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41.
A rod-based model for plant growth and branching is developed in this paper. Specifically, Euler's theory of the elastica is modified to accommodate growth and remodeling. In addition, branching is characterized using a configuration force and evolution equations are postulated for the flexural stiffness and intrinsic curvature. The theory is illustrated with examples of multiple static equilibria of a branched plant and the remodeling and tip growth of a plant stem under gravitational loading.  相似文献   
42.
Journal of Fourier Analysis and Applications - We introduce the discrete frequency function as a possible new approach to understanding the discrete Hardy–Littlewood maximal function....  相似文献   
43.
44.
Journal of Radioanalytical and Nuclear Chemistry - Responses of the hand-held gamma monitors available for the ambient dose equivalent rate measurements in the Federation of Bosnia and Herzegovina...  相似文献   
45.
Transport in Porous Media - Stress dependency of permeability of porous rocks is described by means of a theoretical elastic cylindrical pore-shell model. This model is developed based on a bundle...  相似文献   
46.
The parameters affecting the differences between the solutions to problems related with incompressible rubber—like shells of revolution, undergoing axisymmetric finite strains and rotations, corresponding to two different definitions of the reference surface of deformed rubber-like shells of revolution are obtained through an asymptotic analysis.  相似文献   
47.
This paper presents a heuristic algorithm for determining order quantities for multiple items given incremental quantity discounts and a single resourse constraint. The heuristic is based on Lagrangian relaxation. The performance of the heuristic is compared, for small problems, with a procedure that generates optimal solutions. Results from computational experiments are given that demonstrate the quality and computational efficiency of the heuristic algorithm.  相似文献   
48.
The determination of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonate (PFOS) in food and beverages sold in Turkey was carried out using liquid chromatography–tandem mass spectrometry (LC-MS/MS). A total of 123 samples of selected food and beverages such as fish, meat, offal, egg, cracker, chips, cake, chocolate, vegetable, milk and juice were examined. The highest PFOA concentrations were determined in cow meat (5.15 ng g?1), cow kidney (5.65 ng g?1), cow spleen (5.06 ng g?1) and chicken liver (5.02 ng g?1). The highest PFOS levels were found in horse mackerel (52.43 ng g?1), pike-perch (45.87 ng g?1), sardine (42.83 ng g?1) and black cod (41.33 ng g?1). Fish was found to be major source of the PFOS intake, while meat and offal were found to be major sources of the PFOA intake.  相似文献   
49.
Chaos theory is considered a novel way of understanding the behaviour of nonlinear dynamic systems. It is well known that the evaluation of chaotic systems is dependent on initial conditions since exponential growth error is a common characteristic. This present paper evaluates the effects of a nonlinear dynamic system in Istanbul Stock Exchange, based on time series. The reliability of predicting stock behaviour depends on this fact. In other words, the aim is to prove that if ISE daily index return shows chaotic behaviour.  相似文献   
50.
In this study, effect of indium incorporation on the optical properties is investigated for the spray pyrolyzed onto glass substrates at 275°C substrate temperature undoped and indium doped Cd0.22Zn0.78S thin films. The average optical transmittance of all the films was over 77% in the wavelength range between 450 and 800 nm. The optical band gap energies of the thin films have been investigated by the measurement of the optical absorbance as a function of wavelength. The optical absorption studies reveal that the transitions are direct band gaps of 3.02 and 3.05 eV for undoped and doped indium Cd0.22Zn0.78S thin films, respectively. The Urbach tail parameter and optical constants such as refractive index, extinction coefficient, and dielectric constants were calculated for these films. The dispersion parameters such as single-oscillator energy and dispersive energy were discussed in terms oft he single-oscillator Wemple—DiDomenico model.  相似文献   
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