40 research outputs found

    Data assessment and prioritization in mobile networks for real-time prediction of spatial information using machine learning

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    A new framework of data assessment and prioritization for real-time prediction of spatial information is presented. The real-time prediction of spatial information is promising for next-generation mobile networks. Recent developments in machine learning technology have enabled prediction of spatial information, which will be quite useful for smart mobility services including navigation, driving assistance, and self-driving. Other key enablers for forming spatial information are image sensors in mobile devices like smartphones and tablets and in vehicles such as cars and drones and real-time cognitive computing like automatic number/license plate recognition systems and object recognition systems. However, since image data collected by mobile devices and vehicles need to be delivered to the server in real time to extract input data for real-time prediction, the uplink transmission speed of mobile networks is a major impediment. This paper proposes a framework of data assessment and prioritization that reduces the uplink traffic volume while maintaining the prediction accuracy of spatial information. In our framework, machine learning is used to estimate the importance of each data element and to predict spatial information under the limitation of available data. A numerical evaluation using an actual vehicle mobility dataset demonstrated the validity of the proposed framework. Two extension schemes in our framework, which use the ensemble of importance scores obtained from multiple feature selection methods, are also presented to improve its robustness against various machine learning and feature selection methods. We discuss the performance of those schemes through numerical evaluation

    Possible interpretations of the joint observations of UHECR arrival directions using data recorded at the Telescope Array and the Pierre Auger Observatory

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    Rare recurrence of a multilocular cystic leiomyoma following myomectomy

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    Multilocular cystic leiomyomas rarely develop following myomectomy. To the best of our knowledge, there are no published reports on recurrent multilocular cystic leiomyoma following myomectomy. We here present such a case. A 45-year-old woman visited our outpatient clinic because of heavy vaginal bleeding. She underwent laparoscopic myomectomy for a solid mass in the uterine cavity. Subsequent pathological examination of the operative specimen revealed a tumour with well-demarcated borders and spindle cells arranged in intersecting fascicles. Seven days postoperatively, ultrasonography revealed a cystic lesion. Magnetic resonance imaging performed 28 months postoperatively revealed a large, well-defined, multilocular cystic mass that was homogeneously hyperintense on T2-weighted images on the exterior of the uterus. Abdominal hysterectomy was performed. On pathological examination of the operative specimen, she was found to have a leiomyoma with marked cystic degeneration. Incomplete excision of a multilocular cystic leiomyoma may result in recurrence in the form of a large cystic mass. Clinical differentiation between a multilocular cystic leiomyoma and an ovarian tumour may be difficult. Complete resection of a uterine multilocular cystic lesion prevents recurrence

    Double-Bundle Anterior Cruciate Ligament Reconstruction Using Hamstring Tendon Hybrid Grafts in Patients Over 40 Years of Age : Comparisons Between Different Age Groups

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    Background: Several recent studies have reported that favorable clinical results and a high level of patient satisfaction can generally be obtained with no increased risk of complications after single-bundle anterior cruciate ligament (ACL) reconstruction performed in patients >40 years of age. However, no studies have yet clarified the age-based differences in clinical outcomes after double-bundle reconstruction. Purpose: To compare clinical outcomes after double-bundle ACL reconstruction using hamstring tendon hybrid grafts between patients in 2 different age groups: ≥40 years and <40 years. Study Design: Cohort study; Level of evidence, 3. Methods: A retrospective study was conducted using 96 patients (48 men, 48 women ; mean age, 37 years) who underwent unilateral ACL reconstruction between 2008 and 2011. These patients were divided into 2 groups: group M included patients ≥40 years of age (n = 40 patients), and group Y included patients <40 years of age (n = 56 patients). All patients underwent the same anatomic double-bundle ACL reconstruction procedure. Clinical outcomes were evaluated at 2 years after surgery. Tunnel enlargement was also evaluated by computed digital radiography at 1 week and 2 years after surgery. Results: Mean postoperative side-to-side differences in anterior laxity were 0.5 ± 1.9 mm and 1.2 ± 1.5 mm in groups M and Y, respectively; there was a significant difference between the 2 groups (P = .039). There were no significant differences between the groups in Lysholm knee scores, International Knee Documentation Committee (IKDC) scores, or peak muscle torque of the hamstring. On the other hand, peak muscle torque of the quadriceps was significantly lower in group M (81%) than in group Y (89%) (P = .025). With respect to femoral tunnel enlargement, the posterolateral tunnel in group M was significantly larger than that in group Y on anteroposterior and lateral radiographs (P = .015 and P = .002, respectively). Conclusion: Equivalent clinical outcomes were seen between the 2 age groups after double-bundle ACL reconstruction. Postoperative anterior laxity was significantly less in older patients than in younger patients, however, older patients had significantly less quadriceps muscle strength than younger patients. Surgeons should be aware of residual muscle weakness and tunnel enlargement when performing double-bundle ACL reconstruction in older patients
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