Charles S. Han

A multi-agent based framework for the simulation of human and social behaviors during emergency evacuations

Many computational tools for the simulation and design of emergency evacuation and egress are now available. However, due to the scarcity of human and social behavioral data, these computational tools rely on assumptions that have been found inconsistent or unrealistic. This paper presents a multi-agent based framework for simulating human and social behavior during emergency evacuation. A prototype system has been developed, which is able to demonstrate some emergent behaviors, such as competitive, queuing, and herding behaviors. For illustration, an example application of the system for safe egress design is provided.

A Multi-Agent Based Simulation Framework for the Study of Human and Social Behavior in Egress Analysis

There exist a wide variety of computational tools for the simulation and design of exits. However, due to the scarcity of behavioral data, these tools rely heavily on the assumptions about human individual and social behaviors. Many of these assumptions have been found inconsistent or incorrect. This paper presents a multi-agent based framework for studying human and social behavior during building emergency evacuations. A prototype system has been developed, which is able to demonstrate some emergent human social behaviors, such as competitive, queuing, and herding behaviors.

A performance-based approach to wheelchair accessible route analysis

Abstract This paper presents a method to determine if a usable wheelchair accessible route in a facility exists using motion-planning techniques. We use a ‘performance-based’ approach to predict the performance of a facility design against requirements of a building code. This approach has advantages over the traditional ‘prescriptive’ code-based approach for assessing acceptability of designs, which is normal practice today for assessing wheelchair accessibility. The prescriptive method can be ambiguous, contradictory, complex, and unduly restrictive in practice, and it can be ad hoc and difficult to implement as a computer application. The performance-based approach directly models the actual possible behaviors of an artifact (in this case, wheelchair motion) that are related to the functional intent of the designed system (a building) and (hopefully) to the specification of a prescriptive building code. This paper presents example cases from architectural practice to illustrate the use of robot motion-planning techniques for wheelchair accessibility analysis. This application is an example of using modern computational methods in support of knowledge-intensive engineering. The simulation method has broad applicability within engineering design. We illustrate and discuss how to analyze virtual simulations of the detailed behavior of a designed artifact in order to assess its use by intended users.

Compliance Analysis for Disabled Access

Accessibility regulations are federally enacted by the Americans with Disabilities Act (ADA). Design of buildings and facilities must comply with the guidelines developed by the authors of ADA. This chapter discusses a hybrid approach using encoding prescriptive-based provisions and supplementing them with performance-based methods to support compliance and usability analysis for accessibility. The hybrid compliance analysis approach is applied to analyse a facility floor plan as a case example.

Using motion planning to determine the existence of an accessible route in a CAD environment.

ABSTRACT We describe an algorithm based on motion-planning techniques to determine the existence of an accessible route through a facility for a wheeled mobility device. The algorithm is based on LaValles work on rapidly exploring random trees and is enhanced to take into consideration the particularities of the accessible route domain. Specifically, the algorithm is designed to allow performance-based analysis and evaluation of a facility. Furthermore, the parameters of a wheeled mobility device can be varied without recompilation, thus allowing standards writers, facility designers, and wheeled mobility device manufacturers to vary them accordingly. The algorithm has been implemented in a computer tool that works within a computer-aided design and drafting environment.

Emergence of Distributed Engineering Web Services

This paper presents the basic concepts of the web services technology and its potential applications in Civil Engineering. There are various communication protocols that are now available for building distributed engineering web services. This paper presents three example applications utilizing some of these protocols. These examples are employed to demonstrate that the web service approach is a promising paradigm for integrating large engineering software applications.

A Distributed Object Component-Based Approach to Large-Scale Engineering Systems and an Example Component Using Motion Planning Techniques for Disabled Access Usability Analysis

This paper introduces a large-scale engineering systems distributed object framework that serves as the connecting infrastructure between individual engineering tools and analysis components. The framework can incorporate software services as well as hardware solutions. Implemented software services include motion planning simulations and animation visualizations. Hardware solutions include the ability to incorporate devices to manipulate either remote software or hardware services. The success on such a framework relies on two levels of knowledge: understanding the underlying concepts that facilitate the component-to-component communication and the domain-specific knowledge to implement a particular service. As an example of a domain-specific service, the paper describes a motionplanning-based disabled access usability service that attempts to find accessible routes in a facility. Introduction Currently, Architecture/Engineering/Construction (AEC) information technology (IT) firms are developing specialized information-exchange solutions for domainspecific problems, and standardization enables users ubiquitous access to these tools. Indeed, these solutions use at least one level of Internet-based standard protocols: all firms are leveraging World Wide Web technology, and some firms are beginning to 1 Graduate Student, Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, csh@galerkin.stanford.edu 2 Senior Research Associate, Center for Integrated Facility Engineering, Stanford University, Stanford, CA 94305, kunz@cive.stanford.edu 3 Professor, Department of Civil and Environmental Engineering, Stanford University, Stanford, CA 94305, law@cive.stanford.edu 1 Han, Kunz, Law leverage standard distributed object paradigms. However, the implementation of large-scale and interoperable engineering systems will require the development and adherence to a third layer of standard protocols built on top of the distributed object technology. A distributed object environment provides the underlying application-toapplication communication protocol allowing an application to access the services of other applications as if these services were part of the original application, a feature known as object location transparency. This paradigm provides the facility for development of computing environments across heterogeneous platforms. Benefits include the optimization of services on specific computing platforms and taking advantage of unused or under-utilized computing resources. Most importantly, distributed object applications now act as individual but inter-communicating components that can be aggregated to form the multiple and coordinated layers of large-scale systems. This protocol must be general enough to accommodate and anticipate future engineering-specific needs to build large-scale systems on a component-by-component basis but robust enough to be truly useful for engineeringspecific services. This paper introduces a distributed object framework that serves as the connecting infrastructure between individual engineering tools and analysis components. The framework can incorporate software services as well as hardware solutions. Implemented software services include motion planning simulations and animation visualizations. Hardware solutions include the ability to incorporate devices to manipulate either remote software or hardware services. The distributed object paradigm does not distinguish between local and remote access of components that can either be software applications or hardware devices. As an example component service that integrates into the large-scale framework, the paper describes a disabled access usability analysis service. This development of this component represents a domain-specific problem that is dependent on the developer’s knowledge of the domain. Specifically, the paper describes the application of motion-planning techniques used to determine accessible routes in a facility. The Engineering Analysis Component-based Distributed Object Framework This research uses the concepts developed in (Han99) and reifies notion of a service. To fully-leverage the power of the Internet, engineering and design services should be able to interact in a formal yet flexible manner. Services should be able to combine existing services to provide added functionality. The distributed object environment provides object transparency—an application accesses a Service object using the same protocol regardless of the object’s location, either local or remote, and independent of the computer system platform assuming the platform supports the Service object interface.