conclusions: The results of the study empirically demonstrate that collaborative governance of the community through the participation of citizens, private sector experts, and community medical facilities is a key element for effective response to infectious disease crises.

Effects of the Double Cropping System on Wheat Quality and Soil Properties (밀-하작물 작부체계가 밀 품질 및 토양에 미치는 영향)

  • Jisu Choi;Seong Hwan Oh;Seo Young Oh;Tae Hee Kim;Sung Hoon Kim;Hyeonjin Park;Jin-Kyung Cha
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.68 no.4
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    • pp.335-342
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    • 2023
  • To achieve self-sufficiency in domestic wheat (Triticum aestivum L.), an increase in high-quality wheat production is essential. Given Korea's limited land area, the utilization of cropping systems is imperative. Wheat is compatible with a double cropping system along with rice, soybeans, and corn. Data on alterations in wheat quality following summer crop cultivation is required. This study investigated the impact of cultivating preceding crops such as rice, soybeans, and corn in a wheat cropping system. The analysis focused on the influence of these preceding crops on wheat growth, quality, and soil characteristics, elucidating their interrelationships and impacts. While there were no differences in growth timing and quantity during wheat growth, a significant variance was observed in stem length. Protein content, a key quality attribute of wheat, displayed variations based on the intercropped crops, with the highest increase observed in wheat cultivated after soybeans. Soil moisture content also exhibited variations depending on the intercropping system. The wheat-rice intercropping system, which requires soil moisture retention, resulted in greater pore space saturation in comparison to other systems. Moreover, soil chemical properties, specifically phosphorus and calcium levels, were influenced by intercropping. The highest reduction in soil phosphorus content occurred with soybean cultivation. These findings suggest that intercropping wheat with soybeans can potentially enhance wheat quality in domestic varieties.