Collection of schedule quality metrics and application to projects of the office of facilities planning and construction (OFPC)

textConstruction projects are costly, time-consuming, and complex so that a sound plan is essential to execute them successfully. Schedules play a key role as a roadmap that shows how and when a project delivers its products defined in the project scope (PMI 2007). In an effort to facilitate scheduling process, diverse scheduling software programs have been developed and used. Nevertheless, substantial knowledge, experience, and efforts are still required to create a quality schedule. As such, many government agencies and professional organizations have recommended a variety of important concepts, metrics, and thresholds to help contractors develop decent baseline schedules and help owners check their quality. The first objective of this research is to compile, select, and organize the recommended schedule quality metrics and thresholds as tools for checking and improving the quality of baseline schedules. The second objective is to apply these metrics to baseline schedules used for the Office of Facilities Planning and Construction (OFPC) projects on the campus of the University of Texas at Austin and analyze the evaluation findings to provide recommendations for future projects. Through an extensive literature review, 11 publications from 10 government agencies and professional organizations have been studied and 49 baseline schedule quality metrics and thresholds are compiled and selected. These metrics are divided into 9 groups; General, Milestone, Duration, Calendar, Logic, Constraint, Float, Lag, and Lead. Followed was the evaluation of the baseline schedules used for OFPC projects by these metrics and thresholds to provide recommendations for future projects. The evaluation results show that every project passed 27 metrics while at least one project failed to pass 22 metrics. The majority of projects, 7 out of 13, missed 11 tests. These tests are associated with maximum duration limit (30 work days), high total float (44 work days), maximum total float (total float on the longest path + 45 work days), ratio of detail tasks to milestones, percentage of tasks on the critical path, number of lags, unique task names, open ends, extreme total float (120 work days), relationship type, and milestones missing a predecessor or successor. With regards to recommendations for future OFPC projects, emphasis is placed on the metrics that the majority of projects failed to pass as well as that are regarded as crucial for reviewing schedules.Civil, Architectural, and Environmental Engineerin

Efficient terahertz generation in highly nonlinear organic crystal HMB-TMS

We report on generation of strong and broadband terahertz (THz) pulses via collinearly phase-matched optical rectification of near-infrared femtosecond pulses in the organic nonlinear optical HMB-TMS (2-(4-hydroxy-3-methoxystyryl)-3-methylbenzo[d]thiazol-3-ium 2,4,6-trimethylbenzenesulfonate) single crystals which exhibit optimal molecular orientation and large macroscopic optical nonlinearity for efficient THz wave generation. Single-cycle THz pulses with a peak electric field strength of 0.66 MV/cm and a bandwidth from 0.1 to 5.4 THz are achieved from an HMB-TMS crystal with only a 2-mm clear aperture pumped by 1350 nm pulses at moderate fluences. The generated THz energy is about 1 µJ and the corresponding pump-to-THz energy conversion efficiency reaches 0.23%.United States. Office of Naval Research (N00014-13-1-0509)United States. Office of Naval Research. Defense University Research Instrumentation Program (N00014-15-1-2879)Samsung Global Research Outreach ProgramNational Research Foundation of Korea (No. 2016R1A2B4011050National Research Foundation of Korea (No. 2014R1A5A1009799)National Research Foundation of Korea (No. 2015K1A3A1A14004646)National Research Foundation of Korea (No. 2009-0093826

Facile Synthesis of Bumpy-Structured ZnO-ZnS Core-Shell Microspheres with Enhanced Photocatalytic Performance

Zinc oxide is considered an outstanding photocatalyst candidate, but its low photo-corrosion resistance is a problem to be solved. In the ZnO-ZnS core-shell structure, ZnS acts as a protective layer for the ZnO core, and thus, it can enhance stability and long-term performance. The ZnO-ZnS core-shell structure is synthesized into various nanoscale morphologies with high specific surface areas to improve photocatalytic efficiency. However, they are easily agglomerated and are hard to separate from reaction media. In this study, micro-sized bumpy spheres of ZnO-ZnS core-shell structure were prepared via facile chemical transformation of as-prepared ZnO. After sulfurization of the ZnO template, it was confirmed through SEM, TEM, EDS, and XPS analysis that a uniform ZnS shell layer was formed without significant change in the initial ZnO morphology. The ZnO-ZnS core-shell microsphere has shown superior efficiency and stability in the photocatalytic degradation of Rhodamine B compared with pristine ZnO microsphere

Wearasound : Beyond Visual Centric Interaction - Designing Sound for Enhancing Visual Contents

<p>The appropriate use of sounds has the potential to add a great deal to convey information in interactive commodities. Sound is a largely unexplored medium as a design element in interaction design community, even though it plays an integral role in our everyday encounters with the world, on that complementary to vision. However, information and data are predominantly represented in visual form. I argue that sound should be used in designing interactive commodities as a way to improve and enhance visual experience of the artifact. Such strategy leads to build sound design guideline and framework to help designers who are not familiar with sound design. The first half of this project focuses on revealing potentials of sounds, where sound can be used and sound design methodological point of view. These ideas are instantiated in the Wearasound, a wearable auditory device for conveying contextual information in real time without distraction. Wearasound is designed to be used while the user is moving. A range of auditory information provide peripheral awareness and indirect interaction. Delivering information is adaptive and context sensitive; appropriate information is presented as more or less obtrusive based on user’s situated context. Preliminary user evaluation suggest that audio is an appropriate medium for conveying certain domains of information (particularly for content that is intrinsically voice/audio) in specific usage context (when the user’s hands or eyes are busy).</p

Automated Program Repair from Fuzzing Perspective

In this work, we present a novel approach that connects two closely-related topics: fuzzing and automated program repair (APR). The paper is divided into two parts. In the first part, we describe the similarities between fuzzing and APR both of which can be viewed as a search problem. In the second part, we introduce a new patch-scheduling algorithm called Casino, which is designed from a fuzzing perspective to enhance search efficiency. Our experiments demonstrate that Casino outperforms existing algorithms. We also promote open science by sharing SimAPR, a simulation tool that can be used to evaluate new patch-scheduling algorithms

A case study of activity-based costing in allocating rebar fabrication costs to projects

How to improve cost allocation for reinforced steel bar (rebar) is an ongoing topic of debate among construction manufacturers and contractors. Traditionally, many fabrication shops have used a single overhead-cost pool accounting system. However, a new costing method, activity-based costing (ABC), may provide more advantages than the traditional system. In this case study, a single overhead-cost pool system is compared with the ABC method to demonstrate how ABC improves cost allocation and provides other benefits. The case study findings indicate that ABC provides such benefits as (1) accurate manufacturing costs; (2) cost information on processes; and (3) information on cost drivers. This paper also bridges the construction and cost accounting literature. Our study contributes to the construction management literature by offering a different cost allocation method to refine fabrication costs assigned to projects. The findings are expected to serve as a reference for industry professionals who recognize the shortcomings of a traditional single overhead-cost pool system and are in need of a more accurate costing system.Rebar fabrication, activity-based costing, overhead cost allocation,