IoTranx: Transactions for Safer Smart Spaces

Smart spaces such as smart homes deliver digital services to optimize space use and enhance user experience. They are composed of an Internet of Things (IoT), people, and physical content. They differ from traditional computer systems in that their cyber-physical nature ties intimately with the users and the built environment. The impact of ill-programmed applications in such spaces goes beyond loss of data or a computer crash, risking potentially physical harm to the space and its users. Ensuring smart space safety is therefore critically important to successfully deliver intimate and convenient services surrounding our daily lives. By modeling smart space as a highly dynamic database, we present IoT Transactions, an analogy to database transactions, as an abstraction for programming and executing the services as the handling of the devices in smart space. Unlike traditional database management systems that take a “clear room approach,” smart spaces take a “dirty room approach” where imperfection and unattainability of full control and guarantees are the new normal. We identify Atomicity, Isolation, Integrity and Durability (AI 2 D) as the set of properties necessary to define the safe runtime behavior for IoT transactions for maintaining “permissible device settings” of execution and to avoid or detect and resolve “impermissible settings.” Furthermore, we introduce a lock protocol, utilizing variations of lock concepts, that enforces AI 2 D safety properties during transaction processing. We show a brief proof of the protocol correctness and a detailed analytical model to evaluate its performance.

An experiment design for schools to demonstrate the Maxwell distribution

The article describes a new version of a demonstration experiment for the Maxwell distribution. In the first part students analyse the applicability of the Gaussian distribution to the projection of the particle velocities in the suggested experiment. Further, students observe two-dimensional distribution of particles by the modulus of velocity in a mechanical demonstration model and compare the results with theoretical provisions. Demonstration of the two-dimensional version of the Maxwell distribution for particle interaction allows students to independently derive formulas for the three-dimensional Maxwell distribution for particles in an ideal gas. The use of the suggested demonstration ensures active engagement in fundamentally important physical content.

Ostrogradsky–Hamilton approach to geodetic brane gravity

In this paper, we develop the Ostrogradsky–Hamilton formalism for geodetic brane gravity, described by the Regge–Teitelboim geometric model in higher codimension. We treat this gravity theory as a second-order derivative theory, based on the extrinsic geometric structure of the model. As opposed to previous treatments of geodetic brane gravity, our Lagrangian is linearly dependent on second-order time derivatives of the field variables, the embedding functions. The difference resides in a boundary term in the action, usually discarded. Certainly, this suggests applying an appropriate Ostrogradsky–Hamiltonian approach to this type of theories. The price to pay for this choice is the appearance of second-class constraints. We determine the full set of phase space constraints, as well as the gauge transformations they generate in the reduced phase space. Additionally, we compute the algebra of constraints and explain its physical content. In the same spirit, we deduce the counting of the physical degrees of freedom. We comment briefly on the naive formal canonical quantization emerging from our development.

Characteristics of Liquid Smoke of Red Fruit (Pandanus conoideus. L.) Waste with Pyrolysis Method and Potentially as Biopesticide

This study aims to determine the yield and quality of liquid smoke in the form of pH values, acid levels, and phenol levels from the burning of red fruit seed waste as raw material for grade 3 liquid smoke using pyrolysis equipment. Liquid smoke is used as an alternative food preservative and flavor enhancer that it can use in the food processing industry to minimize the use of harmful preservatives such as formalin. But it also can be used as a biopesticide in agriculture so that it becomes an alternative to chemical pesticides in controlling pests. It was researched at the Research Laboratory of the Chemical Engineering Department FTI UMI Makassar in July 2020 and the Agrotechnology Laboratory of the Petra Baliem Wamena Agricultural Science College in April 2021. The research activity began by making grade 3 liquid smoke because liquid smoke can be used as a biopesticide at this level. Then proceed with the analysis of the chemical and physical content of liquid smoke. The research method used was an experimental method with six replications on the amount of red fruit seed waste 500 g, 1000 g, and 1500 g. The pyrolysis process was carried out at temperatures ranging from 300-400ºC for 180 minutes. The results of the observations from the tests carried out showed that the liquid smoke of red fruit seed waste produced was more in the weight or quantity of red fruit seed waste 1000 g was BM2 treatment which had a pH value of 3.35, the acid content of 14.20%, total phenol content of 4.91%, quite brown. Thick and smells like liquid smoke. The high levels of acid ranging from 13.73-14.20% and high levels of phenol ranging from 4.91-5.11% compared to previous studies with raw materials for liquid smoke of rice husks, coconut shells, and organic waste, made the liquid smoke of red fruit seed waste as a biopesticide with repellant and anti-inflammatory properties. Insects ate them because acids and phenols can provide an aromatic that insects do not like.

Elements of the Metric–Affine gravity I: Aspects of F(R) theories reductions and the topologically massive gravity

Some classical aspects of Metric–Affine Gravity are reviewed in the context of the [Formula: see text] type models (polynomials of degree [Formula: see text] in the Riemann tensor) and the topologically massive gravity. At the nonperturbative level, we explore the consistency of the field equations when the [Formula: see text] models are reduced to a Riemann–Christoffel (RCh) space–time, either via a Riemann–Cartan (RC) space or via an Einstein–Weyl (EW) space. It is well known for the case [Formula: see text] that any path or reduction “classes” via RC or EW leads to the same field equations with the exception of the [Formula: see text] theories for [Formula: see text]. We verify that this discrepancy can be solved by imposing nonmetricity and torsion constraints. In particular, we explore the case [Formula: see text] for the interest in expected physical solutions as those of conformally flat class. On the other hand, the symmetries of the topologically massive gravity are reviewed, as the physical content in RC and EW scenarios. The appearance of a nonlinearly modified selfdual model in RC and existence of many nonunitary degrees of freedom in EW with the suggestion of a modified model for a massive gravity which cure the unphysical propagations shall be discussed.

Developing orbital-free quantum crystallography: the local potentials and associated partial charge densities

This work extends the orbital-free density functional theory to the field of quantum crystallography. The total electronic energy is decomposed into electrostatic, exchange, Weizsacker and Pauli components on the basis of physically grounded arguments. Then, the one-electron Euler equation is re-written through corresponding potentials, which have clear physical and chemical meaning. Partial electron densities related with these potentials by the Poisson equation are also defined. All these functions were analyzed from viewpoint of their physical content and limits of applicability. Then, they were expressed in terms of experimental electron density and its derivatives using the orbital-free density functional theory approximations, and applied to the study of chemical bonding in a heteromolecular crystal of ammonium hydrooxalate oxalic acid dihydrate. It is demonstrated that this approach allows the electron density to be decomposed into physically meaningful components associated with electrostatics, exchange, and spin-independent wave properties of electrons or with their combinations in a crystal. Therefore, the bonding information about a crystal that was previously unavailable for X-ray diffraction analysis can be now obtained.

PHYSICAL CONTENT OF COMPUTER STEGANOGRAPHY

Introduction. The development of computer technology has given a new impetus to the use of computer steganography. However, it is important to understand the physical content of this type of steganography.Purpose. The work aims to describe the practical use and physical content of the phenomenon of computer steganography, the results of the study on the hiding of files in the stegocontainer.Results. Describes the main ns currently computer steganography methods are actively used to solve the following tasks: Protection of confidential information from unauthorized access, overcoming monitoring and management of net-work resources, software camouflage, copyright protection, which is manifested in the use of digital watermarks, is one of the most promising areas of computer steganography. Among the methods of hiding information in images, the most common is the category of algorithms using the lower bits of the image data. They are considered in this paper. These algorithms are based on the fact that in some file formats, the lower bits of the values, although present in the file, but do not affect a person's perception of sound or image. The steganographic software S-Tools was chosen for the study. We created two test monotonous images with the size of 50 × 50 pixels in 24-bit bmp format to analyze the peculiarities of the placement of stego-data in container files. We chose black and white images for the study. A text file was hidden in each of the images, after which the reverse action was performed - extracting the file. As a result of hiding, two stego files were obtained. The paper compared the binary content of the original images and files containing private data. For comparison, the binary content of the black square image and the contents of the stegocontainer with a latent text file are given. Note that the contents of the container and the stego file are only partially listed, but the addresses of the memory cells have selected accordingly. The right column shows the contents of the memory cells in hexadecimal format. The bytes that display the colour of the square are set to "00" because the original image contains only black. We noted that the contents of the cells responsible for the image changed after hiding additional data (this reflected by cells with values of "01"). The paper also describes the procedure for hiding a group of different types of files. During the study, we found that the image file (1920 × 1080 pixels) with a volume of 6,220,854 bytes can hide 777,584 bytes of information.Conclusion. When using steganography, the program uses some algorithms that hide confidential data among the contents of the container: bits of the hidden file replace the bits of the original file at random positions. Thus, the size of the source file and the container file (containing the attached information) is the same, even if you hide a different number of files or different amounts of data.

Derivation of the stationary fluorescence spectrum formula for molecular systems from the perspective of quantum electrodynamics

Numerical simulations of stationary fluorescence spectra of molecular systems usually rely on the relation between the photon emission rate and the system’s dipole–dipole correlation function. However, research papers usually take this relation for granted, and standard textbook expositions of the theory of fluorescence spectra also tend to leave out this important relation. In order to help researchers with less theoretical training gain a deeper understanding of the emission process, we perform a step-by-step derivation of the expression for the fluorescence spectrum, focusing on rigorous mathematical treatment and the underlying physical content. Right from the start, we employ quantum description of the electromagnetic field, which provides a clear picture of emission that goes beyond the phenomenological treatment in terms of the Einstein A coefficient. Having obtained the final expression, we discuss the relation of the latter to the present level of theory by studying a simple two-level system. From the technical perspective, the present work also aims at familiarizing the reader with the density matrix formalism and with the application of the double-sided Feynman diagrams.

PPROBLEMS OF PHYSICAL CONTENT, REDUCED TO A SYSTEM OF LINEAR EQUATIONS WITH TWO VARIABLES

Functional and graphic lines are one of the foundations of mathematics teaching methods. The advantage of this line is that the study of other important lines of mathematics is carried out through the prism of the concept of function. Based on the experience of teaching mathematics, we know that the concept of function is abstract and very difficult for students to understand, so in order to enhance the visualization of the researching objects and concepts when implementing functional and graphic lines, students need to increase the system of physical content tasks for studying and understanding functions. In school course of algebra, the functional-graphical method is rarely used for solving a system of equations with two unknowns, as well as for solving equations with two unknowns. The article deals with the problems of solving problems of physical content when studying a system of linear equations with two variables in school course of algebra. The emphasis is on the fact that the considered problems with physical content are interconnected with functionalgraphic lines in algebra and allow deepening the topic, revealing the practical content. The problems with physical content presented in the article are intended for studying linear functions of algebra and their graphs, studying functions, constructing and solving equations and a system of linear equations associated with these functions.