11 results match your criteria: "Kochi National College of Technology[Affiliation]"

We consider the problem of (stationary and linear) source systems which generate time series data with long-range correlations. We use the discrete Fourier transform (DFT) and build stationary linear models using artificial time series data exhibiting a 1/f spectrum, where the models can include only terms that contribute significantly to the model as assessed by information criteria. The result is that the optimal (best) model is only composed of mixed periodicities [that is, the model does not include all (continuous) periodicities] and the time series data generated by the model exhibit a clear 1/f spectrum in a wide frequency range.

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Substrate switchable Suzuki-Miyaura coupling for benzyl ester benzyl halide.

RSC Adv

October 2018

School of Environmental Science and Engineering, Kochi University of Technology Miyanokuchi, Tosayamada Kami Kochi 782-8502 Japan

Two reaction conditions were developed to accomplish the substrate switchable Suzuki-Miyaura coupling of benzyl derivatives and arylboronic acid derivatives. Under conditions for esters, benzyl esters such as carbonates and acetates reacted with arylboronic acids to afford the corresponding diarylmethanes. However, the benzyl halides did not react under the same conditions.

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Selective Synthesis of (Benzyl)biphenyls by Successive Suzuki-Miyaura Coupling of Phenylboronic Acids with 4-Bromobenzyl Acetate under Air Atmosphere.

ACS Omega

November 2017

School of Environmental Science and Engineering and Research Center for Material Science and Engineering, Kochi University of Technology, Tosayamada, Kami, Kochi 782-8502, Japan.

An efficient Pd-catalyzed cross-coupling reaction of phenylboronic acids and benzyl carbonates was developed, producing diarylmethanes. Benzyl acetates could also be used as coupling partners instead of benzyl carbonates, affording diarylmethanes in comparable yields. This reaction can be conducted under air atmosphere without any care for moisture and oxygen.

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We present an exact analysis of the physical properties of bimodal networks specified by the two peak degree distribution fully incorporating the degree-degree correlation between node connections. The structure of the correlated bimodal network is uniquely determined by the Pearson coefficient of the degree correlation, keeping its degree distribution fixed. The percolation threshold and the giant component fraction of the correlated bimodal network are analytically calculated in the whole range of the Pearson coefficient from -1 to 1 against two major types of node removal, which are the random failure and the degree-based targeted attack.

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We describe a method for constructing networks for multivariate nonlinear time series. We approach the interaction between the various scalar time series from a deterministic dynamical system perspective and provide a generic and algorithmic test for whether the interaction between two measured time series is statistically significant. The method can be applied even when the data exhibit no obvious qualitative similarity: a situation in which the naive method utilizing the cross correlation function directly cannot correctly identify connectivity.

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Robustness of cooperation on scale-free networks under continuous topological change.

Phys Rev E Stat Nonlin Soft Matter Phys

November 2013

Department of Electrical Engineering and Information Science, Kochi National College of Technology, 200-1 Monobe-Otsu, Nankoku, Kochi 783-8508, Japan.

In this paper, we numerically investigate the robustness of cooperation clusters in prisoner's dilemma played on scale-free networks, where the network topologies change by continuous removal and addition of nodes. Each removal and addition can be either random or intentional. We therefore have four different strategies in changing network topology: random removal and random addition (RR), random removal and preferential addition (RP), targeted removal and random addition (TR), and targeted removal and preferential addition (TP).

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Note: Human heartbeat measurement on the basis of current generated by electrostatic induction.

Rev Sci Instrum

February 2011

Department of Electrical Engineering and Information Science, Kochi National College of Technology, Nankoku-shi, Kochi, Japan.

In this study, we developed an effective nonattached, noncontact technique for measurement of the human heartbeat. This method detects the human heartbeat by measuring the current generated by variations in the capacitance between a given electrode and the human body. An electrode is placed a few centimeters from the subject's chest, and the electrostatic induction current (on the order of picoamperes) flowing through the electrode is then detected.

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The immobilization conditions of commercial ketoreductase for continuous enantioselective reduction in the gas-phase reaction were investigated with respect to the immobilization efficiency (residual activity and protein loading) and the gas-phase reaction efficiency (initial reaction rate, half-life, and enantioselectivity). For the analyses, ketoreductase was first immobilized by physical deposition on glass supports and the reduction of 2-butanone to (S)-2-butanol with the concomitant regeneration of NADH by 2-propanol was used as a model reaction. The optimal conditions of enzyme immobilization were obtained using an absolute pressure of 100 hPa for drying, a pH between 6.

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Optimization of the robustness of multimodal networks.

Phys Rev E Stat Nonlin Soft Matter Phys

July 2006

Kochi National College of Technology, Monobe-Otsu 200-1, Nankoku, Kochi 783-8508, Japan.

We investigate the robustness against both random and targeted node removal of networks in which P(k), the distribution of nodes with degree k, is a multimodal distribution, [formula--see text] with k(i) proportional to b -(i-1) and Dirac's delta function delta (x). We refer to this type of network as a scale-free multimodal network. For m=2, the network is a bimodal network; in the limit m approaches infinity, the network models a scale-free network.

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Interesterification activity of Rhizopus delemar lipase in phospholipid microemulsions.

Colloids Surf B Biointerfaces

November 2004

Department of Materials Science and Engineering, Kochi National College of Technology, 200-1 Monobe, Nankoku, Kochi 783-8508, Japan.

The interesterification of olive oil with palmitic acid catalyzed by Rhizopus delemar lipase was investigated in phospholipid microemulsion systems. Soybean lecithin was used as the amphiphilic component. The maximal reaction rate was obtained at a buffer pH of 5.

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