Mathematical programming accelerates implementation of agro-industrial sugarcane complex

With the current demand for Brazilian sugarcane, the importance to investors of a faster implementation of agro-industrial complexes has been increasing. Estimates suggest that a 4-year implementation may enhance financial value creation by 10% when compared to the usual 6-year implementation. Given a desired production and a target implementation horizon, the quadratic programming model presented in this paper offers a feasible plantation schedule with minimum deviation from the plan. The model was used as an important tool in two business plans.     

Valuations on lattice polytopes

Let L be a lattice (that is, a Z-module of finite rank), and let L=P(L) denote the family of convex polytopes with vertices in L; here, convexity refers to the underlying rational vector space V=Q⊗L. In this paper it is shown that any valuation on L satisfies the inclusion-exclusion principle, in the strong sense that appropriate extension properties of the valuation hold. Indeed, the core result is that the class of a lattice polytope in the abstract group L=P(L) for valuations on L can be identified with its characteristic function in V. In fact, the same arguments are shown to apply to P(M), when M is a module of finite rank over an ordered ring, and more generally to appropriate families of (not necessarily bounded) polyhedra.     

On valuing and hedging European options when volatility is estimated directly

We quantify the effects on contingent claim valuation of using an estimator for the unknown volatility σ of a geometric Brownian motion (GBM) process. The theme of the paper is to show what difficulties can arise when failing to account for estimation risk. Our narrative uses a direct estimator of volatility based on the sample standard deviation of increments of the underlying Brownian motion. After replacing the direct estimator into the GBM, we derive the resulting distribution function of the approximated GBM for any time point. This allows us to present post-estimation distributions and valuation formulae for an assortment of European contingent claims that are in accord with many of the basic properties of the underlying risk-neutral process, and yet better reflect the additional uncertainties and risks that exist in the Black-Scholes-Merton paradigm.     

R0代数的正则性及其Fuzzy拓扑表现定理

以ΩM记R0代数M到单位区间的全体赋值之集。本文先讨论R0代数的正则性问题,得到了关于R0代数正则性的一些结论。从而可通过一种自然的方法在ΩM上引入Fuzzy拓扑,建立了R0代数的Fuzzy拓扑表现定理。     

Ramification of valuations

In this paper we develop a very explicit theory of ramification of general valuations in algebraic function fields. In characteristic zero and arbitrary dimension, we obtain the strongest possible generalization of the classical ramification theory of local Dedekind domains. We further develop a ramification theory of algebraic functions fields of dimension two in positive characteristic. We prove that local monomialization and simultaneous resolution hold under very mild assumptions, and give pathological examples.     

Lorenzen Monoids: A Multiplicative Approach to Kronecker Function Rings

Using the formalism of module systems on a commutative cancellative monoid, we generalize the classical concept of Lorenzen monoids to obtain a multiplicative model for the semistar Kronecker function ring introduced by Fontana and Loper. We prove a universal mapping property and investigate the generalized Lorenzen monoid from a valuation-theoretic and an ideal-theoretic point of view.     

Prime T-Ideals in Polynomial and Power Series Rings Over a Pseudo-Valuation Domain

Let R be an m-dimensional pseudo-valuation domain with residue field k, let V be the associated valuation domain with residue field K, and let k ₀ be the maximal separable extension of k in K. We compute the t-dimension of polynomial and power series rings over R. It is easy to see that t-dim R[x ₁,…, x _n ] = 2 if m = 1 and K is transcendental over k, but equals m otherwise, and that t-dim R[[x ₁,…, x _n ]] = ∞ if R is a nonSFT-ring. When R is an SFT-ring, we also show that: (1) t-dim R[[x]] = m; (2) t-dim R[[x ₁,…, x _n ]] = 2m ? 1, if n ≥ 2, K has finite exponent over k ₀, and [k ₀: k] < ∞; (3) t-dim R[[x ₁,…, x _n ]] = 2m, otherwise.     

On Extensions of Semilocal Prüfer Domains

One of the most important results of Chevalley's extension theorem states that every valuation domain has at least one extension to every extension field of its quotient field. We state a generalization of this result for Prüfer domains with any finite number of maximal ideals. Then we investigate extensions of semilocal Prüfer domains in algebraic field extensions. In particular, we find an upper bound for the cardinality of extensions of a semilocal Prüfer domain. Moreover, we show that any two extensions of a semilocal Prüfer domain are incomparable (by inclusion) in an algebraic extension of fields.     

智力资本度量方法的比较与评价

本文论述了智力资本的定义及构成 ,分析了度量智力资本的基本方法及其他方法 ,并对各种度量方法的特点、适用范围进行了比较与评价