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Information hiding is a crucial technology in the field of information security. Embedding capacity and stego-image quality are two key performance metrics in information hiding. In recent years, many information-hiding methods have been proposed to enhance embedding capacity and stego-image quality. However, through the study of these methods, we found that there is still room for improvement in terms of performance. This paper proposes a high-capacity information-hiding method based on a chunking matrix (CM). CM divides a 256×256 matrix into blocks, where each block contains k×k corresponding secret numbers. A pair of pixels is extracted from the original image and used as the coordinates for the matrix. In the search domain at that coordinate position, the corresponding secret number is found, and the matrix coordinates of the secret information are used as the pixel value for the stego-image. This paper evaluates the security and effectiveness of CM through measures such as embedding capacity, peak signal-to-noise ratio (PSNR), and bit-plane analysis. CM achieves a maximum embedding capacity of 4.806 bits per pixel (bpp) and maintains a PSNR value of more than 30 dB. Furthermore, the bit-plane analysis fails to detect the presence of the information hidden using CM method. [ABSTRACT FROM AUTHOR]

In this paper, we focus on Brauer's height zero conjecture, Robinson's conjecture, and Olsson's conjecture regarding the direct product of finite groups and give relative versions of these conjectures by restricting them to the algebraic concept of the anchor group of an irreducible character. Consider G to be a finite simple group. We prove that the anchor group of the irreducible character of G with degree p is the trivial group, where p is an odd prime. Additionally, we introduce the relative version of the Green correspondence theorem with respect to this group. We then apply the relative versions of these conjectures to suitable examples of simple groups. Classical and standard theories on the direct product of finite groups, block theory, and character theory are used to achieve these results. [ABSTRACT FROM AUTHOR]

We consider G to be a finite group and p as a prime number. We fix ψ to be an irreducible character of G with its restriction to all p-regular elements of G and ψ 0 to be an irreducible Brauer character. The main aim of this paper is to describe and investigate the relationship between cyclic anchor group of ψ and the defect group of a p-block which contains ψ. Our methods are to study and generalize some facts for the cyclic defect groups of a p-block B to the case of a cyclic anchor group of irreducible characters which belong to B. We establish and prove a criteria for an irreducible character to have a cyclic anchor group. [ABSTRACT FROM AUTHOR]

In this paper, we introduce codes equipped with pomset block metric. A Singleton type bound for pomset block codes is obtained. Code achieving the Singleton bound, called a maximum distance separable code (for short, MDS ( P , π )-code) is also investigated. We extend the concept of I-perfect codes and r-perfect codes to pomset block metric. The relation between I-perfect codes and MDS (P , π) -codes is also considered. When all blocks have the same dimension, we prove the duality theorem for codes and study the weight distribution of MDS pomset block codes when the pomset is a chain. [ABSTRACT FROM AUTHOR]

Online spaces provide opportunities for creating ties with other people, allowing us to communicate and share content with them. Sometimes, though, we wish to break some of these ties; we wish not only to friend and to follow, but to unfriend and unfollow as well. In this paper, we present a history of the many features for online interpersonal disconnectivity, showing how they have developed over time. We present five main findings: the language of tie breaking is consistently bureaucratic; over time, the features for tie breaking tend to operate on the feed rather than on social ties themselves; platforms are more reactive than proactive when it comes to tie breaking features; new ways for preventing interactions are launched over time; and the features for tie breaking sometimes create what we call "impossible social situations." This approach shines a spotlight on a neglected aspect of social media, and opens up new ways of thinking about how the platforms conceive of–and construct–online sociability. [ABSTRACT FROM AUTHOR]

Congenitally corrected transposition of the great arteries (ccTGA) is a rare congenital anomaly defined by double discordance – atrioventricular and ventricular-arterial. ccTGA frequently has associated lesions, which influence long-term survival. The management of patients with ccTGA regarding the closure of defects and pacing strategies is often very challenging. Moreover, tricuspid valve regurgitation and its impact on the systemic right ventricle requires close monitoring and potentially timely interventions. In this paper, we present and discuss the management challenges raised by a patient with situs inversus totalis, dextrocardia, ccTGA, Ebstein anomaly of the tricuspid valve, atrial septal defect, and complete atrioventricular block. [ABSTRACT FROM AUTHOR]

This paper mainly contributes a bit-level and pixel-level double-permutation image encryption scheme based on DNA coding technology, which can effectively solve the problem that adjacent pixels in an image are difficult to be completely disordered. Firstly, the Hamming distance between image pixel and a value at the same position in a chaotic sequence is calculated and the result is used to be the cyclic shift distance of the pixel to achieve bit-level permutation; secondly, the modified Z curve is used for the first global permutation process, and the image is further permutated by the method of block restructuring to compensate for the shortage of modified Z curve permutation; thirdly, pixel pairs are selected and the pixel pairs are used as information and control positions respectively to DNA encode the image by dynamically selecting the DNA encoding rules, and then diffusing the encoded image following the rules of DNA base manipulation; finally, the diffused image is decoded to complete the image encryption process. We perform simulation experiments on the image encryption algorithm and analyze its security performance, and we could get the conclusion that the encryption algorithm can encrypt images quickly and effectively, the obtained cipher images are highly resistant to noise attacks, cropping attacks, and different attacks, meanwhile, the cipher images have a lower correlation between pixels. [ABSTRACT FROM AUTHOR]

Let G be a vertex-colored graph. A vertex cut S of G is called a monochromatic vertex cut if the vertices of S are colored with the same color. A graph G is monochromatically vertex-disconnected if any two nonadjacent vertices of G have a monochromatic vertex cut separating them. The monochromatic vertex disconnection number of G , denoted by m v d (G) , is the maximum number of colors that are used to make G monochromatically vertex-disconnected. In this paper, the connection between the graph parameters are studied: m v d (G) , connectivity and block decomposition. We determine the value of m v d (G) for some well-known graphs, and then characterize G when n − 5 ≤ m v d (G) ≤ n and all blocks of G are minimally 2-connected triangle-free graphs. We obtain the maximum size of a graph G with m v d (G) = k for any k. Finally, we study the Erdős-Gallai-type results for m v d (G) , and completely solve them. [ABSTRACT FROM AUTHOR]

As the feature size of integrated circuit decreases, semiconductor devices become more susceptible to Single-Event-Upset (SEU) effect. This paper proposes a radiation hardened latch for Triple-Node-Upset (TNU) tolerance, which can block any triple node upset. Compared with previous radiation hardened TNU Tolerant (TNUT) latches, the proposed Low power-consumption TNUT (LTNUT) latch has the lowest power consumption. When compared with TNU Hardened Latch (TNUHL), TNUT Latch, TNU Completely Tolerant latch (TNUCT), Single-event Multiple-Node Upset Tolerant latch (SMNUT), TNU self-Recoverable Latch (TNURL), Low Cost and TNU-self-Recoverable Latch (LCTNURL) and Quadruple Dual Interlocked Storage Cell (Quadruple-DICE), the proposed LTNUT latch achieves reduction in power consumption by 30.77%, 17.11%, 40%, 20.25%, 20.25%, 27.59% and 64%, respectively. The proposed LTNUT latch achieves reduction in delay by 94.98%, 98.33%, 54.19%, 70.63% and 66.59% when compared with TNUHL, TNUT Latch, SMNUT, TNURL, LCTNURL, respectively, and introduces rise in delay by 3.38% and 5.52%, respectively, when compared with TNUCT and Quadruple-DICE. The proposed LTNUT latch has the lowest power consumption and second smallest delay. The proposed latch is not severely sensitive to temperature and voltage variations. [ABSTRACT FROM AUTHOR]

Let G = (V (G), E(G)) be a simple undirected graph. A block of G is a maximal connected subgraph of G that contains no cut-vertices [11]. The family of vertex sets of blocks of G generates a unique topology. In this paper, we formally define the topology generated by the family of blocks in a graph called the block topological space. Moreover, we characterize and describe some special attributes of the block topological space. Finally, we associate a corresponding graph from a given block topological space by defining the block topological graph. [ABSTRACT FROM AUTHOR]

In this paper we follow a hypothetical mathematician who is working on a problem that is eventually solved. We treat this problem as if it were difficult for the mathematician. In following the mathematician's work, we note both what she does and what she doesn't do in the process. By the latter, we consider the times when progress is not being made and how this lack of progress is resolved. The purpose here is to give some idea of how a research mathematician might approach a research level problem. We also propose that the problem under discussion is one of many problems that tertiary students can valuably tackle using a discovery-based approach as a means of using their mathematical content knowledge as well as learning to be creative. [ABSTRACT FROM AUTHOR]

This paper describes high-frequency nerve block experiments carried out on rat sciatic nerves to measure the speed of recovery of A fibres from block carryover. Block carryover is the process by which nerve excitability remains suppressed temporarily after High Frequency Alternative (HFAC) block is turned off following its application. In this series of experiments 5 rat sciatic nerves were extracted and prepared for ex-vivo stimulation and recording in a specially designed perfusion chamber. For each nerve repeated HFAC block and concurrent stimulation trials were carried out to observe block carryover after signal shutoff. The nerve was allowed to recover fully between each trial. Time to recovery from block was measured by monitoring for when relative nerve activity returned to within 90% of baseline levels measured at the start of each trial. HFAC block carryover duration was found to be dependent on accumulated dose by statistical test for two different HFAC durations. The carryover property of HFAC block on A fibres could enable selective stimulation of autonomic nerve fibres such as C fibres for the duration of carryover. Block carryover is particularly relevant to potential chronic clinical applications of block as it reduces power requirements for stimulation to provide the blocking effect. This work characterizes this process toward the creation of a model describing its behavior. [ABSTRACT FROM AUTHOR]

Flexible surface treatment for exterior pavement applications and the particular requirement to be specific pedestrian walkway design and parking areas are the fundamental feature of paver block identification. The use of conventional materials such as cement, aggregate, and sand is no longer such a priority. Under those circumstances, the production of research-based pavers block has been done to ensure the sustainability and usability of new building materials is expanded. Henceforth, this research is conducted to study and investigate the potential of using waste materials as a partial substitute for aggregate in producing concrete paving block (CPB). In essence, the application of waste materials in concrete paver blocks is highly potential. The innovations in recycling technologies expanded the usage of waste materials to produce paver block products. On the whole, in the manufacturing of concrete, the paper improves and enhances the usability of waste materials. The application of various waste materials such as plastic, steel slag, and crumb rubber is excellent. Compressive strength of paver blocks with different rates of waste steel aggregates and utilizing elastic cushions shows paver blocks give up to 50% more strength quality than customary paver blocks. In terms of the use of industrial waste materials, as a substitute material by reducing the percentage amount of the weight of the cement with the composition ratio varies based on the comparative volume category of the paving block aggregate such as 0%, 5%, 10%, 15%, 20%, and 25% are more applicable. [ABSTRACT FROM AUTHOR]

The concept of a tolerance relation, shortly called tolerance, was studied on various algebras since the seventies of the twentieth century by B. Zelinka and the first author (see e.g. [6] and the monograph [1] and the references therein). Since tolerances need not be transitive, their blocks may overlap and hence in general the set of all blocks of a tolerance cannot be converted into a quotient algebra in the same way as in the case of congruences. However, G. Czédli ([7]) showed that lattices can be factorized by means of tolerances in a natural way, and J. Grygiel and S. Radeleczki ([8]) proved some variant of an Isomorphism Theorem for tolerances on lattices. The aim of the present paper is to extend the concept of a tolerance on a lattice to posets in such a way that results similar to those obtained for tolerances on lattices can be derived. [ABSTRACT FROM AUTHOR]

An adaptive force model is proposed to achieve better performance between the accuracy and the speed of cloth simulation in three-dimensional (3D) space. The proposed force model can be expressed with a general mathematical form demonstrated by the distance between the clothing and the human body. This paper defines how a continuous adaptive area can be established with a shape "block". It is clarified that, within a specific block, a force model is expressed with the gravity of the clothing, the forces of the adjacent blocks and the anti-force of the human body to the block. In this manner, the force model of the desired clothing can be obtained through a general mathematical expression. The simulations and experimental results demonstrate that the acceptable clothing simulation in 3D space can be achieved with higher speed by saving about 20.2% runtime, and the efficiency of the proposed scheme can be verified. [ABSTRACT FROM AUTHOR]

Peter Cameron introduced the concept of the circular altitude of graphs, a parameter which was shown by Bamberg et al. that provides a lower bound on the circular chromatic number. In this paper, we investigate this parameter and show that the circular altitude of a graph is equal to the maximum of circular altitudes of its blocks. Also, we show that homomorphically equivalent graphs have the same circular altitudes. Finally, we prove that the circular altitude of the Cartesian product of two graphs is equal to the maximum of circular altitudes of its factors. [ABSTRACT FROM AUTHOR]

Summary: Past earthquakes had shown vulnerability of infill walls especially under out of plane (OOP) loading. Although some new infill walls show a good OOP performance, generally, they do not have the right economic justification or have complexity in construction. Therefore, in this paper, an innovative economical infill wall is presented that is not complicated in construction. The proposed wall constructed by light expanded clay aggregate in especial shape that reinforced with side plates, top, and bottom rebars. Experimental and numerical studies were carried out to investigate its seismic performance. Experimental results showed a high continuity between blocks of wall due to its especial shape that is increased ultimate OOP strength and ultimate OOP displacement of the wall. Numerical results indicated, because the infill wall is isolated from boundary frame, no drift is imposed to infill wall from boundary frame. Therefore, the infill wall only suffered OOP seismic acceleration. Due to light weight of the infill wall, low OOP load that corresponds to seismic acceleration is applied to the infill wall. In the infill wall, no separation is made even up to drift frame of 2.5%. The relations to design of the proposed infill wall were also presented. [ABSTRACT FROM AUTHOR]

The goal of spatio-temporal data mining is to discover previously unknown but useful patterns from the spatial and temporal data. However, explosive growth of the spatiotemporal data emphasizes the need for developing novel computationally efficient methods for large-scale data mining applications. Since lots of spatiotemporal data mining problems can be converted to an optimization problem, in this paper, we propose an efficient parameter-level parallel optimization algorithm for large-scale spatiotemporal data mining. In detail, most of previous optimization methods are based on gradient descent methods, which iteratively update the model and provide model-level convergence control for all parameters. Namely, they treat all parameters equally and keep updating all parameters until every parameter has converged. However, we find that during the iterative process, the convergence rates of model parameters are different from each other. This may cause redundant computation and reduce the performance. To solve this problem, we propose a parameter-level stochastic gradient descent (plpSGD), in which the convergence of each parameter is considered independently and only unconvergent parameters are updated in each iteration. Moreover, the updating of model parameters are parallelized in plpSGD to further improve the performance of SGD. We have conducted extensive experiments to evaluate the performance of plpSGD. The experimental results show that compared to previous SGD methods, plpSGD can significantly accelerate the convergence of SGD and achieve the excellent scalability with little sacrifice of the solution accuracy. [ABSTRACT FROM AUTHOR]

We study a block B of a finite group with respect to an algebraically closed field of prime characteristic through the Loewy length llZB of the center ZB. In this paper, we give some upper bounds for llZB in terms of characters, subsections and defect groups associated to B. As a corollary to these results, we characterize some blocks by llZB. [ABSTRACT FROM AUTHOR]

Smartphone sensors are widely used in the development of fitness, running, workout, or health applications (apps). However, smartphone sensors may increase the risk of privacy leakage when they bring convenience to users. Traditional access control mechanisms, such as Android Permission, cannot prevent authorized malicious apps from abusing sensor resources. In this paper, a novel behavior-based sensor access control scheme is presented. This scheme can further regulate the behavior of an app after it is authorized, so that it can only access sensor resources with secure behavior patterns (SBPs), and sensor-based privacy leakage may thereby be blocked. On the basis of user interface (UI) operation tracking and tagging, this scheme implements the dynamic perception of app sensor access behaviors. With a temporal logic known as temporal logic of causal knowledge (TLCK), we developed a method to construct the secure sensor access behavior pattern. Every sensor may be given a SBP. By comparing the dynamic sensor access behavior of an app with SBP, we can determine if the sensor access is secure. Moreover, by supervising the call stack of the app's sensor access application programming interface (API), we may timely block a sensor access when it is not secure. In this report, we also describe the implementation of a prototype defense system to analyze the effectiveness and efficiency of the scheme. The experimental results show that this scheme can effectively block the abnormal sensor access of an app with a performance overhead of about 10%. [ABSTRACT FROM AUTHOR]

Let B n , q be the set of all block graphs with n vertices and all blocks on q + 1 vertices for every q ≥ 2. In this paper, we determine the unique graph in B n , q that attains the minimum spectral radius. This solves a conjecture posted by Conde et al. (2022) [4]. [ABSTRACT FROM AUTHOR]

Aiming at the Jurassic continental sandstone reservoir in the west of Ordos Basin, this paper studies the petrology, pore structure and physical properties of reservoir rocks by using micro experimental test methods such as XRD whole rock mineral test, rock slice and SEM scanning. The diagenesis of reservoir rocks is analyzed, and a set of standards for the block is established for the reservoir classification. The results show that the Jurassic continental sandstone in the area is dominated by lithic feldspar sandstone, and the interstitial materials are mainly feldspar, siliceous and clay minerals with a content of 17.02%. The pores are mainly intergranular pores. In diagenesis, compaction and cementation have the most obvious effects on rock porosity, and greatly reduce the pore space of tight sandstone. However, dissolution can improve the porosity of tight sandstone, and the effect of metasomatism can be ignored. In addition, based on the reservoir classification criteria established by sedimentary environment and microscopic characteristics, the study area is divided into three types of reservoirs, and the spatial distribution of various types of reservoirs is evaluated. [ABSTRACT FROM AUTHOR]

Researches in green building materials consist of developing alternatives to traditional materials or processes that offer environmental advantages. This paper presents an experimental investigation performed on new green and ecological blocks based on gypsum plaster and desert sand mortar. The first part of this experimental investigation focuses on the incorporation of desert sand, with different proportions, in the plaster matrix. For this, different cubic and cylindrical specimens were prepared by adding 0, 20, 30, 40, 50, 60, 70 or 80% sand to the mixture. Thereafter, physical and mechanical properties of mixtures, such as density, absorption, hydration temperature, and compressive strength, were investigated. The results showed that the incorporation of desert sand has significantly improved the properties of sand–plaster mortar compared to those of plaster mortar. The second part of this study consists of studying new ecological blocks manufactured from the optimal mixture, 50% sand + 50% plaster. The results carried out on prototypes of the new blocks give to this new block the opportunity to be used as insulated building materials for the construction of interior walls. [ABSTRACT FROM AUTHOR]

This paper addresses the two-dimensional strip-packing (2DSP) problem of placing a set of rectangular pieces onto a fixed-width rectangular sheet to minimize the total length used. We propose a Block-Based Heuristic Search Algorithm (BBHSA) to solve 2DSP problems with guillotine cut constraints. Initially, it converts the 2DSP problem into a series of 2D rectangular packing problems (2DRP), where the size of the sheet is fixed. In the BBHSA, rectangular pieces are aggregated into blocks, which are partial solutions without residual space. These blocks provide the ingredients for a good layout and are basic components in a tree-based constructive search process. Two basic operations, called placing & splitting and approximate binary search are used in the search process. Furthermore, several block-based placement rules are explored to speed up the search process and improve solution quality. To verify the performance of our proposed algorithm, we conducted extensive experiments using the zero-waste benchmark and non-zero-waste benchmark instances. The results show that BBHSA demonstrates computational effectiveness, particularly in zero-waste cases, achieving optimal solutions for almost all zero-waste benchmark instances reported in the existing literature. [ABSTRACT FROM AUTHOR]

Multistep integration methods are being extensively used in the simulations of high dimensional systems due to their lower computational cost. The block methods were developed with the intent of obtaining numerical results on numerous points at a time and improving computational efficiency. Hybrid block methods for instance are specifically used in numerical integration of initial value problems. In this paper, an optimized hybrid block Adams block method is designed for the solutions of linear and nonlinear first-order initial value problems in ordinary differential equations (ODEs). In deriving themethod, the Lagrange interpolation polynomial was employed based on some data points to replace the differential equation function and it was integrated over a specified interval. Furthermore, the convergence properties along with the region of stability of the method were examined. It was concluded that the newly derived method is convergent, consistent, and zero-stable. The method was also found to be A-stable implying that it covers the whole of the left/negative half plane. From the numerical computations of absolute errors carried out using the newly derived method, it was found that the method performed better than the ones with which we compared our results with. Themethod also showed its superiority over the existing methods in terms of stability and convergence. [ABSTRACT FROM AUTHOR]

In this paper we analyze the length-spectrum of blocks in γ -structures. γ -structures are a class of RNA pseudoknot structures that play a key role in the context of polynomial time RNA folding. A γ -structure is constructed by nesting and concatenating specific building components having topological genus at most γ . A block is a substructure enclosed by crossing maximal arcs with respect to the partial order induced by nesting. We show that, in uniformly generated γ -structures, there is a significant gap in this length-spectrum, i.e., there asymptotically almost surely exists a unique longest block of length at least n - O (n 1 / 2) and that with high probability any other block has finite length. For fixed γ , we prove that the length of the complement of the longest block converges to a discrete limit law, and that the distribution of short blocks of given length tends to a negative binomial distribution in the limit of long sequences. We refine this analysis to the length spectrum of blocks of specific pseudoknot types, such as H-type and kissing hairpins. Our results generalize the rainbow spectrum on secondary structures by the first and third authors and are being put into context with the structural prediction of long non-coding RNAs. [ABSTRACT FROM AUTHOR]

This paper presents an effective lip pixel detection method based on blocks and deep neural networks. Since only-rough localization of a pair of lips is a trivial task, we use a rectangle that loosely bounds two lips as an input region of interest for lip detection. For each pixel in the rectangle region we generate a block whose center is at the pixel, and the pixel is classified into either a lip or non-lip pixel by exploiting the pixels in the block. Deep neural networks are trained using a sufficient number of labeled blocks obtained from a quite tractable number of labeled images. As a result, lip pixels are detected with high accuracy despite negligible labeling effort. Experimental results demonstrate the effectiveness of the presented method. We show that even single-minute training can outperform the mouth map with the best threshold. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper was to evaluate our institutional experience with regional anesthetic and whether this is a modality worth continuing to pursue given its associated risks. Methods: This is a single institution, retrospective review of 1 surgeon's case volume over the course of January 2015 to December 2016. Patients' charts were reviewed and selected based on dialysis access with regional anesthesia and adequate intraoperative/postoperative information to warrant inclusion. Other modalities for anesthesia were included. Primary outcomes included: functional patency at 6 months, whether the most distal access was obtained at the time of the operation based on preoperative planning, and whether there was a change in operative plans based on preoperative imaging. Results: Overall, 164 charts were reviewed, with 45 patients included in this study. Thirty-three patients had regional anesthesia, 10 had local, and 2 underwent general anesthesia. The results showed that, in comparing regional and local anesthesia, there was a clear statistical benefit in achieving the most distal configuration based on planned preoperative assessment (P = 0.03). There was no clear advantage in terms of functional patency at 6 months. When comparing the changes in planned access based on the use of intraoperative ultrasound, there was a moderately acceptable effect on functional patency (P = 0.08). Conclusion: Regional anesthesia does appear to have certain early technical benefits due to venodilatation. It may also lend the surgeon to develop more autogenous fistulas on the day of the operation avoiding graft placement or, at minimum, develop the most distal configuration possible. However, given the small sample size and single institution evaluation, these conclusions are incomplete until further prospective studies can be conducted. [ABSTRACT FROM AUTHOR]

In multi-hop wireless networks, minimizing the transmission time is very important. In this paper, a high-reliability relay algorithm (HRRA) is proposed to decrease the transmission time based on the network coding in multi-rate environment. The HRRA includes the relay selection algorithm (RSA) and the block transmission algorithm (BTA). Based on the relay reliability of node, RSA chooses the neighbor with the higher link rate as the common relay node and creates more network coding opportunities at the common relay node. Thus, the network coding opportunities and the high-rate links associated with common node could both be exploited in the transmissions of BTA. Moreover, a comprehensive theoretical analysis of the transmission time of HRRA in a block is presented. Lastly, the simulation results show that HRRA can significantly reduce the transmission time compared with the shortest path algorithm and heuristic relay node selection algorithm and COPE. [ABSTRACT FROM AUTHOR]

In building stones, discontinuities, non-uniformity, and irregular shape are among the problems that reduce the quality of products. Stone blocks, slabs, and tiles are the main products of quarries and stone processing plants. Quantifying the quality is a key factor in valuation of these products. This paper proposes a quality factor formula to determine the quality of stone blocks (three-dimensional) and products from stone processing plants (two-dimensional). This factor, which shows the uniformity and esthetic index of a piece of stone, is determined based on the shape quality (α), number, size, and esthetic quality (β) of the pieces and the discontinuity factor (γ) that separates the pieces. The quality factor is defined in a way that each previously mentioned characteristic of a piece is involved in the quality factor formula calculation. The quality factor ranges between 0 and 1 and can be expressed as a percentage. The proposed quality factor was calculated for a number of different stone blocks, slabs, and tiles to examine the validity of the quality factor formula. The results showed that the shape quality is the most significant parameter in determining the quality of stone blocks in quarries. Moreover, in processing plant products the esthetic quality and the number of stone pieces in a product are the key factors for determination of their quality. The discontinuity factor is a parameter that reduces the quality of stone products significantly. Furthermore, the quality factor formula can be used as a convenient tool for classifying the products of quarries and stone processing plants. [ABSTRACT FROM AUTHOR]

Bitcoin is a digital cryptocurrency that has attracted substantial interest in recent years from the general public, profit seekers, risk takers, academic practitioners, and, last but not least, economists. Although it is referred to as new, Bitcoin has existed since 2009 and is rooted in technology that goes back even farther. It was the first established cryptocurrency, with the first trade in 2010. Since 2015, Bitcoin has attracted even more attention because of its increase in value and volume of exchange. The Bitcoin system maintains a global, distributed cryptographic ledger of transactions, or blockchain, through a consensus algorithm running on hardware scattered around the world. This paper discusses the nature of cryptocurrency and blockchain, how it works, and the present status of Bitcoin blockchain in different countries around the world. The paper also includes a review of literature on Bitcoin engineering, Bitcoin as currency and the cryptocurrency system, related work on queuing theory, and work on competition and monopoly. The paper explores three possible outcomes with regard to the future prospects of Bitcoin. The various aspects of this technology are yet to be revealed in detail, but the authors hope that this simple, basic, and narrative paper will be helpful to those seeking basic references regarding this newest issue. [ABSTRACT FROM AUTHOR]

The UV irradiation method provides us a new way of preparing resorcinol-formaldehyde (RF) aerogel. In this paper, water soluble, neutral photo-initiator 659 was used to synthesize RF aerogel by using free radical UV initiator. Incorporation of the UV initiators during the sol-gel stage usually decreases the gel-time. On changing the performed time and initiators quantities in synthesizing RF aerogel, The results will be discussed that gel-time of the RF aerogel definitely depends on the polymerization time and initiators quantities. The paper will also be discussed the RF aerogel developed for UV irradiation method and Sol-gel method by IR spectrum, Scanning electron microscopy, N adsorption/desorption to show that light initiator does not play any role in the formation of the aerogel skeleton; The RF aerogel using UV irradiation method still maintain a high pore structure, shorter gel-time and the three-dimensional size block. [ABSTRACT FROM AUTHOR]

The spectral moments of ensembles of sparse random block matrices are analytically evaluated in the limit of large order. The structure of the sparse matrix corresponds to the Erdösâ€"Renyi random graph. The blocks are i.i.d. random matrices of the classical ensembles GOE or GUE. The moments are evaluated for finite or infinite dimension of the blocks. The correspondences between sets of closed walks on trees and classes of irreducible partitions studied in free probability together with functional relations are powerful tools for analytic evaluation of the limiting moments. They are helpful to identify probability laws for the blocks and limits of the parameters which allow the evaluation of all the spectral moments and of the spectral density. [ABSTRACT FROM AUTHOR]

Abstract The lesser occipital nerve (LON) has one of the most variations among occipital nerves. We aimed to investigate morphological and morphometric features of LON. A total of 24 cadavers, 14 males (58%) and 10 females (42%), were dissected bilaterally. LON was classified into 3 types. The number of branches and the perpendicular distances of the point where LON emerged from the posterior border of sternocleidomastoid muscle to vertical and transverse lines passing through external occipital protuberance were determined. The shortest distance between LON and great auricular nerve (GAN), and linear distance of LON to its branching point were measured. The most common variant was Type 1 (30 sides, 62.5%), followed by Type 2 (12 sides, 25%) and Type 3 (6 sides, 12.5%), respectively. In males, Type 1 (22 sides, 78.6%) was the most common, while Type 1 (8 sides, 40%) and Type 2 (8 sides, 40%) were equally common and the most common in females. On 48 sides, 2–9 branches of LON were observed. The perpendicular distance of said point to vertical and transverse lines was meanly 63.69 ± 11.28 mm and 78.83 ± 17.21 mm, respectively. The shortest distance between LON and GAN was meanly 16.62 ± 10.59 mm. The linear distance of LON to its branching point was meanly 31.24 ± 15.95 mm. The findings reported in this paper may help clinicians in estimating the location of the nerve and/or its branches for block or decompression surgery as well as preservation of LON during related procedures.

Edges of a fuzzy graph are mainly classified into α, β and δ. In this paper, we study certain saturation counts with respect to the classification of edges. Characterizations for fuzzy cycles, fuzzy trees, blocks in fuzzy graphs and complete fuzzy graphs are also obtained using saturation counts. [ABSTRACT FROM AUTHOR]