• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.17 no.1
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• pp.1-12
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• 2007

We have reviewed all cases and epidemiological studies that have reported the association between worker's exposure to metalworking fluids(MWF) and non-malignant respiratory diseases. The followings are main conclusions we critically reviewed. Exposure to MWF was believed to be significantly related to the risk of cough and phlegm. Relative risk caused by straight MWF was found to be higher in exposure to straight MWF than water-soluble MWF. We also found that exposure to water-soluble MWF significantly caused hypersensitivity pneumonitis (HP) and occupational asthma. The main culprits that cause the development of HP and asthma are believed to be microbes contaminated in MWF, ethanolamine and biocides. HP and asthma could be developed at even exposure to lower than $0.5mg/m^3$, exposure level recommended by NIOSH. Most epidemiological studies have reported that relationship between chronic bronchitis and exposure to MWF was significant. Although there were several studies that suggested the significant association between exposure to MWF and the development of rhinitis and sinusitis, we could not conclude the causal relationship because of lack of evidences.

• Tuberculosis and Respiratory Diseases
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• v.80 no.4
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• pp.351-357
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• 2017

In 2011, a cluster of peripartum patients were admitted to the intensive care unit of a tertiary hospital in Seoul with signs and symptoms of severe respiratory distress of unknown etiology. Subsequent epidemiological and animal studies suggested that humidifier disinfectant (HD) might represent the source of this pathology. Epidemiological studies, animal studies, and dose-response analysis demonstrated a strong association between HD use and lung injuries. The diagnostic criteria for HD-associated lung injury (HDALI) was defined on the basis of the clinical, pathological, and radiological attributes of the patients. The clinical spectrum of HDALI appears to range from asymptomatic to full-blown acute respiratory failure, and some patients have required actual lung transplantation for survival. The overall mortality of the exposed population was not significant, although peripartum patients and children who were admitted to the intensive care unit did show high mortality rates. Persistent clinical findings such as diffuse ill-defined centrilobular nodules and restrictive lung dysfunction were observed in some of the survivors. The findings of this review emphasize the importance of assessment of the level of toxicity of chemical inhalants utilized in a home setting, as well as the need to identify and monitor afflicted individuals after inhalational injury.

• Journal of the Korean Society for Library and Information Science
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• v.50 no.2
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• pp.271-287
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• 2016

This study intends to review the quality factors of library service for the disabled using user-centered approach. For the empirical review of quality factors, Nine quality factors were drawn after analyzing the current library service quality factors and the standards of library service for the disabled. Using these factors, The survey for identifying importance of factors and the qualitative evaluation of service cases were performed in this study. As a result of this survey, the most critical but relatively weak quality factors were facility, collection and staff factors. And the qualitative evaluation results of service cases indicated that the reading culture program and the information service factors were critical.

• Tuberculosis and Respiratory Diseases
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• v.73 no.1
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• pp.1-10
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• 2012

Care of patients with sepsis has improved over the last decade. However, in the recent two years, there was no significant progress in the development of a new drug for critically ill patients. In January 2011, it was announced that the worldwide phase 3 randomized trial of a novel anti-Toll-like receptor-4 compound, eritoran tetrasodium, had failed to demonstrate an improvement in the mortality of patients with severe sepsis. In October 2011, Xigris (drotrecogin alfa, a recombinant activated protein C) was withdrawn from the market following the failure of its worldwide trial that had attempted to demonstrate improved outcome. These announcements were disappointing. The recent failure of 2 promising drugs to further reduce mortality suggests that new approaches are needed. A study was published showing that sepsis can be associated to a state of immunosuppression and loss of immune function in human. However, the timing, incidence, and nature of the immunosuppression remain poorly characterized, especially in humans. This emphasizes the need for a better understanding of sepsis as well as new therapeutic strategies. Many clinical experiences of the extracorporeal membrane oxygenator (ECMO) treatment for adult acute respiratory distress syndrome (ARDS) patients, which is caused by the H1N1 influenza A virus, were reported. The use of ECMO in severe respiratory failure, particularly in the treatment of adult ARDS, is occurring more commonly.

• Computers and Concrete
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• v.24 no.5
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• pp.453-458
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• 2019

Today, concrete remains the most important, durable, and reliable material that has been used in the construction sector, making it the most commonly used material after water. However, cement continues to exert many negative effects on the environment, including the production of carbon dioxide (CO2), which pollutes the atmosphere. Cement production is costly, and it also consumes energy and natural non- renewable resources, which are critical for sustainability. These factors represent the motivation for researchers to examine the various alternatives that can reduce the effects on the environment, natural resources, and energy consumption and enhance the mechanical properties of concrete. Geopolymer is one alternative that has been investigated; this can be produced using aluminosilicate materials such as low calcium (class F) FA, Ultra-Fine GGBS, and high calcium FA (class C, which are available worldwide as industrial, agricultural byproducts.). It has a high percentage of silica and alumina, which react with alkaline solution (activators). Aluminosilicate gel, which forms as a result of this reaction, is an effective binding material for the concrete. This paper presents an up-to-date review regarding the important engineering properties of geopolymer formed by FA and slag binders; the findings demonstrate that this type of geopolymer could be an adequate alternative to ordinary Portland cement (OPC). Due to the significant positive mechanical properties of slag-FA geopolymer cements and their positive effects on the environment, it represents a material that could potentially be used in the construction industry.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.04a
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• pp.109-112
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• 2011

The result of design review and arrangement of a combustion chamber test facility(CTF) and a turbo-pump real propellant test facility(TPTF) is briefly described. The development/qualification tests of combustion chamber and turbo-pump for 75ton-class liquid rocket engine will be performed in CTF and TPTF. The critical design of hydraulic-pneumatic system, control and data acquisition system, test stand cell, and auxiliary facilities in CTF and TPTF was performed.

• Ocean Systems Engineering
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• v.12 no.3
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• pp.301-333
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• 2022

Herein, we report meaningful and selective review of the progress made on 'Vortex Induced Vibration (VIV)' and 'Vortex Induced Motion (VIM)' of 'Structures of Specific Shapes (SoSS)' subjected to steady uniform flow and of relevance to/in marine structures. Important and critical elements of the numerical methods, experimental methods, and physical ideas are listed and analysed critically and the limitations of the current state of art of VIV/VIM are discussed in-detail. Our focus and aim are to analyse the existing researches with respect to the application in analyses, design and production of marine structures and the reported reviews centre on these only. We identify the critical and important issues that exist in the current literature and utilise these issues to highlight the challenges that need to be tackled to design and develop new age marine structures that can exist and operate safely in the areas of dominance by the VIV/VIM. Finally, we also identify some areas for future scope of research on VIV/VIM.

• International conference on construction engineering and project management
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• 2020.12a
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• pp.409-416
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• 2020

This paper proposes a study measuring productivity improvement by using a type of technology called "Machine Guidance" through work sampling in earthwork. Earthwork is the activity typically on the critical path, indicating that productivity for the activity is critical for managing schedule on time. Thanks to the development of sensing and information system technologies, productivity for earthwork has been improved. While there have been many studies investigating the application of a certain type of technology to earthwork, few studies have measured the productivity improvement and presented how the technology leads to productivity improvement. Based on the thorough literature review, it is hypothesized that Machine Guidance contributes to improving productivity of earthwork by reducing indirect workhours spent for information waiting and inspection. In addition to the literature review, this paper presents a research model to test the hypothesis by using the work sampling technique. By proving and quantifying the productivity improvement from the technology use, this study can help practitioners justify the investment for technology use, which will contribute to the deployment of technology and more effective execution of earthwork.

• Journal of Sensor Science and Technology
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• v.32 no.6
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• pp.340-351
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• 2023

Wearable sensors designed for strain, pressure, and temperature measurements are essential for monitoring human movements, health status, physiological data, and responses to external stimuli. Notably, recent research has led to the development of high-performance wearable sensors using innovative materials and device structures that exhibit ultra-high sensitivity compared with their commercial counterparts. However, the quest for accurate sensing has identified a critical challenge. Specifically, the mechanical flexibility of the substrates in wearable sensors can introduce interference signals, particularly when subjected to varying external stimuli and environmental conditions, potentially resulting in signal crosstalk and compromised data fidelity. Consequently, the pursuit of non-interference sensing technology is pivotal for enabling independent measurements of concurrent input signals related to strain, pressure, and temperature, ensuring precise signal acquisition. In this comprehensive review, we present an overview of the recent advances in noninterference sensing strategies. We explore various fabrication methods for sensing strain, pressure, and temperature, emphasizing the use of hybrid composite materials with distinct mechanical properties. This review contributes to the understanding of critical developments in wearable sensor technology that are vital for their ongoing application and evolution in numerous fields.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.63-64
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• 2023

Indoor Air Quality is crucial in hospital projects to ensure the health and safety of patients, staff, and visitors. The research methodology comprises an comprehensive literature review, then a comprehensive questionnaire survey conducted among stakeholders involved in Vietnamese hospital projects. 15 variables were identified and categorized into four distinct groups, elucidating their influence on the adoption of advanced IAQ-enhancing technology. This study uses factor analysis, a mean score method and hypothesis test to analyze the factor result from the survey. two-step process, including an in-depth literature review and questionaire survey. The study's findings culminated in the ranking, examination, and categorization of these 15 variables, which were clustered into four essential categories: economic factors, design elements, governance strategies, and technical requirements. Additionally, the research explored viable solutions to improve indoor air quality in Vietnam's unique environmental context, examining the factors that impact the selection of such solutions. The study's outcomes yield practical recommendations for architects, engineers, and hospital administrators in enhancing IAQ within healthcare facilities. Furthermore, it presents a framework attuned to local environmental factors and building materials, contributing significantly to the existing body of knowledge on IAQ within hospital projects, particularly in the Vietnamese context.