Hierarchical architecture design and simulation environment

The Hierarchical Architectural design and Simulation Environment (HASE)is intended as a flexible tool for computer architects who wish to experiment with alternative architectural configurations and design parameters. HASE is both a design environment and a simulator. Architecture components are described by a hierarchical library of objects defined in terms of an object oriented simulation language. HASE instantiates these objects to simulate and animate the execution of a computer architecture. An event trace generated by the simulator therefore describes the interaction between architecture components, for example, fetch stages, address and data buses, sequencers, instruction buffers and register files. The objects can model physical components at different abstraction levels, eg. PMS (processor memory switch), ISP (instruction set processor) and RTL (register transfer level). HASE applies the concepts of inheritance, encapsulation and polymorphism associated with object orientation, to simplify the design and implementation of an architecture simulation that models component operations at different abstraction levels. For example, HASE can probe the performance of a processor's floating point unit, executing a multiplication operation, at a lower level of abstraction, i.e. the RTL, whilst simulating remaining architecture components at a PMS level of abstraction. By adopting this approach, HASE returns a more meaningful and relevant event trace from an architecture simulation. Furthermore, an animator visualises the simulation's event trace to clarify the collaborations and interactions between architecture components. The prototype version of HASE is based on GSS (Graphical Support System), and DEMOS (Discrete Event Modelling On Simula)

Performance Analysis of Live-Virtual-Constructive and Distributed Virtual Simulations: Defining Requirements in Terms of Temporal Consistency

This research extends the knowledge of live-virtual-constructive (LVC) and distributed virtual simulations (DVS) through a detailed analysis and characterization of their underlying computing architecture. LVCs are characterized as a set of asynchronous simulation applications each serving as both producers and consumers of shared state data. In terms of data aging characteristics, LVCs are found to be first-order linear systems. System performance is quantified via two opposing factors; the consistency of the distributed state space, and the response time or interaction quality of the autonomous simulation applications. A framework is developed that defines temporal data consistency requirements such that the objectives of the simulation are satisfied. Additionally, to develop simulations that reliably execute in real-time and accurately model hierarchical systems, two real-time design patterns are developed: a tailored version of the model-view-controller architecture pattern along with a companion Component pattern. Together they provide a basis for hierarchical simulation models, graphical displays, and network I/O in a real-time environment. For both LVCs and DVSs the relationship between consistency and interactivity is established by mapping threads created by a simulation application to factors that control both interactivity and shared state consistency throughout a distributed environment

Translating BIF into VHDL : algorithms and examples

This report describes an algorithm for automatically translating BIF system-level behavioral descriptions to behavioral VHDL. BIF is a new intermediate representation for behavioral synthesis, based on annotated state tables that supports user control of the synthesis process by allowing specification of partial design structures, unit bindings, and modification of the design at various levels of abstraction. This flexibility creates a need for behavioral verification of the design at each level of abstraction to provide feedback information to the user. Since VHDL is a well formalized, simulatable language it makes an ideal target for translation.We discuss the complexities inherent in representing BIF's hierarchical state specifications in VHDL and examine a general model for the combined representation of hierarchy, timing, concurrency, and arbitrary state transitions in VHDL.We conclude the report with several examples from a recently implemented translator

Environmental features of Chinese architectural heritage: the standardization of form in the pursuit of equilibrium with nature

We present a scientific discussion about Chinese historical architecture and cultural paradigms in order to analyze the formation of building patterns objectively connected to environmental features. In this regard, we will demonstrate the process of standardization from architectural modules related in different levels of composition around “voids”, onto cosmological urban tissues in harmony with nature. The conclusions show that we can only understand Chinese architectural patterns in relation to Dào or nature, and in turn, they possess profound social and environmental values from which we receive useful lessons to advance towards sustainability in architecture and urban planning. The authors believe that it is critical for China and the world to find a new approach to the building construction industry with an ecological and philosophical background recognizable as “Chinese” and based in its own past. In order to support the information provided in the first part of the article, the authors have conducted an environmental analysis of the traditional Chinese urban layout whose results greatly confirm the initial hypotheses, i.e. the historical fashion of constructing neighborhoods improves conditions of the town in terms of comfort and is able to save energy, thus reducing pernicious change effects

A physiological Plant Growth Simulation Engine Based on Accurate Radiant Energy Transfer

We present a new model for plant growth simulation, taking into account the eco-physiological processes driving plant development with unprecedented fidelity. The growth model, based on a physiological analysis, essentially simulates the internal function of the plant, and has been validated against measured biological data with excellent results. We show how to account for the influence of light through photosynthesis, and thereby incorporate the effects of a given plant's immediate environment on its architecture, shape and size. Since biological matter is controlled by water transpiration and received radiant enery, the model requires efficient and accurate simulation of radiant energy exchanges. We describe a complete lighting simulation system tailored for the difficult case of plants, by adapting state-of-the-art techniques such as hierarchical instanciation for radiosity and general BRDF modeling. Our results show that (a) our lighting simulation system efficiently provides the required information at the desired level of accuracy, and (b) the plant growth model is extremely well calibrated against real plants and (c) the combined system can simulate many interesting growth situations with direct feedback from the environment on the plant's characteristics. Applications range from landscape simulation to agronomical and agricultural studies, and to the design of virtual plants responding to their environment

Wayfinding in Complex Multi-storey Buildings: A vision-simulation-augmented wayfinding protocol study

Wayfinding in complex multi-storey buildings often brings newcomers and even some frequent visitors uncertainty and stress. However, there is little understanding on wayfinding in 3D structure which contains inter-storey and inter-building travelling. This paper presents the method of vision-simulation-augmented wayfinding protocol for the study of such 3D structure to find its application from investigating pedestrians’ wayfinding behaviour in general-purpose complex multi-storey buildings. Based on Passini’s studies as a starting point, an exploratory quasi-experiment was developed during the study and then conducted in a daily wayfinding context, adopting wayfinding protocol method with augmentation by the real-time vision simulation. The purpose is to identify people’s natural wayfinding strategies in natural settings, for both frequent visitors and newcomers. It is envisioned that the findings of the study can inspire potential design solutions for supporting pedestrian’s wayfinding in 3D indoor spaces. From the new method developed and new analytic framework, several findings were identified which differ from other wayfinding literature, such as (1) people seem to directly “make sense” of wayfinding settings, (2) people could translate recurring actions into unconscious operational behaviours, and (3) physical rotation and constrained views, instead of vertical travelling itself, should be problems for wayfinding process, etc. Keywords: Wayfinding Protocol; Real-time Vision Simulation; 3D Indoor Space; Activity Theory; Structure of Wayfinding process</p