• Explosives and Blasting
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• v.36 no.4
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• pp.48-61
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• 2018

This case study is concerned with the project of the explosive demolition for the KOGAS office building located in Bundang district in Seongnam city. Since the office building was a kind of long-span beam structures, a mechanical demolition method using jacking support systems was considered in the beginning of the project. With consideration of the excessive reinforcement cost, uncertainty of safety, and prolonged construction period, however, the original plan was later changed to use an explosive demolition method. For the purpose of protecting nearby buildings and facilities during the collapse process, the explosive initiation sequence was elaborately designed to bring down the building structure towards its front left corner. A total of over 550 electronic detonators (Unitronic 600) was used to sequentially initiate the explosives installed at appropriate columns in the first, second, and fifth floors. To diminish dust production, water bags of small and large sizes were respectively installed at each column and on the floors to be blasted. As such, every effort was exercised to mitigate overall noise, dust, and shock vibrations that could be generated during the explosive demolition process for the office building.

• Women's Health Nursing
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• v.25 no.2
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• pp.194-206
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• 2019

Purpose: Maternal Fetal Intensive Care Unit (MFICU), which provides intensive care to high-risk mothers with increasing maternal age and high-risk newborns, has become a new field of nursing work in South Korea. The present study was conducted to identify the educational needs and self-assessing clinical competence of nurses in MFICU. Methods: The education needs and competencies of MFICU nurses were measured through prepared questionnaires by researchers based on the previous studies on job analysis of nurses in MFICU. Data were collected from January 2019 to March 2019. The study involved 168 nurses working in MFICUs at 12 hospitals nationwide as study subjects. The data were analyzed using the SPSS WIN 23.0 program. Results: The education needs of nurses in MFICU had an average of 4.21 points (${\pm}0.50$) and their nursing competence was average 3.38 points (${\pm}0.60$). The items reported as high education needs but low competency by nurses in MFICU were as following: 'postpartum hemorrhage and shock,' 'cardiopulmonary resuscitation (CPR) for neonate,' 'CPR during pregnancy,' 'disseminated intravascular coagulation,' 'sepsis,' and 'mechanical ventilation during pregnancy.' Conclusion: Based on these results, it is proposed that a comprehensive education program for nurses in MFICU should be developed by considering low capabilities among MFICU nurses as a priority factor.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.3
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• pp.60-67
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• 2021

Recently, research attention has been focused on vibration-free vehicles to transport small numbers of expensive electronic products. Vibration-free vehicles can be used to transport expensive test equipment or semiconductors, mainly produced in the domestic IT industry, and can serve as a readily available transportation system for short driving distances due to the increased efficiency on narrow national highways. This study was aimed at developing a Z-Spring to minimize the vibration by installing an air spring instead of the plate spring applied to conventional freight cars and to prevent the damage of the loaded cargo from the shock occurring during movement. The mechanical properties (elastic modulus, tensile strength, and shear strength) of carbon fiber (CF) and glass fiber (GF) prepreg were derived, and ANSYS ACP PrepPost analyses were performed. It was observed that in the case of hybrid composites, the total deformation and equivalent stress are higher than that of CFRP; however, in terms of the unit cost, the hybrid Z-Spring is more inexpensive and durable compared to the GF.

• BMB Reports
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• v.55 no.10
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• pp.512-517
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• 2022

Traumatic brain injury (TBI) is brain damage which is caused by the impact of external mechanical forces. TBI can lead to the temporary or permanent impairment of physical and cognitive abilities, resulting in abnormal behavior. We recently observed that a single session of early exercise in animals with TBI improved their behavioral performance in the absence of other cognitive abnormalities. In the present study, we investigated the therapeutic effects of continuous exercise during the early stages of TBI in rats. We found that continuous low-intensity exercise in early-stage improves the locomotion recovery in the TBI of animal models; however, it does not significantly enhance short-term memory capabilities. Moreover, continuous early exercise not only reduces the protein expression of cerebral damage-related markers, such as Glial Fibrillary Acid Protein (GFAP), Neuron-Specific Enolase (NSE), S100β, Protein Gene Products 9.5 (PGP9.5), and Heat Shock Protein 70 (HSP70), but it also decreases the expression of apoptosis-related protein BAX and cleaved caspase 3. Furthermore, exercise training in animals with TBI decreases the microglia activation and the expression of inflammatory cytokines in the serum, such as CCL20, IL-13, IL-1α, and IL-1β. These findings thus demonstrate that early exercise therapy for TBI may be an effective strategy in improving physiological function, and that serum protein levels are useful biomarkers for the predicition of the effectiveness of early exercise therapy.

• Composites Research
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• v.22 no.2
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• pp.30-36
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• 2009

In this paper, we propose the design method for the composite torque link of a landing gear for a helicopter. The composite torque link has to be light weighted and very stiff to keep the shock absorber in the landing gear of helicopter. The configuration and structural shape has to be designed in consideration of the RTM (Resin Transfer Molding) manufacturing process which is adopted to minimize the manufacturing cost. The mechanical properties are obtained through the coupon tests with the specimens made by the same manufacturing process for the composite structure. The optimal design process was performed through iterative modifications of the models which were verified by stress analysis using FEM. The composite torque link has lug-shaped parts and is very thick, so 3D Layered solid elements of ABAQUS were used to get the stress field including the stress components in thickness direction and non-linear static analysis using contact B.C. of rigid-deform condition was used to get the optimal design.

• Korean Circulation Journal
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• v.53 no.7
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• pp.452-471
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• 2023

The Korean Society of Heart Failure (KSHF) Guidelines provide evidence-based recommendations based on Korean and international data to guide adequate diagnosis and management of heart failure (HF). Since introduction of 2017 edition of the guidelines, management of advanced HF has considerably improved, especially with advances in mechanical circulatory support and devices. The current guidelines addressed these improvements. In addition, we have included recently updated evidence-based recommendations regarding acute HF in these guidelines. In summary, Part IV of the KSHF Guidelines covers the appropriate diagnosis and optimized management of advanced and acute HF.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.2
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• pp.222-229
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• 2024

As the operating condition for the penetrating missile has been more advanced, the survivability of main charge has been strongly required when the warhead impacts the target. Lots of efforts to desensitize explosives such as the development of insensitive molecular explosives or optimizing plastic-bonded explosives(PBX) systems has been made to enhance the survivability of main charge. However, these efforts face their limits as the weapon system require higher performance. Herein, we suggest a new strategy to secure the survivability of main charge. We applied structurally supportable aluminum honeycomb(HC) structure to cast PBX. The aluminum HC structure reinforces the mechanical strength of cast PBX and helps it to withstand external pressure without the reaction like detonation. In this study, impact resistance character, shock sensitivity and internal blast performance of PBXs reinforced with HC structure were investigated according to the application of aluminum HC structure. The newly suggested aluminum HC structure applied to cast PBX was proved to be a promising manufacturing method available for high-tech weapon systems.

• Tuberculosis and Respiratory Diseases
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• v.68 no.5
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• pp.259-266
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• 2010

Background: Pulmonary tuberculosis (TB), requiring the intensive care unit (ICU) care, has been a high-mortality condition until now. In the present study, we aimed to investigate clinical features and parameters associated with TB mortality. Methods: From August 2003 to December 2008, patients with microbiologically or histologically confirmed pulmonary TB then admitted to the ICU, were retrospectively enrolled into the study. Upon enrollment, their medical records were reviewed. Results: Forty three patients (30 males, 13 females) were included and their mean age was 63.8 years (range: 17~87 years). Twelve patients died, an overall in-hospital mortality of 27.8%. The main reason for the ICU care was dyspnea or hypoxemia requiring mechanical ventilation (n=17). Other diagnoses for ICU care were hemoptysis, monitoring after procedures, neurologic dysfunction, shock, and gastrointestinal bleeding. On univariate analysis, the factors affecting the mortality were malnutrition-related parameters including low body mass index, hypoalbuminemia, lymphocytopenia, and hypocholersterolemia, as well as severity-related variables such as high acute physiology and chronic health evaluation (APACHE) score, number of involved lobes, and high C-reactive protein. In addition, respiratory failure requiring mechanical ventilation and acute respiratory distress syndrome contributed to patient fatality. It was shown on multivariate analysis that respiratory failure and hypoalbuminemia were significantly independent variables associated with the mortality. Conclusion: Acute respiratory failure is the most common reason for the ICU care and also the most important factor in predicting poor outcome. In addition, our data suggest that the parameters associated with malnutrition could be possible factors contributing to mortality.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.12
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• pp.106-111
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• 2017

In this study, the stiffness of an LMU (Leg Mating Unit), which is a device required for installing the top side part of an offshore structure, was examined through structural analysis. This unit is mounted on the supporting point of the structure and is used to absorb the shock at installation. It is a cylindrical structure with an empty center. To support the vertical load, elastomeric bearings (EBs) and iron plates are laminated in layers. The stiffness of the EBs is basically influenced by the size of the bearings, but it varies with the number of laminated sheets inside the same sized structure. The relationship between the stiffener and the compressive stiffness is investigated, and its design is suggested. The stiffness of the EBs is analyzed by calculating the reaction force, while controlling the displacement. First, the relationship between the size of the reinforcing plate and the compressive stiffness is considered. Next, the relationship between the number of stacked reinforcing plates and the compression stiffness is considered. Different loads are required for each installed point. The goal is to design the compression stiffness in such a way that the same deformation occurs at each point in the analysis. In this study, ANSYS is used to perform the FE analysis.

• Korean Journal of Optics and Photonics
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• v.22 no.6
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• pp.262-268
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• 2011

MIRIS(Multi-purpose Infra-Red Imaging System) is the main payload of the STSAT-3(Korea Science and Technology Satellite. 3), which is being developed by KASI(Korea Astronomy & Space Institute). EOC(Earth Observation Camera), which is one of two infrared cameras in MIRIS, is the camera for observing infrared rays from the Earth in the range of $3{\sim}5{\mu}m$. The optical system of the EOC is a Cassegrain prescription with aspheric primary and secondary mirrors, and its aperture is 100mm. A ring type flexure supports the EOC primary mirror with pre-loading in order to withstand expected load due to the shock and vibration from the launcher. Here we attempt to use the same mechanism by which a retainer supports the lens. Through opto-mechanical analysis it was confirmed that the EOC primary mirror is effectively supported.