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Investigation Of Emission Characteristics During Low Temperature Combustion Using Multivariate Adaptive Regression Splines, Mario Velardi
Investigation Of Emission Characteristics During Low Temperature Combustion Using Multivariate Adaptive Regression Splines, Mario Velardi
Graduate Theses, Dissertations, and Problem Reports
Exhaust emissions from diesel engines operating in a low temperature combustion (LTC) regime are significantly affected by fuel composition and injection strategy. The starting point of this study is a collection of data correlating injection system parameters, and fuel characteristics, to response parameters such as engine-out emissions (oxides of nitrogen (NOx), total particulate matter (TPM), carbon monoxide (CO), hydrocarbons (HC)) and brake thermal efficiency (BTE).;The purpose of this work is to develop a statistical analysis tool to assist the emission analyst in modeling problems in which a response of interest is influenced by several variables and the objective is to …
Investigation Of Pm Formation And Evolution In Plumes Emitted By Heavy-Duty Diesel Vehicles: Wind Tunnel Study, Daniele Littera
Investigation Of Pm Formation And Evolution In Plumes Emitted By Heavy-Duty Diesel Vehicles: Wind Tunnel Study, Daniele Littera
Graduate Theses, Dissertations, and Problem Reports
Stringent emission regulations have forced drastic technological improvements in diesel aftertreatment systems, particularly in reducing Particulate Matter (PM) emissions. Studies that have led to these technological advancements were made in controlled laboratory environments and are not representative of real-world emissions from these engines or vehicles. In addition, formation and evolution of PM from these engines are extremely sensitive to overall changes in the dilution process. In light of this, the study of the exhaust plume of a heavy-duty diesel vehicle operated inside a subsonic environmental wind tunnel can give us an idea of the dilution process and the representative emissions …
Stable And Fair Congestion Control Mechanisms For Cooperative Vehicle Safety In Vehicular Networks, Neda Nasiriani
Stable And Fair Congestion Control Mechanisms For Cooperative Vehicle Safety In Vehicular Networks, Neda Nasiriani
Graduate Theses, Dissertations, and Problem Reports
Cooperative vehicle safety (CVS) systems operate based on broadcast of vehicle position and safety information to neighboring cars. The communication medium of CVS is a Dedicated Short Range Communication (DSRC) wireless channel. One of the main challenges in large scale deployment of CVS systems is the issue of scalability. To address the scalability problem, several congestion control methods have been proposed and are currently under field study. These mechanisms adapt transmission rate and power, based on network measures such as: Channel Busy Ratio (CBR), packet reception rate and vehicles tracking error. Channel Busy Ratio (CBR) is defined as the ratio …
Analyzing The Impact Of Wireless Multi-Hop Networking On Vehicular Safety, Rudhir Upretee
Analyzing The Impact Of Wireless Multi-Hop Networking On Vehicular Safety, Rudhir Upretee
Graduate Theses, Dissertations, and Problem Reports
One of the core challenges of Intelligent Transportation System is the dissemination of timely and accurate vehicle information (e.g. speed, position) to geographically large distances without compromising data supply rates from immediate neighbors. This feature is critical for the design of vehicle safety and navigation applications. Single hop broadcasting is often inadequate to ensure vehicle safety when the platoon size is arbitrarily large due to its upper bound on rate and range of wireless message transmission. Existing wireless multi-hop protocols do not ensure reliable message delivery while avoiding network congestion in the shared channel. In this thesis, we make two …
Investigation Of The Dual-Fuel Conversion Of A Direct Injection Diesel Engine, John S. Smallwood
Investigation Of The Dual-Fuel Conversion Of A Direct Injection Diesel Engine, John S. Smallwood
Graduate Theses, Dissertations, and Problem Reports
The transportation sector is the second largest energy-consuming sector in the United States. With heavy-duty vehicles comprising 20% of the sector and petroleum products being used as 93% of the sector's fuel, alternatives fuels continue to be investigated to offset petroleum usage. Natural gas is increasingly being considered as a fuel source due to its abundance in the Marcellus Shale Formation. Compressed natural gas (CNG) is a promising energy source for dual-fuel combustion. It appears to benefit the environment and the economy. With the ability to reduce oxides of nitrogen (NOx) emissions, carbon dioxide (CO2) emissions, and particulate matter (PM) …
Investigation Of Emissions And Fuel Economy For The Integrated Bus Information System, Jun Tu
Investigation Of Emissions And Fuel Economy For The Integrated Bus Information System, Jun Tu
Graduate Theses, Dissertations, and Problem Reports
The primary objective of this study was to investigate emissions and fuel economy, and develop an Integrated Bus Information System (IBIS) for the Federal Transit Administration (FTA). IBIS included the development of transit fleet emissions models to assist transit agencies in evaluating the emissions implications of new transit vehicle procurements. Compared with existing models, the IBIS prediction model was intended to be less complicated but have sufficient accuracy to achieve its task as a vehicle procurement analysis tool.;Fuel economy (FE) and distance specific emissions (g/mile) were evaluated and predicted by the IBIS model, including carbon monoxide (CO), carbon dioxide (CO2), …
Characterization Of The Composition And Toxicity Of Particulate Matter Emissions From Advanced Heavy-Duty Natural Gas Engines, Arvind Thiruvengadam Padmavathy
Characterization Of The Composition And Toxicity Of Particulate Matter Emissions From Advanced Heavy-Duty Natural Gas Engines, Arvind Thiruvengadam Padmavathy
Graduate Theses, Dissertations, and Problem Reports
Heavy-duty natural gas engines compliant with the 2010 EPA emissions standards have a clear advantage over diesel engines in meeting regulations with minimal after-treatment configuration. Heavy-duty natural gas engines are largely promoted as a cleaner burning engine with respect to low PM mass emissions. However, lack of sufficient data and literature on the exhaust emissions from advanced natural gas engines and the potential adverse health effects has raised concern amongst regulatory agencies. Also, the ammonia emissions from three-way catalyst equipped heavy-duty natural gas engines could be a major contributor to the formation of secondary PM in the atmosphere.;This CARB funded …
Development Of A Powertrain Control Algorithm For A Compound-Split Diesel Hybrid-Electric Vehicle, Douglas Alan Ward
Development Of A Powertrain Control Algorithm For A Compound-Split Diesel Hybrid-Electric Vehicle, Douglas Alan Ward
Graduate Theses, Dissertations, and Problem Reports
The goal of this research was to develop a unique powertrain control algorithm for a diesel-powered compound-split hybrid crossover utility vehicle (CUV) and evaluate the fuel consumption and greenhouse gas emissions benefits that can be realized compared to existing non-hybrid, gasoline-powered CUVs. This was achieved through the implementation of engine on/off functionality, regenerative braking, and electric-only drive. The research was conducted in conjunction with the university's participation in EcoCAR: The NeXt Challenge, an inter-collegiate advanced vehicle engineering competition focused on developing alternatively powered vehicles in the interest of providing improved fuel efficiency and reduced tailpipe emissions while maintaining useful vehicle …
Design And Evaluation Of A Marine Scrubber System, Louise S. Ayre
Design And Evaluation Of A Marine Scrubber System, Louise S. Ayre
Graduate Theses, Dissertations, and Problem Reports
Increasingly stringent oxides of nitrogen (NOX) emissions regulations for diesel marine engines are resulting in the development of newer engines with inherent NOX emissions reduction technologies. With typical useful service lives over 20 years, older diesel marine engines are producing disproportionate amounts of NOX emissions when compared with their newer counterparts. The development of retrofit exhaust aftertreatment technologies would therefore aid in reducing the total NOX emissions from these engines.;A marine scrubber system for the reduction of NOX emissions from diesel marine engines was designed, constructed, and evaluated. This work focused on gathering data for the design of a marine …
Concentration And Size Distributions Of Nanoparticle Emissions During Low Temperature Combustion Using Fuels For Advanced Combustion Engines (Face), Peter Bonsack
Graduate Theses, Dissertations, and Problem Reports
Due to tightening emission legislations, both within the US and Europe, including concerns regarding greenhouse gases, next-generation combustion strategies for internal combustion (IC) diesel engines that simultaneously reduce exhaust emissions while improving thermal efficiency have drawn increasing attention during recent years. In-cylinder combustion temperature plays a critical role in the formation of pollutants as well as in thermal efficiency of the propulsion system. One way to minimize both soot and NOx emissions, is to limit the in-cylinder temperature during the combustion process by means of high levels of dilution via exhaust gas recirculation (EGR) combined with flexible fuel injection strategies. …
Vcast: A Distance-Sensitive Scalable Information Dissemination Protocol, Raja Abhinay Moparthi
Vcast: A Distance-Sensitive Scalable Information Dissemination Protocol, Raja Abhinay Moparthi
Graduate Theses, Dissertations, and Problem Reports
The future of intelligent transportation systems lies in dealing with safety and navigation of vehicles. Building a technology that provides the real-time information about the state of other vehicles like its location, speed and direction would help in developing a system that ensures safety along with navigation. However, the network limitations pose difficulty in obtaining the state information over multiple-hops, because of the bandwidth limitations and congestion in the shared wireless channel. Overcoming this challenge would yield an intelligent transportation system which gives information regarding the collisions, lane changes and merges, emergency vehicle approaching alerts, stopped vehicle alerts, etc., over …
Juxtaposition Of In-Use Vehicular Emissions Measurement Equipment, Brock A. Merritt
Juxtaposition Of In-Use Vehicular Emissions Measurement Equipment, Brock A. Merritt
Graduate Theses, Dissertations, and Problem Reports
A study was performed to compare measurement capabilities of two commercially available in-use portable emissions measurement systems, from different generations, in order to determine how or if changes to emissions testing standards have affected in-use equipment. The two in-use systems from different generations were the Sensors, Inc. SEMTECH-D, which would be considered first generation because it was built under the CFR 40, Part 86 standard, and the Horiba, Ltd. OBS-2200, which was considered second generation because it was built under the updated CFR 40, Part 1065 standards. Both systems underwent a series of tests in the laboratory and on-road. For …
Model Based Evaluation Of The Differences Between Full And Partial Flow Particulate Matter Sampling Systems, Nathan Kimble
Model Based Evaluation Of The Differences Between Full And Partial Flow Particulate Matter Sampling Systems, Nathan Kimble
Graduate Theses, Dissertations, and Problem Reports
PM has been shown to be harmful to people, animals, and the environment. For this reason PM is a regulated emission. As federal regulation of particulate matter (PM) becomes tighter, the need to accurately measure it becomes paramount. As the limit decreases, it becomes more difficult to measure PM due to the inaccuracies in the measurement equipment, and the nature of the particles to be lost in the sampling system.;This study investigated the error propagation and particle loss in two common PM mass measurement systems, the full flow sampling system, also called the constant volume sampling (CVS), and the partial …
Study Of Transit Bus Duty Cycle And Its Influence On Fuel Economy And Emissions Of Diesel-Electric Hybrids, Jairo A. Sandoval Leon
Study Of Transit Bus Duty Cycle And Its Influence On Fuel Economy And Emissions Of Diesel-Electric Hybrids, Jairo A. Sandoval Leon
Graduate Theses, Dissertations, and Problem Reports
The Center for Alternative Fuels, Engines, and Emissions (CAFEE) of West Virginia University (WVU) is developing the Integrated Bus Information System (IBIS), an information resource on transit bus emissions for vehicle procurement purposes. IBIS provides the transit bus industry with exhaust emissions information, including an emissions database, and predictive models for fuel economy (F.E.) and emissions. Inputs for the models are in the form of drive cycle metrics, but the knowledge of such metrics is not readily available for transit agencies.;The first part of this dissertation was an effort to close the gap between engineering drive cycle metrics and the …
Enabling Hcci Combustion Of N-Heptane Through Thermo-Chemical Recuperation, Francisco Posada Sanchez
Enabling Hcci Combustion Of N-Heptane Through Thermo-Chemical Recuperation, Francisco Posada Sanchez
Graduate Theses, Dissertations, and Problem Reports
Concerns over air quality, environmental regulatory requirements and the need for reducing fuel consumption on conventional internal combustion engines (ICE) have motivated the development of alternative combustion processes for ICE. One alternative, homogeneous charge compression ignition (HCCI), has shown benefits of high efficiency with low NOx emissions, but suffers load range limitations and control issues. An increase in equivalence ratio at constant speed changes the combustion timing relative to top dead center (TDC), and also increases the pressure rise rate. The opposite occurs if the equivalence ratio is reduced, delaying the combustion timing with respect to TDC and reducing the …
Optimization Of A Heavy-Duty Hybrid Transit Bus Operated Over Transient Cycles, Pingen Chen
Optimization Of A Heavy-Duty Hybrid Transit Bus Operated Over Transient Cycles, Pingen Chen
Graduate Theses, Dissertations, and Problem Reports
This thesis centers on the simulation and optimization of a hybrid transit bus when operated over transient emissions cycles. The simulation was conducted using Powertrain System Analysis Toolkit (PSAT) as a platform by integrating components' data and operation maps of a "pre-transmission" parallel hybrid transit bus. The model was validated against the limited experimental data when operated over the China's Urban Bus (CUB) driving cycle and the Beijing cycle. The validated model was then used to predict the performance and exhaust emissions of this hybrid bus operated over typical U.S. cycles. The potential of a real-time control strategy in improving …
Small Engine Emissions Testing Laboratory Development And Emissions Sampling System Verification, Balaji B. Seward
Small Engine Emissions Testing Laboratory Development And Emissions Sampling System Verification, Balaji B. Seward
Graduate Theses, Dissertations, and Problem Reports
With the recent scrutiny of engine emissions and a focus towards higher fuel efficiencies, there has been an increase in demand for small, efficient engines and small engine emissions testing. Small engines have proven to provide high efficiency performance for systems including refrigeration units, generators, compressors and numerous other off-road applications. In the past, the existing emissions testing facilities at West Virginia University's (WVU) Center for Alternative Fuels, Engines and Emissions (CAFEE) have been focused towards the testing of heavy duty diesel engines.;In order to expand the emissions testing capabilities at CAFEE, a new small engine emissions testing laboratory was …
Optimization Of A Retrofit Urea-Scr System, Clinton R. Bedick
Optimization Of A Retrofit Urea-Scr System, Clinton R. Bedick
Graduate Theses, Dissertations, and Problem Reports
Oxides of nitrogen (NOx) emissions from legacy diesel engines are often many times over currently mandated standards, contributing significantly to degradation of air quality and negative environmental impact. A retrofit urea-SCR (selective catalytic reduction) aftertreatment system offers a viable solution for reducing NOx emissions from older diesel engines. A stand-alone retrofit urea-SCR aftertreatment system was previously developed by West Virignia University (WVU) engineers, implementing a pre-SCR NOx sensor, open-loop feed-forward control, and stoichiometric NOx reduction logic. During experimental testing at WVU, the urea-SCR system demonstrated NOx reductions of 2% to 53%, depending on the test cycle. In order to optimize …
Transient Flow Characteristics Of A High Speed Rotary Valve, Patrick H. Browning
Transient Flow Characteristics Of A High Speed Rotary Valve, Patrick H. Browning
Graduate Theses, Dissertations, and Problem Reports
Pressing economic and environmental concerns related to the performance of fossil fuel burning internal combustion engines have revitalized research in more efficient, cleaner burning combustion methods such as homogeneous charge compression ignition (HCCI). Although many variations of such engines now exist, several limiting factors have restrained the full potential of HCCI. A new method patented by West Virginia University (WVU) called Compression Ignition by Air Injection (CIBAI) may help broaden the range of effective HCCI operation. The CIBAI process is ideally facilitated by operating two synchronized piston-cylinders mounted head-to-head with one of the cylinders filled with a homogeneous mixture of …
Characterization Of Exhaust Emissions From Palm Oil-Based And Soybean Oil-Based Biodiesel Fueled Heavy-Duty Transit Buses, Trampas Jay Efaw
Characterization Of Exhaust Emissions From Palm Oil-Based And Soybean Oil-Based Biodiesel Fueled Heavy-Duty Transit Buses, Trampas Jay Efaw
Graduate Theses, Dissertations, and Problem Reports
Biodiesel blends offer a renewable energy fueling option for compression-ignition internal combustion engines. Typically, biodiesel blended at or less than 20% (B20), by volume, will exhibit substantial reductions in diesel particulate matter (PM), while not significantly impacting oxides of nitrogen (NO X) emissions. Additionally, operation on biodiesel blended at B20 levels or less has not been associated with substantial fuel economy penalties.;A study was conducted, wherein two transit buses were utilized to quantify the emissions and performance effects associated with the use of biodiesel fuels, derived from palm oil and soybean oil. Evaluation of the two fuels was accomplished through …
Design And Testing Of The Wvu Challenge X Competition Hybrid Diesel Electric Vehicle, Howard Andrew Mearns
Design And Testing Of The Wvu Challenge X Competition Hybrid Diesel Electric Vehicle, Howard Andrew Mearns
Graduate Theses, Dissertations, and Problem Reports
The WVU Challenge X Team was tasked with improving the fuel economy of a 2005 Chevrolet Equinox while maintaining the stock performance of the vehicle. A through-the-road-parallel hybrid diesel-electric was implemented to accomplish this goal. The greatest potential for improvement to hybrid electric vehicle technology is in energy storage in terms of cost, size, lifespan, and efficiency. Currently, battery cost is limited by the expense of the base materials. The characteristically low power density of electrochemical energy storage rather than energy density is responsible for the size of current hybrid energy storage systems. A limited lifespan is inherent in electrochemical …
Influence Of Accelerator Pedal Position Control On Heavy Duty Diesel Engine Emissions And Performance, Michael Ursic
Influence Of Accelerator Pedal Position Control On Heavy Duty Diesel Engine Emissions And Performance, Michael Ursic
Graduate Theses, Dissertations, and Problem Reports
Heavy-duty diesel engines (HDDEs) typically burn hydrocarbon fuels and as a result their emissions cause harmful products of combustion to be emitted into the atmosphere. Due to these harmful emissions, the United States Environmental Protection Agency (EPA) has created strict emissions standards for these heavy-duty engine manufacturers to meet. Engine manufacturers strive to meet these stringent standards while maintaining performance requirements set forth by the consumer. The EPA currently mandates laboratory testing of all HDDE families on an engine dynamometer utilizing a standard testing procedure. One standard testing procedure that HDDEs must execute is commonly known as a Federal Testing …
The Effect Of Different Road Load Implementation Strategies On Fuel Economy Of Usps Step Vans, Seiar Ahmad Zia
The Effect Of Different Road Load Implementation Strategies On Fuel Economy Of Usps Step Vans, Seiar Ahmad Zia
Graduate Theses, Dissertations, and Problem Reports
West Virginia University (WVU) is continuously improving and updating their testing quality, procedures and goals. As tests are conducted on the Transportable Heavy Duty Vehicle Emissions Testing Laboratory (THDVETL), real world implementation is crucial in order to compare and contrast vehicles within fleets, use of exhaust aftertreatment devices and hybridized vehicles. WVU implements road loads on the chassis dynamometer using a method described in 40 CFR §86.1229-85. The proposed method requires three variables from the vehicle: maximum height, maximum width and vehicle weight. The issue with this method arises due to the fact that it does not cover a wide …
Fuel Economy And Emissions Benefits From Diesel Fuel Additives, Geoffrey James Newlin
Fuel Economy And Emissions Benefits From Diesel Fuel Additives, Geoffrey James Newlin
Graduate Theses, Dissertations, and Problem Reports
With the spike in fuel costs during 2008, fuel consumption, and methods to reduce it, has come to the forefront of society, and recognition that inexpensive energy sources for mobile transportation may be a thing of the past. Even though fuel costs did significantly decrease by 75% after this spike [1], they will most likely continue to rise. Improvements to mobile transportation and the reduction of greenhouse gas emissions are a major agenda item of the United States and many industrialized nations. New and improved technologies will be developed and employed for future transportation needs of society. However, the existing …
The Effects Of Fuel Additives On Diesel Engine Emissions During Steady State And Transient Operation, John P. Nuszkowski
The Effects Of Fuel Additives On Diesel Engine Emissions During Steady State And Transient Operation, John P. Nuszkowski
Graduate Theses, Dissertations, and Problem Reports
Internal combustion engines have propelled society's transportation and power needs for the last century. However, with the regulatory demand to reduce air pollution, internal combustion engines are a major focus to reduce the emissions from these engines. Compression ignition or diesel engines are a major contributor to NOx and PM pollution. However, the life of these engines is much longer than that of their spark-ignited counterparts, causing the fleet of diesel engines to consist of a significant number of old, higher polluting engines. Fuel additives are one method of reducing emissions and/or enhancing performance in these older diesel engines without …
Efficiency Optimization And Control Of Permanent Magnet Synchronous Brushless Motors In Three-Phase Pulse Width Modulated Voltage Source Inverter Drives, Olusegun Richard Solomon
Efficiency Optimization And Control Of Permanent Magnet Synchronous Brushless Motors In Three-Phase Pulse Width Modulated Voltage Source Inverter Drives, Olusegun Richard Solomon
Graduate Theses, Dissertations, and Problem Reports
In high performance drives where it is desirable to exploit the usefulness of reluctance torque and machine saliency, permanent magnet synchronous brushless motors are machines of choice. However, speed control of these machines especially in the flux weakening region becomes more complex due to the non-linear coupling among the winding currents as well as the nonlinearity present in the torque. While numerous research efforts in the past have considered control and efficiency improvements of induction motors, and synchronous motors with field windings, research efforts in developing an efficiency optimization and control strategy applicable to all salient-type permanent magnet synchronous brushless …
Design And Performance Analysis Of Electric Vehicles Fed By Multiple Fuel Cells, Pardis Khayyer
Design And Performance Analysis Of Electric Vehicles Fed By Multiple Fuel Cells, Pardis Khayyer
Graduate Theses, Dissertations, and Problem Reports
Recent advances in fuel cell developments have introduced them to many applications such as hybrid electric vehicles and heat/power cogenerations. They bring the advantage of clean energy and decrease the dependency on imported oil by providing fuel efficient devices in many applications such as electric vehicles. Conventional designs of hybrid fuel cell vehicles make use of a single fuel cell power source and a storage device to provide the base load and transients in various driving cycles. This thesis proposes a new configuration of multiple fuel cell power sources in hybrid fuel cell vehicles. Fuel cells are downsized in this …
Growth Of Diesel Exhaust Particulate Matter In A Ventilated Mine Tunnel, Glen A. Wilt
Growth Of Diesel Exhaust Particulate Matter In A Ventilated Mine Tunnel, Glen A. Wilt
Graduate Theses, Dissertations, and Problem Reports
The objective of this work was to study the formation and evolutionary characteristics of aerosols, originating from the exhaust plume of a diesel engine operating in a ventilated mine tunnel. To extract these characteristics, precise cross-sectional scalar exhaust maps of CO2, temperature, and aerosol concentration were generated and used to track the time averaged axial development of the plume. These maps were then used to position aerosol size distribution samples within critical regions of the plume. This approach was found to provide an efficient and thorough record of aerosol formation and evolution, as a result of naturally dispersed diesel exhaust …
Quantifying Effects Of Vehicle Weight And Terrain On Emissions, Fuel Economy, And Engine Behavior, Corey M. Strimer
Quantifying Effects Of Vehicle Weight And Terrain On Emissions, Fuel Economy, And Engine Behavior, Corey M. Strimer
Graduate Theses, Dissertations, and Problem Reports
On-board emissions measurement for heavy-duty vehicles has garnered greater significance because 2007 marks the beginning of gaseous emissions monitoring for in-use vehicles in the United States [1]. Emissions compliance must be shown in a "not to exceed" (NTE) zone that emphasizes engine operation at higher power. An over-the-road 1996 Peterbilt tractor was instrumented with the West Virginia University Mobile Emissions Measurement System (MEMS) to determine how often the truck entered the NTE, and the emissions from the vehicle, as it was driven over varying terrain at multiple test weights. Distance-specific NOX emissions increase by approximately X/2% for an X% increase …
Development Of Predictive Nox Model For On -Road Heavy -Duty Diesel Engines, Mohan Krishnamurthy
Development Of Predictive Nox Model For On -Road Heavy -Duty Diesel Engines, Mohan Krishnamurthy
Graduate Theses, Dissertations, and Problem Reports
Emissions models currently employed by EPA and CARB do not account for the variations in engine operation and their effect on emissions. Alternatively, this study, demonstrates the feasibility of using Engine Control Module (ECM) broadcast parameters such as Engine Speed, Engine Torque, Injection Timing, Fueling Rate, Manifold Air Temperature, Manifold Air Pressure, Coolant Temperature and Oil Temperature as inputs to in order to predict engine-out exhaust NO x emissions. These parameters were obtained when the engine operates in the Not-to-Exceed (NTE) zone, (which is defined by 40 CFR §86.1370-2007) for a continuous time period of at least 30s in length.;This …