Sites In Korea Research Articles

Analysis of changes before and after forest fires with LAI, NDVI and ET time series: Focusing on major forest fires in Korea

This study investigates the changes caused by forest fires and the following recovery processes, targeting four forest fire sites in Korea. The time series of two vegetation indices, leaf area index (LAI) and normalized difference vegetation index (NDVI) are investigated along with evapotranspiration (ET) time series for the study objectives. The analysis results show that LAI is most sensitive to burn severity and burned area with its change ranging from 40 % to 70 %, while the changes of NDVI and ET remain 30 % and 20 %, respectively, regardless of forest fire sites. The recovery time from forest fire also varies according to indices: the recovery time is estimated to be about 15 years when considering LAI and NDVI, while just 5 years when considering ET. Overall, LAI seems better to analyze the change in vegetation before and after forest fires. Different vegetation shift patterns after the forest fire are also noticed, mostly from evergreen needleleaf trees to deciduous broadleaf trees. However, it is also found that bad soil fertility condition and artificial afforestation help to maintain the evergreen needleleaf trees after the forest fire.

Assessing COVID-19 Vulnerability Among HIV-positive Men Who Have Sex With Men in Korea: The Role of Vaccination and Sexual Behaviors.

Comorbidities increase susceptibility to severe coronavirus disease 2019 (COVID-19) infections, but limited information has been published regarding human immunodeficiency virus (HIV) and COVID-19 co-infections. This study explored the relationships among socioeconomic characteristics, sexual behaviors, and COVID-19 infection rates among Korean men who have sex with men (MSM) who are also living with HIV. Data were collected through a web survey aimed at members of the largest gay portal site in Korea, supported by the National Research Foundation of Korea (n=1005). The primary independent variables included COVID-19-related vaccinations and sexual behaviors. The dependent variable was the incidence of COVID-19 infection among respondents during the pandemic. For statistical analysis, hierarchical multiple logistic regression was performed, controlling for potential confounding variables. Model I indicated that older MSM were less likely to contract COVID-19 (adjusted odds ratio [aOR], 0.98; 95% confidence interval [CI], 0.96 to 0.99). Model II demonstrated that HIV-positive MSM were nearly twice as likely to be infected with COVID-19 compared to their HIV-negative counterparts (aOR, 1.97; 95% CI, 1.14 to 3.41). Furthermore, even after accounting for COVID-19 vaccination status in model III, HIV-positive MSM continued to show a higher risk of infection (aOR, 1.93; 95% CI, 1.12 to 3.35). The findings of this study indicate that HIV-positive MSM are at an increased risk of contracting COVID-19, even when their vaccination status is considered. Therefore, it is essential to prioritize the prevention of COVID-19 infections in HIV-positive individuals by administering appropriate antiretroviral therapy and ensuring adherence to public health guidelines.

Probabilistic typhoon hazard and sensitivity analysis for nuclear power plant sites in Korea using logic tree

There has been an increase in typhoon intensity, and high-intensity typhoons can affect the safety of nuclear power plants (NPPs). Typhoons can damage the structures, systems, and components (SSCs) of NPPs, causing core damage and the release of radioactive materials into the environment. Therefore, design criteria for the effects of natural phenomena are demanded to ensure the safety-critical SSC functions of NPPs. Also, there is a need for safety assessments of typhoons in operational NPPs, which require typhoon hazard analysis. In this study, we derived typhoon hazards for NPPs in Korea using Logic Tree and Monte Carlo simulations. We performed sensitivity analysis on the typhoon hazards based on the distances (up to 100 km) from the NPP sites. Among other NPP sites, the typhoon hazard of the Kori site showed the highest wind speed, and the Hanul site showed the lowest wind speed. The uncertainty of the wind speed increased as the recurrence interval of the typhoon hazard increased. We compared the typhoon hazard in the areas of interest to that within 100 km. The range of the distance deviation for the Hanbit site's typhoon hazard was within μ±σ up to 75 km, while for the other sites, it was within μ±σ up to 100 km.

Deep neural network-based probabilistic classifier of occupational accident types on a construction site in Korea

ABSTRACT The number of accidents in the Korean construction industry has been increasing rapidly, reaching about 25,000 every year. Although strong and binding laws and systems have been implemented to reduce accidents in the construction industry, the frequency of accidents is still higher than that of other industries. While existing studies have provided models for predicting occupational accidents, there are limitations in predicting individual workers’ occupational accidents specific to site conditions and worker tasks. This study proposed a deep neural network model that can classify and predict core accident types for workers in construction sites, considering the characteristics of the site and workers based on 70,204 case data from the Korea Occupational Safety and Health Agency. The result of this study would contribute to improve safety in construction sites by being used for safety accident prevention training customized for workers at construction sites. Additionally, the model can be expanded to develop a real-time construction site occupational accident monitoring and early warning system by integrating ICT-based safety management technologies such as wearable devices and CCTV.

Intravascular Imaging and Angiography Guidance in Complex Percutaneous Coronary Intervention Among Patients With Diabetes

Data are limited regarding the effects of intravascular imaging guidance during complex percutaneous coronary intervention (PCI) in patients with diabetes. To compare the clinical outcomes of intravascular imaging-guided vs angiography-guided complex PCI in patients with or without diabetes. This prespecified secondary analysis of a subgroup of patients in RENOVATE-COMPLEX-PCI (Randomized Controlled Trial of Intravascular Imaging Guidance Versus Angiography-Guidance on Clinical Outcomes After Complex Percutaneous Coronary Intervention), an investigator-initiated, open-label multicenter trial, analyzed enrolled patients who underwent complex PCI at 20 sites in Korea from May 2018 through May 2021. Eligible patients were randomly assigned in a 2:1 ratio to undergo either the intravascular imaging-guided PCI or angiography-guided PCI. Data analyses were performed from June 2023 to April 2024. Percutaneous coronary intervention was performed either under the guidance of intravascular imaging or angiography alone. The primary end point was target vessel failure (TVF), defined as a composite of cardiac death, target vessel-related myocardial infarction, or target vessel revascularization. Among the 1639 patients included in the analysis (mean [SD] age, 65.6 [10.2] years; 1300 males [79.3%]), 617 (37.6%) had diabetes. The incidence of TVF was significantly higher in patients with diabetes than patients without diabetes (hazard ratio [HR], 1.86; 95% CI, 1.33-2.60; P < .001). Among patients without diabetes, the intravascular imaging-guided PCI group had a significantly lower incidence of TVF compared with the angiography-guided PCI group (4.7% vs 12.2%; HR, 0.41 [95% CI, 0.25-0.67]; P < .001). Conversely, in patients with diabetes, the risk of TVF was not significantly different between the 2 groups (12.9% vs 12.3%; HR, 0.97 [95% CI, 0.60-1.57]; P = .90). There was a significant interaction between the use of intravascular imaging and diabetes for the risk of TVF (P for interaction = .02). Among patients with diabetes, only those with good glycemic control (hemoglobin A1c level ≤7.5%) and who achieved stent optimization by intravascular imaging showed a lower risk of future ischemic events (HR, 0.31; 95% CI, 0.12-0.82; P = .02). In this secondary analysis of a subgroup of patients in the RENOVATE-COMPLEX-PCI trial, intravascular imaging guidance reduced the risk of TVF compared with angiography guidance in patients without diabetes (but not in patients with diabetes) during complex PCI. In patients with diabetes undergoing complex PCI, attention should be paid to stent optimization using intravascular imaging and glycemic control to improve outcomes. ClinicalTrials.gov Identifier: NCT03381872.

Potential of secondary metabolites from soil-derived actinomycetes as juvenile hormone disruptor and insecticides

Actinomycetes represent sources of potential alternatives to chemicals as biological pest control agents, and several actinomycetes are known to produce metabolites with insecticidal activities against insect pests. Although these metabolites are eco-friendly and effective, it is necessary to identify a novel insect-specific insecticidal agents that can minimize the occurrence of resistance. Thus, in this study, we screened the juvenile hormone disruptor (JHD) and insecticidal activities of crude acetone extracts derived from various actinomycetes as novel biopesticide candidates. A total of 300 soil-derived actinomycetes were isolated from various sites in Korea, and were screened for their JHD and insecticidal activities against a range of important medical and agricultural pests. Among them, eight extracts showed high levels of JHD activity. The AN120590 strain showed a broad insecticidal spectrum with stably maintained JHD properties. Additionally, the dead larvae of Aedes albopictus and Plutella xylostella treated with acetone extracts of the AN120590 strain displayed morphological deformities similar to those of insects treated with juvenile hormone-based insect growth regulators (IGRs). These findings indicate that actinomycetes represent promising sources of novel IGRs that can be effectively applied as insecticides with a broad insecticidal spectrum.

Spatial variation of airborne bacterial heterogeneity and potential opportunistic human pathogens: a comparative study of sites in Korea and Japan

Spatial variation of airborne bacterial heterogeneity and potential opportunistic human pathogens: a comparative study of sites in Korea and Japan

Intravascular Imaging–Guided Optimization of Complex Percutaneous Coronary Intervention by Sex

There have been heterogeneous results related to sex differences in prognosis after percutaneous coronary artery intervention (PCI) for complex coronary artery lesions. To evaluate potential differences in outcomes with intravascular imaging-guided PCI of complex coronary artery lesions between women and men. This prespecified substudy evaluates the interaction of sex in the investigator-initiated, open-label, multicenter RENOVATE-COMPLEX-PCI randomized clinical trial, which demonstrated the superiority of intravascular imaging-guided PCI compared with angiography-guided PCI in patients with complex coronary artery lesions. The trial was conducted at 20 sites in Korea. Patients with complex coronary artery lesions undergoing PCI were enrolled between May 2018 and May 2021, and the median (IQR) follow-up period was 2.1 (1.4-3.0) years. Data were analyzed from December 2022 to December 2023. After diagnostic coronary angiography, eligible patients were randomly assigned in a 2:1 ratio to receive intravascular imaging-guided PCI or angiography-guided PCI. The choice and timing of the intravascular imaging device were left to the operators' discretion. The primary end point was target vessel failure, defined as a composite of cardiac death, target vessel-related myocardial infarction, or clinically driven target vessel revascularization. Secondary end points included individual components of the primary end point. Of 1639 included patients, 339 (20.7%) were women, and the mean (SD) age was 65.6 (10.2) years. There was no difference in the risk of the primary end point between women and men (9.4% vs 8.3%; adjusted hazard ratio [HR], 1.39; 95% CI, 0.89-2.18; P = .15). Intravascular imaging-guided PCI tended to have lower incidence of the primary end point than angiography-guided PCI in both women (5.2% vs 14.5%; adjusted HR, 0.34; 95% CI, 0.15-0.78; P = .01) and men (8.3% vs 11.7%; adjusted HR, 0.72; 95% CI, 0.49-1.05; P = .09) without significant interaction (P for interaction = .86). In patients undergoing complex PCI, compared with angiographic guidance, intravascular imaging guidance was associated with similar reduction in the risk of target vessel failure among women and men. The treatment benefit of intravascular imaging-guided PCI showed no significant interaction between treatment strategy and sex. ClinicalTrials.gov Identifier: NCT03381872.

Masculinity, Rather Than Biological Sex, Is Associated With Psychological Comorbidities in Patients With Irritable Bowel Syndrome.

Irritable bowel syndrome (IBS) generally shows sex differences, and psychiatric comorbidities play an important role in its pathogenesis. We aim to measure the levels of gender roles and investigate their relationship with psychiatric factors in patients with IBS versus healthy controls. Patients diagnosed with IBS by Rome III and whose colonoscopy findings were normal were enrolled at multiple sites in Korea. The participants completed the Korean Sex Role Inventory-Short Form (KSRI-SF) to assess masculinity and femininity, the stress questionnaire, the Hospital Anxiety Depression Scale (HADS), and the 36-item Short Form Health Survey questionnaire to assess the quality of life (QOL). In total, 102 patients with IBS (male:female = 35:67; mean age 42.6 ± 16.7 years) and 55 controls (male:female = 20:35; mean age 42.4 ± 11.1 years) were recruited. IBS patients had higher stress (9.69 ± 8.23 vs 4.56 ± 8.31, P < 0.001) and HADS scores (16.12 ± 7.17 vs 10.22 ± 5.74, P < 0.001) than the control group, but showed no significant difference in KSRI-SF scores. No significant differences in HADS and KSRI-SF scores were found between males and females. However, IBS patients whose symptoms worsened due to stress and patients with anxiety or depression had significantly lower masculinity. QOL was poorer in IBS patients than in controls. In stepwise multivariate analyses, the anxiety score, depression score, and the degree of daily life disturbance, not masculinity, were associated with the QOL of IBS patients. IBS patients had higher stress, more psychiatric comorbidities, and lower QOL than controls. Low masculinity, rather than sex, was associated with stress and psychological comorbidities, which deteriorated the QOL in IBS patients.

The effect of the authenticity of the Catholic pilgrimage site on spiritual well‐being and quality of life of pilgrims

AbstractWith the growing interest in spirituality, there has been a corresponding rise in the number of pilgrimages. Modern pilgrims embark on pilgrimages not only for religious purposes but also for their own mental peace and health. To enhance our understanding of this trend we conducted an empirical survey of pilgrims visiting Saenamteo Catholic Martyrs' Shrine, a representative martyrdom site in Korea located on the Seoul Catholic Pilgrimage Route, the first Vatican‐designated international pilgrimage site in Asia. The analysis showed that the authenticity of the pilgrimage site impacts both the religious and the existential aspects of spiritual well‐being. However, while the existential aspect of spiritual well‐being impacted on quality of life, the religious well‐being was insignificant. These results indicate that modern pilgrims feel that their happiness and health, rather than their religion directly affects their quality of life.

Prediction Model for Annual Variation in Total Pollen by Allergenic Trees in Korean Cities.

Pollen forecasting systems can provide information for coping with respiratory allergies. They estimate daily pollen production, dispersal, deposition, and removal based on daily weather conditions to predict daily pollen concentrations and provide allergy warnings. As of 2023, the Korea Meteorological Administration (KMA) provides 2-day forecast of allergenic pollens. However, unlike these models, long-term analysis of annual observations of tree pollen reveal annual variations. Therefore, in this study, we aimed to develop annual prediction models for allergenic tree pollens based on long-term multi-site pollen and meteorological data. Daily pollen concentrations were observed using Hirst-type volumetric spore traps at nine sites in Korea from 1998 to 2021, and daily weather data from the closest KMA stations were utilized. Models were developed to predict the seasonal pollen integral of seven tree species based on monthly mean temperature, wind speed, and total precipitation using three variable selection methods: 1) the t-test based key variable screening followed by linear regression with stepwise procedure (TM), 2) direct linear regression with stepwise procedure from the full variable model (FM), and 3) LASSO regression from the full variable model (LM). Data obtained during 1998-2017 and 2018=2021 were utilized for model development and validation, respectively. The root mean squared error, mean absolute error, mean error, and coefficient of determination (R²) revealed that the TM models were best suited for actual forecasting, even though R² in the TM model was lower than those of the FM and LM models. The annual variation model in this study can be integrated with the daily pollen forecast model by controlling the annual pollen potential, and the accuracy of the daily forecast can be improved accordingly.

Water-rock interactions of uranium deposits: A field investigation and laboratory batch experiment

Interactions between bedrock and groundwater in the far-field of a deep geological repository (DGR) for high-level radioactive waste significantly affect the transport of uranium, which is the major radionuclide in a DGR. Therefore, the present study evaluated the geochemical behavior of uranium by assessing the hydrogeochemical characteristics of groundwater, surface water, mine water, and quarry runoff water in the Okcheon metamorphic belt, which represents a natural analogue study site in Korea. A batch experiment was also conducted to further elucidate the interactions between the uranium-containing rock and groundwater in the study area. The results of the field investigation indicated that uranium in groundwater formed aqueous complexes in the form of calcium uranyl tricarbonate. The concentrations of uranium in groundwater were low, at less than 1 μg L−1, which seems to be attributable to the dissolutions of uraninite, coffinite, UO2(am), and U4O9(c) under the moderately reduced condition and subsequent control by co-precipitation with iron (hydr)oxides. The results of the batch experiment showed that uranium concentrations may be controlled by adsorption or surface complexation with iron oxides. The field study demonstrates the equilibrium state maintained in the current geochemical conditions at the study site, while the batch experiment provides implications regarding the reaction processes over time. Overall, this study showed that uranium forms complexes with carbonate and sulfate under the geochemical conditions of the study site, and that its mobility could be restricted through co-precipitation or adsorption/surface complexation. This study is expected to contribute to a comprehensive understanding of how the behavior of uranium is affected by the evolution of geochemical conditions around the DGR.

Ecosystem service evaluation based on local knowledge of residents using spatial text-mining

This study aims to evaluate the ecosystem services of Upo wetland, one of the best-known Ramsar sites in Korea, reflecting the characteristics of the ecological assets and local knowledges in the area. Application of spatial text-mining begins with collecting local perceptions and knowledge of residents on the 17 ecological assets of Upo site and surrounding area. Our results identified five important ecosystem services: flood control during heavy rainfall, water purification by aquatic plants, cultural and natural heritages, agricultural products and water provision for crop cultivation. GIS created a map where these ecosystem services were linked to the locations of 17 ecological assets. This map showed which ecosystem service is associated with particular ecological assets and their characteristics from residents’ perspectives. Mapping local knowledge using the spatial text-mining is able to identify multi-functional bases which provide various ecosystem services in the same location simultaneously. Identification of multi-functional bases can provide information for local government to design an effective and comprehensive management plan considering physical-cultural geography of ecosystem services.

Development of Ethyl Formate Disinfestation Treatment Methods for the Prevention of the Introduction and Establishment of Exotic Insect Pests in Greenhouse Cultivation

Globalization has increased international trade and caused an annual increase in the number of non-native insect pest species found in quarantine sites in Korea. Since over 80% of Korean farms use greenhouses with internal conditions conducive to growing crops and hospitable to exotic pests, efficient pest control is crucial. This study evaluated the efficacy of ethyl formate (EF) against three major exotic insect pests (Aphis gossypii, Frankliniella occidentalis, and Tetranychus urticae) and beneficial organisms (earthworms, honeybees, and silkworms) via EF fumigation experiments at two concentrations. The lethal concentration–time (LCt)99 values of A. gossypii, F. occidentalis, and T. urticae were 8.96, 14.00, and 19.07 g h/m3, respectively. Four hours of fumigation of EF at 15 g/m3 left no residue on the crops or soil after a maximum of 3 h. The beneficial organisms exhibited higher tolerance levels than A. gossypii with regard to LCt99 value, but the higher EF treatment dosage needed to control F. occidentalis and T. urticae could be highly lethal to honeybees. The lower EF dose (4 g/m3) effectively controlled A. gossypii, but 15 g/m3 was needed for F. occidentalis and T. urticae. Phytotoxicity varied in severity with EF concentration. These insights can help in developing a refined disinfestation strategy for greenhouses.

Discordance between quantitative coronary angiography and fractional flow reserve or intravascular ultrasound: a substudy of the FLAVOUR trial

Abstract Background Discrepancies between quantitative coronary angiography (QCA) and fractional flow reserve (FFR) or intravascular ultrasound (IVUS) are often observed in coronary lesions with intermediate stenosis. Objectives We investigated the impact of physiology- or intracoronary imaging-directed revascularization strategies on clinical outcomes in patients with discordant coronary lesions between QCA and FFR or IVUS. Methods This study was a post hoc analysis of the FLAVOUR study, an investigator-initiated, prospective, randomized, open-label, multinational trial performed at 18 sites in Korea and China. In the FLAVOUR study, 200 patients with ≥60% diameter stenosis (DS) deferred percutaneous coronary intervention (PCI) according to FFR &amp;gt; 0.8 (n=141) or a minimal lumen area &amp;gt; 3 mm2 or 3-4 mm2 with a plaque burden &amp;lt;70% on IVUS whereas 351 patients with &amp;lt;60% DS performed PCI according to positive FFR (n=118) or positive IVUS (n=233) results. The primary outcome was a patient-oriented composite outcome (POCO), a composite of death, myocardial infarction, or revascularization. Results The incidence of discordance was 28.1% in the FFR group and 32.4% in the IVUS group. At 24 months, among patients with ≥60% DS, the incidence of POCO was similar between FFR-guided and IVUS-guided deferral strategies (4.4% vs. 3.4%, p=0.757). Among patients with &amp;lt;60% DS, FFR-directed or IVUS-directed PCI did not differ in the POCO incidence (5.2% vs. 2.6%, p=0.207). However, FFR-guided PCI showed a higher incidence of periprocedural myocardial infarction than IVUS-guided PCI in &amp;lt;60% DS lesions (2.6% vs. 0.0%, p=0.014). Conclusions In patients with discordant intermediate stenosis between QCA and FFR or IVUS, physiology- and imaging-directed revascularization strategies are comparable concerning POCO at 24 months.

Differential outcomes in FFR-guided versus angiography-guided revascularization strategy according to target non-infarct related vessels: from FRAME-AMI trial

Abstract Background Incomplete revascularization of non-infarct related arteries (IRA) leads to worse outcomes in patients with acute myocardial infarction (AMI) and multivessel coronary artery disease (MVD). Outcomes of fractional flow reserve (FFR)- and angiography-guided percutaneous coronary intervention (PCI) for non-IRA may differ according to their location between the anterior descending artery (LAD) and non-LAD. Aims We investigated the impact of FFR- versus angiography-guided PCI on clinical outcomes according to the location of non-IRA (LAD versus non-LAD) in AMI patients with MVD. Methods This trial was a pre-specified post-hoc analysis of the FRAME-AMI study, an investigator-initiated, randomized, open-label, multicenter trial at 14 sites in Korea. In the FRAME-AMI trial, PCI was performed for non-IRA in 64.1% (FFR £0.80) and 97.1% (diameter stenosis of &amp;gt;50%) in FFR-guided PCI and angiography-guided PCI groups, respectively. We grouped the patients into four according to treatment strategy (FFR versus angiography) and location of non-IRA (LAD vs. non-LAD). The primary endpoint was a composite of time to death, MI, or repeat revascularization. Results Patients with non-IRA involving LAD and non-LAD were 55.0% and 45.0%, respectively. The proportion of performed PCI (82.2% vs. 78.3%, p=0.242) and the rate of the primary outcome (9.4% vs. 11.5%, p=0.421) were similar between LAD and non-LAD. Among patients with non-IRA involving LAD, the FFR-guided group had a fewer events rate of the primary outcome than the angiography-guided group (5.7% vs. 14.3%, p=0.010). Among those with non-IRA not involving LAD, the FFR-guided group tended to the lower incidence of the primary outcome compared to the angiography-guided group (7.4% vs. 14.5%, p=0.081). However, the effect of the interaction between LAD and non-LAD on the primary outcome was not found (p for interaction 0.667). Conclusions In AMI patients with MVD, FFR-directed PCI for non-IRA was superior to angiography-guided PCI regardless of the location of non-IRA. The benefit of an FFR-directed revascularization strategy for non-IRA is likely enhanced in LAD.

Estimating the transboundary budget of sulfate aerosols in Northeast Asia with NASA MERRA aerosol reanalysis data

Using the Modern-Era Retrospective Analysis for Research and Applications Aerosol (MERRAero) reanalysis data, we conducted an estimation of the impact of transboundary-transported sulfate aerosols from China, specifically the Beijing–Tianjin–Hebei (BTH) region and Shandong province, on the sulfate concentrations in Korea between 2004 and 2020. Our analysis revealed that the ground-level sulfate concentration at six sites in Korea experienced a significant decrease of over 40%, from 7.16 μg m−3 to 3.7 μg m−3 after 2013. The MERRAero reanalysis data provided insights into a yearly reduction of 0.8 μg m−3 in sulfate concentration for the BTH and Shandong regions, while Korea showed an annual decrease of 0.2 μg m−3. Notably, the BTH and Shandong regions and Korea displayed the strongest correlation in sulfate concentrations with a one-day lag, particularly during the winter season. With the exception of summer, approximately 49.79 ton km−2 month−1 of sulfate was transported from the BTH and Shandong regions of China to Korea, resulting in a net increase of 9.8 ton km−2 month−1. The highest influx of sulfate occurred in spring at 70.06 ton km−2 month−1. Despite the clear declining trend in sulfate concentrations across the study region, the transboundary transport of sulfate from the BTH and Shandong regions of China to Korea did not exhibit a decreasing trend. This underscores the importance of thoroughly investigating the formation process of these aerosols through photochemical reactions during their long-distance transportation over northeast Asia, in addition to conducting a comprehensive examination of precursor emissions related to secondary aerosols.

신탁방식 정비사업 신탁수수료율의 영향요인에 관한 연구

Recently, interest and demand for “trust method maintenance projects” are increasing in order to promote stable projects in a number of maintenance projects (planned) areas due to rapid housing supply centered on public redevelopment projects and Moa Town projects in Seoul. The “Trust Method Maintenance Project” was introduced in September 2015 as an amendment to the “Urban and Residential Environment Maintenance Act” to solve the problem of delays in project promotion and lack of expertise. Previous studies mainly discussed how to activate trust method maintenance projects and differences from existing union methods, and studies on the “Trust Fee rate”, a major factor in determining trust methods, are rare. This study derives variables that affect the trust fee rate for the entire domestic trust method maintenance project from January 2016 to December 2021, when the trust method maintenance project was implemented. Based on this, multiple regression analysis analyzed which variables affect the trust fee rate and confirmed that “new total floor area”, “the size of the trust company (small)” and “regional impact (local)” were influencing factors. In other words, it was verified that the size of the project and the degree of risk of the project's progress have an effect on the trust fee rate. This study is significant in that it is the first study on the trust fee rate of trust method maintenance projects that have not been covered in previous studies after investigating the entire trust method maintenance project site in Korea. In the future, this study is expected to be used as a basis for judging the choice of trust method maintenance projects for owners such as unions or land.

Accuracy Evaluation of Real-time Kinematic Positioning Service Based on Digital Multimedia Broadcast Network for Highway Construction Site in Korea

Accuracy Evaluation of Real-time Kinematic Positioning Service Based on Digital Multimedia Broadcast Network for Highway Construction Site in Korea

Identifying Critical Factors and Trends Leading to Fatal Accidents in Small-Scale Construction Sites in Korea

Small-scale construction sites in South Korea account for about 91.5% of all construction workplaces and contribute to 72.3% of the total accidents and fatalities. Safety measures at these sites are often underestimated, and proper safety education is lacking. In particular, the fatality rate is about 4.43 times higher compared to medium-/large-scale construction sites. In this study, a systematic analysis was conducted to examine the causes and trends of industrial accidents in small-scale construction sites to address these issues. This study analyzed industrial accidents in small-scale construction sites using statistical analysis, LDA topic modeling, and network analysis based on data from the Korea Occupational Safety and Health Agency (KOSHA) from 2018 to 2022. The analysis revealed that the most critical cause of accidents in small-scale construction sites is ‘Scaffolding and working platforms’, with accidents primarily involving ‘Fall’. Furthermore, various risk factors and accident trends were identified in apartment construction, new building projects, and mobile scaffolding usage. This study systematically analyzed the causes and trends of industrial accidents at small-scale construction sites, providing important evidence to enhance safety management and preventive measures. The results are expected to play a crucial role in establishing a safety culture at construction sites and ensuring the wellbeing of construction workers.