New Improvements on the Echelon-Ferrers Construction
نویسندگان
چکیده
We show how to improve the echelon-Ferrers construction of random network codes introduced in [3] to attain codes of larger size for a given minimum distance.
منابع مشابه
The Expurgation-Augmentation Method for Constructing Good Plane Subspace Codes
As shown in [31], one of the five isomorphism types of optimal binary subspace codes of size 77 for packet length v = 6, constant dimension k = 3 and minimum subspace distance d = 4 can be constructed by first expurgating and then augmenting the corresponding lifted Gabidulin code in a fairly simple way. The method was refined in [36, 29] to yield an essentially computer-free construction of a ...
متن کاملMaximal Ferrers Diagram Codes: Constructions and Genericity Considerations
This paper investigates the construction of rank-metric codes with specified Ferrers diagram shapes. These codes play a role in the multilevel construction for subspace codes. A conjecture from 2009 provides an upper bound for the dimension of a rank-metric code with given specified Ferrers diagram shape and rank distance. While the conjecture in its generality is wide open, several cases have ...
متن کاملRepresentation of Subspaces and Enumerative Encoding of the Grassmannian Space
Codes in the Grassmannian space have found recently application in network coding. Representation of kdimensional subspaces of Fq has generally an essential role in solving coding problems in the Grassmannian, and in particular in encoding subspaces of the Grassmannian. Different representations of subspaces in the Grassmannian are presented. We use two of these representations for enumerative ...
متن کاملRook Poset Equivalence of Ferrers Boards
A natural construction due to K. Ding yields Schubert varieties from Ferrers boards. The poset structure of the Schubert cells in these varieties is equal to the poset of maximal rook placements on the Ferrers board under the Bruhat order. We determine when two Ferrers boards have isomorphic rook posets. Equivalently, we give an exact categorization of when two Ding Schubert varieties have iden...
متن کاملA new Bi-objective model for a Two-echelon Capacitated Vehicle Routing Problem for Perishable Products with the Environmental Factor
In multi-echelon distribution strategy freight is delivered to customers via intermediate depots. Rather than using direct shipments, this strategy is an increasingly popular one in urban logistics. This is primarily to alleviate the environmental (e.g., energy usage and congestion) and social (e.g., traffic-related air pollution, accidents and noise) consequences of logistics operations. This ...
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:
- CoRR
دوره abs/1110.2417 شماره
صفحات -
تاریخ انتشار 2010