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The study was conducted to ascertain demolition contractors' perceptions of the primary impediments to the widespread salvage of wood structural components for reuse or recycling. Assessment of the attitudes of demolition contractors was chosen since their participation in the salvage and reuse of materials is a key component necessary for any program to reduce the waste disposal rate of demolition debris. The insights obtained from the study can be used to facilitate future planning and design of programs and research that advance the recycling of demolition debris. A sample of contractor members of the National Demolition Association was surveyed for the study. In addition to demolition contractors' perception of impediments to salvage of wood structural components, the survey instrument provided a significant volume of descriptive information about demolition companies operating in the continental United States.

In recent years there has been increasing interest in innovative design and construction of sustainable highperformance buildings. Among the innovative techniques proposed to increase building performance is to dynamically sense, control and manage the ambient building environment, such as temperature, humidity, air quality, artificial lighting, etc. through the installation of a distributed wireless sensor network (WSN). It has been reported that such an intelligent building monitor and control system can result in an approximately 20% savings in energy usage, a substantial step toward the realization of smart building management. In conventional WSNs, battery power is used to energize these micro-scale sensors. The small space permitted for battery integration in these miniaturized systems is a limiting factor. The small battery will be quickly depleted requiring frequent battery replacement or the WSN system will cease operation. Frequent battery replacement is impractical due to the tremendous number of sensor nodes embedded in a typical WSN system. This key design challenge in WSN based building monitoring and control must be overcome in order to significantly prolong the life of the overall system operation. In this paper, the authors investigate the construction of a novel WSN system for intelligent building environment monitoring powered through the use of micro-scale thermoelectric generators (TEG). In the TEG, the ambient thermal gradient between two surfaces of the device is converted into electrical energy. To verify the feasibility of the proposed idea, an experiment was conducted and the results demonstrated the concept of harvesting ambient thermal energy to power wireless sensors.

Because of the fragmented nature of construction industry inter-organizational communication, construction industry stakeholders must rely on information exchanges in order to produce new information and directives for the process. This communication process does not always happen smoothly due to possible barriers during the information flow. The purpose of this study is to understand these potential information flow barriers and to use concept maps to engage students in discussions about communication within the construction industry. Concept map activities performed with industry professionals and senior construction management students in separate phases are described. To complement the concept map findings, interviews with key professional stakeholders provide further depth on reasons for potential communication barriers in the construction industry. Findings from this study indicate that students' lack a thorough understanding of the holistic communication process and information flow that is critical to many construction project stakeholders. Guidelines are suggested for the use of concept maps as an educational activity that is engaging to students and will enhance their knowledge of information flows in the construction process.