Search results for "i-US"
showing 10 items of 12 documents
Role of i-CT, i-US, and Neuromonitoring in Surgical Management of Brain Cavernous Malformations and Arteriovenous Malformations: A Case Series.
2022
OBJECTIVE: We retrospectively reviewed the institutional experience in patients who underwent microsurgical resection of cavernous malformations (CMs) or arteriovenous malformations (AVMs) using a multimodal intraoperative protocol including neuronavigation, intraoperative ultrasound (i-US), computed tomography (i-CT), and neuromonitoring.METHODS: Twenty-four patients (14 male), with a mean age of 47.5 years (range 27 - 73), have been included: 20 of them suffered from CMs and 4 suffered from AVMs.Neuromonitoring was used in 18 cases, when lesions were located in eloquent areas; 2 patients underwent awake craniotomy. First, an i-CT scan with and without contrast was acquired after patient p…
The case of literacy motivation : Playful 3D immersive learning environments and problem-focused education for blended digital storytelling
2018
The University of Patras' Library Services designed and offered to primary and secondary schools the pilot educational program “From the Ancient to the Modern Tablets”, featuring immersive multimedia learning experiences about the book history. The pilot program consisted of three stages: a playful library tour, followed by an interactive game-based digital storytelling activity with game elements, and a collaborative creative reflective hands-on activity. Utilizing the avatar psychology power, the visualization and simulation affordances of 3D immersive learning environments and the appeal of storytelling and game-based learning, the “gamified” blended narrative on the book evolution enabl…
Multi-user interference mitigation under limited feedback requirements for WCDMA systems with base station cooperation
2016
One of the techniques that has been recently identified for dealing with multi-user interference (MUI) in future communications systems is base station (BS) cooperation or joint processing. However, perfect MUI cancellation with this technique demands severe synchronization requirements, perfect and global channel state information (CSI), and an increased backhaul and signaling overhead. In this paper, we consider a more realistic layout with the aim of mitigating the MUI, where only local CSI is available at the BSs. Due to synchronization inaccuracies and errors in the channel estimation, the system becomes partially asynchronous. In the downlink of wideband code division multiple access …
Engaging learners through virtual worlds
2010
Abstract The aim of this paper is to explore how virtual worlds could support the engagement for learning. This paper reviews the results of studies that utilized virtual worlds to engage learners. The results are examined in two levels, namely learning gains and design principles. It has been found out that deeper learner engagement results in higher learning gains. In some studies better content retention is also noted. Many studies also suggest design principles for using virtual worlds for facilitating engaged learning. This paper builds a framework for the design and use of virtual worlds in education for better learner engagement.
Experiences and motivations of the young for participation in virtual worlds
2010
Abstract The aim of this paper is to analyze the motivations and experiences of children to utilize virtual worlds. The paper identifies the activities that children perform in virtual worlds, features they use as well as the reasons for abandoning these virtual worlds. The paper presents results of a qualitative field study. The results indicate that features that are liked in the virtual worlds are similar to games. The main reasons to abandon virtual worlds were increased needs for social networking and better gaming experiences. Students showed interest in using games and virtual worlds at schools, but were generally rather skeptic about this possibility.
Identification of the inertial model for innovative semi-immergible USV (SI-USV) drone for marine and lakes operations
2015
The proposed project shows the results obtained in the implementation and testing in lacustrine and marine environment of a nautical remote controlled vehicle with surface navigation and innovative features Semi-Immergible (SI-USV). This vehicle is based on a pending patent belonging to Palermo University (Patent Pending RM2012A000209 and Patent RM2014Z000060) concerning innovative semi-immersible vehicles (SI-Drone), that can be remotely controlled from the ground, air, satellite and sea also during the semi-immersible operation. Given its low draft, the electric powered vehicle, coupled with jet propulsion, makes it possible to navigate in shallow waters, coastal shipping or sandbars.
A innovative semi-immergible USV (SI-USV) drone for marine and lakes operations with instrumental telemetry and acoustic data acquisition capability
2015
The proposed project shows the results obtained in the implementation and testing in lacustrine and marine environment of a nautical remote controlled vehicle with surface navigation and innovative features Semi-Immersible (SI-USV). This vehicle is based on a pending patent belonging to Palermo University (Patent Pending RM2012A000209 and RM2012A000209) concerning innovative semi-immersible vehicles (SI-Drone), that can be remotely controlled from the ground, air, satellite and sea also during the semi-immersible operation. The vehicle with electric power is coupled with a jet propulsion, given the low draft, makes it possible to navigate in shallow waters or coastal shipping or sandbars. T…
A performance study of LTE MIMO-OFDM systems using the extended one-ring MIMO channel model
2012
In this paper, we consider a long-term evolution (LTE) system for the downlink by using multiple-input multiple-output (MIMO) orthogonal frequency division multiplexing (OFDM) techniques. The downlink channel is modeled by the socalled extended MIMO one-ring model. This model extends the well-known narrowband one-ring model with respect to frequency selectivity. The symbol error rate (SER) performance of the LTE MIMO-OFDM system is investigated for the downlink by employing different kinds of spatial encoders, where it is assumed that the channel state information (CSI) is perfectly known. For comparison, the space-time block coding (STBC) scheme, the vertical Bell Laboratories layered spac…
Energy efficient and distributed resource allocation for wireless powered OFDMA multi-cell networks
2017
In this paper, we investigate the energy efficient resource allocation problem for the wireless powered OFDMA multi-cell networks. In the considered system, the users who have data to transmit in the uplink can only be empowered by the wireless power obtained from multiple base stations (BSs) with a large scale of multiple antennas in the downlink. A time division protocol is considered to divide the time of wireless power transfer (WPT) in the downlink and wireless information transfer (WIT) in the uplink into separate time slot. With the objective to improve the energy efficiency (EE) of the system, we propose the antenna selection, time allocation, subcarrier and power allocation schemes…