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Modeling, Preparation, and Elemental Doping of Li7La3Zr2O12 Garnet-Type Solid Electrolytes: A Review

  • Cao, Shiyu;Song, Shangbin;Xiang, Xing;Hu, Qing;Zhang, Chi;Xia, Ziwen;Xu, Yinghui;Zha, Wenping;Li, Junyang;Gonzale, Paulina Mercedes;Han, Young-Hwan;Chen, Fei
    • Journal of the Korean Ceramic Society
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    • v.56 no.2
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    • pp.111-129
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    • 2019
  • Recently, all-solid-state batteries (ASSBs) have attracted increasing interest owing to their higher energy density and safety. As the core material of ASSBs, the characteristics of the solid electrolyte largely determine the performance of the battery. Thus far, a variety of inorganic solid electrolytes have been studied, including the NASICON-type, LISICON-type, perovskite-type, garnet-type, glassy solid electrolyte, and so on. The garnet Li7La3Zr2O12 (LLZO) solid electrolyte is one of the most promising candidates because of its excellent comprehensively electrochemical performance. Both, experiments and theoretical calculations, show that cubic LLZO has high room-temperature ionic conductivity and good chemical stability while contacting with the lithium anode and most of the cathode materials. In this paper, the crystal structure, Li-ion transport mechanism, preparation method, and element doping of LLZO are introduced in detail based on the research progress in recent years. Then, the development prospects and challenges of LLZO as applied to ASSBs are discussed.

Implementing Firewall to Mitigate YOYO Attack on Multi Master Cluster Nodes Using Fail2Ban

  • Muhammad Faraz Hyder;Muhammad Umer Farooq;Mustafa Latif;Faizan Razi Khan;Abdul Hameed;Noor Qayyum Khan;M. Ahsan Siddiqui
    • International Journal of Computer Science & Network Security
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    • v.23 no.2
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    • pp.126-132
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    • 2023
  • Web technology is evolving with the passage of time, from a single node server to high availability and then in the form of Kubernetes. In recent years, the research community have been trying to provide high availability in the form of multi master cluster with a solid election algorithm. This is helpful in increasing the resources in the form of pods inside the worker node. There are new impact of known DDoS attack, which is utilizing the resources at its peak, known as Yoyo attack. It is kind of burst attack that can utilize CPU and memory to its limit and provide legit visitors with a bad experience. In this research, we tried to mitigate the Yoyo attack by introducing a firewall at load-balancer level to prevent the attack from going to the cluster network.

Shelf-life Extension of Raw Oyster Crassostrea gigas by Depuration Process (인공정화에 의한 참굴(Crassostrea gigas)의 유통기한 연장)

  • Lee, Do-Ha;Kang, Dong-Min;Park, Seul-Ki;Jeong, Min-Chul;Kang, Min-Gyun;Jo, Du-Min;Lee, Jae-Hwa;Lee, Da-Eun;Sim, Yoon-Ah;Jeong, Geum-Jae;Cho, Kyung-Jin;Kim, Young-Mog
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.53 no.6
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    • pp.842-850
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    • 2020
  • The objective of this study was to evaluate the effect of the depuration process (artificial seawater sterilization using UV light) for extending the shelf life of raw oyster Crassostrea gigas and maintaining food quality. To confirm the effects of depuration, microbiological (viable cell count) and several physiochemical analyses (pH and glycogen levels in shucked oyster and pH, soluble protein, and turbidity in filling water) were carried out during the storage of raw oysters. The results showed that depuration could effectively extend the shelf life (2-3 days) of raw oysters with minimal change in food quality, including pH and glycogen content. Thus, the depuration process proposed in this study could successfully be applied to processing practices for other shellfish to extend their shelf life and contribute to the management of seafood safety issues.

Security Analysis of the Khudra Lightweight Cryptosystem in the Vehicular Ad-hoc Networks

  • Li, Wei;Ge, Chenyu;Gu, Dawu;Liao, Linfeng;Gao, Zhiyong;Shi, Xiujin;Lu, Ting;Liu, Ya;Liu, Zhiqiang
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.12 no.7
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    • pp.3421-3437
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    • 2018
  • With the enlargement of wireless technology, vehicular ad-hoc networks (VANETs) are rising as a hopeful way to realize smart cities and address a lot of vital transportation problems such as road security, convenience, and efficiency. To achieve data confidentiality, integrity and authentication applying lightweight cryptosystems is widely recognized as a rather efficient approach for the VANETs. The Khudra cipher is such a lightweight cryptosystem with a typical Generalized Feistel Network, and supports 80-bit secret key. Up to now, little research of fault analysis has been devoted to attacking Khudra. On the basis of the single nibble-oriented fault model, we propose a differential fault analysis on Khudra. The attack can recover its 80-bit secret key by introducing only 2 faults. The results in this study will provides vital references for the security evaluations of other lightweight ciphers in the VANETs.

Effect of Deformation Temperature on Crystal Texture Formation in Hot Deformed Nanocrystalline SmCo5 Permanent Magnets

  • Ma, Q.;Yue, M.;Lv, W.C.;Zhang, H.G.;Yuan, X.K.;Zhang, D.T.;Zhang, X.F.;Zhang, J.X.;Gao, X.X.
    • Journal of Magnetics
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    • v.21 no.1
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    • pp.25-28
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    • 2016
  • In the present study, bulk anisotropic nanocrystalline $SmCo_5$ magnets were prepared by hot deformation. The effect of deformation temperature on the texture and magnetic properties are presented, based on which the mechanism of plastic deformation and texture formation during the hot deformation process is discussed. Our analyses reveal that deformation temperature is one of the most important parameters that determine the texture of $SmCo_5$ grains. We suggest that diffusion creep plastic deformation occurs during hot deformation, which is very sensitive to the energy gain provided by an increase in temperature.

The Effect of Cooling Rate on the Structure and Mechanical Properties of Fe-3%Mn-(Cr)-(Mo)-C PM Steels

  • Sulowski, Maciej;Cias, Andrzej;Frydrych, Hanna;Frydrych, Jerzy;Olszewska, Irena;Golen, Ryszard;Sowa, Marek
    • Proceedings of the Korean Powder Metallurgy Institute Conference
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    • 2006.09a
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    • pp.563-564
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    • 2006
  • The effect of different cooling rate on the structure and mechanical properties of Fe-3%Mn-(Cr)-(Mo)-0.3%C steels is described. Pre-alloyed Astaloy CrM and CrL, ferromanganese and graphite were used as the starting powders. Following pressing in a rigid die, compacts were sintered at $1120^{\circ}C$ and $1250^{\circ}C$ in $H_2/N_2$ atmospheres and cooled with cooling rates $1.4^{\circ}C/min$ and $6.5^{\circ}C/min$. Convective cooled specimens were subsequently tempered at $200^{\circ}C$ for 60 and 240 minutes.

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