Analysis of the infinite array of slot impedance loads based on the cavity with an equilateral triangular cross section
Two-dimensional problem of an infinite array of slot impedance loads by the plane wave is considered. Each array element represents a slot in a perfectly conducting screen loaded by a cavity with equilateral triangle cross-section. The integral equations method is used to solve the problem, the Krylov-Bogoliubov method is applied to calculate them. For the case of H-polarized incident wave equivalent surface impedance dependencies on construction geometric sizes is calculated. Comparative analysis of dependencies obtained for construction under consideration of an infinite array of slot impedance loads with those ones for single impedance load is carried on.
Backscattering from an impedance loaded slotted cylinder
When a thick infinite cylinder is illuminated by a plane wave with a perpendicular electric field at normal incidence, its backscattering can be controlled by implementing an impedanced-backed longitudinal slot on its surface. An exact theory is developed to account for the scattered field from an impedance loaded slotted cylinder. Optimum slot loadings for minimizing and maximizing the backscattering from the cylinder are determined. A series of experiments has been conducted to verify the theory. Excellent agreement between theory and experiment is obtained. The present study indicates that a very effective reduction in the backscattering from the cylinder can be achieved by a proper design of the slot loading.
Avocado Flowering 1
The avocado (Persea americana Mill.) has increased in importance over the years in many countries around the world. The United States, Mexico and Brazil lead in world commercial production, while Israel, South Africa, Australia, New Zealand, the Philippines, Spain, Cyprus, Canary Islands, Chile, Ecuador, Venezuela, Greece, and the Caribbean area are actively increasing commercial production (B.O. Bergh, personal communication; Gustafson 1976). The history of the avocado has been detailed by Gustafson (1973, 1975,1976) and others (Bergh 1975b, Knight 1980; Popenoe 1924; Ruehle 1958; Schroeder 1958; Williams 1976). Several reviews have been published on various aspects of the avocado, including its botany (Knight 1980; Purseglove 1968; Williams 1976), breeding (Bergh 1975b), horticulture (Hodgson 1930b; Ruehle 1958; Ryerson et al. 1924), cultivars (Campbell and Malo 1976), and pollination (Gustafson and Bergh 1966). A recent collection of papers discussing the horticultural aspects of avocado production is found in Sauls et al. (1976).