Value of time

This paper presents a modified k-nearest neighbor approach for streamflow generation. In this model, first, a local polynomial (a nonparametricfunction) is fitted to estimate the mean of the conditional probability density function. The simulation at any time point ‘t+1’ given the value at the current time ‘t’ then involves two steps (i) obtaining the conditional mean from the local

ABSTRACT: The economic model of the household has been used extensively to ex-amine questions relating to work within the household. This essay takes a critical look at this model and these household work applications. It concludes that the model provides several ...

This paper presents the results of a study which examined the premise that NASA's Small Aircraft Transportation System (SATS) concept will be seen as an economical alternative to automobiles, when considering the economic value of a traveler's time. Grounded in previous research into SATS Life Cycle Costs, Travel$ense software was used to examine three levels of cost of a hypothetical

The propagation of plane waves in a fiber-reinforced, anisotropic thermoelastic half-space proposed by Lord-Shulman under the effect of a magnetic field is discussed. The problem has been solved numerically using a finite element method. Numerical results for the temperature distribution, the displacement components, and the thermal stress are given and illustrated graphically. Comparisons are made with the results predicted by the theory of generalized thermoelasticity with one relaxation time for different values of time. It is found that the reinforcement has a great effect on the distribution of field quantities.

In this study, Swedish stated preference data is used to derive estimated values of commuting time (VOCT). Both spouses in two-earner households are individually making trade-offs between commuting time and wage; both with regard to their own commuting time and wage only, as well as when both their own commuting time and wage and their spouse's commuting time and wage

A discussion of an article with the aforementioned title, published in this issue of this journal, is presented. The aim of the author of this comment is to raise some issues as a contribution to the debate on the economic success of the London congestion charge. The author questions the worth of time savings as calculated by Prud'homme and Bocajero.

We present a perturbative construction of interacting quantum field theories on smooth globally hyperbolic (curved) space-times. We develop a purely local version of the Stückelberg–Bogoliubov–Epstein–Glaser method of renormalization by using techniques from microlocal analysis. Relying on recent results of Radzikowski, Köhler and the authors about a formulation of a local spectrum condition in terms of wave front sets of correlation functions of quantum fields on curved space-times, we construct time-ordered operator-valued products of Wick polynomials of free fields. They serve as building blocks for a local (perturbative) definition of interacting fields. Renormalization in this framework amounts to extensions of expectation values of time-ordered products to all points of space-time. The extensions are classified according to a microlocal generalization of Steinmann scaling degree corresponding to the degree of divergence in other renormalization schemes. As a result, we prove t...

We obtain confidence intervals for willingness-to-pay (WTP) measures derived from a mode choice model estimated to analyse travel demand for suburban trips in the two main interurban corridors in Gran Canaria island, using a mixed RP/SP data base. We considered a specification of the systematic utility that incorporates income effect and interactions among socioeconomic variables and level-of-service attributes, as well

Route choice models are widely used for the prediction of passengers and cargo movements by planners. This paper presents the application of a methodology, introduced initially for the prediction of route choice of bicycles, now adapted to motorcycles and trucks. The adaptation of the methodology allowed the improvement of the original analysis algorithm increasing the number of considered network attributes

Rapid Single Flux Quantum (RSFQ) logic is well-known for its ultra-high switching speed and extremely low power consumption. In this paper, we present two original experiments to demonstrate that it's also a reliable technology and its reliability is sufficient even for such a large-scale system as a proposed petaflops-scale HTMT computer. We have measured the bit error rate (BER) for a circular register of inverters representing a critical path of a 64-bit integer adder, and timing jitter in a 200 Josephson junction (JJ) long transmission line, imitating a branch of a clock distribution tree, both being important and representative building blocks of the HTMT computer. For the adder critical path we have demonstrated the highest clock frequency of 17 GHz, latency of 860 ps and BER of 10-19 for 3.5 μm technology of HYPRES, Inc. The value of timing jitter was 200 fs per JJ for 1.5 μm technology of TRW, Inc. These figures are in good agreement with our simulations

We propose a statistical approach for minimizing on-chip communication bus width and number of buses with reduced communication energy under timing yield constraint. The slack is exploited to maximize sharing of buses and to reduce energy by simultaneously scaling the voltage during the communication synthesis. Because of the diversity of applications to be run on a single SoC, there exists variability of data size to be transferred among the on-chip communicating modules. This variability of data size is modeled as a normally distributed random variable. The resulting synthesis problem is relaxed to the convex quadratic optimization problem and is solved efficiently using a convex optimization tool. The effectiveness of our approach is demonstrated by applying optimization to an automatically generated benchmark and a real-life application. By varying the value of timing yield constraint, a trade-off between minimization of buses and energy reduction is explored. The experimental results show the significant reduction of communication energy with the increasing timing yield. However, the timing yield offers a limitation to minimize the size of bus width and number of buses, if the yield is increased beyond a certain limit