5,415 research outputs found
Compositional Verification for Autonomous Systems with Deep Learning Components
As autonomy becomes prevalent in many applications, ranging from
recommendation systems to fully autonomous vehicles, there is an increased need
to provide safety guarantees for such systems. The problem is difficult, as
these are large, complex systems which operate in uncertain environments,
requiring data-driven machine-learning components. However, learning techniques
such as Deep Neural Networks, widely used today, are inherently unpredictable
and lack the theoretical foundations to provide strong assurance guarantees. We
present a compositional approach for the scalable, formal verification of
autonomous systems that contain Deep Neural Network components. The approach
uses assume-guarantee reasoning whereby {\em contracts}, encoding the
input-output behavior of individual components, allow the designer to model and
incorporate the behavior of the learning-enabled components working
side-by-side with the other components. We illustrate the approach on an
example taken from the autonomous vehicles domain
Study of the Mechanisms of Flux Pinning in Type 2 Superconductors
Flux pinning mechanisms in type-2 semiconductors and specific heat measurements on annealed and deformed pure niobium sample
Aquatic Invasive Species as Hazards on Water Resources and Ecosystems in Texas
Water losses due to invasive species cost Texas hundreds of thousands of acre feet of water per year, water unavailable for instream flows, irrigation and other human uses. Innovative, proactive ecological research and public and policy awareness and education initiatives are instrumental to preventing further invasions and managing existing exotic species impacts in Texas aquatic ecosystems
The role of metaphor in shaping the identity and agenda of the United Nations: the imagining of an international community and international threat
This article examines the representation of the United Nations in speeches delivered by its Secretary General. It focuses on the role of metaphor in constructing a common ‘imagining’ of international diplomacy and legitimising an international organisational identity. The SG legitimises the organisation, in part, through the delegitimisation of agents/actions/events constructed as threatening to the international community and to the well-being of mankind. It is a desire to combat the forces of menace or evil which are argued to motivate and determine the organisational agenda. This is predicated upon an international ideology of humanity in which difference is silenced and ‘working towards the common good’ is emphasised. This is exploited to rouse emotions and legitimise institutional power. Polarisation and antithesis are achieved through the employment of metaphors designed to enhance positive and negative evaluations. The article further points to the constitutive, persuasive and edifying power of topic and situationally-motivated metaphors in speech-making
Nondisclosure as a Contract Remedy: Explaining the Advance-notice Puzzle
Prior theoretical work predicts an underprovision of advance-notice contracts stemming from their enforcement costs. In the present model, it is rather the fundamental inability of workers to alienate their right to quit taken in conjunction with parameters central to job separation decisions that jointly determine the mix of notice and no-notice contracts observed in equilibrium. Not all equilibrium contracts are efficient, but there is no underprovision of notice. Mandating notice cannot improve on joint value and indeed may reduce it. Furthermore, although a mandate can be merely redistributive, there are cases in which it harms all parties
Self-enforcing Union Contracts: Efficient Investment and Employment
Baldwin (1983) asks whether a firm can credibly deter union opportunism that would lead to underinvestment. We show that the punishments Baldwin considers credible exclude tougher threats that only have the appearance of being self-destructive. If the firm\u27s discount factor is sufficiently close to one, union opportunism can indeed be deterred. Moreover, we show that given the firm\u27s discount factor, a shorter lifetime of capital does not necessarily promote efficiency. Although, as Baldwin emphasizes, it does enhance the firm\u27s ability to punish union opportunism, it also creates adverse incentives for the firm to engage in opportunistic employment cuts
Combined Electroweak Analysis
Recent developments in the measurement of precision electroweak measurements
are summarised, notably new results on the mass of the top quark and mass and
width of the W boson. Predictions of the Standard Model are compared to the
experimental results which are used to constrain the input parameters of the
Standard Model, in particular the mass of the Higgs boson. The agreement
between measurements and expectations from theory is discussed.
Invited talk presented at the EPS HEP 2007 conference
Manchester, England, July 19th to 25th, 2007Comment: 7 pages and 6 figure
Earning More, Receiving Less: Loss of Benefits and Child Hunger
New research from Children's HealthWatch shows that increases in income that trigger loss of public assistance benefits can leave young children without enough food to eat. Families hat have been cut off from SNAP or TANF when their income exceeds eligibility limits are more likely to experience levels of food insecurity that require reducing the size or frequency of children's meals compared to those currently receiving benefits. Previous research has demonstrated that both SNAP and TANF reduce the likelihood of food insecurity. Income eligibility guidelines should be re-examined to ensure that a modest increase in income does not disqulaify a family from the benefits they need to keep their children healthy and well-fed. Families that successfully increase their earnings should not find themselves worse off due to a resulting loss of benefits
Children of Immigrants: Healthy Beginnings Derailed by Food Insecurity
Children of immigrants are the fastest growing child population in the United States. More than 20 percent of children under age six have immigrant parents; approximately 93 percent of these children are American citizens.Of the children who are non-citizens, two-thirds will grow up to become citizens, playing a critical role in our nation's future
Recommended from our members
Landslides on Ceres: Diversity and Geologic Context.
Landslides are among the most widespread geologic features on Ceres. Using data from Dawn's Framing Camera, landslides were previously classified based upon geomorphologic characteristics into one of three archetypal categories, Type 1(T1), Type 2 (T2), and Type 3 (T3). Due to their geologic context, variation in age, and physical characteristics, most landslides on Ceres are, however, intermediate in their morphology and physical properties between the archetypes of each landslide class. Here we describe the varied morphology of individual intermediate landslides, identify geologic controls that contribute to this variation, and provide first-order quantification of the physical properties of the continuum of Ceres's surface flows. These intermediate flows appear in varied settings and show a range of characteristics, including those found at contacts between craters, those having multiple trunks or lobes; showing characteristics of both T2 and T3 landslides; material slumping on crater rims; very small, ejecta-like flows; and those appearing inside of catenae. We suggest that while their morphologies can vary, the distribution and mechanical properties of intermediate landslides do not differ significantly from that of archetypal landslides, confirming a link between landslides and subsurface ice. We also find that most intermediate landslides are similar to Type 2 landslides and formed by shallow failure. Clusters of these features suggest ice enhancement near Juling, Kupalo and Urvara craters. Since the majority of Ceres's landslides fall in the intermediate landslide category, placing their attributes in context contributes to a better understanding of Ceres's shallow subsurface and the nature of ground ice
- …