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Impacts of Changing the Transit Signal Priority Requesting Threshold on Bus Performance and General Traffic: A Sensitivity AnalysisSheffield, Michael Harmon 17 June 2020 (has links)
A sensitivity analysis was performed on the transit signal priority (TSP) requesting threshold to evaluate its impact on bus performance and general traffic. Two distinct bus routes were evaluated to determine the optimal requesting threshold that would balance the positive impacts on bus performance with the negative impacts on general traffic. Route 217, a conventional bus route, and the Utah Valley Express (UVX), a bus rapid transit line, utilize a dedicated short-range communication (DSRC)-based TSP system as part of their normal, day-to-day operations. Using field-generated data exclusively, bus performance and general traffic were evaluated over a 7-month period from February through August 2019. Bus performance was evaluated through on-time performance (OTP), schedule deviation, travel time, and dwell time, while the traffic analysis was performed by evaluating split failure, change in green time, and the frequency at which TSP was served. The requesting thresholds evaluated for Route 217 were 5-, 3-, 2-, and 0-minutes, which stipulate how far behind schedule the bus must be in order to request TSP. For UVX, 5-minutes and 2-minutes, as well as ON and OFF scenarios were evaluated; ON meant the buses were always requesting regardless of how late they were, while OFF meant that no requests were made and operations would be as if there were no TSP at all. A combination of observational and statistical analyses concluded with convincing evidence that OTP, schedule deviation, and travel time improve as the requesting threshold approaches zero with negligible impacts to general traffic. For Route 217, as the requesting threshold changed from 3, to 2, to 0 minutes, OTP increased 2.0 and 2.5 percent, respectively, mean schedule deviation improved 15.9 and 20.9 seconds, respectively, and travel time decreased at 72 percent of timepoints. Meanwhile, negative impacts to traffic occurred if an increase in split failure was measured after TSP was served, a phenomenon observed a maximum of once every 43 minutes. For UVX, as the requesting threshold changed from 5, to 2 minutes, to ON, OTP increased 7.6 and 4.7 percent, respectively, mean schedule deviation improved 24.3 and 15.0 seconds, respectively, and travel time decreased between 72 percent of timepoints. Thus, it is concluded that under the TSP system as implemented, bus performance improves as the requesting threshold approaches zero with inconsequential impacts to general traffic.
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Klinkertillverkning inom cementindustrin : Bränsleaskans inverkan på klinkerns kvalitet / Clinker manufacturing in the cement industry : The impact of the fuel ash on the clinker qualityThulin, Luna January 2021 (has links)
Under detta arbete har klinkertillverkningen hos en cementfabrik studerats. Arbetet behandlar möjligheter till förbättring, duglighet och måluppfyllelse för medelvärde och variation. En minskad variation bidrar till en jämnare kvalitet vilket i sin tur har en positiv påverkar på cementmalning, energi och kvalitet. De främsta orsakerna till variationen i klinkerns kvalitet är kvaliteten på råmjöl och aska från bränslen. Arbetet stöds av teorier som handlar om offensiv kvalitetsutveckling, förändring, ledarskap och kommunikation. Vid datainsamling och dataanalys har både kvalitativa och kvantitativa metoder tillämpats. Den insamlade materialet har hämtats från cementfabrikens egna databaser. Det slutsatser som kan dras utifrån denna studie är att klinkertillverkningsprocessen inte är statistisk jämvikt och innefattar stora mängder data som avviker från fabrikens målvärden. Askans effekt på klinkerns kalkmättnad beräknades till ca 17% av den totala variationen. Olika syn på kvalitetsbegreppet kan anses bidra till oönskad variation. / During this work, the clinker production at a cement factory has been studied. The work deals with opportunities for improvement, ability, and goal fulfillment for mean value and variation for the lime saturation factor in the clinker. A reduced variation offers a more even quality, which can have a positive impact on cement grinding, energy consumption, and quality. The main reasons for variations in the quality of the clinker are the quality of raw meal and ash from fuels. The work is supported by theories that deal with quality management, change, leadership, and communication. In data collection and data analysis, both qualitative and quantitative methods have been used. The collected material has been retrieved from the cement factory's own databases. The conclusions that can be drawn from this study are that the clinker manufacturing process is not stable and low process capability. The effect of the ash on the lime saturation of the clinker was calculated to be about 17% of the total variance. Different views on the concept of quality can also contribute to unwanted variation.
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Porovnání měření rychlosti vodoměrnou vrtulí a laserovým anemometrem / Comparison of speed measurement by hydrometric propeller and laser anemometerKosík, Ondřej January 2022 (has links)
This final thesis deals primarily with the comparison of two calibration approaches. It determines the degree of mutual agreement and tries to answer the reasons of their deviations. This agreement was measured by the LDA method. It was found that the calibration approach based on the reference framework of values of the previous bachelor thesis differs systematically from the calibration using calibration equations obtained from certified laboratories by -2 %. The causes of this deviation were investigated using LDA and PIV. Although a significant number of measurements were performed, all tested hypotheses were refuted and therefore it was not possible to determine their cause.
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Det borde skrivas en avvikelse på avvikelsehanteringen under pandemin : En kvalitativ studie av avvikelsehanteringen under covid-19-pandemin inom särskilda boenden i kommunal regiBjerneby, Sanna, Davidsson, Anna January 2021 (has links)
Coronakommissionen drog 2020 slutsatsen att strukturella samt organisatoriska brister förekommer inom särskilda boenden (Coronakommissionen, 2020). WHO:s (2017) studier inom hälso- och sjukvården visar att misstag ofta beror på bristfälliga system, processer och arbetsförfaranden. Systematiskt förbättringsarbete genomförs inom vård- och omsorg genom avvikelsehantering, egenkontroll och riskanalys med syftet att förbättra verksamhetens kvalitet (Socialstyrelsen, 2012). Studiens syfte var att belysa hur covid-19 påverkat avvikelsehanteringen inom kommunala särskilda boenden samt lyfta hur lärdomar dragits av framgångar och utmaningar kring avvikelsehanteringen och vidare systematiskt förbättringsarbete under pandemin. En kvalitativ studie med semistrukturerade intervjuer genomfördes med undersköterskor och enhetschefer för att fånga faktorer som bidragit till framgång samt utmaningar i pandemin, statistik- och dokumentgranskning utfördes. Empiriska data analyserades genom tematisk analys samt kopplades till teoretisk referensram. Slutsatsen synliggör hur systematiskt förbättringsarbete grundad på inrapporterade avvikelser möjliggörs genom kommunikation i team- att vara en lärande organisation, tydliga rutiner/arbetssätt, tillåtande klimat på arbetsplatsen och tydligt ledarskap. / The corona commission 2020 concluded a prevalence of structural and organisational flaws within nursing homes (Coronakommissionen, 2020). Studies from WHO (2017) within healthcare shows that mistakes often were caused by flawed systems, processes and working procedures. Systematic improvement within healthcare is accomplished by deviation reporting, independent control measures and risk analysis with the goal of quality improvement within the operation (Socialstyrelsen, 2012). The cause of the study was to illuminate the impact of covid-19 regarding the handlement of deviation reports within municipal nursing homes and to bring forth the lessons learnt through success and challenges regarding handlement of deviation reports and further systematic improvements during the pandemic. A qualitative study with semistructural interviews was conducted with assistant nurses and head of departments to gather factors contributing to success and challenges. Empiric data was analysed through thematic analysis and then attached to a theoretical framework. The conclusion illuminates how systemic improvement based on reported deviations are made possible through communication in a team- to be a learning organisation, explicit routines, accepting environment at the workplace and a thorough leadership. / <p>2021-06-06</p>
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Virtual Sensing of Hauler Engine SensorsHassan Mobshar, Muhammad Fahad, Hagblom, Sebastian January 2022 (has links)
The automotive industry is becoming more dependent on sustainable and efficient systems within vehicles. With the diverse combination of conditions affecting vehicle performance, such as environmental conditions and drivers' behaviour, the interest in monitoring machine health increases. This master thesis examines the machine learning approach to sensor reconstruction of hauler engine sensors for deviation detection applications across multiple domains. A novel proposal for sequence learning and modelling was by introducing a weighted difference of sequence derivatives. Impacts of including differences of derivatives assisted the learning capabilities of sequential data for the majority of the target sensors across multiple operating domains. Robust sensor reconstruction was also examined by using inductive transfer learning with a Long Short-Term Memory-Domain Adversarial Neural Network. Obtained results implied an improvement in using the Long Short-Term Memory-Domain Adversarial Neural Network, then using a regular Long Short-Term Memory network trained on both source and target domains. Suggested methods were evaluated towards model-based performance and computational limitations. The combined aspects of model performance and system performance are used to discuss the trade-offs using each proposed method.
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Managing Production deviations : A case study at Scania AB / Hantering av produktionsavvikelser : en fallstudie på Scania ABLiljedahl, Anders, Muftic, Armin January 2012 (has links)
The use of continuous improvement programs is a widespread practice present in many organizations throughout the world. CI-programs are mostly associated with Lean production and substantial focus in literature and research are on the applicable tools and methods. This focus has led to the lack of attention to the softer areas of CI such as implementation. The reason explaining this might be due to the difficulties of measuring success in these areas. In order to investigate production deviations within a company that uses CI a study was performed at the bus chassis assembly at Scania. The deviation handling process and all activities related to it is highly influenced by Scania’s Production System. The studies were conducted at an assembly area with observations and interviews taking place as well as an internal benchmarking performed at the engine assembly. The conclusion is that the area studied at Scania has the tools and methods needed (although with the need of adjustments) but the implementation part is lacking. This area will come to play a big part in taking SPS one step further. As a recommendation to the area studied in Scania a group of suggestions has been presented in this paper in order to improve the implementation of SPS. The managerial contribution of this paper is a group of important suggestions. The theoretical contribution of this paper can be seen as a case study that could create an increase insight in the complexity of this topic but also to increase the attention to the importance of it. / Ständiga förbättringar är ett världsomfattande fenomen som används inom flera organisationer. Oftast associerar man ständiga förbättringar med Lean och litteraturen kring ämnet beskriver för det mesta bara verktygen och metoderna som tillämpas. Detta focus har lett till att väldigt lite uppmärksamhet har riktats mot de mjukare delarna så som implementering. En orsak till detta kan vara svårigheten att mäta framgång inom området. För att undersöka avvikelser inom ett företag som arbetar med ständiga förbättringar så gjordes en studie på Scanias buss chassi montering. Avvikelsehanteringsprocessen påverkas väldigt mycket utav Scanias produktions system. Studier utfördes på ett monteringområde där man bland annat observerade, intervjuade samt utförde en benchmark på motormonteringen. Slutsatsen är att monteringsområdet där studien ägde rum på Scania har verktygen och metoderna som behövs (med behovet av mindre justeringar) men implementeringen har brister. Just implementeringen kommer spela en stor roll i att ta SPS ett steg längre. Som en rekommendation till monteringsområdet som undersöktes så har ett flertal förslag som kan förbättra SPS presenterats i denna rapport. Bidraget till lokala ledningen är ett antal viktiga förslag. Det teoretiska bidraget i denna rapport kan ses som en case studie som kan förbättra förståelsen för det komplexa ämnet samt att belysa det ytterligare och konstatera dess betydelse.
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Utvärdering av IMU-sensorers precision vid mätning av handledens vinkelhastigheter : Jämförande studie med ett optiskt spårningssystem / Evaluation of the Precision of IMU-sensors Measuring Wrist Angular Velocity : Comparative study with Optical Motion TrackingWingqvist, Jenny, Lantz, Josephine January 2019 (has links)
Belastningsskador hos arbetare är ett ökande problem hos olika företag och det har visat sig finnas en tydlig koppling mellan dessa skador och handledens vinkelhastigheten. Det är därför av stort intresse att kunna mäta dessa vinkelhastigheter på ett noggrant och smidigt sätt. Syftet med denna rapport är att utvärdera precisionen av IMU-sensorers förmåga att beräkna vinkelhastigheten av handleden. Detta görs genom att jämföra data från IMU-sensorer med data från ett optiskt spårningssystem (OTS), vilket klassas som en gold standard inom detta område. Ett experiment bestående av åtta övningar utfördes: tre standard rörelser (flexion och rotation i takterna 40, 90 och 140 slag per minut) och fyra simulerade arbeten (målning, pappersvikning, datorarbete och hårföning). Grad av överensstämmelse ges av 1,96 standardavvikelser (SD) för standardrörelserna (10 deltagare) vilka var -31,8 grader/s och 34,2 grader/s, medan för de simulerade arbetena var det -35,1 grader/s och 34,2 grader/s. Det lägsta medelvärdet av medelkvadratavvikelse (RMSD) var 15,7 grader/s och erhölls vid 40 BPM medan den högsta medelvärdet var 93,9 grader/s och erhölls vid målningsövningen. Medelvärdet av korrelationskoefficienten mellan IMU-sensorer och OTS varierade mellan 0,97 och 0,42 och korrelationskoefficienterna av deltagarnas 50:e percentiler av vinkelhastigheten var 0,95 för standardrörelserna och 0,96 för de simulerade arbetena. Medelvärdet av absoluta differensen mellan sensorer och OTS var givet i percentiler (10:e, 50:e och 90:e). Det största spannet för 50:e percentilen gavs vid 140 BPM (18,3 ± 24,6) och det minsta spannet vid 40 BPM (3,5 ± 4,7). Trots att det fanns mindre differenser mellan metodernas mätningar av vinkelhastighet, anser vi att IMU-sensorer har potential att användas för att mäta vinkelhastigheter hos handledens och med vidare utveckling kan den nuvarande differensen minimeras. / Musculoskeletal disorders (MSDs) are increasingly frequent amongst workers and there is a clear connection between work injuries and wrist angular velocities. One of the biggest issues therefore is the currently limited availability of means to measure these angular velocities. The aim of this study is to validate the usability of the IMU sensors to measure angular velocities. This is done by comparing the data from the IMU:s with the data obtained with the optical motion tracking system (OTS), which is considered gold standard within this field of studies. An experiment consisting of eight exercises was conducted: three standard movements (flexion and rotation in the pace 40, 90 and 140 repetitions per minute) and four simulated practical work tasks (painting, folding paper, computer exercise and using a hairdryer). The limits of agreement for the standard movements (10 subjects) were -31,8 degrees/s and 34,2 degrees/s, whereas for the simulated practical work tasks they were -35,1 degrees/s and 28,2 degrees/s. The lowest mean value of the root mean square deviation (RMSD) value was 15,7 degrees/s which represents the 40 BPM task whilst the highest mean value was 93,9 degrees/s which correspond to the painting task. The mean value of the correlation coefficients between the IMU:s and the OTS ranged between 0,97 and 0,42 and the correlation coefficient between the subjects 50:th percentiles of the angular velocity, was 0,95 for the standard movements whilst for the practical work tasks it was 0,96. The mean value of the absolute difference between the sensors and the OTS was given in percentiles (10th, 50th and 90th). The largest range within the 50th percentile occurred during the 140 BPM task (18,3 ± 24,6) and the smallest range during the 40 BPM task (3,5 ± 4,7). Although the measured angular velocities vary to a certain extent between the two methods, we conclude that the IMU sensors present the potential to work as measuring units for wrist angular velocities and with further development the current differences can be minimized. / Forte dnr: 2017-01209 "Enkel och tideffektiv metod att mät, analysera och presentera biomekaniskbelastning för hand-handled"
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Modelling management fees of mutual funds using multiple linearregression / Modellering av fonders förvaltningsavgift genom multilinjär regressionHallberg, David, Renström, Erik January 2017 (has links)
This paper seeks to investigate whether management fees, set by mutual funds, rely on a set of explanatory variables. The study includes equity, bond, and money market funds, all investing in securities registered in Sweden. Results obtained from the project show that changes in assets under management, standard deviation, and tracking error, for a course of 5 years, can provide some explanation to what management fees mutual funds set. In turn, this raises many interesting questions on how capital flows and fund differentiation affects the fees. Also, a market analysis of the Swedish fund market shows that elements of monopolistic competition are present. Finally, because of the scope of this study, several suggestions on further research have been made. / Denna artikel ämnar undersöka huruvida förvaltningsavgifter, satta av fonder, beror på ett antal förklarande variabler. Studien inkluderar aktie, obligations och korträntefonder, vilka investerar i värdepapper registrerade i Sverige. Resultat erhållna från projektet tyder på att förändringar i kapital under förvaltning, standardavvikelse och spårningsfel (tracking error), alla uppmätta över 5 år, delvis kan förklara vilka avgifter fonder sätter. I sin tur väcker detta flera intressanta frågor över hur kapitalflöden och fonddifferentiering påverkar avgifter. Dessutom visar en genomförd marknadsanalys över den svenska fondmarknaden att karaktäristiska drag av monopolistisk konkurrens är närvarande. Slutligen, i samband med studiens omfattning, så har flertalet förslag på vidare studier gjorts.
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Deviation occurrence analysis in a human intensive production environment by using MES dataPaz Alvarez, Alfonso January 2018 (has links)
Despite decades of automation initiatives, manual assembly still represents one of the most cost-effective approaches in scenarios with high product variety and complex geometry. It represents 50% of total production time and 20% of total production cost. Understanding human performance and its impact in the assembly line is key in order to improve the overall performance of an assembly line. Along this thesis work, by studying the deviations occurring in the line, it is aimed to understand how human workers are affected by certain functioning aspects of the assembly line. To do so, three different influence factors have been chosen, and then observed its impact in human performance: i. How past events occurring in the line affect the current action of the worker. ii. How do scheduled stops affect the current action of the worker. iii. How does theoretical cycle time affect the performance of the worker. In order to observe these influence relationships, it has been used data gathered in the shop floor from SCANIA's Manufacturing Execution System (MES). By applying methods of Knowledge Discovery in Database (KDD) data has been indexed and the analyzed providing the necessary results for the study. Finally, from the results shown, it can be inferred that variability on the functioning of the line does have an impact on human performance overall. However, due the complexity of the manufacturing system, impact in human performance might not be as regular as initially thought. / Trots decennier av automatiseringsinitiativ utgör manuell montering fortfarande en av de mest kostnadseffektiva metoderna i scenarier med hög produktsortiment och komplex geometri. Den representerar 50% av den totala produktionstiden och 20% av den totala produktionskostnaden. Att förstå mänsklig prestanda och dess inverkan i monteringsledningen är nyckeln för att förbättra den totala prestandan hos en monteringslinje. Utöver detta avhandlingsarbete, genom att studera avvikelserna som uppstår i linjen, syftar det till att förstå hur mänskliga arbetstagare påverkas av vissa fungerande aspekter av monteringslinjen. För att göra det har tre olika inflytningsfaktorer valts och sedan observerat dess inverkan i mänsklig prestation: i. Hur tidigare händelser som uppstår i linjen påverkar arbetarens nuvarande åtgärder. ii. Hur påverkar planerade stopp arbetstagarens nuvarande åtgärder. iii. Hur påverkar teoretisk cykeltid arbetarens prestation. För att observera dessa inflytningsrelationer har det använts data som samlats in i butiksgolvetfrån SCANIAs Manufacturing Execution System (MES). Genom att tillämpa metoder för Knowledge Discovery i Database (KDD) har data indexerats och analyseras vilket ger de nödvändiga resultaten för studien. Slutligen kan det framgå av de visade resultaten att variationen i linjens funktion har en inverkan på den mänskliga prestationen övergripande. På grund av tillverkningssystemets komplexitet kan emellertid effekten i mänsklig prestanda inte vara så regelbunden som ursprungligen tänkt.
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The Influence of Roughness on Electrical Properties of Single Rock Fractures / Inverkan av ojämnhet på elektriska egenskaper hos enskilda bergsprickorHou, Yu January 2023 (has links)
To investigate the relationship between the structural characteristics of rough single fracturesand the electrical properties of the rock. In this study, a series of physical models of roughand smooth single fractures were established using the finite element method and Ohm's lawto test the electrical conductivity. By varying the distance between the fracture surfaces, arange of individual fractures with different surface roughness characterized by the relativestandard deviation (RSD) was generated using COMSOL Multiphysics software.Subsequently, the intensity of current passing through the fractures and the influence of roughsurfaces on rock electrical properties were monitored. Numerical simulations demonstrated anon-linear relationship between the current intensity through the models and the RSDroughness, with the equivalent resistivity of the fractured rock increasing with higher RSDvalues. As the RSD roughness increased, the difference in equivalent resistivity betweenrough and smooth fractures also increased, indicating a greater impact of rough surfaces onelectrical properties. The equivalent resistivity of the rock model was 1.05-1.45 times that ofthe parallel plate model with same average aperture. The novelty of this study lies in directlyinvestigating the relationship between roughness of single fractures and rock electricalproperties in three-dimensional, providing insights for understanding the electrical behaviorof rock fractures. / För att undersöka sambandet mellan strukturella egenskaper hos ojämna enkelstrålar och deelektriska egenskaperna hos bergarten. I denna studie etablerades en serie fysiska modeller avojämna och jämna enkelstrålar genom att använda finita elementmetoden och Ohms lag föratt testa elektrisk ledningsförmåga. Genom att variera avståndet mellan strålytornagenererades en rad individuella strålar med olika ytjämnhet som karakteriseras av relativstandardavvikelse (RSD) med hjälp av COMSOL Multiphysics-programvara. Därefterövervakades intensiteten av ström som passerade genom strålarna och inflytandet av ojämnaytor på bergens elektriska egenskaper. Numeriska simuleringar visade på ett icke-linjärtsamband mellan strömintensiteten genom modellerna och RSD-ytjämnheten, där denekvivalenta resistiviteten hos den spruckna bergarten ökade med högre RSD-värden. NärRSD-ytjämnheten ökade, ökade även skillnaden i ekvivalent resistivitet mellan ojämna ochjämna strålar, vilket indikerar en större påverkan av ojämna ytor på de elektriskaegenskaperna. Den ekvivalenta resistiviteten hos bergmodellen var 1,05–1,45 gånger högreän den hos parallellplattanmodellen med samma genomsnittliga apertur. Nyheten i dennastudie ligger i att direkt undersöka sambandet mellan ytjämnheten hos enkelstrålar ochbergens elektriska egenskaper på en tredimensionell skala, vilket ger värdefulla insikter föratt förstå det elektriska beteendet hos bergstrålar och ytterligare förbättra modeller.
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