• The Journal of the Convergence on Culture Technology
• /
• v.8 no.5
• /
• pp.541-546
• /
• 2022

This study is to analyze the effect of rapid rise in the rescue activity of suffering on the increase of reactive oxygen species. There is no study that tested the change rate of reactive oxygen species according to the rapid rise in 119 rescue workers, so we want to check the symptoms that appear in rescue workers' bodies. There were 5 subjects, and B, C, and E showed similar values before and after diving: 0.41µmol/L, 0.11µmol/L, and 0.87µmol/L, respectively. However, in subject D, the level of active oxygen rise before and after diving was significantly higher at 1.41µmol/L, which is believed to be due to increased anxiety caused by poor underwater visibility and increased fatigue during rapid ascent after underwater rescue activities. Subject A showed a significantly low increase in active oxygen before and after diving at 0.07µmol/L. The reason seems to be that A is 54 years old and has the most diving experience among the test subjects, and it seems that it is the result of receiving less stress from the poor watch due to the abundant experience of rescue activities as a 119 rescue worker and the skillful underwater activities. Fatigue and anxiety were both high at 4. It is thought that the psychological tension during underwater activities increased fatigue, and the turbidity of the underwater vision raised anxiet.

• The Journal of the Acoustical Society of Korea
• /
• v.42 no.5
• /
• pp.441-451
• /
• 2023

Ultrasound transducers are an essential component of combined photoacoustic and ultrasound imaging systems and play an important role in image evaluation. However, ultrasound transducers are opaque; therefore, light must bypass the ultrasound transducer to reach the target point to produce a photoacoustic image. Providing different paths for the optical and acoustic signals results in a complicated system design, increasing the system volume. To overcome these problems, an optically Transparent Ultrasound Transducer (TUT) was developed. Unlike conventional opaque ultrasound transducers, optically TUT can be fabricated by a variety of manufacturing methods and they are suitable for use with specific piezoelectric elements and serve various purposes. In this study, a comparative analysis of the results of using Lithium Niobate (LNO), Lead Magnesium Niobate-Lead Titanate (PMN-PT), and Polyvinylidene Difluoride (PVDF), which are materials used in piezoelectric element-based TUT. LNO is a piezoelectric element widely used in TUT, and PMN-PT has been actively studied recently with a higher transmission and reception rate than LNO. Existing TUT have lower ultrasound resolution than photoacoustic resolution, but they have recently been manufacturing focused TUT with high ultrasound resolution using PVDF. A comparative analysis of the production results of these TUT was performed.

• KIPS Transactions on Computer and Communication Systems
• /
• v.12 no.8
• /
• pp.253-262
• /
• 2023

E-voting is a concept that includes actions such as kiosk voting at a designated place and internet voting at an unspecified place, and has emerged to alleviate the problem of consuming a lot of resources and costs when conducting offline voting. Using E-voting has many advantages over existing voting systems, such as increased efficiency in voting and ballot counting, reduced costs, increased voting rate, and reduced errors. However, centralized E-voting has not received attention in public elections and voting on corporate agendas because the results of voting cannot be trusted due to concerns about data forgery and modulation and hacking by others. In order to solve this problem, recently, by designing an E-voting system using blockchain, research has been actively conducted to supplement concepts lacking in existing E-voting, such as increasing the reliability of voting information and securing transparency. In this paper, we proposed an electronic voting system that introduced hybrid blockchain that uses public and private blockchains in convergence. A hybrid blockchain can solve the problem of slow transaction processing speed, expensive fee by using a private blockchain, and can supplement for the lack of transparency and data integrity of transactions through a public blockchain. In addition, the proposed system is implemented as BaaS to ensure the ease of type conversion and scalability of blockchain and to provide powerful computing power. BaaS is an abbreviation of Blockchain as a Service, which is one of the cloud computing technologies and means a service that provides a blockchain platform ans software through the internet. In this paper, in order to evaluate the feasibility, the proposed system and domestic and foreign electronic voting-related studies are compared and analyzed in terms of blockchain type, anonymity, verification process, smart contract, performance, and scalability.

• Economic and Environmental Geology
• /
• v.56 no.4
• /
• pp.409-419
• /
• 2023

Acid mine drainage(AMD) treatment is classified as both passive and active treatment. During the treatment, about 5,000 tons of neutralization sludge is generated as a by-product per year in Korea. This study was conducted to evaluate the characteristics of sludge generated from physico·chemical treatment processes as an active treatment from 5 different sources (D, H, S, T, Y) and the possibility of the sludges being recycled. The sludges have a pH range of 5.86 ~ pH 7.89, and a water content range of 51% ~ 82%. Most of particle sizes were less than 25 ㎛. In analysis of inorganic elements, the concentration of Al, Fe, and Mn were between 1,189 mg/kg ~ 129,344 mg/kg, 106,132 mg/kg ~ 338,011 mg/kg, and 3,472 mg/kg ~ 11,743 mg/kg, respectively. The concentration of As and Zn in sludge-T, Cd in sludge-D, Ni in sludge-H, Zn in sludge-S, and Cd in sludge-Y exceeded the soil contamination standards of Korea. The results from 2 separate kinds of leaching test, the Korea Standard Leaching Test(KSLT) and Toxicity Characteristic Leaching Procedure(TCLP), showed that all the sludges met the Korea groundwater standards. From the XRD and SEM-EDS analysis, the peaks of calcite and quartz were found in the sludges. The sludge also had a high proportion of Fe and O, and the majority of the composition was amorphous iron hydroxide.

• Journal of Industrial Convergence
• /
• v.20 no.12
• /
• pp.79-85
• /
• 2022

Recently, a smartphone manufactured on a flexible substrate has been released as an electronic device, and research on a stretchable electronic device is in progress. In this paper, a silicon-based stretchable material is made and used as a substrate to implement and evaluate an optical sensor device using oxide semiconductor. To this end, a substrate that stretches well at room temperature was made using a silicone-based solution rubber, and the elongation of 350% of the material was confirmed, and optical properties such as reflectivity, transmittance, and absorbance were measured. Next, since the surface of these materials is hydrophobic, oxygen-based plasma surface treatment was performed to clean the surface and change the surface to hydrophilicity. After depositing an AZO-based oxide film with vacuum equipment, an Ag electrode was formed using a cotton swab or a metal mast to complete the photosensor. The optoelectronic device analyzed the change in current according to the voltage when light was irradiated and when it was not, and the photocurrent caused by light was observed. In addition, the effect of the optical sensor according to the folding was additionally tested using a bending machine. In the future, we plan to intensively study folding (bending) and stretching optical devices by forming stretchable semiconductor materials and electrodes on stretchable substrates.

• Journal of the Computational Structural Engineering Institute of Korea
• /
• v.36 no.1
• /
• pp.1-7
• /
• 2023

An artificial intelligence (AI) method based on image deep learning is proposed to predict the entire displacement shape of a structure using the feature of partial displacements. The performance of the method was investigated through a structural test of a steel frame. An image-to-image regression (I2IR) training method was developed based on the U-Net layer for image recognition. In the I2IR method, the U-Net is modified to generate images of entire displacement shapes when images of partial displacement shapes of structures are input to the AI network. Furthermore, the training of displacements combined with the location feature was developed so that nodal displacement values with corresponding nodal coordinates could be used in AI training. The proposed training methods can consider correlations between nodal displacements in 3D space, and the accuracy of displacement predictions is improved compared with artificial neural network training methods. Displacements of the steel frame were predicted during the structural tests using the proposed methods and compared with 3D scanning data of displacement shapes. The results show that the proposed AI prediction properly follows the measured displacements using 3D scanning.

• Journal of the Korean Geotechnical Society
• /
• v.39 no.3
• /
• pp.29-40
• /
• 2023

In this study, we investigated the reinforcing effects of waveform micropiles in a stratigraphic setting comprising buried soil, weathered soil, and weathered rock. We conducted a series of field load tests and determined that waveform micropiles exhibited sufficient bearing capacity through frictional resistance in the soil layer and demonstrated favorable constructability in conditions with deep bedrock layers. Moreover, the vertical stiffness of waveform micropiles was approximately 2.2 times higher than that of conventional micropiles when subjected to the same design load. Pile group load tests comprising conventional and waveform micropiles showed that micropiles with higher stiffness carried a greater proportion of the load. Although there was no significant difference in the bearing capacity between conventional and waveform micropiles under the same design load, waveform micropiles with higher stiffness showed a load-carrying capacity 1.7 to 3.2 times greater than that of conventional micropiles. These findings suggest that waveform micropiles can be effectively used for foundation reinforcement and reduce the risk of foundation failure when increased loads due to modifications such as expansion remodeling are expected.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.11 no.2
• /
• pp.112-119
• /
• 2023

In this study, the variations in CO₂ uptake according to the type and amount of alkali-based activator (Ca(OH)₂, CSA) of geopolymer paste were evaluated. As the amount of activator added to the geopolymer paste increased, the fluidity of the paste is decreased and the compressive strength increased. According to the type of activator, it was confirmed that the addition of Ca(OH)₂ had a greater effect on improving the compressive strength than CSA. As a result of changes in chemical properties according to carbonation curing, the amount of C-S-H and C-A-S-H gels produced before carbonation increased as the amount of activator increased, and amount of CaCO₃ produced after carbonation increased. The reactivity of the blast furnace slag and zeolite increased due to the addition of the activator, and the reactivity tended to increase as the amount of addition increased. As a result of CO₂ uptake, 10.3 wt% when Ca(OH)₂ 10 % was added and 8.77 wt% when CSA 10 % was added was confirmed. It increased by 421 % and 388 % respectively, compared to the case where no activator was added.

• Journal of The Korean Association For Science Education
• /
• v.43 no.3
• /
• pp.237-251
• /
• 2023

This study explores the possibility of automated scoring for scientific graph answers by designing an automated scoring model using convolutional neural networks and applying it to students' kinematics graph answers. The researchers prepared 2,200 answers, which were divided into 2,000 training data and 200 validation data. Additionally, 202 student answers were divided into 100 training data and 102 test data. First, in the process of designing an automated scoring model and validating its performance, the automated scoring model was optimized for graph image classification using the answer dataset prepared by the researchers. Next, the automated scoring model was trained using various types of training datasets, and it was used to score the student test dataset. The performance of the automated scoring model has been improved as the amount of training data increased in amount and diversity. Finally, compared to human scoring, the accuracy was 97.06%, the kappa coefficient was 0.957, and the weighted kappa coefficient was 0.968. On the other hand, in the case of answer types that were not included in the training data, the s coring was almos t identical among human s corers however, the automated scoring model performed inaccurately.

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.4
• /
• pp.687-692
• /
• 2023

We analyze the accuracy of emotion analysis of natural language processing deep learning model and propose to use it for emotional content development. After looking at the outline of the GPT-3 model, about 6,000 pieces of dialogue data provided by Aihub were input to 9 emotion categories: 'joy', 'sadness', 'fear', 'anger', 'disgust', and 'surprise'. ', 'interest', 'boredom', and 'pain'. Performance evaluation was conducted using the evaluation indices of accuracy, precision, recall, and F1-score, which are evaluation methods for natural language processing models. As a result of the emotion analysis, the accuracy was over 91%, and in the case of precision, 'fear' and 'pain' showed low values. In the case of reproducibility, a low value was shown in negative emotions, and in the case of 'disgust' in particular, an error appeared due to the lack of data. In the case of previous studies, emotion analysis was mainly used only for polarity analysis divided into positive, negative, and neutral, and there was a limitation in that it was used only in the feedback stage due to its nature. We expand emotion analysis into 9 categories and suggest its use in the development of emotional content considering it from the planning stage. It is expected that more accurate results can be obtained if emotion analysis is performed by additionally collecting more diverse daily conversations through follow-up research.