Search results for: Hyun Kyung Sung
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 505

Search results for: Hyun Kyung Sung

145 Antibacterial and Antioxidant Capacity of Fabric Treated with Purple-Fleshed Sweet Potato Extract

Authors: Kyung Hwa Hong, Eunmi Koh

Abstract:

Wool and cotton fabrics are pretreated by a tannic acid aqueous solution to increase their dyeability and then dyed by Purple-Fleshed Sweet Potato (PSP) extract. The dyed fabrics are then investigated by various analysis techniques. The results revealed that wool and cotton fabrics can be dyed bluish red through the pretreatment and dyeing process. Both wool and cotton fabrics only pretreated with tannic acid display decreased L* value but no significant changes in a* and b* values as the concentration of tannic acid increases. And, as expected, the pretreated fabrics are even darker and show a richer purple color after the dyeing process with the PSP extract. With regard to the colorfastness of wool and cotton fabrics dyed by PSP extract in cleaning circumstances, such as dry-cleaning (for wool) and washing (for cotton), the wool and cotton fabrics had a 4.0 and 4.0 grade of colorfastness to dry-cleaning and washing, respectively. However, they both exhibited significantly inferior colorfastness to light (grade of 1.5). Thus, it was found that there is still a need for improvement with regard to color fastness, particularly against light. On the other hand, the wool and cotton fabrics also showed antibacterial and antioxidant characteristics. In addition, both the wool and cotton fabrics showed potential antibacterial ability (>99%) against Staphylococcus aureus; however, they showed somewhat insufficient antibacterial ability (60.8% for wool and 94.8% for cotton) against Klebsiella pneumoniae. Also, their antioxidant abilities increased up to ca. 90% with an increase in the tannic acid concentration (up to 0.5%). However, after the dyeing process, the antibacterial and antioxidant ability tended to decrease. This is assumed to have occurred because functional moieties such as phenolic acids were detached from the pretreated fabrics into the hot water (the dyeing solution) during the dyeing process. Therefore, further study would be necessary to derive the optimum treatment and dyeing conditions so as to maximize the coloring effect and functionalities of the fabrics.

Keywords: antibacterial activity, antioxidant activity, purple-fleshed sweet potato, fabrics

Procedia PDF Downloads 266
144 Effect of Dietary Supplementation of Allium Hookeri Root and Processed Sulfur on the Growth Performance of Guinea Pigs

Authors: Nayeon, Lee, Won-Young, Cho, Hyun Joo, Jang, Chi-Ho, Lee

Abstract:

This study investigated the effects of the dietary supplementation of the Allium hookeri root, and processed sulfur, on the growth performance of guinea pigs. The guinea pigs were fed a control diet (CON), as well as the control diet including 1% freeze-dried Allium hookeri root (AH), or 0.1% processed sulfur (S), or including both the freeze-dried Allium hookeri root and the processed sulfur (AHS). The weight of perirenal adipose tissue (PAT) and the epididymal adipose tissue (EAT) in the AH were significantly lower than CON (p < 0.05). The serum cholesterols levels of the AH and the AHS were significantly lower than the S (p < 0.05). While the total saturated fatty acid content in the serum of the AH and AHS groups showed a tendency to decrease, the total monounsaturated fatty acid increased. The results of this study suggested that dietary consumption of Allium hookeri root may help to decrease fat accumulation, lower serum cholesterol levels, and control serum free fatty acid contents in the guinea pigs.

Keywords: Allium hookeri, dietary supplementation, growth performance, processed sulfur, Guinea pig

Procedia PDF Downloads 237
143 A Comparison between the McGrath Video Laryngoscope and the Macintosh Laryngoscopy in Children with Expected Normal Airway

Authors: Jong Yeop Kim, Ji Eun Kim, Hyun Jeong Kwak, Sook Young Lee

Abstract:

Background: This prospective, randomized, controlled study was performed to evaluate the usefulness of the McGrath VL compared to Macintosh laryngoscopy in children with expected normal airway during endotracheal intubation, by comparing the time to intubation and ease of intubation. Methods: Eighty-four patients, aged 1-10 years undergoing endotracheal intubation for elective surgery were randomly assigned to McGrath group (n = 42) or Macintosh group (n = 42). Anesthesia was induced with propofol 2.5-3.0 mg/kg and sevoflurane 5-8 vol%. Orotracheal intubation was performed 2 minutes after injection of rocuronium 0.6 mg/kg with McGrath VL or Macintosh laryngoscope. The primary outcome was time to intubation. The Cormack and Lehane glottic grade, intubation difficulty score (IDS), and success rate of intubation were assessed. Hemodynamic changes also were recorded. Results: Median time to intubation [interquartile range] was not different between the McGrath group and the Macintosh group (25.0 [22.8-28.3] s vs. 26.0 [24.0-29.0] s, p = 0.301). The incidence of grade I glottic view was significantly higher in theMcGrath group than in the Macintosh group (95% vs. 74%, p = 0.013). Median IDS was lower in the McGrath group than in the Macintosh group (0 [0-0] vs. 0 [0-1], p = 0.018). There were no significant differences in success rate on intubation or hemodynamics between the two groups. Conclusions: McGrath VL provides better laryngeal views and lower IDS, but similar intubation times and success rates compared to the Macintosh laryngoscope in children with the normal airway.

Keywords: intubation, Macintosh laryngoscopy, Mcgrath videolaryngoscopy, pediatrics

Procedia PDF Downloads 205
142 Study on Effect of Reverse Cyclic Loading on Fracture Resistance Curve of Equivalent Stress Gradient (ESG) Specimen

Authors: Jaegu Choi, Jae-Mean Koo, Chang-Sung Seok, Byungwoo Moon

Abstract:

Since massive earthquakes in the world have been reported recently, the safety of nuclear power plants for seismic loading has become a significant issue. Seismic loading is the reverse cyclic loading, consisting of repeated tensile and compression by longitudinal and transverse wave. Up to this time, the study on characteristics of fracture toughness under reverse cyclic loading has been unsatisfactory. Therefore, it is necessary to obtain the fracture toughness under reverse cyclic load for the integrity estimation of nuclear power plants under seismic load. Fracture resistance (J-R) curves, which are used for determination of fracture toughness or integrity estimation in terms of elastic-plastic fracture mechanics, can be derived by the fracture resistance test using single specimen technique. The objective of this paper is to study the effects of reverse cyclic loading on a fracture resistance curve of ESG specimen, having a similar stress gradient compared to the crack surface of the real pipe. For this, we carried out the fracture toughness test under the reverse cyclic loading, while changing incremental plastic displacement. Test results showed that the J-R curves were decreased with a decrease of the incremental plastic displacement.

Keywords: reverse cyclic loading, j-r curve, ESG specimen, incremental plastic displacement

Procedia PDF Downloads 360
141 Effect of Corrosion on the Shear Buckling Strength

Authors: Myoung-Jin Lee, Sung-Jin Lee, Young-Kon Park, Jin-Wook Kim, Bo-Kyoung Kim, Song-Hun Chong, Sun-Ii Kim

Abstract:

The ability to resist the shear strength arises mainly from the web panel of steel girders and as such, the shear buckling strength of these girders has been extensively investigated. For example, Blaser’s reported that when buckling occurs, the tension field has an effect after the buckling strength of the steel is reached. The findings of these studies have been applied by AASHTO, AISC, and to the European Code that provides guidelines for designs aimed at preventing shear buckling. Steel girders are susceptible to corrosion resulting from exposure to natural elements such as rainfall, humidity, and temperature. This corrosion leads to a reduction in the size of the web panel section, thereby resulting in a decrease in the shear strength. The decrease in the panel section has a significant effect on the maintenance section of the bridge. However, in most conventional designs, the influence of corrosion is overlooked during the calculation of the shear buckling strength and hence over-design is common. Therefore, in this study, a steel girder with an A/D of 1:1, as well as a 6-mm-, 16-mm-, and 12-mm-thick web panel, flange, and intermediate reinforcing material, respectively, were used. The total length was set to that (3200 mm) of the default model. The effect of corrosion shear buckling was investigated by determining the volume amount of corrosion, shape of the erosion patterns, and the angular change in the tensile field of the shear buckling strength. This study provides the basic data that will enable designs that incorporate values closer (than those used in most conventional designs) to the actual shear buckling strength.

Keywords: corrosion, shear buckling strength, steel girder, shear strength

Procedia PDF Downloads 342
140 Numerical Simulation of Fluid-Structure Interaction on Wedge Slamming Impact by Using Particle Method

Authors: Sung-Chul Hwang, Di Ren, Sang-Moon Yoon, Jong-Chun Park, Abbas Khayyer, Hitoshi Gotoh

Abstract:

The slamming impact problem has a very important engineering background. For seaplane landing, recycling for the satellite re-entry capsule, and the impact load of the bow in the adverse sea conditions, the slamming problem always plays the important role. Due to its strong nonlinear effect, however, it seems to be not easy to obtain the accurate simulation results. Combined with the strong interaction between the fluid field and the elastic structure, the difficulty for the simulation leads to a new level for challenging. This paper presents a fully Lagrangian coupled solver for simulations of fluid-structure interactions, which is based on the Moving Particle Semi-implicit (MPS) method to solve the governing equations corresponding to incompressible flows as well as elastic structures. The developed solver is verified by reproducing the high velocity impact loads of deformable thin wedges with two different materials such as aluminum and steel on water entry. The present simulation results are compared with analytical solution derived using the hydrodynamic Wagner model and linear theory by Wan.

Keywords: fluid-structure interaction, moving particle semi-implicit (MPS) method, elastic structure, incompressible flow, wedge slamming impact

Procedia PDF Downloads 569
139 Cotton Treated with Spent Coffee Extract for Realizing Functional Textiles

Authors: Kyung Hwa Hong

Abstract:

The objective of this study was to evaluate the ability of spent coffee extract to enhance the antioxidant and antimicrobial properties of cotton fabrics. The emergence and spread of infectious diseases has raised a global interest in the antimicrobial substances. The safety of chemical agents, such as antimicrobials and dyes, which may irritate the skin, cause cellular and organ damage, and have adverse environmental impacts during their manufacturing, in relation to the human body has not been established. Nevertheless, there is a growing interest in natural antimicrobials that kill microorganisms or stop their growth without dangerous effects on human health. Spent coffee is the by-product of coffee brewing and amounted to 96,000 tons worldwide in 2015. Coffee components such as caffeine, melanoidins, and chlorogenic acid have been reported to possess multifunctional properties, including antimicrobial, antioxidant, and anti-inflammatory activities. Therefore, the current study examined the possibility of applying spent coffee in functional textile finishing. Spent coffee was extracted with 60% methanol solution, and the major components of the extract were quantified. In addition, cotton fabrics treated with spent coffee extract through a pad-dry-cure process were investigated for antioxidant and antimicrobial activities. The cotton fabrics finished with the spent coffee extract showed an increase in yellowness, which is an unfavorable outcome from the fabric finishing process. However, the cotton fabrics finished with the spent coffee extract exhibited considerable antioxidant activity. In particular, the antioxidant ability significantly increased with increasing concentrations of the spent coffee extract. The finished cotton fabrics showed antimicrobial ability against S. aureus but relatively low antimicrobial ability against K. pneumoniae. Therefore, further investigations are needed to determine the appropriate concentration of spent coffee extract to inhibit the growth of various pathogenic bacteria.

Keywords: spent coffee grounds, cotton, natural finishing agent, antioxidant activity, antimicrobial activity

Procedia PDF Downloads 131
138 A Promising Thrombolytic and Anticoagulant Serine Protease Purified from Lug Worms Inhabiting Tidal Flats

Authors: Hye Jin Kim, Hwa Sung Shin

Abstract:

Ischemic stroke means the caused brain damage due to neurological defects, occurring occlusion of cerebral vascular resulting in thrombus or embolism. t-PA (tissue Plasminogen Activator) is the only thrombolytic agent passed the FDA (Food and Drug Administration). However, t-PA directly dissolves the thrombus (direct activity) through fibrinolysis, showing side effects such as re-occlusion. In this study, we evaluated the thrombolytic activities of the serine protease extracted from lugworms inhabiting tidal flats. The new serine protease identified as 38 kDa by SDS-PAGE was not toxic to brain endothelial cells line (hCMEC/D3). Also, the plasmin synthesis inhibition activity (indirect activity) of the new serine protease was confirmed through fibrin zymography assay and fibrin plate assay. It was higher than direct activity as compared to u-PA (urokinase Plasminogen Activator). The activities were found to be maintained at a wide range of temperature (4-70 ℃) and pH 7-10 compared to previous thrombolytic agents from the azocasein assay. In addition, the new serine protease has shown anticoagulant activity from fibrinogenolytic activity assay. In conclusion, the serine protease in lug worms inhabiting the tidal flats could be considered a promising thrombolytic candidate for the treatment of ischemic stroke.

Keywords: alkaline serine protease, bifunctional thrombolytic activity, fibrinolytic activity, ischemic stroke, lug worms

Procedia PDF Downloads 297
137 High Temperature Properties of Diffusion Brazed Joints of in 939 Ni-Base Superalloy

Authors: Hyun KI Kang, Hi Won Jeong

Abstract:

The gas turbine operates for a long period of time under harsh, cyclic conditions of high temperature and pressure, where high turbine inlet temperature (TIT) can range from 1273 to 1873K. Therefore, Ni-base superalloys such as IN738, IN939, Rene 45, Rene 71, Rene 80, Mar M 247, CM 247, and CMSX-4 with excellent mechanical properties and resistance to creep, corrosion and oxidation at high temperatures are indeed used. Among the alloying additions for these alloys, aluminum (Al) and titanium (Ti) form gamma prime and enhance the high-temperature properties. However, when crack-damaged high-temperature turbine components such as blade and vane are repaired by fusion welding, they cause cracks. For example, when arc welding is applied to certain superalloys that contain Al and Ti with more than 3 wt.% and T3.5 wt%, respectively, such as IN738, IN939, Rene 80, Mar M 247, and CM 247, aging cracks occur. Therefore, repair technologies using diffusion brazing, which has less heat input into the base material, are being developed. Analysis of microstructural evolution of the brazed joints with a base metal of IN 939 Ni-base superalloy using brazing different filler metals was also carried out using X-ray diffraction, OEM, SEM-EDS, and EPMA. Stress rupture and high-temperature tensile strength properties were also measured to analyze the effects of different brazing heat cycles. The boron amount in the diffusion-affected zone (DAZ) was decreased towards the base metal and the formation of borides at grain boundaries was detected through EPMA.

Keywords: gas turbine, diffusion brazing, superalloy, gas turbine repair

Procedia PDF Downloads 13
136 An Experimental Study on the Optimum Installation of Fire Detector for Early Stage Fire Detecting in Rack-Type Warehouses

Authors: Ki Ok Choi, Sung Ho Hong, Dong Suck Kim, Don Mook Choi

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Rack type warehouses are different from general buildings in the kinds, amount, and arrangement of stored goods, so the fire risk of rack type warehouses is different from those buildings. The fire pattern of rack type warehouses is different in combustion characteristic and storing condition of stored goods. The initial fire burning rate is different in the surface condition of materials, but the running time of fire is closely related with the kinds of stored materials and stored conditions. The stored goods of the warehouse are consisted of diverse combustibles, combustible liquid, and so on. Fire detection time may be delayed because the residents are less than office and commercial buildings. If fire detectors installed in rack type warehouses are inadaptable, the fire of the warehouse may be the great fire because of delaying of fire detection. In this paper, we studied what kinds of fire detectors are optimized in early detecting of rack type warehouse fire by real-scale fire tests. The fire detectors used in the tests are rate of rise type, fixed type, photo electric type, and aspirating type detectors. We considered optimum fire detecting method in rack type warehouses suggested by the response characteristic and comparative analysis of the fire detectors.

Keywords: fire detector, rack, response characteristic, warehouse

Procedia PDF Downloads 713
135 Transient Simulation Using SPACE for ATLAS Facility to Investigate the Effect of Heat Loss on Major Parameters

Authors: Suhib A. Abu-Seini, Kyung-Doo Kim

Abstract:

A heat loss model for ATLAS facility was introduced using SPACE code predefined correlations and various dialing factors. As all previous simulations were carried out using a heat loss free input; the facility was considered to be completely insulated and the core power was reduced by the experimentally measured values of heat loss to compensate to the account for the loss of heat, this study will consider heat loss throughout the simulation. The new heat loss model will be affecting SPACE code simulation as heat being leaked out of the system throughout a transient will alter many parameters corresponding to temperature and temperature difference. For that, a Station Blackout followed by a multiple Steam Generator Tube Rupture accident will be simulated using both the insulated system approach and the newly introduced heat loss input of the steady state. Major parameters such as system temperatures, pressure values, and flow rates to be put into comparison and various analysis will be suggested upon it as the experimental values will not be the reference to validate the expected outcome. This study will not only show the significance of heat loss consideration in the processes of prevention and mitigation of various incidents, design basis and beyond accidents as it will give a detailed behavior of ATLAS facility during both processes of steady state and major transient, but will also present a verification of how credible the data acquired of ATLAS are; since heat loss values for steady state were already mismatched between SPACE simulation results and ATLAS data acquiring system. Acknowledgement- This work was supported by the Korean institute of Energy Technology Evaluation and Planning (KETEP) and the Ministry of Trade, Industry & Energy (MOTIE) of the Republic of Korea.

Keywords: ATLAS, heat loss, simulation, SPACE, station blackout, steam generator tube rupture, verification

Procedia PDF Downloads 202
134 Multi-Factor Optimization Method through Machine Learning in Building Envelope Design: Focusing on Perforated Metal Façade

Authors: Jinwooung Kim, Jae-Hwan Jung, Seong-Jun Kim, Sung-Ah Kim

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Because the building envelope has a significant impact on the operation and maintenance stage of the building, designing the facade considering the performance can improve the performance of the building and lower the maintenance cost of the building. In general, however, optimizing two or more performance factors confronts the limits of time and computational tools. The optimization phase typically repeats infinitely until a series of processes that generate alternatives and analyze the generated alternatives achieve the desired performance. In particular, as complex geometry or precision increases, computational resources and time are prohibitive to find the required performance, so an optimization methodology is needed to deal with this. Instead of directly analyzing all the alternatives in the optimization process, applying experimental techniques (heuristic method) learned through experimentation and experience can reduce resource waste. This study proposes and verifies a method to optimize the double envelope of a building composed of a perforated panel using machine learning to the design geometry and quantitative performance. The proposed method is to achieve the required performance with fewer resources by supplementing the existing method which cannot calculate the complex shape of the perforated panel.

Keywords: building envelope, machine learning, perforated metal, multi-factor optimization, façade

Procedia PDF Downloads 193
133 Safety and Efficacy of Recombinant Clostridium botulinum Types B Vaccine Candidate

Authors: Mi-Hye Hwang, Young Min Son, Kichan Lee, Bang-Hun Hyun, Byeong Yeal Jung

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Botulism is a paralytic disease of human beings and animals caused by neurotoxin produced by Clostridium botulinum. The neurotoxins are genetically distinguished into 8 types, A to H. Ingestion of performed toxin, usually types B, C, and D, have been shown to produce diseases in most cases of cattle botulism. Vaccination is the best measure to prevent cattle botulism. However, the commercially available toxoid-based vaccines are difficult and hazardous to produce. We produced recombinant protein using gene of heavy chain domain of botulinum toxin B of which binds to cellular receptor of neuron cells and used as immunogen. In this study, we evaluated the safety and efficacy of botulism vaccine composed of recombinant types B. Safety test was done by National Regulation for Veterinary Biologicals. For efficacy test, female ICR mice (5 weeks old) were subcutaneously injected, intraperitoneally challenged, and examined the survival rates compared with vaccination and non-vaccination group. Mouse survival rate of recombinant types B vaccine was above 80%, while one of non-vaccination group was 0%. A vaccine composed of recombinant types B was safe and efficacious in mouse. Our results suggest that recombinant heavy chain receptor binding domain can be used as an effective vaccine candidate for type B botulism.

Keywords: botulism, livestock, vaccine, recombinant protein, toxin

Procedia PDF Downloads 201
132 Physical Health, Depression and Related Factors for Elementary School Students in Seoul, South Korea

Authors: Kyung-Sook Bang

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Background: The health status of school-age children has a great influence on their growth and life-long health. The purposes of this study were to identify physical and mental health status of late school-age children in Seoul, South Korea and to investigate the related factors for their health. Methods: After gaining the approval from Institutional Review Board (IRB), a cross-sectional study was conducted with elementary students in grade 4 or 5. Questionnaires were distributed to eight elementary schools located different regions of Seoul in November, 2016, and 302 participants were finally included. From all participants, informed consents from the parents, and assents from children were received. Children's socioeconomic status, family functioning, peer relations, physical health symptoms, and depression were measured with self-reported questionnaires. Data were analyzed with descriptive statistics, t-test, Pearson’s correlations, and multiple regression. Results: Children's physical health symptoms and depression were not significantly different, and only their peer relations were significantly different according to their socioeconomic status (t=-3.93, p<.001). Depression showed significant positive correlation with physical health symptoms (r=.720, p<.001) and negative correlations with family functioning (r=-.428, p<.001) and peer relations (r=-.775, p<.001). The multiple regression model, which explained 73.5% of variance, showed peer relations (r2 =.604), physical health symptoms (r2 change=.125), and family functioning (r2 change=.005) as significant predictors for depression. Only the peer relations was significant predictor for their physical health symptoms and explained 50.6% of it. Conclusions: The peer relations was the most important factor in their physical and mental health at this age, and it can be affected by their socioeconomic status. Nursing interventions for promoting social relations and family functioning are required to improve children’s physical and mental health, especially for vulnerable population.

Keywords: child, depression, health, peer relation

Procedia PDF Downloads 200
131 A Cellular-Based Structural Health Monitoring Device (HMD) Based on Cost-Effective 1-Axis Accelerometers

Authors: Chih-Hsing Lin, Wen-Ching Chen, Chih-Ting Kuo, Gang-Neng Sung, Chih-Chyau Yang, Chien-Ming Wu, Chun-Ming Huang

Abstract:

This paper proposes a cellular-based structure health monitoring device (HMD) for temporary bridge monitoring without the requirement of power line and internet service. The proposed HMD includes sensor node, power module, cellular gateway, and rechargeable batteries. The purpose of HMD focuses on short-term collection of civil infrastructure information. It achieves the features of low cost by using three 1-axis accelerometers with data synchronization problem being solved. Furthermore, instead of using data acquisition system (DAQ) sensed data is transmitted to Host through cellular gateway. Compared with 3-axis accelerometer, our proposed 1-axis accelerometers based device achieves 50.5% cost saving with high sensitivity 2000mv/g. In addition to fit different monitoring environments, the proposed system can be easily replaced and/or extended with different PCB boards, such as communication interfaces and sensors, to adapt to various applications. Therefore, with using the proposed device, the real-time diagnosis system for civil infrastructure damage monitoring can be conducted effectively.

Keywords: cellular-based structural health monitoring, cost-effective 1-axis accelerometers, short-term monitoring, structural engineering

Procedia PDF Downloads 488
130 A Study on Prediction Model for Thermally Grown Oxide Layer in Thermal Barrier Coating

Authors: Yongseok Kim, Jeong-Min Lee, Hyunwoo Song, Junghan Yun, Jungin Byun, Jae-Mean Koo, Chang-Sung Seok

Abstract:

Thermal barrier coating(TBC) is applied for gas turbine components to protect the components from extremely high temperature condition. Since metallic substrate cannot endure such severe condition of gas turbines, delamination of TBC can cause failure of the system. Thus, delamination life of TBC is one of the most important issues for designing the components operating at high temperature condition. Thermal stress caused by thermally grown oxide(TGO) layer is known as one of the major failure mechanisms of TBC. Thermal stress by TGO mainly occurs at the interface between TGO layer and ceramic top coat layer, and it is strongly influenced by the thickness and shape of TGO layer. In this study, Isothermal oxidation is conducted on coin-type TBC specimens prepared by APS(air plasma spray) method. After the isothermal oxidation at various temperature and time condition, the thickness and shape(rumpling shape) of the TGO is investigated, and the test data is processed by numerical analysis. Finally, the test data is arranged into a mathematical prediction model with two variables(temperature and exposure time) which can predict the thickness and rumpling shape of TGO.

Keywords: thermal barrier coating, thermally grown oxide, thermal stress, isothermal oxidation, numerical analysis

Procedia PDF Downloads 316
129 Radial Distortion Correction Based on the Concept of Verifying the Planarity of a Specimen

Authors: Shih-Heng Tung, Ming-Hsiang Shih, Wen-Pei Sung

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Because of the rapid development of digital camera and computer, digital image correlation method has drawn lots of attention recently and has been applied to a variety of fields. However, the image distortion is inevitable when the image is captured through a lens. This image distortion problem can result in an innegligible error while using digital image correlation method. There are already many different ways to correct the image distortion, and most of them require specific image patterns or precise control points. A new distortion correction method is proposed in this study. The proposed method is based on the fact that a flat surface should keep flat when it is measured using three-dimensional (3D) digital image measurement technique. Lens distortion can be divided into radial distortion, decentering distortion and thin prism distortion. Because radial distortion has a more noticeable influence than the other types of distortions, this method deals only with radial distortion. The simplified 3D digital image measurement technique is adopted to measure the surface coordinates of a flat specimen. Then the gradient method is applied to find the best correction parameters. A few experiments are carried out in this study to verify the correctness of this method. The results show that this method can achieve a good accuracy and it is suitable for both large and small distortion conditions. The most important advantage is that it requires neither mark with specific pattern nor precise control points.

Keywords: 3D DIC, radial distortion, distortion correction, planarity

Procedia PDF Downloads 524
128 Discovery of New Inhibitors for Colorectal Cancer Treatment

Authors: Kai-Cheng Hsu, Tzu-Ying Sung, Jinn-Moon Yang

Abstract:

Colorectal cancer (CRC) is one of the main causes of cancer death in the world. Although several drugs have been developed to treat colorectal cancer, such as Regorafenib and 5-FU, their efficacy is often limited by the development of drug resistance. Therefore, development of new drugs with new scaffolds is necessary to treat CRC. Here, we used site-moiety maps to identify inhibitors against PIM1, LIMK1, SRC, and mTOR, which are often overexpressed in CRC. A site-moiety map represents physicochemical properties and moiety preferences of a binding site through anchors. An anchor contains three elements: (1) conserved interacting residues of a binding pocket; (2) moiety preference of the binding pocket; and (3) the type (e.g., hydrogen-bonding or van der Waals interactions) of interaction between the moieties and the binding pocket. Then, we performed a structure-based virtual screening of ~260,000 compounds and selected compound candidates with high site-moiety map scores for bioassays. Among these candidates, compound 1 and compound 2 inhibited the growth of CRC cells with IC50 values of <10 μM. The experimental result of enzyme-based assays indicated that compound 1 is a dual inhibitor against PIM1 (IC50 6 μM) and LIMK1(IC50 11 μM). Compound 2 was predicted as a SRC inhibitor and will be further validated. The compounds inhibited different protein targets compared to the current drugs. We believe that the compounds provide a starting point to design new drugs for CRC treatment.

Keywords: colorectal cancer, drug discovery, site-moiety map, virtual screening, PIM1, LIMK1

Procedia PDF Downloads 215
127 Drag Reduction of Base Bleed at Various Flight Conditions

Authors: Man Chul Jeong, Hyoung Jin Lee, Sang Yoon Lee, Ji Hyun Park, Min Wook Chang, In-Seuck Jeung

Abstract:

This study focus on the drag reduction effect of the base bleed at supersonic flow. Base bleed is the method which bleeds the gas on the tail of the flight vehicle and reduces the base drag, which occupies over 50% of the total drag in any flight speed. Thus base bleed can reduce the total drag significantly, and enhance the total flight range. Drag reduction ratio of the base bleed is strongly related to the mass flow rate of the bleeding gas. Thus selecting appropriate mass flow rate is important. However, since the flight vehicle has various flight speed, same mass flow rate of the base bleed can have different drag reduction effect during the flight. Thus, this study investigates the effect of the drag reduction depending on the flight speed by numerical analysis using STAR-CCM+. The analysis model is 155mm diameter projectile with boat-tailed shape base. Angle of the boat-tail is chosen previously for minimum drag coefficient. Numerical analysis is conducted for Mach 2 and Mach 3, with various mass flow rate, or the injection parameter I, of the bleeding gas and the temperature of the bleeding gas, is fixed to 300K. The results showed that I=0.025 has the minimum drag at Mach 2, and I=0.014 has the minimum drag at Mach 3. Thus as the Mach number is higher, the lower mass flow rate of the base bleed has more effect on drag reduction.

Keywords: base bleed, supersonic, drag reduction, recirculation

Procedia PDF Downloads 389
126 Hypothesis on Annual Sea Level Variation and Increased Volume Transport in Korea Strait

Authors: Young-Taeg Kim, Gwang Ho Seo, Hyungju Oh, Ho Kyung Ha, Kuk Jin Kim

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Kim et al., hypothesized an increase in volume transport in the Korea Strait based on the concurrent increase in water temperature and mean sea level observed by the Korea Hydrographic and Oceanographic Agency (KHOA) in the vicinity of the Korea Strait from 2000 to 2009. Since then, to our best knowledge, no definitive studies have been reported on the increase in volume transport through the Korea Strait, but the observed water temperature (2000-2021) and sea level (1989-2021) in the Korea Strait and East Sea have been found to be increasing. In particular, the rapid increase rate in the mean sea level rise (2.55~3.53 mm/y) in these areas cannot be explained by only steric effect due to the increased water temperature. It is more reasonable interpretation that the sea level rise is due to an increase in the volume transport of warm and salty currents. If the increase in the volume transport is explained by the geostrophic equation without considering the sea level rise in the Korea Strait, the current velocity should increase. However, up to now, there are no reports of an increase in current velocity from direct observations using ADCP (e.g., observations of Camellia) or from various numerical models. Therefore, the increase in volume transport cannot be explained by the geostrophic equation. Another possible explanation for the increase in the volume transport is the effect of wind. Although Korea is dominated by monsoon, it is affected by winds according to El Niño and La Niña, which have a cycle of about 3 to 4 years. During El Niño (La Niña), northerly winds (southerly winds) prevail in Korea. Consequently, it is inferred that the transported volume in the Korea Strait slowly increases interannually. However, in this study, it was difficult to find a clear correlation between annually-averaged mean sea level and El Niño (or La Niña) during 1989-2021. This is probably due to the interactions of the PDO (Pacific Decadal Oscillation) and AO (Arctic Oscillation) along with the ENSO (El niño-Southern Oscillation). However, it is clear that the interannual variability of winds is affecting the volume transport in the Korean Strait. On the other hand, the effect of global sea level rise on the volume transport in the Korea Strait is small compared to the interannual variability of the volume transport, but it seems to play a constant role.

Keywords: mean sea level, volume transport, El nino, La nina

Procedia PDF Downloads 37
125 A Systematic Review of the Methodological and Reporting Quality of Case Series in Surgery

Authors: Riaz A. Agha, Alexander J. Fowler, Seon-Young Lee, Buket Gundogan, Katharine Whitehurst, Harkiran K. Sagoo, Kyung Jin Lee Jeong, Douglas G. Altman, Dennis P. Orgill

Abstract:

Introduction: Case Series are an important and common study type. Currently, no guideline exists for reporting case series and there is evidence of key data being missed from such reports. We propose to develop a reporting guideline for case series using a methodologically robust technique. The first step in this process is a systematic review of literature relevant to the reporting deficiencies of case series. Methods: A systematic review of methodological and reporting quality in surgical case series was performed. The electronic search strategy was developed by an information specialist and included MEDLINE, EMBASE, Cochrane Methods Register, Science Citation index and Conference Proceedings Citation index, from the start of indexing until 5th November 2014. Independent screening, eligibility assessments and data extraction was performed. Included articles were analyzed for five areas of deficiency: failure to use standardized definitions missing or selective data transparency or incomplete reporting whether alternate study designs were considered. Results: The database searching identified 2,205 records. Through the process of screening and eligibility assessments, 92 articles met inclusion criteria. Frequency of methodological and reporting issues identified was a failure to use standardized definitions (57%), missing or selective data (66%), transparency, or incomplete reporting (70%), whether alternate study designs were considered (11%) and other issues (52%). Conclusion: The methodological and reporting quality of surgical case series needs improvement. Our data shows that clear evidence-based guidelines for the conduct and reporting of a case series may be useful to those planning or conducting them.

Keywords: case series, reporting quality, surgery, systematic review

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124 Depressant Effects of 2-PMPA through Reduction of p-CREB (Ser133) and mGluR5 Level in Prefrontal Cortex of C57BL/6 Mice

Authors: Sang-Sun Yoon, Yea-Hyun Leem, Sangmee Ahn Jo

Abstract:

The N-acetylated-alpha-linked-acidic (NAAG) peptidase inhibitor 2-phosphonomethyl pentanedioic acid (2-PMPA) has demonstrated to be neuroprotective against glutamate-mediated neuron degeneration and neurological disorders such as ischemia. Several studies have demonstrated impaired psychiatric function by altered glutamate carboxypeptidase II expression, although 2-PMPA has not yet been studied. Thus, we investigated effect of 2-PMPA on depressive-like phenotype using C57BL/6 mice. Treatment of 2-PMPA (10 mg/kg for 6 days/daily, ip injection) on C57BL/6 naïve mice showed depressive-like symptoms such as decreased social preference, but did not affect the immobility measured by tail suspension test. Reduction of phosphorylated cAMP-responsive element binding (p-CREB) known as a representative marker of depressive-like behavior was observed in layer 1 and piriform cortex subregions of the prefrontal cortex of 2-PMPA-treated mice. The immunoreactivity of metabotropic glutamate receptors 5 (mGluR5) that mediate phosphorylation of CREB was also decreased in layer 1 and piriform cortex subregions of the prefrontal cortex of 2-PMPA injected mice. Thus, our results suggest that dysregulation of the GCPII or NAAG by 2-PMPA treatment is likely to be associated with pathogenesis of depression and further studies are needed to understand whether the reduced NAAG level or enhanced glutamate level in the brain is involved in this response.

Keywords: depression, GCPII, 2-PMPA, p-CREB, mGluR5

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123 Fuzzy Inference-Assisted Saliency-Aware Convolution Neural Networks for Multi-View Summarization

Authors: Tanveer Hussain, Khan Muhammad, Amin Ullah, Mi Young Lee, Sung Wook Baik

Abstract:

The Big Data generated from distributed vision sensors installed on large scale in smart cities create hurdles in its efficient and beneficial exploration for browsing, retrieval, and indexing. This paper presents a three-folded framework for effective video summarization of such data and provide a compact and representative format of Big Video Data. In the first fold, the paper acquires input video data from the installed cameras and collect clues such as type and count of objects and clarity of the view from a chunk of pre-defined number of frames of each view. The decision of representative view selection for a particular interval is based on fuzzy inference system, acquiring a precise and human resembling decision, reinforced by the known clues as a part of the second fold. In the third fold, the paper forwards the selected view frames to the summary generation mechanism that is supported by a saliency-aware convolution neural network (CNN) model. The new trend of fuzzy rules for view selection followed by CNN architecture for saliency computation makes the multi-view video summarization (MVS) framework a suitable candidate for real-world practice in smart cities.

Keywords: big video data analysis, fuzzy logic, multi-view video summarization, saliency detection

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122 Efficacy and Safety of Uventa Metallic Stent for Malignant and Benign Ureteral Obstruction

Authors: Deok Hyun Han

Abstract:

Objective: To explore outcomes of UventaTM metallic ureteral stent between malignant and benign ureteral obstruction. Methods: We reviewed the medical records of 90 consecutive patients who underwent Uventa stent placement for benign or malignant ureteral obstruction from December 2009 to June 2013. We evaluated the clinical outcomes, complications, and reasons and results for unexpected stent removals. Results: The median follow-up was 10.7 (0.9 – 41) months. From a total of 125 ureter units, there were 24 units with benign obstructions and 101 units with malignant obstructions. Initial technical successes were achieved in all patients. The overall success rate was 70.8% with benign obstructions and 84.2% with malignant obstructions. The major reasons for treatment failure were stent migration (12.5%) in benign and tumor progression (11.9%) in malignant obstructions. The overall complication rate was similar between benign and malignant obstructions (58.3% and 42.6%), but severe complications, which are Clavien grade 3 or more, occurred in 41.7% of benign and 6.9% of malignant obstructions. The most common complications were stent migration (25.0%) in benign obstructions and persistent pain (14.9%) in malignant obstructions. The stent removal was done in 16 units; nine units that were removed by endoscopy and seven units were by open surgery. Conclusions: In malignant ureteral obstructions, the Uventa stent showed favorable outcomes with high success rate and acceptable complication rate. However, in benign ureteral obstructions, overall success rate and complication rate were less favorable. Malignant ureteral obstruction seems to be appropriate indication of Uventa stent placement. However, in chronic diffuse benign ureteral obstructions the decision of placement of Uventa stent has to be careful.

Keywords: cause, complication, ureteral obstruction, metal stent

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121 A Study on Effect of Dynamic Loading Speed on the Fracture Toughness of Equivalent Stress Gradient (ESG) Specimen

Authors: Moon Byung Woo, Seok Chang-Sung, Koo Jae-Mean, Kim Sang-Young, Choi Jae Gu, Huh Nam-Su

Abstract:

Recently, the occurrence of the earthquake has increased sharply and many of the casualties have occurred worldwide, due to the influence of earthquakes. Especially, the Fukushima nuclear power plant accident which was caused by the earthquake in 2011 has significantly increased the fear of people and the demand for the safety of the nuclear power plant. Thus, in order to prevent the earthquake accident at nuclear power plant, it is important to evaluate the fracture toughness considering the seismic loading rate. To obtain fracture toughness for the safety evaluation of nuclear power plant, it is desirable to perform experiments with a real scale pipe which is expensive and hard to perform. Therefore, many researchers have proposed various test specimens to replicate the fracture toughness of a real scale pipe. Since such specimens have several problems, the equivalent stress gradient (ESG) specimen has been recently suggested. In this study, in order to consider the effects of the dynamic loading speed on fracture toughness, the experiment was conducted by applying five different kinds of test speeds using an ESG specimen. In addition, after we performed the fracture toughness test under dynamic loading with different speeds using an ESG specimen and a standard specimen, we compared them with the test results under static loading.

Keywords: dynamic loading speed, fracture toughness, load-ratio-method, equivalent stress gradient (ESG) specimen

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120 Hydrodynamics and Heat Transfer Characteristics of a Solar Thermochemical Fluidized Bed Reactor

Authors: Selvan Bellan, Koji Matsubara, Nobuyuki Gokon, Tatsuya Kodama, Hyun Seok-Cho

Abstract:

In concentrated solar thermal industry, fluidized-bed technology has been used to produce hydrogen by thermochemical two step water splitting cycles, and synthetic gas by gasification of coal coke. Recently, couple of fluidized bed reactors have been developed and tested at Niigata University, Japan, for two-step thermochemical water splitting cycles and coal coke gasification using Xe light, solar simulator. The hydrodynamic behavior of the gas-solid flow plays a vital role in the aforementioned fluidized bed reactors. Thus, in order to study the dynamics of dense gas-solid flow, a CFD-DEM model has been developed; in which the contact forces between the particles have been calculated by the spring-dashpot model, based on the soft-sphere method. Heat transfer and hydrodynamics of a solar thermochemical fluidized bed reactor filled with ceria particles have been studied numerically and experimentally for beam-down solar concentrating system. An experimental visualization of particles circulation pattern and mixing of two-tower fluidized bed system has been presented. Simulation results have been compared with experimental data to validate the CFD-DEM model. Results indicate that the model can predict the particle-fluid flow of the two-tower fluidized bed reactor. Using this model, the key operating parameters can be optimized.

Keywords: solar reactor, CFD-DEM modeling, fluidized bed, beam-down solar concentrating system

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119 Bifid Ureters: Arising Directly from the Separate Calyces and Renal Pelvis of the Kidney: A Case Report

Authors: Yuri Seu, Hyun Jin Park, Jin Seo Park, Yong-Suk Moon, HongtaeKim, Mi-Sun Hur

Abstract:

The present case report describes bifid ureters arising directly from the separate calyces and renal pelvis of the kidney. It was a single common ureter leading away from the bladder, which was separated into incompletely duplicated ureters near the level of the anterior superior iliac supine. These two branches then entered the left kidney through their own courses. Each ureter traveled anterior and posterior to the renal vein, respectively. These two ureters formed a Y-shaped pattern. One ureter coursed anterior to the renal vein with shorter length, and it terminated at the renal pelvis that was divided into major calices in approximately lower two thirds of the kidney. The other ureter coursed posterior to the renal vein with longer length, terminating at approximately the upper third of the kidney. The renal calices in the upper third of the kidney were directly connected to the posterior ureter, whereas the other major calices in the lower two thirds of the kidney formed the renal pelvis connecting to the anterior ureter. Thus, convergence of the major calices was separated according to the terminations of two ureters. These anomalous ureters were traced to the calices of the kidney, thereby providing a reference of a rare variation of the ureter. The bifid ureters arising from the separate calyces and renal pelvis should be considered by radiologists when evaluating images and diagnosing possible complications of these anomalies.

Keywords: bifid ureters, kidney, major calices, renal pelvis

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118 The Design Optimization for Sound Absorption Material of Multi-Layer Structure

Authors: Un-Hwan Park, Jun-Hyeok Heo, In-Sung Lee, Tae-Hyeon Oh, Dae-Kyu Park

Abstract:

Sound absorbing material is used as automotive interior material. Sound absorption coefficient should be predicted to design it. But it is difficult to predict sound absorbing coefficient because it is comprised of several material layers. So, its targets are achieved through many experimental tunings. It causes a lot of cost and time. In this paper, we propose the process to estimate the sound absorption coefficient with multi-layer structure. In order to estimate the coefficient, physical properties of each material are used. These properties also use predicted values by Foam-X software using the sound absorption coefficient data measured by impedance tube. Since there are many physical properties and the measurement equipment is expensive, the values predicted by software are used. Through the measurement of the sound absorption coefficient of each material, its physical properties are calculated inversely. The properties of each material are used to calculate the sound absorption coefficient of the multi-layer material. Since the absorption coefficient of multi-layer can be calculated, optimization design is possible through simulation. Then, we will compare and analyze the calculated sound absorption coefficient with the data measured by scaled reverberation chamber and impedance tubes for a prototype. If this method is used when developing automotive interior materials with multi-layer structure, the development effort can be reduced because it can be optimized by simulation. So, cost and time can be saved.

Keywords: sound absorption material, sound impedance tube, sound absorption coefficient, optimization design

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117 Evaluation of the Safety and Performance of Blood Culture Practices Using BD Safety-Lokᵀᴹ Blood Collection Sets in the Emergency Room

Authors: Jeonghyun Chang, Taegeun Lee, Heungsup Sung, Yoon-Seon Lee, Youn-Jung Kim, Mi-Na Kim

Abstract:

Background: Safety device has been applied to improve safety and performance of blood culture practice. BD vacutainer® Safety-Lokᵀᴹ blood collection sets with pre-attached holder (Safety-Lok) (BD, USA) was evaluated in the emergency room (ER) of a tertiary care hospital. Methods: From April to June 2017, interns and nurses in ER were surveyed for blood culture practices with a questionnaire before and after 2 or 3 weeks of experience of Safety-Lok. All of them participated in exercise workshop for 1 hour combined with video education prior to the initial survey. The blood volume, positive and contamination rates of Safety-Lok-drawn (SD) blood cultures were compared to those of overall blood cultures. Results: Eighteen interns and 30 nurses were enrolled. As a result of the initial survey, interns had higher rates of needlestick incidence (27.8%), carriage of the blood-filled syringe with needle (88.9%) and lower rates of vacutainer use (38.9%) than nurses (13.3%, 53.3%, and 60.0%). Interns preferred to use safety devices (88.9%) rather than nurses (40.0%). The number of overall blood cultures and SD blood cultures was 9,053 and 555, respectively. While the overall blood volume of aerobic bottles was 2.6±2.1 mL, those of SD blood cultures were 5.0±3.0 mL in aerobic bottles and 6.0±3.0 mL in anaerobic bottles. Positive and contamination rates were 6.5% and 0.72% with SD blood cultures and 6.2% and 0.3% with overall blood cultures. Conclusions: The introduction of the safety device would encourage healthcare workers to collect adequate blood volume as well as lead to safer practices in the ER.

Keywords: blood culture, needlestick, safety device, volume

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116 Feasibility Study on a Conductive-Type Cooling System for an Axial Flux Permanent Magnet Generator

Authors: Yang-Gyun Kim, Eun-Taek Woo, Myeong-Gon Lee, Yun-Hyun Cho, Seung-Ho Han

Abstract:

For the sustainable development of wind energy, energy industries have invested in the development of highly efficient wind turbines such as an axial flux permanent magnet (AFPM) generator. The AFPM generator, however, has a history of overheating on the surface of the stator, so that power production decreases significantly. A proper cooling system, therefore, is needed. Although a convective-type cooling system has been developed, the size of the air blower must be increased when the generator’s capacity exceeds 2.5 MW. In this paper, we proposed a newly developed conductive-type cooling system using a heat pipe wound to the stator of a 2.5 MW AFPM generator installed on an offshore wind turbine. The numerical results showed that the temperatures on the stator surface using convective-type cooling system and the proposed conductive-type cooling system at thermal saturation were 60 and 76°C, respectively, which met the requirements for power production. The temperatures of the permanent magnet cased by the radiant heating from the stator surface were 53°C and 66°C, respectively, in each case. As a result, the permanent magnet did not reach the malfunction temperature. Although the cooling temperatures in the case of the conductive-type cooling system were higher than that of the convective-type cooling system, the relatively small size of the water pump and radiators make a light-weight design of the AFPM generator possible.

Keywords: wind turbine, axial flux permanent magnet (AFPM) generator, conductive-type cooling system

Procedia PDF Downloads 299