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1.
Investigation of ink formulation options with the purpose to obtain color-gamut-optimal set of Cyan Magenta and Yellow CMY inks is reported. Implementation of the thickness dependent Kubelka-Munk model on multiple ink layers having different and well-defined thicknesses, provides characteristic absorption and scattering (K, S ) spectra of the ink ingredients. These data enable accurate computation of the reflectance spectrum and thus the L*a*b* color coordinates for any given ink thickness or substrate. Pigment materials investigated are quinacridone as magenta, copper-phthalocyanine as cyan, and arylide yellow. Scaling the peak of the absorption band to the number of molecules per unit area for the specific pigments studied in this article provides the molar extinction coefficients, 1.21 × 104 , 4.7 × 104 , and 3.3 × 104 cm2/millimole respectively, regardless of the different ink formulations used, in accord with Avogadro's principle. Having a set of three pairs of K, S spectra is used to compute the color gamut of any CMY color combination in the L*a*b* space as a function of ink layer thickness and formulation. Using an iterative algorithm, a color-gamut-optimal set of CMY inks is obtained.  相似文献   
2.
Many interactions between searching agents and their elusive targets are composed of a succession of steps, whether in the context of immune systems, predation or counterterrorism. In the simplest case, a two-step process starts with a search-and-hide phase, also called a hide-and-seek phase, followed by a round of pursuit–escape. Our aim is to link these two processes, usually analysed separately and with different models, in a single game theory context. We define a matrix game in which a searcher looks at a fixed number of discrete locations only once each searching for a hider, which can escape with varying probabilities according to its location. The value of the game is the overall probability of capture after k looks. The optimal search and hide strategies are described. If a searcher looks only once into any of the locations, an optimal hider chooses it''s hiding place so as to make all locations equally attractive. This optimal strategy remains true as long as the number of looks is below an easily calculated threshold; however, above this threshold, the optimal position for the hider is where it has the highest probability of escaping once spotted.  相似文献   
3.
Multi-gate transistors enable the pace of Moore's Law for another decade. In its 22 nm technology node Intel switched to multi-gate transistors called TriGate, whereas IBM, TSMC, Samsung and others will do so in their 20 nm and 14 nm nodes with multi-gate transistors called FinFET. Several recent publications studied the drawing of multi-gate transistors layout. Designing new VLSI cell libraries and blocks requires massive re-drawing of layout. Hard-IP reuse is an alternative method taking advantage of existing source layout by automatically mapping it into new target technology, which was used in Intel's Tick-Tock marketing strategy for several product generations. This paper presents a cell-level hard-IP reuse algorithm, converting planar transistors to multi-gate ones. We show an automatic, robust transformation of bulk diffusion polygons into fins, while addressing the key requirements of cell libraries, as maximizing performance and interface compatibility across a variety of driving strength. We present a layout conversion flow comprising time-efficient geometric manipulations and discrete optimization algorithms, while generating manually drawn layout quality. Those can easily be used in composing larger functional blocks.  相似文献   
4.
The determination of the time averages of continuous functions or discrete time sequences is important for various problems in physics and engineering, and the generalized final‐value theorems of the Laplace and z‐transforms, relevant to functions and sequences not having a limit at infinity, but having a well‐defined average, can be very helpful in this determination. In the present contribution, we complete the proofs of these theorems and extend them to more general time functions and sequences. Besides formal proofs, some simple examples and heuristic and pedagogical comments on the physical nature of the limiting processes defining the averaging are given. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
5.
Inorganic oxidizing agents are used in various explosive mixtures that are analysed by analytical chemists. Among them are dynamites, ANFO, black powder, match heads, pyrotechnical devices and home-made bombs. The crucial step in post explosion analysis is the extraction and purification of the explosive residues from the debris. A unique, fast and selective extraction technique for inorganic oxidizing agents is described in this paper. The debris are first extracted with water to yield an aqueous solution of the ions. Oxidizing anions such as nitrate and chlorate, are selectively transfered into the organic phase by the use of lipophilic quarternary ammonium cations. Other anions such as carbonate, sulphate and nitrite are not extracted into the organic phase under these conditions. The extracted anions are then identified by infra-red spectrometry and chemical spot tests.  相似文献   
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7.
We define the convexity rank of a set of points to be the portion of mutually visible pairs of points out of the total number of pairs. Based on this definition of weak convexity, we introduce a spectral method that decomposes a given shape into weakly convex regions. The decomposition is applied without explicitly measuring the convexity rank. The method merely amounts to a spectral clustering of a matrix representing the all‐pairs line of sight. Our method can be directly applied on an oriented point cloud and does not require any topological information, nor explicit concavity or convexity measures. We demonstrate the efficiency of our algorithm on a large number of examples and compare them qualitatively with competitive approaches.  相似文献   
8.
The reaction of isonicotinoyl hydrazone of pyridoxal (PIH), a biologically active iron-carrier, with FeSO4-7H20 at pH ∼ 6 generates the delta, lamda species of the N,N-trans-O,O-cis-cis coordination isomer of an iron(III) complex with iron-to-ligand ratio of 1:2. The dark red-brown crystals are monoclinic, space group C2/c, with unit-cell dimensions a = 14.487(2), b = 18.586(2), c = 27.508(4) Å, β = 102.76(3)°, and Z = 8. The coordination around the metal is distorted octahedral and involves the protonated organic ligands, which are chelated through the phenolic oxygen [Fe-O1 1.941(6), Fe-O1′ 1.938(6)], an enolic form of the carbonyl oxygen [Fe-O3 2.017(6), Fe-O3′ 2.018(6)] and the azomethinic nitrogen [Fe-N2 2.133(8), Fe-N2′ 2.133(8)]. Packing is determined by systems of N-H….O and O-H….O hydrogen bonds involving the protonated pyridoxal nitrogens, the pyridoxal hydroxymethyl group, and the [SO4]2− group. The Mössbauer spectra at different temperatures (300 K, 88 K and 4.1 K) clearly prove that the iron atom in the complex is in a high-spin trivalent state.  相似文献   
9.
We study the message complexity of the problem of distributively electing a leader in chordal rings. Such networks consist of a basic ring with additional links, the extreme cases being the oriented ring and the complete graph with a full sense of direction. We present a general election algorithm for these networks, and prove its optimality. As a corollary, we show thatO(logn) chords at each processor suffice to obtain an algorithm that uses at mostO(n) messages; this improves and extends a previous work, where an algorithm, also usingO(n) messages, was suggested for the case where alln-1 chords exist (the oriented complete network).  相似文献   
10.
Flat Concurrent Prolog is a simple, practical, concurrent programming language which has an efficient uniprocessor implementation. This paper describes an initial parallel implementation of the language; it consists of an interpreter implemented on an Intel iPSC Hypercube. The parallel execution of concurrent logic programming languages involves many nontrivial implementation problems. Some of these problems are well known and have been treated extensively in the literature. The most difficult task is to integrate problem solutions in a coherent and efficient manner. The algorithm presented has been useful in providing insights into the major problems and includes a number of novel ideas to simplify implementation. It does not attempt to solve all the problems involved but rather provides a workable basis for current and future research. The algorithm is under ongoing refinement, simplification and improvement.  相似文献   
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