616 research outputs found

    Coherent Control of Causal Order of Entanglement Distillation

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    We present an application of indefinite causal order in quantum communication: a compound entanglement distillation protocol which features two steps of a basic distillation protocol applied in a coherent superposition of two causal orders. This is achieved by using one faulty entangled pair to control-swap two others before a fourth pair is combined with the two swapped ones consecutively. As a result, the protocol distills the four faulty entangled states into one of a higher fidelity. Our protocol has a higher fidelity of distillation and probability of success for some input faulty pairs than conventional concatenations of the basic protocol that follow a definite distillation order. Our proposal shows advantage of indefinite causal order in an application setting consistent with the requirements of quantum communication

    Numerical simulation of Quasi-Normal Modes in time-dependent background

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    We study the massless scalar wave propagation in the time-dependent Schwarzschild black hole background. We find that the Kruskal coordinate is an appropriate framework to investigate the time-dependent spacetime. A time-dependent scattering potential is derived by considering dynamical black hole with parameters changing with time. It is shown that in the quasinormal ringing both the decay time-scale and oscillation are modified in the time-dependent background.Comment: 10 pages, 8 figures; reference adde

    Quadratic Volume Preserving Maps

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    We study quadratic, volume preserving diffeomorphisms whose inverse is also quadratic. Such maps generalize the Henon area preserving map and the family of symplectic quadratic maps studied by Moser. In particular, we investigate a family of quadratic volume preserving maps in three space for which we find a normal form and study invariant sets. We also give an alternative proof of a theorem by Moser classifying quadratic symplectic maps.Comment: Ams LaTeX file with 4 figures (figure 2 is gif, the others are ps

    PELATIHAN TENTANG TUMBUH KEMBANG BAYI USIA 6-4 BULAN

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    Asupan gizi melalui ASI dapat menunjang proses tumbuh kembang anak yang lebih optimal. Namun untuk saat ini masih kurangnya perhatian ibu dalam pemberian ASI eksklusif. Instrumen Kuesioner Pra Skrining Perkembangan (KPSP) dapat digunakan untuk deteksi dini perkembangan anak, sehingga bisa diketahui seberapa jauh pengaruh ASI pada proses perkembangan anak. Tujuan pengapdian masyarakat ini untuk mengetahui pengetahuan ibu tentang tumbuh kembang bayi usia 6-4 bulan membantu bayi dalam memenuhi kebutuhan gizi, memperkenalkan mereka pada brebagai jenis makanan padat, dan membantu dalam perkembangan keterampilan makan. Metode yang digunakan dalam kegiatan pengabdian masyarakat tahap antara lain dengan pelatihan. Memberikan tambahan nutrisi yang diperlukan bayi karena ASI atau formula saia tidak cukup untuk memenuhi kebutuhan nutrisi mereka. Hasil yang dicapai setelah mengikuti pelatihan dan diskusi masyarakat Kelurahan Helvetia mengetahui peningkatan terhadap kualitas ibu dalam pemberian Mpasi pada bayi

    Optimized Dynamical Decoupling Sequences in Protecting Two-Qubit States

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    Aperiodic dynamical decoupling (DD) sequences of π\pi pulses are of great interest to decoherence control and have been recently extended from single-qubit to two-qubit systems. If the environmental noise power spectrum is made available, then one may further optimize aperiodic DD sequences to reach higher efficiency of decoherence suppression than known universal schemes. This possibility is investigated in this work for the protection of two-qubit states, using an exactly solvable pure dephasing model including both local and nonlocal noise. The performance of optimized DD sequences in protecting two-qubit states is compared with that achieved by nested Uhrig's DD (nested-UDD) sequences, for several different types of noise spectrum. Except for cases with noise spectrum decaying slowly in the high-frequency regime, optimized DD sequences with tens of control pulses can perform orders of magnitude better than that of nested-UDD. A two-qubit system with highly unbalanced local noise is also examined to shed more light on a recent experiment. Possible experiments that may be motivated by this work are discussed.Comment: 9 pages, two figure

    Quasinormal Modes in three-dimensional time-dependent Anti-de Sitter spacetime

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    The massless scalar wave propagation in the time-dependent BTZ black hole background has been studied. It is shown that in the quasi-normal ringing both the decay and oscillation time-scales are modified in the time-dependent background.Comment: 8 pages and 7 figure

    Die Qualität von Schweizer Medien auf Instagram und TikTok: Jahrbuch Qualität der Medien Studie 2 / 2023

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    The non-zero divisor graph of ring of integers modulo six and the hamiltonian quaternion over integers modulo two

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    The study of graph theory was introduced and widely researched since many practical problems can be represented by graphs. A non-zero divisor graph is a graph in which its set of vertices is the non-zero elements of the ring and the vertices x and y are adjacent if and only if xy ≠ 0. In this study, we introduced the non-zero divisor graphs of some finite commutative rings in specific the ring of in tegers modulo 6, 6 and ring of Hamiltonian quaternion, (2). First, the non-zero divisors of the commutative rings are found. Then, the non-zero divisor graphs are constructed. Finally, some properties of the graph, including the chromatic number, clique number, girth and the diameter are obtained

    Developing Automated Computer Algorithms to Track Periodontal Disease Change from Longitudinal Electronic Dental Records

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    Objective: To develop two automated computer algorithms to extract information from clinical notes, and to generate three cohorts of patients (disease improvement, disease progression, and no disease change) to track periodontal disease (PD) change over time using longitudinal electronic dental records (EDR). Methods: We conducted a retrospective study of 28,908 patients who received a comprehensive oral evaluation between 1 January 2009, and 31 December 2014, at Indiana University School of Dentistry (IUSD) clinics. We utilized various Python libraries, such as Pandas, TensorFlow, and PyTorch, and a natural language tool kit to develop and test computer algorithms. We tested the performance through a manual review process by generating a confusion matrix. We calculated precision, recall, sensitivity, specificity, and accuracy to evaluate the performances of the algorithms. Finally, we evaluated the density of longitudinal EDR data for the following follow-up times: (1) None; (2) Up to 5 years; (3) > 5 and ≤ 10 years; and (4) >10 and ≤ 15 years. Results: Thirty-four percent (n = 9954) of the study cohort had up to five years of follow-up visits, with an average of 2.78 visits with periodontal charting information. For clinician-documented diagnoses from clinical notes, 42% of patients (n = 5562) had at least two PD diagnoses to determine their disease change. In this cohort, with clinician-documented diagnoses, 72% percent of patients (n = 3919) did not have a disease status change between their first and last visits, 669 (13%) patients’ disease status progressed, and 589 (11%) patients’ disease improved. Conclusions: This study demonstrated the feasibility of utilizing longitudinal EDR data to track disease changes over 15 years during the observation study period. We provided detailed steps and computer algorithms to clean and preprocess the EDR data and generated three cohorts of patients. This information can now be utilized for studying clinical courses using artificial intelligence and machine learning methods.Dr. Thyvalikakath's start-up funds through the IU School of Dentistr
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