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Frivillig miljökompensation : Klädkonsumentens vilja att täcka plaggets fulla kostnad / Voluntary Environmental Offset for ClothingJohansson Tapper, Erik, Svensson, Sofia January 2017 (has links)
Det är känt att modeindustrin har ett stort anspråk på miljön, men trots det finns det inga fungerande lösningar på problemet i dagsläget. Ett sätt att komma till bukt med problemet äratt låta konsumenten miljökompensera vid köptillfället. Den här studien undersöker konsumenters inställning till en frivillig miljökompensation vid klädköp. Liknande studier har gjorts tidigare, då på flygresenärers vilja att frivilligt klimatkompensera för koldioxidutsläpp. Det har därför varit av intresse att testa liknande undersökningsmetod på konsumenter imodeindustrin. Tidigare forskning har konstaterat att ett flertal variabler är betydande för konsumentens vilja göra grönare konsumtionsval. Detta har mynnat ut i fyra hypoteser som testar hur konsumenters attityd till miljökompensation, upplevda konsumenteffektivitet, upplevda miljökunskap samt kön korrelerar med viljan att miljökompensera. Studien har även undersökt hur konsumenternas vilja att kompensera påverkar det ekonomiska värdet som konsumenten sätter på miljöproblemen kopplade till klädproduktion. Undersökningen bygger på 225 enkätsvar från studenter vid en medelstor svensk högskola. Resultaten från studien visar på signifikanta samband mellan flera av de förklarande variablerna och viljan att delta i frivillig miljökompensation. Den genomsnittliga kompensationsnivån uppgår till halva plaggets försäljningspris, vilket är en uppseendeväckande siffra. Respondenternas preferenser visar även att miljökompensationen bör fördelas lika över olika projekt för bättre miljö. / Although it’s known what footprint the global fashion industry has, few solutions have effectively managed to tackle the problem. One solution is to let the consumer participate in avoluntary environmental offset. This study investigates what variables affecting the consumer’s willingness to participate in such offset. Similar studies on air travelers’ voluntarycarbon offset have been done before. It’s therefore of interest to use the same preference method on consumers of the fashion industry. Previous research present a number of independent variables affecting the willingness to participate in voluntary offset. This study uses four hypotheses to explain consumers’ stated preferences. These include attitudes, perceived consumer effectiveness, perceived ecoliteracy and gender. The study uses a contingent valuation method to explain how the willingness to participate correlates with the hypothetical value of the voluntary environmental offset. An online survey was conducted and included data of 225 respondents. The results show significant correlations among several of the independent variables and the willingness to participate in voluntary environmental offset. The average value of offset reached about half the selling price of a simulated garment, which is staggering. The respondents’ preferences on how the money from the offset should be allocated tell of an equal share among projects for a better environment. The study is a bachelor thesis written in Swedish.
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Business as usual? : instituting markets for carbon creditsBroderick, John Foreman January 2011 (has links)
Climate change mitigation necessitates substantial alterations to patterns of worldwide economic activity, be that reduction in demand, switches to new technology or 'end-of-pipe' abatement of greenhouse gases. There are profound political, economic and ethical questions surrounding the governance of the means, rate and location of change. Within advanced capitalist economies and internationally through the auspices of the United Nations Framework Convention on Climate Change emissions trading systems have been introduced as part of the broader neoliberal attempts to 'correct market failure' through the definition of new property rights.This thesis investigates the development, constitution and consequences of institutions for the production, exchange and consumption of credits for emissions reductions. Such credits are financial instruments awarded to organisations for putative reductions in emissions from 'business as usual'. In consumption, credits are equated with a quantity of emissions released elsewhere. The 'Instituted Economic Process' framework (Randles and Harvey, 2002) is used to distinguish the various classes of agent involved in these exchanges and identify the economic and non-economic relationships that constitute these institutions. Inspired by the economic anthropology of Karl Polanyi, this approach asks how economic activity is organised and stabilised within society without presuming that there are universal economic laws of 'the market', that there are essential properties of commodities and agents, or that all economic transfers are conducted within markets.I argue that crediting is a socially contingent process of commodification of atmospheric pollution which is both ontologically and normatively problematic. Extant institutions are shown to be precarious by appealing to neutral techno-scientific justifications but remaining reliant on subjective judgement. However, they are sufficiently consistent and credible that they persist and expand. These findings are of interest to the academic communities of political economy and environmental and economic geography, climate change policy makers and the environmental movement more broadly.
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Experimental and Numerical Investigation of Positively and Negatively-buoyant Round Jets in a Stagnant Water AmbientAlfaifi, Hassan 20 November 2019 (has links)
Discharge of brine wastewater produced from industrial plants into adjacent coastal water bodies is considered as a preferable and common method currently used in many offshore industrial plants. Therefore, it is important to carefully study the behavior of jets and their environmental impacts on water bodies close to the discharge points, especially when the density is different between the jets and the receiving water. The main goal of this study is to improve the understanding of the mixing behaviour of jet trajectories for positively (offset) and negatively (inclined) buoyant jets when density is considered a significant factor, and also to examine the accuracy of some RANS turbulence models and one type of artificial neural network in predicting jet trajectory behaviours.
In the first part of this study, experiments using a PIV system for offset buoyant jets were conducted in order to study the effect of the density differences (due to salinity [nonthermal] or temperature [thermal]) between the discharge and the receiving water body on the jet behavior, and the results showed that the nonthermal jets behaved differently as compared to the thermal jets, even though the densimetric Froude numbers (Frd) and density differences (∆ρ) were similar. In addition, a Reynolds-averaged Navier-Stokes (RANS) numerical model was performed using open-source CFD code (OpenFOAM) with a developed solver (modified form of the pisoFoam solver). The realizable k-ε model showed the best prediction among the models.
Secondly, an extensive experimental study of an inclined dense jet for two angles (15°and 52°) was conducted to study the effect of these angles on the jets’ geometrical characteristics in the presence of a wide range of densimetric Froude numbers as well as with different discharge densities. More experimental data were obtained for these angles to be added to the previous data for the purpose of calibrating, validating, and comparing the various numerical models for future studies. The results of these experiments are used to evaluate the performance of a type of artificial neural network method called the group method of data handling (GMDH), and the GMDH results are then compared with existing analytical solutions in order to prove the accuracy of the GMDH method in simulating mixing behaviors in water bodies.
Thirdly, a comprehensive study on predicting the geometrical characteristics of inclined negatively-buoyant jests using GMDH approach was conducted. The superiority of this model was demonstrated statistically by comparing to several previous analytical models. The results obtained from this study confirm that the GMDH model was highly accurate and was the best among others for predicting the geometrical characteristics of inclined negatively-buoyant jests.
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Development of Zn-IV-N2 and III-N/Zn-IV-N2 Heterostructures for High Efficiency Light Emitting Diodes Emitting Beyond Blue and GreenKarim, Md Rezaul 13 October 2021 (has links)
No description available.
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Návrh operačního zesilovače CMOS / Design of operational amplifier CMOSNavrátil, Jakub January 2009 (has links)
The present work deals with issues of a design of operational transconductance amplifier in technology CMOS AMIS 0,7 um. The aim of the work is to design a accurate operational amplifier with a low input differential voltage.
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Autokompenzace ofsetu operačního zesilovače pro přesná měření / Autocompensation of operational amplifier offset for precise measurementPrášek, David January 2009 (has links)
This work deals with the problems of the design of two stage operational amplifier with automatic offset compensation for precise measurement. Full design operational amplifier is aimed at appropriate realization in technology CMOS07 with usage Cadence design environment. The goal of the design is minimum offset value as well as the adherence to the parameters of the operational amplifier which are introduced in submission of the thesis.
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Readout Circuits for a Z-axis Hall Sensor with Sensitivity Drift CalibrationZhang, Jianbo January 2014 (has links)
Hall effect magnetic sensors have gradually gained dominance in the market of magnetic sensors during the past decades. The compatibility of Hall sensors with conventional CMOS technologies makes monolithic Hall sensor microsystem possible and economic. An attractive application is the contactless current sensor by using Hall sensors to measure the magnetic field generated by the electrical current. However, Hall sensors exhibit several non-idealities, i.e., offset, noise and sensitivity drift, which limit their precision. Therefore, effective techniques to reduce these imperfections are desired. This thesis presents the design of a new readout scheme for Hall magnetic sensor with low offset, low noise and low sensitivity drift. The Hall sensor is realized in N-well as Hall plate and modeled in Verilog-A for the purpose of co-simulation with interface circuits. The self-calibrated system is composed of two identical Hall plates, preamplifiers and a first-order ΣΔ modulator, which can be fully integrated monolithically. Four-phase spinning current technique and chopper stabilization technique have been employed to reduce the offset and 1/fnoise of Hall platesand OTA, respectively. Integrated coils are used to generate the reference magnetic field for calibration. The preamplifiers amplify the signal and separate the Hall voltage and reference voltage. The ΣΔ modulator reduces the thermal drift by using Hall voltage as the modulator input and reference voltage as the DAC output. This new calibration technique also compensates the thermal drifts of the biasing current and readout circuits. The overall system is implemented in NXP140nm CMOS process with 1.8V supply. The Virtuoso/Spectre simulation results show residual drifts lower than 10ppm/ ̊C, which are 3-5 times lower than the state of the art. The input magnetic field and temperature range are ±100mT and -40 ̊C to 120 ̊C, respectively.
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An evaluation of solar powered irrigation as carbon offset projectsOlsson, Alexander January 2016 (has links)
Carbon offsets have been developed as one tool to incentivise investments by developed nations in climate change mitigation activities in developing countries. The carbon offsets can be used towards the countries’ own mitigation targets but are also meant to benefit developing countries by providing a pathway to clean development. Photovoltaic water pumping (PVWP) technology is a solution to use PV for irrigation, which can be used to restore degraded grasslands and help farmers adapt to climate change. Restoration of degraded grasslands increases the production of grass and will therefore increase the amount of carbon in the soil, a process that may mitigate climate change. However, poor farmers often have limited access to irrigation technology and this thesis assesses how carbon offsets may bring revenues to increase adaption of PVWP technology in remote areas of the Chinese grasslands. PV modules can be used to mitigate climate change in different ways; the most common is to produce electricity to replace fossil fuel power capacity. The novelty of this thesis is that it assesses the alternative mitigation possibilities for the PVWP project proposed here. Further, consideration of water constraints that limit the applicability of the technology and a framework to assess the trade-offs between potential downstream water impacts and environmental co-benefits of the project add to the novelty of this thesis. Policy barriers for the project will also be considered. Used to restore severely degraded grasslands, PVWP projects show high carbon sequestration potential and successfully compete with grid electricity as carbon offset projects. A case is analysed and it shows that the carbon market could play a role in increasing the feasibility of PVWP projects. However, water issues make project implementation very site-specific and some indicators to determine feasibility is proposed to be blue water availability, evaporation recycling ratio and water productivity. Water use must also be looked at with respect to climate, food and energy security, calling for a nexus approach to evaluate the project suitability. In May 2016, grassland management projects are excluded from the Clean Development Mechanism to the Kyoto Protocol, and this limits project implementation to the voluntary markets. / Avhandlingen är ämnad att läsas av beslutsfattare inom klimatområdet samt aktörer på de olika klimatkompensationsmarknaderna. Klimatkompensation har utvecklats som ett verktyg för att stimulera industriländers investeringar i klimatprojekt i utvecklingsländer. Klimatkompensation kan användas för att nå industriländernas egna klimatmål men är också tänkta att gynna utvecklingsländer genom att tillhandahålla en ”ren” utvecklingsmöjlighet. Solcellsdrivna vattenpumpar (eng. photovoltaic water pumping: PVWP) är en teknik för att använda solceller för bevattning. Tekniken kan användas för att restaurera degraderade gräsmarker och för att hjälpa jordbrukare anpassa sig till klimatförändringarna. Restaurering av gräsmarker ökar produktionen av gräs vilket medför ökad mängden kol i marken, en process som kan mildra klimatförändringarna. Men fattiga bönder har ofta begränsad tillgång till bevattningsteknik och denna avhandling utvärderar hur klimatkompensation kan ge intäkter för att öka användningen av PVWP i avlägsna delar på den kinesiska slätten. Solceller kan användas för att mildra klimatförändringarna på olika sätt och vanligast är att producera el för att ersätta fossila bränslen. Det är därför viktigt att titta på alternativkostnaden för PVWP-projekten som föreslås här. Vidare begränsar vattentillgången projekten och ett ramverk för att tydliggöra avvägningar mellan vattenrelaterade problem och miljömässiga fördelarna med ett projekt är nödvändigt. Klimatpolitiska styrmedel sätter också upp vissa begränsningar för projekten. Om PVWP används för att återställa mycket degraderade gräsmarker, visar projekten hög klimatnytta och de kan framgångsrikt konkurrera med solel till nätet som klimatkompensationsprojekt. En fallstudie visar att klimatkompensationsmarknaden skulle kunna spela en viss roll för att öka antalet PVWP-projekt. Däremot gör vattenfrågan projektens geografiska plats viktig och indikatorer för att avgöra genomförbarheten föreslås vara ”blåvattentillgång”, ”förångningsåtervinning” och ”vattenproduktivitet”. Vattenanvändningen måste också ses i förhållande till klimat, mat- och energisäkerhet, vilket kräver en nexusstrategi för att utvärdera projekten. I skrivande stund (maj 2016) är projekt rörande skötsel av gräsmarker exkluderade från mekanismen för ren utveckling (CDM) till Kyotoprotokollet och detta begränsar projekten till de frivilliga klimat-kompensationsmarknaderna. / <p>QC 20160711</p> / Demonstration and Scale-Up of Photovoltaic Solar Water Pumping for the Conservation of Grassland and Farmland in China
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Space-Time Coding with Offset ModulationsNelson, N. Thomas 26 November 2007 (has links) (PDF)
In this dissertation it is shown that the telemetry versions of Feher-patented QPSK (FQPSK-JR) and shaped offset QPSK (SOQPSK-TG) can be interpreted as both cross-correlated, trellis-coded quadrature modulation (XTCQM) and continuous phase modulation (CPM). Based on these representations, both modulations can be detected with near optimal bit error rate performance using a common detector that is formulated as either an XTCQM detector, a traditional CPM detector, or a pulse amplitude modulation (PAM) detector (due to the PAM decomposition of the CPM representations of these modulations). In addition it is shown that the complexity of the XTCQM detector for SOQPSK-TG can be reduced by a factor of 128 with only a 0.2 dB loss in detection efficiency relative to the optimum detector. Three decoders for STC encoded OQPSK are presented. One decoder has a bit error rate performance that matches the SISO case but with much higher complexity than that of the QPSK decoder. A second decoder matches the simplicity of the decoder for STC encoded non-offset QPSK but with a loss of 3 dB relative to the single-input, single-output (SISO) case. A third decoder matches SISO performance with lower complexity than the first one. These results for STC encoded OQPSK are extended to STC SOQPSK. It is shown that the maximum likelihood decoder is not computationally feasible. Two suboptimal decoders based on the STC OQPSK decoders are presented. These decoders have much higher complexity than their OQPSK counterparts, and they provide inferior bit error rate performance. In addition, a least squares decoder for STC encoded SOQPSK is presented which is less complex and has better performance (within 1 dB of the SISO bound) than the previous two decoders. This decoder also handles the differential delays that can occur on aeronautical telemetry channels.
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Frequency Domain Independent Component Analysis Applied To Wireless Communications Over Frequency-selective ChannelsLiu, Yuan 01 January 2005 (has links)
In wireless communications, frequency-selective fading is a major source of impairment for wireless communications. In this research, a novel Frequency-Domain Independent Component Analysis (ICA-F) approach is proposed to blindly separate and deconvolve signals traveling through frequency-selective, slow fading channels. Compared with existing time-domain approaches, the ICA-F is computationally efficient and possesses fast convergence properties. Simulation results confirm the effectiveness of the proposed ICA-F. Orthogonal Frequency Division Multiplexing (OFDM) systems are widely used in wireless communications nowadays. However, OFDM systems are very sensitive to Carrier Frequency Offset (CFO). Thus, an accurate CFO compensation technique is required in order to achieve acceptable performance. In this dissertation, two novel blind approaches are proposed to estimate and compensate for CFO within the range of half subcarrier spacing: a Maximum Likelihood CFO Correction approach (ML-CFOC), and a high-performance, low-computation Blind CFO Estimator (BCFOE). The Bit Error Rate (BER) improvement of the ML-CFOC is achieved at the expense of a modest increase in the computational requirements without sacrificing the system bandwidth or increasing the hardware complexity. The BCFOE outperforms the existing blind CFO estimator [25, 128], referred to as the YG-CFO estimator, in terms of BER and Mean Square Error (MSE), without increasing the computational complexity, sacrificing the system bandwidth, or increasing the hardware complexity. While both proposed techniques outperform the YG-CFO estimator, the BCFOE is better than the ML-CFOC technique. Extensive simulation results illustrate the performance of the ML-CFOC and BCFOE approaches.
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