• Journal of Microbiology and Biotechnology
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• v.23 no.8
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• pp.1140-1146
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• 2013

Bioelectrochemical systems (BESs) have been suggested as a new technology for wastewater treatment while accomplishing energy and chemical generation. This study describes the performance of BESs based on mixed culture that are capable of reducing carbon dioxide to acetate. The cathode potential was a critical factor that affected the performance of the BESs. The rate of acetate production increased as the electrode potential became more negative, from 0.38 mM $d^{-1}$ (-900 mV vs. Ag/AgCl) to 2.35 mM $d^{-1}$ (-1,100 mV), while the electron recovery efficiency of carbon dioxide reduction to acetate increased from 53.6% to 89.5%. The microbial population was dominated by relatives of Acetobacterium woodii when a methanogenic inhibitor was added to the BESs initially.

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.24-32
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• 2018

Nanocellulose was surface-functionalized toward the applications in enhanced oil recovery (EOR) as a green alternative. The focus of this paper is on the effect of this material based nanofluid (NF) on foam lamella stabilization through studying its bubble breakup dynamics and flow behaviors in constricted mircofluidic devices. The NF stabilized foam produced an improved flow resistance across the capillary largely due to the capillary trapped bubbles at the contraction. The "snap-off" caused the NF stabilized foam to produce finer textured bubbles, which can migrate readily forward to the deep porous media, as revealed by the pressure profiles.

• Journal of the Korea Society of Computer and Information
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• v.23 no.1
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• pp.57-66
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• 2018

It is known that a single-key and a related-key attacks on AES-128 are possible for at most 7 and 8 rounds, respectively. The security of CMAC, a typical block-cipher-based MAC algorithm, has very high possibility of inheriting the security of the underlying block cipher. Since the attacks on the underlying block cipher can be applied directly to the first block of CMAC, the current security margin is not sufficient compared to what the designers of AES claimed. In this paper, we consider HMAC-DM-AES-128 as an alternative to CMAC-AES-128 and analyze its security for reduced rounds of AES-128. For 2-round AES-128, HMAC-DM-AES-128 requires the precomputation phase time complexity of $2^{97}$ AES, the online phase time complexity of $2^{98.68}$ AES and the data complexity of $2^{98}$ blocks. Our work is meaningful in the point that it is the first security analysis of MAC based on hash modes of AES.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.10 no.1
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• pp.99-110
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• 2000

암호 시스템에서 가장 중요한 정보는 키 정보이다. 키가 손상되거나 유실되면 모든정보가 유실되기 때문이다. 키 위탁 시스템이란 유사시의 상황에 대비해서 키를 특정한 위탁기관에 위탁함으로써 정보를 암호의 오용이나 키의 분실로부터 보호 할 수 있는 시스템이다. 키 위탁 시스템은 유사시에 확실하게 키를 복원할 수 있어야 하며, 동시에 복구 정보의 안전한 보관이 이루어져야 한다. 그리고 위탁 시스템으로 인해 사생활이 침해되지 않는 것 또한 중요하다. 이러한 요구사항들은 서로 상충되는 점이 있기 때문에 모든 요구사항을 만족시키는 키 위탁 시스템을 설계하기는 매우 어렵다. 본 논문에서는 키 위탁 시스템 설계시에 고려해야 할 요소를 도출하고, 키 위탁 시스템 설계 및 분석을 위한 모델을 제안한다. 이 모델은 정의된 요구사항을 만족시키는 키 복구 시스템을 설계할 때 유용하게 사용될 수 있으며, 이미 제안된 키 복구 시스템을 분석하는 도구로 활용될 수 있다.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.20 no.1
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• pp.35-44
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• 2020

The growing use of public blockchain-based virtual cryptocurrency calls for secure management of blockchain account information managed through cryptocurrency wallet programs. The previously proposed wallet program has high security in terms of managing an account's private key, but low security in managing an account's recovery phrase. Therefore, in this paper, we propose a safe management system of blockchain account recovery string based on the new user authentication method using the user's mobile device information and OTP technique to overcome the problem of the existing account recovery string management method. It also conducts an analysis of the proposed blockchain account recovery string management system based on the expected behavior scenario.

• Journal of Preventive Medicine and Public Health
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• v.57 no.3
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• pp.197-211
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• 2024

Objectives: Recovery from drug addiction often poses challenges for the recovering person. The coping mechanisms employed by these individuals to resist temptations and manage stress play a key role in the healing process. This study was conducted to explore the coping strategies or techniques that individuals with addiction use to handle stress and temptation while undergoing treatment. Methods: A qualitative meta-synthesis approach was utilized to critically evaluate relevant qualitative research. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines were used for article selection, with these standards applied to 4 academic databases: Scopus, PubMed, ProQuest, and CINAHL. The present review included studies published between 2014 and 2023, selected based on pre-established inclusion criteria. The quality of the studies was assessed using the Critical Appraisal Skills Programme Qualitative Studies Checklist. This review was registered with the International Prospective Register of Systematic Reviews (PROSPERO) under the registration number CRD42024497789. Results: The analysis of 13 qualifying qualitative articles revealed 5 major themes illustrating the coping mechanisms employed in the pursuit of recovery by individuals who use drugs. These themes include seeking social support, as well as psychological coping strategies, spiritual experiences, professional interventions, and the enhancement of awareness. Conclusions: Among individuals with drug addiction, coping mechanisms are crucial for resisting stress and temptations throughout the recovery process. Healthcare professionals, as medical specialists, can establish more thorough and effective plans to support these patients on their path to recovery.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1675-1680
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• 2014

A peroxopolyoxotungsten-based ionic hybrid was synthesized by anion-change of peroxopolyoxometalate (POM) $PW_4O{_{24}}^{3-}$ with dicationic long-chain alkyl imidazolium ionic liquids. The characterization was conducted by FT-IR, TGA, $^1H$-NMR and CHN Elemental analyses. Its catalytic performance was evaluated by the epoxidation of soybean oil with $H_2O_2$ under solvent-free condition, including testing of organic cations influence, catalytic reusability and reaction conditions. The catalyst was proved to be a highly efficient recyclable catalyst for epoxidation of various vegetable oils with $H_2O_2$, showing high $H_2O_2$ utilization efficiency, high catalytic activity, convenient recovery and good reuse ability.

• Journal of Climate Change Research
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• v.2 no.3
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• pp.143-159
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• 2011

Projects applying the CDM methodology AM0035 of the $SF_6$ Emission Reductions in Electrical Grids should provide direct monitoring of all the key parameters that are related to estimation of baseline and project emissions including detailed explanations of key operating conditions and procedures, and an explanation addressing uncertainty as the result of EB meeting 41. Through this study, recovery ratio during maintenance, purity of $SF_6$ before and after disposal, replacing, loss rate of $SF_6$ before and after reclamation, leakage emission from electricity consumption and fossil fuel combustion, considered conservatively the key parameter of various monitoring. Consequently, confirmed the reduction in the amount of reduction due to the baseline emission decrease, project emission increase.

• Journal of Ginseng Research
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• v.45 no.6
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• pp.642-653
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• 2021

Background: Effective strategies are dramatically needed to prevent and improve the recovery from myocardial ischemia and reperfusion (I/R) injury. Direct interactions between the mitochondria and endoplasmic reticulum (ER) during heart diseases have been recently investigated. This study was designed to explore the cardioprotective effects of gypenoside XVII (GP-17) against I/R injury. The roles of ER stress, mitochondrial injury, and their crosstalk within I/R injury and in GP-17einduced cardioprotection are also explored. Methods: Cardiac contractility function was recorded in Langendorff-perfused rat hearts. The effects of GP-17 on mitochondrial function including mitochondrial permeability transition pore opening, reactive oxygen species production, and respiratory function were determined using fluorescence detection kits on mitochondria isolated from the rat hearts. H9c2 cardiomyocytes were used to explore the effects of GP-17 on hypoxia/reoxygenation. Results: We found that GP-17 inhibits myocardial apoptosis, reduces cardiac dysfunction, and improves contractile recovery in rat hearts. Our results also demonstrate that apoptosis induced by I/R is predominantly mediated by ER stress and associated with mitochondrial injury. Moreover, the cardioprotective effects of GP-17 are controlled by the PI3K/AKT and P38 signaling pathways. Conclusion: GP-17 inhibits I/R-induced mitochondrial injury by delaying the onset of ER stress through the PI3K/AKT and P38 signaling pathways.

• Membrane and Water Treatment
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• v.1 no.1
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• pp.83-92
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• 2010

To improve the antifouling characteristics of polypropylene hollow fiber microporous membranes in a submerged membrane-bioreactor for wastewater treatment, the surface-modification was conducted by Ar plasma treatment. Surface hydrophilicity was assessed by water contact angle measurements. The advancing and receding water contact angles reduced after the surface modification, and hysteresis between the advancing and receding water contact angles was enlarged after Ar plasma treatment due to the increased surface roughness after surface plasma treatment. After continuous operation in a submerged membrane-bioreactor for about 55 h, the flux recovery after water cleaning and the flux ratio after fouling were improved by 20.0 and 143.0%, while the reduction of flux was reduced by 28.6% for the surface modified membrane after 1 min Ar plasma treatment, compared to those of the unmodified membrane. Morphological observations showed that the mean membrane pore size after Ar plasma treatment reduced as a result of the deposition of the etched species; after it was used in the submerged membrane-bioreactor, the further decline of the mean membrane pore size was caused by the deposition of foulants. X-ray photoelectron spectroscopy and infrared spectroscopy confirmed that proteins and polysaccharide-like substances were the main foulants in the precipitate.