Auto-Generation of Pipelined Hardware Designs for Polar Encoder

This paper presents a general framework for auto-generation of pipelined polar encoder architectures. The proposed framework could be well represented by a general formula. Given arbitrary code length $N$ and the level of parallelism $M$, the formula could specify the corresponding hardware architecture. We have written a compiler which could read the formula and then automatically generate its register-transfer level (RTL) description suitable for FPGA or ASIC implementation. With this hardware generation system, one could explore the design space and make a trade-off between cost and performance. Our experimental results have demonstrated the efficiency of this auto-generator for polar encoder architectures

Evaluating Projects in a Dynamic Economy: Some New Envelope Results

This paper is concerned with the modern theory of social cost-bene.t analysis in a dynamic economy. The theory emphasizes the role of a comprehensive, forward- looking, dynamic welfare index within the period of the project rather than that of a project.s long-term consequences. However, what constitutes such a welfare index remains controversial in the recent literature. In this paper, we attempt to shed light on the issue by deriving three equivalent cost-bene.t rules for evaluating a small project. In particular, we show that the direct change in net national product (NNP) quali.es as a convenient welfare index without involving any other induced side e¤ects. The project evaluation criterion thus becomes the present discounted value of the direct changes in NNP over the project period. We also illustrate the application of this theory in a few stylized examples.dynamic cost-bene.t analysis; net national product; project evaluation; welfare index

On the Choice of Metrics in Dynamic Welfare Analysis: Utility versus Money Measures

This paper is concerned with the choice of metrics for social cost-benefit analysis and dynamic welfare comparisons. In a utility-theoretic framework, we show that there is always a money measure that can serve as a substitute for the maximized utility wealth. Thus, under the non-arbitrage course of discount rate, the choice between utility and money measures has no real effect on project evaluations. We also define a generalized comprehensive net national product measure with a consumer surplus term incorporated, which is completely consistent with the Weitzman foundation. It is shown that while a green (comprehensive) NNP growth simply reflects the income effect, the change in consumer surplus captures the welfare effect of relative price changes. We argue that the reason for green NNP to be a weak welfare indicator is not due to its choice of money metric per se but the ignorance of a consumer surplus term.Dynamic cost-benefit analysis; green national accounting; utility versus money metrics; Weitzman´s theorem

Genuine Saving under Stochastic Growth

The concept of genuine saving appeared for the first time in a proof of a now well known theorem in Weitzman (1976). It was reinvented and used as a local welfare indicator by Pearce and Atkinson (1993). The purpose of this paper is to generalize this welfare measure to a stochastic Brownian motion context. We will use a stochastic version of a growth model introduced by Ramsey (1928). The particular model was developed by Merton (1975). Although the model is simple, it is enough to understand what its welfare results will look like in a general case.Welfare measures under growth and uncertainty; diversified risk versus undiversified risk

The Role of the Hamiltonian in Dynamic Price Index Theory

This paper is an attempt to investigate the cost-of-living index problem in a general equilibrium multi-sector growth model. Instead of using the utility function as a compensation criterion as Konüs’ (1924) did in his original contribution, we take advantage of the current-value Hamiltonian in constructing our dynamic price index. Since the Hamiltonian is a constancy-equivalent of future utilities (Weitzman, 1976), the dynamic price index is defined in terms of the minimum expenditure that, under alternative prices, would support the constancy-equivalent-utility level in the future. We show that, when properly deflated by the dynamic price index, the real comprehensive net national product becomes an ideal measure for dynamic welfare comparisons. For some special cases, we show that the dynamic price index reduces to the simple static index.Dynamic index theory; Hamiltonian; ideal deflator

Money Metrics Welfare Measures in Imperfect Markets under Growth

This paper shows how utility based welfare measures in dynamic general equilibrium under imperfect markets can be transferred into a money metrics. In order to do this, we need to price forward looking components measured in units of utility. The typical comprehensive quasi-static welfare measure contains a core that looks like a comprehensive (green) NNP component, as well as additional consumer surplus terms for both consumption goods and the externality. In addition, it contains a forward looking component with the discounted value of the marginal externality as the function to be integrated over time is also required. To accomplish this, we need a price index that is independent of the market basket, or to assume that the marginal utility of income is constant over time. With respect to local welfare measures it turn out that growth in traditional NNP will surprisingly work, provided that we condition on a positive average marginal rate of return of investment, and use an augmented genuine saving concept.Welfare measurement under growth; imperfect markets; utility versus money metrics

Expected high energy emission from GRB 080319B and origins of the GeV emission of GRBs 080514B, 080916C and 081024B

We calculate the high energy (sub-GeV to TeV) prompt and afterglow emission of GRB 080319B that was distinguished by a naked-eye optical flash and by an unusual strong early X-ray afterglow. There are three possible sources for high energy emission: the prompt optical and $\gamma$-ray photons IC scattered by the accelerated electrons, the prompt photons IC scattered by the early external reverse-forward shock electrons, and the higher band of the synchrotron and the synchrotron self-Compton emission of the external shock. There should have been in total {hundreds} high energy photons detectable for the Large Area Telescope (LAT) onboard the Fermi satellite, and {tens} photons of those with energy $> 10$ GeV. The $> 10$ GeV emission had a duration about twice that of the soft $\gamma$-rays. AGILE could have observed these energetic signals if it was not occulted by the Earth at that moment. The physical origins of the high energy emission detected in GRB 080514B, GRB 080916C and GRB 081024B are also discussed. These observations seem to be consistent with the current high energy emission models.Comment: Accepted for publication in MNRAS, the interpretation of GRB 080916C has been extended, main conclusions are unchange