• Wind and Structures
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• 제33권6호
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• pp.471-480
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• 2021

This present paper leads to investigation of blade-fluid interactions of cambered blade H-Darrieus rotor having EN0005 airfoil blades using comprehensive Computational Fluid Dynamics (CFD) analysis to understand its performance in low wind streams. For several blade azimuthal angle positions, the effects of three different low wind speeds are studied regarding their influence on the blade-fluid interactions of the EN0005 blade rotor. In the prevailing studies by various researchers, such CFD analysis of H-Darrieus rotors are very less, hence it is needed to improve their steady-state performance in low wind velocities. Such a study is also important to obtain important performance insights of such thin cambered blade rotor in its complete rotational cycle. It has been seen that the vortex generated at the suction side of the EN0005 blade rolls back to its leading edge due to the camber of the blade and thus a peak velocity occurs near to the nose position of this blade at its leading edge, which leads to peak performance of this rotor. Again, in the returning phase of the blade, a secondary recirculating vortex is generated that acts on the pressure side of EN0005 blade rotor that increases the performance of this cambered EN0005 blade rotor in its downstream position as well. Here, the aerodynamic performances have been compared considering Standard k-ε and SST k-ω models to check the better suited turbulence model for the cambered EN0005 blade H-Darrieus rotor in low tip speed ratios.

• Korean Journal of Materials Research
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• 제32권5호
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• pp.280-286
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• 2022

Corrosion is a natural, inevitable process, and is one of the world's most serious problems. Losses incurred due to corrosion are extremely expensive for society. Several technological strategies have been explored and implemented to address these losses. The use of inhibitors to prevent corrosion is a common and efficient method to reduce corrosion losses. This review covers Al and Al-composite corrosion inhibitors in chloride-containing solutions, because of their popularity in a broad array of industrial applications. A vast number of studies in the literature detail the common tendency of Al and Al-composites with reinforcements to deteriorate. Accordingly, it is worthwhile to employ inhibitors to protect them, as discussed in the present work. The emphasis is on selecting the smartest corrosion inhibitor and evaluating its performance. According to the study, the most commonly used corrosion inhibitors are 1,4-naphthoquinone (NQ), 1,5-naphthalene diol, 3-amino-1,2,4-triazole-5-thiol (ATAT), ammonium tetrathiotungstate, clotrimazole, amoxicillin, antimicrobial and antifungal drugs. Electrochemical impedance spectroscopy (EIS), potentiodynamic (PDP), and weight loss were among the most commonly used modern electrochemical technologies to test inhibitors' efficacy under environmental conditions.

• Asia pacific journal of information systems
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• 제30권1호
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• pp.21-30
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• 2020

Bitcoin (BTC) is a type of cryptocurrency that supports transaction/payment of virtual money between BTC users without the presence of a central authority or any third party like bank. It uses some cryptographic techniques namely public- and private-keys, digital signature and cryptographic-hash functions, and they are used for making secure transactions and maintaining distributed public ledger called blockchain. In BTC system, each transaction signed by sender is broadcasted over the P2P (Peer-to-Peer) Bitcoin network and a set of such transactions collected over a period is hashed together with the previous block/other values to form a block known as candidate block, where the first block known as genesis-block was created independently. Before a candidate block to be the part of existing blockchain (chaining of blocks), a computation-intensive hard problem needs to be solved. A number of miners try to solve it and a winner earns some BTCs as inspiration. The miners have high computing and hardware resources, and they play key roles in BTC for blockchain formation. This paper mainly analyses the underlying cryptographic techniques, identifies some weaknesses and proposes their enhancements. For these, two modifications of BTC are suggested ― (i) All BTC users must use digital certificates for their authentication and (ii) Winning miner must give signature on the compressed data of a block for authentication of public blocks/blockchain.

• Asia pacific journal of information systems
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• 제33권3호
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• pp.702-736
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• 2023

Artificial Intelligence (AI) and the technologies powered by AI fuel the fourth industrial revolution. Being the primary adopter of such innovations, banking has recently started using the most common AI-based technology, i.e., conversational agents. Although research extensively focuses on this niche area and provides bibliometric understanding for such agents in other industries, a similar review with scientometric insights of the banking literature concerning AI conversational agents is absent till date. Furthermore, in the era following the pandemic, banks are faced with the imperative to provide solutions that align with the changing landscape of remote consumer behavior. As a result, banks are proactively integrating technology-driven solutions, such as automated agents, to effectively address the growing demand for remote customer support. Hence more research is needed to perfect such agents. In order to bridge these existing gaps, the present study undertook a comprehensive examination of two decades' worth of banking literature. A meticulous review was conducted, analyzing approximately 116 papers published from 2003 to 2023. The aim was to provide a scientometric overview of the topic, catering to the research needs of both academic and industrial professionals. Holistically, the study seeks to present a macro-view about the existing trends in AI based banking conversational agents' literature while focusing on quantity, qualitative and structural indicators that are effectively necessary to offer new directions for the AI-based banking solutions. Our study, therefore, presents insights surrounding the literature, using selected techniques related to performance analysis and science mapping.

• Asia pacific journal of information systems
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• 제33권3호
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• pp.652-676
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• 2023

The objective of this study is to provide a deeper understanding of the factors that lead to the development and adoption of AI-based chatbots. We analyze the structural relationship between the organizational (externalities), systematic (fit), and the consumer-related (psychological) factors and their role in the adoption of AI-based chatbots. Founded on the theories of task-technology fit and network externalities, we present a conceptual model overlooking common perception-based theories (e.g., Technology Acceptance Model). We collected 380 responses from Indian banking consumers to test the model using the PLS-SEM method. Interestingly, the findings present a positive impact of all factors on consumers' intention to adopt AI-based chatbots. However, the interplays between these factors provide a mixed perspective for literature. Apart from employing a combination of factors that have been used to study technology adoption, our study explores the importance of externalities and their relationship with fit factors, a unique outlook often overlooked by prior research. Moreover, we offer a clear understanding of latent variables such as trust, and the intricacies of their interplays in a novel context. Thereby, the study offers implications for literature and practice, followed by future research directions.

• Journal of agricultural medicine and community health
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• 제22권1호
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• pp.43-48
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• 1997

To exam infestation rate and removal rate of head louse, we did delousing at 27 primary schools and 19 kindergartens established as an annex to the primary school in Namwon-shi, Jollabuk-do, Korea, from May to December 1995. Total of 3123 subjects were examined ed for the presence of head lice and nits The overall infestation rate was 9.6%, 9.5% in primary school children and 10.1% in kindergarten children. Among 299 infested children, 55 children evaluated by live nit had louse, and 79 children had dead nit. According to distractive research, Ibaek-myon and Songdong-myon revealed high infestation rate of 27.3%, and 21.7% respectively. Infestation rate of primary school was 0 to 50.9%, kindergarten was 0 to 100%. Infestation rate of female children were higher than male in all grades. When we executed one time treatment with PARA$^{(R)}$ aerosol(bioallethrin with piperonyl butoxide), treatment rate of 65.1% was examined, 82.8% was examined in three times of treatment. We concluded that 3 times of treatments interval of 14 days were more effective than one time in the case of treatment of only infested children. In order to prevent the spread of head lice, education of school hygiene and suitable delousing attempts should be executed in the present situation.

• Journal of the Chungcheong Mathematical Society
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• 제28권1호
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• pp.1-12
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• 2015

We present a local convergence analysis for inexact Newton-like method in a Banach space under weaker Lipschitz condition. The convergence ball is enlarged and the estimates on the error distances are more precise under the same computational cost as in earlier studies such as [6, 7, 11, 18]. Some special cases are considered and applications for solving nonlinear systems using the Newton-arithmetic mean method are improved with the new convergence technique.

• Journal of the Korean Vacuum Society
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• 제3권1호
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• pp.71-76
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• 1994

The electrical characteristics of the capacitor dielectric films of amorphous silicon-nit-ride-oxide(ANO) structures are compared with the capacitor dielectric films of oxide-nitride-oxide (ONO) structrues The electrical characteristics of ONO and ANO films were evaluated by high frequency(1 MHz) C-V high frequency C-V after constant voltage stree I-V TDDB and refresh time measurements. ANO films shows good electrical characteristics such as higher total charge to breakdown storage capacitance and longer refresh time than ONO films. Also it makes little difference that leakage current and flat band voltage shyift(ΔVfb)of ANO ana ONO films.

• Proceedings of the Korean Society for Applied Microbiology Conference
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• 한국미생물생명공학회 1979년도 춘계학술대회
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• pp.115.3-115
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• 1979

중금속을 함유한 13종의 질산염을 명 농도별로 첨가하여 주정효모 Saccharomyces cerevisine의 주정생산과 발효작용에 미치는 영향을 조사하였다. 1. 일반적으로 중금속을 함유한 질산염은 그 첨가량이 0.0001mo1. 보다 고농도일수록 Saccharo-myces cerevisiae의 발효작용을 점차 억제하였다. 2. Nickel nitrate, chromium nitrate들의 0.0001 moi.의 첨가는 Saccharomyces cerevisiae의 alcohol 발효작용을 약간촉진시켰다. 3. Cadmium nitrate 0.001mo1. 이상, cupric nit-rate, nickel nitrate, cobalt nitrate 0.01mo1. 이상, 그리고 silver nitrate, mercurous nitrate, manganese nitrate, zinc nitrate, lead nitrate, chromiun nitrate, ferric nitrate, bismuth nitrate 0.1mol. 의 농도에서 Saccharomyces cerevisiae 의 발효작용은 완전히 조지되었다.

• Proceedings of the Korea Air Pollution Research Association Conference
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• 한국대기환경학회 2009년도 추계학술대회 논문집
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• pp.680-681
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• 2009