227 research outputs found
Macroscopic Many-Qubit Interactions in Superconducting Flux Qubits
Superconducting flux qubits are considered to investigate macroscopic
many-qubit interactions.
Many-qubit states based on current states can be manipulated through the
current-phase relation in each superconducting loop.
For flux qubit systems comprised of qubit loops, a general expression of
low energy Hamiltonian is presented in terms of low energy levels of qubits and
macroscopic quantum tunnelings between the many-qubit states.
Many-qubit interactions classified by {\em Ising type- or tunnel-}exchange
interactions can be observable experimentally.
Flux qubit systems can provide various artificial-spin systems to study
many-body systems that cannot be found naturally.Comment: 5 pages, 1 figur
Macroscopic Greenberger-Horne-Zeilinger and W states in flux qubits
We investigate two types of genuine three-qubit entanglement, known as the Greenberger-Horne-Zeilinger (GHZ) and W states, in a macroscopic quantum system. Superconducting flux qubits are theoretically considered in order to generate such states. A phase coupling is proposed to offer enough strength of interactions between qubits. While an excited state can be the W state, the GHZ state is formed at the ground state of the three flux qubits. The GHZ and W states are shown to be robust against external flux fluctuations for feasible experimental realizations
Utilizing University-based Enterprise to Foster Industry-Academia Collaboration in the Field of Product Development
University-based enterprise (UBE) system has been adopted and implemented in diverse fields focusing on practice-based learning. The aim of the presentation is to introduce the UBE system integrated into product development course and active collaborations with regional government and other companies to enhance students’ practical abilities. Presented are the UBE system and two cases utilizing the system for product development education
Role of Potassium-competitive Acid Blockers in the Treatment of Gastric Acid-related Disorders
Owing to their superior pharmacokinetic and pharmacodynamic profiles, potassium-competitive acid blockers (P-CABs) score over proton pump inhibitors (PPIs) in the treatment of gastric acid-related disorders and may provide clinical benefit in the management of these conditions. Previous studies have compared P-CABs with PPIs for treatment of gastric acid-related disorders, and current data show that P-CABs are non-inferior to PPIs in the treatment of erosive esophagitis and as maintenance therapy. P-CABs are useful for effective healing and as maintenance medications in patients with severe esophagitis. These drugs also aid with healing of peptic ulcers and artificial ulcers secondary to gastric endoscopic submucosal dissection (ESD). Few studies have discussed prevention of delayed ulcer bleeding after gastric ESD and ulcers associated with long-term nonsteroidal anti-inflammatory drug administration. Well-controlled, large-scale prospective studies are warranted in future to compare P-CABs with PPIs
Implementation of three-qubit Toffoli gate in a single step
Single-step implementations of multi-qubit gates are generally believed to
provide a simpler design, a faster operation, and a lower decoherence. For
coupled three qubits interacting with a photon field, a realizable scheme for a
single-step Toffoli gate is investigated. We find that the three qubit system
can be described by four effective modified Jaynes-Cummings models in the
states of two control qubits. Within the rotating wave approximation, the
modified Jaynes-Cummings models are shown to be reduced to the conventional
Jaynes-Cummings models with renormalized couplings between qubits and photon
fields. A single-step Toffoli gate is shown to be realizable with tuning the
four characteristic oscillation periods that satisfy a commensurate condition.
Possible values of system parameters are estimated for single-step Toffli gate.
From numerical calculation, further, our single-step Toffoli gate operation
errors are discussed due to imperfections in system parameters, which shows
that a Toffoli gate with high fidelity can be obtained by adjusting pairs of
the photon-qubit and the qubit-qubit coupling strengthes. In addition, a
decoherence effect on the Toffoli gate operation is discussed due to a thermal
reservoir.Comment: 8 pages, 4 figures, to appear in PR
PwRn1, a novel Ty3/gypsy-like retrotransposon of Paragonimus westermani: molecular characters and its differentially preserved mobile potential according to host chromosomal polyploidy
<p>Abstract</p> <p>Background</p> <p>Retrotransposons have been known to involve in the remodeling and evolution of host genome. These reverse transcribing elements, which show a complex evolutionary pathway with diverse intermediate forms, have been comprehensively analyzed from a wide range of host genomes, while the information remains limited to only a few species in the phylum Platyhelminthes.</p> <p>Results</p> <p>A LTR retrotransposon and its homologs with a strong phylogenetic affinity toward <it>CsRn1 </it>of <it>Clonorchis sinensis </it>were isolated from a trematode parasite <it>Paragonimus westermani </it>via a degenerate PCR method and from an insect species <it>Anopheles gambiae </it>by <it>in silico </it>analysis of the whole mosquito genome, respectively. These elements, designated <it>PwRn1 </it>and <it>AgCR-1 </it>– <it>AgCR-14 </it>conserved unique features including a t-RNA<sup>Trp </sup>primer binding site and the unusual CHCC signature of Gag proteins. Their flanking LTRs displayed >97% nucleotide identities and thus, these elements were likely to have expanded recently in the trematode and insect genomes. They evolved heterogeneous expression strategies: a single fused ORF, two separate ORFs with an identical reading frame and two ORFs overlapped by -1 frameshifting. Phylogenetic analyses suggested that the elements with the separate ORFs had evolved from an ancestral form(s) with the overlapped ORFs. The mobile potential of <it>PwRn1 </it>was likely to be maintained differentially in association with the karyotype of host genomes, as was examined by the presence/absence of intergenomic polymorphism and mRNA transcripts.</p> <p>Conclusion</p> <p>Our results on the structural diversity of <it>CsRn1</it>-like elements can provide a molecular tool to dissect a more detailed evolutionary episode of LTR retrotransposons. The <it>PwRn1</it>-associated genomic polymorphism, which is substantial in diploids, will also be informative in addressing genomic diversification following inter-/intra-specific hybridization in <it>P. westermani </it>populations.</p
An Empirical Study on L2 Accents of Cross-lingual Text-to-Speech Systems via Vowel Space
With the recent developments in cross-lingual Text-to-Speech (TTS) systems,
L2 (second-language, or foreign) accent problems arise. Moreover, running a
subjective evaluation for such cross-lingual TTS systems is troublesome. The
vowel space analysis, which is often utilized to explore various aspects of
language including L2 accents, is a great alternative analysis tool. In this
study, we apply the vowel space analysis method to explore L2 accents of
cross-lingual TTS systems. Through the vowel space analysis, we observe the
three followings: a) a parallel architecture (Glow-TTS) is less L2-accented
than an auto-regressive one (Tacotron); b) L2 accents are more dominant in
non-shared vowels in a language pair; and c) L2 accents of cross-lingual TTS
systems share some phenomena with those of human L2 learners. Our findings
imply that it is necessary for TTS systems to handle each language pair
differently, depending on their linguistic characteristics such as non-shared
vowels. They also hint that we can further incorporate linguistics knowledge in
developing cross-lingual TTS systems.Comment: Submitted to ICASSP 202
Latent Filling: Latent Space Data Augmentation for Zero-shot Speech Synthesis
Previous works in zero-shot text-to-speech (ZS-TTS) have attempted to enhance
its systems by enlarging the training data through crowd-sourcing or augmenting
existing speech data. However, the use of low-quality data has led to a decline
in the overall system performance. To avoid such degradation, instead of
directly augmenting the input data, we propose a latent filling (LF) method
that adopts simple but effective latent space data augmentation in the speaker
embedding space of the ZS-TTS system. By incorporating a consistency loss, LF
can be seamlessly integrated into existing ZS-TTS systems without the need for
additional training stages. Experimental results show that LF significantly
improves speaker similarity while preserving speech quality.Comment: Accepted to ICASSP 202
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