Evaluating optimal capacity of a single track is vital where decisions on investments are involved. The JNR have developed an experimental timetabling system using a computer complex in order to be able to operate a larger number of trains and stations and to plan timetable with greater precision. The results were put into practice for the first time in October 1978.
Cancellation carriers (CCs) are known to be effective for suppressing the out-of-band (OOB) spectrum of an orthogonal frequency-division multiplexing (OFDM) signal and are useful to realize OFDM-based overlay systems. We show that the known minimum-mean-square-error (MMSE) algorithm is not sufficient to reduced the OOB spectral peaks in the vicinity of transmission band boundaries compared to a direct minmax algorithm and show that a weighted MMSE (WMMSE) algorithm can attain almost the same suppression performance as the direct min-max algorithm with the same computational cost as the MMSE algorithm.
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Road network performance when a large disaster happens depends on how the road traffic is regulated. To evaluate the performance of the road network, one should consider the traffic regulation in an emergent condition. Authors have proposed the idea of area traffic regulation when a large disaster occurs (Iida, et al., 2000). In the former paper, a bi-level optimisation model to calculate the optimal regulation ratio is proposed. This paper proposes an efficient and fast method to calculate regulation ratios for two-stage road traffic regulation. The simplified model adopts linear programming method instead of bi-level optimisation method, which is quicker and simpler. The simpler algorithm contributes to conduct various kinds of case studies, and helps finding a reliability of the road network considering traffic regulations after a disaster.
In this study we proposed two Quasi-Newton methods to deal with traffic assignment in the capacitated network. The methods combine Newton formula, column generation and penalty techniques. The first method employ the gradient of the objective function to obtain an improving feasible direction scaled by the second-order derivatives. The second one is to employ Rosen gradient to obtain an improving direction scaled by the corresponding origin-destination demand. Both methods make line search to obtain an optimal step size to guarantee feasibility of either path or link flow. The proposed methods are of fast convergence and high accuracy at the expense of saving path information. Numerical examples verify their efficiency and stability, as well as usefulness of the path flow pattern reserved. The Quasi-Newton method with straight gradient demonstrates more stability than that with Rosen gradient for capacitated traffic assignment.
Abdominal aortic aneurysm (AAA), if left untreated, poses the main risks of progressive expansion, rupture, and hemorrhage, leading to death. Large AAA with a risk of rupture is usually treated by graft replacement or endovascular aneurysm repair. Nonsurgical treatment is not an alternative for large AAA, but is potentially beneficial for small AAA which usually requires a watchful waiting approach with medication.We introduce current clinical research regarding the pharmacological treatment of small AAA and assess the optimal time for starting the treatment.Data from current clinical researches on pharmacological treatment of AAA investigating the efficacy of pharmacological treatment to limit AAA growth were presented and introduced the medicines currently evaluated by randomized controlled trials for their efficacy for AAA.The optimal time to administer pharmacological treatment for AAA is during the stage wherein its diameter is still small. To detect early small-diameter AAA, screening tests are mandatory in high-risk patients. For pharmacological treatment, the drug that shows acceptable results in clinical tests and is the most effective for the patient's condition should be carefully selected. Lifestyle changes should also accompany pharmacological treatment.
