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Articles 901 - 930 of 1293

Full-Text Articles in Operations Research, Systems Engineering and Industrial Engineering

A Decision Theoretic Approach To Data Leakage Prevention, Janusz Marecki, Mudhakar Srivastava, Pradeep Reddy Varakantham Aug 2010

A Decision Theoretic Approach To Data Leakage Prevention, Janusz Marecki, Mudhakar Srivastava, Pradeep Reddy Varakantham

Research Collection School Of Computing and Information Systems

In both the commercial and defense sectors a compelling need is emerging for rapid, yet secure, dissemination of information. In this paper we address the threat of information leakage that often accompanies such information flows. We focus on domains with one information source (sender) and many information sinks (recipients) where: (i) sharing is mutually beneficial for the sender and the recipients, (ii) leaking a shared information is beneficial to the recipients but undesirable to the sender, and (iii) information sharing decisions of the sender are determined using imperfect monitoring of the (un)intended information leakage by the recipients.We make two key …


An Analysis Of Extreme Price Shocks And Illiquidity Among Systematic Trend Followers, Bernard Lee, Shih-Fen Cheng, Annie Koh Jun 2010

An Analysis Of Extreme Price Shocks And Illiquidity Among Systematic Trend Followers, Bernard Lee, Shih-Fen Cheng, Annie Koh

Research Collection Lee Kong Chian School Of Business

We construct an agent-based model to study the interplay between extreme price shocks and illiquidity in the presence of systematic traders known as trend followers. The agent-based approach is particularly attractive in modeling commodity markets because the approach allows for the explicit modeling of production, capacities, and storage constraints. Our study begins by using the price stream from a market simulation involving human participants and studies the behavior of various trend-following strategies, assuming initially that their participation will not impact the market. We notice an incremental deterioration in strategy performance as and when strategies deviate further and further from the …


Utilizing Knowledge Transfer To Promote Management Of Countervailing Risks In Value Stream Analysis, Jeffery A. Temple Apr 2010

Utilizing Knowledge Transfer To Promote Management Of Countervailing Risks In Value Stream Analysis, Jeffery A. Temple

Engineering Management & Systems Engineering Theses & Dissertations

Organizations are frequently faced with the challenges of modifying and streamlining their processes by utilizing the latest process improvement techniques such as Lean Thinking. They use these techniques to allow them to better perform their organizational purposes through the elimination of waste and non-value added steps. Personnel performing these modifications need to account for potential outcomes and risks when streamlining processes. An association of knowledge transfer and experience to the identification and handling of these countervailing or alternative risks when performing Lean Thinking value stream analysis is investigated. The elements of risk management, Lean Thinking and knowledge transfer are described. …


Gerber Project For Lockheed Martin, Andrew Callahan, Sean Lawyer Mar 2010

Gerber Project For Lockheed Martin, Andrew Callahan, Sean Lawyer

Industrial Technology and Packaging

Lockheed Martin, the world’s premier aerial combat vehicle manufacturer was pressed to find an eco-friendly way to package their impregnated epoxy. In the current system, the epoxy would be cut on the Gerber table to a pre-determined length and then sandwiched inside of two corrugated fiberboard sheets for storage inside of a freezer. The current process was not only labor intensive, but the corrugated fiberboard had to be disregarded after one use. In conjunction with the Cal Poly San Luis Obispo Packaging program and Melmat Incorporated, we were able to find a corrugated plastic substrate to replace the currently non-reusable …


An Analysis Of Extreme Price Shocks And Illiquidity Among Trend Followers, Bernard Lee, Shih-Fen Cheng, Annie Koh Feb 2010

An Analysis Of Extreme Price Shocks And Illiquidity Among Trend Followers, Bernard Lee, Shih-Fen Cheng, Annie Koh

Research Collection School Of Computing and Information Systems

We construct an agent-based model to study the interplay between extreme price shocks and illiquidity in the presence of systematic traders known as trend followers. The agent-based approach is particularly attractive in modeling commodity markets because the approach allows for the explicit modeling of production, capacities, and storage constraints. Our study begins by using the price stream from a market simulation involving human participants and studies the behavior of various trend-following strategies, assuming initially that their participation will not impact the market. We notice an incremental deterioration in strategy performance as and when strategies deviate further and further from the …


Practical Simulation Application: Evaluation Of Process Control Parameters In Twisted-Pair Cables Manufacturing System, Amr Mahfouz, Amr Arisha Jan 2010

Practical Simulation Application: Evaluation Of Process Control Parameters In Twisted-Pair Cables Manufacturing System, Amr Mahfouz, Amr Arisha

Articles

Intensive competition and rapid technology development of Twisted-Pair Cables (TPC) industry have left no room for competing manufacturers to harbour system inefficiencies. TPC are used in various communication and networks hardware applications; their manufacturing facilities face many challenges including various product configurations with different equipment settings, different product flows and Work in Process (WIP) space limitations. The quest for internal efficiency and external effectiveness forces companies to align their internal settings and resources with external requirements/orders, or in different words, significant factors must be set appropriately and identified prior to manufacturing processes. Integrated definition models (IDEF0, IDEF3) in conjunction with …


The Analysis Of Rush Orders Risk In Supply Chain: A Simulation Approach, Amr Arisha, Amr Mahfouz Jan 2010

The Analysis Of Rush Orders Risk In Supply Chain: A Simulation Approach, Amr Arisha, Amr Mahfouz

Conference papers

Satisfying customers by delivering demands at agreed time, with competitive prices, and in satisfactory quality level are crucial requirements for supply chain survival. Incident of risks in supply chain often causes sudden disruptions in the processes and consequently leads to customers losing their trust in a company’s competence. Rush orders are considered to be one of the main types of supply chain risks due to their negative impact on the overall performance. Using integrated definition modeling approaches (i.e. IDEF0 & IDEF3) and simulation modeling technique , a comprehensive integrated model has been developed to assess rush order risks and examine …


Risk And System-Of-Systems: Toward A Unified Concept, C. Ariel Pinto, Michael K. Mcshane, Rani Kady Jan 2010

Risk And System-Of-Systems: Toward A Unified Concept, C. Ariel Pinto, Michael K. Mcshane, Rani Kady

Engineering Management & Systems Engineering Faculty Publications

The scope of this paper is the survey of both fundamental and most recent publications in system-of-systems, business and insurance, as well as risk analysis, modeling, and management for the purpose of better describing the concept of risk in recognition of emergence and complexity which characterizes many systems within the concern of engineering and business managers. The ultimate goal is to provide engineering and business managers the necessary perspective on the concept of risk and in its management for the next generation of sustainable systems - including various descriptions of risk and discussion of the relevance of properties of system-of-systems …


Towards A Center For Modeling And Simulation: The Case For Jordan, Ghaith Rabadi, Hazem Kaylani, Joseph Barjis (Ed.), Murali Mohan Narasipuram (Ed.), Ghaith Rabadi (Ed.), Jolita Ralyt (Ed.), Pierluigi Plebani (Ed.) Jan 2010

Towards A Center For Modeling And Simulation: The Case For Jordan, Ghaith Rabadi, Hazem Kaylani, Joseph Barjis (Ed.), Murali Mohan Narasipuram (Ed.), Ghaith Rabadi (Ed.), Jolita Ralyt (Ed.), Pierluigi Plebani (Ed.)

Engineering Management & Systems Engineering Faculty Publications

Modeling and Simulation (M&S) has recently become an important area that is pursued by many researchers and practitioners due to the role it plays in understanding complex systems and problems. We have therefore witnessed the establishment of many M&S organizations in the last two decades especially in the more developed world. Less developed countries are starting to recognize the need for such capability especially that the problems they face are not less complex. In this paper, we present a preliminary study towards a business plan for establishing a scientific center for Modeling, Analysis, Simulation and Animation in Jordan (JoSAMA) and …


Accidents Will Happen. Do Safety Systems Improve Warehouse Safety Performance?, Rene B. M. De Koster, B. M. Balk, I Davelaar, M. Martens Jan 2010

Accidents Will Happen. Do Safety Systems Improve Warehouse Safety Performance?, Rene B. M. De Koster, B. M. Balk, I Davelaar, M. Martens

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Safety is becoming more and more an issue in warehouses. In the literature, effective measures leading to increased occupational health and safety have hardly been researched. Most research focuses on the impact of perceived safety-related leadership of managers and worker safety consciousness on ‘safety climate’ and workers’ safe behavior. We have carried out exploratory research into which measures really improve the safety performance of a warehouse. We particularly focus on the effects of (1) safety-related work procedures, (2) safety leadership, and (3) workers’ safety consciousness. Based on a survey we show that safety leadership and safety-related work procedures significantly drive …


Optimizing The Rearrangement Process In A Dedicated Warehouse, Hector J. Carlo, German E. Giraldo Jan 2010

Optimizing The Rearrangement Process In A Dedicated Warehouse, Hector J. Carlo, German E. Giraldo

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Determining the optimal storage assignment for products in a dedicated warehouse has been addressed extensively in the Facility Logistics literature. However, the process of implementing a particular storage assignment given the current location of products has not received much attention in the existing literature. Typically, warehouses use downtime or overtime to remove products from their current location and move them to the suggested location. This work presents the Rearrange-While-Working (RWW) policy to optimize the process of rearranging a dedicated warehouse. The RWW policy seeks to relocate products in a warehouse from the initial arrangement to the optimal arrangement while serving …


A New Milp Approach For The Facility Layout Design Problem With Rectangular And L/T Shaped Departments, Yossi Bukchin, Michal Tzur Jan 2010

A New Milp Approach For The Facility Layout Design Problem With Rectangular And L/T Shaped Departments, Yossi Bukchin, Michal Tzur

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

In this paper we propose a new approach for the facility layout problem (FLP) and suggest new mixed-integer linear programming (MILP) formulations. The proposed approach considers simultaneously the location of the departments within the facility and the internal arrangement of the machines. Two models are suggested, where the first addresses the rectangular department case and the second allows nonrectangular departments defined by an L/T shape. New regularity constraints are developed to avoid irregular department shapes.


Strategic Design Of A Robust Supply Chain, Marc Goetschalckx, Edward Huang Jan 2010

Strategic Design Of A Robust Supply Chain, Marc Goetschalckx, Edward Huang

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

The strategic design of a robust supply chain has as goal the configuration of the supply chain structure so that the performance of the supply chain remains of a consistently high quality for all possible future scenarios. We model this goal with an objective function that trades off the central tendency of the supply chain profit with the dispersion of the profit as measured by the standard deviation for any value of the weights assigned to the two components. However, the standard deviation, used as the dispersion penalty for profit maximization, has a square root expression which makes standard maximization …


Evaluating The Effect Of Operational Conditions And Practices On Warehouse Performance, Andrew L. Johnson Jan 2010

Evaluating The Effect Of Operational Conditions And Practices On Warehouse Performance, Andrew L. Johnson

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Analyzing warehouse performance across different environments is critical to improving overall productivity and reducing costs. Although two-stage DEA estimators have been shown to be statistically consistent, the finite sample bias of DEA in the first stage carries over to the secondstage regression, which causes bias in the estimated coefficients of the contextual variables. The bias is particularly severe when the contextual variables are correlated with inputs. To address this shortcoming, we apply insights from Johnson and Kuosmanen (2010), who demonstrate that DEA can be formulated as a constrained special case of the Convex Nonparametric Least Squares (CNLS) regression to develop …


Comparing Transport Policies In A Full-Scale 300mm Wafer Manufacturing Facility, J. E. Kiba, S. Dauz`Ere-P´Er`Es, C. Yugma, G. Lamiable Jan 2010

Comparing Transport Policies In A Full-Scale 300mm Wafer Manufacturing Facility, J. E. Kiba, S. Dauz`Ere-P´Er`Es, C. Yugma, G. Lamiable

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

Research in semiconductor manufacturing ideally wants to determine the “best” transport policy to ensure continuous production. Determining such a policy is difficult because it depends on many factors such as the layout, the product types, the equipment, etc. Most of the transport policies found in the literature combine dispatching policies (scheduling of transport requests) and routing policies (selection of the path to move from one point to another). This paper investigates a policy called "minimum service" which consists in keeping a minimum number of available vehicles in bays, so that they can quickly answer transport requests and empty travel times …


The Human-Centric Warehouse, Kevin R. Gue Jan 2010

The Human-Centric Warehouse, Kevin R. Gue

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

In theory and in practice, the objective of warehouse design has long been to meet operational requirements of throughput and service performance at minimum cost. A natural product of this “bottom line” approach has been warehouse buildings and operations ill-suited to the humans who spend their working lives interacting with them. We offer an explanation for the current approach, and argue that a new approach— a new paradigm —is needed. We then describe a comprehensive approach to warehouse design that includes human well-being as a primary goal.


Forklift Routing In Warehouses Using Dual-Commands And Stackable Pallets, Ahmed Hassan, Bill Ferrell Jan 2010

Forklift Routing In Warehouses Using Dual-Commands And Stackable Pallets, Ahmed Hassan, Bill Ferrell

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

This research determines time optimal routes for loading and picking pallets that can be stacked on top of each other during transport in a manual warehouse that only contains full pallets and utilizes single deep storage. This research was motivated by the fact that we are seeing this situation on an ever increasing basis, particularly in warehouses that supply parts to automotive assembly. In practice, forklift drivers have developed strategies to take advantage of this opportunity but to our knowledge there is no literature that addresses this problem rigorously. The important features of this work are that a time based …


Plug-And-Work Material Handling Systems, Kai Furmans, Frank Schonung, Kevin R. Gue Jan 2010

Plug-And-Work Material Handling Systems, Kai Furmans, Frank Schonung, Kevin R. Gue

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

One disadvantage of automated material handling systems is their relative Inflexibility: once racks are installed and conveyors are laid, making even mi-nor changes to a system can be cumbersome and expensive. However, recent progress in the capabilities and cost of basic system components, such as controllers, drives, and sensors, has made possible a new class of material handling systems having a much higher degree of flexibility. We propose underlying de- sign principles for such systems and describe several prototype plug-and-work" systems, which feature decentralized control and ease of reconfiguration.


Control Policies For A Dynamic Storage System With Multiple Lifts And Shuttles, Iris F.A. Vis, Hector J. Carlo, Paloma Diaz, Maria E. Laboy, Bruno Vanwijgaarden Jan 2010

Control Policies For A Dynamic Storage System With Multiple Lifts And Shuttles, Iris F.A. Vis, Hector J. Carlo, Paloma Diaz, Maria E. Laboy, Bruno Vanwijgaarden

11th IMHRC Proceedings (Milwaukee, Wisconsin. USA – 2010)

New types of Automated Storage and Retrieval Systems, able to achieve high throughput levels, are continuously being developed and require new control polices to take full advantage of the developed system. In this paper we study a dynamic storage system as developed by Vanderlande Industries consisting of a conveyor, two lifts, multiple transfer shuttles, and a storage rack. One of the decision problems for this system is the scheduling problem of the two lifts. In other words, which lift is going to handle which request and in which order. In this paper, we derive an integrated look-ahead heuristic based on …


Simulation Optimisation Methods In Supply Chain Applications: A Review, Amr Arisha, Waleed Abo-Hamad Jan 2010

Simulation Optimisation Methods In Supply Chain Applications: A Review, Amr Arisha, Waleed Abo-Hamad

Articles

The competitiveness and dynamic nature of today’s marketplace is due to rapid advances in information technology, short product life cycles and the continuing trend in global outsourcing. Managing the resulting supply chain networks effectively is challenged by high levels of uncertainty in supply and demand, confl ict objectives, vagueness of information, numerous decision variables and constraints. With such levels of complexity, supply chain optimisation has the potential to make a signifi cant contribution in resolving these challenges. In this paper, a literature review – based on more than 100 peer-reviewed articles – of state-of-the-art simulation-based optimisation techniques in the context …


Development Of A Framework To Evaluate Human Risk Towards Sustainable Risk Management, Ra'ed M. Jaradat, Rani A. Kady, C. Ariel Pinto Jan 2010

Development Of A Framework To Evaluate Human Risk Towards Sustainable Risk Management, Ra'ed M. Jaradat, Rani A. Kady, C. Ariel Pinto

Engineering Management & Systems Engineering Faculty Publications

Risk managers are constantly faced with the challenge of making decisions at various levels of their organizations. One of the challenges, which often times is unavoidable, lies in assigning a monetary value to human risks. Such challenge necessitates engineering managers to make educated decisions on the level of risk that the organizations and businesses should accept when it comes to human. The purpose of this study is to suggest a suitable framework that captures this aspect of engineering Risk Management in order to make rational and sustainable decisions about such assessed risk. This will be accomplished by exploring the tools, …


Utilizing Multimedia Case Studies To Teach The Professional Side Of Project Management, Cassandra C. Elrod, Susan L. Murray, Barry B. Flachsbart, Karl E. Burgher, Drew M. Foth Jan 2010

Utilizing Multimedia Case Studies To Teach The Professional Side Of Project Management, Cassandra C. Elrod, Susan L. Murray, Barry B. Flachsbart, Karl E. Burgher, Drew M. Foth

Business and Information Technology Faculty Research & Creative Works

This research was conducted to evaluate the effectiveness of using a LITEE multimedia case study to teaching concepts in engineering courses. The LITEE Superstar case study was implemented in an engineering Project Management course. Numerous surveys regarding student expectations, outcomes, and attitudes were collected and results are presented herein. Overall, the study provided evidence that the students felt that the LITEE case study added value to the course via the different methods of teaching material, aided in the understanding of the project selection process, and ultimately helped them be successful in their course project which was conducted for a real …


Project And Risk Management: A Systematic Approach, Baqer Alali, C. Ariel Pinto, Andreas Tolk, Rafael Landaeta Jan 2010

Project And Risk Management: A Systematic Approach, Baqer Alali, C. Ariel Pinto, Andreas Tolk, Rafael Landaeta

Engineering Management & Systems Engineering Faculty Publications

The main purpose of this paper is to discuss three related topics of project management, systems management, and risk management. The issue that would be addressed in this paper is how risks are addressed in project and systems management, and how risks are propagated between projects and systems. A framework is proposed to overcome the problem of risk propagation from project to the systems. It was shown that the proposed framework can be deployed to existing risk management process with reasonable interventions (e.g. process prescribed by PMI). Finally a proof-of-concept application shows potential of the framework for various types of …


The Impact Of Task Conflict On Virtual Team Performance And Cohesiveness, Wilawan Onkman, Anil Ustun, Pilar Pazos, Ana Maria Canto Jan 2010

The Impact Of Task Conflict On Virtual Team Performance And Cohesiveness, Wilawan Onkman, Anil Ustun, Pilar Pazos, Ana Maria Canto

Engineering Management & Systems Engineering Faculty Publications

This paper examined the impact of task conflict on team performance and cohesiveness. Twelve virtual teams participated in two sessions with two difficulty levels. Each task consisted of a survival simulation. Teams communicated using a text-based communication media (chat). A mixed methods approach combining both quantitative and qualitative data was used. Performance was measured using expert ratings, and cohesiveness was measured using a modified version of Seashore's Cohesiveness Index. Content analysis was utilized to evaluate the level of task conflict on the team. This study provides some initial evidence on the effects task conflict on virtual team performance.


Periodic Resource Reallocation In Two-Echelon Repairable Item Inventory Systems, Hoong Chuin Lau, Jie Pan, Huawei Song Jan 2010

Periodic Resource Reallocation In Two-Echelon Repairable Item Inventory Systems, Hoong Chuin Lau, Jie Pan, Huawei Song

Research Collection School Of Computing and Information Systems

Given an existing stock allocation in an inventory system, it is often necessary to perform reallocation over multiple time points to address inventory imbalance and maximize availability. In this paper, we focus on the situation where there are two opportunities to perform reallocation within a replenishment cycle. We derive a mathematical model to determine when and how to perform reallocation. Furthermore, we consider the extension of this model to the situation allowing an arbitrary number of reallocations. Experimental results show that the two-reallocation approach achieves better performance compared with the single-reallocation approach found in the literature. We also illustrate how …


Introducing Communication In Dis-Pomdps With Locality Of Interaction, Makoto Tasaki, Yuichi Yabu, Yuki Iwanari, Makoto Yokoo, Janusz Marecki, Pradeep Reddy Varakantham, Milind Tambe Jan 2010

Introducing Communication In Dis-Pomdps With Locality Of Interaction, Makoto Tasaki, Yuichi Yabu, Yuki Iwanari, Makoto Yokoo, Janusz Marecki, Pradeep Reddy Varakantham, Milind Tambe

Research Collection School Of Computing and Information Systems

The Networked Distributed POMDPs (ND-POMDPs) can model multiagent systems in uncertain domains and has begun to scale-up the number of agents. However, prior work in ND-POMDPs has failed to address communication. Without communication, the size of a local policy at each agent within the ND-POMDPs grows exponentially in the time horizon. To overcome this problem, we extend existing algorithms so that agents periodically communicate their observation and action histories with each other. After communication, agents can start from new synchronized belief state. Thus, we can avoid the exponential growth in the size of local policies at agents. Furthermore, we introduce …


Simulation Model To Investigate Flexible Workload Management For Healthcare And Servicescape Environment, Michael Thorwarth, Paul Harper, Amr Arisha Dec 2009

Simulation Model To Investigate Flexible Workload Management For Healthcare And Servicescape Environment, Michael Thorwarth, Paul Harper, Amr Arisha

Conference papers

High demand and poor staffing conditions cause avoidable pressure and stress among healthcare personnel which results in burnout symptoms and unplanned absenteeism which are hidden cost drivers. The work environment within an emergency department is commonly arranged in a flexible workload which is highly dynamic and complex for the outside observer. Using detailed simulation modeling within structured modeling methods, a comprehensive model to characterize the nurses' time utilization in such flexible dynamic workload environment was investigated. The results have been used to derive a generalized analytic expression that describes certain settings that lead to an instable queuing system with serious …


Simpler Packaging, Tomiko Oden Dec 2009

Simpler Packaging, Tomiko Oden

Graphic Communication

This project explains how product packaging is become more "green", and thus more simple. Packaging needs to go beyond just simplifying materials and graphics - it needs to create a simpler process in order to reduce wasted time, energy, and resources.


Measurement And Analysis Of Shocks To Products Packaged In Pails In Single Parcel Ground Shipments, Sher Paul Singh, Jay Singh, Pakapol Kittipinyovath Nov 2009

Measurement And Analysis Of Shocks To Products Packaged In Pails In Single Parcel Ground Shipments, Sher Paul Singh, Jay Singh, Pakapol Kittipinyovath

Industrial Technology and Packaging

The objective of this study was to measure and analyse the shocks and impacts experienced by pails in the single parcel distribution environment, with and without a secondary corrugated shipper. The study was conducted in the FedEx Ground shipping environment in the USA. Instrumented 5 gal pails were shipped with and without an outer corrugated box, and with and without handling (precautionary warning) labels, from East Lansing, Michigan to destinations in California and New York. Data recorders were used to collect and analyse shock distribution data (drop heights, drop orientations and number of drops). The results showed that the precautionary …


Sharing Mobile Multimedia Annotations To Support Inquiry-Based Learning Using Mobitop, Khasfariyati Razikin, Dion Hoe-Lian Goh, Yin-Leng Theng, Quang Minh Nguyen, Thi Nhu Quynh Kim, Ee Peng Lim, Chew-Hung Chang, Kalyani Chatterjea, Aixin Sun Oct 2009

Sharing Mobile Multimedia Annotations To Support Inquiry-Based Learning Using Mobitop, Khasfariyati Razikin, Dion Hoe-Lian Goh, Yin-Leng Theng, Quang Minh Nguyen, Thi Nhu Quynh Kim, Ee Peng Lim, Chew-Hung Chang, Kalyani Chatterjea, Aixin Sun

Research Collection School Of Computing and Information Systems

Mobile devices used in educational settings are usually employed within a collaborative learning activity in which learning takes place in the form of social interactions between team members while performing a shared task. We introduce MobiTOP (Mobile Tagging of Objects and People), a geospatial digital library system which allows users to contribute and share multimedia annotations via mobile devices. A key feature of MobiTOP that is well suited for collaborative learning is that annotations are hierarchical, allowing annotations to be annotated by other users to an arbitrary depth. A group of student-teachers involved in an inquiry-based learning activity in geography …