Automating the Generation of Construction Checklists

Construction inspection is a critical component of INDOT’s quality assurance (QA) program. Upon receiving an inspection notice/assignment, INDOT inspectors review the plans and specifications to identify the construction quality requirements and conduct their inspections accordingly. This manual approach to gathering inspection requirements from textual documents is time-consuming, subjective, and error-prone. This project addresses this critical issue by developing an inspection requirements database along with a set of tools to automatically gather the inspection requirements and provide field crews with customized construction checklists during the inspection with the specifics of what to check, when to check, and how to check, as well as the risks and the actions to take when noncompliance is encountered. This newly developed toolset eliminates the manual effort required to acquire construction requirements, which will enhance the efficiency of the construction inspection process at INDOT. It also enables the incorporation of field-collected data to automate future compliance checking and facilitate construction documentation

Measurement-based Close-in Path Loss Modeling with Diffraction for Rural Long-distance Communications

In this letter, we investigate rural large-scale path loss models based on the measurements in a central area of South Korea (rural area) in spring. In particular, we develop new close-in (CI) path loss models incorporating a diffraction component. The transmitter used in the measurement system is located on a hill and utilizes omnidirectional antennas operating at 1400 and 2250 MHz frequencies. The receiver is also equipped with omnidirectional antennas and measures at positions totaling 3,858 (1,262 positions for LOS and 2,596 positions for NLOS) and 4,957 (1,427 positions for LOS and 3,530 positions for NLOS) for 1400 and 2250 MHz, respectively. This research demonstrates that the newly developed CI path loss models incorporating a diffraction component significantly reduce standard deviations (STD) and are independent of frequency, especially for LOS beyond the first meter of propagation, making them suitable for use with frequencies up to a millimeter-wave.Comment: 5 pages, 5 figure

Piezoelectric and Magnetoelectric Thick Films for Fabricating Power Sources in Wireless Sensor Nodes

In this manuscript, we review the progress made in the synthesis of thick film-based piezoelectric and magnetoelectric structures for harvesting energy from mechanical vibrations and magnetic field. Piezoelectric compositions in the system Pb(Zr,Ti)O3–Pb(Zn1/3Nb2/3)O3 (PZNT) have shown promise for providing enhanced efficiency due to higher energy density and thus form the base of transducers designed for capturing the mechanical energy. Laminate structures of PZNT with magnetostrictive ferrite materials provide large magnitudes of magnetoelectric coupling and are being targeted to capture the stray magnetic field energy. We analyze the models used to predict the performance of the energy harvesters and present a full system description

Tumor Microenvironment on a Chip: The Progress and Future Perspective

Tumors develop in intricate microenvironments required for their sustained growth, invasion, and metastasis. The tumor microenvironment plays a critical role in the malignant or drug resistant nature of tumors, becoming a promising therapeutic target. Microengineered physiological systems capable of mimicking tumor environments are one emerging platform that allows for quantitative and reproducible characterization of tumor responses with pathophysiological relevance. This review highlights the recent advancements of engineered tumor microenvironment systems that enable the unprecedented mechanistic examination of cancer progression and metastasis. We discuss the progress and future perspective of these microengineered biomimetic approaches for anticancer drug prescreening applications

Selective and efficient extraction of Nd from NdFeB magnets via ionization in LiCl-KCl-CdCl2 melt

The growing popularity of NdFeB magnets has created a demand for sustainable Nd recycling processes with fewer byproducts and higher extraction efficiencies. To address this need, we herein studied the extraction of Nd from NdFeB magnets via selective ionization in CdCl2-LiCl-KCl at 773 K. When the CdCl2 content was sufficiently large to completely ionize Nd into Nd3+ > 99% of Nd was selectively extracted into the salts within 2 h, while Fe and B remained in the solid phase. The microstructural and compositional changes of the magnet and salts were examined by scanning electron microscopy coupled with energy-dispersive X-ray spectroscopy and by inductively coupled plasma-optical emission spectrometry. In the presence of CdCl2, the magnet was naturally fragmented and pulverized. Correlations between CdCl2 content and cyclic voltammetry data (peak current density and peak potential) were established and validated to monitor the reaction progress on-line, and the maximum correlation errors for peak current density and peak potential were found to be less than 8.33% and 16.1%, respectively. Finally, the results of this study were combined with those of previous works to propose a novel Nd recycling process based on molten salt usage. (C) 2020 Elsevier B.V. All rights reserved

Effects of NiCl2 and FeCl2 additives on the anodic dissolution behaviours of Inconel 600 in molten LiCl???KCl salts

The anodic dissolution behaviour of Inconel 600 must be elucidated to design an efficient decontamination process for used nuclear steam generator tubes with radioactive nuclide depositions in their surface microcracks. We investigated the effects of NiCl2 and FeCl2 additives in LiCl???KCl eutectic salts on the microstructural changes in Inconel 600 during electrolytic decontamination. A Cr???Fe depletion layer formed on Inconel 600 via Ni reduction at the position where alloying elements oxidised. In the FeCl2-added salt, the selective dissolution of active alloying elements through the grain boundary produced a cavity-cluster layer whose shape was changed using applied electrochemical methods

Risk-Based Inspection

SPR No. 750Construction inspection is a critical component of the quality assurance/quality control (QA/QC) program at the South Carolina Department of Transportation (SCDOT). A pressing challenge SCDOT has been facing is to balance the increasing demand to rebuild the statewide transportation systems with declining resources available for inspection. This project aims to address this critical issue by developing a risk-based inspection program that includes (1) the identification and assessment of risks associated with construction activities at SCDOT, (2) the development of inspection strategies that correspond to the level of risk, (3) the identification of quality requirements and inspection activities that are applicable to pay items, and (4) the design and implementation of a digital, risk-based inspection system. Two rounds of surveys were conducted to first identify and rank the risk factors and then assess the risks in aspects of likelihood, severity (cost, time, safety, and quality), and performance (short-/mid-/long-term). An aggregate risk score was calculated to categorize each pay item into high, medium, and low levels of risk. The inspection strategies (i.e., inspection priority and frequency and documentation frequency) were designed to correspond to the level of risk. The quality requirements and inspection activities for pay items were extracted from the corresponding sections in the standard specification, construction manual, supplementary specifications, supplementary technical specifications, and standard drawings. A database was designed to host the risk and inspection information. Tools were developed to assist project engineers and field inspectors in retrieving inspection activities in the digital form of checklists. The main deliverable is the resulting digital inspection system with tools. This system allows for the retrieval of all the related risk information, inspection strategy, and inspection activities/checklists for any given pay item. This system is expected to significantly enhance the efficiency of the construction inspection practice at SDCOT and reduce the workload for construction inspectors. The risk-based approach also enables SCDOT to focus on the most critical areas and can support the automation of construction inspection at SCDOT

Data-Driven Analysis for Facility Management in Higher Education Institution

Planned Preventive Maintenance (PPM) and Unplanned Maintenance (UPM) are the most common types of facility maintenance. This paper analyzes current trends and status of Facility Management (FM) practice at higher education institutions by proposing a systematic data-driven methodology using Natural Language Process (NLP) approaches, statistical analysis, risk-profile analysis, and outlier analysis. This study utilizes a descriptive database entitled Facility Management Unified Classification Database (FMUCD) to conduct the systematic data-driven analyses. The 5-year data from 2015 to 2019 was collected from eight universities in North America. A preprocessing step included but was not limited to identifying common data attributes, cleaning noisy data, and removing unnecessary data. The outcomes of this study can facilitate the decision-making process by providing an understanding of various aspects of educational facility management trends and risks. The methodology developed gives decision makers of higher education institutions, including facility managers and institution administrators, effective strategies to establish long-term budgetary goals, which will lead to the enhancement of the asset value of the institutions