The system of model building codes and voluntary product standards used in the United States for structural lumber and engineered wood products can appear complicated and confusing to those introduced to it for the first time. This paper discusses the various types of structural wood products commonly used in U.S. residential and commercial construction, and the system of building codes and pro...

In general, encoding for LDPC codes can be difficult to realize efficiently. This paper presents techniques and architectures for LDPC encoding that are efficient and practical for a particular class of codes. These codes are the irregular partitioned permutation LDPC codes recently introduced by the author at ICC’03, [4]. Since these codes are quasi-cyclic, it is known that a simpler encoding ...

Unit memory convolutional codes with generator matrices, which are composed of circulant suhmatrices, are introduced. This structure facilitates the analysis as well as an efficient search for good codes. Equivalences among such codes and consider some of the basic structural properties are discussed. In particular, catastrophic encoders and minimal encoders are characterized and dual codes tre...

This paper is concerned with construction and structural analysis of both cyclic and quasi-cyclic codes, particularly LDPC codes. It consists of three parts. The first part shows that a cyclic code given by a parity-check matrix in circulant form can be decomposed into descendant cyclic and quasi-cyclic codes of various lengths and rates. Some fundamental structural properties of these descenda...

Convolutional codes over rings are particularly suitable for representing codes over phase modulation signals. In order to develop a complete structural analysis of this class of codes, it is necessary to study rational matrices over rings, which constitutes the generator matrices (encoders) for such convolutional codes. Noncatastrophic, minimal, systematic and basic generator matrices are intr...

NASA is developing a "tool box" that includes a number of advanced structural analysis computer codes which, taken together, represent the comprehensive fracture mechanics capability required to predict the onset of widespread fatigue damage. These structural analysis tools have complementary and specialized capabilities ranging from a finite-element-based stress-analysis code for twoand three-...

Simulations of fluid-structure interaction (FSI) are increasingly being used to calculate the mutual interaction between a fluid flow and a flexible structure. Mature, reliable and optimized codes are readily available to solve flow equations or structural equations separately but the handful of monolithic codes which are able to solve all equations in an FSI problem simultaneously have not yet...

The article is intended for the study of issue systematization laws in field defense through its codification. It was found that codification recognized as highest level and most perfect type laws, a result which large number separate legal acts are replaced by one single, consolidated, updated codified act.
 relevance problem substantiated presence state task defined Decree President Ukra...