388 research outputs found

    Experimental scheme for qubit and qutrit symmetric informationally complete positive operator-valued measurements using multiport devices

    Full text link
    It is crucial for various quantum information processing tasks that the state of a quantum system can be determined reliably and efficiently from general quantum measurements. One important class of measurements for this purpose is symmetric informationally complete positive operator-valued measurements (SIC-POVMs). SIC-POVMs have the advantage of providing an unbiased estimator for the quantum state with the minimal number of outcomes needed for full tomography. By virtue of Naimark's dilation theorem, any POVM can always be realized with a suitable coupling between the system and an auxiliary system and by performing a projective measurement on the joint system. In practice, finding the appropriate coupling is rather non-trivial. Here we propose an experimental design for directly implementing SIC-POVMs using multiport devices and path-encoded qubits and qutrits, the utility of which has recently been demonstrated by several experimental groups around the world. Furthermore, we describe how these multiports can be attained in practice with an integrated photonic system composed of nested linear optical elements.Comment: 7 pages, 5 figures; v2 published versio

    A diagnosis of well-being: a phenomenological study exploring women resident physicians’ perceptions of their personal experiences with occupational burnout and attending physicians’ leadership styles

    Get PDF
    This qualitative, hermeneutic phenomenological research study explored the shared lived experience of occupational burnout and wellness in female Resident Physicians. The phenomenon was explored to identify if the Residents believed their Attending Physicians’ leadership styles ameliorated or exacerbated their feelings of occupational burnout. The theoretical frameworks of Herzberg’s Two-Factor Theory (Gardner, 1977) and Positive Psychology (Seligman, 2019) were used to examine the Residents’ ability to navigate their workplaces. Virtual, semi-structured interviews were conducted to gain a perspective of the female physicians’ residency experience and to learn how each felt their Attendings’ leadership styles impacted them. The hermeneutic phenomenological approach identified common themes from the interviews and highlighted the following: (a) their training experience as female Residents, (b) their experience of occupational burnout, (c) their perceptions of leadership styles that alleviated or exacerbated occupational burnout; and (d) the coping strategies and social support they employed when navigating occupational situations that promoted occupational well-being or exacerbated occupational burnout. This research study offered a perspective on how occupational burnout impacts female Residents and how medical leaders, such as Attending Physicians, might help to assuage or prevent this phenomenon from befalling them so early in their medical careers

    Multiple vocabulary coding for 3D shape retrieval using Bag of Covariances

    Get PDF
    Bag of Covariance matrices (BoC) have been recently introduced as an extension of the standard Bag of Words (BoW) to the space of positive semi-definite matrices, which has a Riemannian structure. BoC descriptors can be constructed with various Riemannian metrics and using various quantization approaches. Each construction results in some quantization errors, which are often reduced by increasing the vocabulary size. This, however, results in a signature that is not compact, increasing both the storage and computation complexity. This article demonstrates that a compact signature, with minimum distortion, can be constructed by using multiple vocabulary based coding. Each vocabulary is constructed from a different quantization method of the covariance feature space. The proposed method also extracts non-linear dependencies between the different BoC signatures to compose the final compact signature. Our experiments show that the proposed approach can boost the performance of the BoC descriptors in various 3D shape classification and retrieval tasks

    Interference model and evaluation in LTE networks

    No full text
    International audienceThe purpose of this paper is to evaluate the impact of frequency parameter settings while evaluating interference model in LTE (Long Term Evolution); the work is applied on a network. We develop and validate the interference model based on SINR which is used by 3GPP (3rd Group Partnership Project) to estimate the quality of signal received by UE (User Equipment) and issued from eNB (enhanced Node Base). For this aim, two frequency schemes have been compared: the frequency reuse 1 scheme whereby the whole available bandwidth is used in each cell/sector and the frequency reuse 3 scheme in which the entire bandwidth is divided into 3 non-overlapping groups and assigned to 3 co-site sectors within each cell

    Possibilistic networks parameter learning: Preliminary empirical comparison

    Get PDF
    International audienceLike Bayesian networks, possibilistic ones compactly encode joint uncertainty representations over a set of variables. Learning possibilistic networks from data in general and from imperfect or scarce data in particular, has not received enough attention. Indeed, only few works deal with learning the structure and the parameters of a possibilistic network from a dataset. This paper provides a preliminary comparative empirical evaluation of two approaches for learning the parameters of a possibilistic network from empirical data. The first method is a possibilistic approach while the second one first learns imprecise probability measures then transforms them into possibility distributions by means of probability-possibility transformations. The comparative evaluation focuses on learning belief networks on datasets with missing data and scarce datasets

    Reducing Disparities by way of a Cancer Disparities Research Training Program

    Full text link
    Background: For minority populations, there is a continuing disparity in the burden of death and illness from cancer. Research to address this disparity should be conducted by investigators who can best understand and address the needs of culturally diverse communities. However, minorities are under-represented in health-related research. The goal of this project was to develop and evaluate an approach to motivating and preparing master’s degree students for careers dedicated to cancer disparities research. Method: A Cancer Disparities Research Training Program (CDRTP) was initiated in 2010. The program consists of coursework, practicum experiences, and research opportunities. Assessment of the curriculum is based on monitoring achievement of evaluation indicators and includes a quantitative assessment and qualitative approach. Results: In its first three years, the program graduated 20 trainees, all of whom were minorities (18 African Americans and two Asians). When asked about career goals, two-thirds of the trainees indicated interest in pursuing careers in research on cancer prevention and control. The trainees expressed high satisfaction with the courses, instructor, materials, and curriculum. Although trainees had suggestions about course details, evaluations overall were positive. Across focus groups, three recurrent themes emerged regarding activities to enhance the student experience: having a wider variety of topics, more guest speakers, and field trips. Conclusion: The CDRTP was intended to recruit students – primarily African Americans – into research on prevention and control of cancer disparities. Although final evaluation of the program’s overall outcome will not be available for several years, a preliminary evaluation indicates the program is being successful

    Interference model and antenna parameters setting effects on 4G-LTE networks coverage

    No full text
    International audienceThe currently emerging Long Term Evolution 4G-LTE cellular networks are based on new technique of transmission called the Orthogonal Frequency Division Multiple Access (OFDMA). This paper shows the interest of robust approach due to the uncertainty of traffic distribution. First, we develop and validate the interference model based on SINR metric for the deployment of the LTE network, and then we use greedy algorithms to show how frequency and tilt parameter settings can impact the coverage performance metric. Two frequency schemes have been compared to validate our model: the frequency reuse 1 scheme whereby the whole available bandwidth is used in each cell/sector and the frequency reuse 3 scheme in which the entire bandwidth is divided into 3 non-overlapping groups and assigned to 3 co-site sectors within each cell
    • …
    corecore