• Mass Spectrometry Letters
• /
• v.10 no.1
• /
• pp.18-26
• /
• 2019

We developed a bioanalytical method for simultaneous determination of nine NBOMe derivatives (25H-NBOMe, 25B-NBOMe, 25E-NBOMe, 25N-NBOMe, 25C-NBOH, 25I-NBOH, 25B-NBF, 25C-NBF, and 25I-NBF) in human plasma using liquid chromatography tandem mass spectrometry (LC-MS/MS). Human plasma samples were pre-treated using solid-phase extraction. Separation was achieved on a C18 column under gradient elution using a mobile phase containing 0.1% formic acid in acetonitrile and 0.1% formic acid in water at a flow rate of 0.3 mL/min. Mass detection was performed in the positive ion mode using multiple reaction monitoring. The calibration range was 1-100 ng/mL for all quantitative analytes, with a correlation coefficient greater than 0.99. The intra- and inter-day precision and accuracy varied from 0.85 to 6.92% and from 90.19 to 108.69%, respectively. The recovery ranged from 86.36 to 118.52%, and the matrix effects ranged from 27.09 to 99.72%. The stability was acceptable in various conditions. The LC-MS/MS method was validated for linearity, accuracy, precision, matrix effects, recovery and stability in accordance with the FDA guidance. The proposed method is suitable for reliable and robust routine screening and analysis of nine NBOMe derivatives in forensic field.

• Journal of Korea Water Resources Association
• /
• v.54 no.6
• /
• pp.381-393
• /
• 2021

As part of the National Disaster Management Research Institute's Official Development Assistance (ODA) projects for transferring new technologies in the field of disaster-safety management, a flood forecasting and warning system was established in 2019 targeting the Borikhan in the Namxan River Basin in Bolikhamxai Province, Laos. In the target area, which is an ungauged small and medium river basin, observation stations for real-time monitoring of rainfall and runoff and alarm stations were installed, and a software that performs real-time data management and flood forecasting and warning functions was also developed. In order to establish a flood warning standard and develop a nomograph for flood prediction, hydraulic and hydrological analysis was performed based on the 30-year annual maximum daily rainfall data and river morphology survey results in the target area. This paper introduces the process and methodology used in this study, and presents the results of the system's applicability review based on the data observed and collected in 2020 after system installation.

• Journal of Korean Society on Water Environment
• /
• v.27 no.5
• /
• pp.699-709
• /
• 2011

The uses of multi-dimensional hydrodynamic and water quality models are increasing to support a sustainable management of large dam reservoirs in Korea. Any modeling study requires selection of a proper spatial dimension of the model based on the characteristics of spatial variability of concerned simulation variables. For example, a laterally averaged two-dimensional (2D) model, which has been widely used in many large dam reservoirs in Korea, assumes that the lateral variations of hydrodynamic and water quality variables are negligible. However, there has been limited studies to give a justification of the assumption. The objectives of this study were to present the characteristics of spatial variations of water quality variables through intensive field monitoring in Daechung Reservoir, and provide information on a proper spatial dimension for different water quality parameters. The monitoring results showed that the lateral variations of water temperature are marginal, but those of DO, pH, and conductivity could be significant depending on the hydrological conditions and local algal biomass. In particular, the phytoplankton (Chl-a) and nutrient concentrations showed a significant lateral variation at R2 (Daejeongri) during low flow periods in 2008 possibly because of slow lateral mixing of tributary inflow from So-oak Stream and wind driven patchiness.

• Journal of the Korea Institute of Information Security & Cryptology
• /
• v.22 no.6
• /
• pp.1315-1324
• /
• 2012

Security visualization is a form of the data visualization techniques in the field of network security by using security-related events so that it is quickly and easily to understand network traffic flow and security situation. In particular, the security visualization that detects the abnormal situation of network visualizing connections between two endpoints is a novel approach to detect unknown attack patterns and to reduce monitoring overhead in packets monitoring technique. However, the session-based visualization doesn't notice a difference between normal traffic and attacks that they are composed of similar connection pattern. Therefore, in this paper, we propose an efficient session-based visualization method for analyzing and detecting between normal server activities and attacks by using the IP address splitting and port attributes analysis. The proposed method can actually be used to detect and analyze the network security with the existing security tools because there is no dependence on other security monitoring methods. And also, it is helpful for network administrator to rapidly analyze the security status of managed network.

• Animal Bioscience
• /
• v.34 no.8
• /
• pp.1253-1270
• /
• 2021

Assessment of male fertility is based on the evaluation of sperm. Semen evaluation measures various sperm quality parameters as fertility indicators. However, semen evaluation has limitations, and it requires the advancement and application of strict quality control methods to interpret the results. This article reviews the recent advances in evaluating various sperm-specific quality characteristics and methodologies, with the help of different assays to assess sperm-fertility status. Sperm evaluation methods that include conventional microscopic methods, computer-assisted sperm analyzers (CASA), and flow cytometric analysis, provide precise information related to sperm morphology and function. Moreover, profiling fertility-related biomarkers in sperm or seminal plasma can be helpful in predicting fertility. Identification of different sperm proteins and diagnosis of DNA damage has positively contributed to the existing pool of knowledge about sperm physiology and molecular anomalies associated with different infertility issues in males. Advances in methods and sperm-specific evaluation has subsequently resulted in a better understanding of sperm biology that has improved the diagnosis and clinical management of male factor infertility. Accurate sperm evaluation is of paramount importance in the application of artificial insemination and assisted reproductive technology. However, no single test can precisely determine fertility; the selection of an appropriate test or a set of tests and parameters is required to accurately determine the fertility of specific animal species. Therefore, a need to further calibrate the CASA and advance the gene expression tests is recommended for faster and field-level applications.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.1
• /
• pp.81-86
• /
• 2021

The cosmetic industry is technology-intensive in the field of fine chemistry and continues to grow globally. The functional aspects have been mainly emphasized in the past to increase the market share in these cosmetics industries. Recently, however, efforts have been made to attract the attention of consumers to the visual effects as well as the excellent performance of cosmetics at home and abroad. Accordingly, cosmetic manufacturers are trying various technologies that encapsulate the cosmetic emulsion and modify the shape, color, and texture of the emulsion capsule. The basic and easiest method of encapsulating emulsion is dropping the emulsion through the nozzle from emulsion storage. On the other hand, the existing method of encapsulating emulsion has a limit in reducing the size of the capsule. In this study, the limit was shown by theory and numerical analysis method, and the emulsion encapsulation phenomena occurring in the micro-channel were studied to apply microfluidics as an alternative.

• Tunnel and Underground Space
• /
• v.32 no.3
• /
• pp.219-230
• /
• 2022

The Geo-Reservoir Experimental Analogue Technology (GREAT) cell was designed to recreate the thermal-hydro-mechanical conditions of deep subsurface in the laboratory. This apparatus can generate a polyaxial stress field using lateral loading elements, which rotate around the longitudinal axis of a sample and is capable of performing a fluid flow test for samples containing fractures. In the present study, numerical simulations were carried out for triaxial compression tests using the GREAT cell and the mechanical behavior of samples under different conditions of lateral loading was investigated. We simulated an actual case, in which triaxial compression tests were conducted for a polymer sample without fractures, and compared the results between the numerical analysis and experiment. The surface strain (circumferential strain) of the sample was analyzed for equal and non-equal horizontal confining pressures. The results of the comparison showed a good consistency. Additionally, for synthetic cases with a fracture, we investigated the effect of the friction and type of fracture surface on the deformation behavior.

• Composites Research
• /
• v.34 no.6
• /
• pp.350-356
• /
• 2021

When a ship with a planing line operates or turns in a straight line, the floating position and trim change according to the speed, and a large resistance is generated on the hull. In this paper, the resistance to a planing line was estimated through the computational fluid dynamics of a leisure boat with improved hull weight and durability by applying a carbon composite material to the hull. The resistance performance of the bow and stern of the 18ft class leisure boat was checked and the flow field of the entire vessel was estimated, and the stability of the planing line was confirmed by comparing the resistance of each trim through numerical analysis. In addition, it was confirmed that the designed planing line could withstand it sufficiently because the force applied to the hull was not large, and The stability of the boat was analyzed by calculating the wavelength of the wave and the length of the ship as the ratio of gravity to the inertial force and checking how much force the rolling occurred.

• Wind and Structures
• /
• v.34 no.2
• /
• pp.215-230
• /
• 2022

Majority of transmission line system failures at many locations worldwide have been caused by severe localized wind events in the form of tornadoes and downbursts. This study evaluates the structural response of two different transmission line systems under equivalent F2 tornadoes obtained from real incidents. Two multi-span self-supported transmission line systems are considered in the study. Nonlinear three-dimensional finite element models are developed for both systems. The finite element models simulate six spans and five towers. Computational Fluid Dynamics (CFD) simulations are used to develop the tornado wind fields. Using a proper scaling method for geometry and velocity, full-scale tornado flow fields for the Stockton, KS, 2005 and Goshen County WY, 2009 are developed and considered together with a previously developed tornado wind field. The tornado wind profiles are obtained in terms of tangential, radial, and axial velocities. The simulated tornadoes are then normalized to the maximum velocity value for F2 tornadoes in order to compare the effect of different tornadoes having an equal magnitude. The tornado wind fields are incorporated into a three-dimensional finite element model. By varying the location of the tornado relative to the transmission line systems, base shears of the tower of interest and peak internal forces in the tower members are evaluated. Sensitivity analysis is conducted to assess the variation of the structural behaviour of the studied transmission lines associated with the location of the tornado relative to the tower of interest. The tornado-induced forces in both lines due to the three different normalized tornadoes are compared with corresponding values evaluated using the simplified load case method recently incorporated in the ASCE-74 (2020) guidelines, which was previously developed based on the research conducted at Western University.

• International Journal of Computer Science & Network Security
• /
• v.22 no.11
• /
• pp.222-228
• /
• 2022

In today's era of digital technologies, the problem of religious communication in the cyberspace is being actualized, since the globality and accessibility of the WWW makes it one of the most effective and promising channels for transmitting various kinds of messages, including those of a religious nature. Today, religious organizations and movements pay the closest attention to the virtual media space, not only using it to attract new followers, but also for religious PR, image-making and branding, informing the world about themselves through news from the life of the organization and its followers. An equally important form of electronic communication in the online sphere is currently the interaction of various religious movements and religious cultures in general, or the dialogue of confessions in particular. Research in the digital space makes it possible to identify important trends in religious spheres based on the analysis of the flow of information on the Internet, to demonstrate the specifics of individual media outlets and the consequences of their activities for interreligious dialogue, to study the role of the Internet in changing religious beliefs, the possibility of changing religious identity, retrospective development of religious enlightenment at the turn of the century, to determine the vectors of possible interreligious interaction and discuss the role of digital technologies in the work of religious structures, to state the need to continue an active dialogue between representatives of religious movements, to hold expert seminars on interreligious dialogue on a regular basis, and to record the risks generated by the digital space. Thus, the coronavirus pandemic served as a background and context, a litmus test and a catalyst for accelerating and intensifying interreligious, interfaith dialogue and dialogue between religious organizations and society.