Kim, Yujin, Liu, Zhan, Jiang, Hao, Ma, T.P., Zheng, Jun-Fei, Chen, Phil, Condo, Eric, Hendrix, Bryan, O'Neill, James A..
2022.
A Study on the Hf0.5Zr0.5O2 Ferroelectric Capacitors fabricated with Hf and Zr Chlorides. 2022 China Semiconductor Technology International Conference (CSTIC). :1–3.
Ferroelectric capacitor memory devices with carbon-free Hf0.5Zr0.5O2 (HZO) ferroelectric films are fabricated and characterized. The HZO ferroelectric films are deposited by ALD at temperatures from 225 to 300°C, with HfCl4 and ZrCl4 as the precursors. Residual chlorine from the precursors is measured and studied systematically with various process temperatures. 10nm HZO films with optimal ALD growth temperature at 275°C exhibit remanent polarization of 25µC/cm2 and cycle endurance of 5×1011. Results will be compared with those from HZO films deposited with carbon containing metal-organic precursors.
Qi, Chao, Nagai, Keita, Ji, Ming, Miyahara, Yu, Sugita, Naohiro, Shinshi, Tadahiko, Nakano, Masaki, Sato, Chiaki.
2022.
A Magnetic Actuator Using PLD-made FePt Thick Film as a Permanent Magnet and Membrane Material for Bi-directional Micropumps. 2022 21st International Conference on Micro and Nanotechnology for Power Generation and Energy Conversion Applications (PowerMEMS). :309–310.
This paper proposes a magnetic actuator using a partially magnetized FePt thick film as a permanent magnet and membrane material for bi-directional micropumps. The magnetized areas act as flux sources, while the magnetized and unmagnetized areas play a role of the membrane part. The mechanical and magnetic characterization results show FePt has a large tensile strength and a lower Young’s modulus than Si crystal, and a comparable remanence to NdFeB. A magnetic pattern transfer technique with a post thermal demagnetization is proposed and experimentally verified to magnetize the FePt partially. Using the proposed magnetic actuator with partially magnetized FePt film is beneficial to simplify the complicated structure and fabrication process of the bi-directional magnetic micropump besides other magnetic MEMS devices.
Sendner, Christoph, Iffländer, Lukas, Schindler, Sebastian, Jobst, Michael, Dmitrienko, Alexandra, Kounev, Samuel.
2022.
Ransomware Detection in Databases through Dynamic Analysis of Query Sequences. 2022 IEEE Conference on Communications and Network Security (CNS). :326–334.
Ransomware is an emerging threat that imposed a \$ 5 billion loss in 2017, rose to \$ 20 billion in 2021, and is predicted to hit \$ 256 billion in 2031. While initially targeting PC (client) platforms, ransomware recently leaped over to server-side databases-starting in January 2017 with the MongoDB Apocalypse attack and continuing in 2020 with 85,000 MySQL instances ransomed. Previous research developed countermeasures against client-side ransomware. However, the problem of server-side database ransomware has received little attention so far. In our work, we aim to bridge this gap and present DIMAQS (Dynamic Identification of Malicious Query Sequences), a novel anti-ransomware solution for databases. DIMAQS performs runtime monitoring of incoming queries and pattern matching using two classification approaches (Colored Petri Nets (CPNs) and Deep Neural Networks (DNNs)) for attack detection. Our system design exhibits several novel techniques like dynamic color generation to efficiently detect malicious query sequences globally (i.e., without limiting detection to distinct user connections). Our proof-of-concept and ready-to-use implementation targets MySQL servers. The evaluation shows high efficiency without false negatives for both approaches and a false positive rate of nearly 0%. Both classifiers show very moderate performance overheads below 6%. We will publish our data sets and implementation, allowing the community to reproduce our tests and results.
Jakubisin, Daniel J., Schutz, Zachary, Davis, Bradley.
2022.
Resilient Underwater Acoustic Communications in the Presence of Interference and Jamming. OCEANS 2022, Hampton Roads. :1–5.
Acoustic communication is a key enabler for underwater Internet of Things networks between autonomous underwater platforms. Underwater Internet of Things networks face a harsh communications environment and limited energy resources which makes them susceptible to interference, whether intentional (i.e., jamming) or unintentional. Resilient, power efficient waveforms and modulation schemes are needed for underwater acoustic communications in order to avoid outages and excessive power drain. We explore the impact of modulation scheme on the resiliency of underwater acoustic communications in the presence of channel impairments, interference, and jamming. In particular, we consider BFSK and OFDM schemes for underwater acoustic communications and assess the utility of Polar coding for strengthening resiliency.
ISSN: 0197-7385
Cheng, Xiang, Yang, Hanchao, Jakubisin, D. J., Tripathi, N., Anderson, G., Wang, A. K., Yang, Y., Reed, J. H..
2022.
5G Physical Layer Resiliency Enhancements with NB-IoT Use Case Study. MILCOM 2022 - 2022 IEEE Military Communications Conference (MILCOM). :379–384.
5G has received significant interest from commercial as well as defense industries. However, resiliency in 5G remains a major concern for its use in military and defense applications. In this paper, we explore physical layer resiliency enhancements for 5G and use narrow-band Internet of Things (NB-IoT) as a study case. Two physical layer modifications, frequency hopping, and direct sequence spreading, are analyzed from the standpoint of implementation and performance. Simulation results show that these techniques are effective to harden the resiliency of the physical layer to interference and jamming. A discussion of protocol considerations for 5G and beyond is provided based on the results.
ISSN: 2155-7586
Eun, Yongsoon, Park, Jaegeun, Jeong, Yechan, Kim, Daehoon, Park, Kyung-Joon.
2022.
A Resiliency Coordinator Against Malicious Attacks for Cyber-Physical Systems. 2022 22nd International Conference on Control, Automation and Systems (ICCAS). :1698–1703.
Resiliency of cyber-physical systems (CPSs) against malicious attacks has been a topic of active research in the past decade due to widely recognized importance. Resilient CPS is capable of tolerating some attacks, operating at a reduced capacity with core functions maintained, and failing gracefully to avoid any catastrophic consequences. Existing work includes an architecture for hierarchical control systems, which is a subset of CPS with wide applicability, that is tailored for resiliency. Namely, the architecture consists of local, network and supervision layers and features such as simplex structure, resource isolation by hypervisors, redundant sensors/actuators, and software defined network capabilities. Existing work also includes methods of ensuring a level of resiliency at each one of the layers, respectively. However, for a holistic system level resiliency, individual methods at each layers must be coordinated in their deployment because all three layers interact for the operation of CPS. For this purpose, a resiliency coordinator for CPS is proposed in this work. The resiliency coordinator is the interconnection of central resiliency coordinator in the supervision layer, network resiliency coordinator in the network layer, and finally, local resiliency coordinators in multiple physical systems that compose the physical layer. We show, by examples, the operation of the resiliency coordinator and illustrate that RC accomplishes a level of attack resiliency greater than the sum of resiliency at each one of the layers separately.
ISSN: 2642-3901