• Journal of Internet Computing and Services
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• v.20 no.2
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• pp.93-100
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• 2019

Recently, in various business fields, companies are concentrating on providing chatbot services to various environments by adding artificial intelligence to existing messenger platforms. Organizations in the field of job placement also require chatbot services to improve the quality of employment counseling services and to solve the problem of agent management. A text-based general chatbot classifies input user sentences into learned sentences and provides appropriate answers to users. Recently, user sentences inputted to chatbots are inputted as short texts due to the activation of social network services. Therefore, performance improvement of short text classification can contribute to improvement of chatbot service performance. In this paper, we propose T-EBOW (Translation-Extended Bag Of Words), which is a method to add translation information as well as concept information of existing researches in order to strengthen the short text classification for employment chatbot. The performance evaluation results of the T-EBOW applied to the machine learning classification model are superior to those of the conventional method.

• Korean Journal of Agricultural Science
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• v.49 no.1
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• pp.137-149
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• 2022

We investigated the effects of Cirsium japonicum var. maackii (CJM) against oxidative stress-induced C6 glial cells and cognitive impairment in mice. To evaluate the anti-oxidative effect of the extract and fractions from CJM, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT), reactive oxygen species (ROS), and nitric oxide (NO) assays were conducted in H₂O₂-treated C6 glial cells. Furthermore, we identified the protective mechanisms of CJM with a scopolamine-treated mice model. The results revealed that H₂O₂ decreased the cell viability in C6 glial cells, indicating that H₂O₂ induced oxidative stress in glial cells. However, CJM fractions significantly increased cell viability in H₂O₂-treated C6 glial cells, which suggested that CJM protected against oxidative stress. CJM extract and fractions also reduced ROS and NO production, which were increased by H₂O₂ in C6 glial cells. In particular, the EtOAc fraction from CJM (EACJM) effectively protected against oxidative stress by increasing the cell viability and decreasing ROS and NO. Therefore, we carried out further in vivo experiments with EACJM. Scopolamine caused increases of ROS, thiobarbituric acid reactive substances (TBARS), and NO production. However, EACJM effectively alleviated ROS, TBARS, and NO levels compared to scopolamine-injected mice. In addition, EACJM up-regulated protein expressions of superoxide dismutase and glutathione peroxidase, indicating that EACJM enhanced the antioxidative system. Our results demonstrated that CJM had protective effects against oxidative stress in glial cells and memory dysfunction in mice. Based on these results, we propose that CJM could be a potential AD preventive and therapeutic agent.

• Journal of Korea Society of Digital Industry and Information Management
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• v.19 no.2
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• pp.135-145
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• 2023

ChatGPT is an artificial intelligence-based conversation agent developed by OpenAI using natural language processing technology. In this study, an empirical study was conducted on incumbent teachers on the intention to use the newly emerged Chat GPT. First, we studied how accuracy, entertainment, system accessibility, perceived usefulness, and perceived ease of use affect ChatGPT's acceptance intention. In addition, we analyzed whether perceived usefulness and perceived ease of use differ in the intention to accept depending on the digital technology of teachers. As a result of the study, the suitability of the structural equation model was generally good. Accuracy and entertainment were found to have a significant effect on perceived usefulness, and system accessibility was found to have a significant effect on perceived ease of use. In the analysis of teachers' digital technology control effects, it was found that perceived usefulness and perceived ease of use had a control effect between acceptance intentions. It was found that the group with high digital skills of teachers was strongly intended to accept the service regardless of perceived usefulness and ease of use. In the group with low digital skills of teachers, it is thought that ChatGPT's service shows the acceptance intention only when the perceived usefulness and ease of use are high. Therefore, in the group with low digital technology, it is necessary to seek teaching activities such as the development of instructional models using ChatGPT.

• Journal of Microbiology and Biotechnology
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• v.33 no.11
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• pp.1484-1494
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• 2023

NUC1 (Nutraceutical compound 1) is an ethanol extract composed of a formulation based on medicinal herbs traditionally used for the treatment of arthritis in Korea and China. This study investigated the therapeutic effects of NUC1 on osteoarthritis (OA). The protective effect of NUC1 on OA was tested in a rabbit model of collagenase-induced arthritis (CIA) for 4 weeks. Results were compared among four groups (n = 9 per group): the normal group (untreated), the CIA group (vehicle control), the NUC1 group (CIA rabbits treated with 200 mg/kg NUC1), and the JOINS group (positive control, CIA rabbits treated with 200 mg/kg JOINS tablet). NUC1 significantly inhibited NO production (p < 0.05 at 125 ㎍/ml, p < 0.01 at 250 ㎍/ml, and p < 0.001 at 500 ㎍/ml) and iNOS expression in macrophages, in a concentration-dependent manner. NUC1 also inhibited the release and protein expression of MMP-1, 3, and 13, in TNF-α-induced chondrosarcoma cells in a concentration-dependent manner. In vivo, the MMP-1 and MMP-3 levels in synovial fluids were significantly (p < 0.05) lower in NUC1 group (77.50 ± 20.56 and 22.50 ± 7.39 pg/ml, respectively) than in the CIA group (148.33 ± 68.58 and 77.50 ± 20.46 pg/ml, respectively). Also, in histopathological, NUC1 ameliorated articular cartilage damage in OA by increasing the abundance of chondrocytes and proteoglycan in the articular cartilage. Thus, NUC1 showed promise as a potential therapeutic agent, and it can be generalized to a broader study population in different OA animal models.

• IMMUNE NETWORK
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• v.23 no.3
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• pp.29.1-29.23
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• 2023

Cholesterol (CL) is required for various biomolecular production processes, including those of cell membrane components. Therefore, to meet these needs, CL is converted into various derivatives. Among these derivatives is cholesterol sulfate (CS), a naturally produced CL derivative by the sulfotransferase family 2B1 (SULT2B1), which is widely present in human plasma. CS is involved in cell membrane stabilization, blood clotting, keratinocyte differentiation, and TCR nanocluster deformation. This study shows that treatment of T cells with CS resulted in the decreased surface expression of some surface T-cell proteins and reduced IL-2 release. Furthermore, T cells treated with CS significantly reduced lipid raft contents and membrane CLs. Surprisingly, using the electron microscope, we also observed that CS led to the disruption of T-cell microvilli, releasing small microvilli particles containing TCRs and other microvillar proteins. However, in vivo, T cells with CS showed aberrant migration to high endothelial venules and limited infiltrating splenic T-cell zones compared with the untreated T cells. Additionally, we observed significant alleviation of atopic dermatitis in mice injected with CS in the animal model. Based on these results, we conclude that CS is an immunosuppressive natural lipid that impairs TCR signaling by disrupting microvillar function in T cells, suggesting its usefulness as a therapeutic agent for alleviating T-cell-mediated hypersensitivity and a potential target for treating autoimmune diseases.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.34 no.1
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• pp.21-29
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• 2024

With the development of ICT and network, security management of IT infrastructure that has grown in size is becoming very difficult. Many companies and public institutions are having difficulty managing system and network security. In addition, as the complexity of hardware and software grows, it is becoming almost impossible for a person to manage all security. Therefore, AI is essential for network security management. However, since it is very dangerous to operate an attack model in a real network environment, cybersecurity emulation research was conducted through reinforcement learning by implementing a real-life network environment. To this end, this study applied reinforcement learning to the network environment, and as the learning progressed, the agent accurately identified the vulnerability of the network. When a network vulnerability is detected through AI, automated customized response becomes possible.

• The Korean Journal of Physiology and Pharmacology
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• v.16 no.4
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• pp.273-279
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• 2012

Busulfan is an antineoplastic agent with a narrow therapeutic window. A post-hoc population pharmacokinetic analysis of a prospective randomized trial for comparison of four-times daily versus once-daily intravenous busulfan was carried out to search for predictive factors of intravenous busulfan (iBu) pharmacokinetics (PK). In this study the population PK of iBu was characterized to provide suitable dosing recommendations. Patients were randomized to receive iBu, either as 0.8 mg/kg every 6 h or 3.2 mg/kg daily over 4 days prior to hematopoietic stem cell transplantation. In total, 295 busulfan concentrations were analyzed with NONMEM. Actual body weight and sex were significant covariates affecting the PK of iBu. Sixty patients were included in the study (all Korean; 23 women, 37 men; mean [SD] age, 36.5 [10.9] years; weight, 66.5 [11.3] kg). Population estimates for a typical patient weighing 65 kg were: clearance (CL) 7.6 l/h and volume of distribution (Vd) 32.2 l for men and 29.1 L for women. Inter-individual random variabilities of CL and $V_d$ were 16% and 9%. Based on a CL estimate from the final PK model, a simple dosage scheme to achieve the target $AUC_{0-inf}$ (defined as median AUC0-inf with a once-daily dosage) of 26.18 $mg/l{\cdot}hr$, was proposed: $24.79{\cdot}ABW^{0.5}mg$ q24h, where ABW represents the actual body weight in kilograms. The dosing scheme reduced the unexplained interindividual variabilities of CL and Vd of iBu with ABW being a significant covariate affecting clearance of iBU. We propose a new simple dosing scheme for iBu based only on ABW.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.10A
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• pp.1131-1138
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• 2004

In Hierarchical Mobile Ipv6 (HMIPv6) networks, the mobility anchor point (MAP) handles binding update (BU) procedures locally to reduce signaling overhead for mobility. However, as the number of mobile nodes (MNs) handled by the MAP increases, the MAP suffers from the overhead not only to handle signaling traffic but also to Process data tunneling traffic. Therefore, it is important to control the number of MNs serviced by the MAP, in order to mitigate the burden of the MAP. We propose an adaptive load control scheme, which consists of two sub-algorithms: threshold-based admission control algorithm and session-to-mobility ratio (SMR) based replacement algorithm. When the number of MNs at a MAP reaches to the full capacity, the MAP replaces an existing MN at the MAP, whose SMR is high, with an MN that just requests binding update. The replaced MN is redirected to its home agent. We analyze the proposed load control scheme using the .Markov chain model in terms of the new MN and the ongoing MN blocking probabilities. Numerical results indicate that the above probabilities are lowered significantly compared to the threshold-based admission control alone.

• Journal of the Korea Society for Simulation
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• v.33 no.2
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• pp.37-44
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• 2024

The Korean Helicopter Development Program has successfully introduced the Surion helicopter, a versatile multi-domain operational aircraft that replaces the aging UH-1 and 500MD helicopters. Specifically designed for maneuverability, the Surion plays a crucial role in low-altitude tactical maneuvers for personnel transportation and specific missions, emphasizing the helicopter's survivability. Despite the significance of its low-altitude tactical maneuver capability, there is a notable gap in research focusing on multi-mission tactical maneuvers that consider the risk factors associated with deploying the Surion in the presence of enemy air defenses. This study addresses this gap by exploring a method to enhance the Surion's low-altitude maneuvering paths, incorporating information about enemy air defenses. Leveraging the Proximal Policy Optimization (PPO) algorithm, a reinforcement learning-based approach, the research aims to optimize the helicopter's path planning. Visualized experiments were conducted using a Surion model implemented in the Unity environment and ML-Agents library. The proposed method resulted in a rapid and stable policy convergence for generating optimal maneuvering paths for the Surion. The experiments, based on two key criteria, "operation time" and "minimum damage," revealed distinct optimal paths. This divergence suggests the potential for effective tactical maneuvers in low-altitude situations, considering the risk factors associated with enemy air defenses. Importantly, the Surion's capability for remote control in all directions enhances its adaptability in complex operational environments.

• Journal of KIISE:Computing Practices and Letters
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• v.6 no.4
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• pp.421-429
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• 2000

In present, ATM integrated switching system has been developed to a mixed modules that complexed switching system including maintenance, operation based on B-ISDN/LAN service and plug-in module, , which runs on workstation computer system. Meanwhile, workstation has HMI operation system feature including file system management, time management, graphic processing, TMN agent function. The workstation has communicated with between ATM switching module and clients. This computer system architecture has much burden messages communication among processes or processor. These messages communication consume system resources which are socket, message queue, IO device files, regular files, and so on. Therefore, in this paper we proposed new performance modeling with this system architecture. We will analyze the system bottleneck and improve system performance. In addition, in the future, the system has many additional features should be migrated to workstation system, we need previously to evaluate system bottleneck and redesign it. In performance model, we use queueing network model and the simulation package is used PDQ and C-program.