• Journal of the Korean Society of Safety
• /
• v.39 no.2
• /
• pp.38-43
• /
• 2024

Recently, with the expanding market for electronic devices and electric vehicles, secondary battery usage has been on the rise. Lithium-ion batteries are particularly popular due to their fast charging times and lightweight nature compared to other types of batteries. A secondary battery consists of four components: anode, cathode, electrolyte, and separator. Generally, the positive and negative electrode materials of secondary batteries are composed of an active material, a binder, and a conductive material. Acetylene Black (AB) is utilized to enhance conductivity between active material particles or metal dust collectors, preventing the binder from acting as an insulator. However, when recycling waste batteries that have been subject to high usage, there is a risk of fire and explosion accidents, as accurately identifying the characteristics of Acetylene Black dust proves to be challenging. In this study, the lower explosion limit for Acetylene Black dust with an average particle size of 0.042 ㎛ was determined to be 153.64 mg/L using a Hartmann-type dust explosion device. Notably, the dust did not explode at values below 168 mg, rendering the lower explosion limit calculation unfeasible. Analysis of explosion delay times with varying electrode gaps revealed the shortest delay time at 3 mm, with a noticeable increase in delay times for gaps of 4 mm or greater. The findings offer fundamental data for fire and explosion prevention measures in Acetylene Black waste recycling processes via a predictive model for lower explosion limits and ignition delay time.

• Microbiology and Biotechnology Letters
• /
• v.51 no.3
• /
• pp.223-242
• /
• 2023

In contrast to chemical medicines, biopharmaceuticals exhibit reduced side effects and enhanced therapeutic efficacy. Antibody therapies have significantly advanced since the first monoclonal antibody's approval in 1986, now dominating the pharmaceutical market with seven out of the top 10 biopharmaceuticals. The bispecific antibody has a distinct capability to bind to two antigens simultaneously, unlike conventional monoclonal antibodies that target just one antigen. The notion of bispecific antibodies was initially introduced in 1960, and by 1997, the first symmetrical form of bispecific antibody was successfully produced. Subsequently, extensive research has been conducted on bispecific antibodies, leading to a significant milestone in 2014 when blinatumomab became the first FDA-approved drug to treat acute lymphocytic leukemia. Despite having a relatively shorter history compared to monoclonal antibodies, bispecific antibodies have proven their potential by targeting two antigens simultaneously, thereby rendering them highly effective as anti-cancer drugs. As of 2023, there are a total of 11 globally approved bispecific antibodies, with six of them receiving approval from FDA. In light of the rapidly expanding market for bispecific antibodies, this review article comprehensively explores the attributes, historical background, applications, and market status of bispecific antibodies. Additionally, it sheds light on the present trends in bispecific antibody development, drawing insights from 96 research articles and 105 clinical studies. Excitingly, we anticipate further progress in the development of bispecific antibodies and clinical trials on a global scale, with the aspiration of utilizing them not only in cancer treatment but also for addressing diverse medical conditions.

• Korean Journal of Radiology
• /
• v.1 no.3
• /
• pp.135-141
• /
• 2000

Objective: To compare the clinical utility of the different imaging techniques used for the evaluation of tracheobronchial diseases. Materials and Methods: Forty-one patients with tracheobronchial diseases [tuberculosis (n = 18), bronchogenic carcinoma (n = 10), congenital abnormality (n = 3), post-operative stenosis (n = 2), and others (n = 8)] underwent chest radiography and spiral CT. Two sets of scan data were obtained: one from routine thick-section axial images and the other from thin-section axial images. Multiplanar reconstruction (MPR) and shaded surface display (SSD) images were obtained from thin-section data. Applying a 5-point scale, two observers compared chest radiography, routine CT, thin-section spiral CT, MPR and SSD imaging with regard to the detection, localization, extent, and characterization of a lesion, information on its relationship with adjacent structures, and overall information. Results: SSD images were the most informative with regard to the detection (3.95±0.31), localization (3.95±0.22) and extent of a lesion (3.85±0.42), and overall information (3.83±0.44), while thin-section spiral CT scans provided most information regarding its relationship with adjacent structures (3.56±0.50) and characterization of the lesion (3.51±0.61). Conclusion: SSD images and thin-section spiral CT scans can provide valuable information for the evaluation of tracheobronchial disease.

• The Journal of the Convergence on Culture Technology
• /
• v.10 no.3
• /
• pp.475-487
• /
• 2024

As today's "ninth art", role-playing games recognized by most players due to their surreal themes and sustained reflection on social diseases. Through precise control of story-telling and game visuals, players develop an avatar identification during role-playing game. Based on Lacan's mirror stage theory, a new self-identity mechanism is established under the guidance of role-playing games. As a "player", the subject's interpretation of himself is shifted by the game order, and the subject identifies with the role-playing game while at the same time being structured by the desire of role-playing game. The immersive experience and emotional guidance of role-playing games all point to the most instinctive human desires. The psychoanalytic theory from Lacan's perspective explains the source of players' desire, and the expression of players' desire in the game. It also plays an important role in the emotional rendering and identity aspects of role-playing games. This paper is to establish that role-playing games do have an impact on the player's self-identity through a Lacanian psychoanalytic reading of role-playing games.

• Geomechanics and Engineering
• /
• v.37 no.5
• /
• pp.475-498
• /
• 2024

The prediction of the susceptibility of soil to liquefaction using a limited set of parameters, particularly when dealing with highly unbalanced databases is a challenging problem. The current study focuses on different ensemble learning classification algorithms using highly unbalanced databases of results from in-situ tests; standard penetration test (SPT), shear wave velocity (V_s) test, and cone penetration test (CPT). The input parameters for these datasets consist of earthquake intensity parameters, strong ground motion parameters, and in-situ soil testing parameters. liquefaction index serving as the binary output parameter. After a rigorous comparison with existing literature, extreme gradient boosting (XGBoost), bagging, and random forest (RF) emerge as the most efficient models for liquefaction instance classification across different datasets. Notably, for SPT and V_s-based models, XGBoost exhibits superior performance, followed by Light gradient boosting machine (LightGBM) and Bagging, while for CPT-based models, Bagging ranks highest, followed by Gradient boosting and random forest, with CPT-based models demonstrating lower G_mean(error), rendering them preferable for soil liquefaction susceptibility prediction. Key parameters influencing model performance include internal friction angle of soil (ϕ) and percentage of fines less than 75 µ (F₇₅) for SPT and V_s data and normalized average cone tip resistance (q_c) and peak horizontal ground acceleration (a_max) for CPT data. It was also observed that the addition of V_s measurement to SPT data increased the efficiency of the prediction in comparison to only SPT data. Furthermore, to enhance usability, a graphical user interface (GUI) for seamless classification operations based on provided input parameters was proposed.

• Journal of Ecology and Environment
• /
• v.48 no.2
• /
• pp.163-172
• /
• 2024

Background: Fruit bats are natural carriers of Nipah virus (NiV). The primary objective of this study is to identify potential reservoir species in a selected geographic regions. It is necessary to determine an accurate species identification of the associated reservoir bat species distributed in a specific region. Results: In this study, we collected 20 different bat specimens from the NiV-prone area of the Kushtia district. Among these, 14 were tissue samples (BT-1-14) and six were fecal samples (BF-1-6). We used the mitochondrial gene cytochrome b, one of the most abundant and frequently used genetic markers, for polymerase chain reaction amplification and sequencing. Out of the 20 samples, 12 tissue samples and 2 fecal samples were successfully amplified and sequenced. However, two tissue samples and four fecal samples yielded chimeric sequences, rendering them unsuitable for annotation. The sequences of the successfully amplified samples were compared to those deposited in the National Center for Biotechnology Information database using basic local alignment search tool to identify the bat specimen collected. The study identified six different bat species using both morphological and genetic data, which may carriers of the NiV. Conclusions: Our results suggest that additional research should be conducted to gather more information on fruit bats from different localities across the country. The study contributes to the establishment of appropriate measures for NiV carrying disease control and management.

• Journal of Animal Reproduction and Biotechnology
• /
• v.39 no.2
• /
• pp.105-113
• /
• 2024

Background: Aflatoxin B1 (AFB1) is a toxic metabolite generated by Aspergillus species and is commonly detected during the processing and storage of food; it is considered a group I carcinogen. The hepatotoxic effects, diseases, and mechanisms induced by AFB1 owing to chronic or acute exposure are well documented; however, there is a lack of research on its effects on the intestine, which is a crucial organ in the digestive process. Dogs are often susceptible to chronic AFB1 exposure owing to lack of variation in their diet, unlike humans, thereby rendering them prone to its effects. Therefore, we investigated the effects of AFB1 on canine small intestinal epithelial primary cells (CSIc). Methods: We treated CSIc with various concentrations of AFB1 (0, 1.25, 2.5, 5, 10, 20, 40, and 80 μM) for 24 h and analyzed cell viability and transepithelial-transendothelial electrical resistance (TEER) value. Additionally, we analyzed the mRNA expression of tight junction-related genes (OCLN, CLDN3, TJP1, and MUC2), antioxidant-related genes (CAT and GPX1), and apoptosis-related genes (BCL2, Bax, and TP53). Results: We found a significant decrease in CSIc viability and TEER values after treatment with AFB1 at concentrations of 20 μM or higher. Quantitative polymerase chain reaction analysis indicated a downregulation of OCLN, CLDN3, and TJP1 in CSIc treated with 20 μM or higher concentrations of AFB1. Additionally, AFB1 treatment downregulated CAT, GPX1, and BCL2. Conclusions: Acute exposure of CSIc to AFB1 induces toxicity, and exposure to AFB1 above a certain threshold compromises the barrier integrity of CSIc.

• Journal of the Korea Society of Computer and Information
• /
• v.29 no.8
• /
• pp.23-32
• /
• 2024

NVS (Novel View Synthesis) is a field in computer vision that reconstructs new views of a scene from a set of input views. Real-time rendering and high performance are essential for NVS technology to be effectively utilized in various applications. Recently, 3D-GS (3D Gaussian Splatting) has gained popularity due to its faster training and inference times compared to those of NeRF (Neural Radiance Fields)-based methodologies. However, since 3D-GS reconstructs a 3D (Three-Dimensional) scene by splitting and cloning (Density Control) Gaussian points, the number of Gaussian points continuously increases, causing the model to become heavier as training progresses. To address this issue, we propose two methodologies: 1) Gaussian blending, an improved density control methodology that removes unnecessary Gaussian points, and 2) a performance enhancement methodology using a depth estimation model to minimize the loss in representation caused by the blending of Gaussian points. Experiments on the Tanks and Temples Dataset show that the proposed methodologies reduce the number of Gaussian points by up to 4% while maintaining performance.

• Geomechanics and Engineering
• /
• v.38 no.5
• /
• pp.529-539
• /
• 2024

A high-level nuclear waste (HLW) repository is designed for the long-term disposal of high-level waste. Positioned at depths of 500-1000 meters, it offers an alternative to the insufficient storage space for spent fuels, providing a long-term solution. High-level waste emits heat and radiation, causing structural deterioration, including strength reduction and cracks. Therefore, the use of piezoelectric sensors for structural health monitoring is essential for evaluating the safety of the structure over time. Unlike other structures, the HLW repository restricts human access after the disposal of HLW, rendering sensor replacement impossible. Therefore, it is necessary to assess both the lifespan and suitability of sensors under the disposal conditions in the HLW repository. This study employed an accelerated life test (ALT) to assess the sensor's lifespan under disposal conditions. Failure modes, failure mechanisms, and operational limits were analyzed through accelerated stress test (AST). Additionally, the parameters of the Weibull life probability distribution and the Arrhenius accelerated life model were estimated through statistical methods, including the likelihood ratio test, maximum likelihood estimation, and hypothesis testing. Results confirmed that the sensor's lifespan decreases significantly with the increase in the temperature limit of the HLW repository. The findings of this study can be used for improving sensor lifespan through shielding, development of alternative sensors, or lifespan evaluation of alternative monitoring sensors.

• Journal of Aerospace System Engineering
• /
• v.18 no.4
• /
• pp.10-17
• /
• 2024

Solar-powered unmanned aerial vehicles(SPUAV), which are being actively developed domestically and internationally, generally feature high aspect ratio(AR) wings. These high AR wings necessitate a lightweight design as their weight increases, rendering them susceptible to flutter. Consequently, flutter analysis is critical from the initial design phase. Typically, flutter analysis is conducted using a standard section wing or more precisely through a 3D model. However, due to the extended analysis time required by 3D models, this study opts for a 2D aircraft model. The 2D model computes faster than the 3D model and intuitively secures the flutter boundary. In this study, a structural/aerodynamic force model of the 2D aircraft was established, and the findings were compared with those from a 3D half model. The results showed that the flutter analysis between the 2D model and the 3D half model was similar, within about a 3% margin, thus validating the proposed 2D model's effectiveness.