An algorithm is proposed for a music transcription system that displays notes and rests on a music staff. It is able to process multivoice music, which includes chords and counterpoint. The system first projects the sound onto the time-frequency plane by applying the Gabor wavelet transform, and then identifies tempo and duration by autocorrelation of the projection. Next, it uses the fundamental frequencies of simultaneously played tones to estimate the note. A state estimation technique is used to handle instrument-dependent harmonics.
Cycle slips in Global Navigation Satellite System (GNSS) signal tracking are significant error sources for carrier phase based GNSS applications, therefore it is necessary to detect and correct them. In this paper, we propose cycle slip detection and correction methods with time-differenced carrier phase measurements for single frequency applications. A time-differential technique is applied to cancel the integer ambiguities, but any cycle slips remain in the time-differenced carrier phase measurements. Two kinds of statistical hypothesis tests using the residuals in the least squares adjustment are adopted to detect cycle slips. We have evaluated the performance of our proposed methods with real receiver data for different time intervals. Finally, we show the results of cycle slip detection and correction tests by using our proposed methods for real receiver data with artificially added cycle slips in static and kinematic cases. Performance evaluation results show that our proposed methods can detect and correct cycle slips efficiently in both static and kinematic cases within 20-second data gaps. These results show that our proposed methods are promising for single frequency applications to achieve accurate and reliable cycle slip detection and correction performance comparable to those for dual frequency applications.
In this paper, the multi-layer ionospheric model based regional VTEC (Vertical Total Electron Content) estimation methods applied by GNSS (Global Navigation Satellite System) Regressive models (abbreviated as GR models) are presented. In the methods, the SCHA (Spherical Cap Harmonic Analysis) as well as the SHF (Spherical Harmonic Functions) are also applied to model the regional VTEC distributions. The ionospheric delays (or advances) over Japan are estimated by using GEONET (Gps Earth Observation NETwork) data provided from the GSI (Geospatial Information Authority of Japan). By applying the ionospheric correction based on the multi-layer model, the positioning accuracy can be improved, and consequently the regional ionosphere can be modeled more accurately by the multi-layer model.
Open-ended evolution is considered to be caused by several factors, one of which would be co-evolution. Competitive co-evolution can give rise to the “Red Queen effect”, where the fitness landscape of each population is continuously changed by the competing population. Therefore, if such continuous changes are captured, co-evolutionary progress would be measured. In this paper, we estimate features of competitive co-evolutionary fitness landscapes on a predator-prey problem in computer simulations and investigate the Red Queen effect on the fitness landscape. Two types of method were proposed to estimate features, ruggedness and neutrality. One was calculated based on accumulated data so far at each generation, and the other was based on accumulated data during a certain period. The results suggest to us that our method can track the progress of fitness landscapes on competitive co-evolutionary robotics.
In this paper, we consider an optimization problem with complementarity constraints and second-order cone constraints. The mathematical program with complementarity constraints (MPCC) has extensively been studied because MPCC has wide application such as engineering design, traffic equilibrium and game theory. Recently, second-order cone programming has also been studied intensively in relation to robust optimization under uncertainty. To the author’s knowledge, however, theoretical and algorithmic results about problems that contain both complementarity and second-order cone constraints have yet to be reported. In this paper, we propose a method for solving nonlinear second-order cone programs with complementarity constraints, which uses a smoothing technique to deal with complementarity constraints, and show its convergence. Moreover, as an application, we formulate a mathematical model of smart house scheduling as a nonlinear second-order cone program with complementarity constraints, and give numerical results with the proposed method.
This paper is concerned with the stability and H∞ performance analysis of discrete-time positive systems. In the literature, it is shown that the stability and H∞ performance of continuous-time positive systems can be characterized by LMIs with diagonal Lyapunov matrices. Recently, new LMIs allowing asymmetric matrix solutions have been reported as well. In this paper, by means of the Perron-Frobenius theorem, we first show that the Schur stability of a given positive matrix is equivalent to the Hurwitz stability of an appropriately constructed Metzler matrix. Then, we secondly prove that we can construct a continuous-time positive system preserving the stability and H∞ norm of the original discrete-time positive system. By applying existing results to the resulting continuous-time positive systems, we can readily obtain useful LMIs for the stability and H∞ performance analysis of discrete-time positive systems.