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2018

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Full-Text Articles in Engineering

A Longitudinal Analysis On The Cyclical Pattern Of The U.S. Airline Industry, Michelle M. Bennett, Brent D. Bowen, Jacqueline R. Luedtke, Dean Headley, Timothy B. Holt Feb 2018

A Longitudinal Analysis On The Cyclical Pattern Of The U.S. Airline Industry, Michelle M. Bennett, Brent D. Bowen, Jacqueline R. Luedtke, Dean Headley, Timothy B. Holt

Publications

The Airline Quality Rating (AQR) is the nation’s most comprehensive study of airline performance and quality for over two decades. AQR provides consumers and industry watchers a means to compare performance quality among different US airlines using objective performance-based data. This research looks to analyze the cyclical patterns present in AQR in order to identify trends and factors contributing to the changes in these results each year. This research utilizes the application of a longitudinal analysis methodology which will provide the correlation between factors identified and the indicators affected.


Dual-Channel Warehouse And Inventory Management With Stochastic Demand, Fawzat Alawneh, Guoqing Zhang Feb 2018

Dual-Channel Warehouse And Inventory Management With Stochastic Demand, Fawzat Alawneh, Guoqing Zhang

Mechanical, Automotive & Materials Engineering Publications

This study examines the inventory policy for the emerging dual-channel warehouse, which has a unique structure where the warehouse is divided into two areas: one for fulfilling online orders and the other for storing products and fulfilling offline orders. A multi-item inventory model was developed considering the warehouse capacity constraint, demand, and lead time uncertainty. Solution methods are provided for both uniform and normal distributions. Adopting the proposed inventory policy for a dual warehouse is cost effective and adds flexibility to the warehouse and supply chain. The study also offers managerial insights on some critical issues faced by companies operating …


Unmanned Aerial Systems: Research, Development, Education & Training At Embry-Riddle Aeronautical University, Michael P. Hickey Jan 2018

Unmanned Aerial Systems: Research, Development, Education & Training At Embry-Riddle Aeronautical University, Michael P. Hickey

Publications

With technological breakthroughs in miniaturized aircraft-related components, including but not limited to communications, computer systems and sensors, state-of-the-art unmanned aerial systems (UAS) have become a reality. This fast-growing industry is anticipating and responding to a myriad of societal applications that will provide new and more cost-effective solutions that previous technologies could not, or will replace activities that involved humans in flight with associated risks.

Embry-Riddle Aeronautical University has a long history of aviation-related research and education, and is heavily engaged in UAS activities. This document provides a summary of these activities, and is divided into two parts. The first part …


Lowering Legal Barriers To Rpki Adoption, Christopher S. Yoo, David A. Wishnick Jan 2018

Lowering Legal Barriers To Rpki Adoption, Christopher S. Yoo, David A. Wishnick

All Faculty Scholarship

Across the Internet, mistaken and malicious routing announcements impose significant costs on users and network operators. To make routing announcements more reliable and secure, Internet coordination bodies have encouraged network operators to adopt the Resource Public Key Infrastructure (“RPKI”) framework. Despite this encouragement, RPKI’s adoption rates are low, especially in North America.

This report presents the results of a year-long investigation into the hypothesis—widespread within the network operator community—that legal issues pose barriers to RPKI adoption and are one cause of the disparities between North America and other regions of the world. On the basis of interviews and analysis of …


University Of Nebraska At Omaha 2018-2019 Course Catalog, University Of Nebraska At Omaha Jan 2018

University Of Nebraska At Omaha 2018-2019 Course Catalog, University Of Nebraska At Omaha

Undergraduate Catalogs

Located in one of America’s best cities to live, work and learn, the University of Nebraska at Omaha (UNO) is Nebraska’s premier metropolitan university. With more than 15,000 students enrolled in 200-plus programs of study, UNO is recognized nationally for its online education, graduate education, military friendliness, and community engagement efforts.Founded in 1908, UNO has served learners of all backgrounds for more than 100 years and is dedicated to another century of excellence both in the classroom and in the community.


Magic Triangle – Human, Exoskeleton, And Collaborative Robot Scenario, R. A. Goehlich, M. H. Rutsch, I. Krohne Jan 2018

Magic Triangle – Human, Exoskeleton, And Collaborative Robot Scenario, R. A. Goehlich, M. H. Rutsch, I. Krohne

Publications

The incidence of musculoskeletal disorders in workplaces with difficult ergonomic conditions is increasing. Today, there is a growing market for technical support systems that avoid repetitive strain on the musculoskeletal system. We have been observing two (parallel) lines of development: on the one hand, the development of exoskeletons supporting shop floor operators and, on the other hand, the development of collaborative robots for the creation of hybrid teams. The focus of our research is the combined application of exoskeletons AND collaborative robots for shop floor operators in the aerospace industry. Our approach is to analyze various scenarios to understand which …


A Design Methodology To Optimize Supply Chain Network Performance, Dheeraporn Nippaya, J. David Porter Jan 2018

A Design Methodology To Optimize Supply Chain Network Performance, Dheeraporn Nippaya, J. David Porter

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Organizations are constantly looking for new ways to reduce costs while still providing high customer service levels to face stringent competitive environments and the ever- increasing market globalization. An alternative these organizations can pursue to respond to these challenges and to gain a competitive differentiation is to optimize their supply chain network (SCN). This research aims to develop an effective SCN design strategy to locate facilities (i.e., plants and distribution centers) and to balance the allocation of customers to these facilities to satisfy capacity limitations and customer demands with minimum total cost and maximum level of service. It is anticipated …


On The Unique Features And Benefits Of On-Demand Distribution Models, Jennifer A. Pazour, Kaan Unnu Jan 2018

On The Unique Features And Benefits Of On-Demand Distribution Models, Jennifer A. Pazour, Kaan Unnu

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

To close the gap between current distribution operations and today’s customer expectations, firms need to think differently about how resources are acquired, managed and allocated to fulfill customer requests. Rather than optimize planned resource capacity acquired through ownership or long- term partnerships, this work focuses on a specific supply-side innovation – on-demand distribution platforms. On-demand distribution systems move, store, and fulfill goods by matching autonomous suppliers' resources (warehouse space, fulfillment capacity, truck space, delivery services) to requests on-demand. On-demand warehousing systems can provide resource elasticity by allowing capacity decisions to be made at a finer granularity (at the pallet-level) and …


A Space Syntax Analysis Of The Relationship Between Function And Form In Facility Layout, Alejandro Teran-Somohano, Alice E. Smith Jan 2018

A Space Syntax Analysis Of The Relationship Between Function And Form In Facility Layout, Alejandro Teran-Somohano, Alice E. Smith

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

This paper explores the relationship between a facility’s operation and its form using quantitative techniques provided by Space Syntax. Space Syntax provides quantitative metrics for characterizing the spatial traits of the locations within a facility which can then be related to operational metrics. Instances of the quadratic assignment problem are used to perform spatial and operational analyses on different flow matrices to study the resulting layouts. The effects of different objective functions on facility shapes are also studied.


Synthetic Order Data Generator For Picking Data, Mohammadnaser Ansari, Behnam Rasoolian, Jeffrey S. Smith Jan 2018

Synthetic Order Data Generator For Picking Data, Mohammadnaser Ansari, Behnam Rasoolian, Jeffrey S. Smith

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Sample data are in high demand for testing and benchmarking purposes. Like many other fields, warehousing and specifically order picking process are not exempt from the need for sample data. Sample data are used in order picking pro- cesses as a way of testing new methodologies such as new routing and new storage allocation approaches. Unfortunately, access to real order picking data is limited because of confidentiality and privacy issues which make it difficult to obtain practical results from the new methodologies. On the other hand, order data follows a highly complex and correlated structure that cannot be easily extracted …


A Practical Collaborative Material Handling Strategy For Cross-Docks, Hector J. Carlo, Stephanie Santiago-Montano Jan 2018

A Practical Collaborative Material Handling Strategy For Cross-Docks, Hector J. Carlo, Stephanie Santiago-Montano

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

The current operational paradigm at less-than- truckload (LTL) cross-dock industry (i.e., dedicated strategy) is to assign one material handler (MH) per inbound trailer. As a consequence, each loaded trip performed by a MH to move a load from the assigned inbound door to the loads’ corresponding outbound door is followed by an identical empty trip to return to the inbound door. This paper introduces the monomaniacal strategy as a practical rule-based material handling collaborative strategy for LTLs designed to minimize the total empty travel. In the monomaniacal strategy, after delivering a load to an outbound door, MHs travel counterclockwise to …


Improving The Environmental Sustainability Of Pallet Logistics Through Preemptive Remanufacturing: An Integer Linear Optimization Model, Fabiana Tornese, Jennifer Pazour, Andres L. Carrano, Brian K. Thorn Jan 2018

Improving The Environmental Sustainability Of Pallet Logistics Through Preemptive Remanufacturing: An Integer Linear Optimization Model, Fabiana Tornese, Jennifer Pazour, Andres L. Carrano, Brian K. Thorn

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

The use of pallets is crucial in handling and transportation processes and wooden pallet represent the most common packaging type in the US and in Europe. This work focuses on the environmental impact of wooden pallet reverse logistics, exploring the advantages of preemptive remanufacturing policies. Preemptive schedules allow the service provider to allocate transportation emissions across multiple pallet components, increasing the environmental efficiency of the transportation process. This advantage has to be compared to the lost opportunity of repairing a usable component earlier than required. An integer linear optimization model analyzes this trade-off and the benefits of a preemptive remanufacturing …


Integrated Intermodal Network Design With Nonlinear Inter-Hub Movement Costs, Mohammad Ghane-Ezabadi, Hector A. Vergara Jan 2018

Integrated Intermodal Network Design With Nonlinear Inter-Hub Movement Costs, Mohammad Ghane-Ezabadi, Hector A. Vergara

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

In this research, transportation mode and load route selection problems are integrated with the hub location problem in a single mathematical formulation to find the optimal design of intermodal transportation networks. Economies of scale are modeled utilizing a stepwise function that relates the per container transportation cost to the amount of flow between two nodes. A heuristic method combining a genetic algorithm and the shortest path algorithm was developed to solve this integrated planning problem. Computational experiments were completed to evaluate the performance of the proposed heuristic for different problem instances. At the end, conclusions are presented and future research …


An Integrated Network Modeling Framework For Analysis Of Multi-Line Order Pick Systems, Debjit Roy, Vishal Bansal Jan 2018

An Integrated Network Modeling Framework For Analysis Of Multi-Line Order Pick Systems, Debjit Roy, Vishal Bansal

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Due to demanding service levels in E-commerce order fulfillment, modeling and analysis of order picking processes in warehouses deserve special attention. With a particular focus on multi-line E-commerce orders, we develop modeling tools that are necessary to analyze the order consolidation delays in the downstream pick stations. We develop a queuing network modeling framework for integrated analysis of upstream (storage system) and downstream (pick system). We apply our modeling approach to an integrated order-pick system that includes a shuttle-based storage and retrieval system, and a single pick station. Using simulations, we test the effect of the storage system configuration on …


Managing The Order Picking Process In For Click And Collect In Grocery Stores, Dale T. Masel, Akhilesh Mesa Jan 2018

Managing The Order Picking Process In For Click And Collect In Grocery Stores, Dale T. Masel, Akhilesh Mesa

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Many grocery stores offering a service called “Click and Collect,” where customers can submit an order online and pick up the order at the store or have it delivered. To offer this service in an efficient way while still meeting customer expectations, stores can adapt methods used in warehouse order picking. Once strategy is the method used to group the orders into batches as they are received. We have examined two strategies for batching: order-based batching and time-based batching. From testing these two approaches, time-based batching produces a slightly lower average picking time, but order-based batching has orders ready for …


Deployment Of An Distributed Strategic Material Flow Control For Automated Material Flow Systems Consisting Of Autonomous Modules, Christian Lieberoth-Leden, Johannes Fottner Jan 2018

Deployment Of An Distributed Strategic Material Flow Control For Automated Material Flow Systems Consisting Of Autonomous Modules, Christian Lieberoth-Leden, Johannes Fottner

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

The modularisation of hardware and software is one approach to handle the demand for increasing flexibility and changeability of automated material flow systems that are, for example, utilised in flexible production systems. In such automated material flow systems, autonomous modules communicate with each other to coordinate and execute transport tasks. In this paper a strategic material flow control is introduced, which is distributed on several modules realised with a multi-agent system. The strategic material flow control agent coordinates transport tasks with advanced logistical requirements, such as sequencing. A transport task states for a transport unit the system source and sink …


Shuttle-Based Storage And Retrieval Systems With Robotic Order-Picking Shuttle Carrier, Tone Lerher Jan 2018

Shuttle-Based Storage And Retrieval Systems With Robotic Order-Picking Shuttle Carrier, Tone Lerher

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Shuttle-based storage and retrieval systems with robotic order picking shuttle carrier are relatively new systems not yet address in automated storage system research. The objective of this research paper is to propose analytical model for robotic order picking shuttle carriers. Analytical expressions for the calculation of multi cycle have been determined by assuming uniform distributed order-picking locations and the probability theory. The proposed model enables the calculation of the expected travel (cycle) time for multiple command cycles of the robotic order picking shuttle carrier, from which the throughput performance can be evaluated.


Optimization Of A Fast-Pick Area In A Cosmetics Distribution Center, Mario C. Velez-Gallego, Alice E. Smith Jan 2018

Optimization Of A Fast-Pick Area In A Cosmetics Distribution Center, Mario C. Velez-Gallego, Alice E. Smith

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Fast-pick areas are commonly used in order picking warehouses to improve labor efficiency by concentrating picking activities within a compact area, thus minimizing the distance traveled by the pickers. One problem that must be solved when a fast-pick area is to be implemented is the so-called assignment-allocation problem. This deals with deciding which products should be assigned to the fast-pick area, and how much space should be allocated to these products. This research was motivated by the picking operation of a cosmetics distribution center where several fast-pick areas are in place. A mixed integer linear programming formulation is proposed for …


Home Inventory Management And Last-Mile Logistics, Bhagyalakshmi V. Shrikrishna, Bharat Kulkarni, Michael G. Kay Jan 2018

Home Inventory Management And Last-Mile Logistics, Bhagyalakshmi V. Shrikrishna, Bharat Kulkarni, Michael G. Kay

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

A study of the functioning of last-mile logistics in home inventory management is described. Different patterns of the household consumptions are studied and assumed in the interim. These consumption patterns then form the automatic grocery ordering system leading to what we would refer as a “home inventory management system.” In the futuristic world. This paper focuses on the impact of driverless delivery vehicles and drone delivery to satisfy the demand of the customers in a future scenario where orders are placed automatically by a home inventory management system.


Pull-Driven Order Fulfillment In Distribution Centers, Dima Nazzal, Shankar Shanmugasundaram, Sung Kim, Russell D. Meller Jan 2018

Pull-Driven Order Fulfillment In Distribution Centers, Dima Nazzal, Shankar Shanmugasundaram, Sung Kim, Russell D. Meller

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

One of the challenges facing e-commerce fulfillment is the rigidity of the wave management system that often dictates a fixed batch size that must be processed before the next wave of orders is released. As a result, operation managers usually push multiple waves, which lead to accumulation at bottleneck resources, and poor synchronization at sortation engines. We demonstrate the power of operating an order fulfillment engine using the “pull” paradigm. We hypothesize that a pull-driven order fulfillment can meet the same throughput requirements achieved by the push-driven wave-based order fulfillment, but with higher speed, higher service levels, more level resource …


A Framework For Modeling Material Handling With Decentralized Control, Kai Furmans, Kevin R. Gue Jan 2018

A Framework For Modeling Material Handling With Decentralized Control, Kai Furmans, Kevin R. Gue

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Despite decades of research in material handling, the academic community still has no accepted way of describing material handling requirements in a way that machines and algorithms can process them. Such a “way of describing” requires a language with which to describe requirements, objects, relationships between objects, and so on. We propose a modeling framework that differs from existing research in two ways: First, we address material handling modeling from the bottom up rather than from the top down, meaning we define a set of elementary functions and then combine them into processes and more complex relationships that allow us …


Digital Design Of Intralogistics Systems: Flexible And Agile Solution To Short-Cyclic Fluctuations, Anike Murrenhoff, Christoph Pott, Moritz Wernecke, Philipp-Akira Burger Jan 2018

Digital Design Of Intralogistics Systems: Flexible And Agile Solution To Short-Cyclic Fluctuations, Anike Murrenhoff, Christoph Pott, Moritz Wernecke, Philipp-Akira Burger

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

In times of fast-paced, fluctuating and individual markets, intralogistics systems, such as warehouses, have to adapt to the resulting volatile performance demands dynamically. Hybrid systems, in which humans and machines work together efficiently and communicate in socio-technical networks, can be the answer to manage these high-frequency markets. Hybrid systems of the future need to adapt frequently and permanent change becomes the “new normal”. A one-time planning of warehousing systems upon first installation becomes obsolete. This results in the question of how to design and implement processes for future logistics systems in an agile way in order to exploit the flexibility …


Urban Parcel Logistics Hub And Network Design: The Impact Of Modularity And Hyperconnectivity, Benoit Montreuil, Shannon Buckley, Louis Faugere, Reem Khir, Shahab Derhami Jan 2018

Urban Parcel Logistics Hub And Network Design: The Impact Of Modularity And Hyperconnectivity, Benoit Montreuil, Shannon Buckley, Louis Faugere, Reem Khir, Shahab Derhami

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

This paper examines how exploiting the hyperconnectivity and modularity concepts underpinning the Physical Internet enables the parcel logistics industry to meet the worldwide challenges to efficiently and sustainably offer faster and more precise deliveries across urban agglomerations, notably across the world’s megacities. It emphasizes disruptive transformations of package logistics hubs and networks, such as multi-tier world pixelization, multi-plane parcel logistics web, smart dynamic parcel routing and hub-based consolidation, and modular parcel containerization.


Collaborative Bots In Distribution Centers, Russell D. Meller, Dima Nazzal, Lisa M. Thomas Jan 2018

Collaborative Bots In Distribution Centers, Russell D. Meller, Dima Nazzal, Lisa M. Thomas

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

This research investigates the business case for using autonomous collaborative robots (“bots”) in warehouses. Bots are designed to work collaboratively with human workers in warehouses to fill orders, primarily in e-commerce environments. In order-picking applications, a bot knows the location of every item in the warehouse, and when an item needs to be picked for an order, the bot navigates to that item and waits. Human workers are assigned to patrol specific zones, and when they see a bot waiting, the worker walks to the bot, reads the instructions off the screen, executes the task, and moves on. The bot …


Economic And Performance Analysis Of Dual-Bay Vertical Lift Modules, Fabio Sgarbossa, Martina Calzavara, Alessandro Persona Jan 2018

Economic And Performance Analysis Of Dual-Bay Vertical Lift Modules, Fabio Sgarbossa, Martina Calzavara, Alessandro Persona

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Warehouse picking is one of the most time and cost consuming activities in a warehouse, often requiring the presence of human operators, who travel within the aisles to retrieve the items needed by the customers. Several studies demonstrate that the travelling activity can represent even the 50% of the total picking time, with a subsequent creation of a separate storage and picking area for small objects. In the last years, new solutions for order picking systems have been developed, especially for small items. One of these solutions requires Vertical Lift Modules (VLMs), storage columns with extractable trays. In this paper, …


Dynamic Batching For Order Picking In Warehouses, Jelmer Pier Van Der Gaast, Bolor Jargalsaikhan, Kees Jan Roodbergen Jan 2018

Dynamic Batching For Order Picking In Warehouses, Jelmer Pier Van Der Gaast, Bolor Jargalsaikhan, Kees Jan Roodbergen

15th IMHRC Proceedings (Savannah, Georgia. USA – 2018)

Dynamic batch picking is characterized by combining product demand from multiple customer orders into one pick tour where new orders are continuously received. Using modern order-picking aids, updated picking instructions can be included in the current pick tours which allows pickers to be re-routed to pick for new orders even when they already started a pick tour. We develop a mathematical model for dynamic batch picking that minimizes the order throughput time of incoming customer orders. In case of new order arrivals, we can quickly re-optimize the model and determine new updated pick tours. This allows for short order throughput …


Fatal General Aviation Accidents In Furtherance Of Business (1996–2015): Rates, Risk Factors, And Accident Causes, Scott Burgess, Stewart Boyd, Douglas D. Boyd Jan 2018

Fatal General Aviation Accidents In Furtherance Of Business (1996–2015): Rates, Risk Factors, And Accident Causes, Scott Burgess, Stewart Boyd, Douglas D. Boyd

Publications

Introduction: General aviation missions related to furtherance of business potentially carry higher risk (operations in adverse weather, at night, for longer distances) than those undertaken for recreation. The study herein was undertaken to determine fatal accident rates, proportions, and risk factors/causes. Method: The National Transportation Safety Board aviation accident database was queried for accidents (1996–2015). Annual fleet times were from the general aviation annual activity survey. Statistical analyses used Poisson distributions, proportion testing, and Cohen’s Kappa tests. Results: The fatal accident rate for business operations was three- to six-fold lower than the rate for recreational flights with a decline evident …


Iact Undergraduate Certificate In Applied Creativity (Year 1 - 2018), Brian Laduca Jan 2018

Iact Undergraduate Certificate In Applied Creativity (Year 1 - 2018), Brian Laduca

IACT Certificate Program

At the Institute of Applied Creativity for Transformation (IACT) at ArtStreet, we seek to empower a creatively confident 21st-century student with the ability to discover, invent and innovate ambiguous ideas through a disruptive design process that will impact today’s ever-changing global world regardless of degree focus.

IACT is home to the nation’s first undergraduate certificate in Applied Creativity for Transformation. Open to undergraduate students of any major, the certificate is a first step in achieving the University of Dayton’s vision of innovation, applied creativity, entrepreneurship and community engagement for the common good.


Multivariate Analysis Of Students Perception On Teaching With Client Based And Non-Client Based Team Projects, Philip Appiah-Kubi Jan 2018

Multivariate Analysis Of Students Perception On Teaching With Client Based And Non-Client Based Team Projects, Philip Appiah-Kubi

Engineering Management and Systems Faculty Publications

The classroom experience has evolved from traditional lecture, PowerPoint and whiteboards to a more active environment where students and instructors work together on hands-on activities to achieve the course objectives. Various names have been given to this pedagogy; experiential learning, project based learning (client based versus non-client based), active learning, and problem based learning are a handful of names used to describe this evolving pedagogy. The main challenge faced by educators in educating undergraduate students to be independent thinkers and problem solvers has been the driving force fueling the shift in pedagogy. This research looks into student’s perception on project …


The Efficacy Of Financial Futures As A Hedging Tool In Electricity Markets, Jim Hanly, Lucia Morales, Damien Cassells Jan 2018

The Efficacy Of Financial Futures As A Hedging Tool In Electricity Markets, Jim Hanly, Lucia Morales, Damien Cassells

Articles

Abstract This paper estimates and applies a risk management strategy for electricity spot exposures using futures hedging. We apply our approach to three of the most actively traded European electricity markets, Nordpool, APXUK and Phelix. We compare both optimal hedging strategies and the hedging effectiveness of these markets for two hedging horizons, weekly and monthly using both Variance and Value at Risk (VaR). Our key finding is that electricity futures can effectively manage risk only for specific time periods when using hedging strategies that have been very successful in financial and other commodity markets. More generally they are ineffective as …