• Journal of the Korean Society of Safety
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• v.35 no.6
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• pp.25-31
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• 2020

Boiling Liquid Expanding Vapor Explosion(BLEVE) can cause not only economic damage to the plant but also serious casualties. LPG accidents account for 89.6 percent of all accidents caused by gas leaks in Korea over the past nine years, while casualties from accidents also account for 73 percent of all accidents, according to statistics from the Korea Gas Safety Corporation. In addition, a potential explosion and a fire accident from one LPG storage tank may affect the nearby storage tanks, causing secondary and tertiary damage (domino effect). The safety distance standards for LPG used by LPG workplaces, charging stations, and homes in Korea have become stricter following the explosion of LPG charging stations in Bucheon. The safety distance regulation is divided into regulations based on the distance damage and the risk including frequency. This study suggests two approaches to optimizing the safety distance based on the just consequence and risk including frequencies. Using the Phast 7.2 Risk Assessment software by DNV GL, the explosion overpressure and heat radiation were derived according to the distance caused by BLEVE in the worst-case scenario, and accident and damage probability were derived by considering the probit function and domino effect. In addition, the safety distance between LPG tanks or LPG charging stations was derived to minimize damage effects by utilizing these measures.

• Journal of Forest and Environmental Science
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• v.37 no.1
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• pp.35-43
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• 2021

The interspecific hybrid of Salix caprea and Salix gracilistyla has never been identified or studied in Korea. Accordingly, this study investigated the flower morphological characteristics of the interspecific hybrid between S. caprea and S. gracilistyla and compared the interspecific hybrid with S. caprea and S. gracilistyla, respectively. The female flowers were investigated for 12 characteristics and the male flowers were investigated for nine. For the female flowers, those of the hybrids were larger than those of S. caprea and S. gracilistyla in terms of catkin length (CL), bract length (BL), and bract width (BW). The hybrids are intermediates between S. caprea and S. gracilistyla in terms of ovary length, width, and stipitate length as well as gland length (GL). For the male flowers, those of the hybrids were bigger than those of S. caprea and S. gracilistyla in terms of CL, BL, and BW. The hybrids are intermediates between S. caprea and S. gracilistyla in terms of catkin width and stamen length (SL). A principal component analysis (PCA) of the female data showed that the first principal component (PC) explained 57.5% of the total variation. The first PC highly correlated the ovary stipitate and pistil style lengths. The analysis was divided into three groups of S. caprea, S. gracilistyla, and the hybrid by the first PC. The results of a PCA of the male data showed that the first PC explained 35.7% of the total variation. The first PC highly correlated with the adelphous SL and was divided into three groups of S. caprea, S. gracilistyla, and the hybrid. The results of the discriminant analysis showed that S. caprea, S. gracilistyla, and the hybrid were distinguishable by flower morphological characteristics. Therefore, the hybrid was distinctly separated from S. caprea and S. gracilistyla by flower characteristics.

• International Journal of Naval Architecture and Ocean Engineering
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• v.12 no.1
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• pp.241-257
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• 2020

The rapid proliferation of oil/gas drilling and wind turbine installations with jack-up rig-formed structures increases structural safety requirements, due to the greater risks of operational collisions during use of these structures. Therefore, current industrial practices and regulations have tended to increase the required accidental collision design loads (impact energies) for jack-up rigs. However, the existing simplified design approach tends to be limited to the design and prediction of local members due to the difficulty in applying the increased uniform impact energy to a brace member without regard for the member's position. It is therefore necessary to define accidental load estimation in terms of a reasonable collision scenario and its application to the structural response analysis. We found by a collision probabilistic approach that the kinetic energy ranged from a minimum of 9 MJ to a maximum 1049 MJ. Only 6% of these values are less than the 35 MJ recommendation of DNV-GL (2013). This study assumed and applied a representative design load of 196.2 MN for an impact load of 20,000 tons. Based on this design load, the detailed design of a leg structure was numerically verified via an FE analysis comprising three categories: linear analysis, buckling analysis and progressive collapse analysis. Based on the numerical results from this analysis, it was possible to predict the collapse mode and position of each member in relation to the collision load. This study provided a collision strength assessment between attendant vessels and a jack-up rig based on probabilistic collision scenarios and nonlinear structural analysis. The numerical results of this study also afforded reasonable evaluation criteria and specific evaluation procedures.

• The Journal of Korean Physical Therapy
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• v.33 no.6
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• pp.272-277
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• 2021

Purpose: The purpose of this study is to confirm the effect of static stretching of the plantar flexor for 5 minutes on balance and ankle muscle activity when walking in young adults. Methods: This study experimented on 20 healthy college students without vestibular and musculoskeletal diseases. Subjects performed static stretching intervention of plantar flexor for 5 minutes on a stretch board set at 15° to 25° Balance was measured four times before intervention (pre), after intervention (post), 5 minutes after intervention (post 5 min), 10 minutes after intervention (post 10 min), and ankle muscle activity was measured during walking. For the analysis and post hoc analysis, one-way Repeated Measure ANOVA and Fisher's LSD (Last Significant Difference) was performed to find out the change in balance and the activity of ankle muscles before static stretching, pre, post, post 5 minutes rest, post 10 minutes rest. Results: There was no significant difference in weight distribution index (WDI) in balance, but stability index (ST) showed a significant difference, and there was also a significant difference in correlation pre, post, post 5min rest, post 10 minutes rest (p<0.05). There was no significant difference in ankle muscle activity during walking in Tibialis anterior (TA), Medial gastrocnemius (GM), and Lateral gastrocnemius (GL) (p>0.05). Conclusion: The stability index (ST) increased significantly immediately after static stretching and decreased after 5 minutes. After static stretching, at least 5 minutes of rest are required to restore balance.

• Structural Engineering and Mechanics
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• v.81 no.5
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• pp.617-631
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• 2022

In this paper the viscoelastic responses of four experimental steel-concrete composite beams subjected to highly variable environmental conditions are investigated by means of a finite element (FE) model. Concrete specimens submitted to stepped stress changes are also evaluated to validate the current formulations. Here, two well-known approaches commonly used to solve the viscoelastic constitutive relationship for concrete are employed. The first approach directly solves the integral-type form of the constitutive equation at the macroscopic level, in which aging is included by updating material properties. The second approach is postulated from a rate-type law based on an age-independent Generalized Kelvin rheological model together with Solidification Theory, using a micromechanical based approach. Thus, conceptually both approaches include concrete hardening in two different manners. The aim of this work is to compare and analyze the numerical prediction in terms of long-term deflections of the studied specimens according to both approaches. To accomplish this goal, the performance of several well-known model codes for concrete creep and shrinkage such as ACI 209, CEB-MC90, CEB-MC99, B3, GL 2000 and FIB-2010 are evaluated by means of statistical bias indicators. It is shown that both approaches with minor differences acceptably match the long-term experimental deflection and are able to capture complex oscillatory responses due to variable temperature and relative humidity. Nevertheless, the use of an age-independent scheme as proposed by Solidification Theory may be computationally more advantageous.

• International Journal of Computer Science & Network Security
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• v.22 no.11
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• pp.213-221
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• 2022

Intelligent Character Recognition System for Account Payable (ICRS AP) Automation represents the process of capturing text from scanned invoices and extracting the key fields from invoices and storing the captured fields into properly structured document format. ICRS plays a very critical role in invoice data streamlining, we are interested in data like Vendor Name, Purchase Order Number, Due Date, Total Amount, Payee Name, etc. As companies attempt to cut costs and upgrade their processes, accounts payable (A/P) is an example of a paper-intensive procedure. Invoice processing is a possible candidate for digitization. Most of the companies dealing with an enormous number of invoices, these manual invoice matching procedures start to show their limitations. Receiving a paper invoice and matching it to a purchase order (PO) and general ledger (GL) code can be difficult for businesses. Lack of automation leads to more serious company issues such as accruals for financial close, excessive labor costs, and a lack of insight into corporate expenditures. The proposed system offers tighter control on their invoice processing to make a better and more appropriate decision. AP automation solutions provide tighter controls, quicker clearances, smart payments, and real-time access to transactional data, allowing financial managers to make better and wiser decisions for the bottom line of their organizations. An Intelligent Character Recognition System for AP Automation is a process of extricating fields like Vendor Name, Purchase Order Number, Due Date, Total Amount, Payee Name, etc. based on their x-axis and y-axis position coordinates.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.56 no.1
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• pp.21-27
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• 2023

Lotus Nelumbo nucifera seed protein (LSP) was isolated by alkaline solubilization after removing fat and phenolics by hexane and ethanol treatment. Antioxidant peptides from LSP were produced with Alcalase^® and pepsin and hydroxyl radical scavenging activities were determined. LSP-Alcalase^® hydrolysates showed higher hydroxyl radical scavenging activity than LSP-pepsin hydrolysates. To purify antioxidant peptides, LSP-Alcalase^® hydrolysates were subjected to high performance liquid chromatography (HPLC) separation on the C18 column and the active fraction was further purified using a Superdex^TM peptide 10/300 GL column. Finally, the active fraction (F8-2) was evaluated for antioxidant activities by 2,2-diphenyl-1-picrylhydrazyl (DPPH), hydroxyl radical scavenging, and oxygen radical absorbance capacity (ORAC) assays. The EC₅₀ values of the F8-2 were 105.81±0.02 ㎍/mL for DPPH and 32.26±0.02 ㎍/mL for hydroxyl radical and the F8-2 exhibited 7.22 μM trolox equivalent (TE)/100 ㎍ F8-2. Glutathione (GSH), which is a positive control, showed EC₅₀ values of 19.87±0.01 ㎍/mL for DPPH and 15.95±0.03 ㎍/mL for hydroxyl radical and an ORAC value of 14.17±0.03 μM TE/100 ㎍ GSH. Finally, sixteen peptides were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Among them, Ile-Tyr and Leu-Tyr showed higher antioxidant scores.

• Molecules and Cells
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• v.46 no.8
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• pp.513-525
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• 2023

Orange carotenoid protein (OCP) of photosynthetic cyanobacteria binds to ketocarotenoids noncovalently and absorbs excess light to protect the host organism from light-induced oxidative damage. Herein, we found that mutating valine 40 in the α3 helix of Gloeocapsa sp. PCC 7513 (GlOCP1) resulted in blue- or red-shifts of 6-20 nm in the absorption maxima of the lit forms. We analyzed the origins of absorption maxima shifts by integrating X-ray crystallography, homology modeling, molecular dynamics simulations, and hybrid quantum mechanics/molecular mechanics calculations. Our analysis suggested that the single residue mutations alter the polar environment surrounding the bound canthaxanthin, thereby modulating the degree of charge transfer in the photoexcited state of the chromophore. Our integrated investigations reveal the mechanism of color adaptation specific to OCPs and suggest a design principle for color-specific photoswitches.

• International Journal of Internet, Broadcasting and Communication
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• v.15 no.3
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• pp.219-230
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• 2023

With the development of autonomous driving technology, as the use of software in vehicles increases, the complexity of the system increases and the difficulty of development increases. Developments that meet ISO 26262 must be carried out to reduce the malfunctions that may occur in vehicles where the system is becoming more complex. ISO 26262 for the functional safety of the vehicle industry proposes to consider functional safety from the design stage to all stages of development. Specifically at the software level, the requirements to be complied with during development and the requirements to be complied with during verification are defined. However, it is not clearly expressed about specific design methods or development methods, and it is necessary to supplement development guidelines. The importance of analysis and verification of requirements is increasing due to the development of technology and the increase of system complexity. The vehicle industry must carry out developments that meet functional safety requirements while carrying out various development activities. We propose a process that reflects the perspective of system engineering to meet the smooth application and developmentrequirements of ISO 26262. In addition, the safety analysis/verification FMEA processforthe safety of the proposed ISO 26262 function was conducted based on the FCAS (Forward Collision Avoidance Assist System) function applied to autonomous vehicles and the results were confirmed. In addition, the safety analysis/verification FMEA process for the safety of the proposed ISO 26262 function was conducted based on the FCAS (Forward Collision Avoidance Assist System) function applied to the advanced driver assistance system and the results were confirmed.

• Food Science of Animal Resources
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• v.43 no.5
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• pp.914-937
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• 2023

The objective of this study was to establish a multi-residue quantitative method for the analysis of anthelmintic and antiprotozoal drugs in various livestock products (beef, pork, and chicken) using ultra-high-performance liquid chromatography-tandem mass spectrometry. Each compound performed validation at three different levels i.e., 0.5, 1, and 2× the maximum residue limit according to the CODEX guidelines (CAC/GL 71-2009). This study was conducted according to the modified quick, easy, cheap, effective, rugged, and safe procedure. The matrix-matched calibrations gave correlation coefficients >0.98, and the obtained recoveries were in the range of 60.2%-119.9%, with coefficients of variation ≤32.0%. Furthermore, the detection and quantification limits of the method were in the ranges of 0.03-3.2 and 0.1-9.7 ㎍/kg, respectively. Moreover, a survey of residual anthelmintic and antiprotozoal drugs was also carried out in 30 samples of beef, pork, and chicken collected in Korea. Toltrazuril sulfone was detected in all three samples. Thus, our results indicated that the developed method is suitable for determining the anthelmintic and antiprotozoal drug contents in livestock products.