Balanced Ring Research Articles

An Ultra-Broadband Doubly Balanced Monolithic Ring Mixer for Ku- to Ka-band Applications

A novel 12-40 GHz ultra-broadband doubly balanced monolithic ring mixer with a small chip size covering the Ku- to Ka-band applications implemented by a 0.15-mum pseudo- morphic high electron-mobility transistor process is presented. The proposed mixer consists of two spiral transformer baluns and a band-reject filter. The use of the spiral baluns leads to the achievement of a chip size less than 0.8 times 0.8 mm2. The radio frequency (RF) spiral balun with a band-reject filter served by an L-C resonator is used to improve the bandwidth of the mixer and to provide an output port for the intermediate frequency (IF) extraction as well. The mixer exhibits a 6-12 dB conversion loss, high isolation over 12-40 GHz RF/local oscillation bandwidth, a DC-8 GHz IF bandwidth, and a 1-dB compression power of 14 dBm for both down- and up-converter applications.

Enhanced fault tolerant routing algorithms using a concept of “balanced ring”

Fault rings can be used to guide messages bypass faulty nodes/links in a fault tolerant interconnection network. However, nodes on the fault ring become hot spots, thus causing uneven distribution of the traffic loads. To avoid such traffic congestion, a concept of the balanced ring is proposed in this paper. The proposed balanced ring, defined as concentric rings of a given fault ring, can be applied to the fault tolerant routing algorithms for mesh and torus topologies. By properly guiding messages to route on the balanced ring and the fault ring, more balanced link utilization and greatly reduced traffic congestion can be achieved on a fault tolerant network. Methods of applying the balanced ring concept to some published fault tolerant routing algorithms are discussed. Proof of deadlock and livelock freedom is also presented. The use of balanced ring does not need to add new virtual channels. The performance of two routing algorithms with and without the balanced ring is simulated and evaluated. The results indicate that routing algorithms with the balanced rings constantly yield larger throughput and smaller latency than those without.

Redefining monosomy 5 by molecular cytogenetics in 23 patients with MDS/AML

Deletion of the long arm of chromosome 5 [del(5q)] or loss of a whole chromosome 5 (-5) is a common finding, arising de novo in 10% of patients with myelodysplastic syndromes (MDS) or acute myeloid leukemia (AML) and in 40% of patients with therapy-related MDS or AML. We investigated by molecular cytogenetics 23 MDS/AML patients for whom conventional cytogenetics detected a monosomy 5. Monosomy 5 was redefined as unbalanced or balanced translocation and ring of chromosome 5. Loss of 5q material was identified in all 23 patients, but one. One copy of EGR1(5q31) or CSF1R(5q33-34) genes was lost in 22 of the 23 patients. Chromosome 5p material was a constant chromosomal component of derivative chromosomes or rings in all patients, but one. Sequential fluorescent in situ hybridization studies with whole chromosome paints and region-specific probes, used as a complement to conventional cytogenetic analysis, allow a better interpretation of karyotypes in MDS/AML patients.

Design of microstrip resonators using balanced and unbalanced composite right/left-handed transmission lines

Balanced and unbalanced composite right/left-handed transmission lines are used in the design of resonators. The balanced resonator is designed by changing the nonlinear phase response in order to control the spacing between modes and the Q factor. Two balanced ring resonators are measured and one demonstrates increased mode spacing/decreased Q factor and the other demonstrates decreased mode spacing/increased loaded Q factor. The unbalanced resonator is designed by changing the nonlinear phase response and magnitude response. A measured unbalanced ring resonator shows increased mode spacing with a reasonable Q factor. A microstrip line resonator is measured to demonstrate higher frequency capabilities.

Measurement of induced birefringence in film samples using a balanced polarization ring interferometer

A new method for measuring the induced birefringence due to e.g. the electro-optic response of film samples is proposed, described and verified experimentally. The method uses a polarization ring interferometer which allows for the total cancellation of the residual dichroism and birefringence of the apparatus and of the sample. The method is ideally suited for modulation measurements and frequency analysis of the electro-optic response.

Balanced modules and rings of left colocal type

is a ring homomorphism, where rm is the left multiplication of r, i.e., rm(x)= rx for all x^M. If p is surjective, or equivalently every element of BiEndG?M) is a left multiplication of an element of R, then M is said to be balanced. If every finitely generated faithfulleft i?-module is balanced, then R is called a left QF-l ring. Further, R is said to be a left balanced ring if R/l is left QF-l for every two sided ideal / of R; this condition is equivalent to the condition that every finitelygenerated left module is balanced. The concept of QF-l rings was introduced by Thrall [18] as a generalization of quasi-Frobenius rings, and in the same paper he proposed to give an internal characterization of QF-l rings. At the present time, however, this problem is not solved completely, though partial answers are given in several cases (Camillo and Fuller [1], Dlab and Ringel [2], Fuller [7], Makino [8, 9, 10], Morita [11], Ringel [12] and Tachikawa [17]). On the other hand, the structure of balanced rings was completely determined by Dlab and Ringel [2, 3, 4, 5, 6]. Indeed they proved that an indecomposable ring is left balanced if and only if it is a full matrix ring over either a local uniserial ring or an exceptional ring. We should note that exceptional rings are characterized as local rings of either left or right colocal type with the square zero radical (see Section 1 for the precise definition of rings of left colocal type). Our aim of this paper is to show that in the case of left serial rings, left QF-lness, which is much more weaker condition than left balancedness, implies rings of left colocal tvoe (Theorem). For the case of a finite dimensional

Diode characteristics and edge effects of metal-semiconductor diodes

When investigating metal-semiconductor barriers, measured I– V-characteristics are often used for deducing barrier height, origin of current components etc. This paper discusses under what conditions errors may be caused by edge-generated currents, and the influence of guard rings is investigated. The system studied was gold on chemically prepared silicon. Investigating reverse characteristics, it was shown that, for diodes having diameters of a few mm, edge effects are important when the silicon resistivity is ≳ 100 Ω cm , but negligible for lower ϱ. Diodes with no guard rings (NGR) had currents several times those surrounded by rings held at the same voltage (balanced guard ring, BGR), at low voltages, and the excess increased with voltage. Studies of activation curves for the current revealed that the current in the BGR case essentially obeyed a Schottky barrier expression (barrier height 0·75–0·80 V) while NGR curves showed appreciably smaller activation energies, indicating contribution of surface- and volume-generated currents at the edge. For diodes of low resistivity avalanche effects are important at high voltages. The main features of the current variation with voltage for higher resistivity BGR diodes (up to 30 kΩ cm ) are in agreement with the image-force lowering effect and the influence of bulk generation current.

Balanced Rings and a Problem of Thrall

Balanced ring is defined and related to Thrall’s QF-1 rings. Several theorems are obtained which show that balanced rings enjoy strong homological and chain conditions. The structure of commutative balanced rings is determined. Also, the structure of commutative artinian QF-1 rings is gotten. This is a generalization of a theorem of Floyd.

Balanced rings and a problem of Thrall

Balanced ring is defined and related to Thrall’s QF-1 rings. Several theorems are obtained which show that balanced rings enjoy strong homological and chain conditions. The structure of commutative balanced rings is determined. Also, the structure of commutative artinian QF-1 rings is gotten. This is a generalization of a theorem of Floyd.