Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Civil and Environmental Engineering (143)
- Electrical and Computer Engineering (116)
- Biomedical Engineering and Bioengineering (110)
- Materials Science and Engineering (96)
- Mechanical Engineering (95)
-
- Civil Engineering (81)
- Operations Research, Systems Engineering and Industrial Engineering (81)
- Chemical Engineering (71)
- Industrial Engineering (51)
- Physical Sciences and Mathematics (43)
- Computer Engineering (38)
- Environmental Engineering (37)
- Engineering Science and Materials (36)
- Automotive Engineering (30)
- Engineering Mechanics (30)
- Power and Energy (17)
- Polymer Science (15)
- Polymer and Organic Materials (15)
- Controls and Control Theory (12)
- Nanoscience and Nanotechnology (12)
- Physics (12)
- Biomaterials (11)
- Molecular, Cellular, and Tissue Engineering (10)
- Operational Research (10)
- Semiconductor and Optical Materials (10)
- Transportation Engineering (10)
- Acoustics, Dynamics, and Controls (9)
- Applied Mechanics (9)
- Environmental Sciences (9)
- Keyword
-
- Optimization (15)
- Simulation (14)
- Polymer (13)
- Tissue engineering (8)
- Modeling (7)
-
- Sustainability (7)
- Uncertainty (7)
- Additive Manufacturing (6)
- Biomaterials (6)
- Machine Learning (6)
- Machine learning (6)
- Tissue Engineering (6)
- Additive manufacturing (5)
- Deep Learning (5)
- Elastin (5)
- Glass (5)
- Lignin (5)
- Nanoparticle (5)
- Sensor (5)
- Automotive (4)
- Click chemistry (4)
- Concrete (4)
- Deep learning (4)
- Finite Element Analysis (4)
- Hydrogel (4)
- Kinetics (4)
- Metamaterials (4)
- Molecular dynamics (4)
- Numerical modeling (4)
- Resilience (4)
Articles 751 - 780 of 781
Full-Text Articles in Engineering
Evaluating The Impacts Of Accelerated Incident Clearance Tools And Strategies By Harnessing The Power Of Microscopic Traffic Simulation , Ryan Fries
All Dissertations
Traffic incidents cause Americans delay, waste fuel, cause injuries, and create toxic emissions. Transportation professionals have implemented a variety of tools to manage these impacts and researchers have studied their effectiveness, illustrating a wide range between different tools and locations. To improve this state of knowledge, this dissertation sought to 1) identify prominent and effective incident management strategies, 2) model six selected incident management strategies within five highway corridors in South Carolina, and 3) apply benefit-cost analysis to evaluate the impact of various combinations of these strategies.
To meet these objectives, the author evaluated published literature of the selected strategies, …
Development Of Prediction Models To Measure Vendor Performance In Surveillance And Auditing Of Aircraft Maintenance, Nikhil Iyengar
Development Of Prediction Models To Measure Vendor Performance In Surveillance And Auditing Of Aircraft Maintenance, Nikhil Iyengar
All Dissertations
Elimination of aviation accidents is one of the primary goals of the Federal Aviation Administration (FAA) and the airline industry. A leading cause of aviation accidents is lack of oversight of various organizational issues, in particular, the organization's maintenance operation performance. The technologies used in the industry generate multiple risks, mostly from three domains: systems, hardware and people. Maintenance performance analyses identify the inherent risk in distributed, large-scale systems. Analysis of existing aviation maintenance data is a crucial step in meeting the aviation industry's need to improve aviation safety. Presently, we lack suitable tools to analyze large bodies of maintenance …
Kinetics Of Surface-Initiated Photoiniferter-Mediated Photopolymerization And Synthesis Of Stimuli-Responsive Polymer Brushes, Santosh Rahane
Kinetics Of Surface-Initiated Photoiniferter-Mediated Photopolymerization And Synthesis Of Stimuli-Responsive Polymer Brushes, Santosh Rahane
All Dissertations
The focus of this research is to understand the kinetic and mechanistic aspects of surface-initiated photoiniferter-mediated photopolymerization (SI-PMP) and exploit the robustness of SI-PMP to synthesize stimuli-responsive polymer brushes. The 'living' characteristics of dithiocarbamate-based photoiniferter-mediated photopolymerization are well documented. However, in this dissertation I show that the growth of poly(methyl methacrylate) (PMMA) brushes by SI-PMP is nonlinear, suggesting loss of radicals during SI-PMP and, in turn, non-living characteristics. Results from kinetic models in conjunction with experimental results suggest that irreversible bimolecular termination reactions are a primary culprit for the loss of radicals during SI-PMP. To overcome this problem of irreversible …
Development And In Vitro Examination Of Materials For Osseointegration, Sahil Jalota
Development And In Vitro Examination Of Materials For Osseointegration, Sahil Jalota
All Dissertations
Bone is a connective tissue with nanosized particles of carbonated apatitic calcium phosphate dispersed in a hydrated collagen matrix. With the ageing of the baby boomer population, an increasing number of people sustain bone fractures and defects. Hence, efforts are underway to develop materials to hasten the healing and repairing of such defects. These materials are termed as artificial bone substitutes.
This study represents innovative techniques for development of bone implant materials and improving the existing substitute materials. Emphasis was on three different kinds of materials: Metals (titanium and alloys), Ceramics (calcium phosphates), and Polymers (collagen). The bioactivity of titanium …
Low-Complexity Iterative Detection Techniques For Slow-Frequency-Hop Spread-Spectrum Communications With Reed-Solomon Coding., Harish Ramchandran
Low-Complexity Iterative Detection Techniques For Slow-Frequency-Hop Spread-Spectrum Communications With Reed-Solomon Coding., Harish Ramchandran
All Dissertations
Slow-frequency-hop (SFH) spread-spectrum communications provide a high level of robustness in packet-radio networks for both military and commercial applications. The use of a Reed-Solomon (R-S) code has proven to be a good choice for use in a SFH system for countering the critical channel impairments of partial-band fading and partial-band interference. In particular, it is effective when reliability information of dwell intervals and individual code symbols can be obtained and errors-and-erasures decoding (EE) can be employed at the receiver.
In this dissertation, we consider high-data-rate SFH communications for which the channel in each frequency slot is frequency selective, manifesting itself …
Models Of Semi-Systematic Visual Search, Sourav Das
Models Of Semi-Systematic Visual Search, Sourav Das
All Dissertations
Visual search is an important aspect of many examination and monitoring tasks. As a result, visual search performance has been the topic of many empirical investigations. These investigations have reported that individual search performance depends on subject factors such as search behavior, which has motivated the development of models of visual search that incorporate this behavior. Search behavior ranges from random to strictly systematic; variation in behavior is commonly assumed to be caused by differences in memory retrieval and search strategy. Accordingly, a mathematical model of semi-systematic search is proposed here that can account for both memory retrieval and other …
Using Cross-Sectioned Multilayer Polymer Film And Surface Modification To Form Chemically Patterned Substrates , Chun Zhang
Using Cross-Sectioned Multilayer Polymer Film And Surface Modification To Form Chemically Patterned Substrates , Chun Zhang
All Dissertations
Highly layered structures are important to micro- and nanofabrication technologies for understanding and controlling surface structures through manipulation of chemical and physical interactions. The objective of this work was to develop a new approach to create micro- and nanopatterned surfaces using multilayer polymer films of commercially available and inexpensive polymers instead of inorganic substrates. As an example, linear low density polyethylene (LLDPE) and ethylene-co-acrylic acid copolymer (EAA) were used as alternating inert and reactive polymers, respectively. Thin cross-sections of the multilayer molded sheets were prepared by ultra-microtoming.
As a precursor to the multilayer work, surface modification of EAA was conducted …
Wall And Ground Movements In A Braced Excavation In Clays And Serviceability Reliability Of Adjacent Buildings, Cheng Liang Hsiao
Wall And Ground Movements In A Braced Excavation In Clays And Serviceability Reliability Of Adjacent Buildings, Cheng Liang Hsiao
All Dissertations
The goal of this dissertation research is to establish an improved procedure for evaluating the excavation-induced ground settlement and building serviceability. This research covers several closely related topics. Firstly, a simplified small strain soil model developed by Hsieh et al. (2003), called the Modified Pseudo Plasticity (MPP) model, is evaluated for its capability and performance in the prediction of the excavation-induced ground deformation behavior using Finite Element Method (FEM). Secondly, for the development of the envisioned empirical models for estimating the excavation-induced wall and ground responses, a database of excavation case histories are compiled. To complement the database of excavation …
Analytical And Intelligent Techniques For Dynamically Secure Dispatches, Aftab Alam
Analytical And Intelligent Techniques For Dynamically Secure Dispatches, Aftab Alam
All Dissertations
The NERC August 14th Blackout report brought out by the task force cited 'failure to ensure operation within secure limits' as one of the main reasons. Many of the numerous recommendations focused on the need for better real-time tools for operators and reliability coordinators. In the absence of such tools the operators are limited to operating in conservative secure operating regions established using offline studies. At the same time, with the fast inception of deregulation, the need to ensure a reliable and secure power system has become all the more vital. The success of a competitive market is dependent upon …
Information Flow To Support Front End Planning, Ryan George
Information Flow To Support Front End Planning, Ryan George
All Dissertations
Previous research has demonstrated the value of front end planning as it impacts project performance. This dissertation summarizes the findings of a research project which examined ways to improve information flow through the front end planning process. The front end planning process was carefully diagrammed as consisting of 33 distinct information flow activities, each with its own information flow entities and interactions. Fifty-one questionnaire survey forms were analyzed to obtain data for the 33 information flow activities that included activity duration, resources expended, and other supplemental insights such as the extent of information availability. The 51 projects were then grouped …
Domination And Decomposition In Multiobjective Programming, Alexander Engau
Domination And Decomposition In Multiobjective Programming, Alexander Engau
All Dissertations
During the last few decades, multiobjective programming has received much attention for both its numerous theoretical advances as well as its continued success in modeling and solving real-life decision problems in business and engineering. In extension of the traditionally adopted concept of Pareto optimality, this research investigates the more general notion of domination and establishes various theoretical results that lead to new optimization methods and support decision making.
After a preparatory discussion of some preliminaries and a review of the relevant literature, several new findings are presented that characterize the nondominated set of a general vector optimization problem for which …
Dynamic Measurements Of Lubrication Film Thickness Of Uhmwpe Contacts For Total Joint Replacements, Andrew Clark
Dynamic Measurements Of Lubrication Film Thickness Of Uhmwpe Contacts For Total Joint Replacements, Andrew Clark
All Dissertations
A new contact sensing technology previously developed in the Biotribology Laboratory at Clemson University was further studied, evaluated, and characterized to extend its use to the measurement of lubricating film thickness. First, the laboratory's force-controlled knee joint simulator was used while dynamic contact pressure measurements under both dry and lubricated conditions were made using the sensor technology employed in two different artificial knee implant geometries. Each implant was machined by the manufacturer from custom blocks of ultra high molecular weight polyethylene (UHMWPE) containing a grid of discrete sensing regions. The difference between the dry and lubricated contact areas measured at …
Elevated Neutral-To-Earth Voltage In Distribution Systems Including Harmonics, Jian Jiang
Elevated Neutral-To-Earth Voltage In Distribution Systems Including Harmonics, Jian Jiang
All Dissertations
The elevated neutral-to-earth voltage (NEV), and the related phenomenon called stray voltage, is analyzed in multigrounded distribution systems. Elevated NEV is typically caused by fundamental frequency currents returning to the source via the neutral conductor and earth. However, harmonic distortion is also found to contribute to elevated NEV. A multiphase harmonic load flow algorithm is developed to examine the effects of various factors on the NEV, including unsymmetrical system configuration, load unbalance and harmonic injection. To fulfill this objective, the system modeling is adapted to include the neutral conductor into the component equivalent circuit. The overhead transmission line is remodeled …
Development Of Fatigue Predictive Models Of Rubberized Asphalt Concrete (Rac) Containing Reclaimed Asphalt Pavement (Rap) Mixtures, Feipeng Xiao
All Dissertations
In recent years, some by-products such as crumb rubber has been used to save money, protect the environment, and extend the life of asphalt pavements. In addition, the utilization of reclaimed asphalt pavement (RAP) is an acceptable practice in many states around the United States and many countries all over the world. However, the use of RAP containing crumb rubber has not been investigated in great detail, so it is essential to explore whether these materials have a positive effect on the fatigue life of asphalt pavement. In general, previous experience shows that the use of RAP has proven to …
A Multidimensional Scaling And Participatory Design Approach To Classify Open Ended Aircraft Maintenance Data, Kunal Kapoor
A Multidimensional Scaling And Participatory Design Approach To Classify Open Ended Aircraft Maintenance Data, Kunal Kapoor
All Dissertations
The quality assurance data to be analyzed by the web-based surveillance and auditing tool (WebSAT) is both qualitative and quantitative. The forced responses to checklist questions provide a definitive outcome identifying the effectiveness of the four quality assurance work functions. On the other hand, open-ended responses, the second type of response for capturing maintenance errors, are qualitative in nature since they reflect what the auditors and quality assurance representatives observe during their interactions at vendor locations. This research proposes to apply the statistical technique of multidimensional scaling (MDS) and the User centered Design (UCD) method of Participatory Design (PD) to …
Investigation Of Flow And Microstructure In Rheometric And Processing Flow Conditions For Liquid Crystalline Pitch, Santanu Kundu
Investigation Of Flow And Microstructure In Rheometric And Processing Flow Conditions For Liquid Crystalline Pitch, Santanu Kundu
All Dissertations
A fundamental understanding of flow and its influence on the microstructure is required to obtain carbon materials with desired properties. The objective of this research was to investigate the flow and microstructural behavior of a synthetic mesophase pitch (AR-HP) in rheometric and processing flow conditions. In addition, simulation studies were performed to establish a frame work for modeling the flow behavior of this complex material in different flow situations.
The steady-shear viscosities obtained from a cone-plate rheometer during increasing rate-sweep experiments exhibited a shear-thinning region (Region I) with a slope of about -0.2 and a plateau (Region II) region. The …
Modeling Of The Transient Behavior Of Heat Pipes With Room-Temperature Working Fluids, Pascal Brocheny
Modeling Of The Transient Behavior Of Heat Pipes With Room-Temperature Working Fluids, Pascal Brocheny
All Dissertations
The heat pipe is a capillary-driven and two-phase flow device, capable of transporting and converting large amounts of energy with minimal losses. As a means of thermal management, uses of heat pipe technology not only include thermal control of satellites and spacecrafts in aerospace applications, but also the cooling of electronic components for ground applications. Recently, there has been a flourishing interest in exploring the use of heat pipe technology in the automotive field. However, in many thermal control applications, heat pipes using room-temperature working fluids, such as water or ammonia, with operating temperatures between 200 K (-73ºC) and 550 …
Use Of Personas For User Interface Design: Results Of Field And Experimental Studies , Pallavi Dharwada
Use Of Personas For User Interface Design: Results Of Field And Experimental Studies , Pallavi Dharwada
All Dissertations
Persona is a fictitious user serving as a role model for designers, helping them make difficult decisions from the users' perspective during the interface design process. This concept, which was introduced by Alan Cooper in 1999, has been found to be a powerful tool for engaging the designers with the users. Although personas do not replace the rich data acquired through user testing, they enhance the interface development process by focusing the designers' attention on the target user until the interface qualifies for testing. Recognizing the benefits of persona, many companies, including the Fortune 500 have embraced this concept as …
Tribological Systems For The Evaluation Of Supercritical Carbon Dioxide Sterilized Ultra-High Molecular Weight Polyethylene, John Desjardins
Tribological Systems For The Evaluation Of Supercritical Carbon Dioxide Sterilized Ultra-High Molecular Weight Polyethylene, John Desjardins
All Dissertations
Polymeric biomaterials are especially susceptible to changes in mechanical and surface material properties as a result of sterilization processes that involve heat, moisture and/or irradiation. This is problematic for polymeric materials used in total joint replacement bearings, as these constructs must retain their superior mechanical and tribological properties over their expected 10-20 years of implantation. A younger more active patient population has now exacerbated this longevity issue with service lifetimes of 20+ years now being expected. Supercritical phase carbon dioxide (SC-CO2) is an industrial solvent that has shown great promise as a sterilizing agent in the food industry. Recently, SC-CO2 …
A Robust Conjugate Heat Transfer Methodology With Novel Turbulence Modeling Applied To Internally-Cooled Gas Turbine Airfoils, William York
A Robust Conjugate Heat Transfer Methodology With Novel Turbulence Modeling Applied To Internally-Cooled Gas Turbine Airfoils, William York
All Dissertations
Computational fluid dynamics and heat transfer (CFD) has become a viable, physics-based analysis tool for complex flow and/or heat transfer problems in recent years due, in large part, to rapid advances in computing power. CFD based on the Reynolds-averaged Navier-Stokes (RANS) equations is starting to enter the mainstream design environment in certain industries where rapid and reliable predictive capability is necessary. One such application is the gas turbine industry, where thermal management of airfoils at extremely high temperatures is one of the most critical components in engine design for reliability. The problem is complicated by the need for advanced airfoil …
Modeling Long-Term Plutonium Transport In The Savannah River Site Vadose Zone, Deniz Demirkanli
Modeling Long-Term Plutonium Transport In The Savannah River Site Vadose Zone, Deniz Demirkanli
All Dissertations
Improved understanding of flow and radionuclide transport in vadose zone sediments is fundamental to future planning involving radioactive materials. Long-term experiments were conducted at the Savannah River Site (SRS), where a series of lysimeters containing sources of different Pu oxidation states were placed in the shallow subsurface and exposed to the environment for 2 to 11 years. After the experiments, Pu activity concentrations were measured along vertical cores. The distributions were anomalous in nature, with irregular downward migration and unexpected upward migration. Previous studies suggested that surface-mediated, oxidation/reduction (redox) reactions may be responsible for the anomalies. This hypothesis is tested …
Stabilization Of Vascular Elastin By Treatment With Tannins, Jason Isenburg
Stabilization Of Vascular Elastin By Treatment With Tannins, Jason Isenburg
All Dissertations
Elastin is an important component of the extracellular matrix that endows cardiovascular tissue with the ability to extend and recoil repetitively. It has been shown that elastin may be vulnerable to enzymatic degradation and calcification in certain pathological cases. As a result, elastin degeneration may be associated with the failure of tissue-derived cardiovascular devices, such as bioprosthetic heart valves, as well as the development and progression of aortic aneurysms, a disease associated with progressive connective tissue degeneration of the arterial wall. Therefore, an elastin stabilizing agent may be beneficial for both applications. As such, our objectives for elastin stabilization are …
Channel-Access And Routing Protocols For Wireless Ad Hoc Networks With Directional Antennas, Arvind Swaminathan
Channel-Access And Routing Protocols For Wireless Ad Hoc Networks With Directional Antennas, Arvind Swaminathan
All Dissertations
Medium-access control (MAC) and multiple-hop routing protocols are presented that exploit the presence of directional antennas at nodes in a wireless ad hoc network. The protocols are designed for heterogeneous networks in which an arbitrary subset use directional antennas. It is shown that the new protocols improvement the network`s performance substantially in a wide range of scenarios.
A new MAC protocol is presented that employs the RTS/CTS mechanism. It accounts for the constraints imposed by a directional antenna system, and it is designed to exploit the capabilities of a directional antenna. It is shown that the receiver blocking problem is …
Investigation Of The Effects Of Subgrid-Scale Turbulence On Resolvable-Scale Statistics, Qinglin Chen
Investigation Of The Effects Of Subgrid-Scale Turbulence On Resolvable-Scale Statistics, Qinglin Chen
All Dissertations
The effects of the subgrid-scale (SGS) turbulence on the resolvable-scale statistics and the effects of SGS models on large-eddy simulation (LES) are studied. It is shown that the SGS turbulence evolves the resolvable-scale joint probability density function (JPDF) through the conditional means of the SGS stress, the SGS scalar flux, and their production rate, which must be reproduced by the SGS model for LES to predict correctly the one-point resolvable-scale statistics, a primary goal of LES. This necessary condition is used as the basis for studying SGS physics and for testing SGS models. Theoretical predictions, measurements data obtained in a …
Investigation Into Compatibility Between Repair Material And Substrate Concrete Using Experimental And Finite Element Method, Rashmi Pattnaik
Investigation Into Compatibility Between Repair Material And Substrate Concrete Using Experimental And Finite Element Method, Rashmi Pattnaik
All Dissertations
The failure of concrete repairs is mainly due to improper selection of repair material based on individual repair material properties, without investigating the compatibility between repair material and substrate concrete. In this dissertation the compatibility between eight repair materials and substrate concrete was investigated in three stages. First, individual properties of the repair materials such as setting time, flow, compressive strength, flexural strength, split tensile strength, bond strength, drying shrinkage, freeze-thaw resistance, and permeability, were determined using standard ASTM test procedures. Second, the compatibility was investigated using a composite beam under third point loading. Third, the correlation of repair material …
Modeling And Simulation Of Friction-Limited Continuously Variable Transmissions, Nilabh Srivastava
Modeling And Simulation Of Friction-Limited Continuously Variable Transmissions, Nilabh Srivastava
All Dissertations
Over the last few decades, a lot of research effort has increasingly been directed towards developing vehicle transmissions that accomplish the government imperatives of increased vehicle efficiency and lower exhaust (greenhouse gaseous) emissions. These exhaust emissions can be regulated or lowered by increasing the fuel economy of a vehicle, and CVTs (continuously variable transmissions), indubitably, play a crucial role in this plan to improve the fuel economy. A continuously variable transmission is an emerging automotive transmission technology that offers a continuum of gear ratios between desired limits. A CVT offers numerous advantages over the conventional multi-step gear transmissions such as …
Shear-Wave Velocity Model Of Near-Surface Sediments, Site Response, And Building Damage: 1886 Charleston, South Carolina Earthquake, Cedric Fairbanks
Shear-Wave Velocity Model Of Near-Surface Sediments, Site Response, And Building Damage: 1886 Charleston, South Carolina Earthquake, Cedric Fairbanks
All Dissertations
An updated small-strain shear wave velocity (Vs) model of near-surface sediments is constructed using measurements from over 90 investigation sites in the greater Charleston area. It is constructed by separating the Vs measurements into six major geologic units. The six units are: 1) man-made fills, 2) Holocene and late Pleistocene deposits, 3) the Wando Formation, 4) the Ten Mile Hill beds, 5) the Penholoway Formation and the Daniel Island beds, and 6) Tertiary deposits. Median Vs values for these units in the top 25 m are 145 m/s, 111 m/s, 189 m/s, 176 m/s, 285 m/s and 399 m/s, respectively. …
Controlling Steam Flood Migration With Air Injection Wells, Rex Hodges
Controlling Steam Flood Migration With Air Injection Wells, Rex Hodges
All Dissertations
Steam flooding is an aggressive remediation technology for removing volatile organic chemical (VOC) sources that slowly dissolve into passing groundwater. Plume concentrations can be reduced, accelerating cleanup, and decreasing plume management costs. Steam injected in wells surrounding the source spreads outward and develops into a front that drives contamination to a system of groundwater pumping wells in the saturated zone and soil vapor extraction wells in the vadose zone. The process can be modeled with the non-isothermal multi-phase flow simulator T2VOC to include operation designs and factors at individual sites.
A pilot field-scale test at the Savannah River Site (SRS) …
Theoretical And Empirical Investigation Into Polymer Blend Morphology In Fiber Spinning, Ajay D. Padsalgikar
Theoretical And Empirical Investigation Into Polymer Blend Morphology In Fiber Spinning, Ajay D. Padsalgikar
All Dissertations
A promising way of developing new fiber forming materials is by utilization of polymer blends. The morphology of polymer blends has a significant effect on the properties of the resultant fiber. Morphological studies have shown that immiscible additives remain dispersed in the matrix as suspended droplets and that the droplets are elongated into fibrils under the action of shear or extensional forces during processing. The deformability of the dispersed phase is a controlling factor in deciding the resultant morphology and thereby the fiber properties. We report the results of a study of droplet deformation in uniaxial elongational flow under non …
Modeling Of Algal Productivity And Diel Oxygen Profiles In The Partitioned Aquaculture System, Caye M. Drapcho
Modeling Of Algal Productivity And Diel Oxygen Profiles In The Partitioned Aquaculture System, Caye M. Drapcho
All Dissertations
Fish production in pond culture systems is often limited by the dissolved oxygen (DO) concentration. Algal biomass and productivity, which greatly impact the DO concentration, are difficult to control in traditional pond systems. The Partitioned Aquaculture System (PAS) was designed to increase fish production by managing algal productivity and DO through control of algal cell retention time, water depth, and mixing. The objectives of this study were 1) to determine impact of culture conditions on algal productivity, 2) develop a model of algal productivity and diel DO levels, and 3) to predict the maximum fish production attainable with the PAS. …