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Endorsement Of Automatic Dependent Surveillance-broadcast Data For Monitoring RVSM Aircraft Altimetry System Error

1. INTRODUCTION

1.1 The Separation and Airspace Safety Panel (SASP) and Asia/Pacific Regional Airspace Safety Monitoring Advisory Group (RASMAG) has strongly encouraged work to continue that would assess the viability of using ADS-B geometric height data as a means of estimating altimetry system error (ASE). This work has been progressed jointly by Australia (represented by Airservices Australia) and the United States (represented by the FAA) under the terms of a formally recognized research project, that initially utilised data available from the extensive ADS-B network in Australia, and the software and expertise available in the United States used for estimating ASE.

1.2 At previous meetings of the SASP and RASMAG, Australia and the United States had presented papers that described further development work on the use on ADS-B for RVSM height-keeping performance monitoring. In particular, the papers provided an explanation for the variations in ASE for the same aircraft observed at different ADS-B stations. The research had determined that if in...

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A Core Algorithm for Object Tracking and Monitoring via Distributed Wireless Sensor Networks

Abstract We consider object tracking and monitoring implemented via the use of distributed wireless sensor net- works. We view the signal processing and communications operations performed in such networks, in conjunction with the time constraints imposed on their signal processing objectives and the limited life-spans of their sensors. We identify some of the object identification and network monitoring functions that are embedded in such systems. We subsequently focus on a core algorithm whose various manifestations may serve effectively a variety of network functions, and propose its novel application for image and sound object tracking. We also propose a new distributed version of the algorithm for the monitoring of data rates in the network.

1 Introduction
Object tracking and monitoring is currently extensively implemented by distributed wireless sensor networks whose architectures, operations, and performance demands are dictated by the tracking and monitoring objectives, but are also constrained by the characteristics and limitations of the environment. Within the statistical inference domain, the tracking and monitoring

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Missile Trajectory Shaping Using Sampling-Based Path Planning

Abstract

This paper presents missile guidance as a complex robotic problem: a hybrid non-linear system moving in a heterogeneous environment. The proposed solution to this problem combines a sampling-based path planner, Dubins’ curves and a locally-optimal guidance law. This algorithm aims to find feasible trajectories that anticipate future flight conditions, especially the loss of manoeuverability at high altitude. Simulated results demonstrate the substantial performance improvements over classical midcourse guidance laws and the benefits of using such methods, well-known in robotics, in the missile guidance field of research.

INTRODUCTION

The purpose of this paper is to define a new guidance algorithm for an endoatmospheric interceptor missile which aims to destroy a flying target. The guidance of an interceptor toward a target is illustrated in figure 1. It is divided into two different phases. The first one, called midcourse guidance, starts at the interceptor launch...

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A Numerical Model For Ocean Ultra-low Frequency Noise: Wave-generated Acoustic-Gravity And Rayleigh Modes

I. INTRODUCTION

Ultra-low frequency acoustic noise (ULF, 0.1 to 1 Hz) has been observed from shallow water to all depths of the deep ocean.2,3 At large depths, noise has been associated with seismic pseudo-Rayleigh waves that propagate over thousands of kilometers,3,4 from oceans to land. The term “pseudo-Rayleigh” is also used for the same modes generated by earthquakes, and it emphasizes the effect of the water layer in which the motion is a superposition of obliquely propagating sound waves.5 In the crust, the amplitude of motion decays with depths, similar to usual Rayleigh waves, with a combination of shear and compression waves that gives zero tangential stress on the ocean bottom. For simplicity we will omit the “pseudo” and, even in the oceans, we will use the term “Rayleigh” waves. These waves propagate slower than the shear wave speed in the crust and usually faster than the speed of sound in water. These are clearly seismo-acoustic waves that propagate from oceans to land,

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The Advantages of Row and Rack Oriented Cooling Architectures for Data Centers

Introduction

All of the electrical power delivered to the IT loads in a data center ends up as waste heat hat must be removed to prevent over temperature conditions. Virtually all IT equipment is air-cooled, that is, each piece of IT equipment takes in ambient air and ejects waste heat into its exhaust air. Since a data center may contain thousands of IT devices, the result is that there are thousands of hot airflow paths within the data center that together represent the total waste heat output of the data center; waste heat that must be removed. The purpose of the air conditioning system for the data center is to efficiently capture this complex flow of waste heat and eject it from the room. Room-based cooling is the historical method for accomplishing data center cooling. In this approach, one or more air conditioning systems, working in parallel, push cool air into the data center while drawing out warmer ambient air. The basic principle of this approach is that...

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High Speed Serial I/O Made Simple

Introduction

An overview of digital I/O signal processing methods
I/O Performance Limitations Input/output (I/O) has always played a crucial role in computer and industrial applications. But as signal processing became more sophisticated, problems arose that prevented reliable I/O communication. In early parallel I/O buses, interface alignment problems prevented effective communication with outside devices. And as higher speeds became prevalent in digital design, managing signal delays became problematic.

Digital Design Solutions for I/O
Digital designers turned to a host of methods to increase signal speed and eliminate I/O problems. For example, differential signal processing was employed to increase speed in chip-to-chip communications. And design methods such as signal-, source-, and self-synchronization refined inter-IC (integrated circuit) communication to provide reliable I/O at speeds demanded by the computer industry.

Introducing Multi-Gigabit Serial
Figure 1-1 shows a typical digital signal.

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Remotely Interested? Observing Television Viewers’ Advertising-Related Behavior

Consumer Control

The activity of “watching television” is so familiar that it’s easy to underestimate the complexity hidden by the simple answer to the traditional media researcher’s question. Imagine a timeline that maps this hypothetical evening spent watching TV from 8:00 p.m. to 10:00 p.m.:

The timeline is an accurate map of the respondent’s answer, but we know there’s much more to the experience than just “watching TV.” Considering just the stream of content delivered via the person’s television screen, we can acknowledge at least two major categories: program (of any genre) and advertisements (including program promotions). The average amount of advertising and promotional material in each hour of TV programming is 14.8 minutes, although there is considerable variation by network, program, and time of day (MindShare, 2006). If we map these content categories onto the timeline, the result might look something like this:

There’s yet another influence on the viewer’s exposure to program content and ad pods: It’s unlikely our respondent sat down and watched...

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CISCO IP Networks for Broadcaster Applications

Introduction

The future of communications is here, and its name is Internet Protocol (IP). Originally regarded as an IT-only transport technology suitable for data and email traffi c, IP has quickly become the dominant standard for all types of communications. This change is largely due to the inherent fl exibility of IP transport, its cost efficiencies, and the ubiquitous availability of IP networks. Despite these advantages, however, until recently broadcasters have not considered IP ready to support “mission critical” real-time video services. While IP networks have played a role in contribution and production processes, they typically were reserved for non-real-time applications. Today, IP network technology has evolved, and concerns about its ability to support the stringent quality and resiliency demands of real-time video have been addressed. As a result, IP is emerging as an increasingly important technology for broadcasters and service providers, and IP-based transport networks and medianets are now used by broadcasters around the globe. The advantages of IP extend beyond operational expense (OPEX)...

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CBS Broadcasting, Inc. And Writers Guild Of America, East, Inc.

II. The Alleged Unfair Labor Practices

A. The Facts

1. Background

Since 1958 WGAE and WGW have been the joint collective-bargaining representatives of a single nationwide unit of CBS newswriters, editors and other employees located in New York, Chicago, Washington and Los Angeles. The most recent collective-bargaining agreement is effective from April 2, 2002 through April 1, 2005.

2. Current Collective-Bargaining Agreement

Negotiations for the current collective-bargaining agreement began on March 6, 2002.2 CBS submitted Proposal 7, which dealt with consolidation of operations. CBS was contemplating the acquisition of KCAL-TV, which would create a “duopoly” in the Los Angeles market. A duopoly is the ownership by a single entity of two television stations in the same television market. Leon Shulzinger, Vice-President of CBS, explained to the Unions’ bargaining committee that since CBS already owned KCBS, it needed to settle arrangements as to WGA covered employees at KCBS with non-covered employees at KCAL. The Unions rejected Proposal 7. At subsequent negotiating sessions Proposal 7 was ...

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