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A new odd-symmetric filter for ISI suppression and VSB transmission is proposed. The frequency response of the proposed filter is similar to that of an ideal raised-cosine filter, but in contrast to raised-cosine the new filter is realizable, e.g. using simple active filters. Simulation results show that concerning ISI suppression the new filter is significantly more efficient than the classical Butterworth or Chebyshev filters. The proposed filter can be also used as a VSB filter for TV modulators and demodulators. Index Terms--Intersymbol interference-ISI, odd-symmetric filter, raised-cosine filter, VSB filter.

The one-dimensional viscous conservation law is considered on the whole line \displaystyle u_t + f(u)_x=\varepsilon u_{xx},\quad (x,t)\in \mathbb{R}\times \overline {\mathbb{R}_{+}},\quad \varepsilon >0, subject to positive measure initial data. The flux f\in C^1(\mathbb{R}) is assumed to satisfy a p-condition, a weak form of convexity. In particular, any flux of the form f(u)=\sum _{i=1}^Ja_iu^{m_i} is admissible if a_i>0,\,m_i>1,\,\,i=1,2,\ldots,J. The only case treated hitherto in the literature is f(u)=u^m [Arch. Rat. Mech. Anal. 124 (1993), pp. 43-65] and the initial data is a ''single source'', namely, a multiple of the delta function. The corresponding solutions have been labeled as ''source-type'' and the treatment made substantial use of the special form of both the flux and the initial data. In this paper existence and uniqueness of solutions is established. The method of proof relies on sharp decay estimates for the viscous Hamilton-Jacobi equation. Some estimates are independent of the viscosity coefficient, thus leading to new estimates for the (inviscid) hyperbolic conservation law. [ABSTRACT FROM AUTHOR]

The initial-boundary value problem for the (viscous) nonlinear scalar conservation law is considered, \[ \begin{array}{ccc} u^\varepsilon_t +f(u^\varepsilon)_x=\varepsilon u^\varepsilon_{xx},\quad x\in\mathbb{R}_+= (0,\infty), \quad 0\leq t\leq T, \quad \varepsilon>0,\\ u^\varepsilon(x,0)=u_0(x),\\ u^\varepsilon(0,t)=g(t).\\ \end{array} \] The flux f(ξ) ∈ C2(ℝ) is assumed to be convex (but not strictly convex, i.e. f″(ξ)≥ 0). It is shown that a unique limit u = lim∊ → 0 u∊ exists. The classical duality method is used to prove uniqueness. To this end parabolic estimates for both the direct and dual solutions are obtained. In particular, no use is made of the Kružkov entropy considerations. [ABSTRACT FROM AUTHOR]

Despite the current emphasis in transfusion medicine on regulatory compliance and cost containment, there is continuing activity in quality improvement of blood products. Quality can be assessed by measuring both benefit and risk. High quality products are those in which the benefit is maximized and the risk minimized. Risk, in the context of platelet transfusions, is minimized by reducing infectious agents, sources of allergic reactions, and other factors likely to cause adverse reactions in recipients. Benefit can be better described as potency. Potency is the ability to produce a desired effect. For platelet concentrates, potency has both quantitative [platelet yield] and qualitative [platelet viability, survival, and function] components. There are many activities which may influence the potency of the final transfused platelet product and these are summarized in Figure 1. It is helpful to review each step in order to assess the potential impact on the potency of the final transfused product.