Requirement

Abstract: An iterative linear stochastic pavement management model is proposed that deploys a nonhomogenous discrete-time Markov chain for predicting the future pavement conditions for a given pavement network. A nonhomogenous transition matrix is constructed to incorporate both the pavement deterioration rates and improvement rates. The pavement deterioration rates are simply the transition probabilities associated with the deployed pavement states. The improvement rates are mainly the maintenance and rehabilitation variables representing the deployed maintenance and rehabilitation actions. A decision policy is formulated to identify the optimal set of maintenance and rehabilitation actions and their respective timings, and to provide the optimal level of maintenance and rehabilitation funding over an analysis period. The nonhomogenous Markov chain allows for a distinct maintenance and rehabilitation plan ͑matrix͒ for each time interval ͑transition͒. However, the total number of ma...

This review covers mainly intumescent coatings, with briefer discussions of non-intumescent organic fire-resistive coatings and cementitious inorganic coatings. Emphasis is placed on the more recent developments, and the more recent patent literature is surveyed. Modeling and optimizing are covered both from basic and applied aspects. The chemistry of the production of a foamed char barrier is discussed. Enhancing the performance by adjuvants and choice of binders is shown to be possible. The important interactions of ammonium polyphosphate with other components such as titanium dioxide are described. Testing is briefly discussed, as are some shortcomings of present-day coatings, such as limited water resistance, and some opportunities for improvement.

Mathematical models can be used to improve performance, reduce cost of production, and reduce nutrient excretion by accounting for more of the variation in predicting requirements and feed utilization in each unique production situation. Mathematical models can be classified into five or more categories based on their nature and behavior. Determining the appropriate level of aggregation of equations is a major problem in formulating models. The most critical step is to describe the purpose of the model and then to determine the appropriate mix of empirical and mechanistic representations of physiological functions, given development and evaluation dataset availability, inputs typically available and the benefits versus the risks of use associated with increased sensitivity. We discussed five major feeding systems used around the world. They share common concepts of energy and nutrient requirement and supply by feeds, but differ in structure and application of the concepts. Animal mo...

Many Small to Medium Enterprises (SMEs) tend to gradually adopt Web based business applications to enhance their business processes. To support this gradual adoption we need a framework that supports iterative development. Further processes that have been supported by web based business applications can change and evolve requiring applications to be changed accordingly. One way to facilitate these requirements is to empower SMEs to make changes to the web application to accommodate the required changes while using that web application. This paper presents a requirement specification tool and a Use Case model of a Web based application which can be used to specify and create the Web applications. This approach will bring the formalism to ad-hoc end-user development by including requirement specification phase. In this approach an application is viewed as a collection of packages. A package consists of related set of use cases. A scope list is developed at the package level. This will assure the required functionality of the application is completely specified. This will also provide a framework to validate the requirements. We have developed this tool in Component Based Development/ Deployment System (CBEADS). Now we are in a process of testing it.

Long-span guardrail systems have been recognized as an effective means of shielding low-fill culverts. These designs are popular because, in comparison with other systems that attach posts to the top of the culvert, they are able to shield the culvert safely while creating little additional construction effort and limiting the damage to the culvert and the need for repair. However, previous long-span designs were limited by the need to use long sections of nested guardrail to prevent rail rupture and by the need for large lateral offsets between the barrier and the culvert. The Midwest Guardrail System (MGS) long-span design eliminates those two shortcomings by applying the benefits of the MGS to a long-span design. The MGS long-span design increased vehicle capture and stability because of the increased rail height, limited the potential for pocketing and wheel snag through the use of controlled-release terminal posts adjacent to the unsupported span, and greatly increased the tens...

This paper presents the methodology and findings of an international survey carried out in 1989 on the existing information needs and technical facilities of professionals in the field of construction and housing (448 responses from 92 different countries) The survey armed at the determination of future information services, and five guidelines for future database development in the area were determined, each illustrated with respondents quotations. The guidelines are (1) there is a substantial demand for an information system which allows for information exchange between professionals in the area of construction and housing: (2) for this informa tion system to be fully effective, it must be client-oriented; (3) for the system to be relevant, two approaches were suggested —the establishment of a regular horizontal information flow and the establishment of regional institutions acting as centres for information dissemination; (4) the issue of cost must be tackled since it was identif...