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2023

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Full-Text Articles in Engineering

Cobalt Oxide Functionalized Ceramic Membrane For 4-Hydroxybenzoic Acid Degradation Via Peroxymonosulfate Activation, Rajan Arjan Kalyan Hirani, Hong Wu, Abdul Hannan Asif, Nasir Rafique, Lei Shi, Shu Zhang, Zhentao Wu, Lai-Chang Zhang, Shaobin Wang, Yu Yin, Martin Saunders, Hongqi Sun Apr 2023

Cobalt Oxide Functionalized Ceramic Membrane For 4-Hydroxybenzoic Acid Degradation Via Peroxymonosulfate Activation, Rajan Arjan Kalyan Hirani, Hong Wu, Abdul Hannan Asif, Nasir Rafique, Lei Shi, Shu Zhang, Zhentao Wu, Lai-Chang Zhang, Shaobin Wang, Yu Yin, Martin Saunders, Hongqi Sun

Research outputs 2022 to 2026

Membrane separation and sulfate radicals-based advanced oxidation processes (SR-AOPs) can be combined as an efficient technique for the elimination of organic pollutants. The immobilization of metal oxide catalysts on ceramic membranes can enrich the membrane separation technology with catalytic oxidation avoiding recovering suspended catalysts. Herein, nanostructured Co3O4 ceramic catalytic membranes with different Co loadings were fabricated via a simple ball-milling and calcination process. Uniform distribution of Co3O4 nanoparticles in the membrane provided sufficient active sites for catalytic oxidation of 4-hydroxybenzoic acid (HBA). Mechanistic studies were conducted to determine the reactive radicals and showed that …


Femtotesla Magnetometry And Nanoscale Imaging With Color Centers In Diamond, Yaser Silani Apr 2023

Femtotesla Magnetometry And Nanoscale Imaging With Color Centers In Diamond, Yaser Silani

Optical Science and Engineering ETDs

Intriguing photophysical properties of color centers in diamond make them ideal candidates for many applications from imaging and sensing to quantum networking. In the first part of this work, we have studied the silicon vacancy (SiV) centers in diamond for nanoscale imaging applications. We showed that these centers are promising fluorophores for Stimulated Emission Depletion (STED) microscopy, owing to their photostable, near-infrared emission and favorable photophysical properties. In the second part, we built a femtotesla Radio-Frequency (RF) magnetometer based on the diamond nitrogen vacancy (NV) centers and magnetic flux concentrators. We used this sensor to remotely detect Nuclear Quadrupole Resonance …


Feasibility Study For A Continuous Mansfield Hollow State Park Multi-Use Path, Owen P. Spangler Apr 2023

Feasibility Study For A Continuous Mansfield Hollow State Park Multi-Use Path, Owen P. Spangler

Honors Scholar Theses

This report aims to design a pedestrian river crossing that connects the north and south ends of Mansfield Hollow State Park, utilizing both a new paved pathway and bridge construction. This report first uses GIS data to complete a feasibility study on pathway routing and cost. A preliminary route was selected based on grading and cost analysis. The requirements for constructing a multi-use pathway in the State of Connecticut were then explored, attempting to find a best-fit pathway alignment to accomplish that goal. Through a lengthy literature review, it was found that the pathway design would have to deviate from …


Experimental And Numerical Studies Of Slurry-Based Coextrusion Deposition Of Continuous Carbon Fiber Micro-Batteries To Additively Manufacture 3d Structural Battery Composites, Aditya R. Thakur, Xiangyang Dong Apr 2023

Experimental And Numerical Studies Of Slurry-Based Coextrusion Deposition Of Continuous Carbon Fiber Micro-Batteries To Additively Manufacture 3d Structural Battery Composites, Aditya R. Thakur, Xiangyang Dong

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Carbon Fiber Structural Battery Composites Have Recently Attracted Growing Interests Due to their Potentials of Simultaneously Carrying Mechanical Loads and Storing Electrical Energy for Lightweight Application. in This Study, We Present a Slurry-Based Coextrusion Deposition Method to Additively Manufacture 3D Structural Battery Composites from Carbon Fiber Micro-Batteries. Cathode Slurry is Coextruded Together with Solid Polymer Electrolyte-Coated Carbon Fibers in a Single Deposition. a Network of Carbon Fiber Micro-Batteries is Achieved within the Fabricated Structural Battery Composites. Electrochemical Tests Show a Stable Charge-Discharge Performance Up to 100 Cycles. the Rheological Behavior of the Cathode Slurry is Found to Govern the Coextrusion …


Utilizing Robust Design To Optimize Composite Bioadhesive For Promoting Dermal Wound Repair, Rattapol Pinnaratip, Zhongtian Zhang, Ariana Smies, Pegah Kord Forooshani, Xiaoqing Tang, Rupak Rajachar, Bruce Lee Apr 2023

Utilizing Robust Design To Optimize Composite Bioadhesive For Promoting Dermal Wound Repair, Rattapol Pinnaratip, Zhongtian Zhang, Ariana Smies, Pegah Kord Forooshani, Xiaoqing Tang, Rupak Rajachar, Bruce Lee

Michigan Tech Publications, Part 1

Catechol-modified bioadhesives generate hydrogen peroxide (H2O2) during the process of curing. A robust design experiment was utilized to tune the H2O2 release profile and adhesive performance of a catechol-modified polyethylene glycol (PEG) containing silica particles (SiP). An L9 orthogonal array was used to determine the relative contributions of four factors (the PEG architecture, PEG concentration, phosphate-buffered saline (PBS) concentration, and SiP concentration) at three factor levels to the performance of the composite adhesive. The PEG architecture and SiP wt% contributed the most to the variation in the results associated with the H2O2 release profile, as both factors affected the crosslinking …


Development Of A Smart Waste Management System For City Application, Lawrence D. Fraction Apr 2023

Development Of A Smart Waste Management System For City Application, Lawrence D. Fraction

Morehead State Theses and Dissertations

A thesis presented to the faculty of the Elmer R. Smith College of Business and Technology Morehead State University in partial fulfillment of the requirements for the Degree Master of Science by Lawrence D. Fraction on April 14, 2023.


Current Prospects And Challenges In Negative-Capacitance Field-Effect Transistors, Md. Sherajul Islam, Abdullah Al Mamun Mazumder, Changjian Zhou, Catherine Stampfl, Jeongwon Park, Cary Y. Yang Apr 2023

Current Prospects And Challenges In Negative-Capacitance Field-Effect Transistors, Md. Sherajul Islam, Abdullah Al Mamun Mazumder, Changjian Zhou, Catherine Stampfl, Jeongwon Park, Cary Y. Yang

Electrical and Computer Engineering

For decades, the fundamental driving force behind energy-efficient and cost-effective electronic components has been the downward scaling of electronic devices. However, due to approaching the fundamental limits of silicon-based complementary metal-oxide-semiconductor (CMOS) devices, various emerging materials and device structures are considered alternative aspirants, such as negative-capacitance field-effect transistors (NCFETs), for their promising advantages in terms of scaling, speed, and power consumption. In this article, we present a brief overview of the progress made on NCFETs, including theoretical and experimental approaches, a current understanding of NCFET device physics, possible physical mechanisms for NC, and future functionalization prospects. In addition, in the …


Effect Of Protective Cladding On The Fire Performance Of Vertically Loaded Cross-Laminated Timber (Clt) Wall Panels, Muhammad Yasir, Andrew Macilwraith, Conan O'Ceallaigh, Kieran Ruane Apr 2023

Effect Of Protective Cladding On The Fire Performance Of Vertically Loaded Cross-Laminated Timber (Clt) Wall Panels, Muhammad Yasir, Andrew Macilwraith, Conan O'Ceallaigh, Kieran Ruane

Publications

Cross-laminated timber (CLT) is a sustainable engineered wood product which is utilised in modern multi-storey timber buildings. The fire behaviour of timber structures is often a concern due to their combustible nature. In this paper, experimental fire testing of CLT panels made of Irish spruce was performed. This series of tests consisted of four vertically loaded CLT wall panels which were tested under Standard fire curves in the Structural Laboratory of Munster Technological University, Cork (MTU). To improve the fire performance of CLT panels, different types of protective claddings were used. The effectiveness of each system of protection has been …


Role Of Ai In Threat Detection And Zero-Day Attacks, Kelly Morgan Apr 2023

Role Of Ai In Threat Detection And Zero-Day Attacks, Kelly Morgan

Cybersecurity Undergraduate Research Showcase

Cybercrime and attack methods have been steadily increasing since the 2019 pandemic. In the years following 2019, the number of victims and attacks per hour rapidly increased as businesses and organizations transitioned to digital environments for business continuity amidst lockdowns. In most scenarios cybercriminals continued to use conventional attack methods and known vulnerabilities that would cause minimal damage to an organization with a robust cyber security posture. However, zero-day exploits have skyrocketed across all industries with an increasingly growing technological landscape encompassing internet of things (IoT), cloud hosting, and more advanced mobile technologies. Reports by Mandiant Threat Intelligence (2022) concluded …


Lack Of Black Female Diversity Within The Cybersecurity Workforce, Eric Preston Apr 2023

Lack Of Black Female Diversity Within The Cybersecurity Workforce, Eric Preston

Cybersecurity Undergraduate Research Showcase

Cybersecurity methods, strategies, and programs for protecting computers and electronic devices have become critically important in all aspects of the technological infrastructure. However, while this is a vastly growing field that has a large workforce, it suffers from a lack of representation, specifically for Black/African American females. This study examines the barriers that prevent Black women from having representation within the cybersecurity workforce and solutions that address them. Some barriers noted include a lack of role models and resources, historical discrimination and systemic barriers, and cultural norms. Additionally, implications created by these barriers include less diversity, a lack of career …


Toward Automatically Composed Fpga-Optimized Robotic Systems Using High-Level Synthesis, Szu-Wei Lin Apr 2023

Toward Automatically Composed Fpga-Optimized Robotic Systems Using High-Level Synthesis, Szu-Wei Lin

Theses and Dissertations

Robotic systems are known to be computationally intensive. To improve performance, developers tend to implement custom robotic algorithms in hardware. However, a full robotic system typically consists of many interconnected algorithmic components that can easily max-out FPGA resources, thus requiring the designer to adjust each algorithm design for each new robotic systems in order to meet specific systems requirements and limited resources. Furthermore, manual development of digital circuitry using a hardware description language (HDL) such as verilog or VHDL, is error-prone, time consuming, and often takes months or years to develop and verify. Recent developments in high-level synthesis (HLS), enable …


Bubble Wand Activity, Admin Stem For Success Apr 2023

Bubble Wand Activity, Admin Stem For Success

STEM for Success Showcase

Students use this activity to practice their engineering skills by building a bubble wand.

Activity Video Link: https://www.youtube.com/watch?time_continue=15&v=wx0-NrAnE6c&feature=emb_logo


Image Analysis Methodology For Evaluating Coating Uniformity Of Drug-Coated Angioplasty Balloons, Allison Dobson Zieschang Apr 2023

Image Analysis Methodology For Evaluating Coating Uniformity Of Drug-Coated Angioplasty Balloons, Allison Dobson Zieschang

LSU Master's Theses

Percutaneous transluminal balloon angioplasty (PTA) is a surgical procedure to treat peripheral artery disease, but restenosis causes suboptimal outcomes in many patients. Drug-coated angioplasty balloons (DCBs) were developed to reduce the risk of restenosis by delivering anti-proliferative drugs to the lesion. The efficacy of DCBs depends on factors like drug loading and drug release rate, both of which are directly impacted by the coating uniformity. This thesis evaluates the uniformity of DBCs using fluorescence microscopy, scanning electron microscopy (SEM), qualitative analysis, and an image processing algorithm. Uniformity was quantified by three measurements: histogram standard deviation, histogram percentage of coverage, and …


Removal Of Radionuclides Using Capacitive Deionization, Yusik Won Apr 2023

Removal Of Radionuclides Using Capacitive Deionization, Yusik Won

LSU Doctoral Dissertations

Severe nuclear accidents, including the Fukushima nuclear power plant accident, can lead to the discharge of large amounts of radionuclides into aquatic environments. Some radionuclides such as 137Cs and 90Sr have long half-lives and can remain in the environment for a long period of time. These radionuclides can be detrimental to humans and the environments because they can cause human and environmental exposure to ionizing radiation and because they can be bioaccumulated and biomagnified. Therefore, in case of a severe accident and a radioactive spill, it is important to quickly clean up and treat radioactively contaminated water to …


Permanent Passive Fire Protection Against Wildland-Urban Interface Fires, Makenzie Wilson Apr 2023

Permanent Passive Fire Protection Against Wildland-Urban Interface Fires, Makenzie Wilson

Theses and Dissertations

The average intensity and frequency of wildland fires have been on the rise over the years, leading to an increase in the risk to homes located in the Wildland-Urban Interface (WUI). Fire suppression is the most used method of wildland fire control, but this suppression can cause wildland fires to become more frequent and devastating. Increased development in the WUI also puts these homes at greater risk. Current methods of passive fire protection are effective, but these methods are expensive, time consuming to set up, and not fully effective. This research proposes a permanent passive fire protection system that is …


Long-Term Modulus Of Microcracked Cement-Treated Base Layers, Patrick Matthew Mcdivitt Apr 2023

Long-Term Modulus Of Microcracked Cement-Treated Base Layers, Patrick Matthew Mcdivitt

Theses and Dissertations

The objective of this research was to measure and analyze the long-term modulus values of cement-treated base (CTB) layers constructed in Utah using microcracking. Because modulus values of pavement layers are among the most influential inputs affecting mechanistic-empirical pavement design, obtaining reasonable estimates of modulus values is critical. Testing was performed with a portable falling-weight deflectometer, also called a lightweight deflectometer, and modulus values were backcalculated with the computer program BAKFAA. Testing occurred at five asphalt pavement sites in northern Utah, where reconstruction with full-depth reclamation and cement stabilization, in the form of cement slurry, was performed approximately 2 to …


Understanding The Behavior Of Upper Subcritical Limit Calculations, Bobbi Riedel Apr 2023

Understanding The Behavior Of Upper Subcritical Limit Calculations, Bobbi Riedel

Nuclear Engineering ETDs

This research consists of two comparison studies: the first study employed standard practices to characterize Upper Subcritical Limit (USL) estimation methods. A series of 33 neutronic systems that used standardized nuclear data and benchmark libraries were studied to compare the Whisper, TSURFER, and USLSTATS methods relative to a stochastic USL. USLs were also estimated for these 20 systems using the Whisper 1.1 code. Sensitivity data files were produced using MCNP6.2 and then used with the ORNL TSURFER and USLSTATS methods to estimate USLs for a cross-method USL comparison. The results show that USLs for each of the loosely coupled system …


Information Horizon Of Solar Active Regions, Jay R. Johnson, Simon Wing, Carson O'Ffill, Bishwa Neupane Apr 2023

Information Horizon Of Solar Active Regions, Jay R. Johnson, Simon Wing, Carson O'Ffill, Bishwa Neupane

Faculty Publications

Information theory is used to characterize the solar active region periodicities and memories from the Carrington map images 1974–2021. The active regions typically evolve and move from one map to the next. In order to track these active region structures in sequences of images, an innovative method based on information theory is developed. Image entropy provides a measure of the organization of structures in the images. The entropy can also be used as a filter to identify structures and partition the active regions, which are then registered for each image. The partitions are used to compute the mutual information and …


3d Speaker Geometry Inference From Digital Video Using 2d Projective Geometry, Sebastian Alonso Janampa Rojas Apr 2023

3d Speaker Geometry Inference From Digital Video Using 2d Projective Geometry, Sebastian Alonso Janampa Rojas

Electrical and Computer Engineering ETDs

The thesis discusses the need for a 3D world model reconstruction from raw video frames using 2D projective geometry. We propose a computer-aided approach to reconstructing a 3D speaker geometry from classroom videos of students learning Python.

The proposed method uses a transformer model to detect line candidates. Once the users identify lines corresponding to three orthogonal directions, the method computes the three vanishing points and the camera matrix. The method identifies the student’s mouths based on face landmark detection. After the estimates of the projections of the students’ mouths on the table are verified by the users, the proposed …


A Systematic Review On High Flux And Medium Cut Off Membranes – Benchmarking Using Simulation Models, Ahana Fatima Alex, R Vinoth, Ravishankar Dudhe Apr 2023

A Systematic Review On High Flux And Medium Cut Off Membranes – Benchmarking Using Simulation Models, Ahana Fatima Alex, R Vinoth, Ravishankar Dudhe

Manipal Research Colloquium - 2023

Manipal Research Colloquium- 2023 aims to bring students, scholars, and scientists to this forum where discussion on a diverse range of topics from various streams (Health Sciences, Technical Sciences, Basic & Applied Sciences, Humanities & Social Sciences, and Management Sciences) will be taking place.


Eben Cabs (Mobility As A Service), Asha Kumari Apr 2023

Eben Cabs (Mobility As A Service), Asha Kumari

Manipal Research Colloquium - 2023

Manipal Research Colloquium- 2023 aims to bring students, scholars, and scientists to this forum where discussion on a diverse range of topics from various streams (Health Sciences, Technical Sciences, Basic & Applied Sciences, Humanities & Social Sciences, and Management Sciences) will be taking place.


Current Trends In Brain Computer Interface : A Review, Bishal Kumar Gupta, Akash Kr Bhoi, Tawal Kumar Koirala Apr 2023

Current Trends In Brain Computer Interface : A Review, Bishal Kumar Gupta, Akash Kr Bhoi, Tawal Kumar Koirala

Manipal Research Colloquium - 2023

Manipal Research Colloquium- 2023 aims to bring students, scholars, and scientists to this forum where discussion on a diverse range of topics from various streams (Health Sciences, Technical Sciences, Basic & Applied Sciences, Humanities & Social Sciences, and Management Sciences) will be taking place.


A Solution To Unicode Phishing, Hari Om, Ritik Kumar, Saumya Das Apr 2023

A Solution To Unicode Phishing, Hari Om, Ritik Kumar, Saumya Das

Manipal Research Colloquium - 2023

Manipal Research Colloquium- 2023 aims to bring students, scholars, and scientists to this forum where discussion on a diverse range of topics from various streams (Health Sciences, Technical Sciences, Basic & Applied Sciences, Humanities & Social Sciences, and Management Sciences) will be taking place.


Data Analysis On Covid-19 Vaccination In India, Shashank Shekhar, Kumar Abhishek Apr 2023

Data Analysis On Covid-19 Vaccination In India, Shashank Shekhar, Kumar Abhishek

Manipal Research Colloquium - 2023

Manipal Research Colloquium- 2023 aims to bring students, scholars, and scientists to this forum where discussion on a diverse range of topics from various streams (Health Sciences, Technical Sciences, Basic & Applied Sciences, Humanities & Social Sciences, and Management Sciences) will be taking place.


Data-Driven Stochastic Optimal Control Using Hilbert Space Embeddings Of Distributions, Adam J. Thorpe Apr 2023

Data-Driven Stochastic Optimal Control Using Hilbert Space Embeddings Of Distributions, Adam J. Thorpe

Electrical and Computer Engineering ETDs

Autonomous systems are increasingly being deployed in complex environments subject to real-world uncertainty. For such systems, it may be exceptionally difficult or even impossible to compute a simple mathematical model of the system--for instance due to the presence of human elements, complex mechanics or system dynamics, or learning-enabled components. Data-driven control has recently gained significant attention in this area, where observations taken from the system evolution are used to compute an implicit representation of the system that is amenable to analysis and control. However, data-driven algorithms for control present new challenges, and require new insights to enable their use. The …


Potential Bioavailability Of Representative Pyrogenic Organic Matter Compounds In Comparison To Natural Dissolved Organic Matter Pools, Emily B. Graham, Hyun-Seob Song, Samantha Grieger, Vanessa A. Garayburu-Caruso, James C. Stegen, Kevin D. Bladon, Allison N. Myers-Pigg Apr 2023

Potential Bioavailability Of Representative Pyrogenic Organic Matter Compounds In Comparison To Natural Dissolved Organic Matter Pools, Emily B. Graham, Hyun-Seob Song, Samantha Grieger, Vanessa A. Garayburu-Caruso, James C. Stegen, Kevin D. Bladon, Allison N. Myers-Pigg

Department of Agricultural and Biological Systems Engineering: Faculty Publications

Pyrogenic organic matter (PyOM) from wildfires impacts river corridors globally and is widely regarded as resistant to biological degradation. Though recent work suggests PyOM may be more bioavailable than historically perceived, estimating bioavailability across its chemical spectrum remains elusive. To address this knowledge gap, we assessed potential bioavailability of representative PyOM compounds relative to ubiquitous dissolved organic matter (DOM) with a substrate-explicit model. The range of potential bioavailability of PyOM was greater than natural DOM; however, the predicted thermodynamics, metabolic rates, and carbon use efficiencies (CUEs) overlapped significantly between all OM pools. Compound type (e.g., natural versus PyOM) had approximately …


A Preliminary Study Of The Efficacy Of Using A Wrist-Worn Multiparameter Sensor For The Prediction Of Cognitive Flow States In University-Level Students, Josephine Graft, William Romine, Brooklynn Watts, Noah Schroeder, Tawsik Jawad, Tanvi Banerjee Apr 2023

A Preliminary Study Of The Efficacy Of Using A Wrist-Worn Multiparameter Sensor For The Prediction Of Cognitive Flow States In University-Level Students, Josephine Graft, William Romine, Brooklynn Watts, Noah Schroeder, Tawsik Jawad, Tanvi Banerjee

Computer Science and Engineering Faculty Publications

Engagement is enhanced by the ability to access the state of flow during a task, which is described as a full immersion experience. We report two studies on the efficacy of using physiological data collected from a wearable sensor for the automated prediction of flow. Study 1 took a two-level block design where activities were nested within its participants. A total of five participants were asked to complete 12 tasks that aligned with their interests while wearing the Empatica E4 sensor. This yielded 60 total tasks across the five participants. In a second study representing daily use of the device, …


Identify The Micro-Parameters For Optimized Discrete Element Models Of Granular Materials In Two Dimensions Using Hexagonal Close-Packed Structures, Xiaodong Zhou, Dongzhao Jin, Dongdong Ge, Siyu Chen, Zhanping You Apr 2023

Identify The Micro-Parameters For Optimized Discrete Element Models Of Granular Materials In Two Dimensions Using Hexagonal Close-Packed Structures, Xiaodong Zhou, Dongzhao Jin, Dongdong Ge, Siyu Chen, Zhanping You

Michigan Tech Publications, Part 1

The widely used simple cubic-centered (SCC) model structure has limitations in handling diagonal loading and accurately representing Poisson’s ratio. Therefore, the objective of this study is to develop a set of modeling procedures for granular material discrete element models (DEM) with high efficiency, low cost, reliable accuracy, and wide application. The new modeling procedures use coarse aggregate templates from an aggregate database to improve simulation accuracy and use geometry information from the random generation method to create virtual specimens. The hexagonal close-packed (HCP) structure, which has advantages in simulating shear failure and Poisson’s ratio, was employed instead of the SCC …


Effective Use Methods For Continuous Sensor Data Streams In Manufacturing Quality Control, William Hitchcock Apr 2023

Effective Use Methods For Continuous Sensor Data Streams In Manufacturing Quality Control, William Hitchcock

Senior Honors Theses

This work outlines an approach for managing sensor data streams of continuous numerical data in product manufacturing settings, emphasizing statistical process control, low computational and memory overhead, and saving information necessary to reduce the impact of nonconformance to quality specifications. While there is extensive literature, knowledge, and documentation about standard data sources and databases, the high volume and velocity of sensor data streams often makes traditional analysis unfeasible. To that end, an overview of data stream fundamentals is essential. An analysis of commonly used stream preprocessing and load shedding methods follows, succeeded by a discussion of aggregation procedures. Stream storage …


Energy-Specific Greenhouse Gas Emissions Measurements From 2-Stroke Marine Diesel Engine Using Liquefied Natural Gas, Kang-Ki Lee, Wilfried Hochegger, Alessandro Schonborn Apr 2023

Energy-Specific Greenhouse Gas Emissions Measurements From 2-Stroke Marine Diesel Engine Using Liquefied Natural Gas, Kang-Ki Lee, Wilfried Hochegger, Alessandro Schonborn

Articles

This study reports the energy specific air emissions from a diesel-cycle high pressure injection dual fuel engine for operation on liquefied natural gas and heavy fuel oil. An experiment at sea was performed onboard a bulk carrier during commercial voyages, to measure the efficiency of the engine and to measure air emissions relevant to air pollution and climate impact for operation on both fuels. The measurements showed that the energy conversion efficiency of the engine was higher for operation on liquefied natural gas because its lower NOx emissions permitted the use of a higher effective compression ratio whilst meeting the …