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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.
141

Community Perception of Gunplay inModern FPS games : within Call of Duty: Warzone and Rainbow Six: Siege

McCabe, Andrew January 2023 (has links)
This study aims to look at multiple modern first person shooter games communitiesto see how their perception of gunplay may be similar or differ from one another.The study uses Toh’s (2016) model for players' feelings towards their primaryweapons to form a questionnaire, the questionnaire is based upon previous researchwithin appraisal theory, player goals , and players feelings. The questionnaire wasthen sent out to Apex Legends, Call of Duty: Warzone and Rainbow Six: Siegecommunities to gather their perception of weapon attributes and their effects onplayers. After analysis of the data similarities and differences were found withinspecific weapon attributes that showed how the communities valued variousweapon attributes. Call of Duty: Warzone focused more on lowering time to kill, whileRainbow Six: Siege focused more on being able to accurately breach and hold offenemies in close engagments. Using background research a possible way to showgame developers how to increase a player's play time from the data collected is alsodiscussed. With the help of an acafen approach a discussion on possibilities as towhy the games have different values and preferences is also had.
142

Truck electrification : Trends and impacts on the energy system

NORDHAMMER, CAROLINE, GRANKVIST, JESSICA January 2021 (has links)
In line with the Paris agreement, Sweden has set up a national emission reduction target for the transport sector; to reduce the emissions by 70% by 2030, relative to levels in 2010. This entails that large shares of road transport will be electrified, including shares of the national truck fleet. In parallel with this, the Swedish transmission grid suffers from power capacity shortages, limiting the amount of electricity that can be distributed to a regional and local level, especially in urban areas, such as Stockholm. In line with this, the aim of this thesis is to investigate the trends of truck electrification in the Stockholm region and to assess its potential impact on the electrical grid based on truck operation characteristics. To achieve this, three objectives were set; to investigate truck fleet operators’ operations and view in relation to electrification, examine truck manufacturers' views on truck electrification and to analyse the truck electrification’s potential impact on the electrical grid in future scenarios. Quantitative and qualitative methods were used to fulfil the research objectives including interviews and casestudy modelling. The results from the interviews show that both manufacturers and truck fleet operators see the electrical grid and deployment of charging infrastructure, as well as the economy of the electric truck as the main barriers to overcome in relation to truck electrification. The truck manufacturers have taken on a leading role and are together with early adopters pushing the development forward. Nonetheless, they cannot create all the right conditions themselves, as for instance charging opportunities in relation to the electric grid is a complex problem. The industry agreed upon that city transports will be electrified first followed by regional transport and lastly long-distance transport. Furthermore, 2030 was identified as a key year for truck electrification. Finally, manufacturers and truck fleet operators urge the government to act and implement necessary measures to support the transition. The results from the case-study modelling show that lunchtime charging of city transport coincides with already critical hours for the electrical grid. Moreover, the afternoon charging of city, regional and long-distance transports generates a peak during the most critical hour around 6 PM, implying that it could entail challenges for an already congested grid. In line with this, proper night-time charging is considered as crucial both from an operational (in terms of minimising the daily stops) and grid point of view (in terms of avoiding grid congestion during critical hours). In addition, it is recommended to prioritise charging of long-distance transport during the day as they often are operative around-the-clock. Although this study resulted in general charging profiles, this gives a good indication on what impact the truck electrification might have on the electrical grid. Furthermore, it gives a general picture of how the electrification of trucks could play out in Stockholm, which can be applied in other urban areas in Sweden that are facing similar challenges. / I linje med Parisavtalet har Sverige satt upp nationella utsläpps reduktionsmål för transportsektorn; att reducera utsläppen med 70% till 2030, relativt nivåerna 2010. Detta medför att stora delar av transportsektorn kommer att elektrifieras, inklusive stora delar av den nationella lastbilsflottan. Parallellt med detta lider det svenska transmissionsnätet av kapacitetsbrist vilket begränsar mängden elektricitet som kan överföras till en regional och lokal nivå, speciellt i urbana områden såsom Stockholm. I linje med detta har syftet med denna studie varit att undersöka trender inom lastbils-elektrifiering i Stockholmsregionen och att utvärdera dess potentiella inverkan på elnätet baserat på lastbilars operativa mönster. För att uppnå detta sattes tre mål upp; att undersöka lastbils-operatörers verksamhets mönster och deras syn på elektrifiering, att undersöka lastbilstillverkares syn på elektrifiering och att analysera lastbils-elektrifieringens potentiella inverkan på energisystemet i framtida scenarier. Kvantitativa och kvalitativa metoder användes för att uppnå studiens mål inklusive; intervjuer och fallstudie modellering. Resultaten från intervjuerna visar att både lastbils-operatörer och tillverkare ser elnätet och utbredningen av laddinfrastruktur, såväl som totalekonomin av den elektriska lastbilen som de huvudsakliga barriärerna att överkomma vid en elektrifiering. Lastbilstillverkare har tagit en ledande roll och driver utvecklingen av elektriska lastbilar framåt med hjälp av så kallade early adopters. Däremot kan de inte skapa alla förutsättningar själva då till exempel laddnings möjligheter i relation till elnätet är en komplex fråga. Industrin är eniga om att city transporter kommer att elektrifieras först, följt av regionala och till sist fjärrtransporter. Vidare kunde 2030 identifieras som ett nyckelår för elektrifieringen. Slutligen uppmanar både tillverkare och lastbils operatörer regeringen att implementera nödvändiga åtgärder för att stötta och påskynda omställningen. Resultaten från modelleringen i fallstudien visar att lunch-laddning för city transporter sammanfaller med redan kritiska timmar för elnätet. Dessutom genererar eftermiddagsladdningen av city, regionala och fjärrtransporter, en effekttopp runt klockan 18 vilket skulle kunna medföra utmaningar för ett redan överbelastat elnät. I linje med detta anses natt-laddning vara avgörande både från en operativ synpunkt (i form av att minimera de dagliga stoppen) och från ett elnäts perspektiv (i form av att undvika överbelastning av nätet under redan kritiska timmar). Därtill, rekommenderas att fjärrtransporter prioriteras för dagtids-laddning då de ofta är operative dygnet runt. Trots att denna studie resulterade i generella ladd-profiler kan dessa ge en god indikation för vilken inverkan lastbils-elektrifieringen kan komma att ha på elnätet. Vidare, ger studien en generell bild över hur lastbils-elektrifieringen kan komma att se ut i Stockholmsregionen vilket kan tillämpas i andra urbana områden i Sverige som står inför liknande utmaningar.
143

The impact of the automotive trade agreement between Canada and the United States

Arnold, Samuel January 1969 (has links)
Note:
144

The admissibility of evidence in tariff classification for customs duty / Daniel Hendrik Wijnbeek

Wijnbeek, Daniel Hendrik January 2014 (has links)
Customs duty represents an inescapable financial obligation in international trade. Such duties are determined by valuing the imported goods according to the classification of the goods. To classify the goods under an appropriate tariff heading is notoriously difficult – despite the almost trite principles from judicial decisions amongst the jurisdictions discussed in this study, such as the European Union, Australia, Canada and the United States of America. In South Africa, the Customs and Excise Act 91 of 1964 defines the ambit of customs duties and ratifies the Harmonised System ("HS"). The HS allows for a uniform approach to tariff classification used by countries across the world accounting for in excess of 95% of the world trade. Countries that employ this system are obliged to incorporate the HS into such country's domestic legislation and to use all headings and subheadings of the HS without addition or alteration, together with the numerical codes and to apply the General Rules for Interpretation and all section, chapter and subheading notes. Classification of goods is to be done objectively at the time of presentation of the goods to the tax authorities. The intentions of the importer or the descriptions of the goods in advertisements and manuals constitute inadmissible evidence. In the recent judgment of Smith Mining Equipment (Pty) Ltd v The Commissioner: South African Revenue Service1 ("Smith Mining") the court, however, opined that it was not obliged to consider the notes referred to above, in the absence of evidence on use of the specific vehicles at the different locations allowed for in the Tariff Headings. The Court expected the importer to present evidence on use and relied on evidence from the manual, whilst it ignored the evidence that the importer presented structured along the applicable tariff notes. The court's approach clamped on the Additional Rules in the USA and the more liberal approach applied in Canada, but stands in conflict with the approach in the European Union and the trite principles from the South African case law. / LLM (Import and Export Law), North-West University, Potchefstroom Campus, 2015
145

The admissibility of evidence in tariff classification for customs duty / Daniel Hendrik Wijnbeek

Wijnbeek, Daniel Hendrik January 2014 (has links)
Customs duty represents an inescapable financial obligation in international trade. Such duties are determined by valuing the imported goods according to the classification of the goods. To classify the goods under an appropriate tariff heading is notoriously difficult – despite the almost trite principles from judicial decisions amongst the jurisdictions discussed in this study, such as the European Union, Australia, Canada and the United States of America. In South Africa, the Customs and Excise Act 91 of 1964 defines the ambit of customs duties and ratifies the Harmonised System ("HS"). The HS allows for a uniform approach to tariff classification used by countries across the world accounting for in excess of 95% of the world trade. Countries that employ this system are obliged to incorporate the HS into such country's domestic legislation and to use all headings and subheadings of the HS without addition or alteration, together with the numerical codes and to apply the General Rules for Interpretation and all section, chapter and subheading notes. Classification of goods is to be done objectively at the time of presentation of the goods to the tax authorities. The intentions of the importer or the descriptions of the goods in advertisements and manuals constitute inadmissible evidence. In the recent judgment of Smith Mining Equipment (Pty) Ltd v The Commissioner: South African Revenue Service1 ("Smith Mining") the court, however, opined that it was not obliged to consider the notes referred to above, in the absence of evidence on use of the specific vehicles at the different locations allowed for in the Tariff Headings. The Court expected the importer to present evidence on use and relied on evidence from the manual, whilst it ignored the evidence that the importer presented structured along the applicable tariff notes. The court's approach clamped on the Additional Rules in the USA and the more liberal approach applied in Canada, but stands in conflict with the approach in the European Union and the trite principles from the South African case law. / LLM (Import and Export Law), North-West University, Potchefstroom Campus, 2015
146

Förvaltningsmyndigheternas kommunikationsskyldighet : Regelverk och tillämpning / The duty of administrative authorities to communicate : Regulations and application

Pavon, Christian January 2015 (has links)
This essay deals with the principle of communication as phrased in section 17 of the Swedish administrative act. According to this section administrative authorities are obliged to inform a party involved in an administrative case of all material which has been added to the case by somebody else and is of importance for the decision and then give the party an opportunity to comment on it. The purpose of this essay is to examine how courts evaluate the way administrative authorities apply this rule. How do the authorities fail in their obligation to communicate and what do the courts say about this? The essay includes a description of the details of the law and what preparatory work and doctrine say about it. The essay includes an analysis of thirteen court cases. The courts were critical of the application of the rule in a majority of cases. The analysis showed different kinds of deviations from the obligation to communicate. The courts only accepted minor deviations. In most cases where the authorities had failed in their communication the courts reversed the decisions. The conclusion of the analysis is that the courts are very strict when they evaluate how administrative authorities apply their obligation to communicate. / I inledningen till denna uppsats görs en liknelse mellan det som kallas kommunikationsprincipen och boken Processen av Franz Kafka där huvudpersonen upplever motsatsen till allt det som denna princip innebär. Uppsatsen behandlar kommunikationsskyldigheten som den regleras i 17 § förvaltningslagen. Det är en skyldighet som förvaltningsmyndigheter har gentemot enskilda och som är mycket viktig för rättssäkerheten och allmänhetens förtroende för myndigheter. En enskild kan vara inblandad i ett ärende hos en förvaltningsmyndighet. Det kan till exempel handla om att en person söker bygglov eller att en person som äger en restaurang riskerar att få sitt serveringstillstånd indraget. I alla sådana ärenden som innebär myndighetsutövning mot enskild måste myndigheten informera den som är part i ärendet om alla de uppgifter som tillförts ärendet av någon annan än honom/henne själv och som har betydelse för utgången i ärendet. Det kan handla om muntliga eller skriftliga uppgifter, uppgifter som tillförts ärendet inifrån eller utifrån myndigheten. Parten ska också ges tillfälle att komma med synpunkter på dessa uppgifter. Den enskilda individen ska inte själv behöva undersöka om nya uppgifter kommit in. Det är myndighetens ansvar att se till att den enskilda får dessa uppgifter.   Syftet med denna uppsats är att undersöka hur domstolarna bedömer att förvaltningsmyndigheterna tillämpar denna regel. Vilka brister finns i myndigheternas tillämpning av sin kommunikationsskyldighet och hur bedömer domstolarna dessa brister? Vad beror bristerna på?   För att undersöka detta analyserades totalt 13 rättsfall. Där förekom olika typer av brister i kommunikationen, muntliga yttranden från t.ex  arbetsgivarrepresentanter i tjänstetillsättningsärenden kommunicerades inte. I ett par fall informerade myndigheterna inte om uppgifter de själva tillfört ärendet. Orsakerna till bristerna kunde förutom försummelse och bristande rutiner vara feltolkningar av lagen. I ett par fall kunde man misstänka att myndigheterna avsiktligt avstod att meddela vissa uppgifter. Domstolarna godtog bara mycket små avvikelser från kommunikationsskyldigheten. I de allra flesta av fallen bedömde domstolarna att bristerna var så allvarliga att besluten upphävdes och återförvisades till lägre instans för ny bedömning Analysen visar att domstolarna är mycket stränga i sin bedömning av förvaltningsmyndigheternas tillämpning av regeln om kommunikationsskyldighet.
147

Design and analysis of MAC protocols for wireless multi-hop sensor and terahertz networks

Lin, Jian 27 May 2016 (has links)
The contributions of this thesis include designing and analyzing novel medium access control (MAC) protocols for two types of wireless networks: (1) duty-cycling cooperative multi-hop wireless sensor networks (MHWSNs), and (2) single-hop Terahertz networks (TeraNets). For MHWSNs, the specific contributions are two new scalable MAC protocols for alleviating the “energy-hole” problem with cooperative transmission (CT). The energy-hole is known to limit the life of battery-powered MHWSNs. The hole occurs when nodes near the Sink exhaust their energy first because their load is heavier: they must transmit packets they originate and relay packets from and to other nodes farther from the Sink. Effective techniques for extending lifetime in MHWSNs include duty cycling (DC) and, more recently introduced, cooperative transmission (CT) range extension. However, a scalable MAC protocol has not been presented that combines both. From the MAC perspective, conducting CT in an asynchronous duty-cycling network is extremely challenging. On the one hand, the source, the cooperators and the destination need to reach consensus about a wake-up period, during which CT can be performed. This dissertation develops novel MAC protocols that solve the challenge and enable CT in an asynchronous duty-cycling network. On the other hand, the question arises, “Does the energy cost of the MAC cancel out the lifetime benefits of CT range extension?” We show that CT still gives as much as 200% increase in lifetime, in spite of the MAC overhead. The second contribution of this dissertation is a comprehensive analytical framework for MHWSNs. The network performance of a MHWSN is a complex function of the traffic volume, routing protocol, MAC technique, and sensors' harvested energy if sensors are energy-harvesting (EH) enabled. The optimum performance provides a benchmark for heuristic routing and MAC protocols. However, there does not exist such an optimization framework that is able to capture all of these protocol aspects. The problems and performance metrics of non-EH networks and EH networks are different. Because the non-EH nodes depend on a battery, a suitable performance metric is the lifetime, defined as the number of packets delivered upon the first or a portion of nodes' death. Thus, the lifetime is governed by the absorbing states in a controlled dynamic system with finite decision horizon. On the other hand, the lifetime of an EH network is theoretically infinite unless the sensors are broken or destroyed. Therefore, an infinite horizon problem is formulated towards the performance of EH networks. The proposed model departs significantly from past analyses for single-hop networks that do not capture routing and past analyses for multi-hop networks that miss MAC aspects. To our knowledge, this is the first work to model the optimal performance of MHWSNs, by jointly considering MAC layer link admission, routing queuing, energy evolution, and cooperative transmission. The third contribution of this dissertation is a novel MAC protocol for Terahertz (THz) Band wireless networks, which captures the peculiarities of the THz channel and takes advantage of large antenna arrays with fast beam steering capabilities. Communication in THz Band (0.1-10THz) is envisioned as a key wireless technology in the next decade to provide Terabits-per-second links, however, the enabling technology is still in its infancy. Existing MAC protocols designed for classical wireless networks that provide Megabits-per-second to Gigabits-per-second do not scale to THz networks, because they do not capture the peculiarities of the THz Band, e.g., the very high molecular absorption loss or the very high reflection loss at THz Band frequencies. In addition, to overcome the high path loss and extend communication range, the proposed MAC design takes advantage of fast beam steering capabilities provided by the large antenna arrays, in particular, beam-switching at the pulse level.
148

An assessment of the effectiveness of management review as an ISO 14001:2004 continual improvement element : an Eskom distribution case study / Nokhuthala Deligence Hlongwana

Hlongwana, Nokhuthala Deligence January 2014 (has links)
Eskom Holdings SOC Limited (referred to as Eskom), a public state owned company, is required to continually demonstrate environmental duty of care and report on its environmental performance. In furthering its commitment to sustainable development and in line with environmental compliance of its activities, Eskom is planning to have the Distribution Division certified against the International Organisation for Standardization (ISO) 14001:2004 environmental management system (EMS) standard by 2014. In general, management review may quickly turn into a dry review of the items on the agenda, done only to show an auditor the review was held. As such, the aim of this study was to assess the effectiveness of management reviews as one of the key continual improvement elements of the ISO 14001:2004 environmental management system within Eskom Distribution: Western Region. This research has been designed to take place in three stages. These stages are planning, execution and publication, and preparing the dissertation for marking. The research methodology included a literature study on various national and international articles and journals on EMSs that relate to environmental performance. The databases of Eskom Distribution: Western Region ‒ i.e. the management review presentation results for the 2008/09, 2009/10 and 2010/11 financial years, key significant environmental aspects for the Technical Service Centres (TSCs) and Minor/Major Engineering Works (MEW), key performance indicators (KPIs), Risk Audit System (RAS) results, and results of the external EMS audit conducted from 23–25 April 2007 were used for this research. Questionnaires were sent to the TSCs’ senior supervisors and Safety, Health, Environment and Quality (SHEQ) management. An analysis of the questionnaires completed by the TSC senior supervisors showed that all the participants have seen an improvement in environmental performance due to annual management reviews, except TSC11, who have not seen management review results. It can be concluded from the results of the SHEQ management questionnaires that an improvement (continual improvement as per the ISO 14001 requirement) was observed. The improvements were identified through improved processes, improved gap analysis, increased environmental awareness, and addressing risks. Most of the ISO 14001:2004 requirements for the management review for all financial years covered in this study were met. In terms of the objectives, targets and KPIs, Eskom Distribution: Western Region performed effectively and most of the outcomes were implemented according to the recommendations. Further, based on the external audit conducted from 23 to 25 April 2007, it is clear that Eskom Distribution: Western Region conformed to the minimum requirements of the ISO 14001:2004 EMS. Their management reviews also met all requirements of the ISO 14001:2004 relating to management review. This was proven by minutes of previous meetings that covered all the necessary issues that were audited. Thus, the existence of management reviews contributed towards ensuring that the ISO system was scrutinised and improved where it worked, and that aspects that did not work well were removed. / M. Environmental Management, North-West University, Potchefstroom Campus, 2014
149

'n Onderwysregtelike perspektief op die sorgsame toesighoudingsplig van die Suid-Afrikaanse opvoeder / Lodewikus Stephanus Herselman

Herselman, Lodewikus Stephanus January 2006 (has links)
According to legislation, common law and case law, South African educators have a responsibility to ensure the safety of learners. Above all, God has placed children in our care and it is our God-given duty to take care of them. For educators to be able to perform this duty of care as it should be, they need to be equipped with the necessary legal knowledge. However, the acquisition of this knowledge remains the primary responsibility of each educator. Other educational role-players also have some moral obligation and responsibility to assist educators in attaining such knowledge. As educators should acquaint themselves with the relevant legislation regarding duty of care, such legislation should be accessible to all educators. Principals should encourage educators to become acquainted with the content of the relevant education laws. All the determinants regarding duty of care ought to be general knowledge to educators. Principles such as what torts comprise of, the requirements of delictual accountability, reasonable foreseeability and preventability and the reasonable educator test should be as well-known as subject didactical knowledge. Real-life situations and case law should be used to ensure a clear understanding of these principles. Tendencies in international law should also be communicated to educators. This study determined that educators do not have sound legal knowledge to meet the minimum requirements set by legislation, common law and case law. Tertiary institutions will have to compile training programs urgently so that education departments, trade unions, governing bodies and principals can make it available to educators, who, in turn can empower themselves with relevant, practical education law knowledge. / Thesis (M.Ed.)--North-West University, Potchefstroom Campus, 2006.
150

Congestion and medium access control in 6LoWPAN WSN

Michopoulos, Vasilis January 2012 (has links)
In computer networks, congestion is a condition in which one or more egressinterfaces are offered more packets than are forwarded at any given instant [1]. In wireless sensor networks, congestion can cause a number of problems including packet loss, lower throughput and poor energy efficiency. These problems can potentially result in a reduced deployment lifetime and underperforming applications. Moreover, idle radio listening is a major source of energy consumption therefore low-power wireless devices must keep their radio transceivers off to maximise their battery lifetime. In order to minimise energy consumption and thus maximise the lifetime of wireless sensor networks, the research community has made significant efforts towards power saving medium access control protocols with Radio Duty Cycling. However, careful study of previous work reveals that radio duty cycle schemes are often neglected during the design and evaluation of congestion control algorithms. This thesis argues that the presence (or lack) of radio duty cycle can drastically influence the performance of congestion control mechanisms. To investigate if previous findings regarding congestion control are still applicable in IPv6 over low power wireless personal area and duty cycling networks; some of the most commonly used congestion detection algorithms are evaluated through simulations. The research aims to develop duty cycle aware congestion control schemes for IPv6 over low power wireless personal area networks. The proposed schemes must be able to maximise the networks goodput, while minimising packet loss, energy consumption and packet delay. Two congestion control schemes, namely DCCC6 (Duty Cycle-Aware Congestion Control for 6LoWPAN Networks) and CADC (Congestion Aware Duty Cycle MAC) are proposed to realise this claim. DCCC6 performs congestion detection based on a dynamic buffer. When congestion occurs, parent nodes will inform the nodes contributing to congestion and rates will be readjusted based on a new rate adaptation scheme aiming for local fairness. The child notification procedure is decided by DCCC6 and will be different when the network is duty cycling. When the network is duty cycling the child notification will be made through unicast frames. On the contrary broadcast frames will be used for congestion notification when the network is not duty cycling. Simulation and test-bed experiments have shown that DCCC6 achieved higher goodput and lower packet loss than previous works. Moreover, simulations show that DCCC6 maintained low energy consumption, with average delay times while it achieved a high degree of fairness. CADC, uses a new mechanism for duty cycle adaptation that reacts quickly to changing traffic loads and patterns. CADC is the first dynamic duty cycle pro- tocol implemented in Contiki Operating system (OS) as well as one of the first schemes designed based on the arbitrary traffic characteristics of IPv6 wireless sensor networks. Furthermore, CADC is designed as a stand alone medium access control scheme and thus it can easily be transfered to any wireless sensor network architecture. Additionally, CADC does not require any time synchronisation algorithms to operate at the nodes and does not use any additional packets for the exchange of information between the nodes (For example no overhead). In this research, 10000 simulation experiments and 700 test-bed experiments have been conducted for the evaluation of CADC. These experiments demonstrate that CADC can successfully adapt its cycle based on traffic patterns in every traffic scenario. Moreover, CADC consistently achieved the lowest energy consumption, very low packet delay times and packet loss, while its goodput performance was better than other dynamic duty cycle protocols and similar to the highest goodput observed among static duty cycle configurations.

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