189 research outputs found
Observation of resonant dipolar collisions in ultracold NaRb rotational mixtures
We report the investigation on dipolar collisions in rotational state
mixtures of ultracold bosonic NaRb molecules. The large resonant
dipole-dipole interaction between molecules in rotational states of opposite
parities brings about significant modifications to their collisions, even when
an electric field is not present. In this work, this effect is revealed by
measuring the dramatically enhanced two-body loss rate constants in the
mixtures. In addition, the dipolar interaction strength can be tuned by
preparing the NaRb mixture in different rotational levels with microwave
spectroscopy. When the rotational level combination is not of the lowest
energy, contributions from hyperfine changing collisions are also observed. Our
measured loss rate constants are in good agreement with a quantum
close-coupling calculation which we also present in full detail.Comment: Expanded version with the theory included in detai
Subnatural-Linewidth Polarization-Entangled Photon Pairs with Controllable Temporal Length
We demonstrate an efficient experimental scheme for producing
polarization-entangled photon pairs from spontaneous four-wave mixing (SFWM) in
a laser-cooled Rb atomic ensemble, with a bandwidth (as low as 0.8 MHz)
much narrower than the rubidium atomic natural linewidth. By stabilizing the
relative phase between the two SFWM paths in a Mach-Zehnder interferometer
configuration, we are able to produce all four Bell states. These
subnatural-linewidth photon pairs with polarization entanglement are ideal
quantum information carriers for connecting remote atomic quantum nodes via
efficient light-matter interaction in a photon-atom quantum network.Comment: Title changed, published version, 5 pages + 3 pages Supplemental
Materia
Evaluating Learning-to-Rank Models for Prioritizing Code Review Requests using Process Simulation
In large-scale, active software projects, one of the main challenges with code review is prioritizing the many Code Review Requests (CRRs) these projects receive. Prior studies have developed many Learning-to-Rank (LtR) models in support of prioritizing CRRs and adopted rich evaluation metrics to compare their performances. However, the evaluation was performed before observing the complex interactions between CRRs and reviewers, activities and activities in real-world code reviews. Such a pre-review evaluation provides few indications about how effective LtR models contribute to code reviews. This study aims to perform a post-review evaluation on LtR models for prioritizing CRRs. To establish the evaluation environment, we employ Discrete-Event Simulation (DES) paradigm-based Software Process Simulation Modeling (SPSM) to simulate real-world code review processes, together with three customized evaluation metrics. We develop seven LtR models and use the historical review orders of CRRs as baselines for evaluation. The results indicate that employing LtR can effectively help to accelerate the completion of reviewing CRRs and the delivery of qualified code changes. Among the seven LtR models, LambdaMART and AdaRank are particularly beneficial for accelerating completion and delivery, respectively. This study empirically demonstrates the effectiveness of using DES-based SPSM for simulating code review processes, the benefits of using LtR for prioritizing CRRs, and the specific advantages of several LtR models. This study provides new ideas for software organizations that seek to evaluate LtR models and other artificial intelligence-powered software techniques
One-for-All: Towards Universal Domain Translation with a Single StyleGAN
In this paper, we propose a novel translation model, UniTranslator, for
transforming representations between visually distinct domains under conditions
of limited training data and significant visual differences. The main idea
behind our approach is leveraging the domain-neutral capabilities of CLIP as a
bridging mechanism, while utilizing a separate module to extract abstract,
domain-agnostic semantics from the embeddings of both the source and target
realms. Fusing these abstract semantics with target-specific semantics results
in a transformed embedding within the CLIP space. To bridge the gap between the
disparate worlds of CLIP and StyleGAN, we introduce a new non-linear mapper,
the CLIP2P mapper. Utilizing CLIP embeddings, this module is tailored to
approximate the latent distribution in the P space, effectively acting as a
connector between these two spaces. The proposed UniTranslator is versatile and
capable of performing various tasks, including style mixing, stylization, and
translations, even in visually challenging scenarios across different visual
domains. Notably, UniTranslator generates high-quality translations that
showcase domain relevance, diversity, and improved image quality. UniTranslator
surpasses the performance of existing general-purpose models and performs well
against specialized models in representative tasks. The source code and trained
models will be released to the public
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