534 research outputs found
Miniature Comet Ice and Dust Experiment (Mini-CIDEX)
This document reports the extent of the progress attained by Lockheed Martin Astronautics (LMA) in the development of equipment designed for the miniature Comet Ice and Dust EXperiment (mini-CIDEX) on NASA contract No. NAS2-14042 from the Ames Research Center (ARC). This report is in two parts. The first part summarizes progress in chronological order. The contents of the first part have been extracted from the monthly reports submitted by LMA to ARC over the duration of the program. The second part is a summary of the designs that were extracted from the mini-CIDEX contract designs and implemented into mission studies performed under different funding but in parallel to the mini- CIDEX contract time period. These second part activities were not performed under contract No. NAS2-14042; however, they are included in this report to show how it was intended that the mini-CIDEX be used on actual mission spacecraft
On Using SysML, DoDAF 2.0 and UPDM to Model the Architecture for the NOAA's Joint Polar Satellite System (JPSS) Ground System (GS)
The JPSS Ground System is a lIexible system of systems responsible for telemetry, tracking & command (TT &C), data acquisition, routing and data processing services for a varied lIeet of satellites to support weather prediction, modeling and climate modeling. To assist in this engineering effort, architecture modeling tools are being employed to translate the former NPOESS baseline to the new JPSS baseline, The paper will focus on the methodology for the system engineering process and the use of these architecture modeling tools within that process, The Department of Defense Architecture Framework version 2,0 (DoDAF 2.0) viewpoints and views that are being used to describe the JPSS GS architecture are discussed. The Unified Profile for DoOAF and MODAF (UPDM) and Systems Modeling Language (SysML), as ' provided by extensions to the MagicDraw UML modeling tool, are used to develop the diagrams and tables that make up the architecture model. The model development process and structure are discussed, examples are shown, and details of handling the complexities of a large System of Systems (SoS), such as the JPSS GS, with an equally complex modeling tool, are describe
How Much Do Fruits and Vegetables Cost?
Federal dietary guidance advises Americans to consume more vegetables and fruits because most Americans do not consume the recommended quantities or variety. Food prices, along with taste, convenience, income, and awareness of the link between diet and health, shape food choices. We used 2008 Nielsen Homescan data to estimate the average price at retail stores of a pound and an edible cup equivalent (or, for juices, a pint and an edible cup equivalent) of 153 commonly consumed fresh and processed fruits and vegetables. We found that average prices ranged from less than 20 cents per edible cup equivalent to more than 2 to $2.50 per day, or approximately 50 cents per edible cup equivalent.food prices, food budgeting, fruit and vegetable consumption, 2010 Dietary Guidelines for Americans, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety,
Architecting Communication Network of Networks for Space System of Systems
The National Aeronautics and Space Administration (NASA) and the Department of Defense (DoD) are planning Space System of Systems (SoS) to address the new challenges of space exploration, defense, communications, navigation, Earth observation, and science. In addition, these complex systems must provide interoperability, enhanced reliability, common interfaces, dynamic operations, and autonomy in system management. Both NASA and the DoD have chosen to meet the new demands with high data rate communication systems and space Internet technologies that bring Internet Protocols (IP), routers, servers, software, and interfaces to space networks to enable as much autonomous operation of those networks as possible. These technologies reduce the cost of operations and, with higher bandwidths, support the expected voice, video, and data needed to coordinate activities at each stage of an exploration mission. In this paper, we discuss, in a generic fashion, how the architectural approaches and processes are being developed and used for defining a hypothetical communication and navigation networks infrastructure to support lunar exploration. Examples are given of the products generated by the architecture development process
Quantum enigma machines and the locking capacity of a quantum channel
The locking effect is a phenomenon which is unique to quantum information
theory and represents one of the strongest separations between the classical
and quantum theories of information. The Fawzi-Hayden-Sen (FHS) locking
protocol harnesses this effect in a cryptographic context, whereby one party
can encode n bits into n qubits while using only a constant-size secret key.
The encoded message is then secure against any measurement that an eavesdropper
could perform in an attempt to recover the message, but the protocol does not
necessarily meet the composability requirements needed in quantum key
distribution applications. In any case, the locking effect represents an
extreme violation of Shannon's classical theorem, which states that
information-theoretic security holds in the classical case if and only if the
secret key is the same size as the message. Given this intriguing phenomenon,
it is of practical interest to study the effect in the presence of noise, which
can occur in the systems of both the legitimate receiver and the eavesdropper.
This paper formally defines the locking capacity of a quantum channel as the
maximum amount of locked information that can be reliably transmitted to a
legitimate receiver by exploiting many independent uses of a quantum channel
and an amount of secret key sublinear in the number of channel uses. We provide
general operational bounds on the locking capacity in terms of other well-known
capacities from quantum Shannon theory. We also study the important case of
bosonic channels, finding limitations on these channels' locking capacity when
coherent-state encodings are employed and particular locking protocols for
these channels that might be physically implementable.Comment: 37 page
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For ourselves and the generations to come : constitutional law in Afghanistan, 1964-2004
In the context of modern Afghan political and legal history, the 1964 and 2004 constitutions were once lauded as promising steps toward the country’s adoption of representative government, constitutionalism, and the equitable rule of law. However, the governments that instituted these documents —the Kingdom of Afghanistan and the Islamic Republic of Afghanistan, respectively— collapsed to political and social instability not long after adopting their constitutions. While historical and political commentary has blamed illiberal governance for the failure of these governments, relatively few projects have studied the 1964 and 2004 constitutions as potential contributors to this breakdown in governance. This thesis takes a comparative legal perspective to study the history of the 1964 and 2004 constitutions, their respective intellectual influences, and their effects on Afghan society in the 20th and 21st centuries. The first chapter centers on the pre-modern legal history of Afghanistan, including geographic and social influences on approaches to governance and the impact of the Barakzai monarchy on Afghan nationhood. The second chapter takes a comparative legal approach to analyze the contents of the 1964 and 2004 constitutions, the institutions both documents created, and their approaches to divesting and consolidating political power. The third chapter studies the practical application of the constitutions through the rule of law, their enumerated positions on religion, and the effect of the War in Afghanistan. This thesis argues that the 1964 and 2004 constitutions were greatly informed by authoritarian policies inherited from pre- and early modern Afghan political systems, particularly the primacy of centralized executive leadership. These practices incentivized autocratic political leadership, disincentivized strong representative governance, and undermined the rule of law under the 1964 and 2004 constitutional frameworks.Middle Eastern Studie
Liposomal Bupivacaine in Total Knee Arthroplasty: Preliminary Results of a Two-Surgeon, Retrospective Study
INTRODUCTION: Liposomal bupivacaine (LB) is a slowly degrading preparation that provides local anesthesia for up to 72 hours. It targets the site directly responsible for pain sensation, with no associated motor blockade. In total knee arthroplasty (TKA), it may have superior outcomes to anesthesia with regional nerve block.
METHODS: Our surgeons began using LB in TKA patients in 2013. All patients following each surgeon’s LB start date were the experimental group. An equivalent number of patients prior to 2013 served as the control group. All control group patients received a preoperative femoral nerve block, and all experimental group patients received peri- and intra-articular LB, delivered intraoperatively. All other surgical and anesthesia interventions were the same. We used retrospective chart review to identify patient demographics, time to first ambulation, time to discharge, and incidence of postoperative nausea and vomiting. We also recorded opioid consumption intraoperatively, in the recovery room, and on the floor.
RESULTS: There were 161 patients in each group. We found no significant difference between the two groups with regard to gender, age, weight, preoperative opioid exposure, side of procedure, type of anesthesia (general vs. spinal), or ASA status. On average, LB patients consumed 29.2% less opioid after leaving the recovery room (p
DISCUSSION AND CONCLUSION: With increasing focus on the cost of TKA, there is strong incentive to manage costs associated with the procedure. Additionally, all patients, regardless of comorbid conditions, can benefit from limited exposure to narcotic pain medication. Our results indicate that LB decreases total systemic opioid requirement, time to first ambulation, and time to discharge from the hospital
Assessing agricultural drought in summer over Oklahoma Mesonet sites using the water-related vegetation index from MODIS.
Agricultural drought, a common phenomenon in most parts of the world, is one of the most challenging natural hazards to monitor effectively. Land surface water index (LSWI), calculated as a normalized ratio between near infrared (NIR) and short-wave infrared (SWIR), is sensitive to vegetation and soil water content. This study examined the potential of a LSWI-based, drought-monitoring algorithm to assess summer drought over 113 Oklahoma Mesonet stations comprising various land cover and soil types in Oklahoma. Drought duration in a year was determined by the number of days with LSWI <0 (DNLSWI) during summer months (June-August). Summer rainfall anomalies and LSWI anomalies followed a similar seasonal dynamics and showed strong correlations (r 2 = 0.62-0.73) during drought years (2001, 2006, 2011, and 2012). The DNLSWI tracked the east-west gradient of summer rainfall in Oklahoma. Drought intensity increased with increasing duration of DNLSWI, and the intensity increased rapidly when DNLSWI was more than 48 days. The comparison between LSWI and the US Drought Monitor (USDM) showed a strong linear negative relationship; i.e., higher drought intensity tends to have lower LSWI values and vice versa. However, the agreement between LSWI-based algorithm and USDM indicators varied substantially from 32 % (D 2 class, moderate drought) to 77 % (0 and D 0 class, no drought) for different drought intensity classes and varied from ∼30 % (western Oklahoma) to >80 % (eastern Oklahoma) across regions. Our results illustrated that drought intensity thresholds can be established by counting DNLSWI (in days) and used as a simple complementary tool in several drought applications for semi-arid and semi-humid regions of Oklahoma. However, larger discrepancies between USDM and the LSWI-based algorithm in arid regions of western Oklahoma suggest the requirement of further adjustment in the algorithm for its application in arid regions
Integrated Network Architecture for NASA's Orion Missions
NASA is planning a series of short and long duration human and robotic missions to explore the Moon and then Mars. The series of missions will begin with a new crew exploration vehicle (called Orion) that will initially provide crew exchange and cargo supply support to the International Space Station (ISS) and then become a human conveyance for travel to the Moon. The Orion vehicle will be mounted atop the Ares I launch vehicle for a series of pre-launch tests and then launched and inserted into low Earth orbit (LEO) for crew exchange missions to the ISS. The Orion and Ares I comprise the initial vehicles in the Constellation system of systems that later includes Ares V, Earth departure stage, lunar lander, and other lunar surface systems for the lunar exploration missions. These key systems will enable the lunar surface exploration missions to be initiated in 2018. The complexity of the Constellation system of systems and missions will require a communication and navigation infrastructure to provide low and high rate forward and return communication services, tracking services, and ground network services. The infrastructure must provide robust, reliable, safe, sustainable, and autonomous operations at minimum cost while maximizing the exploration capabilities and science return. The infrastructure will be based on a network of networks architecture that will integrate NASA legacy communication, modified elements, and navigation systems. New networks will be added to extend communication, navigation, and timing services for the Moon missions. Internet protocol (IP) and network management systems within the networks will enable interoperability throughout the Constellation system of systems. An integrated network architecture has developed based on the emerging Constellation requirements for Orion missions. The architecture, as presented in this paper, addresses the early Orion missions to the ISS with communication, navigation, and network services over five phases of a mission: pre-launch, launch from T0 to T+6.5 min, launch from T+6.5 min to 12 min, in LEO for rendezvous and docking with ISS, and return to Earth. The network of networks that supports the mission during each of these phases and the concepts of operations during those phases are developed as a high level operational concepts graphic called OV-1, an architecture diagram type described in the Department of Defense Architecture Framework (DoDAF). Additional operational views on organizational relationships (OV-4), operational activities (OV-5), and operational node connectivity (OV-2) are also discussed. The system interfaces view (SV-1) that provides the communication and navigation services to Orion is also included and described. The challenges of architecting integrated network architecture for the NASA Orion missions are highlighted
Lunar Relay Satellite Network for Space Exploration: Architecture, Technologies and Challenges
NASA is planning a series of short and long duration human and robotic missions to explore the Moon and then Mars. A key objective of these missions is to grow, through a series of launches, a system of systems infrastructure with the capability for safe and sustainable autonomous operations at minimum cost while maximizing the exploration capabilities and science return. An incremental implementation process will enable a buildup of the communication, navigation, networking, computing, and informatics architectures to support human exploration missions in the vicinities and on the surfaces of the Moon and Mars. These architectures will support all space and surface nodes, including other orbiters, lander vehicles, humans in spacesuits, robots, rovers, human habitats, and pressurized vehicles. This paper describes the integration of an innovative MAC and networking technology with an equally innovative position-dependent, data routing, network technology. The MAC technology provides the relay spacecraft with the capability to autonomously discover neighbor spacecraft and surface nodes, establish variable-rate links and communicate simultaneously with multiple in-space and surface clients at varying and rapidly changing distances while making optimum use of the available power. The networking technology uses attitude sensors, a time synchronization protocol and occasional orbit-corrections to maintain awareness of its instantaneous position and attitude in space as well as the orbital or surface location of its communication clients. A position-dependent data routing capability is used in the communication relay satellites to handle the movement of data among any of multiple clients (including Earth) that may be simultaneously in view; and if not in view, the relay will temporarily store the data from a client source and download it when the destination client comes into view. The integration of the MAC and data routing networking technologies would enable a relay satellite system to provide end-to-end communication services for robotic and human missions in the vicinity, or on the surface of the Moon with a minimum of Earth-based operational support
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