Aerospace Engineering Commons^™

The Effect Of Through Thickness Reinforcement On Debonding Behavior Of Skin/Stringer Configuration, Yogaraja Sridhar

Mechanical & Aerospace Engineering Theses & Dissertations

Investigation of this study is to the determine the crack propagation and disbonding in the bonded region of the skin and stringer specimen. An adhesive layer has been used to bond the skin and stringer by using a heat press operation. After the bonding, a drilling method has been adopted to install the through thickness reinforcement in the specimen. The key role of the through thickness reinforcement is to increase the stiffness and strength of the panels and to prevent the crack propagation or disbonding of the panels. The reinforcement was installed in pure (Pristine) samples and in defect samples …

A Digital One Degree Of Freedom Model Of An Electromagnetic Position Sensor, Michelle Elizabeth Weinmann

Mechanical & Aerospace Engineering Theses & Dissertations

The purpose of this project was to improve an existing system currently in use by NASA Langley Research Center (LaRC). The 6-inch Magnetic Suspension and Balance System (MSBS) built at MIT is operational with control in three degrees of freedom, with two additional degrees of freedom exhibiting passive stability. The means for measuring model displacement within the magnetic environment is an Electromagnetic Position Sensor (EPS), consisting of excitation coils at 20 kHz and multiple sets of pickup coils. The pickup coil voltages are proportional to model displacement in each degree of freedom. However, the EPS electronic signal processing system is …

Development And Applications Of Adjoint-Based Aerodynamic And Aeroacoustic Multidisciplinary Optimization For Rotorcraft, Ramiz Omur Icke

Mechanical & Aerospace Engineering Theses & Dissertations

Urban Air Mobility (UAM) is one of the most popular proposed solutions for alleviating traffic problems in populated areas. In this context, the proposed types of vehicles mainly consist of rotors and propellers powered by electric motors. However, those rotary-wing components can contribute excessively to noise generation. Therefore, a significant noise concern emerges due to urban air vehicles in or around residential areas. Reducing noise emitted by air vehicles is critically important to improve public acceptance of such vehicles for operations in densely populated areas.

Two main objectives of the present dissertation are: (1) to expand the multidisciplinary optimization to …

Additively Manufactured Dielectric Elastomer Actuators: Development And Performance Enhancement, Stanislav Sikulskyi

Doctoral Dissertations and Master's Theses

The recently emerging and actively growing areas of soft robotics and morphing structures promise endless opportunities in a wide range of engineering fields, including biomedical, industrial, and aerospace. Soft actuators and sensors are essential components of any soft robot or morphing structure. Among the utilized materials, dielectric elastomers (DEs) are intrinsically compliant, high energy density polymers with fast and reversible electromechanical response. Additionally, the electrically driven work principle allows DEs to be distributed in a desired fashion and function locally with minimum interference. Thus, a great effort is being made towards utilizing additive manufacturing (AM) technologies to fully realize the …

Issue 7: Contributors, David Hartshorn, Martin Jarrold

Online Journal of Space Communication

List of Issue 7 Contributors.

Future Solutions: Access To Ict: A Tale Of Three Briefings, David Hartshorn

Online Journal of Space Communication

If your inbox is anything like mine, then you already know that the publication of satellite communications reports has become an industry unto itself. But that's not to say that it's always an end unto itself. On the contrary.

Future Solutions: Universal Access, David Hartshorn

Online Journal of Space Communication

Today, the nations of the world have an immediate opportunity to advance essential telecommunication policy objectives through harmonisation of regulations governing the use of fixed satellite-based network solutions.

Regulatory Reform: Strengthening Access To Information & Communications Technologies: Guidelines To Facilitate Policy & Regulation For Satellite Services, Global Vsat Forum

Online Journal of Space Communication

This document was prepared by GVF, an association of organisations engaged in the delivery of advanced broadband and narrowband satellite services to consumers, and commercial and government enterprises worldwide.

Regulatory Reform: In The Land Of The 'Coffeenet', Martin Jarrold

Online Journal of Space Communication

Sitting down to write this article at a desk some 30 miles south of central London, and less than one degree west of the Greenwich meridian, I became immediately more conscious than usual of geography. The frequently interwoven use of such western-centric cartographic labels as Middle East, and Far East, with the geographically more precise terms of Western or Central Asia, and East and South-East Asia, sometimes causes us to confuse the actual proximity of Europe's, much larger, near-neighbour.

Regulatory Reform: Asia's Great Step Forward, David Hartshorn

Online Journal of Space Communication

This paper was presented at Connect-World Asia Pacific, June 2002.

Forget about a great leap forward. All that's needed to facilitate communications in Asia are a few small steps. Indeed, today all nations of the world have an immediate opportunity to advance essential telecommunication policy objectives through harmonisation of regulations governing the use of telecommunications solutions.

Regulatory Reform: Wanted: A Bridge For Africa's Digital Divide Apply: Pretty Much Anywhere In Africa Quote Reference: Vsat, Martin Jarrold

Online Journal of Space Communication

For Africa, and for the economy of the whole planet, those hundreds of millions of people across the continent who are currently denied reasonable access to even simple voice service represent a vast untapped pool of creativity. This very large and potentially very powerful economic dynamo demands access to more than the simplest tools of communication, and requires the means to unleash the potential productivity of its own knowledge-base into an increasingly connected world. The International Telecommunications Union acknowledges this, as does its sister organisation, the United Nations. The Global VSAT Forum enjoins you to acknowledge it too.

Overview: A+B+C = Vsat, Martin Jarrold

Online Journal of Space Communication

The benefits of VSAT systems and services are being realised in all spheres across the globe, both private and public. Banks, government departments, schools, hospitals, home offices, small enterprises, multi-national corporates, and rural telephony… all sectors are seizing upon the opportunity to get connected through satellite communications.

Overview: Satellite Communication In Ghana - Challenges And Prospects, Kwasi Boateng

Online Journal of Space Communication

Busy Internet is a Ghanaian ISP that uses satellite connectivity to bring Internet to West Africans. The operations of this ISP illustrate the reliability, versatility and efficiency of, VSAT, (Very Small Aperture Terminal) networks in delivering fast broadband Internet services.

Overview: The View From 22,300 Miles High, David Hartshorn

Online Journal of Space Communication

Asia's geography, claiming many of the world's highest peaks, has provided a dramatic setting for a climbing expedition that began decades ago, when the satellite communications community took its first step on the lower slopes of the mountain.

Overview: Politics And Technology Converge: Case Studies On The Effects Of Regulatory Reform On Vsat Adoption In Developing Countries, Emmanuel Adugu, Kwasi Boateng, D. Flournoy, Eric Gavua, Wencelous Kaswoswe, Miao Zhang

Online Journal of Space Communication

Developing countries are actively implementing satellite data networks, and have undertaken policy reforms to facilitate such networks. This research examines how regulatory changes have resulted in the removal of barriers relating to the deployment of access technologies and growth in connectivity, especially in VSAT installations for low cost Internet access. In addition, this research seeks to identify the socio-economic impact of emerging data network applications in government, business, health and education. In some cases, government offices have been the driver of change; in other cases, businesses have been the ones to initiate and press these developments forward.

Overview: Pipelines Of The Skies, Errol Olivier

Online Journal of Space Communication

Advances in fixed satellite technology are enabling oil and gas concerns to enhance the efficiency of offshore operations with cost-effective voice and data network solutions.

Issue 7: From The Guest Editors, David Hartshorn, Martin Jarrold

Online Journal of Space Communication

During the past 15 years, the international satellite communications industry has been developing and refining network solutions such that today, there are more than one million so-called Very Small Aperture Terminal (VSAT) systems installed and operating in more than 120 countries.

Space And Defense – Volume Twelve – Number One – Winter 2021, Space And Defense Journal

Space and Defense

No abstract provided.

Fluid-Structure Interaction Of Nrel 5-Mw Wind Turbine, Mohamed Sayed Elkady Abd-Elhay

Theses and Dissertations

Wind energy is considered one of the major sources of renewable energy. Nowadays, wind turbine blades could exceed 100 m to maximize the generated power and minimize produced energy cost. Due to the enormous size of the wind turbines, the blades are subjected to failure by aerodynamics loads or instability issues. Also, the gravitational and centrifugal loads affect the wind turbine design because of the huge mass of the blades. Accordingly, wind turbine simulation became efficient in blade design to reduce the cost of its manufacturing. The fluid-structure interaction (FSI) is considered an effective way to study the turbine's behavior …

Transport-Based Pattern Recognition Versus Deep Neural Networks In Underwater Oam Communications, Patrick L. Neary, Jonathan M. Nichols, Abbie T. Watnik, K. Peter Judd, Gustavo K. Rohde, James R. Lindle, Nicholas S. Flann

Space Dynamics Laboratory Publications

Comparisons between machine learning and optimal transport-based approaches in classifying images are made in underwater orbital angular momentum (OAM) communications. A model is derived that justifies optimal transport for use in attenuated water environments. OAM pattern demultiplexing is performed using optimal transport and deep neural networks and compared to each other. Additionally, some of the complications introduced by signal attenuation are highlighted. The Radon cumulative distribution transform (R-CDT) is applied to OAM patterns to transform them to a linear subspace. The original OAM images and the R-CDT transformed patterns are used in several classification algorithms, and results are compared. The …

Satellite Security And Performance In An Era Of Dual Use, Joseph N. Pelton

Online Journal of Space Communication

Since the mid-1990s the U.S. Government and military forces have placed more and more reliance on commercial satellite systems for military communications of a non-tactical nature. Requirements such as the U.S. Armed Forces Radio and Television require a great deal of bandwidth but do not require any special security protection. Further there are many other forms of communications involving national security or defense systems where a varying degree of security is required. Many of these applications do not require a very high level of "top secret" protection since these communications do involve tactical, strategic or highly classified messages. For instance, …

International Guidelines For The Preservation Of Space As A Unique Resource, Phillip D. Anz-Meador

Online Journal of Space Communication

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Overview: Satellite Signal Security: Copyright Protection Korean Dbs Content And Transaction Security, Don Flournoy

Online Journal of Space Communication

As a result of new developments in broadband communication, residential users, office workers and those who move from place to place have more ways to access the programming and services they want when they want them.

Space-Based Offensive Weapons: Have Policymakers Discussed This Enough?, Kathleen M. Sweet

Online Journal of Space Communication

Arguably, one of the most significant global security policy debates of the 21st century is whether the United States and more specifically the Bush Administration should develop and deploy space-based weaponry. The age of space is upon us. But how convinced is the rest of America, the West and potential adversaries of the legitimate need to do so? For almost half a century, the world's space powers have abstained from deploying such weapons as basic unwritten policy. To date, the military has been limited to surveillance, navigation and communications satellites

Overview: Space Security: Possible Issues And Potential Solutions, Ziad I. Akir

Online Journal of Space Communication

Space communication has become an integral component of our overall global telecommunication infrastructure. Satellites are being used for telecommunication, business, entertainment, education, Internet, navigation, remote sensing, imaging, and weather forecasting.

Satellites are also providing backup communication capabilities when terrestrial communication is interrupted in cases such as earthquakes or other natural (or unnatural) disasters. The September 11th events in 2001 demonstrated the value of redundant satellite systems in supporting rescue efforts.

Overview: The Increasing Threat To Satellite Communications, Sean Patrick Bain

Online Journal of Space Communication

Communication security has been a priority since the beginning of recorded history. The survival of human cultures has always relied on the use of accurate information transported over distances. The interception of this information, preventing its reception or its misuse, can alter the course of nations. As technology advances, so too does the threat to modern satellite communication. The methods of interfering with or intercepting satellite signals are numerous and need to be better understood.

As has been demonstrated by a small team of undergraduate students, the capability to intercept the nation's communication satellite signals is no longer limited to …

Issue 6: From The Guest Editor, Kathleen Sweet

Online Journal of Space Communication

Guest editor introduction.

Structural Reform For It Competitiveness In Japan, Kei Hata

Online Journal of Space Communication

Five years ago, in order to publicize the necessity for the Japanese government to have an Information Technology policy that until then was largely ignored, as a member of the House of Counselors of the Japanese Diet, I created an urgent proposal and presented it to Prime Minister Hashimoto.

Issue 5: Contributors, Bruce Elbert

Online Journal of Space Communication

List of issue 5 contributors.

Bridging The Digital Divide: Towards A New Paradigm, Virgil Labrador

Online Journal of Space Communication

My direct experience in the "digital divide" was when I was marketing director for a band-new state-of-the-art program origination and satellite transmission facility in Singapore seven years ago in 1996. Our first and anchor client was the highly successful Discovery Network--which housed in our facility the first all-digital channel to the Asia-Pacific market.