The objective of this paper is to give a comprehensive introduction to applied cryptography with an engineer or computer scientist in mind. The emphasis is on the knowledge needed to create practical systems which supports integrity, confidentiality, or authenticity. Topics covered includes an introduction to the concepts in cryptography, attacks against cryptographic systems, key use and handling, random bit generation, encryption modes, and message authentication codes. Recommendations on algorithms and further reading is given in the end of the paper. This paper should make the reader able to build, understand and evaluate system descriptions and designs based on the cryptographic components described in the paper.

[서평]「Applied Cryptography」

Silver nanoparticles (AgNPs) can be synthesized from a variety of techniques including physical, chemical and biological routes. They have been widely used as nanomaterials for manufacturing cosmetic and healthcare products, antimicrobial textiles, wound dressings, antitumor drug carriers, etc. due to their excellent antimicrobial properties. Accordingly, AgNPs have gained access into our daily life, and the inevitable human exposure to these nanoparticles has raised concerns about their potential hazards to the environment, health, and safety in recent years. From in vitro cell cultivation tests, AgNPs have been reported to be toxic to several human cell lines including human bronchial epithelial cells, human umbilical vein endothelial cells, red blood cells, human peripheral blood mononuclear cells, immortal human keratinocytes, liver cells, etc. AgNPs induce a dose-, size- and time-dependent cytotoxicity, particularly for those with sizes ≤10 nm. Furthermore, AgNPs can cross the brain blood barrier of mice through the circulation system on the basis of in vivo animal tests. AgNPs tend to accumulate in mice organs such as liver, spleen, kidney and brain following intravenous, intraperitoneal, and intratracheal routes of administration. In this respect, AgNPs are considered a double-edged sword that can eliminate microorganisms but induce cytotoxicity in mammalian cells. This article provides a state-of-the-art review on the synthesis of AgNPs, and their applications in antimicrobial textile fabrics, food packaging films, and wound dressings. Particular attention is paid to the bactericidal activity and cytotoxic effect in mammalian cells.

Bactericidal and Cytotoxic Properties of Silver Nanoparticles.

Solid composite electrolytes (SCEs) that combine the advantages of solid polymer electrolytes (SPEs) and inorganic ceramic electrolytes (ICEs) present acceptable ionic conductivity, high mechanical strength, and favorable interfacial contact with electrodes, which greatly improve the electrochemical performance of all-solid-state batteries compared to single SPEs and ICEs. However, there are many challenges to overcome before the practical application of SCEs, including the low ionic conductivity less than 10-3 S cm-1 at ambient temperature, poor interfacial stability, and high interfacial resistance, which greatly restrict the room temperature performance. Herein, the advances of SCEs applied in all-solid-state lithium batteries are presented, including the Li ion migration mechanism of SCEs, the strategies to enhance the ionic conductivity of SCEs by various morphologies of ICEs, and construction methods of the low resistance and stable interfaces of SCEs with both cathode and anode. Finally, some typical applications of SCEs in lithium batteries are summarized and future development directions are prospected. This work presents how it is quite significant to further enhance the ionic conductivity of SCEs by developing the novel SPEs with the special morphology of ICEs for advanced all-solid-state lithium batteries.

https://onlinelibrary.wiley.com/doi/epdf/10.1002/advs.201903088

Progress and Perspective of Ceramic/Polymer Composite Solid Electrolytes for Lithium Batteries

Safety is the most important requirement for autonomous vehicles; hence, the ultimate challenge of designing an edge computing ecosystem for autonomous vehicles is to deliver enough computing power, redundancy, and security so as to guarantee the safety of autonomous vehicles. Specifically, autonomous driving systems are extremely complex; they tightly integrate many technologies, including sensing, localization, perception, decision making, as well as the smooth interactions with cloud platforms for high-definition (HD) map generation and data storage. These complexities impose numerous challenges for the design of autonomous driving edge computing systems. First, edge computing systems for autonomous driving need to process an enormous amount of data in real time, and often the incoming data from different sensors are highly heterogeneous. Since autonomous driving edge computing systems are mobile, they often have very strict energy consumption restrictions. Thus, it is imperative to deliver sufficient computing power with reasonable energy consumption, to guarantee the safety of autonomous vehicles, even at high speed. Second, in addition to the edge system design, vehicle-to-everything (V2X) provides redundancy for autonomous driving workloads and alleviates stringent performance and energy constraints on the edge side. With V2X, more research is required to define how vehicles cooperate with each other and the infrastructure. Last, safety cannot be guaranteed when security is compromised. Thus, protecting autonomous driving edge computing systems against attacks at different layers of the sensing and computing stack is of paramount concern. In this paper, we review state-of-the-art approaches in these areas as well as explore potential solutions to address these challenges.

Edge Computing for Autonomous Driving: Opportunities and Challenges

Hydrogen atom makes graphene magnetic Graphene has many extraordinary mechanical and electronic properties, but it's not magnetic. To make it so, the simplest strategy is to modify its electronic structure to create unpaired electrons. Researchers can do that by, for example, removing individual carbon atoms or adsorbing hydrogen onto graphene. This has to be done in a very controlled way because of a peculiarity of the graphene's crystal lattice, which consists of two sublattices. Gonzales-Herrero et al. deposited a single hydrogen atom on top of graphene and used scanning tunneling microscopy to detect magnetism on the sublattice lacking the deposited atom (see the Perspective by Hollen and Gupta). Science, this issue p. 437; see also p. 415 Scanning tunneling microscopy shows that a hydrogen atom deposited on graphene makes the complementary sublattice magnetic. [Also see Perspective by Hollen and Gupta] Isolated hydrogen atoms absorbed on graphene are predicted to induce magnetic moments. Here we demonstrate that the adsorption of a single hydrogen atom on graphene induces a magnetic moment characterized by a ~20–millielectron volt spin-split state at the Fermi energy. Our scanning tunneling microscopy (STM) experiments, complemented by first-principles calculations, show that such a spin-polarized state is essentially localized on the carbon sublattice opposite to the one where the hydrogen atom is chemisorbed. This atomically modulated spin texture, which extends several nanometers away from the hydrogen atom, drives the direct coupling between the magnetic moments at unusually long distances. By using the STM tip to manipulate hydrogen atoms with atomic precision, it is possible to tailor the magnetism of selected graphene regions.

/pdf/atomic-scale-control-of-graphene-magnetism-by-using-hydrogen-53d9rq6gri.pdf

Atomic-scale control of graphene magnetism by using hydrogen atoms

Potassium-doped PC71BM for hydrogen storage: Photoelectron spectroscopy and first-principles studies

In this paper we introduce an architecture for hardware acceleration of Software Communication Architecture (SCA) components. Intercommunication, as well as responsiveness and power dissipation, is essential for the components of SCA. Thus, we studied the SCA to explore the hotspot function and optimize its overall performance to not only operate efficiently but also in an energy-efficient way. We spotted the amplifier function takes a significant amount of the execution time which involves single-precision floating-point computation. A case study on the implementation of the amplifier component on the Virtex5 Field-Programmable Gate Array (FPGA) platform is presented. Consequently, we make a comparison of the hardware accelerated amplifier implementation employing a floating-point unit (FPU) engine over pure software implementation with no FPU support. We obtained a speedup of up to 2x faster while minimizing the energy consumption by up to 100% with a power consumption increase of 0.68%, achieving our goal.

/pdf/case-study-on-a-software-communications-architecture-26y5cqfe2v.pdf

Case Study on a Software Communications Architecture Component for Hardware Acceleration

Protecting data is a critical part of life in the modern world. The science of protecting data, known as cryptography, makes use of secret keys to encrypt data in a format that is not easily decipherable. However, most modern cryptography systems use passwords to perform user authentication. These passwords are a weak link in the security chain, and are a common point of attack on cryptography schemes. One alternative to password usage is biometrics: using a person's physical characteristics to verify whom the person is and unlock the data correspondingly. This study focuses on the Cambridge biometric cryptosystem, a system for performing user authentication based on a user's iris data. We converted our implementation of this algorithm from a single-core system to a system that can run on multiple cores. The experiment takes place on an Intel Single Chip Cloud Computer (SCC), an experimental processor created by Intel Labs. A design pattern has been created for the parallelization of software functions using multiple cores. Using this design pattern, two functions in the system were accelerated. The system generated by this acceleration process produced limited computational speedup, but provided results that can be applied to a variety of hardware acceleration problems.

Multi-core Approach towards Efficient Biometric Cryptosystems

This chapter surveys the medium access control (MAC) protocols for satellite networks. Many such protocols have been designed to handle different types of traffic and meet different performance requirements. This chapter gives a comprehensive comparison of these protocols.

Medium Access Control Protocols for Satellite Communications

Unmanned aerial vehicles (UAVs) are widely applied in various fields, which is located by the global position system (GPS) in most cases. However, in the GPS-denied cases, visual localization becomes very important. In complicated environments, such as weak illumination and ground objects changed, visual localization is unstable. This letter presents a UAV visual localization model with a block joint learning network (BJN). Different from the traditional feature extraction-comparison paradigm, the proposed BJN extracts the joint features of the input images at the same time, so as to fully mine the coupling relationship between the multi-source images. Besides this, to overcome the challenges of inconsistency style changes in image matching, the saliency feature based on the attention mechanism and the traditional edge feature operator are introduced in joint feature learning. To evaluate the performance of the proposed model, the experiments on the simulated dataset and the real dataset are given. Both the results on simulated and real datasets indicate that the proposed model is effective on multi-source image matching and UAV visual localization.

Chen Liu

Papers

Potassium-doped PC71BM for hydrogen storage: Photoelectron spectroscopy and first-principles studies

Case Study on a Software Communications Architecture Component for Hardware Acceleration

Multi-core Approach towards Efficient Biometric Cryptosystems

Medium Access Control Protocols for Satellite Communications

Locate Where You Are by Block Joint Learning Network