Tacit definition
Permission to copy without fee all or part of this material is granted provided that the copies are not made or distributed for direct commercial advantage, the ACM copyright notice and the title of the publication and its date appear, and notice is given that copying is by permission of the Association for Computing Machinery. To copy otherwise, or to republish, requires a fee and/or specific permission. ~ 1991 ACM 0-89791 -441-4/91 /0008/0202 ...$1 .50
The role of APL and J in high-performance computation
Although multicomputers are becoming feasible for solving large problems, they are difficult to program: Extraction of parallelism from scalar languages is possible, but limited. Parallelism in algorithm design is difficult for those who think in von Neumann terms. Portability of programs and programming skills can only be achieved by hiding the underlying machine architecture from the user, yet this may impact performance on a specific host.APL, J, and other applicative array languages with adequately rich semantics can do much to solve these problems. The paper discusses the value of abstraction and semantic richness, performance issues, portability, potential degree of parallelism, data distribution, process creation, communication and synchronization, frequency of program faults, and clarity of expression. The BLAS are used as a basis for comparison with traditional supercomputing languages.
On the use of the Hardening Soil Small Strain model in geotechnical practice
This article highlights the importance of using advanced constitutive soil models in numerical modelling as daily geotechnical practice. In this context, the Hardening Soil (HS) model is presented as the most advanced soil model implemented in the ZSoil finite element code. The article recalls the basic features of the HS model and it explains their role in numerical simulations. The role of pre-failure non-linear behaviour of soils is also discussed. An application of the HS model is illustrated on typical geotechnical problems such as retaining wall excavation, tunnel excavation and undrained loading followed by consolidation.