Investigation of Doppler Effects on the Detection of Polyphase Coded Radar Waveforms

Special operations missions often depend on discrete insertion of highly trained soldiers into dangerous territory. To reduce the risk involved in this type of engagement, Low Probability of Detection radar waveforms have been designed specifically to defeat enemy passive radar detectors. These waveforms have been shown to perform well when the Doppler shift is minimal, but their performance degrades dramatically with increased frequency shifts due to Doppler effects. This research compares one known Low Probability of Detection waveform, based on Welti coding, with a radar waveform known to provide Doppler constancy, namely, one based on Frank coding. These waveforms are tested using a non-cooperative square-law passive detector as well as a cooperative matched filter detector for various Doppler shift values. Research conclusions address the question of whether or not the Frank coded waveforms provide better detection capability than Welti coded waveforms at high levels of Doppler shift. Conclusions from this research indicate that there is no advantage to using Frank coded waveforms over Welti coded waveforms. All waveforms behaved the same at increasing Doppler shift levels for each of the detectors

International Military Acquisitions Program Model : A Game Theory Approach

The nations of the world spend a signifi cant portion of their wealth on militaries. Every year,billions of dollars go to recruiting, training, maintaining, and equipping the men and women who serve their countries in uniform. This paper looks into one aspect of military spending, acquiring new equipment and systems. In particular, the research focuses on international cooperation in weapon system development and proposes a model to aid decision makers to decide whether and when to join a joint development program. The main goal is to determine what factors are most important in choosing military acquisitions program partners and then to create a model using those factors that will produce policy recommendations for program cooperation

Supporting Regional Security Forces for Peace and Stability Operations

竹内俊隆教授退職記念論文集In Honor of Prof. Toshitaka TAKEUCH

Supporting Regional Security Forces for Peace and Stability Operations

竹内俊隆教授退職記念論文集In Honor of Prof. Toshitaka TAKEUCH

Technology Mergers and the Market for Corporate Control

Several high-profile academic articles and reports claim to have identified important gaps in current merger enforcement rules, particularly with respect to tech and pharma acquisitions involving nascent and potential competitors—so-called “killer acquisitions” and “kill zones.” As a result of these perceived deficiencies, scholars and enforcers have called for tougher rules, including the introduction of lower merger filing thresholds and substantive changes, such as the inversion of the burden of proof when authorities review mergers and acquisitions in the digital platform industry. Meanwhile, and seemingly in response to the increased political and advocacy pressures around the issue, U.S. antitrust enforcers have recently undertaken several enforcement actions directly targeting such acquisitions. As this paper discusses, however, these proposals tend to overlook the important tradeoffs that would ensue from attempts to decrease the number of false positives under existing merger rules and thresholds. While merger enforcement ought to be mindful of these possible theories of harm, the theories and evidence are not nearly as robust as many proponents suggest. Most importantly, there is insufficient basis to conclude that the costs of permitting the behavior they identify is greater than the costs would be of increasing enforcement to prohibit it

Low cost digital image correlation and strain measurement for geotechnical applications

Particle image velocimetry (PIV), or digital image correlation (DIC), is a widely used technique tomeasure soil displacements and strains in small-scale geotechnical models. Arrays of single-board computers (SBCs) produced by Raspberry Pi, and their associated 8-MP cameras, are being used at the University of Cambridge to capture the images required for DIC analysis. This alternative to more expensive camera set-ups has numerous advantages. A single expensive and large camera can be replaced—at low cost—by multiple cameras, adding flexibility and affordability to any experimental set-up. Traditionally, the alignment of multiple cameras to each other and the referencing to a known coordinate system required painted or machined markers to be located on the observation windows through which the experiments are viewed. This can obstruct localised soil grain displacement measurements in those areas of the model where such markers are placed. To complement the Raspberry Pi camera system, a markerless calibration method was used during image acquisition. This paper outlines the set-up of four of these small computers and associated cameras, provides an overview of the use of themarkerless referencing system and reviews two different experimental apparatus used tomeasure soil displacement and strain.When the cost of additional cabling, connectors and mounting hardware is considered for this system, the total cost to implement was approximately $125 USD per camera plus one-time costs of$175 USD for system peripherals, which represents outstanding value and enables practically all geotechnical laboratories to develop similar capabilities

International Wildlife Law : Understanding and Enhancing Its Role in Conservation

We gratefully acknowledge valuable input by Kees Bastmeijer, Sanja Bogojevic, Jennifer Dubrulle, and Han Somsen.Peer reviewedPublisher PD

Forest fire management, climate change, and the risk of catastrophic carbon losses

Approaches to management of fireprone forests are undergoing rapid change, driven by recognition that technological attempts to subdue fire at large scales (fire suppression) are ecologically and economically unsustainable. However, our current framework for intervention excludes the full scope of the fire management problem within the broader context of fire−vegetation−climate interactions. Climate change may already be causing unprecedented fire activity, and even if current fires are within the historical range of variability, models predict that current fire management problems will be compounded by more frequent extreme fire-conducive weather conditions (eg Fried et al. 2004)