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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.
61

Implications of Advanced Technologies on Rural Delivery

Kaplan, Marcella Mina 24 May 2024 (has links)
This dissertation integrates the strengths of individual emergent delivery technologies with package characteristics, and rural community needs to meet the demand for equitable, accessible, and inclusive rural delivery that is also cost-effective. To find ways to meet the package delivery service needs in rural areas and to fill research gaps in rural package delivery modeling, this study introduced a novel model known as the Parallel Scheduling Vehicle Routing Problem (PSVRP) in an endeavor to revolutionize package delivery by enhancing its efficiency, accessibility, and cost-effectiveness. The PSVRP represents a state-of-the-art approach to vehicle routing problems, incorporating a diversified fleet of innovative delivery modes. The multi-modal fleet of electric vans, ADVs, drones, and truck-drone systems works in unison to minimize operational costs in various settings. A solution methodology that implemented the Adaptive Large Neighborhood Search (ALNS) algorithm was designed to solve the PSVRP in this research to produce optimal or near-optimal solutions. A variety of scenarios in a rural setting that include different quantities of customers to deliver to and different package weights are tested to evaluate if a multi-modal fleet of electric vans, ADVs, drones, and truck-drone systems can provide cost-effective, low emissions, and efficient rural delivery services from local stores. Different fleet combinations are compared to demonstrate the best combined fleet for rural package delivery. It was found that implementation of electric vans, ADVs, drones, and truck-drone systems does decrease rural package delivery cost, but it does not yet decrease cost enough for the return on investment to be high enough for industry to implement the technology. Additionally, it was found that electric technologies do significantly decrease emissions of package delivery in rural areas. However, without a carbon tax or regulation mandating reduced carbon emissions, it is unlikely that the delivery industry will quickly embrace these new delivery modes. This dissertation not only advances academic understanding and practical applications in vehicle routing problems but also contributes to social equity by researching methods to improve delivery services in underserved rural communities. The PSVRP model could benefit transportation professionals considering technology-enabled rural delivery, developing rural delivery plans, looking for cost-effective rural delivery solutions, implementing a heterogeneous fleet to optimize rural delivery, or planning to reduce rural delivery emissions. It is anticipated that these innovations will spur further research and investment into rural delivery optimization, fostering a more inclusive and accessible package delivery service landscape. / Doctor of Philosophy / This dissertation integrates the strengths of individual emergent delivery technologies with package characteristics, and rural community needs to meet the demand for equitable, accessible, and inclusive rural delivery that is also cost-effective. To find ways to meet the package delivery service needs in rural areas and to fill research gaps in rural package delivery modeling, this study introduced a novel model known as the Parallel Scheduling Vehicle Routing Problem (PSVRP) in an endeavor to revolutionize package delivery by enhancing its efficiency, accessibility, and cost-effectiveness. The PSVRP represents a state-of-the-art approach to vehicle routing problems, incorporating a diversified fleet of innovative delivery modes. The multi-modal fleet of electric vans, ADVs, drones, and truck-drone systems works in unison to minimize operational costs in various settings. A solution methodology that implemented the Adaptive Large Neighborhood Search (ALNS) algorithm was designed to solve the PSVRP in this research to produce optimal or near-optimal solutions. A variety of scenarios in a rural setting that include different quantities of customers to deliver to and different package weights are tested to evaluate if a multi-modal fleet of electric vans, ADVs, drones, and truck-drone systems can provide cost-effective, low emissions, and efficient rural delivery services from local stores. Different fleet combinations are compared to demonstrate the best combined fleet for rural package delivery. It was found that implementation of electric vans, ADVs, drones, and truck-drone systems does decrease rural package delivery cost, but it does not yet decrease cost enough for the return on investment to be high enough for industry to implement the technology. Additionally, it was found that electric technologies do significantly decrease emissions of package delivery in rural areas. However, without a carbon tax or regulation mandating reduced carbon emissions, it is unlikely that the delivery industry will quickly embrace these new delivery modes. This dissertation not only advances academic understanding and practical applications in vehicle routing problems but also contributes to social equity by researching methods to improve delivery services in underserved rural communities. The PSVRP model could benefit transportation professionals considering technology-enabled rural delivery, developing rural delivery plans, looking for cost-effective rural delivery solutions, implementing a heterogeneous fleet to optimize rural delivery, or planning to reduce rural delivery emissions. It is anticipated that these innovations will spur further research and investment into rural delivery optimization, fostering a more inclusive and accessible package delivery service landscape.
62

新世代電信級網路電話(VoIP)客戶服務之研究 / The study of customer service for carrier grade next generation network (VoIP)

徐志得, Hsu, Heigen Unknown Date (has links)
在電信獨占市場的時代,語音及訊務都架設在TDM (時間分割多工)的系統上,其客戶服務比新世代網路系統較為簡易。1997年,政府開放行動電話營運執照申請,在2008年第一季末,手機門號(包含2G+PHS+3G)幾乎與人口(2300萬戶)ㄧ樣多。2000年,政府開放固網執照申請,因為固網路鋪設到last-mile的速度緩慢及成本較高,「新進業者」(CLEC)比「既有經營者」(ILEC)較不具備競爭力,加上無killer application (殺手級應用)及差異性的客服,因此至今CLEC沒有爭取到太多的顧客,一直到Skype進入台灣,大家才看到電信語音市場另一塊新版圖。 近年來VoIP (Voice Over IP)技術進步,將通訊協定信號(SIP)與媒體語音訊務(RTP/RTCP)分開處理。因此,全世界各通信製造業者及服務商(SP)開始運用此技術在行動電話多媒體服務及IP多媒體子系統(IMS)的架構上。不僅如此,有很多網路用戶與互聯網企業也因為開始分享資訊,造成一些新興內容產業--(UGC用戶產生內容、SNS社會網絡服務) 的誕生。所以預料在新世代電信網路(NGN)新科技的環境之下,將會有不少新興產業如海星組織一般的誕生、滋長及蔓延,這對電信業者、服務供應商及用戶將會帶來更多維護及服務的衝擊。 因此本研究將參考現有電信客戶服務跟未來20年通信技術,建議如何使用混合式(集權/分權)的客戶服務來協助電信級固網業者及服務開發者去創造企業價值、突破現有困境、達到永續經營的目的,以因應未來電信自由化及新電信技術。 / In the monopoly era, the telecom network was implemented on TDM (Time Division Multiplexer) system, whose customer service of voice call is comparatively simpler and easier than NGN (Next Generation Network) system. In 1997, government opened the application of mobile network operation license. By end of 1Q of 2008, the subscriber count (includes 2G, PHS and 3G) of mobile network was almost as many as population (23 millions). In the year of 2000, government opened the application of fixed network operation license. Because of the slower speed and higher cost of last-mile network implementation, up to now, new Competitive Local Exchange Carriers (CLEC) were less competitive than Incumbent Local Exchange Carrier (ILEC). Plus, not having the killer-application and the differentiated customer services, CLECs did not have too many subscribers in these years. Until Skype was introduced to Taiwan, all of us, then, saw the other new territory of voice telecom market. These years, VoIP (Voice over IP) technology was improved to have communication protocol (SIP Session Initialization Protocol) and voice traffic (RTP/RTCP Real-time Transport Protocol/Real-time Transport Control Protocol) been handled separately; i.e., the development of voice application software and debug became easier. Thus, the world-wide telecom manufacturers and service providers started to use this technology on the architecture of mobile voice multimedia service and IP Multi-media Subsystem (IMS). Even amount of network users were sharing information with enterprises who owned inter-connection network, and created the new content businesses (UGC User Generated Content, SNS Social Network Services). Therefore, under the new technology environment of NGN, we foresee some new businesses will be created, then, growing and expanding like the starfish organization. For telecom operators, service providers and users, this will bring some more new impacts of maintenance and service. Therefore, this study will refer the existing telecom customer service and the telecom technologies may have in next coming 20 years to propose how to use the hybrid (centralized/de-centralized) customer service to help both carrier-grade fixed network operators and service developers to create business value, break through current dilemma to reach business continuity goal in response to the telecom liberalization and new telecom technologies.
63

The role of ICT in optimizing reverse textile supply chains

Tsiupka, Iuliia, Mason, Alicia January 2015 (has links)
Fast fashion and over consumption within the textile industry has led to a serious depletion of natural resources. The current rate of population growth and consumption is unsustainable. In result, there is a growing interested in sustainable solutions, one of which is reverse supply chains. Infrastructures for recycling textile fibers are being researched and developed. At the same time, it is important to put a focus on also developing the infrastructures for textile recollection. When examining a forward supply chain, the last mile, or point of distribution to the final consumer, can be considered the most costly when it comes to logistics costs. As a result, within a reverse supply chain the point of textile recollection, or the “first mile” as defined by the authors, can also be considered problematic in terms of logistical costs. Cirqle is a Swedish based app using ICT to aide in the recollection of used textiles, by offering app users rewards (discounts) for used textile returns at specific retailers. Through gathering specific information about app users, ICT companies such as Cirqle, are key to optimizing reverse supply chains, and in result, aiding in the reduction of the “first mile problem”. Due to the research gap identified by the authors, the purpose of this thesis is to explore how a digital infrastructure for collecting used garments, such as the Cirqle App, can be used to optimize location‟s for collection points; therefore minimizing the first mile problem of reverse logistics in the textile industry.
64

Circuit and System Design for mm-wave Radar and Radio Applications

Sarkas, Ioannis 13 August 2013 (has links)
Recent advancements in silicon technology have paved the way for the development of integrated transceivers operating well inside the mm-wave frequency range (30 - 300 GHz). This band offers opportunities for new applications such as remote sensing, short range radar, active imaging and multi-Gb/s radios. This thesis presents new ideas at the circuit and system level for a variety of such applications, up to 145 GHz and in both state-of-the-art nanoscale CMOS and SiGe BiCMOS technologies. After reviewing the theory of operation behind linear and power amplifiers, a purely digital, scalable solution for power amplification that takes advantage of the significant ft/fmax improvement in pFETs as a result of strain engineering in nanoscale CMOS is presented. The proposed Class-D power amplifier, features a stacked, cascode CMOS inverter output stage, which facilitates high voltage operation while employing only thin-oxide devices in a 45 nm SOI CMOS process. Next, a single-chip, 70-80 GHz wireless transceiver for last-mile point-to-point links is described. The transceiver was fabricated in a 130 nm SiGe BiCMOS technology and can operate at data rates in excess of 18 Gbps. The high bitrate is accomplished by taking advantage of the ample bandwidth available at the W-band frequency range, as well as by employing a direct QPSK modulator, which eliminates the need for separate upconversion and power amplification. Lastly, the system and circuit level implementation of a mm-wave precision distance and velocity sensor at 122 and 145 GHz is presented. Both systems feature a heterodyne architecture to mitigate the receiver 1/f noise, as well as self-test and calibration capabilities along with simple packaging techniques to reduce the overall system cost.
65

Circuit and System Design for mm-wave Radar and Radio Applications

Sarkas, Ioannis 13 August 2013 (has links)
Recent advancements in silicon technology have paved the way for the development of integrated transceivers operating well inside the mm-wave frequency range (30 - 300 GHz). This band offers opportunities for new applications such as remote sensing, short range radar, active imaging and multi-Gb/s radios. This thesis presents new ideas at the circuit and system level for a variety of such applications, up to 145 GHz and in both state-of-the-art nanoscale CMOS and SiGe BiCMOS technologies. After reviewing the theory of operation behind linear and power amplifiers, a purely digital, scalable solution for power amplification that takes advantage of the significant ft/fmax improvement in pFETs as a result of strain engineering in nanoscale CMOS is presented. The proposed Class-D power amplifier, features a stacked, cascode CMOS inverter output stage, which facilitates high voltage operation while employing only thin-oxide devices in a 45 nm SOI CMOS process. Next, a single-chip, 70-80 GHz wireless transceiver for last-mile point-to-point links is described. The transceiver was fabricated in a 130 nm SiGe BiCMOS technology and can operate at data rates in excess of 18 Gbps. The high bitrate is accomplished by taking advantage of the ample bandwidth available at the W-band frequency range, as well as by employing a direct QPSK modulator, which eliminates the need for separate upconversion and power amplification. Lastly, the system and circuit level implementation of a mm-wave precision distance and velocity sensor at 122 and 145 GHz is presented. Both systems feature a heterodyne architecture to mitigate the receiver 1/f noise, as well as self-test and calibration capabilities along with simple packaging techniques to reduce the overall system cost.
66

Nouvelles organisations de la distribution urbaine des colis sur le dernier kilomètre : innover par une approche spatiale / Structuring last-mile parcel delivery solutions for urban zones : an innovative spatial approach for urban goods distribution

Ducret, Raphaëlle 19 December 2014 (has links)
Le contexte technologique et socioéconomique favorise la croissance des volumes de colis échangés en France et particulièrement l'augmentation des livraisons dans les villes. Livraisons qui se complexifient sous l'effet des contraintes urbaines, des injonctions de durabilité, des évolutions des attentes des clients. Les prestataires de la distribution urbaine de colis doivent relever les défis économiques, organisationnels, environnementaux et politiques que représente cette mutation de la distribution du dernier kilomètre. Replacer la ville et son organisation spatiale au centre de la création de nouvelles organisations de la distribution et rapprocher l'analyse spatiale des outils et des techniques de gestion du transport de marchandises en ville (TMV), et notamment de la modélisation, peut permettre d'innover. La thèse va développer cette posture, jusque-là délaissée par les recherches en TMV. Une analyse détaillée de la nature des relations entre forme urbaine, organisations spatiale et TMV va être proposée. A partir de ces résultats, les premiers éléments d'une modélisation spatiale du TMV au service de la création d'un outil d'aide à la décision capable de segmenter la ville en zones différenciées en fonction de leurs caractéristiques spatiales, socioéconomiques et politiques et d'adapter les solutions de livraison par zones seront proposés. / With the spread of new technologies and the advent of economic and social changes, the volume of parcels has grown in France. Parcel deliveries in cities have similarly experienced an important increase. Deliveries have become more and more complex because of changing client patterns, urban constraints and cities' concerns for sustainability. The growing complexity of the ‘last mile' delivery poses economic, organizational, environmental and political challenges to parcel providers. Putting the spatial organization of cities back at the heart of the creation of new logistics organizations and integrating spatial studies to urban logistics techniques and tools, in particular in modelling, can be means of innovation. Until now spatial studies have been largely under-used in UF. This study will provide an in-depth analysis of the relationships between urban spatial organization, urban form and UF. Based on those results, the thesis provides the first elements of a spatial urban freight modelling approach. The modelling approach will enable the creation of a decision support tool able to identify homogeneous urban zones based on urban form, economic and political characteristics in order to offer the most suitable delivery solution to each zone of a city.
67

A systematic literature review on drones’ application in last-mile delivery.

Persson, Emil January 2021 (has links)
In recent years, companies such as Amazon and DHL have started to develop alternative last-mile delivery options because of the growing trend in e-commerce. Last-mile deliveries refer to the terminal to customer deliveries and have become increasingly challenging to manage, as traffic congestions in cities has risen. Therefore, companies have begun searching for alternative delivery methods, such as autonomous drones or unmanned aerial vehicles (UAV). The purpose of this thesis is to investigate drones in the current literature on last-mile delivery. First, by conducting a systematic literature review on the current literature available in two major databases. Second, by analyzing the collected literature sample and presenting it through a descriptive analysis focusing on bibliometrics and a thematic analysis that identifies emerging themes for drivers for drones’ application in last-mile delivery, barriers for drones’ application in last-mile delivery, and approaches for implementing drones in last-mile delivery.                        Drones’ application in last-mile delivery has the potential to reduce cost, decrease delivery time, reduce emissions, and reduce energy consumption. However, barriers that hinder the implementation, such as governmental regulations, need further consideration for the implementation to occur. Some evident gaps can be found related to the barriers. Both managers and researchers might find the thesis useful, as it provides a holistic view on the subject, with theoretical, managerial, and societal implications being presented.
68

Hållbarhet – en prioritering hos e-handelskonsumenter? : En studie om konsumenters beteende vid valet av hållbara leveransalternativ. / Sustainability – a priority among e-commerce consumers? : A study of consumers behavior when choosing sustainable delivery options.

Eskilstorp, Johanna, Holmqvist, Madeleine January 2021 (has links)
Syftet med studien är att undersöka vilka faktorer som påverkar konsumenternas val av leveransalternativ och varför dessa blir avgörande i konsumenternas sista milen val. Enligt tidigare forskning är sista milen leveranserna e-handelns minst hållbara del men som samtidigt också har störst potential att förändras till att bli mer hållbar. Något som kan ske genom olika påverkansfaktorer vilket kan få konsumenter att välja hållbart. En mix av kvalitativa metoder används vilken innehåller tre olika delstudier - skrivbordsstudie, semistrukturerade intervjuer och fokusgrupper. Studien genomförs inom e-handelsområdet i Sverige. Resultatet visar att ett antal faktorer blir avgörande för konsumenternas hållbara val i SML, varav kunskap och information ses som den främsta bristen vilken måste förbättras. Resultatet visar även på motstridigheter mellan teori, företag och konsumenter. Studien visar då på att konsumenterna inte besitter den hållbarhetsprioriteringen som teorin påstår. Detsamma gäller för företagen där endast 20 företag av de 100 främsta e-handelsföretagen i Sverige erbjuder ett hållbart leveransalternativ i SML. Det framgår ur studien att det krävs mer, tydligare och lättförståddinformation kring hållbarheten i SML. Däremot behöver denna information kommuniceras före, under och efter konsumentens köp. / The purpose of the study is to examine which factors influence consumers’ choice of delivery alternatives and why these factors become decisive in consumer’ last mile choices. According to previous research, last mile deliveries are the least sustainable part of the e-commerce, but at the same time also have the greatest potential to become more sustainable. That can happen through various influencing factors which can get consumers to make sustainable choices. A mix of qualitative methods is used, which contains three different sub-studies - a desktop study, semi-structured interviews and focus groups. The study is carried out in the e-commerce business area in Sweden. Our findings reveal that a number of factors is decisive for consumers’ sustainable choices in SML, of which knowledge and information is seen as the main factor which must be improved. The findings also show contradictions between the theory, the companies and the consumers. The consumers do not possess the priority of sustainability that the theory claims they have. The same applies to the companies where only 20 companies out of the top 100 in the Swedish e-commerce offer a sustainable delivery alternative in SML. The study shows that more, clearer and information that is easier to understand regarding the sustainability of SML is required. On the contrary, this information needs to be communicated before, during and after the consumer's purchase. This thesis is written in Swedish.
69

Digitala och tekniska lösningar inom sista mil-leveranser : En studie om hur leveransföretag kan bemöta konsumenters krav på sista mil-leveranser / Digital and technical solutions within last mile deliveries : A study of how delivery companies can meet consumers' demands for last-mile deliveries

Sörbom, Josefine, Bjurlemark, Adelaide January 2020 (has links)
E-commerce is in a growing phase where consumers are getting more aware, picky and comfortable when it comes to delivery of their packages. This case study investigates the requirements that consumers have regarding last-mile deliveries as well as various digital logistic solutions that may meet these requirements. In the study, relevant people in three different companies working with delivery, have been selected to get a deeper insight into how companies view consumers' new requirements and how they work to meet these and how they reflect about the future when it comes to last-mile deliveries. Consumers now expect a faster and more flexible service where they can design the last-mile delivery according to their premises, e.g. time, location,  etc. The demands emerging associated with the expansion of e-commerce include faster, cheaper and more flexible deliveries. Transparency in environmental issues and work processes has also become an important factor for many consumers today, which may be decisive for purchasing power. Collaboration with other actors enables e-commerce companies to streamline their delivery alternatives in the form of outsourcing. This approach can be done through collaboration with other logistics players or in the form of crowdsourcing. The term E-logistics implies a system that contains various parts of a logistic process in which the exchange takes place with both the help of technology and the internet. In combination with a functioning digital infrastructure and e-logistics, delivery processes can become more effective. New technologies such as parcel locks, drones and delivery robots are being analyzed as potential solutions to streamline last-mile deliveries. / E-handeln befinner sig i en växande fas där konsumenterna är allt mer medvetna, kräsna ochbekväma. Denna fallstudie undersöker de krav som konsumenter har kring sista-milen leveransersamt olika digitala logistiklösningar som kan komma att möta dessa krav. I studien har ävenrelevanta personer, i tre olika organisationer som arbetar med leverans, valts ut för att få en djupareinblick på hur företag ser på konsumenters nya krav. Studien undersöker hur de arbetar för attmöta dessa samt hur det ser på framtiden när det kommer till sista mil-leveranser. Konsumenternaförväntar sig nu mer flexibla och snabba leveranser där de själva får utforma sista mil-leveranserefter deras premisser. Kraven som växt fram i takt med den växande e-handeln är bland annatsnabbare, billigare och mer flexibla leveranser. Transparens inom miljöfrågor och arbetsprocesserhar även blivit en viktig faktor för många konsumenterna idag som kan komma att bli avgörandeför konsumentens köpvillighet. Samarbete med andra aktörer möjliggör för e-handelsföretag atteffektivisera sina leveransalternativ i form av outsourcing. Tillvägagångssättet kan ske genomsamarbete med andra logistikaktörer eller i form av privatpersoner, crowdsourcing. E-logistik ärdet system som innehåller olika delar i en logistikprocess där utbytet sker med hjälp av teknik ochinternet. I kombination av en fungerande digital infrastruktur och e-logistik så kanleveransprocesser effektiviseras. Ny teknik som paketlås, drönare och leveransrobot analyserassom potentiella leveransmedel för att effektivisera sista mil-leveranser.
70

Rapid transformation and inertia in planning and e-commerce : A qualitative study about e-commerce and planning in Sweden

Hultgren, Viktoria January 2022 (has links)
This thesis investigates the rapid transformation of e-commerce innovation in relation to planning intention inertia. This research explores the development of e-commerce prior to the Covid-19 pandemic effects and during, in relation to authority’s recognition of the development. The thesis also explores consumers’ reasons and choices for purchasing products through e-commerce. Furthermore, it explores last mile delivery solutions and logistics, together with future aspects and collaborations. Qualitative methodology is applied in the thesis involving semi-structured interviews with ten respondents from nine organisations, conversation analysis from a digital event in the form of one moderator and four attendees and content analysis from five documents and reports. The theoretical approach involves theories on diffusion and technological change and planning intention inertia together with collective action.

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