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Objective: To characterize and validate the landscape of algorithms that use International Classification of Disease (ICD) codes to identify low‐acuity emergency department (ED) visits. Data Sources: Publicly available ED data from the National Hospital Ambulatory Medical Care Survey (NHAMCS). Study Design: We systematically searched for studies that specify algorithms consisting of ICD codes that identify preventable or low‐acuity ED visits. We classified ED visits in NHAMCS according to these algorithms and compared agreements using the Jaccard index. We then evaluated the performance of each algorithm using positive predictive value (PPV) and sensitivity, with the reference group specified using low‐acuity composite (LAC) criteria consisting of both triage and clinical components. In sensitivity analyses, we repeated our primary analysis using only triage or only clinical criteria for reference. Data Collection: We used the 2011–2017 NHAMCS data, totaling 163,576 observations before survey weighting and after dropping observations missing a primary diagnosis. We translated ICD‐9 codes (years 2011–2015) to ICD‐10 using a standard crosswalk. Principal Findings: We identified 15 papers with an original list of ICD codes used to identify preventable or low‐acuity ED presentations. These papers were published between 1992 and 2020, cited an average of 310 (SD 360) times, and included 968 (SD 1175) codes. Pairwise Jaccard similarity indices (0 = no overlap, 1 = perfect congruence) ranged from 0.01 to 0.82, with mean 0.20 (SD 0.13). When validated against the LAC reference group, the algorithms had an average PPV of 0.308 (95% CI [0.253, 0.364]) and sensitivity of 0.183 (95% CI [0.111, 0.256]). Overall, 2.1% of visits identified as low acuity by the algorithms died prehospital or in the ED, or needed surgery, critical care, or cardiac catheterization. Conclusions: Existing algorithms that identify low‐acuity ED visits lack congruence and are imperfect predictors of visit acuity. [ABSTRACT FROM AUTHOR]

Background: The idea of computational thinking is underpinned by the belief that anyone can learn and use the underlying concepts of computer science to solve everyday problems. However, most studies on the topic have investigated the development of computational thinking through programming activities, which are cognitively demanding. There is a dearth of evidence on how computational thinking augments everyday problem solving when it is decontextualized from programming. Objectives: In this study, we examined how computational thinking, when untangled from the haze of programming, is demonstrated in everyday problem solving, and investigated the features of such solvable problems. Methods: Using a multiple case study approach, we tracked how seven university students used computational thinking to solve the everyday problem of a route planning task as part of an 8‐week‐long Python programming course. Results and Conclusions: Computational thinking practices are latent in everyday problems, and intentionally structuring everyday problems is valuable for discovering the applicability of computational thinking. Decomposition and abstraction are prominent computational thinking components used to simplify everyday problem solving. Implications: It is important to strike a balance between the correctness of algorithms and simplification of the process of everyday problem solving. Lay Description: What is already known about this topic: Computational thinking is a problem solving skill.Computational thinking is different from programming.There is dearth of evidence on how computational thinking augments everyday problem solving. What this paper adds: Computational thinking practices are latent in everyday problem solving.Intentional restructuring of problems is required to uncover how computational thinking applies in solving them. Implications for practices: Decomposition and abstraction are critical in solving everyday problems.Computational thinking should be taught explicitly through everyday problems.Finding balance between the correctness of algorithm and simplification of the problem solving process is important. [ABSTRACT FROM AUTHOR]

In this paper, we focus on the link between evolution algebras and (pseudo)digraphs. We study some theoretical properties about this association and determine the properties of the (pseudo)digraphs associated with each type of evolution algebras. We also analyze the isomorphism classes for each configuration associated with these algebras providing a new method to classify them, and we compare our results with the current classifications of two‐ and three‐dimensional evolution algebras. In order to complement the theoretical study, we have designed and performed the implementation of an algorithm, which constructs and draws the (pseudo)digraph associated with a given evolution algebra and another procedure to study the solvability of a given evolution algebra. [ABSTRACT FROM AUTHOR]

Abstract: The long‐standing debate into the potential benefit of developing mathematical thinking skills through learning to program has been reignited with the widespread introduction of programming in schools across many countries, including England where it is a statutory requirement for all pupils to be taught programming from 5 years old. Algorithm is introduced early in the English computing curriculum, yet there is limited knowledge of how young pupils view this concept. This paper explores pupils' (aged 10–11) understandings of algorithm following their engagement with 1 year of ScratchMaths, a curriculum designed to develop computational and mathematical thinking skills through learning to program. A total of 181 pupils from 6 schools undertook a set of written tasks to assess their interpretations and evaluations of different algorithms that solve the same problem, with a subset of these pupils subsequently interviewed to probe their understandings in greater depth. We discuss the different approaches identified, the evaluation criteria they used, and the aspects of the concept that pupils found intuitive or challenging, such as simplification and abstraction. The paper ends with some reflections on the implications of the research, concluding with a set of recommendations for pedagogy in developing primary pupils' algorithmic thinking. [ABSTRACT FROM AUTHOR]

Summary: Wireless video sensor network (WVSN) has attracted much research interest due to its multi‐faceted potential applications in different fields. An energy‐efficient protocol is fundamental for WVSN since the network has to deal with traffic‐intensive multimedia data, such as images and videos. A few issues come in front for any such setting like energy inefficiency, throughput unfairness, and low network capacity. In many cases, we need to strike a balance between required parameters or aspects, but there is no alternative to ensuring appropriate energy efficiency in the process. Keeping this in mind, this paper proposes a holistic solution named energy‐efficient bio‐inspired Mimosa pudica (EEBIMP) algorithm. EEBIMP for WVSN can reduce the time delay and avoid unnecessary energy consumption due to clustering the network. Our proposed algorithm has been compared with one of the most recent notable solutions, like GREENNESS (Green wiReless vidEo sENsor NEtworks uSing out‐of‐band Signalling), PSO (Particle Swarm Optimization), and CUCKOO search algorithm. The result shows that EEBIMP achieved 95% of energy efficiency and throughput when compared with other algorithms of GREENNESS, PSO, and CUCKOO. [ABSTRACT FROM AUTHOR]

Rapid, accurate, and automatic quantitation of two‐dimensional nuclear magnetic resonance(2D‐NMR) data is a challenging problem. Recently, a Bayesian information criterion based subband Steiglitz–McBride algorithm has been shown to exhibit superior performance on all three fronts when applied to the quantitation of one‐dimensional NMR free induction decay data. In this paper, we demonstrate that the 2D Steiglitz–McBride algorithm, in conjunction with 2D subband decomposition and the 2D Bayesian information criterion, also achieves excellent results for 2D‐NMR data in terms of speed, accuracy, and automation—especially when compared in these respects to the previously published analysis techniques for 2D‐NMR data. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we propose an algorithm to extract threshold voltage in homojunction tunnel field effect transistors (TFETs). Single gate TFET and double gate TFET are the geometries which are considered for verification of the method. Firstly, a generalized model of surface potential based on 2D Poisson equation for homojunction TFETs is developed. Secondly, the algorithm involves a number of geometrical operations on surface potential plots, which are performed computationally. From the plots of surface potential and the geometrical constructions, a parameter, range_point, is defined through mathematical formulations. The threshold voltage is determined by subjecting the range_point to a set of constraints which are found to be same for both the devices. The validity of the algorithm is confirmed by considering different parameters like drain voltage, gate oxide thickness, and temperature for both low‐k and high‐k gate dielectric materials in TFETs. The temperature variation is validated for a heterojunction TFET too using the same generalized model of surface potential. [ABSTRACT FROM AUTHOR]

Abstract: Evidence supporting the practice of skin‐to‐skin contact and breastfeeding soon after birth points to physiologic, social, and psychological benefits for both mother and baby. The 2009 revision of Step 4 of the WHO/UNICEF “Ten Steps to Successful Breastfeeding” elaborated on the practice of skin‐to‐skin contact between the mother and her newly born baby indicating that the practice should be “immediate” and “without separation” unless documented medically justifiable reasons for delayed contact or interruption exist. While in immediate, continuous, uninterrupted skin‐to‐skin contact with mother in the first hour after birth, babies progress through 9 instinctive, complex, distinct, and observable stages including self‐attachment and suckling. However, the most recent Cochrane review of early skin‐to‐skin contact cites inconsistencies in the practice; the authors found “inadequate evidence with respect to details … such as timing of initiation and dose.” This paper introduces a novel algorithm to analyse the practice of skin to skin in the first hour using two data sets and suggests opportunities for practice improvement. The algorithm considers the mother's Robson criteria, skin‐to‐skin experience, and Widström's 9 Stages. Using data from vaginal births in Japan and caesarean births in Australia, the algorithm utilizes data in a new way to highlight challenges to best practice. The use of a tool to analyse the implementation of skin‐to‐skin care in the first hour after birth illuminates the successes, barriers, and opportunities for improvement to achieving the standard of care for babies. Future application should involve more diverse facilities and Robson's classifications. [ABSTRACT FROM AUTHOR]

Raman spectroscopy is a very powerful analytical technique with an increasing acceptance in the scientific community. For the optimization of the Raman acquisition, two main parameters, the integration time and the number of accumulations, need to be adjusted to the sample under analysis, as the sample, or even different spots on the same sample, can provide very different Raman responses one from another. In this paper, we present a suite of algorithms to automate the acquisition parameter adjustment to the sample under analysis, addressing issues such as spectral saturation, fluorescence, cosmic ray detection and removal, and adjustment of the acquisition parameters to optimize the acquired spectral data. This suite has been developed in the framework of the Raman Laser Spectrometer (RLS) instrument development for the Exomars mission but can be applied to any Raman spectrometer. This will allow the spectrometer to adapt to the characteristics of the sample that is being analyzed, optimizing the total operative time, while improving the usability and overall efficiency of the system. Copyright © 2017 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Introduction There are several papers on the sonographic features of mediastinal lymph nodes affected by several diseases, but none gives the importance and clinical utility of the features. Objective In order to find out which lymph node should be sampled in a particular nodal station during endobronchial ultrasound, we investigated the diagnostic performances of certain sonographic features and proposed an algorithmic approach. Methods We retrospectively analyzed 1051 lymph nodes and randomly assigned them into a preliminary experimental and a secondary study group. The diagnostic performances of the sonographic features (gray scale, echogeneity, shape, size, margin, presence of necrosis, presence of calcification and absence of central hilar structure) were calculated, and an algorithm for lymph node sampling was obtained with decision tree analysis in the experimental group. Later, a modified algorithm was applied to the patients in the study group to give the accuracy. Results The demographic characteristics of the patients were not statistically significant between the primary and the secondary groups. All of the features were discriminative between malignant and benign diseases. The modified algorithm sensitivity, specificity, and positive and negative predictive values and diagnostic accuracy for detecting metastatic lymph nodes were 100%, 51.2%, 50.6%, 100% and 67.5%, respectively. Conclusions In this retrospective analysis, the standardized sonographic classification system and the proposed algorithm performed well in choosing the node that should be sampled in a particular station during endobronchial ultrasound. [ABSTRACT FROM AUTHOR]

Orthogonal Latin hypercubes (OLHs) are available for only a limited collection of run sizes. This paper presents a simple algorithm for constructing orthogonal designs that are nearly Latin hypercubes. The algorithm is based on the approach developed by Steinberg and Lin for OLH designs and can generate designs for all run sizes for which a Plackett-Burman design exists. The designs have good univariate projections, although they are not perfectly uniform. They also provide good spatial coverage in higher dimensions. The great gain in sample size flexibility requires just a small sacrifice in the univariate spread of points. [ABSTRACT FROM AUTHOR]

This paper discusses the multipath allocation problem in the communication network and proposes a multipath allocation algorithm suited to the distributed environment. The multipath allocation problem is a problem where multiple paths arc to be allocated without a conflict. This problem has been difficult to solve in the distributed environment since relations among various routes must be considered. The algorithm proposed in this paper solves this point by realizing the asynchronous path search. In this paper, the basic characteristics of the proposed algorithm are described through the comparison between the proposed and the traditional algorithms for the case of serial computation under the centralized control. Then the proposed algorithm is applied to several kinds of distributed cooperative multiagent models, and it is demonstrated that the proposed model can easily be applied to the distributed environment. A simulation is executed actually using several workstations, and it is shown that the proposed algorithm is desirable as a solution method for the multipath allocation problem m the distributed environment. [ABSTRACT FROM AUTHOR]

This paper discusses the hierarchical properties of digraphs and proposes flowchart decomposition algorithms using these properties. The hierarchical structure discussed here is based on only the topological relation- skips between vertices and the inclusive relationship among sets of vertices. When the given flowchart represents the control flow of a computer program, this hierarchical structure also shows strong correspondence between these inclusive relationships and program modules. The proposed flowchart decomposition algorithm consists of one algorithm for detecting modules and another algorithm for further decomposing the detected modules. This paper focuses on the former algorithm. Because the hierarchical structure discussed in this paper corresponds to the traditional program modules (e.g., function or procedure) of most of the computer programming languages, the module-detection algorithm can be used not only for decomposing flowchart but for more general purposes, including module design. Two types of module-detection algorithm are discussed in this paper. One detects all modules, and the other detects a restricted subset of modules from the standpoint of flow-chart decomposition. We then demonstrate with a practical example that the latter algorithm is ten times faster than the former. [ABSTRACT FROM AUTHOR]

Due to historical legal challenges, there is a driving force for the development of objective methods of forensic toolmark identification. This study utilizes an algorithm to separate matching and nonmatching shear cut toolmarks created using fifty sequentially manufactured pliers. Unlike previously analyzed striated screwdriver marks, shear cut marks contain discontinuous groups of striations, posing a more difficult test of algorithm applicability. The algorithm compares correlation between optical 3D toolmark topography data, producing a Wilcoxon rank sum test statistic. Relative magnitude of this metric separates the matching and nonmatching toolmarks. Results show a high degree of statistical separation between matching and nonmatching distributions. Further separation is achieved with optimized input parameters and implementation of a 'leash' preventing a previous source of outliers-however complete statistical separation was not achieved. This paper represents further development of objective methods of toolmark identification and further validation of the assumption that toolmarks are identifiably unique. [ABSTRACT FROM AUTHOR]

SUMMARY In this paper, some important spectral characterizations of symmetric nonnegative tensors are analyzed. In particular, it is shown that a symmetric nonnegative tensor has the following properties: (i) its spectral radius is zero if and only if it is a zero tensor; (ii) it is weakly irreducible (respectively, irreducible) if and only if it has a unique positive (respectively, nonnegative) eigenvalue-eigenvector; (iii) the minimax theorem is satisfied without requiring the weak irreducibility condition; and (iv) if it is weakly reducible, then it can be decomposed into some weakly irreducible tensors. In addition, the problem of finding the largest eigenvalue of a symmetric nonnegative tensor is shown to be equivalent to finding the global solution of a convex optimization problem. Subsequently, algorithmic aspects for computing the largest eigenvalue of symmetric nonnegative tensors are discussed. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper presents several general properties of systematic absences that are available before unit-cell parameters and the space group have been determined. The properties are given in the form of distribution rules of Miller indices corresponding to systematic absences on a topograph. A topograph is a graph whose edges are associated with a set of four lattice vectors satisfying Ito's equation 2(| l 1 *|2 + | l 2 *|2) = | l 1 * + l 2 *|2 + | l 1 *− l 2 *|2. It is possible to integrate global information about extinct reflections by using topographs. As an example of the application of these rules, a new powder auto-indexing algorithm is introduced, focusing on its theoretical aspects. [ABSTRACT FROM AUTHOR]

The paper is dedicated to the decision of a problem of cutting tool diagnostics and working out of a remaining cutting tool life prediction algorithm. The example for practical realization of such algorithm on the CNC machine tool by machining under specified conditions is given. The question of working error compensation by means of corrective adjustment is considered. [ABSTRACT FROM AUTHOR]

Technologies that deploy algorithmic calculation are becoming ubiquitous to the homeland securitization of the war on terror. From the surveillance networks of the city subway to the biometric identifiers of new forms of border control, the possibility to identify “association rules” between people, places, objects and events has brought the logic of pre-emption into the most mundane and prosaic spaces. Yet, it is not the case that the turn to algorithmic calculation simply militarizes society, nor even that we are witnessing strictly a commercialization of security. Rather, algorithmic war is one form of Foucault's sense of a “continuation of war by other means”, where the war-like architectures of self/other, here/there, safe/risky, normal/suspicious are played out in the politics of daily life. This paper explores the situated interplay of algorithmic practices across commercial, security, and military spheres, revealing the violent geographies that are concealed in the glossy techno-science of algorithmic calculation. [ABSTRACT FROM AUTHOR]

Optimization of radiation treatment planning requires estimations of the normal tissue complication probability (NTCP). A number of models exist that estimate NTCP from a calculated dose distribution. Since different dose calculation algorithms use different approximations the dose distributions predicted for a given treatment will in general depend on the algorithm. The purpose of this work is to test whether the optimal NTCP parameter values change significantly when the dose calculation algorithm is changed. The treatment plans for 17 breast cancer patients have retrospectively been recalculated with a collapsed cone algorithm (CC) to compare the NTCP estimates for radiation pneumonitis with those obtained from the clinically used pencil beam algorithm (PB). For the PB calculations the NTCP parameters were taken from previously published values for three different models. For the CC calculations the parameters were fitted to give the same NTCP as for the PB calculations. This paper demonstrates that significant shifts of the NTCP parameter values are observed for three models, comparable in magnitude to the uncertainties of the published parameter values. Thus, it is important to quote the applied dose calculation algorithm when reporting estimates of NTCP parameters in order to ensure correct use of the models. [ABSTRACT FROM AUTHOR]

The paper presents an algorithm for calculating the three-dimensional Voronoi–Delaunay tessellation for an ensemble of spheres of different radii (additively-weighted Voronoi diagram). Data structure and output of the algorithm is oriented toward the exploration of the voids between the spheres. The main geometric construct that we develop is the Voronoi S-network (the network of vertices and edges of the Voronoi regions determined in relation to the surfaces of the spheres). General scheme of the algorithm and the key points of its realization are discussed. The principle of the algorithm is that for each determined site of the network we find its neighbor sites. Thus, starting from a known site of the network, we sequentially find the whole network. The starting site of the network is easily determined based on certain considerations. Geometric properties of ensembles of spheres of different radii are discussed, the conditions of applicability and limitations of the algorithm are indicated. The algorithm is capable of working with a wide variety of physical models, which may be represented as sets of spheres, including computer models of complex molecular systems. Emphasis was placed on the issue of increasing the efficiency of algorithm to work with large models (tens of thousands of atoms). It was demonstrated that the experimental CPU time increases linearly with the number of atoms in the system, O(n). © 2006 Wiley Periodicals, Inc. J Comput Chem, 2006 [ABSTRACT FROM AUTHOR]

A realizer of a triangulated plane graph G is a partition of interior edges of G, satisfying some conditions. The realizer has many applications, including graph drawing algorithms. Given a triangulated plane graph G, no algorithm to generate all realizers of G is known. In this paper, we first give an algorithm to generate all realizers. We first define a left canonical ordering for the vertices of an input graph, then show that there is a bijection between the left canonical orderings and realizers. Based on the bijection, we give an algorithm to generate all realizers. The algorithm generates each realizer in O(n) time without duplications, where n is the number of vertices in the graph. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 2, 89(7): 40–47, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecjb.20276 [ABSTRACT FROM AUTHOR]

This paper considers a regression frailty or transformation model in which the structural parameter is the vector of regression coefficients and the nuisance parameter is a vector of arbitrarily high dimension. It proposes jointly (implicitly) defined parameter estimators which have been proved to be consistent and asymptotically efficient, and develops an algorithmic procedure that provides these estimators. The behaviour of the algorithm is illustrated by analysing simulated and real data. [ABSTRACT FROM AUTHOR]

This paper presents a new efficient solution to the Dynamic Shortest Path Routing Problem, using the principles of Generalized Pursuit Learning. It proposes an efficient algorithm for maintaining shortest path routing trees in networks that undergo stochastic updates in their structure. It involves finding the shortest path in a stochastic network, where there are continuous probabilistically based updates in link-costs. In vast, rapidly changing telecommunications (wired or wireless) networks, where links go up and down continuously and rapidly, and where there are simultaneous random updates in link costs, the existing algorithms are inefficient. In such cases, shortest paths need to be computed within a very short time (often in the order of microseconds) by scanning and processing the minimal number of nodes and links. The proposed algorithm, referred to as the Generalized Pursuit Shortest Path Algorithm (GPSPA), will be very useful in this regard, because after convergence, it seems to be the best algorithm to-date for this purpose. Indeed, it has the advantage that it can be used to find the shortest path within the ‘statistical’ average network, which converges irrespective of whether there are new changes in link-costs or not. Existing algorithms are not characterized by such a behaviour inasmuch as they would recalculate the affected shortest paths after each link-cost update. The algorithm has been rigorously evaluated experimentally, and it has been found to be a few orders of magnitude superior to the algorithms available in the literature. Copyright © 2004 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This paper describes an optimization algorithm based on a special convex approximation technique and a robust numerical solution procedure. The employed approximation technique involves automatic adjustability in order to ensure good convergence properties. Additionally, it guaranties convexity and a special form of the approximate problems. Consequently, these problems can be transformed into very simple and quasi-unconstrained dual problems which are solved by a robust and reliable numerical solution procedure. A few examples illustrate the use of the algorithm. Copyright © 2002 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Simplified adaptive control (SAC) has simple structure and is readily implemented in real systems, but few real applications have as yet been reported. A discrete-time algorithm for SAC has recently been proposed by one of the authors. Although it solves the problem of unavoidable time delay arising in the discretization of the continuous-time algorithm, the algorithm generally produces a bounded output error between the controlled plant and the reference model due to a feedforward gain added in parallel to the controlled plant so as to satisfy the positive real (ASPR) property with almost complete rigor. This paper treats the applicability of the SAC algorithm to a real system, that is, the position control of a dc motor with variable load. The algorithm used here is modified, and the feedforward compensator is inserted in parallel not only to the controlled plant, but also to the reference model. The algorithm guarantees that the output error vanishes asymptotically. The control performance is examined by both simulation and testing of an actual system and is compared with that of a conventional PID control. These results illustrate satisfactory control performance and verify the applicability of the modified algorithm. © 2001 Scripta Technica, Electr Eng Jpn, 135(1): 33–42, 2001 [ABSTRACT FROM AUTHOR]

Let $X=\operatorname{Spec} B$ be an affine variety over a field of arbitrary characteristic, and suppose that there exists an action of a unipotent group (possibly neither smooth nor connected). The fundamental results are as follows. (1) An algorithm for computing invariants is given, by means of introducing a degree in the ring of functions of the variety, relative to the action. Therefore an algorithmic construction of the quotient, in a certain open set, is obtained. In the case of a Galois extension, $k\hookrightarrow B=K$, which is cyclic of degree $p=\text{ch} (k)$ (that is, such that the unipotent group is $G={\Bbb Z}/p {\Bbb Z}$), an element of minimal degree becomes an Artin--Schreier radical, and the method for computing invariants gives, in particular, the expression for any element of $K$ in terms of these radicals, with an explicit formula. This replaces the well-known formula of Lagrange (which is valid only when the degree of the extension and the characteristic are relatively prime) in the case of an extension of degree $p=\text{ch}(k)$. (2) In this paper we give an effective construction of a stable open subset where there is a quotient. In this sense we obtain an algebraic local criterion for the existence of a quotient in a neighbourhood. It is proved (provided the variety is normal) that, in the following cases, such an open set is the greatest one that admits a quotient: \begin{enumerate} \item[(a)] when the action is such that the orbits have dimension less than or equal to 1 (arbitrary characteristic) and, in particular, for any action of the additive group $G_a$; \item[(b)] in characteristic 0, when the action is proper (obtained from the results of Fauntleroy) or the group is abelian. 1991 Mathematics Subject Classification: primary 14L30; secondary 14D25, 14D20. [ABSTRACT FROM AUTHOR]

In this paper, we introduce and study a new class of generalized nonlinear implicit quasivariational inclusions for set-valued mappings. We construct some new iterative algorithms for this generalized nonlinear implicit quasivariational inclusions for set-valued mappings without compactness. We prove the existence of solutions for this generalized nonlinear implicit quasivariational inclusions for set-valued mappings without compactness and the convergence of iterative sequences generated by the algorithms. We also give an application to generalized nonlinear implicit variational inequalities. [ABSTRACT FROM AUTHOR]

In past studies, the digital straight-line segment is defined as a figure approximating the straight-line segment in the continuous space, by grid points in the discrete space. Because of this definition, the properties of the segment vary depending on the approximation process, which prevented the development of a general discussion. For this problem, the authors introduced a topology into the discrete space, and defined the digital straight-line segment using only the topology. As a result, the digital straight-line segment can be defined generally for various spaces and topologies, and the properties of the segment can be analyzed. In this paper, the properties of the digital straight-line segment are analyzed based on the 5-neighborhood concept. As the first step, the assertion that characterizes the digital straight-line segment, as well as five equivalent assertions are presented. Then, it is shown that by using those assertions, the corresponding segment generation algorithm can easily be obtained, and the figure generated by the segment generation algorithm which is known in the CG technology is the same as the proposed digital straight-line segment. © 1998 Scripta Technica. Electron Comm Jpn Pt 3, 81(6): 16–26, 1998 [ABSTRACT FROM AUTHOR]

Given, a graph G = (V, E), with two vertices s and t specified as the origin and destination, respectively; a positive integer K called the obstruction number; and (positive) weights l (·) on the edges; then, two players P1 and P2 play a game with the following rules. P1 starts from s, and tries to arrive at t by tracing an edge on each move. P2 cuts in his turn, P2 cuts some edges. The maximum total number of edges that P2 can cut is K during the game. It is assumed that both P1 and P2 can see the whole graph. P1 tries to minimize the sum of traveled edge weights (called the path length), and P2 tries to maximize the path length. This paper shows that the path length when the two players do their best can be determined in O(nk-l (m + n log n)) (m = |E| n = (|V|) time. It is also shown that the problem of deciding whether or not the path length when the two players do their best is not greater than a certain positive integer is P-SPACE-complete, even if the weight on each edge is 1. © 1998 Scripta Technica. Electron Comm Jpn Pt 3, 81(2): 13–23, 1998 [ABSTRACT FROM AUTHOR]

Various algorithms have been proposed for the problem of drawing rooted ordered trees. As one of them, Unno and colleagues [1] presented an O(n3) time algorithm that (1) produces an initial drawing of a given tree T, and then (2) finds a narrower drawing by repeatedly moving subtrees (n is the number of nodes in T). In this paper, we show that the same drawing can be obtained more efficiently by maintaining the contours of subtrees. If a natural restriction is imposed on the sizes of nodes, our method can be executed in a time O(n·α(n, n)), where α is a functional inverse of Ackermann's function. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 3, 80(5): 31–41, 1997 [ABSTRACT FROM AUTHOR]

This paper discusses the problems of finding one of the largest similar substructures in tree Tb to tree Ta, where both Ta and Tb are rooted and ordered trees (RO-trees) or unrooted and cyclically ordered trees (CO-trees). A maximal closest common ancestor mapping and a largest similar substructure in Tb to Ta based on this mapping are defined and two algorithms are proposed for finding one of the largest similar substructures for RO-trees and that for CO-trees. The time and space complexities of the algorithm for RO-trees are OT(NaNb) and OS(NaNb), respectively; and those of the algorithm for CO-trees are OT(mambNaNb) and OS((ma + mb)NaNb), respectively, where ma(mb) and Na(Nb) are the largest degree of a vertex and the number of vertices of Ta(Tb), respectively. © 1997 Scripta Technica, Inc. Electron Comm Jpn Pt 3, 80(2): 92–104, 1997 [ABSTRACT FROM AUTHOR]

Assume that G is an undirected planar graph and the edge length of G is nonnegative real number. When k terminal pairs are specified on two specified face boundaries, this paper gives an algorithm that derives the "noncrossing paths" with the minimum sum of lengths that connects the respective terminal pairs. By the noncrossing paths is meant the paths which do not cross on the plane, although the point or the edge may be shared. The computation time of the proposed algorithm is O(n log n), where n is the number of points on the planar graph G; k need not to be a constant. [ABSTRACT FROM AUTHOR]

In this paper authors present the fuzzy algorithm of sensor fusion for discriminating material properties with touch sensors. The proposed algorithm is based on fuzzy theory, and there the notions of adaptation grade function, maximum similarity α and boundary value γ are introduced for expressing the categories of samples. For verifying the algorithm, numerical simulation is performed. It resulted in good classification for discrimination of materials such as iron, aluminum, copper, bronze, gum, wood, styrene foam, etc. The database used is based on the experimental results with our proposed touch sensors. Our final target is to develop an artificial skin tactile sensing system. © 1997 Scripta Technica, Inc. Electr Eng Jpn, 118 (1): 61–70, 1997 [ABSTRACT FROM AUTHOR]

Summary: Recently, the routing problem in vehicular ad hoc networks is one of the most vital research. Despite the variety of the proposed approaches and the development of communications technologies, the routing problem in VANET suffers from the high speed of vehicles and the repetitive failures in communications. In this paper, we adjusted the well‐known K‐medoids clustering algorithm to improve the network stability and to increase the lifetime of all established links. First, the number of clusters and the initial cluster heads will not be selected randomly as usual, but based on mathematical formula considering the environment size and the available transmission ranges. Then the assignment of nodes to clusters in both k‐medoids phases will be carried out according to several metrics including direction, relative speed, and proximity. To the best of our knowledge, our proposed model is the first that introduces the new metric named "node disconnection frequency." This metric prevents nodes with volatile and suspicious behavior to be elected as a new CH. This screening ensures that the new CH retains its property as long as possible and thus increases the network stability. Empirical results confirm that in addition to the convergence speed that characterizes our adjusted K‐medoids clustering algorithm (AKCA), the proposed model achieves more stability and robustness when compared with most recent approaches designed for the same objective. [ABSTRACT FROM AUTHOR]

A new method is developed for antenna radiation pattern analysis using spherical near fields and the uniform geometrical theory of diffraction (UTD). The spherically scanned tangential electric near field is transformed to the present one to more efficiently obtain the far-field antenna pattern by employing UTD. Examples illustrating the accuracy and speed of the method presented in this paper for large antennas are presented. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 21: 390–392, 1999. [ABSTRACT FROM AUTHOR]