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Short-term Underground Mine Scheduling : Constraint Programming in an Industrial ApplicationÅstrand, Max January 2018 (has links)
The operational performance of an underground mine depends critically on how the production is scheduled. Increasingly advanced methods are used to create optimized long-term plans, and simultaneously the actual excavation is getting more and more automated. Therefore, the mapping of long-term goals into tasks by manual short-term scheduling is becoming a limiting segment in the optimization chain. In this thesis we study automating the short-term mine scheduling process, and thus contribute to an important missing piece in the pursuit of autonomous mining. First, we clarify the fleet scheduling problem and the surrounding context. Based on this knowledge, we propose a flow shop that models the mine scheduling problem. A flow shop is a general abstract process formulation that captures the key properties of a scheduling problem without going into specific details. We argue that several popular mining methods can be modeled as a rich variant of a k-stage hybrid flow shop, where the flow shop includes a mix of interruptible and uninterruptible tasks, after-lags, machine unavailabilities, and sharing of machines between stages. Then, we propose a Constraint Programming approach to schedule the underground production fleet. We formalize the problem and present a model that can be used to solve it. The model is implemented and evaluated on instances representative of medium-sized underground mines. After that, we introduce travel times of the mobile machines to the scheduling problem. This acknowledges that underground road networks can span several hundreds of kilometers. With this addition, the initially proposed Constraint Programming model struggles with scaling to larger instances. Therefore, we introduce a second model. The second model does not solve the interruptible scheduling problem directly; instead, it solves a related uninterruptible problem and transforms the solution back to the original time domain. This model is significantly faster, and can solve instances representative of large-sized mines even when including travel times. Lastly, we focus on finding high-quality schedules by introducing Large Neighborhood Search. To do this, we present a domain-specific neighborhood definition based on relaxing variables corresponding to certain work areas. Variants of this neighborhood are evaluated in Large Neighborhood Search and compared to using only restarts. All methods and models in this thesis are evaluated on instances generated from an operational underground mine. / Underjordsgruvans operativa prestanda är till stor del beroende av schemaläggningen av de mobila maskinerna. Allt mer avancerade metoder används för att skapa optimerade långtidsplaner samtidigt som produktionsaktiviteterna blir allt mer automatiserade. Att överföra långtidsmål till aktiviteter genom manuell schemaläggning blir därför ett begränsande segment i optimeringskedjan. I denna avhandling studerar vi automatisering av schemaläggning för underjordsgruvor och bidrar således med en viktig komponent i utvecklandet av autonom gruvdrift. Vi börjar med att klargöra schemaläggningsproblemet och dess omgivande kontext. Baserat på detta klargörande föreslår vi en abstraktion där problemet kan ses som en flow shop. En flow shop är en processmodell som fångar de viktigaste delarna av ett schemaläggningsproblem utan att hänsyn tas till allt för många detaljer. Vi visar att flera populära gruvbrytningsmetoder kan modelleras som en utökad variant av en k-stage hybrid flow shop. Denna utökade flow shop innehåller en mix av avbrytbara och icke avbrytbara aktiviteter, eftergångstid, indisponibla maskiner samt gemensamma maskinpooler för vissa steg. Sedan föreslår vi ett koncept för att lösa schemaläggningsproblemet med hjälp av villkorsprogrammering. Vi formaliserar problemet och presenterar en modell som kan användas för att lösa det. Modellen implementeras och utvärderas på probleminstanser representativa för mellanstora underjordsgruvor. Efter det introducerar vi restider för de mobila maskinerna i schemaläggningsproblemet. Detta grundar sig i att vägnätet i underjordsgruvor kan sträcka sig upp till flera hundra kilometer. Med det tillägget får den initiala villkorsprogrammeringsmodellen svårt att lösa större instanser. För att möta det problemet så introducerar vi en ny modell. Den nya modellen löser inte det avbrytbara problemet direkt utan börjar med att lösa ett relaterat, icke avbrytbart, problem för att sedan transformera lösningen tillbaka till den ursprungliga tidsdomänen. Denna modell är betydligt snabbare och kan lösa probleminstanser representativa för stora underjordsgruvor även när restider inkluderas. Avslutningsvis fokuserar vi på att hitta scheman av hög kvalitet genom att optimera med Large Neighborhood Search. För att åstadkomma detta presenterar vi ett domänspecifikt grannskap baserat på att relaxera variabler som rör aktiviteter inom vissa produktionsområden. Flera varianter av detta grannskap utvärderas och jämförs med att enbart använda omstarter. Alla metoder och modeller i den här avhandlingen är utvärderade på genererade instanser från en operativ underjordsgruva. / <p>QC 20181026</p>
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Measurement of branching fraction and search for CP violation in D0 → Ks0 Ks0 π+ π- decays at Belle experimentSangal, Aman January 2022 (has links)
No description available.
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Study of continuous-phase four-state modulation for cordless telecommunications. Assessment by simulation of CP-QFSK as an alternative modulation scheme for TDMA digital cordless telecommunications systems operating in indoor applicationsBomhara, Mohamed A. January 2010 (has links)
One of the major driving elements behind the explosive boom in wireless revolution is the advances in the field of modulation which plays a fundamental role in any communication system, and especially in cellular radio systems. Hence, the elaborate choice of an efficient modulation scheme is of paramount importance in the design and employment of any communications system. Work presented in this thesis is an investigation (study) of the feasibility of whether multilevel FSK modulation scheme would provide a viable alternative modem that can be employed in TDMA cordless communications systems. In the thesis the design and performance analysis of a non-coherent multi-level modem that offers a great deal of bandwidth efficiency and hardware simplicity is studied in detail. Simulation results demonstrate that 2RC pre-modulation filter pulse shaping with a modulation index of 0.3, and pre-detection filter normalized equivalent noise bandwidth of 1.5 are optimum system parameter values. Results reported in chapter 5 signify that an adjacent channel rejection factor of around 40 dB has been achieved at channel spacing of 1.5 times the symbol rate while the DECT system standards stipulated a much lower rejection limit criterion (25-30dB), implying that CP-QFSK modulation out-performs the conventional GMSK as it causes significantly less ACI, thus it is more spectrally efficient in a multi-channel system. However, measured system performance in terms of BER indicates that this system does not coexist well with other interferers as at delay spreads between 100ns to 200ns, which are commonly encountered in such indoor environment, a severe degradation in system performance apparently caused by multi-path fading has been noticed, and there exists a noise floor of about 40 dB, i.e. high irreducible error rate of less than 5.10-3. Implementing MRC diversity combiner and BCH codec has brought in a good gain. / Higher Education Ministry
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Search for leptonic CP violation using measurements of neutrino oscillations and neutrino-nucleus interactions / ニュートリノ振動およびニュートリノ反応の測定を用いたレプトンにおけるCP対称性の破れの探索Yasutome, Kenji 24 November 2023 (has links)
京都大学 / 新制・課程博士 / 博士(理学) / 甲第24962号 / 理博第4987号 / 新制||理||1712(附属図書館) / 京都大学大学院理学研究科物理学・宇宙物理学専攻 / (主査)教授 中家 剛, 教授 永江 知文, 教授 田島 治 / 学位規則第4条第1項該当 / Doctor of Science / Kyoto University / DFAM
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Structure Property Relationships in Various Layered Polymeric SystemsRanade, Aditya Prakash January 2007 (has links)
No description available.
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Possible Interactions of Serotonin and Oxytocin in the Neural Regulation of Aggressive BehaviorHazlett, Emily G. 15 May 2012 (has links)
No description available.
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Tensors: An Adaptive Approximation Algorithm, Convergence in Direction, and Connectedness PropertiesMcClatchey, Nathaniel J. 03 July 2018 (has links)
No description available.
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The Effect of Hippotherapy on Seated Trunk StabilityWolff, Whitney L. 30 April 2018 (has links)
No description available.
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Characterization and Saccharification of Ionic Liquid Pretreated Lignocellulosic BiomassSamayam, Indira Priya January 2011 (has links)
No description available.
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Measurement of B_s to D_s^(*)+D_s^(*)- and Determination of the B_s-B_sbar Width Difference DeltaGamma_s Using e+e- collisionsEsen, Sevda 28 September 2012 (has links)
No description available.
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