The IT performance evaluation in the construction industry

To date there has been limited published work in the construction management and engineering literature that has provided empirical evidence to demonstrate that IT can improve organizational performance. Without an explicit understanding about how IT can be effectively used to improve organizational performance, its justification will remain to be weak for managers. To ensure the continuous increase in IT based applications in the construction industry, sufficient evidence has to be provided for management in various professions of the construction industry to evaluate, allocate and utilize appropriate IT systems. In an attempt to explore the relationship between IT and productivity, an empirical investigation of 60 Professional Consulting Firms (PCF) from the Hong Kong construction industry was undertaken. A model for determining the organizational productivity of IT is proposed, and the methodology used to test the model is described. The findings are analyzed and a cross-profession comparison of the results indicated the differences in the use of IT. The research findings are discussed with similarities being drawn. The limitations of the research are then presented and discussed. The implications of the findings and conclusions then fully presented

The Effective Potential And Additional Large Radius Compactified Space-Time Dimensions

The consequences of large radius extra space-time compactified dimensions on the four dimensional one loop effective potential are investigated for a model which includes scalar self interactions and Yukawa coupling to fermions. The Kaluza-Klein tower of states associated with the extra compact dimensions shifts the location of the effective potential minimum and modifies its curvature. The dependence of these effects on the radius of the extra dimension is illustrated for various choices of coupling constants and masses. For large radii, the consequence of twisting the fermion boundary condition on the compactified dimensions is numerically found to produce but a negligible effect on the effective potential.Comment: 14 pages, LaTeX, 6 Postscript figure

Net energy analysis of solar and conventional domestic hot water systems in Melbourne, Australia

It is commonly assumed that solar hot water systems save energy and reduce greenhouse gas emissions. Very rarely has the life-cycle energy requirements of solar hot water systems been analysed, including their embodied energy. The extent to which solar hot water systems save energy compared to conventional systems in Melbourne, Australia, is shown through a comparative net energy analysis. The solar systems provided a net energy saving compared to the conventional systems after 0.5 to 2 years, for electricity and gas systems respectively.<br /

Leaving More Than Money: Mediation Clauses in Estate Planning Documents

When probate disputes arise, an increasing number of courts have been referring those disputes to mediation. Estate planners, however, have been less proactive about drafting wills to include mediation clauses that would anticipate estate disputes and channel them away from litigation. When a will mandates mediation, the will provides a dispute resolution mechanism designed to preserve family harmony, conserve estate assets, and avoid airing the family\u27s dirty laundry -objectives common to many testators. Mediation clauses in wills are no panacea. They are of little value to testators who exalt control over estate assets above all other concerns, and they are unlikely to bind disappointed family members whose primary claim is against the will rather than under the will. Nevertheless, compared to other alternatives frequently employed by estates lawyers (including no contest clauses), mediation clausesp resent significantp otentialf or reducing estates litigation, with its attendant financial and emotional costs

Multistability of free spontaneously-curved anisotropic strips

Multistable structures are objects with more than one stable conformation, exemplified by the simple switch. Continuum versions are often elastic composite plates or shells, such as the common measuring tape or the slap bracelet, both of which exhibit two stable configurations: rolled and unrolled. Here we consider the energy landscape of a general class of multistable anisotropic strips with spontaneous Gaussian curvature. We show that while strips with non-zero Gaussian curvature can be bistable, strips with positive spontaneous curvature are always bistable, independent of the elastic moduli, strips of spontaneous negative curvature are bistable only in the presence of spontaneous twist and when certain conditions on the relative stiffness of the strip in tension and shear are satisfied. Furthermore, anisotropic strips can become tristable when their bending rigidity is small. Our study complements and extends the theory of multistability in anisotropic shells and suggests new design criteria for these structures.Comment: 20 pages, 10 figure

Nonaffine Correlations in Random Elastic Media

Materials characterized by spatially homogeneous elastic moduli undergo affine distortions when subjected to external stress at their boundaries, i.e., their displacements \uv (\xv) from a uniform reference state grow linearly with position \xv, and their strains are spatially constant. Many materials, including all macroscopically isotropic amorphous ones, have elastic moduli that vary randomly with position, and they necessarily undergo nonaffine distortions in response to external stress. We study general aspects of nonaffine response and correlation using analytic calculations and numerical simulations. We define nonaffine displacements \uv' (\xv) as the difference between \uv (\xv) and affine displacements, and we investigate the nonaffinity correlation function $\mathcal{G} =$ and related functions. We introduce four model random systems with random elastic moduli induced by locally random spring constants, by random coordination number, by random stress, or by any combination of these. We show analytically and numerically that $\mathcal{G}$ scales as A |\xv|^{-(d-2)} where the amplitude $A$ is proportional to the variance of local elastic moduli regardless of the origin of their randomness. We show that the driving force for nonaffine displacements is a spatial derivative of the random elastic constant tensor times the constant affine strain. Random stress by itself does not drive nonaffine response, though the randomness in elastic moduli it may generate does. We study models with both short and long-range correlations in random elastic moduli.Comment: 22 Pages, 18 figures, RevTeX

Fluorescence Imaging of Underexpanded Jets and Comparison with CFD

An experimental study of underexpanded and highly underexpanded axisymmetric nitrogen free jets seeded with 0.5% nitric oxide (NO) and issuing from a sonic orifice was conducted at NASA Langley Research Center. Reynolds numbers based on nozzle exit conditions ranged from 770 to 35,700, and nozzle exit-to-ambient jet pressure ratios ranged from 2 to 35. These flows were non-intrusively visualized with a spatial resolution of approximately 0.14 mm x 0.14 mm x 1 mm thick and a temporal resolution of 1 s using planar laser-induced fluorescence (PLIF) of NO, with the laser tuned to the strongly-fluorescing UV absorption bands of the Q1 band head near 226.256 nm. Three laminar cases were selected for comparison with computational fluid dynamics (CFD). The cases were run using GASP (General Aerodynamic Simulation Program) Version 4. Comparisons of the fundamental wavelength of the jet flow showed good agreement between CFD and experiment for all three test cases, while comparisons of Mach disk location and Mach disk diameter showed good agreement at lower jet pressure ratios, with a tendency to slightly underpredict these parameters with increasing jet pressure ratio

Elastic Instability Triggered Pattern Formation

Recent experiments have exploited elastic instabilities in membranes to create complex patterns. However, the rational design of such structures poses many challenges, as they are products of nonlinear elastic behavior. We pose a simple model for determining the orientational order of such patterns using only linear elasticity theory which correctly predicts the outcomes of several experiments. Each element of the pattern is modeled by a "dislocation dipole" located at a point on a lattice, which then interacts elastically with all other dipoles in the system. We explicitly consider a membrane with a square lattice of circular holes under uniform compression and examine the changes in morphology as it is allowed to relax in a specified direction.Comment: 15 pages, 7 figures, the full catastroph