Towards a proof of the decidability of the momentary stagnation of the growth function of D0L systems
نویسندگان
چکیده
This paper proves the decidability of several problems in the theory of HD0L, D0L and PD0L systems, some of which that have been proved before but are now proved in a different way. First, the paper tackles the decidability of the nilpotency of HD0L systems and the infinitude of PD0L languages. Then, we prove the decidability of the problem of momentary stagnation of the growth function of PD0L systems. Finally, we suggest a way to solve the decidability of the momentary stagnation of the growth function ofD0L systems, proving the decidability of the infinitude ofHD0L as a trivial consequence. © 2005 Elsevier B.V. All rights reserved.
منابع مشابه
Stagnation-point flow of a viscous fluid towards a stretching surface with variable thickness and thermal radiation
In the present analysis, we study the boundary layer flow of an incompressible viscous fluid near the two-dimensional stagnation-point flow over a stretching surface. The effects of variable thickness and radiation are also taken into account and assumed that the sheet is non-flat. Using suitable transformations, the governing partial differential equations are first converted to ordin...
متن کاملAixsymmetric Stagnation Point Flow of a Viscous Fluid on a Moving Cylinder with Time Dependent Axial Velocity
The unsteady viscous flow in the vicinity of an axisymmetric stagnation point of an infinite moving cylinder with time-dependent axial velocity is investigated. The impinging free stream is steady with a strain rate k. An exact solution of the Navier-Stokes equations is derived in this problem. A reduction of these equations is obtained by use of appropriate transformations. The general self-si...
متن کاملEffect of charge on separation of liposomes upon stagnation
Abstract Liposomes are used widely as drug delivery systems in different forms including nanosuspensions, osmotic pumps, infusion pumps and IV injections. Some of these systems (e.g. infusion or osmotic pumps) might stay stagnant for a long time during or before administration, and therefore, might face phase separation. In spite of these, there is no data available about the behavior of lipos...
متن کاملA new proof for the decidability of D0L ultimate periodicity
L systems were originally introduced by A. Lindenmayer to model the development of simple filamentous organisms [6, 7]. The challenging and fruitful study of these systems in the 70s and 80s created many new results and notions [9]. In this paper we consider the important problem of recognizing ultimately periodic D0L sequences. Let A be a finite alphabet and denote the empty word by ε . A D0L ...
متن کاملEffect of bilayer flexibility and medium viscosity on separation of liposomes upon stagnation
Liposomes are widely used as drug delivery systems in different forms including osmotic pumps, infusion and IV injection. In spite of these, there is no data available about their behavior under convective flow (e.g. infusion or osmotic pumps) and upon stagnation in such drug delivery systems. As a part of a series of investigations in this area, the present study investigates the effects of vi...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید
ثبت ناماگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید
ورودعنوان ژورنال:
- Theor. Comput. Sci.
دوره 341 شماره
صفحات -
تاریخ انتشار 2005