1,720,964 research outputs found
Monitour: Tracking global routes of electronic waste
No full textMany nations seek to control or prevent the inflow of waste electronic and electrical equipment, but such flows are difficult to track due to undocumented, often illegal global trade in e-waste. We apply wireless GPS location trackers to this problem, detecting potential cases of non-compliant recycling operations in the United States as well as the global trajectories of exported e-waste. By planting hidden trackers inside discarded computer monitors and printers, we tracked dozens of devices being sent overseas to various ports in Asia, flows likely unreported in official trade data. We discuss how location tracking enables new ways to monitor, regulate, and enforce rules on the international movement of hazardous electronic waste materials, and the limitations of such methods.
Perspectives on semantics of the place from online resources
No full textWe present a methodology for extraction of semantic indexes related to a given geo-referenced place. These lists of words correspond to the concepts that should be semantically related to that place, according to a number of perspectives. Each perspective is provided by a different online resource, namely upcoming.org, Flickr, Wikipedia or open Web search (using Yahoo! search engine). We describe the process by which those lists are obtained, present experimental results and discuss the strengths and weaknesses of the methodology and of each perspective
MIT GEOblog: a platform for digital annotation of space for collective community based digital story telling
No full textThis paper focuses on guidelines in designing platforms for collective, location-sensitive user generated content, built upon a system that allows for locating mobile subjects within the space. The process of conceptual design, design development, and technical implementation of MIT GEOblog project from a user-interaction design point of view, is used to illustrate the applicability of the guidelines. GEOblog is a web-based platform that allows people to annotate the space, through geo-tagging and sharing user generated content or, in other words, placing digital content over spatial zones that can be retrieved by others based on their real-time sensed location by the system
Tracking Trash
Get PDFUsing active self-reporting tags, the authors followed 2,000 objects through Seattle's waste management system. By making the waste "removal chain" more transparent, they help reveal the disposal process of everyday objects, highlighting potential inefficiencies in the current removal system.Waste ManagementQUALCOMM Inc.Sprint Corp.Architectural League of New YorkCity of SeattleSENSEable City Laboratory Consortiu
Understanding individual and collective mobility patterns from smart card records: A case study in Shenzhen
No full textUnderstanding the dynamics of the inhabitants' daily mobility patterns is essential for the planning and management of urban facilities and services. In this paper, novel aspects of human mobility patterns are investigated by means of smart card data. Using extensive smart card records resolved in both time and space, we study the mean collective spatial and temporal mobility patterns at large scales and reveal the regularity of these patterns. We also investigate patterns of travel behavior at the individual level and show that the concentricity and regularity of mobility patterns. The analytical methodologies to spatially and temporally quantify, visualize, and examine urban mobility patterns developed in this paper could provide decision support for transport planning and management
Taxi-Aware Map: Identifying and Predicting Vacant Taxis in the City
Get PDFKnowing where vacant taxis are and will be at a given time and location helps the users in daily planning and scheduling, as well as the taxi service providers in dispatching. In this paper, we present a predictive model for the number of vacant taxis in a given area based on time of the day, day of the week, and weather condition. The history is used to build the prior probability distributions for our inference engine, which is based on the naïve Bayesian classifier with developed error-based learning algorithm and method for detecting adequacy of historical data using mutual information. Based on 150 taxis in Lisbon, Portugal, we are able to predict for each hour with the overall error rate of 0.8 taxis per 1x1 km[superscript 2] area.Volkswagen of America. Electronic Research LabAT&T FoundationNational Science Foundation (U.S.)MIT-Portugal ProgramSENSEable City Laboratory Consortiu
Putting Matter in Place: Measuring Tradeoffs in Waste Disposal and Recycling
No full textProblem, research strategy, and findings: Reliable information on trash disposal is crucial but becomes difficult as waste removal chains grow increasingly complex. Lack of firm data on the spatial behavior of waste hampers effective recycling strategy design. In particular, the environmental impact of electronic and household hazardous waste is poorly understood. Our study investigates waste processing in an environmental, economic, and geographic context, using novel methods to track municipal solid waste in the city of Seattle (WA). We observed the movement of 2,000 discarded items using attached active GPS sensors, recording an unprecedented spatial dataset of waste trajectories. We both qualitatively identified facilities visited along each item's trajectory, then statistical modeled characteristic transportation distance and the likelihood of ending up at a specific type of facility by product categories, place of disposal, and collection mechanism. We show that a) electronic and household hazardous waste items travel significantly longer and have more arbitrary trajectories than other types of waste and b) that existing models for waste emissions may underestimate the environmental impact of transportation by not accounting for very long trajectories.
Takeaway for practice: Transportation costs and emissions may diminish the value of recycling. Collection strategies deserve closer attention given the long distances over which they operate. Electronic tracking could provide data for evaluating waste management systems
A holistic framework for the study of urban traces and the profiling of urban processes and dynamics
No full textPervasive systems produce massive amounts of data as by-products of their interaction with users. Cell phone calls can inform us on how many people are present in a given area and how many are entering or leaving it. Geotagged photos can tell us where tourists go within the city and how much time they spend in each place. Descriptions of events, products, and services allow us to characterize places based on their most popular activities, products, and services. In this paper we illustrate a research agenda that aims at developing a holistic framework for the study of urban traces and the profiling of urban processes and their dynamics which will enable us to better understand how cities function and to develop more efficient urban policies. We also present the results of a preliminary case study in New York City where we analyzed the correlation between cell phone network handovers and traffic volumes and between semantic indexes of public events and local variations in cell phone activity. The results showed that there exist causal relationships between these types of data, and confirmed that there is strong promise in the holistic study of urban traces
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
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