Optimal design of gears contact interface modification for an objective as minimum impact resistance of initial meshing-in time domain

Meccanica - In gear pair actual alternating meshing process, the comprehensive errors of the transmission system and the thermal elastic deformation of the teeth body cause the gears in the meshing...     

The identity is isolated among composition operators

Let be the Banach algebra of bounded holomorphic functions on the open unit ball of a Banach space. We show that the identity operator is an isolated point in the space of composition operators on . This answers a conjecture of Aron, Galindo and Lindström.

     

Optically controlled seeding of Raman forward scattering and injection of electrons in a self-modulated laser-wakefield accelerator

Optical seeding of plasma waves and the injection of electrons are key issues in self-modulated laser-wakefield accelerators. By implementing a copropagating laser prepulse with proper timing, we are able to control the growth of Raman forward scattering and the production of accelerated electrons. The dependence of the Raman intensity on prepulse timing indicates that the seeding of Raman forward scattering is dominated by the ionization-induced wakefield, and the dependence of the divergence and number of accelerated electrons further reveals that the stimulated Raman backward scattering of the prepulse plays the essential role of injecting hot electrons into the fast plasma wave driven by the main pulse.     

Carbon dots doped with heteroatoms for fluorescent bioimaging: a review

Carbon dots (CDs) possess superior fluorescent properties in that they do not blink, are biocompatible, chemically inert, have small size and well tunable photoluminescence (PL), can be easily functionalized with biomolecules, and can be multi-photon excited to give up-converted PL. This review (with 141 refs.) summarizes recent progress in the field of imaging using carbon dots doped with heteroatoms (X-CDs). Following an introduction, we discuss top-down and bottom-up strategies for synthesis and methods for surface modification. We also compare the differences in synthesis for undoped CDs and X-CDs. Specifically, CDs doped with heteroelemets nitrogen, phosphorus, sulfur, selenium, boron and silicium are treated. We then discuss method for determination of the properties (particle size, ZP), how doping affects fluorescence (spectra, quantum yields, decay times), and how dopants affect upconversion (UC, anti-Stokes luminescence). We finally review the progress made in fluorescent imaging of cells tissue, and other biomatter. This review also gives new hints on how to use synthetic methods for tuning the structure of X-CDs, how doping affects properties, and how to achieve new bioimaging applications.

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Graphical abstract Carbon dots doped with heteroatoms (X-CDs) are a kind of fluorescent nanomaterials that display bright fluorescence, high quantum yield, photostability, biocompatibility and low toxicity. Hence, they possess large potential for both in-vitro and in-vivo bioimaging.

     

Cold nuclear matter effects on J/ψ yields as a function of rapidity and nuclear geometry in d+A collisions at sqrt[s(NN)]=200 GeV

We present measurements of J/ψ yields in d+Au collisions at sqrt[s(NN)]=200 GeV recorded by the PHENIX experiment and compare them with yields in p+p collisions at the same energy per nucleon-nucleon collision. The measurements cover a large kinematic range in J/ψ rapidity (-2.2相似文献   

Optimal purchase of two-itemized drugs for a disease

This paper submits a mathematical model called the two-itemized drugs purchasing decision (TDPD) model to conduct the optimal purchase of two-itemized drugs for healing a given disease. This TDPD model considers not only the annual estimated number of patients suffering from the given disease, the treatment courses, and the unit profit of each drug, but also the strength of the patient's perception on treatment quality, the different purchasing price of each drug with quantity discounts, the ordering cost, the holding cost, and other related costs to determine the optimal order quantity of each drug for achieving the maximum profit. A computerized solving program proposed in this paper applies tabu search technique as the main program and the all-units quantity discounts for economic order quantity as the sub-program to solve such a combinatorial problem, as well as perform sensitivity analyses on the changes by the strength of the patient's perception on treatment quality and the changes of annual estimated number of patients for the given disease. Two drugs, Lipitor and Gemnpid, to heal a disease ‘Hyperlipidaemia’ are considered as a case example in this study. This paper contributes a prototype quantitative method of purchasing decision for a given disease to a decision-maker with profound insights.     

Solving project scheduling problems with a heuristic learning algorithm

We have developed an approach to implement a real time admissible heuristic search algorithm to solve project scheduling problems. This algorithm is characterised by the complete heuristic learning process: state selection, heuristic learning, and search path review. This implementation approach is based on the dynamic nature of the activity status and the resource availability of a project. It consists of states, state transition operator, heuristic estimate, and the cost of transition between states. The performance analysis shows that the accumulation of heuristic learning during the search process has led to the re-scheduling of resource dominating activities, which is a major factor in controlling the overall project completion time.     

Exposure of monomolecular lithographic patterns to ambient: an X-ray photoemission spectromicroscopy study

Patterned self-assembled monolayers (SAMs) of alkanethiolates (AT) on Au and Ag substrates were imaged and characterized by scanning photoelectron microscopy (SPEM). The patterns were prepared in situ by direct writing with the zone-plate-focused X-ray beam provided by the SPEM station. Whereas both AT/Au and AT/Ag behaved alike upon the irradiation, which resulted in similar contrasts in the fabricated patterns and similar microspot spectra from the irradiated areas, the intensity relationship between the patterned and nonpatterned areas changed by different pathways for the Au and Ag substrates after the exposure of the patterns to ambient. The SPEM data imply that weakly bound molecular fragments are desorbed from the irradiated areas upon air exposure in the case of Ag, whereas adsorption of airborne molecules from ambient occurs for the Au substrate. The origin of the observed differences is presumably related to the specific branching patterns of irradiation-induced modification of AT/Au and AT/Ag.     

Multi-criteria analysis for dredger dispatching under uncertainty

Dredger dispatching is a complex decision making process in which multiple requirements and uncertain site conditions have to be taken into consideration simultaneously, for a specific dredging task. In evaluating the suitability of dredgers, besides quantitative assessments, qualitative assessments are often required to deal with uncertainty, subjectiveness and imprecision, which are best represented with fuzzy data. This paper formulates dredger dispatching as a fuzzy multi-criteria analysis model, and presents an effective algorithm for handling both crisp and fuzzy data in a straightforward manner. As a result, effective decisions can be made based on consistent evaluation results. An empirical study of a real case in China is conducted to demonstrate the applicability of the model. With its simplicity in both concept and computation, the model can be implemented as an effective decision aid in selecting dredgers for specific dredging tasks.