• Archives of Pharmacal Research
• /
• v.25 no.4
• /
• pp.505-510
• /
• 2002

An improved kinetic assay for prekallikrein activator (PKA), a potential vasodilator, has been developed to be used as an indicator for quality control during production of human albumin preparations. It consists of two reaction stages. In the first stage, PKA and prekallikrein are incubated at $37^{\circ}C$ for 45 min to allow the transformation into kallikrein. Kallikrein, a serine protease, catalyzes the splitting of p-nitroaniline (pNA) from its substrate H-D-Pro-Phe-Arg-pNA(S-2302). The rate at which pNA is released was measured spectrophotometrically at 405 nm. Prekallikrein, a substrate of PKA was purified by DEAE ion-exchange chromatography and the major potential variations in the assay were optimized; pH 8.0 and 150 mM sodium chloride were chosen to give a proper ionic strength. Reaction times in the range of 10 to 360 min provided linear dose-response curves. The concentration of prekallikrein was adjusted to fall between 1:1 and 1:3 dilutions to generate a linear standard calibration curve. Under the optimized conditions, reproducibility was checked. In a precision test, the coefficient of variation (CV) stayed within ${\pm}4%$ and the dose-response curve showed a good correlation (${r^2}=0.999$). An accuracy test with an international standard of PKA afforded a mean recovery of 97.5%.

• Journal of Korean Society of Water and Wastewater
• /
• v.35 no.4
• /
• pp.301-309
• /
• 2021

Chitosan, natural organic polymer, has been applied in water treatment as adsorbent due to non-toxic for human being. The amino group as functional group, can interacts with cation and anion at the same time. The prepared chitosan bead (HCB) was crosslinked to increase chemical stability (HCB-G) and both HCB and HCB-G were prepared to increase physical strength by drying referred to DCB and DCB-G, respectively. The adsorption effect for crosslinking and drying for four types of chitosan bead was tested using pseudo fist order (PFO), pseudo second order (PSO), and intraparticle diffusion model (ID). Regardless of PFO and PSO, the order of K, rate constant, is as followed: HCB > HCB-G > DCB > DCB-G for Cu(II) and phosphate. Drying leading to contraction of bead significantly reduced adsorption rate due to reduce the porosity of chitosan. In addition, crosslingking also negatively effect on adsorption rate. When compared with Cu(II) using hydrogel bead, phosphate showed higher value than Cu(II) for PFO and PSO. The application of ID showed that both hydrogel beads (HCB and HCB-G) obtained a very low R² ranging to 0.37 to 0.81, while R² can be obtained to over 0.9 for DCB and DCB-G, indicting ID is appropriate for low adsorption rate.

• Journal of the Korean Geosynthetics Society
• /
• v.17 no.4
• /
• pp.157-168
• /
• 2018

Recently, the occurrence of typhoons and heavy rainfall is increasing due to climate change. This causes increase in possibility of landslide damages in rural areas. However, in reality, the precise engineering stability assessment studies are still insufficient. Therefore, in order to reduce the landslide damages and effectively manage mountainous areas, the development of disaster prevention techniques is needed. In this study, to analyze the shock absorbing effect of the buffer-spring during application of dynamic impact load in the debris flow protection system, numerical analysis is carried out for each free field of the buffer-spring and the load sharing ratio of the buffer-spring is also examined. In addition, the field applicability is verified by comparison of the tensile strength of the conventional buffer-spring and the wedge type buffer-spring on various magnitudes of dynamic impact load. As a result of the study, it is found that the net-type debris protection system is effective to mitigate loss of properties and human lifes during landslide.

• The Journal of the Korea Contents Association
• /
• v.19 no.7
• /
• pp.166-175
• /
• 2019

The constitution of traditional medicine is distinguished from modern medicine. Sasang medicine describe the constitution which is classified as functional intensity of the lung, spleen, liver and kidney. The functional strength of each part of the human body is not the same in each constitution, and this imbalance is considered as a major factor of the disease. Ayurveda is identified the balance of the three dosha in our body is the basis of health maintenance. The reason for the illness is due to the imbalance among vata which express energy metabolism, pitta which plays a role in metabolism and digestion, and kapha which controls body temperature. The two theories which include knowing the characteristics and trends of diseases according to their constitution, the approach of treatment and the health care of daily life. They are also considered as convergent area about treatment methods in the modern society where individual characteristics and lifestyle are emphasized. The purpose of this study is to understand the concept of constitutional basis for increasing patient satisfaction and to help diversity of treatment in preventive medical area by comparing and analyzing the theory of Sasang and Ayurveda.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.19 no.11
• /
• pp.42-48
• /
• 2020

The agricultural tractor is a multi-purpose vehicle, which is frequently used in the agricultural field. It must be highly reliable in terms of human safety. Design and analysis of agricultural tractors must be performed using actual agricultural workload to maintain high reliability. Additionally, the frequency with which various components and systems are used must also be taken into consideration. In this study, a tractor is built to measure its workload in the actual field. Further, the measured load was analyzed for various farming tasks. The range of ratios of consumed power to engine power was measured to be 42.6%-87.2%, 75.1%-97%, 26.5%-59.2% for a plow, rotary, and harvest tasks, respectively. The results were fed into a transmission simulation model to analyze the strength and life of the transmission components. We conclude that a more reliable product can be constructed by incorporating the transmission analyses using the actual load.

• The Korean Journal of Franchise Management
• /
• v.11 no.3
• /
• pp.43-57
• /
• 2020

Purpose: Along with the trend increasing dining-out and enjoying variety of menu, dessert café has been introduced as a new type of food service provider and grown up rapidly. We need to verify structural relationship that dessert café environment influences overall quality and brand image and loyalty. Research design, data, and methodology: This study seeks to understand how in-café environment influence overall quality, brand image and loyalty directly and indirectly based on SOR theory. We examine detail effect of in-café environment on overall quality and brand image and subsequently loyalty. Sample data were collected from 563 online survey panels and analyzed by using SmartPLS 3.2.9. Result: The results indicates that all sub-dimensions of in-café environment influences positively overall quality. While, menu and atmosphere make positive impact on brand image. price, food and beverage quality, employee service do not affect significantly brand image. Further, overall quality influences positively brand image and both overall quality and brand image affect positively loyalty. In addition, overall quality plays full mediator role in relationship among price, food and beverage quality, employee service and brand image. Conclusions: Dessert café should differentiate itself from competitors through physical and non-physical environments which are likely to influence overall quality. As overall quality mediates between environment and brand image and influences loyalty, dessert café is required to communicate strength of functional quality and service quality aggressively. Additionally, favorable brand image affecting loyalty is required to be dominated in advance as the market is likely to be segmented along with its growth.

• KSII Transactions on Internet and Information Systems (TIIS)
• /
• v.15 no.5
• /
• pp.1814-1828
• /
• 2021

Low-light image enhancement is a key technique to overcome the quality degradation of photos taken under scotopic vision illumination conditions. The degradation includes low brightness, low contrast, and outstanding noise, which would seriously affect the vision of the human eye recognition ability and subsequent image processing. In this paper, we propose an approach based on deep learning and Retinex theory to enhance the low-light image, which includes image decomposition, illumination prediction, image reconstruction, and image optimization. The first three parts can reconstruct the enhanced image that suffers from low-resolution. To reduce the noise of the enhanced image and improve the image quality, a super-resolution algorithm based on the Laplacian pyramid network is introduced to optimize the image. The Laplacian pyramid network can improve the resolution of the enhanced image through multiple feature extraction and deconvolution operations. Furthermore, a combination loss function is explored in the network training stage to improve the efficiency of the algorithm. Extensive experiments and comprehensive evaluations demonstrate the strength of the proposed method, the result is closer to the real-world scene in lightness, color, and details. Besides, experiments also demonstrate that the proposed method with the single low-light image can achieve the same effect as multi-exposure image fusion algorithm and no ghost is introduced.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.26 no.3
• /
• pp.403-411
• /
• 2022

A motion-based sports game uses a motion sensor or a camera to exercise based on body movements, and it is possible to obtain exercise effects such as improving physical strength while enjoying the game. In prior works, various studies such as usability evaluation has been conducted on motion-based sports games. However, there has been no discussion about how the exercise effect is exerted on users when experiencing motion-based sports games as individual or team play. This study compared the user's exercise effects by analyzing the user's ECG (Electrocardiogram) sensor and the Kinect sensor's skeletal information using Nintendo Switch game that is played individually and as a team. In this paper, the experimental design and method, the quantitative measurement results based on ECG and Kinect, and the results of the post-test subjective measurement are discussed.

• Journal of the Society of Naval Architects of Korea
• /
• v.59 no.1
• /
• pp.39-45
• /
• 2022

Normal strategy of structure optimization procedure has been minimum cost or weight design. Minimum weight design satisfying an allowable stress has been used for the ship and offshore structure, but minimum cost design could be used for the case of high human cost. Natural frequency analysis and forced vibration one have been used for the strength estimation of marine structures. For the case of high precision experiment facilities in marine field, the structure has normally enough margin in allowable stress aspect and sometimes needs high natural frequency of structure to obtain very high precise experiment results. It is not easy to obtain a structure design with high natural frequency, since the natural frequency depend on the stiffness to mass ratio of the structure and increase of structural stiffness ordinary accompanies the increase of mass. It is further difficult at the grillage structure design using the profiles, because the properties of profiles are not continuous but discrete, and resource of profiles are limited at the design of grillage structure. In this paper, the grillage structure design system under the constraint of high natural frequency is introduced. The design system adopted genetic algorithm to realize optimization procedure and can be used at the design of the experimental facilities of marine field such as a towing carriage, PMM, test frame, measuring frame and rotating arm.

• Geomechanics and Engineering
• /
• v.28 no.3
• /
• pp.283-298
• /
• 2022

Landslides triggered by the combination of heavy precipitation and anthropological disturbance in hilly areas cause severe damage to human lives, properties, and infrastructure constructions. A comprehensive investigation of the influencing factors and failure mechanisms of landslides are significant for disaster mitigation and prevention. This paper utilized the combination of detailed geological investigation, physical experimental testing as well as numerical modelling to determine the failure mechanism, and proposed a countermeasures of the Lantian landslide occurred on 2, July 2017. The results reveal that the Lantian landslide is a catastrophic reactivated slide which occurred in an active tectonic region in Southwest China. Because of the unique geological settings, the fully to highly weathered basalts in the study area with well-developed fractures favored the rainwater infiltration, which is the beneficial to slide reactivation. Engineering excavation and heavy precipitation are the main triggering factors to activate the slide motion. Two failure stages have been identified in the landslide. The first phase involves a shallow mass collapse originated at the upper slopes, which extends from the road to platform at rear part, which is triggered by excavation in the landslide region. Subjected to the following prolonged rainfall from 19 June to 2 July, 2017, the pore water pressure of the slope continually increased, and the groundwater table successively rise, resulting in a significant decrease of soil strength which leads to successive large-scale deep slide. Thereinto, the shallow collapse played a significant role in the formation of the deep slide. Based on the formation mechanisms of the landslide, detailed engineering mitigation measures, involving slope cutting, anchor cable frame, shotcrete and anchorage, retaining wall and intercepting ditch were suggested to reduce the future failure risk of the landslide.