Distribution of Value of Time and Ways to Model Value of Time in Long-Range Planning Models

As managed lanes (ML) become more integrated in regional urban networks with existing general purpose (GP) lanes, the distribution of travelers’ value of time (VOT) is becoming more important for transportation planning agencies to quantify in order to accurately predict future travel patterns. Since travelers’ VOT varies depending on a multitude of factors, this study investigates ways that we can determine the VOT distribution of a region from existing travel data as well as effective ways that we can model VOT using traffic assignment algorithms. In networks with available link volumes and toll data on segments where travelers have the option of choosing to stay on the GP lanes or entering a ML facility, a VOT distribution can be inferred assuming that travelers who enter the ML choose to do so based on a certain “threshold” VOT. When modeling these VOT distributions, errors are observed in the traffic assignment results when both the continuous nature of VOT distributions are discretized, and when varying toll values are assumed to be constant. Specifically in the context of TransCAD software, link travel time errors appear to be much less significant than flow errors when tested on a nine node network. Additional experimentation on larger regional networks is needed to verify the significance of these errors and their impact on predicted travel patterns.Civil, Architectural, and Environmental Engineerin

Reef Habitats in the Middle Atlantic Bight: Abundance, Distribution, Associated Biological Communities, and Fishery Resource Use

One particular habitat type in the Middle Atlantic Bight is not well recognized among fishery scientists and managers, although it is will known and used by recreational and commercial fisheries. This habitat consists of a variety of hard-surface, elevated relief "reef" or reef-like environments that are widely distributed across the predominantly flat or undulating, sandy areas of the Bight and include both natural rocky areas and man-made structures, e.g. shipwrecks and artificial reefs. Although there are natural rock and shellfish reefs in southern New England coastal waters and estuaries throughout the Bight, most reef habitats in the region appear to be man-made reef habitat modification/creation may be increasing. Very little effort has been devoted to the study of this habitat's distribution, abundance, use by living marine resources and associated biological communities (except on estuarine oyster reefs) and fishery value or management. This poorly studied and surveyed habitat can provide fish refuge from trawls and can be a factor in studies of the distribution and abundance of a variety of reef-associated fishery resources. This review provides a preliminary summary of information found on relative distribution and abundance of reef habitat in the Bight, the living marine resources and biological communities that commonly use it, threats to this habitat and its biological resources, and the value or potential value of artificial reefs to fishery or habitat and its biological resources, and the value or potential value of artificial reefs to fishery or habitat managers. The purpose of the review is to initiate an awareness among resource managers about this habitat, its role in resource management, and the need for research

Introduction to Library Trends 55 (3) Winter 2007: Libraries in Times of War, Revolution and Social Change

published or submitted for publicatio

Simulation of main plasma parameters of a cylindrical asymmetric capacitively coupled plasma micro-thruster using computational fluid dynamics

Computational fluid dynamics (CFD) simulations of a radio-frequency (13.56 MHz) electrothermal capacitively coupled plasma (CCP) micro-thruster have been performed using the commercial CFD-ACE+ package. Standard operating conditions of a 10W, 1.5 Torr argon discharge were used to compare with previously obtained experimental results for validation. Results show that the driving force behind plasma production within the thruster is ion-induced secondary electrons ejected from the surface of the discharge tube, accelerated through the sheath to electron temperatures up to 33.5 eV. The secondary electron coefficient was varied to determine the effect on the discharge, with results showing that full breakdown of the discharge did not occur for coefficients less than or equal to 0.01

The effect of surface heterogeneity on cloud absorption estimates

This study presents a systematic and quantitative analysis of the effect of inhomogeneous surface albedo on shortwave cloud absorption estimates. We used 3D radiative transfer modeling over a checkerboard surface albedo to calculate cloud absorption. We have found that accounting for surface heterogeneity enhances cloud absorption. However, the enhancement is not sufficient to explain the reported difference between measured and modeled cloud absorption

Intergovernmental fiscal relations in China

The choice of the"right"fiscal relationship between central, provincial, and local governments depends on how a government weighs the benefits of decentralized economic development policies against the costs of having less effective central fiscal management. Three strong forces justify more fiscal centralization in China's highly decentralized fiscal system. First, Bouts of inflation and recurrent fiscal deficits can be seen as calling for more central control over the budget. Second, Reform of an economic system relies heavily on the use of tax policy as an allocative instrument to influence economic decisions. Local control of the implementation of the tax system can and probably has compromised some objectives of the central government's tax policy. Gaining tighter control over the revenue system will probably require reducing if not eliminating local government discretion in providing special tax concessions. Third, if the center wants to move ahead with price reform and to encourage enterprise reform, it needs a more centrally controlled revenue sharing or assignment system that reduces the dislocating effects of such reforms. Bahl and Wallich conclude that a reformed system of intergovernmental finance must meet the center's needs for stabilization and the provinces'needs for revenue and equalized spending capacity, supplemented by an improved system of financing local capital expenditures through borrowing, a system of benefit charges and improved planning.Public Sector Economics&Finance,National Governance,Banks&Banking Reform,Municipal Financial Management,Urban Economics

EQUAL PAY – THE TIME-BOMB UNDER PAY STRUCTURES IN ROMANIA

One of the major consequences of Romania joining the European Union is its obligation to implement European Directives with regard to employment protection. One aspect of that is likely to have major social and cost implications is the legislation regarding equal pay for men and women. The dimension of equal pay for work that is the same or broadly similar is relatively straightforward. The more complicated and more far reaching requirement is for equal pay for men and women for work of equal value. In determining whether jobs are of equal value regard has to had in particular to effort, skill and decision making. Comparisons are valid with other jobs in the same organisation but not between organisations. In addition comparisons are only legally valid if they are on the basis that a person of the opposite sex is being paid more for work of equivalent value. Such comparisons are subjective and often very complicated. Job evaluation schemes can help in creating a framework for comparison but being inherently subjective are open to challenge. The situation is further complicated by the fact that comparisons can also be made on any one element of the remuneration package. Experience in the U.K. and other member EU countries is that equal pay claims are very much on the rise, can take years to resolve and can be hugely expensive. Although legal costs can be significant the main costs are in settling group claims and the ‘knock-on’ effect on the rest of an organisation’s pay structure. Whilst it may take time for this development to gather pace in Romania now is the time for organisations to review their pay structures and take preventative action to try and reduce the conflict that will inevitably occur.employment protection, equal pay, equal pay for work of equal value, pay structures

Asymptotically Stable Walking of a Five-Link Underactuated 3D Bipedal Robot

This paper presents three feedback controllers that achieve an asymptotically stable, periodic, and fast walking gait for a 3D (spatial) bipedal robot consisting of a torso, two legs, and passive (unactuated) point feet. The contact between the robot and the walking surface is assumed to inhibit yaw rotation. The studied robot has 8 DOF in the single support phase and 6 actuators. The interest of studying robots with point feet is that the robot's natural dynamics must be explicitly taken into account to achieve balance while walking. We use an extension of the method of virtual constraints and hybrid zero dynamics, in order to simultaneously compute a periodic orbit and an autonomous feedback controller that realizes the orbit. This method allows the computations to be carried out on a 2-DOF subsystem of the 8-DOF robot model. The stability of the walking gait under closed-loop control is evaluated with the linearization of the restricted Poincar\'e map of the hybrid zero dynamics. Three strategies are explored. The first strategy consists of imposing a stability condition during the search of a periodic gait by optimization. The second strategy uses an event-based controller. In the third approach, the effect of output selection is discussed and a pertinent choice of outputs is proposed, leading to stabilization without the use of a supplemental event-based controller

Validation of a pair of computer codes for estimation and optimization of subsonic aerodynamic performance of simple hinged-flap systems for thin swept wings

Extensive correlations of computer code results with experimental data are employed to illustrate the use of linearized theory attached flow methods for the estimation and optimization of the aerodynamic performance of simple hinged flap systems. Use of attached flow methods is based on the premise that high levels of aerodynamic efficiency require a flow that is as nearly attached as circumstances permit. A variety of swept wing configurations are considered ranging from fighters to supersonic transports, all with leading- and trailing-edge flaps for enhancement of subsonic aerodynamic efficiency. The results indicate that linearized theory attached flow computer code methods provide a rational basis for the estimation and optimization of flap system aerodynamic performance at subsonic speeds. The analysis also indicates that vortex flap design is not an opposing approach but is closely related to attached flow design concepts. The successful vortex flap design actually suppresses the formation of detached vortices to produce a small vortex which is restricted almost entirely to the leading edge flap itself