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The natural order of events: how speakers of different languages represent events nonverbally
No full textTo test whether the language we speak influences our behavior even when we are not speaking, we asked speakers of four languages differing in their predominant word orders (English, Turkish, Spanish, and Chinese) to perform two nonverbal tasks: a communicative task (describing an event by using gesture without speech) and a noncommunicative task (reconstructing an event with pictures). We found that the word orders speakers used in their everyday speech did not influence their nonverbal behavior. Surprisingly, speakers of all four languages used the same order and on both nonverbal tasks. This order, actor-patient-act, is analogous to the subject-object-verb pattern found in many languages of the world and, importantly, in newly developing gestural languages. The findings provide evidence for a natural order that we impose on events when describing and reconstructing them nonverbally and exploit when constructing language anew
Nonisolated forms of rational triple point singularities of surfaces and their resolutions
No full textWe give a list of nonisolated hypersurface singularities of which normalizations are the rational triple point singularities of surfaces and construct their minimal resolution graphs by a method introduced by Oka for isolated complete intersection singularities. We also show that nonisolated forms of rational triple point singularities and their normalizations are both Newton non-degenerate
Stochastic target problems, dynamic programming, and viscosity solutions
No full textIn this paper, we define and study a new class of optimal stochastic control problems which is closely related to the theory of backward SDEs and forward-backward SDEs. The controlled process (X-nu, Y-nu) takes values in R-d x R and a given initial data for X-nu (0). Then the control problem is to find the minimal initial data for Y-nu so that it reaches a stochastic target at a specified terminal time T. The main application is from financial mathematics, in which the process X-nu is related to stock price, Y-nu is the wealth process, and nu is the portfolio. We introduce a new dynamic programming principle and prove that the value function of the stochastic target problem is a discontinuous viscosity solution of the associated dynamic programming equation. The boundary conditions are also shown to solve a first order variational inequality in the discontinuous viscosity sense. This provides a unique characterization of the value function which is the minimal initial data for Y-nu
Monolithic fabrication of silicon nanowires bridging thick silicon structures
No full textA monolithic process is developed for the fabrication of Si nanowires within thick Si substrates. A combination of anisotropic etch and sidewall passivation is utilized to protect and release Si lines during the subsequent deep etch. An etch depth of 10 μm is demonstrated with a future prospect for 50 μm opening up new possibilities for the deterministic integration of nanowires with microsystems. Nanowires with in-plane dimensions as low as 20 nm and aspect ratios up to 150 are obtained. Nanomechanical characterization through bending tests further confirms structural integrity of the connection between nanowires and anchoring Si microstructures
A new crossover operator for single machine total weighted tardiness problem with sequence dependent setup times
No full textThe single machine total weighted tardiness problem with sequence dependent setup times is a challenging and heavily studied problem. This problem is NP-hard, so several heuristics have been proposed in the literature so far. One of them is the genetic algorithm. The genetic algorithm is both powerful solution technique and applicable to wide range of different problem types, although its performance is heavily parameter and operator dependent. It is seen in literature that the well-conducted and adapted genetic algorithm operators and parameters increase the solution quality. In this study, a new crossover operator is proposed for the single machine with sequence dependent setup times problem to minimize the total weighted tardiness. The proposed crossover operator improves the relative positions by using apparent tardiness cost with setups (ATCS) heuristic while preserving the absolute positions. These are the two main aspects of the permutation type crossover operators for scheduling problems. The performance of the proposed crossover operator is tested by comparing it with partially mapped crossover (PMX) in different test cases using benchmark instances from literature. It is shown that the proposed ATCS based crossover operator gives better results than PMX in all test problems
Serum alkaline phosphatase may play a role in the differential diagnosis of sarcoidosis and tuberculosis
No full textBackground: Reaching the differential diagnosis of tuberculosis and sarcoidosis can be difficult due to granulomatous inflammation. The aim of this study was to determine alkaline phosphatase (ALP) activity in serum for the differential diagnosis of tuberculosis and sarcoidosis. Methods: This study comprised 242 subjects: 105 acid-fast bacilli (AFB) positive and/or culture-positive patients with pulmonary tuberculosis, 90 patients with biopsyproven sarcoidosis and a control group consisting of 47 healthy controls were included. ALP activity was measured in serum at the first admission of the patients. Results: The mean serum ALP was 112.74 +/- 55.14 IU/L in pulmonary tuberculosis, 76.14 +/- 34.23 IU/L in sarcoidosis, and 66.87 +/- 18.49 IU/L in the control group, respectively. There was a statistically significant difference between the patient population and the control group (P = 0.03). Also, there was a statistically significant difference between the tuberculosis and sarcoidosis groups (P = 0.034). According to the comparison of tuberculosis and sarcoidosis, the cut-off value was determined as 71.50 IU/L, which had sensitivity of 80%, specificity of 51%, PPV of 66%, NPV of 69%, accuracy of 67%, and the AUC was 0.728. Conclusion: ALP, as a little-known marker for tuberculosis and sarcoidosis, was significantly increased in the pulmonary tuberculosis group compared with the sarcoidosis group. As such, it may be a useful tool for the differentiation of tuberculosis and sarcoidosis
Near infrared elastic light scattering by a silicon microsphere
No full textWe observed high quality elastic light scattering from a silicon microsphere in the standard telecommunication band. A tunable diode laser was used as the excitation source and a single mode silica optical fiber setup delivered the input laser light to the microsphere. The silicon microsphere was manipulated on the silica optical fiber half coupler (OFHC) to effectively couple the evanescent laser field to the microsphere thus exciting the whispering gallery modes (WGM's). We observed high quality factor WGM's which can lead to novel geometries and applications for silicon microsphere based optoelectronic devices, such as filters, modulators, and detectors
Optical scanners for high resolution RSD systems
No full textThis paper outlines the design trade-offs and measured results of scanner architectures for use in high resolution Retinal Scanning Displays: Mechanical resonant for horizontal scanning, and MEMS-based pinch correction and vertical linear scanners. Analysis steps and techniques used to model and minimize dynamic deformations are covered. This paper also discusses two types of scanners and associated mirror flatness issues. Dynamic flatness modeling and performance results are presented, followed by thermally induced deformations and possible athermalize solutions for MEMS-type scanning mirrors. Theory, FEA dynamic and thermal analysis, experimental results, and methods to reduce mirror deformation are discussed
Solvation of carbonaceous molecules by para-H-2 and ortho-D-2 clusters. I. Polycyclic aromatic hydrocarbons
No full textThis work theoretically examines the progressive coating of planar polycyclic aromatic hydrocarbon (PAH) molecules ranging from benzene to circumcoronene (C54H18) by para-hydrogen and ortho-deuterium. The coarse-grained Silvera-Goldman potential has been extended to model the interactions between hydrogen molecules and individual atoms of the PAH and parametrized against quantum chemical calculations for benzene-H-2. Path-integral molecular dynamics simulations at 2 K were performed for increasingly large amounts of hydrogen coating the PAH up to the first solvation shell and beyond. From the simulations, various properties were determined such as the size of the first shell and its thickness as well as the solvation energy. The degree of delocalization was notably quantified from an energy landscape perspective, by monitoring the fluctuations among inherent structures sampled by the trajectories. Our results generally demonstrate a high degree of localization owing to relatively strong interactions between hydrogen and the PAH, and qualitatively minor isotopic effects. In the limit of large hydrogen amounts, the shell size and solvation energy both follow approximate linear relations with the numbers of carbon and hydrogen in the PAH
Ab initio quantum dynamics with very weak van der Waals interactions: structure and stability of small Li-2((1)Sigma(+)(g))-(He)(n) clusters
No full textThe potential energy surface (PES) for the interaction between Li-2((1)Sigma(g)(+)) and He-4 has been computed using an accurate, post-Hartree-Fock quantum calculation for its ground electronic state. The orientational anisotropy of the forces and the interplay between repulsive and attractive effects within the PES are analyzed to extract information on the possible existence of bound states in the triatomic system. The structures of a few of the Li-2(He)(n) small clusters are examined by comparing a classical approach with a full quantum one to generate bound configurations and to extract information on the possible spatial arrangements of the smaller clusters via a vis the location of the Li-2 dopant. Some significant consequences on the Li-2 behavior in larger clusters and droplets are drawn from the above findings