• Journal of the Korean Society for Nondestructive Testing
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• v.32 no.6
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• pp.648-660
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• 2012

Reliable response measurements are extremely important for proper bridge health monitoring but incomplete and unreliable data may be acquired due to sensor problems and environmental effects. In the case of a sensor malfunction, parts of the measured data can be missing so that the structural health condition cannot be monitored reliably. This means that the dynamic characteristics of natural frequencies can change as if the structure is damaged due to environmental effects, such as temperature variations. To overcome these problems, this paper proposes a systematic procedure of data analysis to recover missing data and eliminate the environmental effects from the measured data. It also proposes a health index calculated statistically using revised data to evaluate the health condition of a bridge. The proposed method was examined using numerically simulated data with a truss structure and then applied to a set of field data measured from a cable-stayed bridge.

• Journal of Environmental Health Sciences
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• v.49 no.6
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• pp.362-371
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• 2023

Background: PM_2.5 pollution has been a persistent problem in South Korea, with concentrations consistently exceeding World Health Organization (WHO) guidelines. The aging of the population in the country further exacerbates the health impacts of PM_2.5 since older adults are more susceptible to the adverse effects of air pollution. Objectives: This study aims to evaluate how the health impact (premature death) due to long-term exposure to PM_2.5 in South Korea could change in the future according to the trend of change in the country's population structure. Methods: The study employs a relative risk function, which accounts for age-specific relative risks, to assess the changes in premature deaths by age and region at the average annual PM_2.5 concentration for 2022 and at PM_2.5 concentration improvement levels. Premature deaths were estimated using the Global Exposure Mortality Model (GEMM). Results: The findings indicate that the increase in premature deaths resulting from the projected population structure changes up to 2050 would significantly outweigh the health benefits (reduction in premature deaths) compared to 2012. This is primarily attributed to the rising number of premature deaths among the elderly due to population aging. Furthermore, the study suggests that the effectiveness of the current domestic PM_2.5 standard would be halved by 2050 due to the increasing impact of population aging on PM_2.5-related mortality. Conclusions: The study highlights the importance of considering trends in population structure when evaluating the health benefits of air pollution reduction measures. By comparing and evaluating the health benefits in reflection of changes in population structure to the predicted PM_2.5 concentration improvements at the provincial level, a more comprehensive assessment of regional air quality management strategies can be achieved.

• Structural Engineering and Mechanics
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• v.87 no.3
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• pp.211-219
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• 2023

The structural health of a pipeline is usually assessed by visual inspection. In addition to the fact that this method is expensive and time consuming, inspection of the whole structure is not possible due to limited access to some points. Therefore, adopting a damage detection method without the mentioned limitations is important in order to increase the safety of the structure. In recent years, vibration-based methods have been used to detect damage. These methods detect structural defects based on the fact that the dynamic responses of the structure will change due to damage existence. Therefore, the location and extent of damage, before and after the damage, are determined. In this study, fuzzy genetic algorithm has been used to monitor the structural health of the pipeline to create a fuzzy automated system and all kinds of possible failure scenarios that can occur for the structure. For this purpose, the results of an experimental model have been used. Its numerical model is generated in ABAQUS software and the results of the analysis are used in the fuzzy genetic algorithm. Results show that the system is more accurate in detecting high-intensity damages, and the use of higher frequency modes helps to increase accuracy. Moreover, the system considers the damage in symmetric regions with the same degree of membership. To deal with the uncertainties, some error values are added, which are observed to be negligible up to 10% of the error.

• Smart Structures and Systems
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• v.15 no.2
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• pp.299-314
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• 2015

Submersed rock-berm structures are frequently used for protection of underwater lifelines such as pipelines and power cables. During the service life, the rock-berm structure can experience several accidental loads such as anchor collision. The consequences can be severe with a certain level of frequency; hence, the structural responses should be carefully understood for implementing a proper structural health monitoring method. However, no study has been made to quantify the structural responses because it is hard to deal with the individual behavior of each rock. Therefore, this study presents a collision analysis of the submersed rock-berm structure using a finite element software package by facilitating the smoothed-particle hydrodynamics (SPH) method. The analysis results were compared with those obtained from the Lagrange method. Moreover, two types of anchors (stock anchor and stockless anchor), three collision points and two different drop velocities (terminal velocity of each anchor and 5 m/s) were selected to investigate the changes in the responses. Finally, the effect of these parameters (analysis method, anchor type, collision point and drop velocity) on the analysis results was studied. Accordingly, the effectiveness of the SPH method is verified, a safe rock-berm height (over 1 m) is proposed, and a gauge point (0.5 m above the seabed) is suggested for a structural health monitoring implementation.

• Smart Structures and Systems
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• v.4 no.3
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• pp.305-318
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• 2008

The development of a digital signal processor based prototype is described in relation to continuing efforts for realizing a fully self-contained active sensor system utilizing impedance-based structural health monitoring. The impedance method utilizes a piezoelectric material bonded to the structure under observation to act as both an actuator and sensor. By monitoring the electrical impedance of the piezoelectric material, insights into the health of the structured can be inferred. The active sensing system detailed in this paper interrogates a structure utilizing a self-sensing actuator and a low cost impedance method. Here, all the data processing, storage, and analysis is performed at the sensor location. A wireless transmitter is used to communicate the current status of the structure. With this new low cost, field deployable impedance analyzer, reliance on traditional expensive, bulky, and power consuming impedance analyzers is no longer necessary. A complete power analysis of the prototype is performed to determine the validity of power harvesting being utilized for self-containment of the hardware. Experimental validation of the prototype on a representative structure is also performed and compared to traditional methods of damage detection.

• Journal of the Korea Safety Management & Science
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• v.5 no.2
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• pp.1-10
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• 2003

The discussion for the structure of the intergrated management system(IMS) isbeing made process vigorously in the time of industrial standard in this study. Therefore, safety, health, environment management system was compared, the management method was found, and task standard and object were selected. The structure of database will be possible to prevent industrial injury and environment pollution prevention.

• Journal of Agricultural Extension & Community Development
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• v.30 no.4
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• pp.187-197
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• 2023

The study aims to identify factors related to landscape structure and socioeconomic characteristics that influence adults' physical activity and health. The study analyzes data from 148,643 respondents from the Korea Community Health Survey conducted in 2021. The study measures various factors, including the frequency of physical activity, stress, depression, and landscape metrics of forest patches. Hierarchical multiple regression analysis was used, controlling for socio-demographic characteristics. Larger forest patches and more irregular shapes are associated with higher levels of physical activity among adults. The percentage and area of the forest patch are associated with fewer mental health complaints. Configuration-related landscape metrics such as shape or arrangement of the forest patch did not show a significant association with physical activity. Overall, the study provides insights into how specific characteristics of forest patches in urban areas may influence physical activity and mental health among adults. It emphasizes the importance of green spaces and their potential positive effects on both physical and mental well-being.

• Health Policy and Management
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• v.31 no.3
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• pp.301-311
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• 2021

Background: This study purposed to analyze the relationship between the local extinction index and medical service uses of chronic diseases. The local extinction index is an indicator of the demographic structure and population aging of the region. Methods: The 2014-2018 statistics of National Health Insurance Corporation and Korean Statistical Information Service data were used for the analysis. First, descriptive statistics were used to analyze the general status of research variables. Second, a panel analysis was performed to analyze the relationship between the local extinction index and medical service uses of chronic diseases (hypertension, diabetes mellitus, periodontal disease, arthritis, mental health, epidemic disease, liver disease). Medical service uses were measured by the number of visits/inpatient days and medical charges of seven chronic diseases. Results: Panel analysis results showed that higher local extinction risks (meaning lower local extinction index) had a positive relationship with the number of visits/inpatient days and medical charges of chronic diseases. But the relationships were varied when the seven chronic diseases were analyzed separately. Conclusion: This study showed a significant relationship between the local demographic structure and medical service uses of chronic disease. Analyzing the local demographic structure will be an essential prerequisite step for implementing appropriate regional health care policies.

• The Journal of Korean Medical History
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• v.28 no.1
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• pp.1-10
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• 2015

This study examines the meaning of medical-text publication in the Joseon Dynasty by applying anthropological notions of "health care system" and "popular health care sector" to the social and political contexts of the pre-modern state. The present study focuses on the social network of senders and receivers in which medical knowledge is communicated and shared. Exploring the multi-layered structure of the network among the state, the author-practitioners, and populace, this study argues that the network of knowledge sharing system by publication of medical texts itself is a core structure in the health care system of the Joseon Dynasty. This pre-modern health care system aimed to vitalize and reinforce the "popular health care sector" by sharing medical knowledge with populace through the book-publication system. Foucault's notion of "biopolitics" provides a comparative window between the modern health care system and the health care system of the Joseon period, articulating the particularity of the pre-modern health care system.

• Journal of The Korea Institute of Healthcare Architecture
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• v.20 no.4
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• pp.57-65
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• 2014

Purpose : Mental health service desire has been diversified according to the increase of economic level and rapid social change. Mental Health and Welfare Center(MHWC) is a provider of mental health services in Japan. This is a basic stage study which will suggest the architectural planning guidelines for MHWC. Methods : Data were collected through literature research, field surveys, and expert interviews to 69 MHWC in Japan. 1) Research for the policy and legal aspects of mental health support system. 2) Research for structural aspects of MHWC: Characteristics of establishment, management, and regional factors. 3) Research for the physical environment aspects of MHWC: Classification and evaluation of MHWC's Type by locational characteristics in Japan. Results : The result of this study can be summarized into three points. The first one, Mental Health and Welfare Center's service has being expanded to suicide, depression and stress from chronic mental illness, to reflect social needs. The second one, The average population of area installed at Mental Health and Welfare Center was 2,307,570 person, and average area of the regions were $5,745m^2$. The third one, Mental Health and Welfare Center is divided into single-structure type and combine-structure type. And combine-structure type is divided into medical-combine type, welfare-combine type, and public-combine type.