Field Evaluation of a Modular Press-Brake-Formed Steel Tub Girder in an Application that Includes Skew and Superelevation

The Short Span Steel Bridge Alliance (SSSBA) is a group of bridge and culvert industry leaders (including steel manufacturers, fabricators, service centers, coaters, researchers, and representatives of related associations and government organizations) who have joined together to provide educational information on the design and construction of short span steel bridges in installations up to 140’-0” in length. A technical working group from within the SSSBA developed the notion for the modular shallow press-brake-formed steel tub girder as a solution for the short span steel bridge market. After extensive testing at West Virginia University and multiple successful field demonstrations, members of the SSSBA collaborated with the West Virginia Division of Highways to arrange implementation of this system. The Fourteen Mile Bridge located in Lincoln County, West Virginia, was chosen as a prime candidate to demonstrate the system due to the significant superelevation and skew present. Upon completion of the Fourteen Mile Bridge, researchers from Marshall University and West Virginia University traveled to the bridge site to perform a live load field test. This study presents the results and evaluation from experimental and analytical testing of the Fourteen Mile Bridge. Additionally, the research methods for both the experimental and analytical testing are outlined. Live load distribution factors were computed from the experimental data and analytical data, and these were compared to those computed following the AASHTO LRFD specifications. The results of this comparison reflect that the AASHTO LRFD specifications are conservative in the analysis of press-brake-formed tub girders. This report also includes an initial qualitative examination of bracing configurations for non-composite press-brake-formed tub girders. The results provide the basis for extending the work towards a closer investigation to determine the best practices of bracing

The Impact of Foot-and-Mouth Disease (FMD) on Hog, Pork, and Beef Prices: the Experience in Korea

Korea experienced two outbreaks of foot-and-mouth disease (FMD), one in the year 2000 and one in 2002. After the first outbreak, prices for hogs, pork, and beef dropped 15-20% before the government began an intervention program. The effects of these two outbreaks are examined using Box and Tiao's intervention analysis model and a GARCH model Although the second outbreak resulted in many times more animal deaths than the first outbreak, its effect on prices was much smaller. The reason may be because the government's response to the first outbreak set a precedent for the second one.Livestock Production/Industries,

Co-Clustering Network-Constrained Trajectory Data

Recently, clustering moving object trajectories kept gaining interest from both the data mining and machine learning communities. This problem, however, was studied mainly and extensively in the setting where moving objects can move freely on the euclidean space. In this paper, we study the problem of clustering trajectories of vehicles whose movement is restricted by the underlying road network. We model relations between these trajectories and road segments as a bipartite graph and we try to cluster its vertices. We demonstrate our approaches on synthetic data and show how it could be useful in inferring knowledge about the flow dynamics and the behavior of the drivers using the road network

A new class of dendrimeric gecko legs polymer particles with extraordinary structure- building, gelation and adhesive capabilities

Particulate rheology modifiers are important component of many cosmetics, food, and pharmaceutical formulations. The efficiency of rheology modifiers is usually determined by the interplay between surface area and shape of suspended particles. We will present a new class of nanofibrilated dendrimeric polymer particles (DPPs) with very high surface area and morphology engineered for applications in rheology modifiers and adhesives. The DPPs are fabricated in a novel efficient and scalable process for liquid-based synthesis of nanomaterials by antisolvent precipitation in turbulently sheared medium. The process allows for a variety of polymers to be readily made into DPPs which are hierarchically structured, with a big branched corona of nanofibers spreading out in all directions. The hierarchical structure endows DPPs with high excluded volume. They build a stable three-dimensional network leading to gel-like behavior at fractions as low as 1-2 vol.% of DPPs in various liquids. In addition, the biomimetic similarity of their structure to the gecko lizards’ setae endows the DPPs with excellent adhesion and cohesion properties. Our results demonstrate that this strong adhesion and cohesion are attributed to the contact splitting and van der Waals interactions of their nanofibrous structures. This new class of polymeric particles opens new ways to make strong non-covalent binding coatings, new types of dry adhesives, nonwovens and fluid-gels. They could have a transformative role as rheology modifiers and nano-adhesives to hair and skin in many cosmetics formulations. Please click Additional Files below to see the full abstract

Transparent and soft elastomeric composites and oil/water biphasic systems with stimuli-triggered release of “invisible” liquid

The synthesis, principles, and properties of a new class of stimuli-responsive soft matter biphasic composites will be introduced. The soft composite consists of more than 30% of aqueous solution emulsion (of micron-sized droplets) optically hidden in a matrix of silicone or hydrocarbon gel. Through delicate adjustment of the refractive index (RI) of the internal aqueous phase, the composite is completely transparent to visible light and the internally dispersed aqueous droplet phase is invisible to the naked eye. Multiple phases can be included in the form of gelled multiple emulsion. The composite exhibits unique stimuli-response capabilities, such as changing its optical transmittance upon mechanical, thermal, osmotic and other stresses. Intrusion damage causes the composite to release the RI matched aqueous phase, which causes change in transparency of color. In addition, when the composite is present in an aqueous medium where salinity is different from the dispersed phase, the osmotic pressure in the droplets causes instantaneous transparency change triggered by osmotic pressure. This enables us to measure osmotic pressure of the aqueous medium quickly. The new composites and gels could find many applications including a number of cosmetics and other consumer products with attractive and unusual appearance and stimulus-triggered active ingredients delivery. Please click Additional Files below to see the full abstract

The utility of PSMA and PSA immunohistochemistry in the cytologic diagnosis of metastatic prostate carcinoma

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/107502/1/dc23075.pd

Properties of the symplectic structure of General Relativity for spatially bounded spacetime regions

We continue a previous analysis of the covariant Hamiltonian symplectic structure of General Relativity for spatially bounded regions of spacetime. To allow for near complete generality, the Hamiltonian is formulated using any fixed hypersurface, with a boundary given by a closed spacelike 2-surface. A main result is that we obtain Hamiltonians associated to Dirichlet and Neumann boundary conditions on the gravitational field coupled to matter sources, in particular a Klein-Gordon field, an electromagnetic field, and a set of Yang-Mills-Higgs fields. The Hamiltonians are given by a covariant form of the Arnowitt-Deser-Misner Hamiltonian modified by a surface integral term that depends on the particular boundary conditions. The general form of this surface integral involves an underlying ``energy-momentum'' vector in the spacetime tangent space at the spatial boundary 2-surface. We give examples of the resulting Dirichlet and Neumann vectors for topologically spherical 2-surfaces in Minkowski spacetime, spherically symmetric spacetimes, and stationary axisymmetric spacetimes. Moreover, we show the relation between these vectors and the ADM energy-momentum vector for a 2-surface taken in a limit to be spatial infinity in asymptotically flat spacetimes. We also discuss the geometrical properties of the Dirichlet and Neumann vectors and obtain several striking results relating these vectors to the mean curvature and normal curvature connection of the 2-surface. Most significantly, the part of the Dirichlet vector normal to the 2-surface depends only the spacetime metric at this surface and thereby defines a geometrical normal vector field on the 2-surface. Properties and examples of this normal vector are discussed.Comment: 46 pages; minor errata corrected in Eqs. (3.15), (3.24), (4.37) and in discussion of examples in sections IV B,