Notice: For the latest information and guidance on Purdue's response to COVID-19 please visit: https://coronavirus.purdue.edu/students

Courses By School

Aeronautics and Astronautics
Course Number Course Name Credit 2021 2022 2023 2024 2025
AAE50700 Principles of Dynamics 3 Fall - Fall - Fall
AAE50800 Optimization in Aerospace Engineering 3 - Fall - Fall -
AAE51100 Introduction to Fluid Mechanics 3 - Fall - Fall -
AAE51200 Computational Aerodynamics 3 - Spring - Spring -
AAE51400 Intermediate Aerodynamics 3 Spring - Spring - Spring
AAE51900 Hypersonic Aerothermodynamics 3 - Spring - - -
AAE52300 Introduction to Remote Sensing 3 - Spring - Spring -
AAE53200 Orbit Mechanics 3 - Fall - Fall -
AAE53400 Spacecraft Electric Propulsion 3 - Fall - Fall -
AAE53700 Hypersonic Propulsion 3 Fall - Fall - Fall
AAE53800 Air Breathing Propulsion 3 - Fall - Fall -
AAE53900 Advanced Rocket Propulsion 3 Spring Spring - Spring -
AAE54800 Mechanical Behavior of Aerospace Materials 3 - Fall - Fall -
AAE55000 Multidisciplinary Design Optimization 3 Fall Fall Fall Fall Fall
AAE55200 Nondestructive Evaluation of Structures and Materials 3 Spring Spring Spring Spring Spring
AAE55300 Elasticity in Aerospace Engineering 3 Fall Fall Fall Fall Fall
AAE55400 Fatigue of Structures and Materials 3 Fall - Fall - Fall
AAE55500 Mechanics of Composite Materials 3 Spring Spring Spring Spring Spring
AAE55800 Finite Element Methods in Aerospace Structures 3 Fall Fall Fall Fall Fall
AAE56000 System of Systems Modeling and Analysis 3 Spring Spring Spring Spring Spring
AAE56100 Intro to Convex Optimization 3 - Fall - Fall -
AAE56400 Systems Analysis and Synthesis 3 Fall Fall - Fall -
AAE56800 Applied Optimal Control And Estimation 3 - Spring - Spring -
AAE57500 Introduction to Satellite Navigation and Positioning 3 Fall - Fall - Fall
AAE59000 Aerospace Propulsion 3 Fall - Fall - Fall
AAE59000 Data Science in Mechanics of Materials 3 - - Spring - Spring
AAE59000 Molecular Gas Dynamics 3 - Fall - Fall -
AAE59000 Multi-Agent Autonomy and Control 3 - Spring - Spring -
AAE59000 Nonequilibrium Hypersonic Flows 3 Spring - Spring - Spring
AAE59000 Plasmas and Electric Discharges 3 - - - Spring -
AAE59000 Space Flight Operations 3 Fall Fall Fall Fall Fall
AAE59000 Space Traffic Management 3 - Fall - Fall -
AAE59000 Spacecraft Attitude Dynamics 3 Spring - Spring - Spring
AAE59000 System Safety and Reliability 3 Fall Fall Fall Fall Fall
AAE60700 Variational Principles of Mechanics 3 Spring - Spring - Spring
AAE62400 Laminar-Turbulent Transition 3 Spring - - - Spring
AAE62600 Turbulence and Turbulence Modeling 3 Spring - Spring - Spring
AAE63200 Advanced Orbital Dynamics 3 Fall - Fall - Fall
AAE65400 Fracture Mechanics 3 - Spring - Spring -
AAE66600 Nonlinear Dynamics, Systems and Control 3 - - - Spring -
AAE67500 Advanced Signals and Systems for Satellite Navigation 3 - - Spring - -
AAE69000 Multiscale Structural Mechanics 3 - - Fall - -
AAE69000 Orbital Perturbations 3 - Spring - Spring -

Agricultural and Biological Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
ABE59100 Polymeric Biomaterials 3 Spring Spring Spring - Spring

Biomedical Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
BME50100 Biostatistics 3 Fall Fall Fall Fall Fall
BME51100 Biomedical Signal Processing 3 Fall Fall Fall Fall Fall
BME52100 Biosensors: Fundamentals and Applications 3 - Fall - Fall -
BME55600 Introduction to Clinical Medicine 3 Fall - Fall - Fall
BME56100 Preclinical and Clinical Study Design 3 Fall
Spring 		Fall Fall Fall Fall
BME56200 Regulatory Issues Surrounding Approval of Biomedical Devices 3 - Spring Spring Spring Spring
BME56300 Quality Systems for Regulatory Compliance 3 - Summer Summer Summer Summer
BME56400 Ethical Engineering of Medical Tech 3 - Spring Spring Spring Spring
BME58100 Fundamentals of MEMS 3 Spring Spring Spring - -
BME59500 Human Motion Kinetics 3 - - - Spring -
BME59500 Medical Imaging Diagnostic Technologies 3 Fall Fall Fall Fall Fall
BME59500 Neural Mechanisms of Health and Disease 3 Spring - Spring - Spring
BME59500 Polymeric Biomaterials 3 Spring Spring Spring - Spring

Civil Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
CE51300 Lighting and Daylighting Design of Buildings 3 - Spring Spring Spring -
CE52200 Computer Applications in Construction 3 - - Spring Spring -
CE54300 Coastal Engineering 3 - Fall Fall Fall -
CE54900 Computational Watershed Hydrology 3 - Fall
Spring 		Fall Fall -
CE55000 Physico/Chemical Processes in Environmental Engineering 3 Fall - - - -
CE57000 Advanced Structural Mechanics 3 - Fall - - -
CE57300 Structural Dynamics 3 -
Spring 		- - -
CE59700 Analysis and Design of Water Distribution Systems 1 Fall - - - -
CE59700 BIM for Construction 1 - Spring - - -
CE59700 Biological Principles in Wastewater Treatment 1 - Spring - - -
CE59700 Biological Wastewater Treatment 3 - - - Spring -
CE59700 Computer Applications of Artificial Intelligence and eConstruction 1 - Spring - - -
CE59700 Connections in Steel 1 Spring - - - -
CE59700 Data Science for Smart Cities 3 Spring Fall - Spring -
CE59700 Design of Sanitary Sewer Systems 1 Fall - - - -
CE59700 Design of Steel-Concrete Composite 1 Spring - - - -
CE59700 Design of Urban Water Management Structures 1 Fall - - - -
CE59700 Elastic Stability and Behavior of Members 1 Summer - - - -
CE59700 Electrical-Based Non-Destructive Testing and Sensing 1 Spring - - - -
CE59700 Fundamentals of Building Information Modeling 1 - Spring - - -
CE59700 Fundamentals of Nanomaterials and Nanotech 1 Fall Fall Fall Fall Fall
CE59700 Fundamentals of Non-Destructive Testing 1 Spring - - - -
CE59700 Fundamentals of Prestressed Concrete 1 Spring - Spring - -
CE59700 Geographic Information Systems 3 Spring Spring Spring - -
CE59700 Geospatial Data Analytics 3 - Spring - - -
CE59700 Global Sustainable Engineering 3 - Fall - Fall -
CE59700 Groundwater Contamination 1 Spring Spring Spring Spring -
CE59700 Groundwater Cycle 1 Spring Spring Spring Spring -
CE59700 Logistics and Supply Chains 3 Fall - Spring Fall -
CE59700 Modern Biotechnologies for Wastewater Treatment 1 - Spring - - -
CE59700 Nano-device for Energy Harvesting and Sensing 1 Fall Fall Fall Fall Fall
CE59700 Nanomaterials for Civil and Environmental Engineering 1 Fall Fall Fall Fall Fall
CE59700 Network Models for Connected and Autonomous Vehicles 3 Fall Spring - - -
CE59700 Nutrient Removal and Resource Recovery in Wastewater 1 - Spring - - -
CE59700 Plastics in Infrastructure and the Environment 3 Summer Summer - - -
CE59700 Post-tensioned Structures 1 Spring - Spring - -
CE59700 Pretensioned Structures 1 Spring - Spring - -
CE59700 Stability and Design of Structural Frames 1 Summer - - - -
CE59700 Stability and Design of Structural Members 1 Summer - - - -
CE59700 Steel Beam and Plate Girder 1 Spring - - - -
CE59700 UAS Based LiDAR Mapping 1 - Spring - - -
CE59700 UAS Based Mapping: Basic Principles 1 - Spring - - -
CE59700 UAS Based Photogrammetric Mapping 1 - Spring - - -
CE59700 Water Chemistry for Environmental and Ecological Engineering 3 - Spring - - -
CE59700 Wave-Based NDT Methods 1 Spring - - - -
CE59700 Wells Hydraulics 1 Spring Spring Spring Spring -
CE63100 Advanced Concrete and Aggregates 3 Summer Spring - - -
CE69700 Photochemical Reactors: Theory, Methods & Applications 3 - Spring - - -

Construction Engineering and Management
Course Number Course Name Credit 2021 2022 2023 2024 2025
CEM59700 Accounting and Finance for Managing Construction 3 - Summer - Spring -
CEM59700 Asset Management for Buried Pipelines 3 Fall Fall Fall - Fall
CEM59700 Construction Productivity 3 Fall - Fall - Fall
CEM59700 Development of Underground Space 3 Spring Spring - Spring -
CEM59700 Requirements and Implementation of ISO 41001 3 Spring Spring
Summer 		Fall
Spring 		- Fall
Spring
CEM59700 Temporary Structures - Buildings 1 - Summer - - -
CEM59700 Temporary Structures - Vertical Construction Module 1 - Spring Fall - Fall

Chemical Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
CHE59700 Analytical Approach to Healthcare Delivery 3 Summer - - - -
CHE59700 Medical Devices: Dev and Clin App 3 Summer - - - -
CHE59700 Smart Manufacturing in the Process Industries 3 - Spring - - -

Computer Science
Course Number Course Name Credit 2021 2022 2023 2024 2025
CS51500 Numerical Linear Algebra 3 Fall - - - -
CS52500 Parallel Computing 3 Spring - - - -
CS54100 Database Systems 3 Fall - - - -
CS57800 Statistical Machine Learning 3 Fall - - - -

Electrical and Computer Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
ECE50863 Computer Network Systems 3 Fall
Spring 		- Spring Spring Spring
ECE51012 Electromechanics 3 Spring Spring Spring Spring Spring
ECE51018 Hybrid Electric Vehicles 3 Spring Fall
Spring 		Fall Fall Fall
ECE51300 Diffraction, Fourier Optics and Imaging 3 Fall - Fall - Fall
ECE53800 Digital Signal Processing I 3 Fall Fall Fall Fall Fall
ECE54400 Digital Communications 3 - Fall - Fall -
ECE54700 Introduction to Computer Communication Networks 3 - Fall Fall Fall Fall
ECE55200 Introduction to Lasers 3 Spring Spring Spring Spring Spring
ECE56500 Computer Architecture 3 Fall - - - -
ECE56800 Embedded Systems 3 - Spring - - -
ECE58000 Optimization Methods for Systems and Control 3 - Spring Spring Spring Spring
ECE59500 Boltzmann Law: Physics to Machine Learning 1 Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer
ECE59500 Computer Vision for Embedded Systems 1 Fall - Fall - Fall
ECE59500 Essentials of Transistors 1 Spring Spring Spring Spring Spring
ECE59500 Fundamentals of Current Flow 1 Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer
ECE59500 Intro to Compilers: Code Generation 1 Fall Fall Fall Fall Fall
ECE59500 Intro to Compilers: Compiler Basics 1 Fall Fall Fall Fall Fall
ECE59500 Intro to Compilers: Optimization 1 Fall Fall Fall Fall Fall
ECE59500 Intro to Data Mining 3 Fall Fall Fall Fall Fall
ECE59500 Intro to Electronics Packaging and Heterogeneous Integration 3 - Spring - - -
ECE59500 Intro to Quantum Science & Tech 3 Fall Fall Fall Fall Fall
ECE59500 Intro to the Internet of Things I 1 - Fall Fall Fall Fall
ECE59500 Intro to the Internet of Things II 1 - Fall Fall Fall Fall
ECE59500 Intro to the Internet of Things III 1 - Fall Fall Fall Fall
ECE59500 Introduction to Deep Learning 3 Fall Fall Fall Fall Fall
ECE59500 Introduction to Quantum Transport 1 Fall
Spring 		Fall
Spring
Summer 		Fall
Spring 		Fall
Spring 		Fall
Spring
ECE59500 Power Semiconductor Devices 1 - Summer - - -
ECE59500 Quantum Computing I: Fundamentals 1 Spring Spring Spring Spring Spring
ECE59500 Quantum Computing II: Hardware 1 Spring Spring Spring Spring Spring
ECE59500 Quantum Computing III: Algorithm & Software 1 Spring Spring Spring Spring Spring
ECE59500 Semiconductor Fundamentals 1 Spring Spring Spring Spring Spring
ECE59500 Stories of Success: From our Alums and Corporate Partners 1 - Spring - - -
ECE60000 Random Variables and Signals 3 Spring Spring Spring Spring Spring
ECE60200 Lumped System Theory 3 Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer
ECE60400 Electromagnetic Field Theory 3 Fall
Spring 		Fall
Spring 		Fall
Spring 		Fall
Spring 		Fall
Spring
ECE60600 Solid-State Devices 3 Fall
Spring 		Fall
Spring 		Fall
Spring 		Fall
Spring 		Fall
Spring
ECE60800 Computational Models and Methods 3 Fall
Spring 		Fall Fall Fall Fall
ECE61000 Energy Conversion 3 Fall Fall Fall Fall Fall
ECE61014 Electromagnetic and Electromechanical Component Design 3 Fall - Fall - Fall
ECE61016 Power Electronic Converters and Systems 3 - Fall - Fall -
ECE61700 Antennas: Design and Application 3 Spring - Spring - Spring
ECE63300 Modeling and Simulation of Power System Components 3 - - - Spring -
ECE63700 Digital Image Processing I 3 Spring - Spring - Spring
ECE68000 Modern Automatic Control 3 Fall - Fall - Fall
ECE69500 Advanced IoT Design and Applications 3 - Spring - - -
ECE69500 Big Data for Reliability and Security 1 Fall Fall Fall Fall Fall
ECE69500 Communication for Engineering Leaders 1 Spring
Summer 		Spring
Summer 		Spring
Summer 		Spring
Summer 		Spring
Summer
ECE69500 Epidemic Processes 1 Spring Spring Spring Spring Spring
ECE69500 Epidemics Over Networks 1 Spring Spring Spring Spring Spring
ECE69500 Fiber Optics Communications 1 - Spring - - -
ECE69500 Intro to Math for Systems & Control Theory 1 Spring Spring Spring Spring Spring
ECE69500 Nanophotonic Modeling 1 - Spring - - -
ECE69500 Primer on RF Circuit Design 1 Fall Fall Fall Fall Fall
ECE69500 Programmable Accelerator Architectures 3 Spring - Spring Spring Spring
ECE69500 Quantum Detectors 1 Spring Spring Spring Spring Spring
ECE69500 Quantum Detectors & Sensors 3 Fall
Spring 		Fall Fall Fall Fall
ECE69500 Quantum Networks 1 Spring Spring Spring Spring Spring
ECE69500 RF Design: Passive Active Components 1 Fall Fall Fall Fall Fall
ECE69500 RF System Design 1 Fall Fall Fall Fall Fall
ECE69500 Time Domain Simulation and Optimization for Design 1 Fall
Spring
Summer 		Fall
Spring 		Fall
Spring
Summer 		Fall
Spring
Summer 		Fall
Spring
Summer

Engineering Education
Course Number Course Name Credit 2021 2022 2023 2024 2025
ENE50101 Foundations of Engineering Education 3 Fall Fall Fall Fall Fall
ENE50200 History and Philosophy of Engineering Education 3 Fall Fall Fall Fall Fall
ENE50300 Engineering Education Inquiry 3 Fall Fall Fall Fall Fall
ENE50500 Theories of Development and Engineering Thinking 3 Spring Spring Spring Spring Spring
ENE50600 Content Assessment and Pedagogy: An Integrated Engineering Design Approach 3 Spring Spring Spring Spring Spring
ENE55400 Globalization and Engineering 3 Spring - - - -
ENE68500 Educational Methods in Engineering 3 Fall Fall Fall Fall Fall
ENE68700 Mentored Teaching in Engineering 1 Spring Spring Spring Spring Spring
ENE69000 Seminar in Engineering Education Fall
Spring 		Fall
Spring 		Fall
Spring 		Fall
Spring 		Fall
Spring
ENE69500 Succeeding as an Engineering Professor 3 Fall Fall Fall Fall Fall

GRAD
Course Number Course Name Credit 2021 2022 2023 2024 2025
GRAD59000 Program Management: A Comprehensive Overview of the Discipline 3 Summer Summer Summer Summer Summer

Industrial Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
IE53000 Quality Control 3 Fall - Fall - Fall
IE53300 Industrial Applications of Statistics 3 - Spring - Spring -
IE53500 Linear Programming 3 - Fall - Fall -
IE53600 Stochastic Models In Operations Research I 3 Spring - Spring - Spring
IE54500 Engineering Economic Analysis 3 - Fall - Fall -
IE54600 Economic Decisions in Engineering 3 Spring Spring Spring Spring Spring
IE55800 Safety Engineering 3 Spring - Spring - Spring
IE56600 Production Management Control 3 Summer Summer - - -
IE57000 Manufacturing Process Engineering 3 Fall - Fall - Fall
IE57400 Industrial Robotics & Flexible Assembly 3 - Spring - Spring -
IE57700 Human Factors in Engineering 3 Fall - Fall - Fall
IE57800 Applied Ergonomics 3 Fall - Fall - Fall
IE57900 Design and Control of Production and Manufacturing Systems 3 - Fall - Fall -
IE58000 Systems Simulation 3 - Fall - Fall -
IE58200 Advanced Facilities Design 3 Fall - Fall - -
IE59000 Big Data Risk Analytics for Engineering Management and Public Policy 3 Spring - Spring - -
IE59000 Human Factors of Medical Devices 3 Spring - Spring - Spring
IE59000 Project Management 3 - Spring - Spring -

Mathematics
Course Number Course Name Credit 2021 2022 2023 2024 2025
MA51100 Linear Algebra with Applications 3 Summer Spring
Summer 		Summer Summer Summer
MA52700 Advanced Mathematics for Engineers and Physicists I 3 Fall
Summer 		Fall
Spring
Summer 		Fall
Summer 		Fall
Summer 		Fall
Summer
MA52800 Advanced Mathematics for Engineers and Physicists II 3 Spring Spring Spring Spring Spring

Mechanical Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
ME50000 Advanced Thermodynamics 3 - Fall - Fall -
ME50100 Statistical Thermodynamics 3 Fall - Fall - Fall
ME50500 Intermediate Heat Transfer 3 Spring - Spring - Spring
ME50900 Intermediate Fluid Mechanics 3 Fall - Fall - Fall
ME51000 Gas Dynamics 3 Spring Spring Spring Spring Spring
ME51100 Heat Transfer in Electronic Systems 3 - Fall - Fall -
ME51300 Engineering Acoustics 3 Fall - Fall - Fall
ME51800 Analysis of Thermal Systems 3 Fall - Fall - Fall
ME52500 Combustion 3 Spring - Spring - Spring
ME53300 Turbomachinery 2 3 Fall - Fall - Fall
ME53900 Introduction to Scientific Machine Learning 3 Fall Fall
Summer 		Fall
Spring 		Fall
Spring 		Fall
Spring
ME54000 Internal Combustion Engines 3 - Fall - Fall -
ME54100 Engineering Design: A Decision-Based Perspective 3 - Fall Fall Fall Fall
ME55300 Product and Process Design 3 Fall
Spring 		Fall
Spring 		Fall
Spring 		Fall
Spring 		Spring
ME55400 Intellectual Property for Engineers 1 Fall
Spring 		Spring - - -
ME55600 Lubrication, Friction and Wear 3 Spring - Spring - Spring
ME55900 Micromechanics of Materials 3 Spring Spring Spring Spring Spring
ME56200 Advanced Dynamics 3 Spring Spring - - -
ME56300 Mechanical Vibrations 3 - Fall - Fall -
ME57000 Machine Design 3 - Fall - Fall -
ME57100 Reliability Based Design 3 Fall Fall Fall Fall Fall
ME57500 Theory and Design of Control Systems 3 - Fall - Fall -
ME57700 Human Motion Kinetics 3 - - - Spring -
ME57800 Digital Control 3 - - Spring - Spring
ME57900 Fourier Methods in Digital Signal Processing 3 - Spring - Spring -
ME58100 Numerical Methods in Mechanical Engineering 3 Fall Fall Fall Fall Fall
ME59700 Complex Fluids 3 Fall - Fall - Fall
ME59700 Data Analytics for Scientists and Engineers 3 Spring - - - -
ME59700 Decision Making in Engineering Design 3 Fall
Spring 		- - - -
ME59700 Electrochemical Energy Systems 3 - Spring - - -
ME59700 Intro to Electronics Packaging and Heterogeneous Integration 3 - Spring - - -
ME60800 Numerical Methods in Heat, Mass, and Momentum Transfer 3 - - - Spring -
ME61100 Principles of Turbulence 3 - Fall - - -
ME61400 Computational Fluid Dynamics 3 Fall - Spring - -
ME65000 Computational Fracture Mechanics 3 - Spring - Spring -
ME67500 Multivariable Control System Design 3 - Spring - - -
ME68100 Finite & Boundary Element Methods 3 Spring - Spring - Spring

Materials Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
MSE51000 Microstructural Characterization Techniques 3 - Spring - Spring -
MSE52700 Introduction to Biomaterials 3 Spring - Spring - Spring
MSE53000 Materials Processing in Manufacturing 3 - Spring - - -
MSE59700 Additive Manufacturing of Materials 3 Spring Spring Spring Spring Spring
MSE59700 Batteries 3 Summer - Summer - Summer
MSE59700 Lean Manufacturing 3 Spring Spring Spring Spring Spring
MSE59700 Mechanical Properties and Behaviors of Polymers 3 Fall - Fall - Fall
MSE59700 Steel and Aluminum: Processing Structure and Properties 3 - Fall - Fall -
MSE59700 Superalloys - High Temperature 3 - Spring - Spring -
MSE60000 Materials Engineering Fundamentals 3 Fall Fall Fall Fall Fall

Nuclear Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
NUCL50100 Nuclear Engineering Principles 3 Fall Fall
Summer 		Fall
Summer 		Fall
Summer 		-
NUCL50200 Nuclear Engineering Systems 3 Spring Spring Spring Spring -
NUCL51000 Nuclear Reactor Theory I 3 Spring Spring Spring Spring -
NUCL57000 Fuzzy Approaches In Engineering 3 Spring Spring - - -
NUCL57500 Neural Computing in Engineering 3 Fall Fall - - -
NUCL59700 Big Data and Machine Learning in Engineering 3 Fall - - - -

Statistics
Course Number Course Name Credit 2021 2022 2023 2024 2025
STAT51100 Statistical Methods 3 Spring
Summer 		- Spring
Summer 		- Spring
Summer
STAT51200 Applied Regression Analysis 3 Summer Summer Summer Summer Summer
STAT51300 Statistical Quality Control 3 Fall - Fall - Fall
STAT51400 Design of Experiments 3 - Fall - Fall -
STAT51600 Basic Probability and Applications 3 Fall - Fall - Fall
STAT51700 Statistical Inference 3 - Spring - Spring -
STAT54000 Quantitative Finance I 3 - - Spring - -

Systems Engineering
Course Number Course Name Credit 2021 2022 2023 2024 2025
SYS50000 Perspectives on Systems 3 Fall Fall Fall Fall Fall
SYS51000 Tools and Methodologies for Designing Systems 3 Fall Fall Fall Fall Fall
SYS53000 Practical Systems Thinking 3 Spring Spring Spring Spring Spring