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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.
1

Smarta parkeringsplatser : MultiTech mDot-baserade parkeringsplatser utan extern strömförsörjning

Svensson, Oskar January 2017 (has links)
Internet of Things är ett begrepp som innebär att alla tänkbara enheter kan kommunicera med varandra. Utvecklingen är snabb och antalet uppkopplade enheter ökar enormt. Detta medför bland annat att samhället blir effektivare vilket innebär både ekonomiska och miljömässiga fördelar. Genom att göra parkeringsplatser smarta kan de lediga platserna snabbare lokaliseras vilket minskar både miljöpåverkan och bränslekostnad. Eftersom strömförsörjning kan vara ett problem vid en del parkeringsplatser undersöks huruvida det är möjligt att åstadkomma smarta parkeringsplatser baserat på en enhet utan extern strömförsörjning. Undersökningen görs genom att konstruera en prototyp och på den utvärdera ström- och effektförbrukning samt batteritid. Dessutom analyseras om en annan design på prototypen skulle prestera bättre genom att uppskatta strömförbrukningen för en sådan design och därefter beräkna effektförbrukning och batteritid. Prototypens konstruktion bestod av en ultraljudsgivare inklusive styrenhet, en mikrokontroller kallad mDot, ett 9 V-batteri och en strömbrytare. Med mDot:en kunde data sändas till en server via LoRaWAN. De utförda mätningarna och beräkningarna visade att prototypen drar mycket ström. En enhet med tillräcklig prestanda är dock möjlig att konstruera genom att utföra beräkningar i mDot:en istället för i ultraljudsgivarens styrenhet. Detta skulle minska strömförbrukningen vilket förlänger batteritiden. Uppskattningar visade även att batteritiden för en sådan enhet ökar exponentiellt mot tiden i viloläge. Slutsatsen är att batteritiden varierar beroende på hur enheten är designad samt hur länge enheten är i viloläge. Det är dock möjligt att konstruera en enhet utan extern strömförsörjning som har tillräckligt bra prestanda för att åstadkomma smarta parkeringsplatser. / Internet of Things is a term for describing that every imaginable device can communicate with each other. The development in the field is fast and the amount of connected devices increases at an enormous rate. This means that the society becomes more efficient and some part of this is economic as well as environmental benefits. By making parking lots smart, the vacant lots can be located more quickly thus reducing environmental impact and fuel cost. At some parking lots there is no power supply. This report investigates whether or not it is possible to achieve smart parking lots based on a device without external power supply. The investigation is done by constructing a prototype and evaluate its current and power consumption as well as its battery life. Furthermore, an investigation is done to find out if another design can perform better than the prototype. This is done by making assumptions of how another design might look and from that estimate its current consumption and then calculating power consumption and battery life. The prototype constructed existed of an ultrasonic sensor including control unit, a microcontroller called mDot, a 9 V battery and a power switch. The mDot was able to send data to a server via LoRaWAN. The performed measurements and calculations showed that the prototype used to much current. However, a device with sufficient performance is possible to construct by doing the computation in the mDot instead of in the ultrasonic sensors control unit. This would increase the battery life of the device. Estimations showed that the battery life of such a device increases exponentially to the sleep time. The conclusion is that the battery life will vary depending on the design and the sleep time of the device. It is however possible to design a device without external power supply that has sufficiently good performance to enable smart parking lots.
2

Evaluation of Rapidly Growing Vegetation on Mississippi Roadsides

Bradford, Timothy, Jr. 17 August 2013 (has links)
Non-point source pollution caused by erosion from road construction poses hazardous environmental effects. Percolation and infiltration of nutrients into groundwater can also be detrimental to the surrounding environment. In addition, annual roadside maintenance budget exceeded $14 million in 2011 for Mississippi. Objectives of this research were to evaluate rapidly established short-statured species in an effort to prevent erosion, combat non-point source pollution, reduce mowing cost, and provide quick cover following propagation. Factors evaluated were rate of establishment, plant cover, and mowing requirement. MDOT’s standard seed mix was evaluated along with Pennington’s SlopeMaster product and different combinations of selected plant species. Visual and image analysis showed oilseed radish plants established the quickest and provided the most cover. All sod treatments provided instant cover while Pennington’s Slopemaster product, as well as mixes that contained bermudagrass or bahiagrass, provided sufficient cover, but not in a timely manner.

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