An emerging trend in mobile communications is the parallel usage of multiple radio technologies in mobile devices, tablets and other communications modules. In order to support this parallel operation, the devices are equipped with multiple radio transceivers, which are located extremely close to each other. When the different radio technologies operate simultaneously these transceivers interfe...

Wireless protocols in the unlicensed spectrum are developed for different requirements in terms of range and power, which makes them difficult to coexist in the same unlicensed spectrum. One such example is Zigbee and WiFi coexistence where low-power Zigbee nodes are frequently starved by WiFi nodes. Recent standardization efforts of short range IEEE 802.11af and long range IEEE 802.22 in the T...

We characterize all coexistent pairs of qubit effects. This gives an exhaustive description of all pairs of events allowed, in principle, to occur in a single qubit measurement. The characterization consists of three disjoint conditions which are easy to check for a given pair of effects. Known special cases are shown to follow from our general characterization theorem.

Two quantum events, represented by positive operators (effects), are coexistent if they can occur as possible outcomes in a single measurement scheme. Equivalently, the corresponding effects are coexistent if and only if they are contained in the ranges of a single (joint) observable. Here we give a necessary and sufficient condition for the coexistence of a pair of qubit effects.

An analytical cluster wetting model is developed, based on minimization of an expression for the free energy, for solid-liquid equilibrium coexistence states in clusters. For given materials’ characteristic interfacial energies of the solid and liquid phases, the model relates the fraction of the solid-phase area wetted by the liquid to the volume fraction of the two phases. Equilibrium coexist...

Quantum operations are used to describe the observed probability distributions and conditional states of the measured system. In this paper, we address the problem of their joint measurability (coexistence). We derive two equivalent coexistence criteria. The two most common classes of operations — Lüders operations and conditional state preparators — are analyzed. It is shown that Lüders operat...

The witness set W(A, B) for two quantum effects A, B is the set of effects that verify the coexistence of A and B. We first study the properties of W(A, B). We then introduce a measure of sharpness Sn(A) for an n-dimensional quantum effect A. We show that S2(A) has natural properties that a measure of sharpness should possess and conjecture that Sn(A) also has these properties for n > 2. Finall...

8 Invasive alien predators can impose strong selection on native prey populations and induce rapid 9 evolutionary change in the invaded communities. However, studies on evolutionary responses to 10 invasive predators are often complicated by the lack of replicate populations differing in 11 coexistence time with the predator, which would allow determining how prey traits change during 12 the in...

Competitive exclusion n species cannot coexist on fewer than n limiting resources in a constant and isolated environment has been a central ecological principle for the past century. Since empirical studies cannot universally demonstrate exclusion, this principle has mainly relied on mathematical proofs. Here we investigate the predictions of a new approach to derive functional responses in con...

Cognitive Radio (CR) is seen as one of the enabling technologies for realizing a new spectrum access paradigm, viz. Opportunistic Spectrum Sharing (OSS). IEEE 802.22 is the world’s first wireless standard based on CR technology. It defines the air interface for a wireless regional area network (WRAN) that uses fallow segments of the licensed (incumbent) TV broadcast bands. CR technology enables...