Search results for "LESS"
showing 10 items of 2452 documents
Inverse kinematic control of an industrial robot used in Vessel-to-Vessel Motion Compensation
2017
An increased level of complex offshore load handling operations is expected due to an increased amount of floating wind turbines, remote fish farms, and autonomous shipping, and in general more advanced operations to be carried out at sea. A common problem for these applications is that both equipment and personnel have to be transported between two floating vessels at sea. An investigation of the Vessel-to-Vessel Motion Compensation (VVMC) problem may increase the efficiency and safety of such operations in the future. In this paper, a control algorithm has been developed and experimentally tested in the Norwegian Motion Laboratory featuring two Stewart platforms (SPs), an industrial robot…
Survey of Cyber Threats in Air Traffic Control and Aircraft Communications Systems
2018
Air traffic control systems based on the ADS-B standard have been widely adopted in civil aviation to the point that they are now considered the de facto standard. ADS-B provides major benefits to airports and airlines by increasing the safety of air traffic management and control and allowing more flights to travel near busy airports. However, the ADS-B technology lacks sufficient security measures. The ADS-B system is vulnerable and exposed to cyberattacks. We survey the potential known threats and attacks against ADS-B and assess the potential cybersecurity threats to air traffic management and control. The widespread use of ADS-B and the lack of security features in it, i.e., all the AD…
Secure and efficient verification for data aggregation in wireless sensor networks
2017
Summary The Internet of Things (IoT) concept is, and will be, one of the most interesting topics in the field of Information and Communications Technology. Covering a wide range of applications, wireless sensor networks (WSNs) can play an important role in IoT by seamless integration among thousands of sensors. The benefits of using WSN in IoT include the integrity, scalability, robustness, and easiness in deployment. In WSNs, data aggregation is a famous technique, which, on one hand, plays an essential role in energy preservation and, on the other hand, makes the network prone to different kinds of attacks. The detection of false data injection and impersonation attacks is one of the majo…
Subjective Logic-Based In-Network Data Processing for Trust Management in Collocated and Distributed Wireless Sensor Networks
2018
While analyzing an explosive amount of data collected in today’s wireless sensor networks (WSNs), the redundant information in the sensed data needs to be handled. In-network data processing is a technique which can eliminate or reduce such redundancy, leading to minimized resource consumption. On the other hand, trust management techniques establish trust relationships among nodes and detect unreliable nodes. In this paper, we propose two novel in-network data processing schemes for trust management in static WSNs. The first scheme targets at networks, where sensor nodes are closely collocated to report the same event. Considering both spatial and temporal correlations, this scheme generat…
Two novel subjective logic-based in-network data processing schemes in wireless sensor networks
2016
Wireless sensor networks (WSNs) consist of connected low-cost and small-size sensor nodes. The sensor nodes are characterized by various limitations, such as energy availability, processing power, and storage capacity. Typically, nodes collect data from an environment and transmit the raw or processed data to a sink. However, the collected data contains often redundant information. An in-network processing scheme attempts to eliminate or reduce such redundancy in sensed data. In this paper, we propose two in-network data processing schemes for WSNs, which are built based on a lightweight algebra for data processing. The schemes bring also benefits like decreased network traffic load and inc…
Testing of wireless sensor performance in Vessel-to-Vessel Motion Compensation
2016
Relative Vessel-to-Vessel Motion Compensation (VVMC) between two floating vessels can be considered an extension of existing Active Heave Compensation (AHC), which is current state-of-the-art in the offshore industry. In this paper, the experimental results from a small-scale experimental setup of a VVMC scenario are presented. The work focuses on the kinematics related to VVMC, sensor accuracy of Motion Reference Units (MRUs), and the communication delay related to wireless transmission of MRU data between two floating vessels. The accuracies of the MRU sensors are good and verified to be less than 5% of the heave amplitude. The wireless communication link had a typical time-delay of 8ms. …
Age-related trends of lesser pelvic architecture in females and males: a computed tomography pelvimetry study
2017
The pelvis and the spine form a system balancing human skeleton. Within this system, the pelvis adapts to age-related changes in the spine. Previous studies were predominantly focused on changes of pelvic parameters in the sagittal plane. The aim of this study was to reveal age-related changes of lesser pelvic dimensions at different levels of the pelvic cavity in the sagittal and coronal planes and to explore sexual dimorphism in age-related tendencies. The computed tomography pelvimetry was performed on the three-dimensional workstation. The research sample included 211 females aged 18 to 84 years and 181 males aged 18 to 82 years, who underwent an examination at the Riga East University …
Effect of green tea extract on enteric viruses and its application as natural sanitizer
2017
In this work, the effect of green tea extract (GTE) was assessed against murine norovirus (MNV) and hepatitis A virus (HAV) at different temperatures, exposure times and pH conditions. Initially, GTE at 0.5 and 5 mg/ml were individually mixed with each virus at 5 log TCID50/ml and incubated 2 h at 37 °C at different pHs (from 5.5 to 8.5). GTE affected both viruses depending on pH with higher reductions observed in alkaline conditions. Secondly, different concentrations of GTE (0.5 and 5 mg/ml) were mixed with viral suspensions and incubated for 2 or 16 h at 4, 25 and 37 °C at pH 7.2. A concentration-, temperature- and exposure time-dependent response was showed by GTE in suspension tests, w…
A TRAPPC6B splicing variant associates to restless legs syndrome
2016
Abstract INTRODUCTION: RLS is a common movement disorders with a strong genetic component in its pathophysiology, but, up to now, no causative mutation has been reported. METHODS: We re-evaluated the previously described RLS2 family by exome sequencing. RESULTS: We identified fifteen variations in the 14q critical region. The c.485G > A transition of the TRAPPC6B gene segregates with the RLS2 haplotype, is absent in 200 local controls and is extremely rare in 12988 exomes from the Exome Variant Server (EVS). This variant alters a splicing site and hampers the normal transcript processing by promoting exon 3-skipping as demonstrated by minigene transfection and by patient transcripts. CON…
Circadian clock of Drosophila montana is adapted to high variation in summer day lengths and temperatures prevailing at high latitudes
2016
Photoperiodic regulation of the circadian rhythms in insect locomotor activity has been studied in several species, but seasonal entrainment of these rhythms is still poorly understood. We have traced the entrainment of activity rhythm of northern Drosophila montana flies in a climate chamber mimicking the photoperiods and day and night temperatures that the flies encounter in northern Finland during the summer. The experiment was started by transferring freshly emerged females into the chamber in early and late summer conditions to obtain both non-diapausing and diapausing females for the studies. The locomotor activity of the females and daily changes in the expression levels of two core …