The Experts below are selected from a list of 303 Experts worldwide ranked by ideXlab platform

Cheng Ping-hui - One of the best experts on this subject based on the ideXlab platform.

Melanie N. Ott - One of the best experts on this subject based on the ideXlab platform.

  • Fiber Optic Cable thermal preparation to ensure stable operation
    Optical Technologies for Arming Safing Fuzing and Firing IV, 2008
    Co-Authors: William J. Thomes, Melanie N. Ott, Richard F. Chuska, Frank Larocca, Robert Switzer, Shawn L. Macmurphy
    Abstract:

    Fiber Optic Cables are widely used in modern systems that must provide stable operation during exposure to changing environmental conditions. For example, a Fiber Optic Cable on a satellite may have to reliably function over a temperature range of -50°C up to 125°C. While the system requirements for a particular application will dictate the exact method by which the Fibers should be prepared, this work will examine multiple ruggedized Fibers prepared in different fashions and subjected to thermal qualification testing. The data show that if properly conditioned the Fiber Cables can provide stable operation, but if done incorrectly, they will have large fluctuations in transmission.

  • Fiber Optic Cable assemblies for space flight: II. Thermal and radiation effects
    Photonics for Space Environments VI, 1998
    Co-Authors: Melanie N. Ott
    Abstract:

    Goddard Space Flight Center is conducting a search for space flight worthy Fiber Optic Cable assemblies that will benefit all projects at all of the NASA centers. This paper is number two in a series of papers being issues as a result of this task to define and quality space grade Fiber Optic Cable assemblies. Though to qualify and use a Fiber Optic Cable in space requires treatment of the Cable assembly as a system, it is very important to understand the design and behavior of its parts. This paper addresses that need, providing information on Cable components shrinkage testing and radiation testing results from recent experiments at Goddard Space Flight Center. This work is an extension of the `lessons learned' reported in the first paper of this series entitled `Fiber Optic Cable Assemblies for Space Flight: Issues and Remedies,' published and presented at the AIAA World Congress in Anaheim CA, on October 15, 1997.

  • Fiber Optic Cable Assemblies for Space Flight Applications: Issues and Remedies
    SAE Technical Paper Series, 1997
    Co-Authors: Melanie N. Ott, Jeannette Plante, Jack J. Shaw, M. Ann Garrison-darrin
    Abstract:

    The following is the first in a series of white papers which will be issued as a result of a task to define and qualify space grade Fiber Optic Cable assemblies. Though to qualify and use a Fiber Optic Cable in space requires treatment of the Cable assembly as a system, it is very important to understand the design and behavior of its parts. These papers will address that need, providing information and "lessons learned" that are being collected in the process of procuring, testing and specifying the final assemblies. This installment covers information on Optical Fiber, coatings, Cable components, design guidelines and limitations, radiation and reliability.

Biswanath Mukherjee - One of the best experts on this subject based on the ideXlab platform.

  • disaster aware submarine Fiber Optic Cable deployment for mesh networks
    Journal of Lightwave Technology, 2016
    Co-Authors: Dawson Ladislaus Msongaleli, Ferhat Dikbiyik, Moshe Zukerman, Biswanath Mukherjee
    Abstract:

    With the increasing social and economic reliance on the Internet and the significant monetary and non-monetary societal cost associated with service interruption, network survivability is an important element in telecommunication network design. A major cause of Internet service interruption is breakage of Fiber-Optic Cables due to man-made or natural disasters such as earthquakes. In addition to the societal cost, there is also cost of repairing damaged Cables paid by the Cable owner. A disaster-resilient submarine Cable deployment can achieve significant cost saving when disaster strikes. In this study, we investigate a disaster-aware submarine Fiber-Optic Cable deployment optimization problem to minimize such expected costs in case of a disaster. While selecting paths for the Cables, our approach aims to minimize the expected cost for both Cable owner and the affected society, considering that submarine Fiber-Optic Cables may break because of natural disasters, subject to limitation of available deployment budget and other constraints. In our approach, localized disaster-unrelated potential disconnection (e.g., due to shark bites) are avoided by providing a backup Cable along with primary Cable. We consider a mesh topology network with multiple nodes located at different sea/ocean shores, submarine Fiber-Optic Cables of irregular shape, and a topography of undersea environment. We present an Integer Linear Program to address the problem, together with illustrative numerical examples. Finally, we validate our approach by applying it to a case study of an existing Cable system in the Mediterranean Sea, and the results show that we can significantly reduce overall expected cost at a slight increase in deployment cost. The results demonstrate a potential saving of billions of US dollars for the society in case of a future disaster. In order to achieve such large savings, Cable companies may require to lay somewhat longer Cables to avoid potential disaster areas, which may increase deployment cost that is relatively smaller compared to potential savings in case of a disaster. Understanding such trade-offs is important for stakeholders, including government agencies, Cable industry, and insurance companies, which may have different objectives, but can work together for the overall benefit of the society.

Van Der Made, Kees Jan - One of the best experts on this subject based on the ideXlab platform.

  • Estimation of the Variation in Specific Discharge Over Large Depth Using Distributed Temperature Sensing (DTS) Measurements of the Heat Pulse Response
    'American Geophysical Union (AGU)', 2019
    Co-Authors: Des Tombe B.f., Bakker M., Smits F.j.c., Schaars Frans, Van Der Made, Kees Jan
    Abstract:

    An approach is presented to determine groundwater flow in unconsolidated aquifers with a heat pulse response test using a heating Cable and a Fiber-Optic Cable. The Cables are installed together using direct push so that the Cables are in direct contact with the aquifer. The temperature response is measured for multiple days along the Fiber-Optic Cable with Distributed Temperature Sensing (DTS). The new approach fits a two-dimensional analytical solution to the temperature measurements, so that the specific discharge can be estimated without knowledge of the position of the Fiber-Optic Cable relative to the heating Cable. Two case studies are presented. The first case study is at a managed aquifer recharge system where Fiber-Optic Cables are inserted 15 m deep at various locations to test the fitting procedure. Similar and relatively large specific discharges are found at the different locations with little vertical variation (0.4–0.6 m/day). The second case study is at a polder, where the water level is maintained 2 m below the surrounding lakes, resulting in significant groundwater flow. The heating and Fiber-Optic Cables are inserted to a depth of 45 m. The specific discharge varies 0.07–0.1 m/day and is significantly larger in a thin layer at 30-m depth. It is shown with numerical experiments that the estimated specific discharge is smoother than in reality due to vertical conduction, but the peak specific discharge is estimated correctly for layers thicker than ∼1.5 m.Water Resource

Kees‐jan Van Der Made - One of the best experts on this subject based on the ideXlab platform.

  • Estimation of the Variation in Specific Discharge Over Large Depth Using Distributed Temperature Sensing (DTS) Measurements of the Heat Pulse Response
    Water Resources Research, 2019
    Co-Authors: Bas F. Des Tombe, Frans Schaars, Frank Smits, Mark Bakker, Kees‐jan Van Der Made
    Abstract:

    An approach is presented to determine groundwater flow in unconsolidated aquifers with a heat pulse response test using a heating Cable and a Fiber-Optic Cable. The Cables are installed together using direct push so that the Cables are in direct contact with the aquifer. The temperature response is measured for multiple days along the Fiber-Optic Cable with Distributed Temperature Sensing (DTS). The new approach fits a two-dimensional analytical solution to the temperature measurements, so that the specific discharge can be estimated without knowledge of the position of the Fiber-Optic Cable relative to the heating Cable. Two case studies are presented. The first case study is at a managed aquifer recharge system where Fiber-Optic Cables are inserted 15 m deep at various locations to test the fitting procedure. Similar and relatively large specific discharges are found at the different locations with little vertical variation (0.4–0.6 m/day). The second case study is at a polder, where the water level is maintained 2 m below the surrounding lakes, resulting in significant groundwater flow. The heating and Fiber-Optic Cables are inserted to a depth of 45 m. The specific discharge varies 0.07–0.1 m/day and is significantly larger in a thin layer at 30-m depth. It is shown with numerical experiments that the estimated specific discharge is smoother than in reality due to vertical conduction, but the peak specific discharge is estimated correctly for layers thicker than ∼1.5 m.