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Transparent photonic band in metallodielectric nanostructures
Under certain conditions, a transparent photonic band can be designed into a
one-dimensional metallodielectric nanofilm structure. Unlike conventional pass
bands in photonic crystals, where the finite thickness of the structure affects
the transmission of electromagnetic fields having frequency within the pass
band, the properties of the transparent band are almost unaffected by the
finite thickness of the structure. In other words, an incident field at a
frequency within the transparent band exhibits 100% transmission independent of
the number of periods of the structure. The transparent photonic band
corresponds to excitation of pure eigenstate modes across the entire Bloch band
in structures possessing mirror symmetry. The conditions to create these modes
and thereby to lead to a totally transparent band phenomenon are discussed.Comment: To be published in Phys. Rev.
Characteristics of bound modes in coupled dielectric waveguides containing negative index media
We investigate the characteristics of guided wave modes in planar coupled
waveguides. In particular, we calculate the dispersion relations for TM modes
in which one or both of the guiding layers consists of negative index media
(NIM)-where the permittivity and permeability are both negative. We find that
the Poynting vector within the NIM waveguide axis can change sign and
magnitude, a feature that is reflected in the dispersion curves
Local well-posedness and blow up in the energy space for a class of L2 critical dispersion generalized Benjamin-Ono equations
We consider a family of dispersion generalized Benjamin-Ono equations (dgBO)
which are critical with respect to the L2 norm and interpolate between the
critical modified (BO) equation and the critical generalized Korteweg-de Vries
equation (gKdV). First, we prove local well-posedness in the energy space for
these equations, extending results by Kenig, Ponce and Vega concerning the
(gKdV) equations. Second, we address the blow up problem in the spirit of works
of Martel and Merle on the critical (gKdV) equation, by studying rigidity
properties of the (dgBO) flow in a neighborhood of solitons. We prove that when
the model is close to critical (gKdV), solutions of negative energy close to
solitons blow up in finite or infinite time in the energy space. The blow up
proof requires in particular extensions to (dgBO) of monotonicity results for
localized versions of L2 norms by pseudo-differential operator tools.Comment: Submitte
An analysis of the alumni relations program of Heston College and Bible School.
Thesis (M.S.)--Boston Universit
Legislation—The Effect of Motor Vehicle Registration Statutes on Security Transactions and Recordations
Changes in Cardiovascular Condition Resulting from an Eight Week Training Program as Shown by the Cameron Heartometer
The effect of different activities and conditioning exercises on the cardiovascular system has been the basis for many recent studies by physical educators and physiologists. No doubt much of this research has been prompted by statements such as that by Reidman, “An athlete is only as good as his heart.” Reidman reasoned that the ability of the athlete to perform work was dependent in large measure on the ability of the heart to supply oxygen to the muscles. This, in turn, was dependent upon two factors: (1) the capacity of exertion, and (2) the ability of the heart to return to its resting pulse state. Other students of physiology have indicated that there is a great need for methods by which people may be motivated to maintain sound cardiovascular fitness. The number of deaths attributed to diseases of the heart and cardiovascular system have certainly emphasized the truth and importance of such statements. It should be the obligation of physical educators and physiologists to determine which activities best serve to condition the heart and circulatory system and to develop within their students a feeling of “need” for cardiovascular fitness. It was with these thoughts in mind that the author decided to pursue further the problem of cardiovascular condition resulting from certain types of exercise. Weight training has recently been widely accepted by coaches and physical educators as a means to improve the strength and physiological condition of their athletes and students. Since cardiovascular fitness is an important part of total physiological fitness and has a direct bearing on individual motor performance there seemed to be a need for a study of relationship between weight training and cardiovascular condition. The purpose of this study was to identify and analyze changes in cardiovascular condition resulting from an eight week progressive weight training program. Subjects were 37 South Dakota State College freshmen male students who were enrolled in weight training classes. Steps in the solution of this problem were: (1) To graphically record, both before and after the period of training, the heart action at rest and after a brief exertive exercise. (2) To determine, both before and after the period of training, the pulse rate, the systolic pulse wave amplitude, the diastolic pulse wave amplitude, the dicrotic notch amplitude and the diastolic surge of each subject at rest and following a brief exertive exercise. (3) TO measure the body weight of each subject before and after the training period. (4) To compute the fatigue ratio, recovery indices, and weight indices of the subjects before and after the training period. (5) To calculate the difference and the significance of the differences between the means of the subjects’ test data before they began weight training and the means of their data after the training. (6) To determine by correlative techniques any significant relationships between several of the test variables in this study
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