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」

Developing efficient sensor materials with superior performance for selective, fast and sensitive detection of gases and volatile organic compounds (VOCs) is essential for human health and environmental protection, through monitoring indoor and outdoor air pollutions, managing industrial processes, controlling food quality and assisting early diagnosis of diseases. Metal–organic frameworks (MOFs) are a unique type of crystalline and porous solid material constructed from metal nodes (metal ions or clusters) and functional organic ligands. They have been investigated extensively for possible use as high performance sensors for the detection of many different gases and VOCs in recent years, due to their large surface area, tunable pore size, functionalizable sites and intriguing properties, such as electrical conductivity, magnetism, ferroelectricity, luminescence and chromism. The high porosity of MOFs allows them to interact strongly with various analytes, including gases and VOCs, thus resulting in easily measurable responses to different physicochemical parameters. Although much of the recent work on MOF-based luminescent sensors have been summarized in several excellent reviews (up to 2018), a comprehensive overview of these materials for sensing gases and VOCs based on chemiresistive, magnetic, ferroelectric, and colorimertic mechanisms is missing. In this review, we highlight the most recent progress in developing MOF sensing and switching materials with an emphasis on sensing mechanisms based on electricity, magnetism, ferroelectricity and chromism. We provide a comprehensive analysis on the MOF–analyte interactions in these processes, which play a key role in the sensing performance of the MOF-based sensors and switches. We discuss in detail possible applications of MOF-based sensing and switching materials in detecting oxygen, water vapor, toxic industrial gases (such as hydrogen sulfide, ammonia, sulfur dioxide, nitrous oxide, carbon oxides and carbon disulfide) and VOCs (such as aromatic and aliphatic hydrocarbons, ketones, alcohols, aldehydes, chlorinated hydrocarbons and N,N′-dimethylformamide). Overall, this review serves as a timely source of information and provides insight for the future development of advanced MOF materials as next-generation gas and VOC sensors.

Functional metal–organic frameworks as effective sensors of gases and volatile compounds

Carbon and graphene quantum dots (CQDs and GQDs), known as zero-dimensional (0D) nanomaterials, have been attracting increasing attention in sensing and bioimaging. Their unique electronic, fluores...

Review of Carbon and Graphene Quantum Dots for Sensing

Small carbon nanoparticles are an emerging member of the carbonaceous nanomaterial family and have been subsequently named as “carbon quantum dots” or “carbon nanodots”. Generally, carbon quantum dots are a type of spherical or sphere-like nanoparticles of less than 10 nm in size. Due to their unique properties, for example, size-dependent fluorescence, non-toxicity, biocompatibility, and easy accessibility, carbon quantum dots possess a great many potential applications in a range of fields from chemical sensing and imaging to catalysis and drug delivery, and thus are appealing to a number of researchers in nanoscience and nanotechnology. In this review, we give a brief introduction of the synthesis and fundamental properties of carbon quantum dots, then present their applications in metal ion sensing in detail along with illustrating the related mechanisms, and finally come up with some challenges currently faced and future outlooks for this fascinating carbon material. We hope this review could be helpful for readers who are preparing to join and/or have joined the research field of carbon quantum dots.

Carbon quantum dot-based nanoprobes for metal ion detection

Recent progress in the synthesis of graphene and derived materials for next generation electrodes of high performance lithium ion batteries

Comments on Fast architecture for decimal digit multiplication

Salivary pH is one of the indicators of the dental health of a person. To enable fast and easy dental health observations, we developed a flexible capacitive pH sensor using graphene oxide (GO) sensing layer on the laser-induced graphene (LIG) electrode produced from a polyimide (PI) film acting both as LIG precursor material and substrate. Cyclic voltammetry (CV) was used as a measurement technique. The sensor showed the characteristic CV behavior of capacitive elements, and it presented an unequivocal response to the pH level in saliva. The area under the CV curve was used to extract the specific capacitance (C s ) and correlated to the corresponding pH level measured.

Laser-fabricated flexible nanographene-based sensor for pH detection in saliva

Radio frequency identification (RFID) security is a relevant matter. The wide spread of RFID applications in the general society and the persistent attempts to safeguard it confirm it, especially since its use involves payments and the store or transmission of sensitive information. In this contribution, we present an innovative solution for improving the security of RFID passive tags through the use of a screen printed button, that allows the reception and transmission only when a certain level of physical pressure normal to its plane is applied. The materials and fabrication technology used demonstrate an easy to implement and cost-effective system, valuable in several scenarios where the user has straight contact with the tags and where its usage is direct and intentional.

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Screen Printed Security-Button for Radio Frequency Identification Tags

The configuration of electrodes and guards, as well as the shielding arrangement, determines the resolution and sensing field of an ECT sensor. In this work, a full study of the response of a 12-electrode sensor is carried out by means of 2D and 3D Finite Element Method based simulations, and the influence of the design parameters on the sensitivity and quality of the reconstructed images is stated.

Influence of design parameters of ECT sensors on the quality of reconstructed images

In this work, a novel method for the formation of Electrical Capacitance Tomography (ECT) images is presented. This method is based on the modification of the classical algebraic superposition of sensitivity maps, weighted with the inter-electrode capacitance measurements, which is the basis of most of the existing image reconstruction algorithms. The proposed approach replaces this superposition with the scalar multiplication of partial images generated considering only the data corresponding to fixed source electrodes. Results obtained with this proposed method show that the quality of the images can be improved without any image post-processing, which is very interesting especially for real-time applications.

Diego P. Morales

Papers

Comments on Fast architecture for decimal digit multiplication

Laser-fabricated flexible nanographene-based sensor for pH detection in saliva

Screen Printed Security-Button for Radio Frequency Identification Tags

Influence of design parameters of ECT sensors on the quality of reconstructed images

An Imaging Method for Electrical Capacitance Tomography Based on Projections Multiplication