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2019

University of Kentucky

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Articles 1 - 30 of 97

Full-Text Articles in Engineering

Nanogaps On Atomically Thin Materials As Non-Volatile Read/Writable Memory Devices, Douglas Robert Strachan, Abhishek Sundararajan, Mathias Joseph Boland Aug 2019

Nanogaps On Atomically Thin Materials As Non-Volatile Read/Writable Memory Devices, Douglas Robert Strachan, Abhishek Sundararajan, Mathias Joseph Boland

Physics and Astronomy Faculty Patents

The present invention relates to the presence of nanogaps across a metal dispersed over an atomically-thin material, such that the nanogap exposes the atomically-thin material. The resulting device offers an ultra-short gap with ballistic transport and demonstrated switching in the presence of a gate or dielectric material in close proximity to the channel.


Thermal Interface Material, Matthew Collins Weisenberger, John Davis Craddock Jul 2019

Thermal Interface Material, Matthew Collins Weisenberger, John Davis Craddock

Center for Applied Energy Research Faculty Patents

A flexible sheet of aligned carbon nanotubes includes an array of aligned nanotubes in a free standing film form not adhered to the synthesis substrate, with a matrix infiltrated interstitially into the nanotube array with access to the nanotube tips from both the top and bottom. That is, the infiltrant is purposely limited from over-filling or coating one or both exterior top and/or bottom surfaces of the array, blocking access to the tips. A typical matrix is a polymer material.


Beneficial Reuse Of Industrial Co2 Emissions Using A Microalgae Photobioreactor: Waste Heat Utilization Assessment, Daniel T. Mohler, Michael H. Wilson, Zhen Fan, John G. Groppo, Mark Crocker Jul 2019

Beneficial Reuse Of Industrial Co2 Emissions Using A Microalgae Photobioreactor: Waste Heat Utilization Assessment, Daniel T. Mohler, Michael H. Wilson, Zhen Fan, John G. Groppo, Mark Crocker

Center for Applied Energy Research Faculty Publications

Microalgae are a potential means of recycling CO2 from industrial point sources. With this in mind, a novel photobioreactor (PBR) was designed and deployed at a coal-fired power plant. To ascertain the feasibility of using waste heat from the power plant to heat algae cultures during cold periods, two heat transfer models were constructed to quantify PBR cooling times. The first, which was based on tabulated data, material properties and the physical orientation of the PBR tubes, yielded a range of heat transfer coefficients of 19–64 W m−2 K−1 for the PBR at wind speeds of ...


Rapid Repair Of Bridge Decks In Cold Weather, Abheetha Peiris, Issam E. Harik Jul 2019

Rapid Repair Of Bridge Decks In Cold Weather, Abheetha Peiris, Issam E. Harik

Kentucky Transportation Center Research Report

Using regular concrete or mortar to repair potholes in concrete bridge decks is typically infeasible in cold weather due to extended set and curing times. However, several commercially available rapid-set repair materials can be used at temperatures near or below freezing. This study evaluated five such materials to assess their properties and determine which are most suited to executing pothole repairs in cold weather. For each material, laboratory testing evaluated set times, compressive strength gains, and bond strength to existing concrete at three temperatures: 35°F, 15°F, and 0°F (1.7°C, -9.4°C, and -17.8 ...


Truss Bridge Rehabilitation Prioritization, Abheetha Peiris, Issam E. Harik Jul 2019

Truss Bridge Rehabilitation Prioritization, Abheetha Peiris, Issam E. Harik

Kentucky Transportation Center Research Report

Kentucky’s inventory of historic steel truss bridges is declining rapidly. There are more than 150 historic truss bridges in the Kentucky Transportation Cabinet’s (KYTC) bridge inventory. Most of these bridges require maintenance to avoid replacement. However, prioritizing the rehabilitation of these bridges based on their historic importance is challenging. While AASHTO’s Guidelines for Historic Bridge Rehabilitation and Replacement contain guidance on selecting bridges for preservation, currently there is no guidance on how to prioritize those historic bridges selected for rehabilitation. Building on a previous study that identified historic truss bridges in Kentucky meriting preservation, the Kentucky Transportation ...


Method Of Development And Use Of Catalyst-Functionalized Catalytic Particles To Increase The Mass Transfer Rate Of Solvents Used In Acid Gas Cleanup, Leland R. Widger, Cameron A. Lippert, Kunlei Liu Jun 2019

Method Of Development And Use Of Catalyst-Functionalized Catalytic Particles To Increase The Mass Transfer Rate Of Solvents Used In Acid Gas Cleanup, Leland R. Widger, Cameron A. Lippert, Kunlei Liu

Center for Applied Energy Research Faculty Patents

The present invention relates to methods for improving carbon capture using entrained catalytic-particles within an amine solvent. The particles are functionalized and appended with a CO2 hydration catalyst to enhance the kinetics of CO2 hydration and improve overall mass transfer of CO2 from an acid gas.


Optimization Of Induction Quenching Processes For Hss Roll Based On Mmpt Model, Ligang Liu, Hui Yu, Zhiqiang Yang, Chunmei Zhao, Tongguang Zhai Jun 2019

Optimization Of Induction Quenching Processes For Hss Roll Based On Mmpt Model, Ligang Liu, Hui Yu, Zhiqiang Yang, Chunmei Zhao, Tongguang Zhai

Chemical and Materials Engineering Faculty Publications

To improve the comprehensive performance of high speed steel (HSS) cold rolls, the induction hardening processes were analyzed by numerical simulation and experimental research. Firstly, a modified martensitic phase transformation (MMPT) model of the tested steel under stress constraints was established. Then, the MMPT model was fed into DEFORM to simulate the induction quenching processes of working rolls based on an orthogonal test design and the optimal dual frequency of the induction quenching process was obtained. The results indicate that the depth of the roll’s hardened layer increases by 32.5% and the axial residual tensile stress also becomes ...


Synthesis Of Metal Oxide Surfaces And Interfaces With Crystallographic Control Using Solid-Liquid-Vapor Etching And Vapor-Liquid-Solid Growth, Beth S. Guiton, Lei Yu Jun 2019

Synthesis Of Metal Oxide Surfaces And Interfaces With Crystallographic Control Using Solid-Liquid-Vapor Etching And Vapor-Liquid-Solid Growth, Beth S. Guiton, Lei Yu

Chemistry Faculty Patents

The present invention provides integrated nanostructures comprising a single-crystalline matrix of a material A containing aligned, single-crystalline nanowires of a material B, with well-defined crystallographic interfaces are disclosed. The nanocomposite is fabricated by utilizing metal nanodroplets in two subsequent catalytic steps: solid-liquid-vapor etching, followed by vapor-liquid-solid growth. The first etching step produces pores, or “negative nanowires” within a single-crystalline matrix, which share a unique crystallographic direction, and are therefore aligned with respect to one another. Further, since they are contained within a single, crystalline, matrix, their size and spacing can be controlled by their interacting strain fields, and the array ...


Transient Analysis Of Diffusion-Induced Deformation In A Viscoelastic Electrode, Yaohong Suo, Fuqian Yang Jun 2019

Transient Analysis Of Diffusion-Induced Deformation In A Viscoelastic Electrode, Yaohong Suo, Fuqian Yang

Chemical and Materials Engineering Faculty Publications

In this study, we analyze the transient diffuse-induced-deformation of an electrode consisting of the conducting polymer polypyrrole (PPY) by using the theories of linear viscoelasticity and diffusion-induced stress. We consider two constitutive relationships with dependence of viscosity on strain rate: Kelvin-Voigt model and three-parameter solid model. A numerical method is used to solve the problem of one-dimensional, transient diffusion-induced-deformation under potentiostatic operation. The numerical results reveal that the maximum displacement occurs at the free surface and the maximum stress occurs at the fixed end. The inertia term causes the stress to increase at the onset of lithiation. The stress decreases ...


Bridge Load Testing Versus Bridge Load Rating, Abheetha Peiris, Issam E. Harik Jun 2019

Bridge Load Testing Versus Bridge Load Rating, Abheetha Peiris, Issam E. Harik

Kentucky Transportation Center Research Report

The current method of load rating bridges according to AASHTO specifications can underestimate the capacity and behavior of bridges. Analytical equations do not account for the degree of rigidity of the supports, unintended composite action due to friction between girders and the slab, and other factors. Load testing of individual bridges can produce a load rating that much more accurately reflects the capacity of a non-composite bridge. However, current methods of load testing require significant time commitments to instrument a bridge profile to record data, rendering it impractical in many cases. But there are new commercially available strain gauges that ...


E-Tickets And Advanced Technologies For Efficient Construction Inspections, Roy E. Sturgill, Gabriel B. Dadi, Christopher Van Dyke, Dhaviat Patel, Joshua Withrow, Clyde Wesley Newcomer Iv Jun 2019

E-Tickets And Advanced Technologies For Efficient Construction Inspections, Roy E. Sturgill, Gabriel B. Dadi, Christopher Van Dyke, Dhaviat Patel, Joshua Withrow, Clyde Wesley Newcomer Iv

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet (KYTC), like many state transportation agencies, has seen demand for high-quality infrastructure skyrocket even as it endures reductions in staff numbers. To mitigate the effects of declining staff and bolster construction efficiency, the Cabinet has experimented with a variety of e-construction technologies, the goal of which are to abolish paper-based workflows and improve project-site monitoring activities. This research investigated the performance of three e-construction technologies on KYTC pilot projects — e-ticketing, paver mounted thermal profilers, and intelligent compaction. E-ticketing reduced the amount of time needed to retrieve material tickets and facilitated comparisons of theoretical tonnages to actual ...


Review Of Non-Standard Warm Mix Asphalt Projects, Tim C. Scully Jr. Jun 2019

Review Of Non-Standard Warm Mix Asphalt Projects, Tim C. Scully Jr.

Kentucky Transportation Center Research Report

Periodically, when the Kentucky Transportation Cabinet’s (KYTC) the Division of Construction receives requests to use non-standard warm mix asphalt technologies, it may be asked to waive the temperature specification or other product specifications/processes. The short-term and long-term impacts of this waiver are not completely understood. The Division of Construction approves these requests and notes their use, however, no follow-up studies have been done to evaluate the performance of non-standard warm mix asphalt. Similarly, no previous studies have compared data on quality assurance/quality control (QA/QC) and performance for these mixtures with those of standard warm mix asphalt ...


Audubon Parkway Slab Lifting At Mp 22.75 — Bridge Approach And Departure Settlement, Tim C. Scully Jr. Jun 2019

Audubon Parkway Slab Lifting At Mp 22.75 — Bridge Approach And Departure Settlement, Tim C. Scully Jr.

Kentucky Transportation Center Research Report

The approach/departure Portland Cement Concrete (PCC) panels on the eastbound and westbound side of Audubon Parkway at MP 22.75 over route KY 2120 began to exhibit settlement and cracking in a few locations, which created an uncomfortable ride for motorists. To address this problem, the Kentucky Transportation Cabinet (KYTC) contracted with MasterDry to repair the PCC panel settlement. MasterDry claims that its two-part polyurethane material expands into a rigid foam that fills voids, stabilizes slabs, and lifts concrete. The polyurethane material is injected through 5/8-inch holes drilled in the PCC panel. Once injected, a chemical reaction converts ...


Redefining Construction As-Built Plans To Meet Current Kentucky Transportation Cabinet Needs, Victoria Lynn Lasley, Steven Waddle, Tim Taylor, Roy E. Sturgill Jr. Jun 2019

Redefining Construction As-Built Plans To Meet Current Kentucky Transportation Cabinet Needs, Victoria Lynn Lasley, Steven Waddle, Tim Taylor, Roy E. Sturgill Jr.

Kentucky Transportation Center Research Report

As-built plans have traditionally been used by construction industry practitioners to record changes made during construction. As-builts provide valuable information for new design projects as well as rehabilitation and remediation projects. The completeness and accuracy of these plans are essential for transportation industries and their success. While the importance of as-builts is widely recognized, preparing them can be difficult and time-consuming; many entities — especially public agencies — lack the resources necessary to produce accurate and detailed as-builts. After investigating the current as-built operations of state transportation agencies, Kentucky Transportation Center (KTC) researchers devised recommendations to improve the Kentucky Transportation Cabinet’s ...


Do Transportation Network Companies Decrease Or Increase Congestion?, Gregory D. Erhardt, Sneha Roy, Drew Cooper, Bhargava Sana, Mei Chen, Joe Castiglione May 2019

Do Transportation Network Companies Decrease Or Increase Congestion?, Gregory D. Erhardt, Sneha Roy, Drew Cooper, Bhargava Sana, Mei Chen, Joe Castiglione

Civil Engineering Faculty Publications

This research examines whether transportation network companies (TNCs), such as Uber and Lyft, live up to their stated vision of reducing congestion in major cities. Existing research has produced conflicting results and has been hampered by a lack of data. Using data scraped from the application programming interfaces of two TNCs, combined with observed travel time data, we find that contrary to their vision, TNCs are the biggest contributor to growing traffic congestion in San Francisco. Between 2010 and 2016, weekday vehicle hours of delay increased by 62% compared to 22% in a counterfactual 2016 scenario without TNCs. The findings ...


Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman Apr 2019

Using A Balloon-Launched Unmanned Glider To Validate Real-Time Wrf Modeling, Travis J. Schuyler, S. M. Iman Gohari, Gary Pundsack, Donald Berchoff, Marcelo I. Guzman

Chemistry Faculty Publications

The use of small unmanned aerial systems (sUAS) for meteorological measurements has expanded significantly in recent years. SUAS are efficient platforms for collecting data with high resolution in both space and time, providing opportunities for enhanced atmospheric sampling. Furthermore, advances in mesoscale weather research and forecasting (WRF) modeling and graphical processing unit (GPU) computing have enabled high resolution weather modeling. In this manuscript, a balloon-launched unmanned glider, complete with a suite of sensors to measure atmospheric temperature, pressure, and relative humidity, is deployed for validation of real-time weather models. This work demonstrates the usefulness of sUAS for validating and improving ...


Reduction Of Amine Emissions From An Aqueous Amine Carbon Dioxide Capture System Using Charged Colloidal Gas Aphrons, Xiaobing Li, Jesse G. Thompson, Kunlei Liu Apr 2019

Reduction Of Amine Emissions From An Aqueous Amine Carbon Dioxide Capture System Using Charged Colloidal Gas Aphrons, Xiaobing Li, Jesse G. Thompson, Kunlei Liu

Center for Applied Energy Research Faculty Patents

The present invention includes a system and process to reduce amine mist emissions (or MEA) from carbon capture systems using colloidal gas aphrons (CGA), and includes a method for separating and recovering an amine solvent (e.g., in the form of entrained droplets/mist and/or fine aerosol particles) from a carbon dioxide scrubbed flue gas stream exiting a carbon capture system (e.g., oil-fired power plants, coal-fired power plants, and/or natural gas combined cycle plants).


Surface-Controlled Dissolution Rates: A Case Study Of Nanoceria In Carboxylic Acid Solutions, Eric A. Grulke, Matthew J. Beck, Robert A. Yokel, Jason M. Unrine, Uschi M. Graham, Matthew L. Hancock Apr 2019

Surface-Controlled Dissolution Rates: A Case Study Of Nanoceria In Carboxylic Acid Solutions, Eric A. Grulke, Matthew J. Beck, Robert A. Yokel, Jason M. Unrine, Uschi M. Graham, Matthew L. Hancock

Chemical and Materials Engineering Faculty Publications

Nanoparticle dissolution in local milieu can affect their ecotoxicity and therapeutic applications. For example, carboxylic acid release from plant roots can solubilize nanoceria in the rhizosphere, affecting cerium uptake in plants. Nanoparticle dispersions were dialyzed against ten carboxylic acid solutions for up to 30 weeks; the membrane passed cerium-ligand complexes but not nanoceria. Dispersion and solution samples were analyzed for cerium by inductively coupled plasma mass spectrometry (ICP-MS). Particle size and shape distributions were measured by transmission electron microscopy (TEM). Nanoceria dissolved in all carboxylic acid solutions, leading to cascades of progressively smaller nanoparticles and producing soluble products. The dissolution ...


Green Synthesis Nanocomposite Membranes, Dibakar Bhattacharyya, Vasile Smuleac, Rajender S. Varma, Subhas K. Sikdar Apr 2019

Green Synthesis Nanocomposite Membranes, Dibakar Bhattacharyya, Vasile Smuleac, Rajender S. Varma, Subhas K. Sikdar

Chemical and Materials Engineering Faculty Patents

A nanocomposite membrane includes a macroporous polymer membrane having a plurality of pores. A plurality of metal nanoparticles are synthesized and immobilized within those plurality of pores. The nanoparticles are reduced and capped with a green reducing and capping agent such as green tea extract.


Limit Equilibrium Method-Based Shear Strength Prediction For Corroded Reinforced Concrete Beam With Inclined Bars, Yafei Ma, Baoyong Lu, Zhongzhao Guo, Lei Wang, Hailong Chen, Jianren Zhang Mar 2019

Limit Equilibrium Method-Based Shear Strength Prediction For Corroded Reinforced Concrete Beam With Inclined Bars, Yafei Ma, Baoyong Lu, Zhongzhao Guo, Lei Wang, Hailong Chen, Jianren Zhang

Mechanical Engineering Faculty Publications

Shear strength is a widely investigated parameter for reinforced concrete structures. The corrosion of reinforcement results in shear strength reduction. Corrosion has become one of the main deterioration factors in reinforced concrete beam. This paper proposes a shear strength model for beams with inclined bars based on a limit equilibrium method. The proposed model can be applied to both corroded and uncorroded reinforced concrete beams. Besides the tensile strength of longitudinal steel bars, the shear capacity provided by the concrete on the top of the diagonal crack, the tensile force of the shear steel at the diagonal crack, the degradation ...


Session 3b: Pollutant Removal, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Session 3b: Pollutant Removal, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • Investigation of PlarClean and Gamma-Valerolactone as Solvents for Polysulfone Membrane Fabrication
  • Selenium Removal Using Bacteria Entrapped Alginate Gel Beads in a Packed-Bed Reactor
  • Nanotechnology and Membranes: Water detoxification from Lab Scale to Real Site Applications


Session 3a: Drinking Water, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Session 3a: Drinking Water, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • Evaluating Potential Health Threats from Untreated Karst Springs as Community Drinking Water Sources, Monroe County, Kentucky
  • Benefits of Energy Savings Performance Contracting for Water and Wastewater Treatment Facilities
  • Self-Cleaning Nanocomposite Membranes with Phosphorene-Based Pore Fillers for Water Treatment


Poster Session 2, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Poster Session 2, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • 2.1 Climate Change Impacts on Sediment Transport in a Lowland Watershed System: Controlling Processes and Projection
  • 2.2 Assessment of MRSA Presence in Suburban WWTPs Effluent and Receiving Streams in Lexington, Kentucky
  • 2.3 Heavy Metal Capture and Detection Using Colored Synthetic Dithiol
  • 2.4 Quantifying Nutrient Fate and Transport in Karst Agroecosystems of Central Kentucky: Application of High-Resolution Sensors, Numerical Modeling, and Isotope Tracers
  • 2.5 Magnetic Nanocomposite Materials for the Detection and Removal of Halogenated Organic Pollutants in Contaminated Water Sources
  • 2.6 Measuring and Modeling Morphologic Processes in Karst to Sustain Water Resources in the Future ...


Session 2a: Ecology, Biology, And Climate, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Session 2a: Ecology, Biology, And Climate, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • Ecological Monitoring of WRP Easements in Western Kentucky
  • Discussion of Factors Influencing Ecosystem Productivity in the Greenup Pool of the Ohio River
  • Biotic Interactions Between a Bloom-Forming Cyanobacteria and a Planktonic Protist: Implications for Toxin Production
  • The Use of Multiple Large and Detailed Databases to Evaluate the Impacts of Climate Change on Water Resources in the Ohio River Basin
  • Evaluating and Addressing Climate Awareness and Water in Kentucky


Session 2b: Groundwater And Karst, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Session 2b: Groundwater And Karst, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • Incorporating Machine Learning with LiDAR for Delineating Sinkholes
  • Advances in Urban Karst Hydrological and Contaminant Monitoring Techniques for Real-Time and High-Resolution Applications
  • Finding the Edge: How Can We Apply Edge of Field Monitoring to Karst?
  • An Urban Karst Groundwater Evaluation and Monitoring Toolbox
  • Center-Pivot Irrigation in Western Kentucky: Adding Context to the Discussion


Session 1a: Nutrients And Sediment, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Session 1a: Nutrients And Sediment, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • Nutrient Concentrations, Loads, and Yields at Ambient Water Quality Monitoring Stations
  • Advancement in Watershed and Sediment Transport Modeling Using Dynamic Lateral, Longitudinal, and Vertical Sediment (Dis)connectivity Prediction
  • Canine Nutrient Contributions to the Urban Environment
  • Continuous Nutrient and Turbidity Sensors Reveal the Response of Watershed Sources Connected During Storm Events


Session 1b: Ecological Restoration, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Session 1b: Ecological Restoration, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • The Restoration of Cane Run Creek through Lexington’s Coldstream Park and UK’s Coldstream Research Campus
  • Using Multiple Methods for Better Stream Restoration: Including 2-Dimensional Modeling
  • An Ongoing Success Story: What Data, Persistence, and Patience has Enabled in the Hanging Fork Watershed
  • Reclaiming Mill Creek: A Case Study in Urban Stream Restoration


Poster Session 1, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Poster Session 1, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

  • 1.1 Evaluating Soil Characteristics in Rural and Urban Areas
  • 1.2 Use of eDNA in Detection of Multiple Salamander Species in Eastern Kentucky Streams
  • 1.3 Evaluation of biomass and filtration method on eDNA detection of fantail darters (Etheostoma flabellare)
  • 1.4 The Impact of Agricultural Development on Nutrient Contamination Hotspots Within a Small, Intermittent Watershed at EKU’s Meadowbrook Farm, Madison County, Kentucky
  • 1.5 How Does Drought Length Impact the Runoff and Nutrient Storm Response in an Agricultural, Intermittent Catchment in Central Kentucky?
  • 1.6 Analyzing Sanitary Sewer Overflow Sensitivity to Storm Characteristics
  • 1.7 Evaluating Soil ...


Plenary Session, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Plenary Session, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

No abstract provided.


Proceedings Of 2019 Kentucky Water Resources Annual Symposium, Kentucky Water Resources Research Institute, University Of Kentucky Mar 2019

Proceedings Of 2019 Kentucky Water Resources Annual Symposium, Kentucky Water Resources Research Institute, University Of Kentucky

Kentucky Water Resources Annual Symposium

This symposium was planned and conducted as a part of the state water resources research institute annual program that is supported by Grant/Cooperative Agreement Number G16AP00055 from the United States Geological Survey. The contents of this proceedings document and the views and conclusions presented at the symposium are solely the responsibility of the individual authors and presenters and do not necessarily represent the official views of the USGS or of the symposium organizers and sponsors. This publication is produced with the understanding that the United States Government is authorized to reproduce and distribute reprints for government purposes. Mention of ...