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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

The impact of and solutions to electronic and electrical waste management in Hong Kong SAR

Zhang, Chan 01 January 2010 (has links)
No description available.
42

Dietary exposure, human body loadings, and health risk assessment of persistent organic pollutants at two major electronic waste recycling sites in China

Chan, Kit Yan 01 January 2008 (has links)
No description available.
43

Environmental fingerprints and biological effects of dioxins, with reference to the electronic waste recycling site at Guiyu

Yu, Chik Kin 01 January 2008 (has links)
No description available.
44

Ecotoxicological quality assessment of sediments in Guiyu, an electronic waste disposal site in Southeast China

Wang, Fang 01 January 2007 (has links)
No description available.
45

GC/ion trap MS method development and applications for the analysis of polybrominated diphenyl ethers in environmental and biota samples

Luo, Qian 01 January 2008 (has links)
No description available.
46

Assessment and bioremediation of solis contaminated by uncontrolled recycling of electronic-waste at Guiyu, SE China

Yu, Xiezhi 01 January 2008 (has links)
No description available.
47

EVOLUTION OF SMARTPHONES METAL CONTENT WITH ITS FAST-IMPROVING FUNCTIONALITIES

Omar N Tantawi (9187403) 31 July 2020 (has links)
<p>Smartphones, one of the most common consumer electronic devices, are an essential part of daily activities in modern society. Smartphones provide faster communication, easier access to information and many other important services. However, with a compressed product life cycle and growing consumer demand, a significant number of smartphones reach End-of-Life (EoL) annually. At the same time, due to many special physical properties, rare earth, critical and other important metals are essential for the manufacturing of smartphones. Hence, from various economic, resources availability and environmental perspectives, it is crucial to understand how metal content of different smartphones generations change over time. To this end, a high production smartphone series, produced between 2010 and 2015 were considered in the scope of this study. The devices were disassembled, sorted into different components and size reduced. Printed circuit boards assembly, back cameras and NFC antenna/wireless charging chips were then digested using a novel microwave assisted acid digestion method. Inductively Coupled Plasma-Optical Emission Spectroscopy was used to detect and quantify 60 elements. Obtained results indicate that up to 70% of different smartphones components by weight are important recyclable metals. The highest concentration elements, Cu, Ni, Sn, Zn and Fe, accounted for 93.3% while REEs and PGMs collectively accounted for 0.53% of the total recoverable elements by weight. In 2019, the total addressable market value of metals reclamation from only three smartphone components at their end of life is estimated at 298.69 million USD in USA. Gold and Platinum were determined to be the most environmentally critical elements and efforts should made to reduce their use. Finally, and most importantly, smartphones manufacturers should design their products with an extended lifetime due to the high concentration of critical elements used to make them.</p>
48

An Applied Anthropology of Electronic Waste in Central Australia

Gideon A Singer (9031820) 26 June 2020 (has links)
<p>As an applied anthropology study of electronic waste (e-waste) in the remote town of Alice Springs, this dissertation chronicles how e-waste is understood and managed in the arid interior of Australia. What is electronic waste? ‘Electronic’ refers to the presence and movement of electricity throughout an object so that it may perform some expected function. Waste, however, defies simple definition. Waste usually refers to something that has been discarded due to being unwanted or unusable.<br></p><p><br></p> <p>This dissertation traces and tracks the boundaries of e-waste in Central Australia using ethnographic methods, anthropological theories of waste, and digital garbology. Digital garbology, a synthesis of digital anthropology and garbology, helps to identify and recommend strategies for confronting uneven, and often unjust, distributions of e-waste. Rather than focusing solely on discarded consumer electronics, this dissertation takes a critical look into the different types of waste emerging from the production, use, maintenance, and discard of electronics.</p><p><br></p> <p>Over the course of thirteen months of fieldwork in Alice Springs, it became clear that the label e-waste is not consistently applied to discarded electronics. E-waste is often discarded in out-of-sight locations such as landfills, recycling centers, and illegal dumping grounds. Before being discarded, however, unused electronics are often stored inside homes, sheds, and other living spaces. Rather than simply focusing on electronic objects that have already been thrown away, this dissertation explores how and why some electronics seem to resist being labeled as e-waste.</p><p><br></p> <p>Why Alice Springs? The management of e-waste in Australia has focused on the recovery of valuable metals from the recycling of televisions, computers, and mobile phones at the expense of other discarded electronics such as solar panels and household appliances. And yet, the closest e-waste recycling facility to Alice Springs is over 1,500 kilometres (900 miles) away in Adelaide, South Australia. The remoteness of Alice Springs reduces the ecological benefits of recycling. However, it also creates room to discuss the viability of alternative e-waste management strategies such as reuse and repair.</p>
49

RF Wireless Power Transfer for IoT Applications

Tavana, Morteza January 2022 (has links)
With the emergence of the Internet of things (IoT) networks, the replacement of batteries for IoT devices became challenging. In particular, the battery replacement is more expensive and cumbersome for scenarios where there are many IoT devices; or where the IoT devices are in unreachable locations; or when they have to be replaced often. Some IoT devices might be lost or forgotten, and there is a risk of hazardous chemicals leakage and e-waste in large scale in nature. Radio frequency (RF) wireless power transfer (WPT) is an alternative technology for powering those devices. It has been shown that only less than one millionth of the transmitted energy is absorbed by the receivers, the rest is absorbed by the objects in the environment. We can utilize the existing infrastructure for wireless communications such as base stations (BS) to charge IoT devices. The present work is devoted to analyze the feasibility and limitations of the battery-less operation of IoT devices with RF WPT technology and energy harvesting from existing infrastructure for wireless communications. We study the indoor and outdoor scenarios for powering of IoT devices. In the first scenario, we consider an outdoor environment where an IoT device periodically harvests energy from an existing BS and transmits a data packet related to the sensor measurement under shadow fading channel conditions. We analyze the limits (e.g., coverage range) of energy harvesting from a BS for powering IoT devices. We characterize the "epsilon-coverage range, where" is the probability of the coverage. Our analysis shows a tradeoff between the coverage range and the rate of sensor measurements, where the maximal "epsilon-coverage range is achieved as the sensor measurement rate approaches zero. We demonstrate that the summation of the sleep power consumption and the harvesting sensitivity power of an IoT device limits the maximal "epsilon-coverage range. Beyond that range, the IoT device cannot harvest enough energy to operate. The desired rate of the sensor measurements also significantly impacts the "epsilon-coverage range. We also compare the operational domain in terms of the range and measurement rate for the WPT and battery-powered technologies. In the second scenario, we consider the remote powering of IoT devices inside an aircraft. Sensors currently deployed on board have wired connectivity, which increases weight and maintenance costs for aircraft. Removing cables for wireless communications of sensors on board alleviates the cost, however, the powering of sensors becomes a challenge inside aircraft. We assume that the IoT devices have fixed and known locations inside an aircraft. The design problem is to minimize the number of WPT transmitters given constraints based on the cabin geometry and duty cycle of the IoT devices. We formulate a robust optimization problem to address the WPT system design under channel uncertainties. We also derive an equivalent integer linear programming and solve that for an optimal deployment to satisfy the duty cycle requirements of the cabin sensors. / <p>QC 20220223</p><p></p>
50

Informal Electronic Waste Recycling in Pakistan

Umair, Shakila January 2015 (has links)
The aim of this thesis was to study governance aspects of informal electronic waste recycling and to provide better knowledge of the business in terms of structure, stakeholders, governance aspects and social impacts. The thesis consists of a cover essay and two papers appended at the end of the thesis. The cover essay summarizes the papers and puts them in context. The objective of Paper I is to study the business of informal electronic waste recycling in Pakistan and highlight its governance issues. Paper II assesses the social impacts of this business using UNEP-SETAC Guidelines. The thesis examines these specific questions: Q1) What is the current situation of informal e-waste recycling in Pakistan? Q2) Who are the important stakeholders and what are their roles in this business? Q3) What are the governance issues enabling this informal business? Q4) What are the social impacts for individuals and society arising from this business? Paper I presents the international and local e-waste flows, business structure, the stakeholders involved and the existing governance issues of the business. It shows weak enforcement of legislation, the complexities emerging with numerous stakeholders, the profitability of informal recycling, little concern for the health damaging exposure for workers from poorest and most vulnerable people in society, and the lack of awareness of the hazards involved results in several governance issues. The paper also highlights how this business lacks characteristics of good governance, which makes it a challenge to control this business. Paper II assesses the social impacts of informal e-waste recycling in Pakistan using UNEP/SETAC guidelines for conducting a Social Lifecycle Analysis (SLCA). It showed that this business has positive impacts relating to societal issues and individual/family economics, and in the economic development of Pakistan but otherwise most impacts were negative. The findings of Paper II fill an important data gap and can be integrated with data on other stages of ICT product lifecycle to produce a full SLCA of such products. / Syftet med denna avhandling var att studera styrningsaspekter informella återvinning elektroniskt avfall och för att ge bättre kunskap om verksamheten i fråga om struktur, intressenter, styrningsaspekter och sociala konsekvenser. Avhandlingen består av en täck uppsats och två tidningar bifogade i slutet av uppsatsen. Locket uppsats samman tidningarna och sätter dem i sitt sammanhang. Syftet med papper I är att studera verksamheten i informella återvinning elektroniskt avfall i Pakistan och belysa dess styrningsfrågor. Papper II bedömer de sociala konsekvenserna av denna verksamhet med hjälp av UNEP-SETAC riktlinjer. Avhandlingen undersöker dessa specifika frågor: Q1) Vad är den nuvarande situationen för informella återvinnings e-avfall i Pakistan? Q2) Vilka är de viktigaste intressenterna och vilka är deras roller i den här branschen? Q3) Vilka styrningsfrågor som möjliggör denna informella företag? Q4) Vilka är de sociala konsekvenserna för enskilda och samhället som följer av detta företag? Papper I presenterar internationella och lokala e-avfallsflöden, företagsstruktur, de inblandade aktörerna och de befintliga styrningsfrågor i verksamheten. Det visar en svag tillämpning av lagstiftningen, komplexiteten växande med många intressenter, lönsamheten för informella återvinning, lite oro för hälsan skadliga exponering för arbetstagare från de fattigaste och mest utsatta människorna i samhället, och bristen på medvetenhet om de risker inblandade resultaten i flera styrningsfrågor. Papperet belyser också hur denna verksamhet saknar egenskaper för god förvaltning, vilket gör det till en utmaning att styra denna verksamhet. Papper II bedömer de sociala konsekvenserna av informella återvinnings e-avfall i Pakistan använder UNEP / SETAC riktlinjer för att genomföra en social livscykelanalys (SLCA). Det visade sig att denna verksamhet har positiva effekter avseende samhällsfrågor och individ / familj ekonomi, och i den ekonomiska utvecklingen i Pakistan men annars de flesta effekterna var negativa. Resultaten av pappers II fyller ett viktigt tomrum uppgifter och kan integreras med uppgifter om andra stadier av IKT produktlivscykeln för att producera en full SLCA av sådana produkter. / <p>QC 20150525</p>

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