This paper provides additional empirical evidence confirming a recently proposed theory on the evolution of oscillations in congested traffic. It also proposes an improved method for computing the variation in oscilla...
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This paper provides additional empirical evidence confirming a recently proposed theory on the evolution of oscillations in congested traffic. It also proposes an improved method for computing the variation in oscillation amplitude, consisting in evaluating the oscillation amplitude along characteristic lines that travel at a constant wave speed. It is also shown that the theory is robust in that approximate input parameters can be used with little loss in accuracy. The paper, in addition, provides a finding on the evolution of oscillations in freeway segments with no entrances or exits. Although previous studies found an increase in oscillation amplitude in such segments, data in this study indicate that this is not the case in general. This finding can have important implications for understanding driver behavior in homogeneous freeway segments.
An ordered binary decision diagram (OBDD) is a graph representation of a Boolean function. In this paper, the size of ordered binary decision diagrams representing threshold functions is discussed. We consider two cas...
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An ordered binary decision diagram (OBDD) is a graph representation of a Boolean function. In this paper, the size of ordered binary decision diagrams representing threshold functions is discussed. We consider two cases: the case when a variable ordering is given and the case when it is adaptively chosen. We show 1) O(2(n/2)) upper bound for both cases, 2) Omega(2(n/2)) lower bound for the former case and 3) Omega(n2(root n/2)) lower bound for the latter case. We also show some relations between the variable ordering and the size of OBDDs representing threshold functions.
The (in)equational properties of iteration, i.e., least (pre-)fixed point solutions over cpo's, are captured by the axioms of iteration theories. All known axiomatizations of iteration theories consist of the Conw...
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The (in)equational properties of iteration, i.e., least (pre-)fixed point solutions over cpo's, are captured by the axioms of iteration theories. All known axiomatizations of iteration theories consist of the Conway identities and a complicated equation scheme, the commutative identity. The results of this paper show that the commutative identity is implied by the Conway identities and a weak form of the Park induction principle. Hence, we obtain a simple first order axiomatization of the (in)equational theory of iteration. It follows that a few simple identities and a weak form of the Scott induction principle, formulated to involve only inequations, are also complete. We also show that the Conway identities and the Park induction principle are not complete for the universal Horn theory of iteration.
Simple and efficient numerical procedures for evaluating the gradient of Helmholtz-type potentials are presented. The convergence behavior of both normal and tangential components of the gradient is examined. It is al...
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Simple and efficient numerical procedures for evaluating the gradient of Helmholtz-type potentials are presented. The convergence behavior of both normal and tangential components of the gradient is examined. It is also shown that the scheme for handling near-hypersingular integrals is effective for handling nearly singular potential integrals as well, so the same quadrature scheme may be used for both simultaneously.
Reversible gate has been one of the emerging research areas that ensure continual process of innovation trends that explore and utilizes the resources. Due to the increasing power consumption of electronic circuits, i...
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Tailoring modal competition inside lasers is enabling novel sources of complex light-and new approaches to light-based computation. In the 1960s, early laser resonator theory established that even simple cavities coul...
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Tailoring modal competition inside lasers is enabling novel sources of complex light-and new approaches to light-based computation. In the 1960s, early laser resonator theory established that even simple cavities could produce complex structured modes.
Cyber-physical systems (CPSs) integrate computing and communication capabilities to monitor and control physical processes. In order to do so, communication networks are commonly used to connect sensors, actuators, an...
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Rate monotonic scheduling theory puts real-time software engineering on a sound analytical footing. The authors review the theory and its implications for Ada
Rate monotonic scheduling theory puts real-time software engineering on a sound analytical footing. The authors review the theory and its implications for Ada
Bots, or programs designed to engage in social spaces and perform automated tasks, are typically understood as automated tools or as social "chatbots." In this paper, we consider bots’ place alongside users...
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In contrast to deterministic or nondeterministic computation, it is a fundamental open problem in randomized computation how to separate different randomized time classes (at this point we do not even know how to sepa...
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In contrast to deterministic or nondeterministic computation, it is a fundamental open problem in randomized computation how to separate different randomized time classes (at this point we do not even know how to separate linear randomized time from O(n(logn)) randomized time) or how to compare them relative to corresponding deterministic time classes. In other words, we are far from understanding the power of random coin tosses in the computation, and the possible ways of simulating them deterministically. In this paper we study the relative power of linear and polynomial randomized time compared with exponential deterministic time. Surprisingly, we are able to construct an oracle A such that exponential time (with or without the oracle A) is simulated by linear time Las Vegas algorithms using the oracle A. For Las Vegas polynomial time (ZPP) this will mean the following equalities of the time classes: ZPP(A)=EXPTIME(A)=EXPTIME (=DTIME(2(poly))). Furthermore, for all the sets M subset of or equal to Sigma*, M less than or equal to(UR)(A) over bar reversible arrow M epsilon EXPTIME (less than or equal to(UR) being unfaithful polynomial random reduction, cf. [10]). Thus (A) over bar is less than or equal to(UR) complete for EXPTIME, but interestingly not NP-hard under (deterministic) polynomial reduction unless EXPTIME=NEXPTIME. We also prove, for the first time, that randomized reductions are exponentially more powerful than deterministic or nondeterministic ones (cf. [2]). Moreover, a set B is constructed such that Monte Carlo polynomial time (BPP) under the oracle B is exponentially more powerful than deterministic time with nondeterministic oracles, more precisely, BPPB=Delta(2)EXPTIME(B)=Delta(2)EXPTIME (=DTIME(2(polyNTIME(n)).
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