In this paper, a novel threshold selection algorithm for the 60 GHz TOA (time of arrival) estimation is proposed. It exploits the skewness, kurtosis, standard deviation and curl of the received (Energy Detector) ED based samples. The best threshold values for different signal to noise ratio (SNR) are investigated via simulations. The proposed ED based technique has low complexity, sampling rate requirements, and high accuracy compared with other ED based algorithms.

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Until now, we have studied for the method of the statistical pattern recognition based on auto-regressive (AR) model for the purpose of identifying the EEG signals during motor imagery. The statistical pattern recognition of the EEG signals during three motor imagery (left hand, right hand and right foot) were performed by using the method. As a result, we confirmed that subjects became to able to handle a robot with about a 10 days training. Though, some of subjects were confused to this system since the training system was composed by previous time experiment that included noise element. In this paper, the robust method was introduced to estimate parameter in order to construct more stable BCI system.

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In performing the program operation of the NAND-type flash memory array, the program-inhibited cell is applied by a positive voltage at the gate, i.e., word-line (WL) on the floating channel while the program cell is applied by program voltage as the two ends, drain select line (DSL) and source select line (SSL), are turned on with grounded bit-line (BL). In this manner, the self-boosting of silicon channel to avoid unwanted program operation is made possible. As the flash memory device is aggressively scaled down and the channel doping concentration is increased accordingly, the coupling phenomena among WL, floating gate (FG)/storage node, and silicon channel, which are crucial factors in the self-boosting scheme, should be investigated more thoroughly. In this work, the dependences of self-boosting of channel potential on channel length and doping concentration in the 2-D conventional planar and 3-D FinFET NAND-type flash memory devices based on bulk-silicon are investigated by both 2-D and 3-D numerical device simulations. Since there hardly exists realistic ways of measuring the channel potential by physical probing, the series of simulation works are believed to offer practical insights in the variation of channel potential inside a flash memory device.

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This paper proposes a multiple code block transmission scheme using hierarchical modulation (HM) for a broadcast channel in the orthogonal frequency division multiplexing (OFDM) downlink. We investigate the average bit error rate (BER) performance of two-layer HM using 16 quadrature amplitude modulation (QAM) and three-layer HM using 64QAM in multipath Rayleigh fading channels. In multiple code block transmission using HM, the basic information bits are demodulated and decoded to all users within a cell that satisfy the bit error rate (BER) requirement. Hence, we investigate non-uniform QAM constellations to find one that suppresses the loss in the average BER of the basic information bits for HM to a low level compared to that using the original constellation in which only the basic information bits are transmitted while simultaneously minimizing the loss in the average BER of the secondary and tertiary information bits from the original constellations in which the information bits of the respective layers are transmitted alone. Based on the path loss equations in the Urban Macro and Rural Macro scenarios, we also investigate the maximum distance from a base station (BS) for the information bits of each layer to attain the required average received signal-to-noise power ratio (SNR) that achieves the average BER of 10^-3.

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In this research, the flow field measurement around ship hull at incidence was made by using five hole Pitot Tube which was operated by automatic flow measuring system. At first, the paper describes the developed system for flow measurements in circulating water channel. The system is consist of two parts: the sensor controlling system, a kind of a robot manupulator, and the data acquisition system. The system enables measuring of flow velocity vector around ship model automatically using several microcomputers which are cominucated through RS232 . The results of flow field measurment around ship hull at incidence are shown, at whole of the back side region from fore to aft peak. The vortex separeted at fore part travels with the outer potntial flow. Therefore, the path line of the vortex is different from that of full ship as a tanker model.

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Wireless communications for the control of industrial equipments need to send a large amount of short packets frequently and to improve frame efficiency. The OFDM frame of wireless local area networks has short preambles that are used for timing synchronization and coarse frequency offset estimation. As the short preambles are repeated in a time domain, they occupies subcarriers intermittently. Therefore, in this paper, a new frame format with OFDM modulation in which data symbols are orthogonally multiplexed with the preamble symbols in the frequency domain is proposed. Two preamble sequences that are based on an IEEE802.11g short preamble sequence and a Zadoff-Chu sequence are examined. The ratio of transmission powers between the pilot subcarrier and the data subcarrier is also varied. The timing synchronization probability with those sequences has been evaluated on different channel models. It is shown through the experiment that the synchronization performance is almost the same as that without data multiplexing at E_s/N₀ of more than 8dB.

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The East Off Chiba Prefecture Earthquake occurred on December 17, 1987, was the first earthquake hazard attacked Tokyo Metropolitan area, since the 1923 Kanto Earthquake . Liquefaction phenomena occurred on the wide area, such as Kujyukuri plain, Tone -River lowland and Tokyo -Bay coastal area, comparing with the magnitude of the earthquake (M=6.7).

Authors investigated the liquefaction phenomena on Tokyo -Bay coastal reclamation area . As the reclaimed area have increased with high speed on the coast of Tokyo -Bay area, it is important for disaster prevention on coastal area to know the places where liquefaction phenomena occurred .

We mainly analyzed boring log data and interpreted aerial photograph. Since this earthquake was on the boundary line of the liquefaction phenomena due to this earthquake, this phenomena concentrated on undesirable geological condition. As the result of the investigation, liquefaction phenomena occurred on the following geological conditions.

1 Buried valley.

2 Fairway before reclamation.

3 Channel during reclamation work.

Common characteristic of these geological conditions is the existance of newly deposited thick sediment covering the ditch topography.

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Smart contracts are protocols that can automatically execute a transaction including an electronic contract when a condition is satisfied without a trusted third party. In a representative use-case, a smart contract is executed when multiple parties fairly trade on a blockchain asset. On blockchain systems, a smart contract can be regarded as a system participant, responding to the information received, receiving and storing values, and sending information and values outwards. Also, a smart contract can temporarily keep assets, and always perform operations in accordance with prior rules. Many cryptocurrencies have implemented smart contracts. At POST2018, Atzei et al. give formulations of seven fair exchange protocols using smart contract on Bitcoin: oracle, escrow, intermediated payment, timed commitment, micropayment channels, fair lotteries, and contingent payment. However, they only give an informal discussion on security. In this paper, we verify the fairness of their seven protocols by using the formal verification tool ProVerif. As a result, we show that five protocols (the oracle, intermediated payment, timed commitment, micropayment channels and fair lotteries protocols) satisfy fairness, which were not proved formally. Also, we re-find known attacks to break fairness of two protocols (the escrow and contingent payment protocols). For the escrow protocol, we formalize the two-party scheme and the three-party scheme with an arbitrator, and show that the two-party scheme does not satisfy fairness as Atzei et al. showed. For the contingent payment protocol, we formalize the protocol with the non-interactive zero-knowledge proof (NIZK), and re-find the attack shown by Campanelli et al. at CCS 2017. Also, we show that a countermeasure with subversion NIZK against the attack works properly while it is not formally proved.

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Let P be a subset of 2-dimensional integer lattice points P={1, 2, ..., m}×{1, 2, ..., n}⊆Z^2. We consider the graph G_P with vertex set P satisfying that two vertices in P are adjacent if and only if Euclidean distance between the pair is less than or equal to √<2>. Given a non-negative vertex weight vector ω∈Z^P_+, a multicoloring of (G_P, ω) is an assignment of colors to P such that each vertex υ∈P admits ω(υ) colors and every adjacent pair of two vertices does not share a common color. We show the NP-completeness of the problem to determine the existence of a multicoloring of (G_P, ω) with strictly less than (4/3)ω colors where ω denotes the weight of a maximum weight clique. We also propose an O(mn) time approximation algorithm for multicoloring (G_P, ω). Our algorithm finds a multicoloring with at most (4/3)ω+4 colors Our algorithm based on the property that when n=3, we can find a multicoloring of (G_P, ω) with ω colors easily, since an undirected graph associated with (G_P, ω) becomes a perfect graph.

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A strain difference was found in the pancreatic α-amylase in rat strains, Rattus norvegicus. This variation is under the genetic control of a single locus, Amy-1. The locus Amy-1 contains dominant and recessive alleles, Amy-1^a and Amy-1^b, which correspond to the positive and negative expression of the minor band, respectively. An electrophoretic survey of small intestine esterases showed a new phenotype controlled by Es-3 locus. Linkage tests showed 8.5% recombination frequency between Es-1 and Es-3 loci on linkage group V. Amy-1 and Es-1 loci did not belong to the same linkage group.

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In this paper, we focus on a centralized spectrum access strategy in a cognitive radio network, in which a single licensed spectrum with one primary user (PU) and several secondary users (SUs) (multiple input streams) are considered. We assume the spectrum can be divided into multiple channels and the packets from variable SUs can arrive at the system simultaneously. Taking into account the priority of the PU, we suppose that one PU packet can occupy the whole licensed spectrum, while one SU packet will occupy only one of the channels split from the licensed spectrum when that channel is not used. Moreover, in order to reduce the blocking ratio of the SUs, a buffer with finite capacity for the SUs is set. Regarding the packet arrivals from different SUs as multiple input streams, we build a two-dimensional Markov chain model based on the phase of the licensed spectrum and the number of SU packets in the buffer. Then we give the transition probability matrix for the Markov chain. Additionally, we analyze the system model in steady state and derive some important performance measures for the SUs, such as the average queue length in the buffer, the throughput and the blocking ratio. With the trade-off between different performance measures, we construct a net benefit function. At last, we provide numerical results to show the change trends of the performance measures with respect to the capacity of the SU buffer under different network conditions, and optimize the capacity of the SU buffer accordingly.

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LINE is currently the most popular messaging service in Japan. Communications using LINE are protected by the original encryption scheme, called LINE Encryption, and specifications of the client-to-server transport encryption protocol and the client-to-client message end-to-end encryption protocol are published by the Technical Whitepaper. Though a spoofing attack (i.e., a malicious client makes another client misunderstand the identity of the peer) and a reply attack (i.e., a message in a session is sent again in another session by a man-in-the-middle adversary, and the receiver accepts these messages) to the end-to-end protocol have been shown, no formal security analysis of these protocols is known. In this paper, we show a formal verification result of secrecy of application data and authenticity for protocols of LINE Encryption (Version 1.0) by using the automated security verification tool ProVerif. Especially, since it is claimed that the transport protocol satisfies forward secrecy (i.e., even if the static private key is leaked, security of application data is guaranteed), we verify forward secrecy for client's data and for server's data of the transport protocol, and we find an attack to break secrecy of client's application data. Moreover, we find the spoofing attack and the reply attack, which are reported in previous papers.

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Polydimethylsiloxane has been dominantly employed as the substrate material for microchip capillary electrophoresis. The poor surface chemistry, however, generates inconsistent electroosmotic flow under the electrophoretic condition, limiting its broader applications. In this work, different polyelectrolytes, including polydiallyldimethylammonium chloride, polyvinyl sulfate, and dextran sulfate, were successfully deposited onto polydimethylsiloxane microchannel surfaces. The polyelectrolyte coated polydimethylsiloxane microchannel showed improved consistency and reproducibility in electroosmotic flow under an electric field over the uncoated native microchannel.

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Air-segmentation is applied to amplitude-modulated multiplexed flow analysis, which we proposed recently. Sample solutions, the flow rates of which are varied periodically, are merged with reagent and/or diluent solution. The merged stream is segmented by air-bubbles and, downstream, its absorbance is measured after deaeration. The analytes in the samples are quantified from the amplitudes of the respective wave components in the absorbance. The proposed method is applied to the determinations of a food dye, phosphate ions and nitrite ions. The air-segmentation is effective for limiting amplitude damping through the axial dispersion, resulting in an improvement in sensitivity. This effect is more pronounced at shorter control periods and longer flow path lengths.

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Single image dehazing algorithm based on Dark Channel Prior (DCP) is widely known. More and more image dehazing algorithms based on DCP have been proposed. However, we found that it is more effective to use DCP in the RAW images before the ISP pipeline. In addition, for the problem of DCP failure in the sky area, we propose an algorithm to segment the sky region and compensate the transmission. Extensive experimental results on both subjective and objective evaluation demonstrate that the performance of the modified DCP (MDCP) has been greatly improved, and it is competitive with the state-of-the-art methods.

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We studied a new detection algorithm for the oscillation power range monitor (OPRM) system to suppress postulated neutronic/thermal-hydraulic instability events in boiling water reactors (BWRs) before exceeding the fuel cladding integrity limit. The new method evaluates the standard deviation for OPRM oscillatory periods instead of monitoring them directly. Instability is detected when the standard deviation remains lower than a setpoint for a certain elapsed time. This method aims at excluding the impact of the perturbation caused by OPRM noise components for each OPRM cell to the detection performance, utilizing statistics that represent the oscillatory characteristics for the instability criterion.
Toshiba's BWR system analysis code TRACT simulated the OPRM signals for an up-rated Advanced Boiling Water Reactor (ABWR) regional instability event to examine the applicability of the new algorithm to this new reactor. Since there are no plant instability data for ABWR, we estimated noise components based on the available stability test data and superimposed them on the simulated oscillation data. The new algorithm showed that the trip signal could be generated for the simulated regionally instable condition before the fuel cladding safety limit was reached.

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We study the weak-localization (WL) effect in mesoscopic wires of ferromagnetic metals, focusing on the decoherence caused by a magnetic domain wall (DW). The decoherence leads to suppression of the WL correction to conductance. A real-space approach is presented to describe the WL effect which explicitly takes into account the location of a DW. If the length L of a wire is much smaller than the phase coherence length L_φ, the WL correction is shown to depend on the location of the DW. In the opposite limit of L >> L_φ >> W (W: thickness of the DW), it is shown that the DW reduces the WL correction by a factor of (1-W/2L) compared with that in the absence of the DW. The influence of the DW on the amplitude of the Altshuler-Aronov-Spivak oscillation in a metallic ring partially replaced by a ferromagnetic wire is also discussed.

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