scholarly journals Prototype Design and Experimental Evaluation of Autonomous Collaborative Communication System for Emerging Maritime Use Cases

Sensors ◽  
2021 ◽  
Vol 21 (11) ◽  
pp. 3871
Author(s):  
Jiri Pokorny ◽  
Khanh Ma ◽  
Salwa Saafi ◽  
Jakub Frolka ◽  
Jose Villa ◽  
...  
Keyword(s):  
Communication System ◽  
Autonomous Vehicles ◽  
High Speed ◽  
High Capacity ◽  
Workplace Safety ◽  
Unmanned Vehicles ◽  
Use Cases ◽  
Automated Systems ◽  
Collaborative Communication ◽  
Wide Range

Automated systems have been seamlessly integrated into several industries as part of their industrial automation processes. Employing automated systems, such as autonomous vehicles, allows industries to increase productivity, benefit from a wide range of technologies and capabilities, and improve workplace safety. So far, most of the existing systems consider utilizing one type of autonomous vehicle. In this work, we propose a collaboration of different types of unmanned vehicles in maritime offshore scenarios. Providing high capacity, extended coverage, and better quality of services, autonomous collaborative systems can enable emerging maritime use cases, such as remote monitoring and navigation assistance. Motivated by these potential benefits, we propose the deployment of an Unmanned Surface Vehicle (USV) and an Unmanned Aerial Vehicle (UAV) in an autonomous collaborative communication system. Specifically, we design high-speed, directional communication links between a terrestrial control station and the two unmanned vehicles. Using measurement and simulation results, we evaluate the performance of the designed links in different communication scenarios and we show the benefits of employing multiple autonomous vehicles in the proposed communication system.

Broadband Solutions for the Last Mile to Malaysian Residential Customers

2009 ◽  
pp. 164-170 ◽  
Author(s):  
Saravanan Nathan Lurudusamy
Keyword(s):  
Data Transmission ◽  
High Speed ◽  
Data Transfer ◽  
Full Range ◽  
National Policy ◽  
High Capacity ◽  
Broadband Service ◽  
Large Bandwidth ◽  
Wide Range ◽  
Policy Objectives

Broadband is a term that describes the Internet as a function of high-speed data connections and large bandwidth. The Federation Communication Commission (FCC) defines broadband service as data transmission speeds exceeding 200 kilobits per second (Kbps), or 200,000 bits per second, in at least one direction, either downstream or upstream. Its fundamental ability to bring about change in the socioeconomic fabric hinges on it being a medium for greater amount of data transmission. Briefly, high capacity bandwidth allows greater amount of information to be transmitted which is the essence of all applications and communications. It is widely predicted that Internet through broadband will quickly penetrate the residential markets that is in line with the National Broadband Plan (NBP) that focuses on infrastructure readiness and market penetration, expediting the rollout of broadband using both fixed and wireless access. The first in the list of 10 National Policy Objectives as stated in the Communications & Multimedia Act (CMA) 1998 reports the aspiration of turning Malaysia into a communications and multimedia global hub. Hashim (2006) states that a secretariat has been formed to roll out the NBP to ensure its success and to achieve the 10% of the population by 2008. Indeed, one of the fundamental strategies to accomplish such a vision is to put in place an efficient broadband network and ensure sufficient subscription to the services. Broadband is different from conventional dial-up services due to its many enhanced capabilities. It provides access to a wide range of Internet services and applications like streaming media, Internet phone, online gaming, and other interactive services. Many of these current and newly developed services are “bandwidth hungry,” thus requiring large amounts of data transfer at excessively fast speed, which may not be technically feasible with dial-up service. Therefore, broadband service may be increasingly necessary to access a full range of services and opportunities beyond what a dial-up service could potentially offer. Many residential customers who have been using traditional dial-up have been migrating to broadband. The constantly connected Internet accessibility remains another lucrative benefit for broadband converts as compared to the dial-up technology. Broadband technology does not block phone lines nor requires one to reconnect to the network after logging off. The dedicated connection for the user translates into less delay in transmission of content. A faster connection speed could allow users to access a wide range of resources, services, and products.

scholarly journals Li-Fi the Next Generation of Wireless Communication through Visible Light Communication (VLC) Technology

2019 ◽  
pp. 30-37 ◽  
Author(s):  
Imran Siddique ◽  
Muhammad Zubair Awan ◽  
Muhammad Yousaf Khan ◽  
Azhar Mazhar
Keyword(s):  
Wireless Communication ◽  
Visible Light ◽  
Communication System ◽  
High Speed ◽  
Wave Spectrum ◽  
Visible Light Communication ◽  
Visible Light Communications ◽  
Light Emitting ◽  
Wide Range ◽  
Advance Research

Li-Fi stands for Light-Fidelity. This technology is very new and was proposed by the German physicist Harald Haas in 2011. Light based communication system is the backbone of the future of the communication system. Li-Fi is a wireless technology that uses light emitting diodes (LEDs) for transmission of data. The development of the wireless communication leads to advance research in LiFi technology. The term Li-Fi states to visible light communication (VLC) technology that uses as medium to deliver high-speed communication in a fashion similar to Wi-Fi. Li-Fi comprises a wide range of frequencies and wavelengths, from the Infrared through visible and down to the Ultraviolet spectrum. The immense use of Li-Fi may solve some bottleneck of data transmission in Wi-Fi technology. With the innovation in technology and the number of users, the existing radio-wave spectrum fails to accommodate this need. To resolve the issues of scalability, availability and security, we have come up with the concept of transmitting data wirelessly through light using visible light communication (VLC) technology. This paper objective is to study and describe the LiFi technology. The improvement of the wireless communication leads to advance research in LiFi technology through Visible Light Communications (VLC) Technology.

Numerical Modeling of a Planing Hull Maneuvering in Full Scale Trail

2015 ◽  
Author(s):  
Ray-Qing Lin ◽  
Susan Brewton ◽  
George S. Hazen ◽  
Damien Bretall
Keyword(s):  
High Speed ◽  
High Performance ◽  
Dynamic Balance ◽  
High Capacity ◽  
Ship Motion ◽  
Motion Model ◽  
Planing Craft ◽  
Wide Range ◽  
Target Track ◽  
Flexible Tubes

The high-speed Rigid Hulled Inflatable Boat (RHIB) is one of the key forms of transportation for the U.S. Navy in littoral regions. This planing craft, shown in Figure 1, is a lightweight, high-performance, high-capacity boat. It is constructed with a solid, shaped hull and flexible tubes at the gunwale. The flexible tubes maintain a high buoyancy to avoid capsize in bad seas and to better absorb heavy loads. When the RHIB maneuvers in a seas state greater than 2, however, it often gets off plane or jumps to an entirely different heading regardless of the craft speed and heading relative to the direction of wave propagation. This behavior may cause the planing boat to miss its target track and veer off course. Furthermore, if a RHIB is supporting shore facilities or large ships transporting troops, the deviations and jumps may also impact the safety of the troops. In order to shine a light on improving the RHIB planing craft design for better performance at higher sea states, this study used a fully-nonlinear ship motion model named the Digital Self consistent Ship Experimental Laboratory (DiSSEL) by Lin and Kuang (2011a and 2011b) as a numerical tool to examine the dynamic balance of a six-degree-freedom (6DOF) RHIB. First the RHIB is maneuvered in Seas State 2, then in Seas State 3. The results of the simulation serve to better understand the underlying physics that cause dynamics instability at higher sea states. This study also serves to validate the accuracy of the DiSSEL ship motion model with observational data of a 10-meter long RHIB at Seas State 2. The model shows good agreement with experimental data in all headings and with a wide range of boat speeds (up to Froude number of 1.265).

Microfabrication research at the National Submicron Facility

1983 ◽  
Vol 41 ◽  
pp. 86-89
Author(s):  
E.D. Wolf
Keyword(s):  
Integrated Circuits ◽  
Particle Physics ◽  
High Speed ◽  
New Technology ◽  
High Energy ◽  
High Energy Particle ◽  
New Science ◽  
Wide Range ◽  
Intermediate Domain ◽  
Circuit Function

Most microelectronics devices and circuits operate faster, consume less power, execute more functions and cost less per circuit function when the feature-sizes internal to the devices and circuits are made smaller. This is part of the stimulus for the Very High-Speed Integrated Circuits (VHSIC) program. There is also a need for smaller, more sensitive sensors in a wide range of disciplines that includes electrochemistry, neurophysiology and ultra-high pressure solid state research. There is often fundamental new science (and sometimes new technology) to be revealed (and used) when a basic parameter such as size is extended to new dimensions, as is evident at the two extremes of smallness and largeness, high energy particle physics and cosmology, respectively. However, there is also a very important intermediate domain of size that spans from the diameter of a small cluster of atoms up to near one micrometer which may also have just as profound effects on society as “big” physics.

Extending the Applicability of the ANI Deep Learning Molecular Potential to Sulfur and Halogens

2020 ◽  
Author(s):  
Christian Devereux ◽  
Justin Smith ◽  
Kate Davis ◽  
Kipton Barros ◽  
Roman Zubatyuk ◽  
...  
Keyword(s):  
Drug Development ◽  
Autonomous Vehicles ◽  
Potential Energy Surfaces ◽  
Organic Molecules ◽  
Chemical Elements ◽  
Molecular Potential ◽  
Wide Range ◽  
Energy Surfaces ◽  
New Applications ◽  
Physical Phenomena

<p>Machine learning (ML) methods have become powerful, predictive tools in a wide range of applications, such as facial recognition and autonomous vehicles. In the sciences, computational chemists and physicists have been using ML for the prediction of physical phenomena, such as atomistic potential energy surfaces and reaction pathways. Transferable ML potentials, such as ANI-1x, have been developed with the goal of accurately simulating organic molecules containing the chemical elements H, C, N, and O. Here we provide an extension of the ANI-1x model. The new model, dubbed ANI-2x, is trained to three additional chemical elements: S, F, and Cl. Additionally, ANI-2x underwent torsional refinement training to better predict molecular torsion profiles. These new features open a wide range of new applications within organic chemistry and drug development. These seven elements (H, C, N, O, F, Cl, S) make up ~90% of drug like molecules. To show that these additions do not sacrifice accuracy, we have tested this model across a range of organic molecules and applications, including the COMP6 benchmark, dihedral rotations, conformer scoring, and non-bonded interactions. ANI-2x is shown to accurately predict molecular energies compared to DFT with a ~10<sup>6</sup> factor speedup and a negligible slowdown compared to ANI-1x. The resulting model is a valuable tool for drug development that can potentially replace both quantum calculations and classical force fields for myriad applications.</p>

scholarly journals Exploring Suppliers’ Approaches toward Workplace Safety Compliance in the Global Garment Sector: From Bangladesh Perspective

2021 ◽  
Vol 10 (3) ◽  
pp. 90
Author(s):  
Md Sultan Mahmood ◽  
Nilima Haque Ruma ◽  
Toufiq Ahmed ◽  
Yukari Nagai
Keyword(s):  
Case Study Research ◽  
Code Of Conduct ◽  
Workplace Safety ◽  
Research Strategy ◽  
Social Needs ◽  
Health Issues ◽  
Labor Laws ◽  
Wide Range ◽  
Safety Compliance ◽  
Health Rights

The readymade garment (RMG) sector is one of the main drivers of the Bangladesh economy with over 4 million employed. In the 2013 Rana Plaza accident aftermath, the implementation of workplace safety compliance (WSC) became imperative. The paper investigated the WSC initiatives implemented by the RMG sector to overcome safety challenges and their effectiveness for a safe and healthy workplace. We employed a multi-case study research strategy over three Bangladeshi garment manufacturers to resolve these queries. The result revealed that the manufacturers joined in the safety governance programs to protect workers’ health safety rights immediately after the accidents. They participated in inspections and remediations programs over structural, electrical, and fire protection as a priority. Moreover, several other human rights conventions, national labor laws and, buyer code of conduct were also adopted as regulatory and voluntary initiatives to settle workers’ health rights and social needs. The WSC enforcement empowered workers to bargain their rights toward a safe workplace and made them responsible for responding during an emergency. Finally, the paper argues that the WSC in the RMG sector nowadays covers a wide range of initiatives in three broad areas: physical environment safety, workers’ health issues, and workers’ rights.

Assessment of Commercial Off-the-Shelf Tissue Adhesives for Sealing Military-Relevant Corneal Perforation Injuries

2021 ◽  
Author(s):  
Eric J Snider ◽  
Lauren E Cornell ◽  
Brandon M Gross ◽  
David O Zamora ◽  
Emily N Boice
Keyword(s):  
Intraocular Pressure ◽  
High Speed ◽  
Anterior Segment ◽  
Ocular Tissue ◽  
Corneal Tissue ◽  
Corneal Perforation ◽  
Tissue Adhesives ◽  
Open Globe ◽  
Wide Range ◽  
Commercial Off The Shelf

ABSTRACT Introduction Open-globe ocular injuries have increased in frequency in recent combat operations due to increased use of explosive weaponry. Unfortunately, open-globe injuries have one of the worst visual outcomes for the injured warfighter, often resulting in permanent loss of vision. To improve visual recovery, injuries need to be stabilized quickly following trauma, in order to restore intraocular pressure and create a watertight seal. Here, we assess four off-the-shelf (OTS), commercially available tissue adhesives for their ability to seal military-relevant corneal perforation injuries (CPIs). Materials and Methods Adhesives were assessed using an anterior segment inflation platform and a previously developed high-speed benchtop corneal puncture model, to create injuries in porcine eyes. After injury, adhesives were applied and injury stabilization was assessed by measuring outflow rate, ocular compliance, and burst pressure, followed by histological analysis. Results Tegaderm dressings and Dermabond skin adhesive most successfully sealed injuries in preliminary testing. Across a range of injury sizes and shapes, Tegaderm performed well in smaller injury sizes, less than 2 mm in diameter, but inadequately sealed large or complex injuries. Dermabond created a watertight seal capable of maintaining ocular tissue at physiological intraocular pressure for almost all injury shapes and sizes. However, application of the adhesive was inconsistent. Histologically, after removal of the Dermabond skin adhesive, the corneal epithelium was removed and oftentimes the epithelium surface penetrated into the wound and was adhered to inner stromal tissue. Conclusions Dermabond can stabilize a wide range of CPIs; however, application is variable, which may adversely impact the corneal tissue. Without addressing these limitations, no OTS adhesive tested herein can be directly translated to CPIs. This highlights the need for development of a biomaterial product to stabilize these injuries without causing ocular damage upon removal, thus improving the poor vision prognosis for the injured warfighter.

scholarly journals Observation and analysis of diving beetle movements while swimming

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Debo Qi ◽  
Chengchun Zhang ◽  
Jingwei He ◽  
Yongli Yue ◽  
Jing Wang ◽  
...  
Keyword(s):  
Swimming Speed ◽  
High Speed ◽  
Kinematic Model ◽  
Movement Pattern ◽  
Unmanned Vehicles ◽  
Power Stroke ◽  
Cross Sectional ◽  
Motion Data ◽  
The Cross ◽  
Diving Beetle

AbstractThe fast swimming speed, flexible cornering, and high propulsion efficiency of diving beetles are primarily achieved by their two powerful hind legs. Unlike other aquatic organisms, such as turtle, jellyfish, fish and frog et al., the diving beetle could complete retreating motion without turning around, and the turning radius is small for this kind of propulsion mode. However, most bionic vehicles have not contained these advantages, the study about this propulsion method is useful for the design of bionic robots. In this paper, the swimming videos of the diving beetle, including forwarding, turning and retreating, were captured by two synchronized high-speed cameras, and were analyzed via SIMI Motion. The analysis results revealed that the swimming speed initially increased quickly to a maximum at 60% of the power stroke, and then decreased. During the power stroke, the diving beetle stretched its tibias and tarsi, the bristles on both sides of which were shaped like paddles, to maximize the cross-sectional areas against the water to achieve the maximum thrust. During the recovery stroke, the diving beetle rotated its tarsi and folded the bristles to minimize the cross-sectional areas to reduce the drag force. For one turning motion (turn right about 90 degrees), it takes only one motion cycle for the diving beetle to complete it. During the retreating motion, the average acceleration was close to 9.8 m/s2 in the first 25 ms. Finally, based on the diving beetle's hind-leg movement pattern, a kinematic model was constructed, and according to this model and the motion data of the joint angles, the motion trajectories of the hind legs were obtained by using MATLAB. Since the advantages of this propulsion method, it may become a new bionic propulsion method, and the motion data and kinematic model of the hind legs will be helpful in the design of bionic underwater unmanned vehicles.

scholarly journals Vibration of Rotating and Revolving Planet Rings with Discrete and Partially Distributed Stiffnesses

2020 ◽  
Vol 11 (1) ◽  
pp. 127
Author(s):  
Fuchun Yang ◽  
Dianrui Wang
Keyword(s):  
High Speed ◽  
Differential Operators ◽  
Natural Frequencies ◽  
Rotation Speed ◽  
Distribution Area ◽  
Vibration Modes ◽  
Governing Equations ◽  
Vibration Properties ◽  
Wide Range ◽  
Forced Responses

Vibration properties of high-speed rotating and revolving planet rings with discrete and partially distributed stiffnesses were studied. The governing equations were obtained by Hamilton’s principle based on a rotating frame on the ring. The governing equations were cast in matrix differential operators and discretized, using Galerkin’s method. The eigenvalue problem was dealt with state space matrix, and the natural frequencies and vibration modes were computed in a wide range of rotation speed. The properties of natural frequencies and vibration modes with rotation speed were studied for free planet rings and planet rings with discrete and partially distributed stiffnesses. The influences of several parameters on the vibration properties of planet rings were also investigated. Finally, the forced responses of planet rings resulted from the excitation of rotating and revolving movement were studied. The results show that the revolving movement not only affects the free vibration of planet rings but results in excitation to the rings. Partially distributed stiffness changes the vibration modes heavily compared to the free planet ring. Each vibration mode comprises several nodal diameter components instead of a single component for a free planet ring. The distribution area and the number of partially distributed stiffnesses mainly affect the high-order frequencies. The forced responses caused by revolving movement are nonlinear and vary with a quasi-period of rotating speed, and the responses in the regions supported by partially distributed stiffnesses are suppressed.

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