2,863 research outputs found
Global fitness profiling of fission yeast deletion strains by barcode sequencing
A genome-wide deletion library is a powerful tool for probing gene functions and one has recently become available for the fission yeast Schizosaccharomyces pombe. Here we use deep sequencing to accurately characterize the barcode sequences in the deletion library, thus enabling the quantitative measurement of the fitness of fission yeast deletion strains by barcode sequencing
Wiener–Khinchin Theorem in a Reverberation Chamber
IEEE The use of the Wiener–Khinchin theorem in the reverberation chamber reveals the relationships between a number of important parameters—the coherence bandwidth and the Q-factor measured in the time domain, the coherence time and the Q-factor measured in the frequency domain, the K-factor and the Doppler spectrum, and the K-factor and the total scattering cross section. The lower bound of the average K-factor is also given. Different physical quantities, which share similar mathematical insights, are unified. Analytical derivations are given, and results are validated by measurements
Two types of generalized integrable decompositions and new solitary-wave solutions for the modified Kadomtsev-Petviashvili equation with symbolic computation
The modified Kadomtsev-Petviashvili (mKP) equation is shown in this paper to
be decomposable into the first two soliton equations of the 2N-coupled
Chen-Lee-Liu and Kaup-Newell hierarchies by respectively nonlinearizing two
sets of symmetry Lax pairs. In these two cases, the decomposed
(1+1)-dimensional nonlinear systems both have a couple of different Lax
representations, which means that there are two linear systems associated with
the mKP equation under the same constraint between the potential and
eigenfunctions. For each Lax representation of the decomposed (1+1)-dimensional
nonlinear systems, the corresponding Darboux transformation is further
constructed such that a series of explicit solutions of the mKP equation can be
recursively generated with the assistance of symbolic computation. In
illustration, four new families of solitary-wave solutions are presented and
the relevant stability is analyzed.Comment: 23 page
MOQPSO-D/S for Air and Missile Defense WTA Problem under Uncertainty
Aiming at the shortcomings of single objective optimization for solving weapon target assignment (WTA) and the existing multiobjective optimization based WTA method having problems being applied in air and missile defense combat under uncertainty, a fuzzy multiobjective programming based WTA method was proposed to enhance the adaptability of WTA decision to the changes of battlefield situation. Firstly, a multiobjective quantum-behaved particle swarm optimization with double/single-well (MOQPSO-D/S) algorithm was proposed by adopting the double/single-well based position update method, the hybrid random mutation method, and the two-stage based guider particles selection method. Secondly, a fuzzy multiobjective programming WTA model was constructed with consideration of air and missile defense combat’s characteristics. And, the uncertain WTA model was equivalently clarified based on the necessity degree principle of uncertainty theory. Thirdly, with particles encoding and illegal particles adjusting, the MOQPSO-D/S algorithm was adopted to solve the fuzzy multiobjective programming based WTA model. Finally, example simulation was conducted, and the result shows that the WTA model constructed is rational and MOQPSO-D/S algorithm is efficient
A Fast Method to Measure the Volume of a Large Cavity
How to quickly and accurately measure the volume of a large cavity is challenging. This paper presents an efficient method to measure the volume of a large conducting cavity. The proposed method is based on statistical wave theory. By measuring the Q factor in the time and frequency domains, the volume of the cavity can be extracted. In the time domain, the Q factor can be extracted directly from the time domain response, while in the frequency domain, the Q factor depends on the volume of the cavity and the transferred power; the transferred power can be measured directly. By correcting the frequency domain Q with the radiation efficiency of antennas, the Q factors obtained from both the time and frequency domains are equal in a well-stirred chamber; this provides an opportunity to measure the volume of the cavity. Measurements are conducted to verify the proposed method. Although the measurement is conducted using electromagnetic waves, acoustic waves can also be used; in this case, the approach can be applied to any cavity, not limited to a conducting cavity. The advantages and the limitations of the proposed method are also discussed
B-Scan in a Reverberation Chamber
In this paper, the B-scan technique is applied to a reverberation chamber (RC) for the first time to characterize the time-domain behavior of the chamber. Based on B-scan measurement results, three things are studied in this paper. 1) The statistical behavior of the fields in the time domain is investigated, and it is found that the received power of the impulse response follows chi-square distribution with one degree of freedom. 2) The stirrer efficiency is quantified based on the equivalent total scattering cross section (TSCS) of stirrers, and this definition is not sensitive to the antenna position and load in the RC. It is shown that the stirrer efficiency defined in this paper provides, for the first time, a quantitative way to evaluate the stirrer design and the chamber performance. 3) A time-gating technique is proposed which provides an alternative method to eliminate the early time response and obtain the chamber transfer function of the RC accurately. This could be potentially used to increase the stirrer efficiency without changing the stirrers physically. It is demonstrated that the B-scan technique is a very useful approach for the study and evaluation of an RC
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