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81.
82.
Vishal Kesari P. K. Jain B. N. Basu 《International Journal of Infrared and Millimeter Waves》2007,28(6):443-449
In the method of tapering the cross section of the interaction structure for broadbanding a gyro-TWT, the different portions
of the interaction length of the tapered-cross-section waveguide become effective for different frequency ranges if the magnetic
field and beam parameters are profiled to maintain the condition of electron cyclotron resonance throughout the interaction
length. In the present paper, the study of profiling the magnetic field and beam parameters in steps of the stepped analytical
model of a double-tapered disc-loaded circular waveguide was made throughout the steps of the model. In the observed profile,
the magnetic flux density in a typical step relative to its value in first-step decreases from first-step (gun-end) to end-step
(collector-end) of the model considering the up-tapering schemes, in which structure parameters increase from gun-end to collector-end.
Also, the transverse beam velocity in a typical step relative to its value in first-step decreases from gun-end to collector-end.
However, the Larmor radius in a typical step relative to its value in first-step as well as the hollow-beam radius in a typical
step relative to its value in first-step, both increase from gun-end to collector-end in the model considering the up-tapering
schemes. 相似文献
83.
The mixing of the glueball candidate?i(1,460) with η and η′ is studied in a chiral symmetry breaking framework. Using the solutions of anomalous Ward identities for flavourU(3)×U(3), we find that the octet-singlet mixing angle is quite large and that our results are consistent with a large glueball component in?i(1,460) with moderate gluonium mixing in η and η′. 相似文献
84.
Sumit Saha 《Tetrahedron letters》2008,49(41):5928-5930
A mild and efficient method for the preparation of acetonides from epoxides catalyzed by iron(III) chlorides has been developed. 相似文献
85.
In this Letter, we describe the novel synthetic approach to the tricyclic core of (±)-galanthamine from the easily available starting material isovanillin. 相似文献
86.
Asis Basu 《Annals of Physics》2005,319(2):274-285
The enveloping algebra, Dn, of fermions is extended on the lattice to include the discrete space invariance. This extended algebra, denoted X, has the space symmetry as a factor: X/Dn = space group. 相似文献
87.
This paper addresses the problem of scheduling cascaded ‘blocked out’ continuous processing units separated by finite capacity
storage tanks. The raw materials for the product lines arrive simultaneously on the input side of the first unit. But every
unit can process only one product line at a time, thus giving rise to the possibility of spillage of raw material due to limited
storage capacity. The need to process multiple product lines and the added constraint of multiple intermediate upliftment
dates aggravate the problem. This problem is quite common in petrochemical industry. The paper provides a MINLP (Mixed Integer
Non-Linear Programming) formulation of the problem. However, for any realistic scheduling horizon, the size of the problem
is too large to be solved by standard packages. We have proposed a depth first branch and bound algorithm, guided by heuristics,
to help planners in tackling the problem. The suggested algorithm could output near optimal solutions for scheduling horizons
of 30 time periods when applied to real life situations involving 3 units and 3 product lines.
Preliminary version of the paper appeared in the proceedings of MISTA, 2005. 相似文献
88.
89.
90.
Birefringent filters can be used for tuning lasers, with some advantages over prisms, gratings and tilted etalons. In this paper the transmission characteristics of a new mixed birefringent filter are investigated. The term ‘mixed’ is used because both circular birefringence and linear birefringence have been utilized in the fabrication of this filter.It has a loss-less core, formed by a cascaded system of alternate rotators and retarders, and a linear polarizer at each end. The performance of this filter is better because of the more effective suppression of side peaks. Unlike previous birefringent filters, this one may be used inside a linear resonator. 相似文献