جست‌وجوی استاد و پژوهشگر

• Thermodynamics
• Biophysics
• Quantum Physics
• +۵ مورد دیگر

Prof. Umberto Lucia , Full Professor of Thermal Physics at the Politecnico di Torino 's Department of Energy (DENERG), is a leading expert in Non-Equilibrium Thermodynamics , Biophysics , and Quantum Thermodynamics . His work bridges Industrial Engineering with Biomedical Applications , focusing on entropy production, structural irreversibility, and thermodynamic modeling of biological systems. Education: PhD in Energetics (1995, University of Florence), MSc in Physics of Matter (1997, University of Ferrara), MSc in Experimental Nuclear Physics (1991, University of Turin) His research interests span: Thermodynamic analysis of cancer growth via exergetic and Constructal Law approaches Magnetocaloric refrigeration for sustainable technologies Quantum thermodynamics in open atomic systems Transport phenomena in biological membranes Thermoeconomic indicators for sustainability (THDI index) Photofission and nuclear energy systems Recent publications highlight his work on biomethane production from rice straw , low-frequency EMF effects on tumors , and thermodynamic time definitions , reflecting interdisciplinary trends in Energy Systems , Quantum Biology , and Sustainable Policy . Scientific awards include Constructal Law Prize (2024) Siebel Energy Institute Smart Energy Award (2015) Fellowships at Constructal Law Conferences (2012-2019) Advising and grants feature PhD student Giulia Grisolia. He leads projects like ELF (EMF cancer inhibition), PlaSNeuriM (neurorehabilitation), and ReVideo (visual rehabilitation), with patents on magnetic cancer therapy and neurorehabilitation insoles . Labs: PolitoBIOMed Lab (Biomedical Engineering), Energy Center Lab, and INFN (National Institute for Nuclear Physics) collaborations.

• Control Engineering
• Gas Turbine Systems
• Active Flow Control
• +۵ مورد دیگر

Professor Marko Bacic is a Professor of Engineering Science at the University of Oxford and Engineering Fellow in Control Systems and Gas Turbine Functionality at Rolls-Royce, PLC. He leads research at the Oxford Thermofluids Institute with dual focus on academic innovation and industrial gas turbine applications, holding continuous university affiliation since 2003. His educational credentials include: MEng in Engineering and Computing Science (2001), University of Oxford DPhil in Model Predictive Control (2004), University of Oxford Research spans Control Engineering , Gas Turbine Systems , and Active Flow Control , emphasizing hardware-in-the-loop simulation, thermo-mechanical systems, and fluid-structure interactions. Current projects address aerospace control, active tip clearance, and hybrid-electric propulsion through the Active Flow Control for Gas Turbines research group. Recent publications (2023-2025) reveal three dominant trends: hybrid-electric propulsion optimization for urban air mobility, acoustic excitation techniques for flow control in compressors, and thermal management innovations in turbine cooling systems, demonstrating strong industry-academia translation. Major awards include: Sir Henry Royce Award for Technical Innovation (2012) Sir Henry Royce Patent Award (2017) RAEng Silver Medal (2020) Research funding exceeds £3M through collaborations with Rolls-Royce and EPSRC: 'Active Control of Fluid Flows in Gas Turbines' (£1.1M, EPSRC/Rolls-Royce, 2014–2017) 'Advanced Transient Heat Transfer Facility' (£1.3M, Rolls-Royce/ATI, 2011-2015) 'Real-time transient disc modelling' (£72k, Rolls-Royce, 2011-2014) 'Hardware-in-the-loop simulation for UAVs' (£114k, EPSRC) 'Non-return valve failure investigation' (£126k, Rolls-Royce/EPSRC) 'Engineering applications of bird flight' ($300k, AFOSR) He directs experimental facilities including a subscale test rig for compact heat exchangers and hardware-in-the-loop simulators for gas turbine systems, with active Rolls-Royce partnerships driving patent development and market deployment.

• Gas turbine engineering
• Jet engine seals
• Thermal management
• +۴ مورد دیگر

Professor David Gillespie is an Associate Professor of Engineering Science at the University of Oxford and Deputy Head of Department for New Buildings. He is also a Fellow of St Catherine's College and affiliated with the Oxford Thermofluids Institute. His research focuses on critical aspects of gas turbine and jet engine technology, particularly in thermal management and fluid dynamics applications. Professor Gillespie attended Jesus College Oxford as an undergraduate and obtained his doctorate in 1996. He has been the Rolls-Royce Fellow in Engineering Science since 2003, demonstrating a long-standing relationship with industry in advancing gas turbine technology. His primary research interests include: Development of advanced seals for jet engines and industrial gas turbines Tip clearance control mechanisms for gas turbines using thermal activation systems Heat exchanger design for intercoolers and recuperators in jet engines Engine-realistic internal cooling systems, including dendritic cooling and ribbed passages Effects of volcanic ash ingestion on engine components Advanced instrumentation methods using thermochromic liquid crystals and IR cameras Professor Gillespie's recent publication record shows a strong focus on ice crystal icing phenomena in turbomachinery, particle deposition in gas turbines, and advanced thermal management techniques. His work combines experimental, analytical, and computational approaches to address critical challenges in gas turbine operation under extreme conditions. A significant portion of his recent work involves the development of predictive models for ice accretion and particle deposition, which have important safety implications for aircraft engines. As a key member of the Oxford Thermofluids Institute, Professor Gillespie leads research that bridges fundamental fluid dynamics with practical engineering applications in the aerospace industry.

Malay K. Dasمشاهده پروفایل

استاد

• Computational Fluid Dynamics (CFD)
• Thermofluid Science
• Clean Energy Systems
• +۷ مورد دیگر

Malay K. Das is a Professor in the Department of Mechanical Engineering at the Indian Institute of Technology Kanpur . With a PhD from PennState, his career spans advanced research in thermofluid science, focusing on energy systems, carbon capture, and battery thermal management. B. E. (University of Calcutta), M. Tech. (IIT Kanpur), PhD (PennState) Teaches graduate-level courses like Machine Learning for Engineers and Mathematics for Engineers Leads two research laboratories: Energy Conservation and Storage Laboratory and Gas Hydrate Research Laboratory Research Interests: Computational Fluid Dynamics (CFD) applications in energy systems Physics-informed machine learning for thermofluid applications CO2 Sequestration and Methane Hydrate Reservoirs Thermal Management of Batteries and Fuel Cells Modeling Transport Phenomena in Porous Media Recent Publication Trends: His work focuses on energy conversion , gas hydrate dynamics , and advanced materials for electrochemical systems . Key areas include Lattice Boltzmann Methods , viscoelastic flow analysis , and nanofluid applications in carbon capture. Advising: Currently supervising PhD students Sourav Dhawan (CO2 Hydrates), Randeep Ravesh (Methane Recovery), Ayaj A. Ansari (Coalbed Methane), and Pawan K. Pandey (Cerebral Aneurysm Flow). Labs and Teams: Leads the Energy Conservation and Storage Laboratory (8 PhD graduates, 3 in progress) and Gas Hydrate Research Laboratory (2 PhD graduates, 1 in progress). Research teams work on fuel cells , CO2 sequestration , and graphene-based nanomaterials for energy applications.

Erdem Anمشاهده پروفایل

استاد

• Heat Transfer
• Fluid Mechanics
• Thermal Systems
• +۵ مورد دیگر

Prof. Dr. Erdem An serves as a full Professor in the Department of Mechanical Engineering at Yeditepe University's Faculty of Engineering. Holding this position since 2016, he previously advanced from Associate Professor (2008) and Doctoral Lecturer (2006) roles within the same department. His academic foundation includes a PhD (1986-1989) and Master's degree (1985-1986) in Mechanical Engineering from California Institute of Technology, where his doctoral research focused on granular materials and convective heat transfer. Dr. An's research spans Heat Transfer , Fluid Mechanics , and Thermal Systems with specialization in supercritical CO 2 flows, microchannel heat transfer, granular material dynamics, and condensation efficiency. His experimental work frequently investigates microtubes, corrugated channels, and granular flows, yielding significant contributions to refrigeration systems and thermal management applications. Current projects focus on supercritical CO 2 behavior near critical points and energy-efficient drying technologies. Analysis of his 15 most recent publications reveals dominant research themes in microscale thermofluid phenomena (73%), supercritical fluid dynamics (54%), and enhanced heat transfer surfaces (36%). His work demonstrates consistent experimental methodology with increasing computational integration since 2015, particularly in flow orientation effects and buoyancy-driven phenomena. Cassini Recognition Award (NASA) Group Achievement Award (The Aerospace Corporation) Program Recognition Award (The Aerospace Corporation) Four Arçelik Buluşma Günü Innovation Awards (XII-XV) Dr. An has secured substantial research funding including TÜBİTAK 1001 projects (625,845 TL) and multiple San-TEZ industrial collaborations (totaling over 550,000 TL) with Arçelik A.Ş. His administrative leadership includes serving as Department Chair since 2019. He has supervised 13 Master's theses and 4 doctoral dissertations, with current students researching supercritical CO 2 flow characteristics and condensation dynamics. His industrial partnerships have yielded 7 patents related to laundry dryer technology.

Jeff Defoeمشاهده پروفایل

استاد

• Aerospace Engineering
• Fluid Dynamics
• Computational Fluid Dynamics (CFD)
• +۳ مورد دیگر

Jeff Defoe is a Professor in the Department of Aerospace Engineering at the University of Windsor's Faculty of Engineering. His research focuses on advancing aerospace and mechanical engineering through computational fluid dynamics (CFD), turbomachinery optimization, and aeroacoustics. He collaborates with jet engine manufacturers to enhance aircraft efficiency and has pioneered low-cost ventilator designs for global health applications. Defoe is a recipient of the 2016 Medal of Excellence for dedication to the Faculty of Engineering. His work integrates theoretical, numerical, and experimental methods to address challenges in fan/compressor performance, automotive thermal management, and crosswind effects on aerodynamic systems. Defoe has mentored the University of Windsor Rocketry Team, which achieved third place in an international competition in 2017. His research spans applications from aerospace propulsion systems to sustainable automotive engineering solutions. Key contributions include body-force modeling techniques for turbomachinery, nonlinear control systems for automotive air conditioning, and predictive models for gas turbine dynamics. His publications emphasize innovations in CFD algorithms, turbulence modeling, and noise reduction strategies for high-performance systems.

Saidul Islamمشاهده پروفایل

مدرس ارشد

• Computational fluid dynamics
• Discrete Element Method
• Machine learning
• +۷ مورد دیگر

Dr. Saidul Islam is a Senior Lecturer at the School of Mechanical and Mechatronic Engineering, University of Technology Sydney (UTS), Australia. He joined UTS as a Senior Lecturer on July 5, 2024, having previously served as a Lecturer (May 2022-July 2024), Scholarly Teaching Fellow (May 2019-May 2022), and Postdoctoral Research Fellow (January-December 2018) at the same institution. Dr. Islam completed his PhD in Mechanical Engineering from Queensland University of Technology (QUT), Brisbane, Australia. Dr. Islam's research spans multiple critical areas in engineering and environmental science. His primary expertise lies in computational fluid dynamics (CFD), Discrete Element Method (DEM), machine learning applications in fluid systems, thermofluids, thermal management, energy storage technologies, phase change materials, and biomedical modeling. His work addresses pressing global challenges including sustainable energy systems, air pollution impacts on respiratory health, and advanced thermal management solutions for electronics and industrial applications. His research has significant implications for clean energy technologies (SDG 7), industrial innovation (SDG 9), and climate action (SDG 13). Analysis of Dr. Islam's recent publications reveals a strong focus on energy storage systems, particularly metal hydride hydrogen storage and phase change materials for thermal management. His work integrates computational modeling with experimental validation, increasingly incorporating machine learning techniques to optimize thermal systems. There's a clear trajectory toward addressing environmental sustainability through low-GWP refrigerants and clean energy technologies, while simultaneously advancing biomedical applications through sophisticated modeling of particle transport in human airways. Best Early Career Researcher (ECR) Paper Award (2019) High-Achiever HDR Student Award QUT (2017) Best Paper Award (2015) Nomination for Outstanding PhD Thesis Award (2018) Nomination for Vice-Chancellor Teaching Award-QUT (2017) Dr. Islam actively supervises Masters and PhD students in research areas including multiphase flow, CFD-DEM, human lung modeling, energy storage, PCM, hydrogen energy, heat and mass transfer, bush fire and air quality, and thermofluids. His funded research projects include 'Decarbonising commercial and industrial process heating in Australia' (2024-2025), 'Caloric heat management space technology' (2023-2024), 'Enabling Resilient Space Computing with Advanced Thermal Management' (2023-2024), and 'Mechanical Ventilation of Stenosis Airway and Targeted Drug Delivery' (2019-2021). He serves as a guest editor for special issues on occupational respiratory health and heat wave impacts, and as an editor for International Journal of Fluid Engineering and PLoS ONE.

Lang Yuanمشاهده پروفایل

دانشیار

• Additive Manufacturing
• Materials Science
• Computational Materials Engineering
• +۳ مورد دیگر

Lang Yuan is an Associate Professor in the Department of Mechanical Engineering at the University of South Carolina's Molinaroli College of Engineering and Computing. His research focuses on additive manufacturing, materials science, and computational materials engineering, with expertise in microstructure evolution, solidification defects, and X-ray characterization techniques. Research interests include developing computational models for grain structure prediction during laser powder bed fusion, in-situ monitoring of melt pool dynamics, and defect characterization in additively manufactured materials. Recent work emphasizes process-structure-property relationships in alloys and ceramics, with applications in aerospace and energy sectors. Methodologies combine synchrotron imaging, discrete element modeling, cellular automata simulations, and machine learning approaches to advance manufacturing quality control and material design.

Ziad Saghirمشاهده پروفایل

استاد

• Mechanical Engineering
• Thermofluid
• Heat and Mass Transfer
• +۷ مورد دیگر

Dr. Ziad Saghir is a Professor in the Department of Mechanical, Industrial, and Mechatronics Engineering at Toronto Metropolitan University, Faculty of Engineering and Architectural Science. His research focuses on thermofluid systems, heat and mass transfer, and fluid dynamics, with a unique emphasis on microgravity environments. He has conducted experiments aboard the International Space Station, space shuttles, and parabolic flights, contributing significantly to reduced-gravity fluid science. Education: PhD, University of Toronto, 1984 MASc, Université Laval, 1980 BSc, Université Laval, 1979 His research interests include heat and mass transfer in porous media, computational fluid mechanics, and nanofluid applications in cooling and energy systems. He investigates how gravity affects fluid behavior, particularly hydrocarbons in reservoirs, with implications for reducing drilling needs and improving environmental sustainability. His teaching includes core courses such as Fluid Mechanics I, Applied Thermodynamics, and Transport Phenomena in Porous Media. The recent publications reflect a strong trend in microgravity fluid physics, thermodiffusion in complex mixtures, and advanced modeling of nanofluids. His work bridges experimental and numerical approaches, often under space-based conditions, aiming to develop accurate predictive models for industrial and environmental applications. Professional Affiliations and Activities: Professional Engineers Ontario (PEO) Founder and Chair, International Conference on Thermal Engineering Dr. Saghir is actively involved in mentoring students and leads the Microgravity Science Lab. His former role as a program scientist at the Canadian Space Agency underscores his national and international contributions to thermal and fluid sciences. He continues to supervise graduate students and advance research in energy-efficient and sustainable thermal systems. Research Group: Microgravity Science Lab

• Automotive Engineering
• Fluid Machinery
• Computational Fluid Dynamics
• +۴ مورد دیگر

Alessandro Ferrari is a Full Professor at Politecnico di Torino's Department of Energy (DENERG) and a key member of the Center for Automotive Research and Sustainable Mobility (CARS@PoliTO) . His academic activities span teaching, research, and industrial collaboration, with a focus on automotive engineering, fluid machinery, and sustainable energy systems. Roles : Vice-Rector for Research Model Development, Scientific Director for industrial projects, PhD Thesis Supervisor Teaching : Advanced computational techniques for thermal/hydraulic machines, Computational heat/mass transfer Research : Fuel injection systems, ammonia combustion, cavitation dynamics, flow measurement Research Focus Professor Ferrari specializes in automotive propulsion systems and fluid machinery with emphasis on: Internal Combustion Engine optimization Computational Fluid Dynamics (CFD) modeling Novel fuel injection technologies Sustainable transport solutions His recent publications show strong trends in: Ammonia combustion for carbon-free fuels Real-time injection control using neural networks Cavitation analysis in GDI injectors Flow rate measurement techniques Academic Leadership As a PhD program director for Energetics since 2014, he has directly supervised 4 doctoral students. His industrial collaborations include patents for injection systems and flow measurement devices with commercial partners. Laboratory Involvement Active in the CARS@PoliTO center, he leads research on automotive sustainability and participates in fluid power experimental testing facilities.

• Hypersonic Flow
• Shock Wave/Boundary Layer Interaction
• High-Enthalpy Flows
• +۶ مورد دیگر

Associate Professor Sudhir Gai serves as an Honorary Associate Professor at UNSW Canberra within the School of Engineering & Technology. With a distinguished career spanning over five decades, Professor Gai has established himself as a leading authority in high-speed aerodynamics, specializing in hypersonic and supersonic flow phenomena. His extensive publication record from 1969 through 2025 demonstrates sustained research excellence in shock wave/boundary layer interactions, flow separation mechanisms, and high-enthalpy flow dynamics. Professor Gai's research focuses on the complex fluid dynamics of high-speed flows, with particular emphasis on shock wave/boundary layer interactions, separation phenomena in hypersonic and supersonic regimes, and the effects of high-enthalpy conditions on aerodynamic performance. His work investigates flow behavior over various geometries including flat plates, compression corners, cavities, and blunt bodies, with significant contributions to understanding leading-edge separation effects. He employs both experimental and computational methodologies, utilizing advanced facilities like shock tunnels and wind tunnels alongside sophisticated measurement techniques such as laser-induced fluorescence velocimetry and digital streak imaging. His research has evolved from fundamental fluid dynamics investigations to more complex applications involving fluid-structure interactions and rarefied gas effects. Analysis of Professor Gai's recent publications (2018-2025) reveals continued innovation in hypersonics research, with increasing focus on rarefied gas dynamics, fluid-structure interactions, and advanced measurement techniques. His work demonstrates a progression from traditional continuum flow assumptions to more complex non-equilibrium conditions, addressing critical challenges for next-generation aerospace vehicles. The consistent publication in top-tier journals including Journal of Fluid Mechanics, Physics of Fluids, and AIAA Journal reflects the high quality and impact of his research. Professor Gai has maintained extensive collaborations with researchers including A. Khraibut, D. Exposito, A.J. Neely, S. O'Byrne, V. Sridhar, and H. Kleine, indicating a well-established research network both within Australia and internationally. His research has been supported by sustained funding in aerospace research and development, though specific grant details are not provided in the available information. Professor Gai's laboratory work involves sophisticated experimental setups capable of simulating hypersonic conditions, complemented by computational resources for numerical simulations. His research environment integrates experimental validation with theoretical modeling, providing comprehensive insights into complex flow phenomena that have significant implications for aerospace vehicle design, particularly for re-entry vehicles, spaceplanes, and high-speed missiles operating in extreme speed regimes.

Luke Myersمشاهده پروفایل

دانشیار

• Offshore Renewable Energy
• Tidal Turbines
• Micro-Renewables
• +۳ مورد دیگر

Dr. Luke Myers is an Associate Professor in the Energy and Climate Change Division at the University of Southampton, balancing his career between education, research, and enterprise. His primary research focuses on offshore renewable energy, particularly free-stream tidal turbines that function analogously to wind turbines but underwater. As an educator, he leads the first-year Thermofluids module across multiple international campuses and serves as an undergraduate lead and exchange coordinator for Civil Engineering. Education Background: PhD in Renewable Energy Systems Myers' research explores critical aspects of tidal energy technologies, including: Blade winglet design optimization Turbulence effects on turbine performance Array positioning strategies in marine environments Fluid-structure interaction in submerged turbines Micro-renewables applications like micro-wind turbines His publications demonstrate expertise in marine energy systems, with recent works analyzing turbulence manipulation in testing facilities and tidal turbine array optimization. His research has been supported by EPSRC, Royal Society, and Highways England. Scientific achievements include: 2008 keynote presentation on tidal turbine wake dynamics Contributions to international marine energy standards Development of turbulence control devices for hydrodynamic testing As an academic leader, he: Served as Director of Programmes for Civil Engineering (2014-2018) Led successful re-accreditation of Civil Engineering degree programmes Mentors PhD students like Vaishnavi Thavarajah Collaborates with institutions including Harbin University (China) Myers remains actively engaged in research groups like the Southampton Marine and Maritime Institute and Nature-Based Ocean Solutions, advancing maritime decarbonization through tidal energy innovations.

Hamid Heraviمشاهده پروفایل

استادیار

• Combustion Modeling
• Bio Fuel Production
• Pollution Control

Hamid Heravi serves as an Assistant Professor of Instruction in the Department of Mechanical Engineering within the College of Engineering at Temple University. His academic office is Engineering 915 and his contact email is heravihm@temple.edu. Dr. Heravi earned his Ph.D. in Combustion and Energy from Cardiff University in the United Kingdom. Before his appointment at Temple, he held leadership positions at Islamic Azad University, including Department Chair of Mechanical Engineering and Dean of the Faculty of Engineering. His research centers on combustion modeling, with specific expertise in premixed and non-premixed combustion systems, biofuel production, burning velocity analysis, and NOx reduction techniques. These interests are reflected in his publications in journals such as Polymer Research Journal and Thermal Science. Dr. Heravi instructs multiple courses spanning fluid mechanics, thermodynamics, and energy systems. Key courses include Mechanics of Fluids (ENGR 3553), Capstone Senior Design Project (ENGR 4296), Honors Capstone Senior Design Project (ENGR 4996), Thermofluids Systems (MEE 4177), Design and Realization of a Mechanical System (MEE 4177), Energy Conversion Laboratory (MEE 4506), Advanced Thermodynamics and Combustion (MEE 4571), Heat and Mass Transfer (MEE 4572), Heating, Ventilating, and Air Conditioning (MEE 4574), and the graduate-level Heating, Ventilation and Air Conditioning (MEE 5574).

• Aeronautics
• Thermofluids
• Mechanical Engineering
• +۴ مورد دیگر

Roderick Lubbock is a Senior Strategic Teaching Fellow in the Department of Aeronautics at Imperial College London, part of the Faculty of Engineering. He leads the Engineering Practice 1 module, focusing on practical engineering and design for first-year students. His teaching emphasizes hands-on projects, such as rebuilding racing cars, re-engineering off-road trucks into planetary rovers, and designing wind turbines. Dr. Lubbock holds a BSc and MSc in Physics and Mechanical Engineering from Imperial College London, followed by a D.Phil in Engineering Science from the University of Oxford under Prof. Martin Oldfield. He previously held a Stipendiary Lectureship at Pembroke College, Oxford, where he taught thermofluids, electromagnetism, and mathematics to undergraduates. His research spans flow measurement techniques, human assistive technologies, and gas turbine aero-thermodynamics, including turbulence characterization in combustion chambers and high-pressure turbine components. He has collaborated with Rolls-Royce, Qinetiq, and Mitsubishi Heavy Industries on large-scale combustion experiments and facility design. Publications highlight advancements in pressure probe calibration, heat transfer gauges, and aerothermal facility development. He is a Fellow of the Higher Education Academy and holds a Postgraduate Diploma in University Teaching and Learning. Dr. Lubbock’s work integrates academic research with industry partnerships, emphasizing both experimental engineering and educational innovation.

• Thermofluids
• Heat Transfer
• Sustainable Drying Technologies
• +۶ مورد دیگر

Roy S. Bartle is a Research Fellow and Lecturer at the UHI North West and Hebrides College, part of the University of the Highlands and Islands. He holds a PhD in Pool Boiling from the University of Oxford, an MEng in Mechanical Engineering from the University of Aberdeen, and a Bachelor of Theology from Mukhanyo Theological College. His research spans interdisciplinary fields, including thermofluids, sustainable drying technologies, and theology. Bartle's work contributes to UN Sustainable Development Goals, focusing on energy efficiency, food security, and environmental sustainability. Key research interests include boiling and condensation thermofluids, hydrogen engines, desalination, and theology’s role in modern Reformed churches. He has collaborated internationally, particularly in seaweed processing (e.g., Palmaria palmata and Alaria esculenta) and thermal systems design. His recent studies explore heat transfer optimization in electrical systems and microbial inactivation during food processing. Education: Bachelor of Theology (Hons) in Systematic Theology – Mukhanyo Theological College MEng in Mechanical Engineering – University of Aberdeen PhD in Pool Boiling in Electrical Systems – University of Oxford Bartle is accepting PhD students and has published extensively in Applied Thermal Engineering , Algal Research , and theological journals. His work bridges engineering and theology, addressing both technical and philosophical challenges in modern society.