An examination of the building materials sector raised two critical questions: Why do more firms in the building materials sector not attempt to directly gauge end-users' preferences? And, why do many materials pr...
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An examination of the building materials sector raised two critical questions: Why do more firms in the building materials sector not attempt to directly gauge end-users' preferences? And, why do many materials producers employ self-limiting definitions of building materials? The sector was analyzed using transaction cost economics and network theory. A framework was then developed for materials development and innovation. The role of a key actor in the framework, the researcher, was illustrated through a materials study performed in a developing country. In concluding, it is suggested the framework could be used to expand the study, expand markets for the producer and strengthen producer-researcher links. (C) 2005 Elsevier B.V. All rights reserved.
In the past 10 years, integrated land use and transportation modeling has received considerable attention in the scholarly literature. This academic interest is slowly yielding practical applications. In the USA, many...
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In the past 10 years, integrated land use and transportation modeling has received considerable attention in the scholarly literature. This academic interest is slowly yielding practical applications. In the USA, many metropolitan planning organizations (MPOs) and state departments of transportation are beginning to implement these types of model for the first time. While many improvements have been made to these models, and the value of these improvements should not be understated, much work stilt remains. One of the most challenging problems in land use modeling is how floorspace (buildings) is built and occupied. The purpose of this article is twofold: first, to draw attention to insufficiencies in the representation of floorspace developer behavior-particularly as it applies to large, urban-edge projects - within current integrated land use and transportation models and, second, to determine the necessity of explicitly accounting for such projects within these models. The Sacramento MEPLAN model will be used together with historical development records to demonstrate and test these assertions. Single large developments are modeled with a common year of development, size, and location. Among the findings, large developments are fairly common in the Sacramento region and make up a considerable amount of floorspace development in absolute terms, large basic sector developments have more of an impact and are therefore more important to explicitly account for than are large non-basic sector developments. A single large basic sector development modeled in a 20-year forecast has a significant impact on zonal outputs. Recommendations are put forward regarding the use of this research in practical modeling exercises.
This paper is about a series of three Case Studies done primarily by 5 th and 6th year students of architectural design at UNL under the auspices of the AIA Case Studies Initiative. The first (First National Bank of O...
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ISBN:
(纸本)0784407983
This paper is about a series of three Case Studies done primarily by 5 th and 6th year students of architectural design at UNL under the auspices of the AIA Case Studies Initiative. The first (First National Bank of Omaha) was completed in the summer of 2004 and was successfully submitted and selected as one of only seven case studies on the national AIA web page (***/ed_case studies). A second Case Study was completed (Durham Research Center at UNMC, Omaha) in the summer of 2005, and has been submitted to the AIA Case Studies Initiative. We are awaiting notification if it has been selected for inclusion on the national web page. A third Case Study beginning this spring 2006 will study the Peter Kiewit Institute of Information Science, Technology and Engineering at UNO, Omaha. This paper discusses the highlights of these two completed Case Studies from the perspective of the faculty, the students and the large firms themselves, and discusses lessons learned and preparations for the third Case Study in the spring semester 2006, to be submitted in the summer as well. Copyright ASCE 2006.
In this paper, we propose a method for non-contact measurement of knee load. Joint position data is acquired with image analysis. Masses and centers of gravity on each segment of human body is estimated with a multipl...
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In this paper, we propose a method for non-contact measurement of knee load. Joint position data is acquired with image analysis. Masses and centers of gravity on each segment of human body is estimated with a multiple linear regression model. Knee torque is estimated based on kinetics and these data, and it is used index value of knee load. In the proposing method, human body is not restricted and measurement may be performed in a ordinary space without any special equipment set on the floor or wall. The method is effective for preventing knee injuries. The validity of the proposing method is verified with cross-correlation function between the estimated knee load and EMG signals. The knee load increases along with the knee flexion and extension, and is sustained by the torque around the knee exerted by the quadriceps femoris. EMG signal measured on the quadriceps femoris is also index value of knee load. The experiments are performed based on those data. As a result, it is reported that the time derivative of the torque corresponds to the EMG signals in the sense of phase.
A diffusion equation model which has been recently applied to room‐acoustic prediction is used to model the sound field in urban squares surrounded by diffusively reflecting building facades. A previous diffusion equ...
A diffusion equation model which has been recently applied to room‐acoustic prediction is used to model the sound field in urban squares surrounded by diffusively reflecting building facades. A previous diffusion equation model [V. Valeau, et. al., J. Acoust. Soc. Am., 119, 2006, pp. 1504–1513; Y. Jing and N. Xiang, J. Acoust. Soc. Am. 121, 2007, pp. 3284–3287; A. Billon, et. al., Applied Acoustics, 2007, in print] is more suitable for room surfaces with low and medium absorption coefficient, whereas in this case the space is featured with an open top characterized by the absorption coefficient 1.0. Another diffusion equation model [T. Polles, et. al., J. Acoust. Soc. Am., 116, 2004, pp. 2969–2983] can well model the sound field in a space where one specific dimension is larger than the others, like street. However, it has not yet been extended for urban squares. A modified diffusion equation model is proposed for modeling the sound field in urban squares. Both simulations and scale‐model experiments are employed to investigate its effectiveness in terms of the reverberation time and sound pressure level distribution.
Coded signals have been increasingly applied in acoustical/bio‐ultrasonic measurements in order to increase the measurement quality or to cope with demanding requirements [Xiang and Schroeder (2003)]. Increasing inte...
Coded signals have been increasingly applied in acoustical/bio‐ultrasonic measurements in order to increase the measurement quality or to cope with demanding requirements [Xiang and Schroeder (2003)]. Increasing interest in coded signals as acoustical excitations has prompted development of efficient correlation algorithms [Daigle and Xiang, J. Acoust. Soc. Am. (2006)]. These algorithms allow efficient processing of complex‐valued sequences as needed in critical acoustical measurements, such as using simultaneous sources. Exploiting excellent correlation properties of some coded signals, this work applies complex‐valued quadratic residue (QR) sequences and Zech‐logarithm sequences in both base‐band acoustical channel measurements using sequential excitations and band‐limited acoustical channel measurements using amplitude‐modulation schemes. Numerical simulations and laboratory experiments carried out in this work demonstrate feasibility of the techniques. This paper discusses advantages and challenges when using coded excitations in potential acoustical applications.
Background: The economic and biological implications of plant invasion are overwhelming;however, the processes by which plants become successful invaders are not well understood. Limited genetic resources are availabl...
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Background: The economic and biological implications of plant invasion are overwhelming;however, the processes by which plants become successful invaders are not well understood. Limited genetic resources are available for most invasive and weedy species, making it difficult to study molecular and genetic aspects that may be associated with invasion. Results: As an initial step towards understanding the molecular mechanisms by which plants become invasive, we have generated a normalized Expressed Sequence Tag ( EST) library comprising seven invasive populations of Centaurea maculosa, an invasive aster in North America. Seventy- seven percent of the 4423 unique transcripts showed significant similarity to existing proteins in the NCBl database and could be grouped based on gene ontology assignments. Conclusion: The C. maculosa EST library represents an initial step towards looking at gene-specific expression in this species, and will pave the way for creation of other resources such as microarray chips that can help provide a view of global gene expression in invasive C. maculosa and its native counterparts. To our knowledge, this is the first published set of ESTs derived from an invasive weed that will be targeted to study invasive behavior. Understanding the genetic basis of evolution for increased invasiveness in exotic plants is critical to understanding the mechanisms through which exotic invasions occur.
This paper presents new structural analysis tools based on limit state analysis for vaulted masonry buildings. Thrust lines are used to visualize the forces within the masonry and to predict possible collapse modes. T...
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This paper presents new structural analysis tools based on limit state analysis for vaulted masonry buildings. Thrust lines are used to visualize the forces within the masonry and to predict possible collapse modes. The models are interactive and parametric to explore relationships between building geometry and possible equilibrium conditions in real time. Collapse analysis due to applied displacements is determined by combining kinematics and statics. The approach is largely two dimensional, though more complex three-dimensional problems are analyzed using the same methods. This paper presents a series of analytical tools that are fast and easy to use in real time, but at the same time rigorous and highly accurate. This work represents a significant improvement over traditional methods of thrust line analysis performed by hand, which are often tedious and time-consuming. (c) 2006 Elsevier Ltd. All rights reserved.
This paper summarizes a project that analyzed previous research undertaken in the upper San Pedro basin of Arizona (USA) and Sonora (Mexico). Various groups had undertaken the previous research over the past decade. A...
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This paper summarizes a project that analyzed previous research undertaken in the upper San Pedro basin of Arizona (USA) and Sonora (Mexico). Various groups had undertaken the previous research over the past decade. A literature review and an e-mail survey resulted in a list of 10 lessons for watershed planning research as well as suggested watershed planning strategies. (c) 2005 Published by Elsevier B.V.
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