Dissertations / Theses on the topic 'Die pickup'
To see the other types of publications on this topic, follow the link: Die pickup.
Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles
Consult the top 50 dissertations / theses for your research on the topic 'Die pickup.'
Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.
You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.
Browse dissertations / theses on a wide variety of disciplines and organise your bibliography correctly.
1
Mourdjis, Philip James. "The pickup and multiple delivery problem." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/18582/.
Full textAbstract:
This thesis presents my work on the pickup and multiple delivery problem, a real-world vehicle routing and scheduling problem with soft time windows, working time and last-in-first-out constraints, developed in collaboration with Transfaction Ltd., who conduct logistics analysis for several large retailers in the UK. A summary of relevant background literature is presented highlighting where my research fits into and contributes to the broader academic landscape. I present a detailed model of the problem and thoroughly analyse a case-study data set, obtaining distributions used for further research. A new variable neighbourhood descent with memory hyper-heuristic is presented and shown to be an effective technique for solving instances of the real-world problem. I analyse strategies for cooperation and competition amongst haulage companies and quantify their effectiveness. The value of time and timely information for planning pickup and delivery requests is investigated. The insights gained are of real industrial relevance, highlighting how a variety of business decisions can produce significant cost savings.
2
Eriksson, Peter. "Utveckling av påbyggnadsskåp till pickup-bil." Thesis, Luleå tekniska universitet, Institutionen för teknikvetenskap och matematik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-73521.
Full text
3
Krypczyk, Veikko. "Nachbarschaftssucheverfahren für dynamische Pickup- und Delivery-Probleme." Hagen Fernuniversität Hagen, 2010. http://d-nb.info/1001671643/34.
Full text
4
Taut, Andreas [Verfasser]. "Pickup Ions in the Heliosphere / Andreas Taut." Kiel : Universitätsbibliothek Kiel, 2018. http://d-nb.info/1155760824/34.
Full text
5
Nowak, Maciek A. "The Pickup and Delivery Problem with Split Loads." Diss., Georgia Institute of Technology, 2005. http://hdl.handle.net/1853/7223.
Full textAbstract:
This dissertation focuses on improvements in vehicle routing that can be gained by allowing multiple vehicles to service a common load. We explore how costs can be reduced through the elimination of the constraint that a load must be serviced by only one vehicle. Specifically, we look at the problem of routing vehicles to service loads that have distinct origins and destinations, with no constraint on the amount of a load that a vehicle may service. We call this the Pickup and Delivery Problem with Split Loads (PDPSL). We model this problem as a dynamic program and introduce structural results that can help practitioners implement the use of split loads, including the definition of an upper bound on the benefit of split loads. This bound indicates that the routing cost can be reduced by at most one half when split loads are allowed. Furthermore, the most benefit occurs when load sizes are just above one half of vehicle capacity.
We develop a heuristic for the solution of large scale problems, and apply this heuristic to randomly generated data sets. Various load sizes are tested, with the experimental results supporting the finding that most benefit with split loads occurs for load sizes just above one half vehicle capacity. Also, the average benefit of split loads is found to range from 6 to 7% for most data sets. The heuristic was also tested on a real world example from the trucking industry. These tests reveal the benefit of both using split loads and allowing fleet sharing. The benefit for split loads is not as significant as with the random data, and the various business rules added for this case are tested to find those that have the most impact. It is found that an additional cost for every stop the vehicle makes strictly limits the potential for benefit from split loads. Finally, we present a simplified version of the PDPSL in which all origins are visited prior to any destination on a route, generalizing structural results from the Split Delivery Vehicle Routing Problem for this problem.
6
Narkhede, Sachin Narayan Lankarani Hamid M. "Analysis of pedestrian collision with a pickup truck." Diss., A link to full text of this thesis in SOAR, 2007. http://soar.wichita.edu/dspace/handle/10057/1161.
Full textAbstract:
Thesis (M.S.)--Wichita State University,College of Engineering, Dept. of Mechanical Engineering."May 2007." Title from PDF title page (viewed on Dec. 27, 2007). Thesis adviser: Hamid M. Lankarani. Includes bibliographic references (leaves 76-80).
7
Coltin, Brian. "Multi-Agent Pickup And Delivery Planning With Transfers." Research Showcase @ CMU, 2014. http://repository.cmu.edu/dissertations/376.
Full textAbstract:
In Pickup and Delivery Problems (PDPs), mobile vehicles retrieve and deliver a set of items. The PDP is a well-studied, NP-hard problem. Examples of the PDP include mail and courier services, taxis, ridesharing services, and robots such as our own CoBots and CreBots, which retrieve and deliver items for the occupants of a building, and are the motivation for this thesis. The goal of the PDP is to find a schedule that delivers as many items as possible at the lowest cost, under various constraints such as time windows and vehicle capacities. We augment the PDP with transfers to form the PDP with Transfers (PDP-T). Instead of having a single vehicle retrieve and deliver each item, vehicles can transfer items to other vehicles (or chains of vehicles) for delivery. Allowing transfers makes lower cost solutions feasible, but increases the number of possible schedules exponentially. In this thesis, we contribute a series of algorithms to form schedules for variants of the PDP-T. We introduce the Very Large Neighborhood Search with Transfers (VLNS-T) algorithm to plan schedules for the most general version of the PDP-T, with constraints including time windows, capacities, vehicle start and end locations, maximum item transport times, and maximum vehicle route durations. We also contribute algorithms for simplified variants of the PDP-T, which take advantage of the problem structure to find solutions more quickly and more effectively than the general algorithm for specific PDP-T variants, some with provable guarantees. We also study the challenges of deploying PDP-T schedules on physical robots, and execute PDP-T schedules on the CoBots. The robots reschedule their tasks in response to new requests, delays, failures, and shared information from other robots. We also introduce the CreBots, which transfer items fully autonomously. Our PDP-T algorithms are evaluated on benchmark problems, on the CoBots, and on problems on city maps sampled from real world taxi data, demonstrating that lower cost schedules can be found with transfers.
8
Setiadinata, Sylvester Brian. "Corrosion and hydrogen pickup mechanisms of zirconium alloys." Thesis, University of Oxford, 2016. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.728802.
Full text
9
Wade, Andrew David. "Investigation into road rumble in a light utility vehicle." Thesis, Link to the online version, 2005. http://hdl.handle.net/10019/1297.
Full text
10
Krypczyk, Veikko [Verfasser]. "Nachbarschaftssucheverfahren für dynamische Pickup- und Delivery-Probleme / Veikko Krypczyk." Hagen : Fernuniversität Hagen, 2010. http://d-nb.info/1001671643/34.
Full text
11
Cummings, Charles R. III (Charles Ronald). "Improving the inbound supply chain through dynamic pickup windows." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/90761.
Full textAbstract:
Thesis: M.B.A., Massachusetts Institute of Technology, Sloan School of Management, 2014. In conjunction with the Leaders for Global Operations Program at MIT.Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2014. In conjunction with the Leaders for Global Operations Program at MIT.
Cataloged from PDF version of thesis.
Includes bibliographical references (page 72).
Amazon is one of the world's largest retailers with revenues of $74.5 billion in 2013 and 22% growth over 2012. As Amazon continues to grow and offer greater selection, more products are flowing through an expanding inbound network. While this growth has added complexity for the inbound transportation organization, it has also created opportunities to reduce transportation cost and improve performance. Inbound transportation managed by Amazon currently represents 60% of the company's inbound freight. For this freight, Amazon uses automated shipment-planning systems to select a carrier for all shipments. The systems run once per day, selecting carriers for a set of shipment requests where each vendor has specified a freight ready date of tomorrow. Several inputs are included to achieve a low transportation cost for the network, but the systems are constrained by the vendor's freight ready date. By introducing dynamic pickup windows based on when the freight is needed in the fulfillment centers (FCs), Amazon has the opportunity to reduce transportation cost and mitigate out-of-stock occurrences. A current state analysis revealed that approximately 70% of Amazon's freight was shipped through expensive less-than-truckload and small-parcel methods. While truckload shipments are ideal in transportation, ordering smaller lots more frequently is preferable to maintain high in-stock levels in the FCs while keeping inventory holding costs low. Therefore, Amazon's shipment-planning systems minimize transportation cost by building multi-stop routes to pick up smaller shipments from several vendors before delivering to the FC. The dynamic pickup window solution changes the planning process by relaxing the constraint of tendering a shipment today to a high cost transportation mode if that freight does not need to ship today. If shipment requests are not tendered today and instead sent to tomorrow's pool of requests, two types of consolidation can occur: (1) a single-vendor consolidation and (2) a multi-vendor consolidation. A model was developed to simulate shipment planning on the entire network for one week, resulting in a 2% transportation cost reduction and 4% fewer shipments while protecting in-stock levels. Amazon piloted in late 2013 with success and plans to implement throughout the network in early 2014. While the dynamic pickup window solution is presented with Amazon as the case study, the solution is applicable to any business with stochastic demand and lead time, a large vendor base, and control of managing its inbound transportation.
by Charles R Cummings, III.
M.B.A.
S.M.
12
Capelle, Nuño Thomas Emmanuel. "Problema de localización y ruteo con pickup y delivery." Tesis, Universidad de Chile, 2012. http://www.repositorio.uchile.cl/handle/2250/113031.
Full textAbstract:
Magíster en Ciencias de la Ingeniería, Mención TransporteIngeniero Civil Matemático
El objetivo de esta tesis es formular un modelo que integre el Pickup and Delivery Problem (PDP) y la localización óptima de los depots de distribución, el cual llamaremos Problema de Localización y Ruteo con Pickup and Delivery (PLRPDP). Este problema se plantea y tiene una gran variedad de aplicaciones en la industria, como por ejemplo en el courier, en el transporte de pasajeros, o en el transporte de alimentos perecibles, y por lo tanto es de suma importancia cuando existe un sistema de alta demanda con diferentes opciones en relación a la ubicación de los depots. Para modelar este problema se propone un esquema de generación de columnas, donde el problema maestro resultante es similar al del modelo propuesto por Berger et al. (2007), pero en este caso, el subproblema es un PDP. Para resolver este subproblema y poder generar columnas factibles para el problema maestro, se propone un algoritmo de label-setting, que resuelve el problema de camino más corto, con restricciones de Pickup and Delivery y ventanas de tiempo. Además se propone un conjunto de heurísticas para acelerar este proceso. Para validar el modelo, se hace una implementación del esquema de generación de columnas, el cual se prueba en diferentes instancias, algunas ya existentes en la literatura actual, como también desarrolladas en este trabajo. Destacando dentro de estas últimas, las instancias clusterizadas y las de tipo corredor, las cuales por su geometría especial hacen que la localización de los depots sea de suma importancia. También se hace un análisis detallado de como los costos de apertura de los depots inciden en la solución óptima. Finalmente se presentan resultados del rendimiento de nuestra implementación para cada una de las instancias.
13
Aleksandrov, Martin Damyanov. "Heuristics and policies for online pickup and delivery problems." Master's thesis, Faculdade de Ciências e Tecnologia, 2012. http://hdl.handle.net/10362/8197.
Full textAbstract:
Master ThesisIn the last few decades, increased attention has been dedicated to a speci c subclass of Vehicle Routing Problems due to its signi cant importance in several transportation areas such as taxi companies, courier companies, transportation of people, organ transportation, etc. These problems are characterized by their dynamicity as the demands are, in general, unknown in advance and the corresponding locations are paired. This thesis addresses a version of such Dynamic Pickup and Delivery Problems, motivated by a problem arisen in an Australian courier company, which operates in Sydney, Melbourne and Brisbane, where almost every day more than a thousand transportation orders arrive and need to be accommodated. The rm has a eet of almost two hundred vehicles of various types, mostly operating within the city areas. Thus, whenever new orders arrive at the system the dispatchers face a complex decision regarding the allocation of the new customers within the distribution routes (already existing or new) taking into account a complex multi-level objective function. The thesis thus focuses on the process of learning simple dispatch heuristics, and lays the foundations of a recommendation system able to rank such heuristics. We implemented eight of these, observing di erent characteristics of the current eet and orders. It incorporates an arti cial neural network that is trained on two hundred days of past data, and is supervised by schedules produced by an oracle, Indigo, which is a system able to produce suboptimal solutions to problem instances. The system opens the possibility for many dispatch policies to be implemented that are based on this rule ranking, and helps dispatchers to manage the vehicles of the eet. It also provides results for the human resources required each single day and within the di erent periods of the day. We complement the quite promising results obtained with a discussion on future additions and improvements such as channel eet management, tra c consideration, and learning hyper-heuristics to control simple rule sequences.
The thesis work was partially supported by the National ICT Australia according to the Visitor Research Agreement contract between NICTA and Martin Damyanov Aleksandrov
14
Männel, Dirk [Verfasser]. "Das Pickup and Delivery Problem mit mehrdimensionalen Ladebeschränkungen / Dirk Männel." Magdeburg : Universitätsbibliothek, 2018. http://d-nb.info/1165650460/34.
Full text
15
Rahmani, Younes. "The Multi-product Location-Routing Problem with Pickup and Delivery." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0331/document.
Full textAbstract:
Dans les problèmes de localisation-routage classiques (LRP), il s'agit de combiner des décisions stratégiques liées aux choix des sites à ouvrir (centres de traitement) avec des décisions tactiques et opérationnelles liées à l'affectation des clients aux sites sélectionnés et a la confection des tournées associées. Cette thèse propose de nouveaux modèles de localisation-routage permettant de résoudre des problématiques issues de réseaux logistiques, devenus aujourd'hui de plus en plus complexes vu la nécessité de mutualisation de ressources pour intégrer des contraintes de développement durable et des prix de carburants qui semblent augmenter de manière irrémédiable. Plus précisément, trois aspects ont été intégrés pour généraliser les modèles LRP classiques de la littérature : 1) l'aspect pickup and delivery, 2) l'aspect multi-produits, et 3) la possibilité de visiter un ou plusieurs centres de traitement dans une tournée donnée. Nous avons étudié deux schémas logistiques, qui ont donné lieu à deux nouveaux modèles de localisation et de routage, le MPLRP-PD (LRP with multi-product and pickup and delivery), qui peut être vu comme une extension des problèmes de tournées de véhicules avec collecte et livraison, intégrant une décision tactique liée à la localisation des centres de traitement (noeud avec collecte et livraison) dans un réseau de distribution à un seul échelon, et le 2E-MPLRP-PD (Two-echelon LRP with multi-product and pickup and delivery) qui est une généralisation du LRP à deux échelons avec les contraintes citées plus-haut. Ces deux modèles ont été formalisés par des programmes linéaires en variables mixtes (MIP). Des techniques de résolution, basées sur des méthodes de type heuristique, clustering, métaheuristique, ont été proposées pour résoudre le MPLRP-PD et le 2E-MPLRP-PD. Les jeux d'essais de la littérature ont été généralisés pour tester et valider les algorithmes proposésIn the framework of Location-Routing Problem (LRP), the main idea is to combine strategic decisions related to the choice of processing centers with tactical and operational decisions related to the allocation of customers to selected processing centers and computing the associated routes. This thesis proposes a new location-routing model to solve problems which are coming from logistics networks, that became nowadays increasingly complex due to the need of resources sharing, in order to integrate the constraints of sustainable development and fuels price, which is increasing irreversibly. More precisely, three aspects have been integrated to generalize the classical LRP models already existed in the literature: 1) pickup and delivery aspect, 2) multi-product aspect, and 3) the possibility to use the processing centers as intermediate facilities in routes. We studied two logistics schemes gives us two new location-routing models: (i) MPLRP-PD (Multi-product LRP with pickup and delivery), which can be viewed as an extension of the vehicle routing problem with pick-up and delivery, including a tactical decision related to the location of processing centers (node with pick-up and delivery), and (ii) 2E-MPLRP-PD (Two-echelon multi-product LRP with pickup and delivery), which is a generalization of the two-echelon LRP. Both models were formalized by mixed integer linear programming (MIP). Solving techniques, based on heuristic methods, clustering approach and meta-heuristic techniques have been proposed to solve the MPLRP-PD and the 2E-MPLRP-PD. The benchmarks from the literature were generalized to test and to validate the proposed algorithms
16
Doerner, Karl, Richard F. Hartl, and Marc Reimann. "Ant colony optimization applied to the pickup and delivery problem." SFB Adaptive Information Systems and Modelling in Economics and Management Science, WU Vienna University of Economics and Business, 2000. http://epub.wu.ac.at/1434/1/document.pdf.
Full textAbstract:
In this paper we propose an ACO algorithm to optimize the total costs associated with the pickup and delivery of full truckloads under time window constraints in a hub network. We perform a thorough technical analysis of the ACO by comparing different pheromone decoding schemes, different visibility information and various population sizes. Furthermore we propose a post-optimization technique to improve the solutions. Our results show that appropriate data structures significantly improve the solution quality.Series: Working Papers SFB "Adaptive Information Systems and Modelling in Economics and Management Science"
17
Nakao, Yoshitaka. "Studies on Algorithms and Analyses for Pickup and Delivery Problems." 京都大学 (Kyoto University), 2010. http://hdl.handle.net/2433/108367.
Full text
18
Chaichiratikul, Pairoj. "Hybrid metaheuristics for solving multi-depot pickup and delivery problems." Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/30647.
Full textAbstract:
In today's logistics businesses, increasing petrol prices, fierce competition, dynamic business environments and volume volatility put pressure on logistics service providers (LSPs) or third party logistics providers (3PLs) to be efficient, differentiated, adaptive, and horizontally collaborative in order to survive and remain competitive. In this climate, efficient computerised-decision support tools play an essential role. Especially, for freight transportation, e efficiently solving a Pickup and Delivery Problem (PDP) and its variants by an optimisation engine is the core capability required in making operational planning and decisions. For PDPs, it is required to determine minimum-cost routes to serve a number of requests, each associated with paired pickup and delivery points. A robust solution method for solving PDPs is crucial to the success of implementing decision support tools, which are integrated with Geographic Information System (GIS) and Fleet Telematics so that the flexibility, agility, visibility and transparency are fulfilled. If these tools are effectively implemented, competitive advantage can be gained in the area of cost leadership and service differentiation. In this research, variants of PDPs, which multiple depots or providers are considered, are investigated. These are so called Multi-depot Pickup and Delivery Problems (MDPDPs). To increase geographical coverage, continue growth and encourage horizontal collaboration, efficiently solving the MDPDPs is vital to operational planning and its total costs. This research deals with designing optimisation algorithms for solving a variety of real-world applications. Mixed Integer Linear Programming (MILP) formulations of the MDPDPs are presented. Due to being NP-hard, the computational time for solving by exact methods becomes prohibitive. Several metaheuristics and hybrid metaheuristics are investigated in this thesis. The extensive computational experiments are carried out to demonstrate their speed, preciseness and robustness.
19
Drews, Christian [Verfasser]. "Interstellar Pickup Ions at 1 AU with STEREO/PLASTIC / Christian Drews." Kiel : Universitätsbibliothek Kiel, 2013. http://d-nb.info/1035405539/34.
Full text
20
Wohlgemuth, Sascha. "Traffic information and dynamic pickup and delivery planning in forwarding agencies." Dortmund Verl. Praxiswissen, 2010. http://d-nb.info/100080853X/04.
Full text
21
Nguyen, John, and Kasper Lindén. "Creating a Back Stock to Increase Order Delivery and Pickup Availability." Thesis, KTH, Hälsoinformatik och logistik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-252798.
Full textAbstract:
Apotek Hjärtat wants to keep developing their e-commerce website and improve retrieval and delivery of orders to customers. Click and Collect and Click and Express are two options for retrieving e-commerce orders that are available if all products in the order are present in the store. By implementing a back stock in the stores with popular e-commercial items, all products of an order will more often be present in the store. The back stock will in such a way increase the availability of Click and Collect and Click and Express. The goals for the study are to conduct a pilot study, compare methods and possible solutions to implement a model to reach the goals. The pilot study was made by studying previous works in mathematical statistics methods and machine learning methods. The statistical method was accomplished through the analytical tool Statistical Package for the Social Sciences (SPSS) and Java. The machine learning method was accomplished through Python and the Scikit-learn library. The machine learning method was performed by a regression algorithm that was used to find relations between category sales and pollen forecasts. The statistical and machine learning methods were compared to each other. Both gave identical results, but the machine learning method was more functional and easier to further develop and consequently was chosen. Several models were created for a few selected product categories. The categories that did not work for the models had an unrealistic amount of sold products. These amounts could be negative or extremely high when unknown inputs were introduced. A simulation was made of the back stock to estimate how it would increase the availability of Click and Collect/Click and Express. The machine learning models could need more data for more accurate predictions. A conclusion could be made though that is possible to predict the amount of sold products of certain categories such as Allergy and Child Medicine with pollen halt taken into account.Apotek Hjärtat vill fortsätta utveckla sin e-handelssida och förbättra upphämtning och leverans av ordrar till kund. Click and Collect och Click and Express är två val för att hämta upp e-handelsordrar som finns tillgängliga om alla produkter i ordern finns i butik. Genom att implementera ett baklager i butiker med populära unika ehandelsprodukter kommer alla produkter i en order oftare att finnas i butik. Baklagret kommer på så vis öka tillgängligheten av Click and Collect och Click and Express. Målen är att utföra en förstudie, samt att jämföra och hitta en bra lösning att implementera en modell för att uppnå målen. Förstudien gick ut på att analysera tidigare arbeten inom matematiska statistikmetoder och maskininlärningsmetoder. Den statistiska metoden utfördes genom det analytiska verktyget Statistical Package for the Social Sciences (SPSS) och Java. Maskininlärningsmetoden utvecklades med hjälp av Python och Scikit-learn biblioteket. Maskinlärningsmetoden utfördes genom en regressionsalgoritm som användes för att ta fram flera modeller för relationer mellan försäljning av kategorier och pollenprognoser. Statistiska metoden och maskininlärningsmetoden jämfördes med varandra. Båda gav identiska resultat men maskininlärning var mer funktionellt och enklare att vidareutveckla och därför valdes den metoden. Flera olika modeller lyckades tas fram för en del produktkategorier. De kategorier som inte fungerade för modellerna hade orealistiska mängder sålda varor. Dessa mängder kunde vara negativa eller extremt höga när okända inputs introducerades. Med hjälp av simulationen var det möjligt att uppskatta hur baklagret skulle öka tillgängligheten av Click and Collect/Express. Maskininlärningsmodellerna skulle behöva mer data, som kommer i framtiden, för att ge en mer precis prediktering mellan pollenvärden. Som slutsats är det möjligt att använda dem i framtiden för vissa kategorier som allergi och barnmedicin.
22
Gonul, Bulent. "Extended adiabatic treatments of continuum channels in nuclear stripping pickup reactions." Thesis, University of Surrey, 1994. http://epubs.surrey.ac.uk/844378/.
Full textAbstract:
Although the quasi-adiabatic calculations have led to an improved description of the measured observables, the theoretical justifications of the assumptions made in the model have not yet been studied. The first part of the work described in this thesis is therefore concerned with the clarification of these theoretical uncertainties by performing a rigorous investigation of the accuracy and the validity of the model. In addition, we reformulate the quasi-adiabatic theory to give a more general formalism, approaching the three-body problem in a different way. This alternative formulation provides a clear understanding of the assumptions made in the original quasi-adiabatic theory. Using the spirit of the new quasi-adiabatic formalism, we also develop alternative approximation schemes for the treatment of quantum mechanical three-body systems. The accuracy and the range of validity of the developments, together with the quasi-adiabatic theory, are investigated carefully and precisely by comparing their predictions with those essentially exact CDCC technique for the 66Zn (d,p)67Zn reaction at 88.2 MeV. It is found that the alternative models and quasi-adiabatic theory are reliable techniques for the treatment of deuteron breakup process at intermediate energies of interest. The remainder of this thesis is devoted to the investigation of the mechanism of (p,d*) reactions. As the treatment of the final state interactions in such reactions has not previously been studied consistently, we develop an adiabatic method and apply it to new data for the 13C(p,d)12C reaction with 35 MeV incident proton energy. Due to the weak coupling between spin channels of the continuum n-p system at the energies of interest, the singlet and triplet state pickup cross-sections for the final n-p system are analyzed separately. We find that the contribution from the singlet state is dominant for small relative energies while the triplet state dominates for large energies. This application clarifies the relationship between the three-body dynamics in the final state of (p,d) and (p,d*) reactions.
23
Tangirala, Shubha S. "Applicability of semi-tension fields to the back panel of a pick-up truck." Master's thesis, Mississippi State : Mississippi State University, 2003. http://library.msstate.edu/etd/show.asp?etd=etd-11032003-133823.
Full text
24
Ivanović, Goran Gue Kevin R. "Aisle designs for unit-load warehouses with multiple pickup and deposit points." Auburn, Ala., 2007. http://repo.lib.auburn.edu/2007%20Fall%20Theses/Ivanovic_Goran_16.pdf.
Full text
25
Hosny, Manar Ibrahim. "Investigating heuristic and meta-heuristic algorithms for solving pickup and delivery problems." Thesis, Cardiff University, 2010. http://orca.cf.ac.uk/55181/.
Full textAbstract:
The development of effective decision support tools that can be adopted in the transportation industry is vital in the world we live in today, since it can lead to substantial cost reduction and efficient resource consumption. Solving the Vehicle Routing Problem (VRP) and its related variants is at the heart of scientific research for optimizing logistic planning. One important variant of the VRP is the Pickup and Delivery Problem (PDP). In the PDP, it is generally required to find one or more minimum cost routes to serve a number of customers, where two types of services may be performed at a customer location, a pickup or a delivery. Applications of the PDP are frequently encountered in every day transportation and logistic services, and the problem is likely to assume even greater prominence in the future, due to the increase in e-commerce and Internet shopping. In this research we considered two particular variants of the PDP, the Pickup and Delivery Problem with Time Windows (PDPTW), and the One-commodity Pickup and Delivery Problem (1-PDP). In both problems, the total transportation cost should be minimized, without violating a number of pre-specified problem constraints. In our research, we investigate heuristic and meta-heuristic approaches for solving the selected PDP variants. Unlike previous research in this area, though, we try to focus on handling the difficult problem constraints in a simple and effective way, without complicating the overall solution methodology. Two main aspects of the solution algorithm are directed to achieve this goal, the solution representation and the neighbourhood moves. Based on this perception, we tailored a number of heuristic and meta-heuristic algorithms for solving our problems. Among these algorithms are: Genetic Algorithms, Simulated Annealing, Hill Climbing and Variable Neighbourhood Search. In general, the findings of the research indicate the success of our approach in handling the difficult problem constraints and devising simple and robust solution mechanisms that can be integrated with vehicle routing optimization tools and used in a variety of real world applications
26
Chuah, Keng Hoo. "OPTIMIZATION AND SIMULATION OF JUST-IN-TIME SUPPLY PICKUP AND DELIVERY SYSTEMS." UKnowledge, 2004. http://uknowledge.uky.edu/gradschool_diss/384.
Full textAbstract:
A just-in-time supply pickup and delivery system (JSS) manages the logistic operations between a manufacturing plant and its suppliers by controlling the sequence, timing, and frequency of container pickups and parts deliveries, thereby coordinating internal conveyance, external conveyance, and the operation of cross-docking facilities. The system is important to just-in-time production lines that maintain small inventories. This research studies the logistics, supply chain, and production control of JSS. First, a new meta-heuristics approach (taboo search) is developed to solve a general frequency routing (GFR) problem that has been formulated in this dissertation with five types of constraints: flow, space, load, time, and heijunka. Also, a formulation for cross-dock routing (CDR) has been created and solved. Second, seven issues concerning the structure of JSS systems that employ the previously studied common frequency routing (CFR) problem (Chuah and Yingling, in press) are explored to understand their impacts on operational costs of the system. Finally, a discreteevent simulation model is developed to study JSS by looking at different types of variations in demand and studying their impacts on the stability of inventory levels in the system. The results show that GFR routes at high frequencies do not have common frequencies in the solution. There are some common frequencies at medium frequencies and none at low frequency, where effectively the problem is simply a vehicle routing problem (VRP) with time windows. CDR is an extension of VRP-type problems that can be solved quickly with meta-heuristic approaches. GFR, CDR, and CFR are practical routing strategies for JSS with taboo search or other types of meta-heuristics as solvers. By comparing GFR and CFR solutions to the same problems, it is shown that the impacts of CFR restrictions on cost are minimal and in many cases so small as to make simplier CFR routes desirable. The studies of JSS structural features on the operating costs of JSS systems under the assumption of CFR routes yielded interesting results. First, when suppliers are clustered, the routes become more efficient at mid-level, but not high or low, frequencies. Second, the cost increases with the number of suppliers. Third, negotiating broad time windows with suppliers is important for cost control in JSS systems. Fourth, an increase or decrease in production volumes uniformly shifts the solutions cost versus frequency curve. Fifth, increased vehicle capacity is important in reducing costs at low and medium frequencies but far less important at high frequencies. Lastly, load distributions among the suppliers are not important determinants of transportation costs as long as the average loads remain the same. Finally, a one-supplier, one-part-source simulation model shows that the systems inventory level tends to be sticky to the reordering level. JSS is very stable, but it requires reliable transportation to perform well. The impact to changes in kanban levels (e.g., as might occur between route planning intervals when production rates are adjusted) is relatively long term with dynamic after-effects on inventory levels that take a long time to dissapate. A gradual change in kanban levels may be introduced, prior to the changeover, to counter this effect.
27
Lau, Shuk-kwan, and 劉淑君. "An immunological approach to rolling horizon order pickup scheduling for AS/RSs." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2010. http://hub.hku.hk/bib/B4440668X.
Full text
28
Clemens, A. J. "Pickup ion processes associated with spacecraft thrusters : implications for solar probe plus." Thesis, Queen Mary, University of London, 2016. http://qmro.qmul.ac.uk/xmlui/handle/123456789/18424.
Full textAbstract:
Chemical thrusters are widely used in spacecraft for attitude control and orbital manoeuvres. They produce a plume of neutral gas which produces ions via photoionisation and charge exchange. Measurements of local plasma properties will be aff ected by perturbations caused by the coupling between the newborn ions and the plasma. A model of neutral expansion has been used in conjunction with a fully three-dimensional hybrid code to study the evolution and ionisation over time of the neutral cloud produced by the ring of a mono-propellant hydrazine thruster as well as the interactions of the resulting ion cloud with the ambient solar wind. A parameter survey was performed for varying angles of injection and injection rates, particle kinetics were also investigated. Results are presented which show that the plasma in the region near to the spacecraft will be perturbed for an extended period of time with the formation of an interaction region around the spacecraft, a moderate amplitude density bow wave bounding the interaction region and evidence of an instability at the forefront of the interaction region which causes clumps of ions to be ejected from the main ion cloud quasi periodically and the ways in which these features are modifi ed by the degree of solar wind mass loading and the relative orientation of the magnetic fi eld to the angle of injection. This may a ffect Solar Probe Plus for a signifi cant duration as data taking and delicate sensory equipment may be required to cease operation until local fluctuations return to a more moderate level. The scale of the fluctuations seen are dependent upon the duration of the thruster ring and the speci fic geometry and therefore e ffects may vary in-situ.
29
Lilly, Mary. "'The World is Not a Safe Place for Men': The Representational Politics of the Manosphere." Thesis, Université d'Ottawa / University of Ottawa, 2016. http://hdl.handle.net/10393/35055.
Full textAbstract:
This thesis offers an overview of the representational politics of the online antifeminist community known as the ‘manosphere’. It analyzes how gender and gender politics are represented in the discourse, with an eye to how traditional gender constructs, and traditional gendered norms and inequalities, are reproduced.
This project—the first study to focus exclusively on the manosphere—contributes to our understanding of the community in two ways; it addresses a significant gap in the literature on the topic, and it tests the accuracy of the ‘conventional wisdom’ on the manosphere.
Using mixed-methods critical discourse analysis, the study analyzed the discourse of the two primary subcultures of the community, and found that traditional gender norms and relations are reproduced therein, and that for the most part the conventional wisdom is accurate: femininity and women are disparaged, masculinity is imagined to be ‘in crisis’ (constantly under siege by feminizing forces), and feminism is represented as hypocritical and oppressive.
30
Björklund, Erik, Ola Hammarstedt, and Albert Linder. "Optisk gitarr-pickup." Thesis, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-295907.
Full textAbstract:
Målet med projektet är att med ljus läsa av vibrationer i en sträng och omvandla dessatill en elektrisk signal. Detta gjordes med en uppställning bestående av fiberoptik förledande av ljuset, en komponent baserad på en fotodiod, en serie filter samt enoperationsförstärkare. Resultatet blev en utsignal som kunde kopplas direkt i engitarrförstärkare.
31
HUANG, CHIN-TIEN, and 黃金殿. "Smart Tennis Pickup Car." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/w758xd.
Full textAbstract:
碩士崑山科技大學
電機工程研究所
106
In this thesis, the "Smart Tennis Pickup Car" can be paired with a tennis ball service machine, which used to gather a number of tennis on the court, to reduce during training that because of picking up the ball interrupted training and waste of time and physical strength. “Smart Tennis Pickup Car” has a "smart", "human-computer interaction" function. Combined with modern electronic intelligence, object follow, image recognition technology, PWM function, self-walking obstacle avoidance mode and PS2 joystick remote control function. Real-time image recognition of the position of the tennis, and then through the micro-computer controller for computing, control board output instructions, which drives tennis ball pickup car, which executed the tennis collection task. And when it reaches a certain number, it would back to the fixed position, and empty the collection box of tennis. Until the next start signal, it performed the pickup task again. The remote control method can be also used to pickup the tennis.
32
Liao, Jyun-you, and 廖俊宥. "A Study of Pickup and Delivery Problem with Single Pickup to Multiple Delivery." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/90070250103287832093.
Full textAbstract:
碩士國立雲林科技大學
工業工程與管理研究所碩士班
100
The pickup and delivery problem is a special type of vehicle routing problem. This study relaxes a constraint of PDP: a single pickup can deliver to multiple customers in the same route. First, we construct a mathematical model to minimize the travel distance. A solution algorithm based on Simulated Annealing heuristic is then developed to solve the problem. Results of numerical example show that internal exchange within route is better than external exchange between routes. After Sensitivity analysis, also conclude that (1) the higher ratio of single pickup to single customer, the more improvement can be reached. (2)The optimal working time can be evaluated. (3)The near optimal location for depot can also be suggested by the proposed model and solution algorithm.
33
Yang, Chia-Feng, and 楊家逢. "Design of dual-wavelength compatible pickup head and the application of pickup head in angular measurement." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/82186172034602900671.
Full textAbstract:
碩士國立中央大學
光電科學研究所
95
This thesis studies the design of dual-wavelength compatible pickup head and the new application of pickup head applied in angular measurement. In the first part, a design of dual-wavelength compatible pickup head is demonstrated. By using two cubic beam splitters, the optical path length of DVD systems is aligned to that of the CD system. This design would simplify the alignment and arise the optical quality. Also by combined on silicon optical bench, the pickup head can be compatized. The wavefront error, tolerance and operation demand of the pickup head will be analyzed. In the later part of the thesis, the optical system of two different kinds of pickup head will be simulated. By defining two operating signal from photodetectors, the relationship between signal and tilt angle will be studied. Besides, one of the two simulated pickup heads is that applied in atomic force microscope while another one is simulated to find out the difference.
34
Liao, Keng-Hsiang, and 廖更祥. "Planar Position Measurement with Optical Pickup." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/59534972668359826315.
Full textAbstract:
碩士國立交通大學
機械工程系
87
In the field of industry, the engineer often confronts with problems demanded with transducers for position, velocity, and acceleration of the object. In the thesis, we present a method for measuring plane position with a commercially available compact disc optical pickup. The method is used the tracking error signal generated by the optical pick-up head during tracking to count the track numbers. Thus, the distance which the pick-up head has been moved, and the position of the pick-up head can be measured. When the object is doing translation, we only need two pick-up heads to measure the displacement and the position of the object. But if the motion of the object is not only the translation but also the rotation, two pick-up heads are not enough for us to measure. Thus, we need three optical pick-up heads. The displacement of the pick-up head can be measured to calculate the actual displacement and rotation angles of the object. The distance of track is 1.6 , hence, the accuracy of the positioning system is achieved to 1.6 . In this implement we can measure displacement of pickup set which rotation less 90-degree.
35
Qu, Yuan Ph D. "Pickup and delivery problems with side constraints." 2012. http://hdl.handle.net/2152/19531.
Full textAbstract:
Pickup and delivery problems (PDPs) have been studied extensively in past decades. A wide variety of research exits on both exact algorithms and heuristics for generic variations of the problem as well as real-life applications, which continue to spark new challenges and open up new opportunities for researchers. In this dissertation, we study two variations of pickup and delivery problem that arise in industry and develop new computational methods that are shown to be effective with respect to existing algorithms and scheduling procedures found in practice.
The first problem is the pickup and delivery problem with transshipment (PDPT). The work presented here was inspired by a daily route planning problem at a regional air carrier. In structuring the analysis, we describe a unique way to model the transshipment option on a directed graph. With the graph as the foundation, we implemented a branch and price algorithm. Preliminary results showed that it has difficulty in solving large instances. As an alternative, we developed a greedy randomized adaptive search procedure (GRASP) with several novel features. In the construction phase, shipment requests are inserted into routes until all demand is satisfied or no feasible insertion exists. In the improvement phase, an adaptive large neighborhood search algorithm is used to reconstruct portions of the feasible routes. Specialized removal and insertion heuristics were designed for this purpose. We also developed a procedure for generating problem instances in the absence of any in the literature. Testing was done on existing PDP data sets and generated PDPT data set. For the former, the performance and solution quality of the GRASP were comparable to the best known heuristics. For the latter, GRASP found the near optimal solution in most test cases.
In the second part of the dissertation, we focus on a new version of the heterogeneous PDP in which the capacity of each vehicle can be modified by reconfiguring its interior to satisfy different types of customer demands. The work was motivated by a daily route planning problem arising at a senior activity center. A fleet of configurable vans is available each day to transport participants to and from the center as well as to secondary facilities for rehabilitative and medical treatment. To find solutions, we developed a two-phase heuristic that makes use of ideas from greedy randomized adaptive search procedures with multiple starts. In phase I, a set of good feasible solutions is constructed using a series of randomized procedures. A representative subset of those solutions is selected as candidates for improvement by solving a max diversity problem. In phase II, an adaptive large neighborhood search (ALNS) heuristic is used to find local optima by reconstructing portions of the feasible routes. Also, a specialized route feasibility check with vehicle type reassignment is introduced to take full advantage of the heterogeneous nature of vehicles. The effectiveness of the proposed methodology is demonstrated by comparing the solutions it provided for the equivalent of several weeks with those that were used in practice and derived manually. The analysis indicates that anywhere from 30% to 40% savings can be achieved with the multi-start ALNS heuristic.
An exact method is introduced based on branch and price and cut for settings with more restricted time windows. In the procedure, the master problem at each node in the search tree is solved by column generation to find a lower bound. To improve the bound, subset-row inequalities are applied to the variables of the master problem. Columns are generated by solving the pricing subproblems with a labeling algorithm enhanced by new dominance conditions. Local search on the columns is used to quickly find promising alternatives. Implementation details and ways to improve the performance of the overall procedure are discussed. Testing was done on a set of real instances as well as a set of randomly generated instances with up to 50 customer requests. The results show that optimal solutions are obtained in majority of cases.text
36
Chang, Yu-Cheng, and 張育誠. "Optical Element of Micro-Optical Pickup Head." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/97208650079957687607.
Full textAbstract:
碩士國立中央大學
光電科學研究所
91
A new optical pickup head is introduced, with its optical components fabricated by the microoptoelectromechanical (MOEMS) technology. Optical elements, such as grating, holographic optical element and Fresnel lens, are made on the SiN membrane. The SiN film was deposited on the silicon wafer by low pressure chemical vapor deposition (LPCVD) or plasma enhanced chemical vapor deposition (PECVD). Its advantages include the high transmission efficiency, light weight, and easy packaging for this new proposed optical pickup head.
37
Narkhede, Sachin Narayan. "Analysis of pedestrian collision with a pickup truck." Thesis, 2007. http://hdl.handle.net/10057/1161.
Full textAbstract:
During the last two decades, changes in vehicle design and increase in the number of the light truck vehicles (LTVs) and vans have led to changes in pedestrian injury profile. Due to the dynamic nature of the pedestrian crashes, biomechanical aspects of collisions can be better evaluated in field studies. Thousands of pedestrians are killed or injured in road traffic accidents. The need to provide and improve pedestrian crash survival research programs in pedestrian collision environment is the subject of much interest and research. At present, the European Enhanced Vehicle-safety Committee (EEVC) test procedure for impacts of various pedestrian subsystems, which represent sections of the human body, provides a means of assessing and rating the impact sites on a vehicle. Development and evaluation of test procedures, such as “ull-body analysis” with the aid of computer simulation for optimizing vehicles on computer for compliance with the testing and evaluation methods proposed by the EEVC, which assess the injury propensity of vehicle structures for pedestrians is needed. The TNO Road Vehicle Research Institute has adopted a fully integrated approach of “ull-body analysis,” which offers a significant advantage over the EEVC method that the entire body of the pedestrian can be considered, including interactions between the individual parts of the body. The purpose of this study is to reconstruct a pedestrian-vehicle accident case by dummy model simulation to provide a way to study the kinematics and potential injuries of pedestrian in any specific impact situation. Study provides flexibility to manipulate model parameters to capture impact responses of the pedestrian. The simulations are carried out at three different dummy positions: side, front and rear. Impact speed, vehicle front shapes, stiffness of vehicle parts and pedestrian height are the key factors, which influence the pedestrian kinematics and injury severity in a pedestrian-vehicle impact. It is most important to evaluate head injury risks as it causes a serious threat to life. Pedestrian-vehicle crash simulations are studied at different impact speeds to replicate accidents involving adult and child pedestrians. These studies are done for the light pickup truck. The overall pedestrian behavior, head impact events to predict possible head impact location and injuries sustained by head, chest and pelvis are determined. There is a correlation between the pedestrian height and the head impact location. The 6-year old child is more liable to chest injury in impacts with truck. The potential injury to chest and pelvis is more for the child pedestrians in accidents. In general, the injuries sustained by head, chest and pelvis are severe for the high speed crashes since the resultant body velocities are high during post impact kinematics. The research also postulates a method for development of pedestrian compliant vehicle structure to minimize the potential injury riskThesis (M.S.)--Wichita State University, College of Engineering, Dept. of Mechanical Engineering.
38
Li, Chi-feng, and 李奇峰. "Application of Diffractive Elements to Micro Pickup Head." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/77586777070756870195.
Full textAbstract:
碩士國立臺灣科技大學
電子工程系
95
The objective of this thesis is to discuss the microfabrication of three kinds of diffractive optical elements, namely, collimator, beam splitter, and astigmatic lens. Multilevel structures quantized from continuous surface relief can be fabricated with semiconductor manufacturing technology. The purpose is to integrate all the diffractive elements with multilevel structures into the optical system on the silicon for a miniatured pickup head, which has the advantages of compact form factor, light weight and low cost. The surface structures of a phase diffractive optical elements can modify laser beams into a specified patterns and proveide new optical functions for specific industrial application. However, the diffractive optical elements are highly sensitive to the errors of microfabrication. The errors of mask alignment, etching and linewidth have significant influence on the optical functions of elements. The paper shows the results of measurement with AFM, SEM and efficiency of the diffractive optical elements. At last, a fan-out element has been chosen to carry out tolerance analysis on alignment errors, etching errors and linewidth errors by using G-Solver software.
39
Yanti, Lili, and 林碧莉. "A Pickup and Delivery Problem with Hub-Exchange." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/85701442563909646668.
Full textAbstract:
碩士國立臺灣大學
工業工程學研究所
99
The innovation study of Pickup and Delivery Problem (PDP) is to implement Hub-Exchange in handling the Urgent Transfer of Medical Record folders in Hospital. The urgent transfer process from one department to another is necessary for patients who visit more than one department in one day. The Hub-Exchange procedure may reduce the Couriers'' workload and Patients'' waiting time simultaneously. Hub exchange is the activity when couriers doing the transshipment exchange folders for far regions with another courier in Hub/depot. The comparison between existing procedure (Policy I) and Hub-Exchange procedure (Policy II) is based on 3 different time periods in one month data for representing different levels of couriers’ workload. The comparison makes use of the heuristics methods of Nearest Neighbor Algorithm. The simulation running 30 minute time interval and the request data will be divided into three groups of couriers’ territory. The route starts from depot and return to depot after completing the job. There are different estimation methods of Complete Tour and Waiting Time calculation between Policy I and Policy II. As the result of Hub-Exchange procedure increases the working efficiency between couriers, which shown by the workload more evenly, decreased of couriers’ workload, and the shorter time needed to complete the job.
40
Yeh, Yu-Hsuan, and 葉雨璇. "Simultaneous Pickup and Delivery Problem with Parcel Lockers." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/68hrn7.
Full textAbstract:
碩士國立臺灣科技大學
工業管理系
107
In the past three decades, E-commerce market has developed rapidly. Urban logistics has become an enabler of E-commerce development which led to the importance of last mile delivery efficiency. As customers expect timely and accurate delivery of online shopping purchase, this brings new challenges for last mile delivery. In a case when the goods are delivered to the customers but are not received, the goods must be carried back to the warehouse, stored; and in effect, accrues an additional cost. To deal with this problem, parcel lockers systems and convenient stores are launched to serve as pick-up and payment stations. The said system allows round-the-clock service, flexibility on location and schedule of pickup and delivery. This research investigates the end-to-end process of delivering the goods from the retailer's warehouse to the customers with a change of the delivery mode in the last mile. This research extends the Vehicle Routing Problem with Parcel Lockers (VRPPL) and proposes the Simultaneous Pickup and Delivery Problem with Parcel Lockers (SPDPPL) to complement real-world scenario. This research formulates a mathematical model and proposes a simulated annealing (SA) algorithm for solving SPDPPL to minimize total traveling cost. The results were compared to instances of simultaneous delivery and pickup problem with time windows (SDPPTW) from Wang and Chen’s benchmark. A new set of SPDPPL instances which was modified from SDPPTW instances was generated for this model. The results from designed SA were better in computational time and optimality compared to Gurobi.
41
Lin, Hsin-Hsien, and 林欣賢. "Latch-Up Check For well pickup/device coverage." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/44fggy.
Full textAbstract:
碩士明道大學
管理研究所
95
Latch up check, especially the pickup (or tie)/device coverage, has become an important check in most leading edge technology. The rule requires that all devices in a well should be covered by a pickup within a specified distance. It is used to check the electrical integrity of wells. This paper is mainly a part designed on the chip design, carry on the effect inspection of latch-up. Expected to use and build the way to construct DT (Delaunay triangulation ) , will avoid the latch-up effect through the operation of the procedure soon during the course of designing, reduce the probability that the integrated chip is damaged . And accede to and study different rules similarly before in the course of experiment , by improving the efficiency and way checked. The major contribution of this paper is to check latch-up correctly, and improve the efficiency checked and efficiency of improving operation. Because limited to the restriction of the equipment, this research is only a discussion which performs the algorithm, not the operation on the real chip.
42
Tsai, Yi-Chen, and 蔡宜絹. "Application of Micro Device for DVD-like Pickup." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/86110117868095345835.
Full textAbstract:
碩士國立交通大學
光電工程所
91
Optical data storage industries are continually growing with rapid progress of computer, multimedia, and network markets. In this trend, technologies capable of recording more information thus become increasingly demanded. Optical pickups are key component of the recording system. To develop high-spatial-resolution, high-optical-efficiency, and small-sized optical pickup is essential to enable the system more competitive in price and performance. Among these optical devices in the optical pickup, the objective lens is the most important device. From DVD specification, such as the cover layer thickness and the three beam tracking, the minimum size of objective lens was discussed. Moreover, to fabricate the micro lens applied to objective lens, the mature processes to for micro devices are reflow process and gray-scale mask. The spherical lens made by using the reflow processes causes the spherical aberrations. Therefore, the reflow process is not feasible to make the lenses satisfied the DVD specification. The other approach to make the micro objective lenses is the gray-scale mask. By well-adjusted aperture ratio of the mask, the aspheric surface which has eliminated geometrical aberration is feasible. Therefore, we suggest using gray-scale mask to fabricate micro lenses. With this process, three kinds of lenses, namely aspheric lens, Fresnel lens, and harmonic lens are feasible. By utilizing proper optimization variables, the aspheric lenses with thickness of 97.5 μm meet the requirement of DVD-like objective lens. However, the thickness of the aspheric lens is too thick to be fabricated. Next, the Fresnel lens was proposed to overcome the thickness. Nevertheless, the 1um line width of the Fresnel lens is too fine to make the refractive profile for a lens of high NA. Thus, we propose the harmonic lens for objective lens purpose. The conventional design steps of harmonic lens include three parts. First, the refractive profile was designed. Next, the refractive profile was sliced. Finally, the sliced layers were compressed into one layer. The focal shift of slicing induces the aberrations. We proposed a novel method to overcome this issue. When slicing the lens, we employed the aspheric profile to redesign the surface of each segment and choice the outmost part with eliminated geometrical aberration. The redesigned harmonic lens obtained is the combination of several segments with aspheric profiles. The thickness of the redesigned harmonic lens is 19.5 μm. The diameter of designed harmonic lens is 260 μm to couple three-beams tracking with beam width of 210 μm. The volume of the objective lens is highly reduced to 1.9110-6 cm3. A harmonic diffractive objective lens has been designed to be fabricated with gray-scale mask photolithography and will be integrated onto a free space optical module for a MEMS-type DVD-like pickup. The modeling and analysis show that the aberration of objective lens is negligible and the size of focused spot meets DVD specification of 1.08 μm.
43
Tai, Chia-ping, and 戴佳萍. "Analyses of the High-NA Optical Pickup Readout." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/55506880589196632636.
Full textAbstract:
碩士國立交通大學
光電工程所
88
In optical recording, the solid immersion lens (SIL) is designed to have the higher numerical aperture (NA) of the optical system, thus to increase the areal recording density. The modeling based on the vector nature is proposed to clarify the behavior of electromagnetic waves in such optics and manifest the inevitability to correct the conventionally used scalar diffraction model. According to the vector model, the spot size in the air gap is about 210 nm for NA=1.6 and 395 nm for NA=0.8. The polarization effect is also examined to identify the difference derived from scalar and vector calculations. The spot size changes to 250 nm on the recording layer for NA=1.6 and 407 nm for NA=0.8. The enlargement of the spot size is more severe for high-NA system, i.e. the depth of focus is reduced, which can limit such near-field optics in practical usage. In signal readout, the higher signal modulation and cut-off frequency is obtained in the high-NA system. This ensures the reading of the data from high-density optical disk. Besides, a useful technique based on using a simple opaque optical filter in the collection path is also introduced to improve the resolution. According to the results of simulation, the higher modulation is still obtained in the high-NA system as the filter is added and also the equalization of the signal is more efficient. When the width of the shading band in the filter becomes larger, more reflected signal is blocked. Though the efficiency of the equalization effect becomes increased, the ratio of the noise from the electronics to the signal intensity is also increased. Thus, the balance between the quality of the readout signal and the ratio of noise should be carefully traded-off.
44
Huang, Dai-Tin, and 黃戴廷. "Design of a Novel Optical Pickup Head Actuator." Thesis, 1999. http://ndltd.ncl.edu.tw/handle/04437687537038474090.
Full textAbstract:
碩士國立清華大學
動力機械工程學系
87
This research presents a novel design of the optical pickup head actuator for improving the performance deficiencies due to its heavy mass and large volume. Different from the pickup head of current optical disc drives, the coils and magnets are arranged along the axial direction for the purpose of space saving. The proposed prototype possesses the advantages, such as lighter, smaller, thinner, and less components. Furthermore, by integrating micro-electromechanical processes with electric circuits to produce much smaller actuators can meet the future trend of the optical storage technology because of their quasi-plane arrangement. This paper summarizes relative literatures and introduces working principles for the required performance of optical pickup head actuators. From conceptual design to prototype implementation, magnetic theories, such as equivalent magnetic circuit method, equivalent magnetic charge method, and equivalent current method are used to analyze the characteristics of the actuator. Finite element analysis software, ANSYS, is also applied to predict structural vibration. Finally, the dynamic characteristics of the actuator are tested by using a laser doppler vibrometer. In comparison with an existing optical pickup head, SPU3200, manufactured by Sankyo Seiki Mfg. Co., about one-third moving mass of the actuator is reduced. In addition, six and half times higher in stiffness, three and half times higher in open-loop bandwidth are achieved.
45
Dai, Chih-Long, and 戴志龍. "The Structural Analysis of CD-ROM Pickup Assembly." Thesis, 1996. http://ndltd.ncl.edu.tw/handle/12874788820023973036.
Full textAbstract:
碩士國立臺灣大學
機械工程學研究所
84
The focal length of the focusing lens also plays an important role:higher energy reflectivity may be obtained with shorter focal lengths, while stronger pulse compression effect may occur with longer focal lengths. The SBS reflectivity and threshold energy may vary with the distance between the focal lens and the SBS cell.
46
shen-Ghi, Lin, and 林炫志. "Developing a new Pickup truck through marketing research." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/69252400566514345592.
Full textAbstract:
碩士華梵大學
工業設計學系碩士班
96
With the technology development of automobile industry, there is a wider variety of car styles. Many models have been developed from the basic type of sedans according to the user’s needs. In addition to the individual user’s needs, the product style of cars is one of the most important requirements. In this study, the Pickup truck was chosen for the marketing research and new product design and development. The form features of specific Pickup samples were described and analyzed to construct the design specifications. The purpose of this study was listed below: (1) To explore the user’s needs of Pickup truck; (2) To collect the image data of Pickup trucks; (3) To build up the design specification of product form for Pickup trucks; (4) To construct evaluate a new Pickup truck based on user’s preference and the design speciation obtained from the statistical analysis. There are four stages of the experiment of preference and image evaluation of Pickup trucks. In the first stage, samples of pickup trucks and images were collected and selected. At second stage, a morphological analysis for pickup trucks was conducted. At third stage, a semantic differential experiment was performed. At last, a review test was conducted to verify the preference and image perceptions of the newly developed ideas of pickup trucks. With the average data of preference and image perceptions, a regression analysis was conducted to identify the target images for new pickup trucks. Through quantification type I analysis, the design specifications of pickup trucks in terms of preference and target images was built. Finally, two ideas for new pickup trucks were developed and evaluated for the final prototype.
47
Hsieh, Min-sheng, and 謝敏生. "Highly Efficient Optical Pickup Head for Blu-ray Disc." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/50724321566424895509.
Full textAbstract:
碩士國立中央大學
光電科學研究所碩士在職專班
95
The low efficiency of traditional pickup head is limited by the difference of vertical divergent angle and horizontal divergent angle. The vertical divergent angle is much larger than the horizontal one. To get the circular laser beam, the collimating lens is designed with the divergent angle which intensity is in the horizontal direction. Therefore there is a lot of energy wasted. This thesis uses the cylindrical afocal system and the prismatic system to expand the beam separately in the horizontal direction. The expander makes the beam size which intensity is in the horizontal direction as large as the beam size which intensity is in the vertical direction. Then the highly efficient collimating lens is designed with the divergent angle in the vertical direction. First, this thesis designs traditional Blu-ray Disc pickup head. It covers the design of its objective lens, the design of its collimating lens, tolerance analysis and the focusing error signal, and then simulates the total efficiency. This thesis introduces the concept of beam expanded in the horizontal direction to improve the total efficiency. This thesis designs the cylindrical expander and prismatic expander. It also covers the design of the collimating lens, tolerance analysis and the focusing error signal, and then simulates the total efficiency. At last summarize all of the new designs which are proposed by the thesis.
48
Cheng, Li-Kang, and 鄭力綱. "Study of In-Line Gratings for Optical Pickup Heads." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/10547752492678287085.
Full textAbstract:
碩士國立中興大學
機械工程學系所
101
This study investigated various types of in-line gratings on generating the differential push-pull (DPP) signal for the tracking detection of an optical pick head (OPH). The method of in-line DPP is different from that of the conventional DPP. The advantage is that it doesn’t need to consider the relation between the track pitch of each disk type and the corresponding angle of diffraction orders. With the study, we obtained the quality of the tracking error signals (TESs) for various types of in-line gratings, and discussed the in-line grating patterns that are applicable to the OPH applications. By using the numerical analysis software of Matlab, we first designed the phase profiles of the in-line gratings. The fast Fourier transform was then applied to simulate the intensity distributions of the zeroth, positive-first, and negative-first diffraction orders. Besides, we simulated the interference distributions of the push-pull signals for the in-line gratings. Furthermore, the TESs were calculated according to the track pitch of different disk types. Also, the comparisons between the TES quality and the shifting effect of the objective lens were performed for various types of in-line gratings. After the simulation, we found that the TESs of DVD-R and BD-R disks have the same tendency. A better TES could be obtained by reducing the width of the intermediate region of an in-line grating. Finally, the devices of all simulated in-line grating patterns were fabricated by using the photolithography and etching processes. Their optical diffraction efficiencies were verified for being consistent with the original designs. The dark and bright variations of the push-pull signal were also experimentally observed by setting up two OPH configurations.
49
Li, Yu-Lin, and 李育霖. "Nanometer Aperture Probe Array of Optical Pickup Head Design." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/46643151217492383399.
Full textAbstract:
碩士國立彰化師範大學
電機工程學系
97
In the optical storage technology, in order to get the higher density of storage, we must be narrow recording spot size for overcome diffraction limit. So savants propose near field theory to improve it. In near field theory, nanometer aperture probe and solid immersion lens (SIL) can overcome diffraction limit and narrow recording spot size. But power of light through nanometer aperture probe is very low. If we combine nanometer aperture and solid immersion lens, the power will increase. But the nanometer aperture probe and solid immersion lens size are different too much, the alignment is difficult, so we propose use cylindrical solid immersion lens scanning on the nanometer aperture probe, this method can improve misalignment. If we calculate total internal reflection of solid immersion lens produce evanescent wave distance, and design length of nanometer aperture probe, we can get better power for nanometer aperture probe so we optimize size and length of nanometer aperture probe. And then we add micro lens and micro cylindrical lens on the nanometer aperture probe, the power will increase.Our using type neural network analyzes the deviation angle of light source, with the lens structure of revision.
50
Lyu, Sin-Ru, and 呂欣茹. "Pickup-Delivery and Job Scheduling: A Computational Intelligence Approach." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/5mk682.
Full textAbstract:
碩士國立暨南國際大學
資訊管理學系
102
Logistic strategy is a prevalent issue in the supply chain management (SCM) research due to the large demand of on-line purchase, revealing the importance of task scheduling and vehicle routing. Based on the process of parallel machine scheduling, this research developed a two-phase vehicle-routing and task-scheduling model which fits many scenarios of manufacturing. In particular, the aim is to minimize the transportation cost and the makespan by considering the two phases simultaneously. This research also proposed a co-evolution framework combining a hyper-heuristic and an elite ant colony algorithm. The experimental result showed that the optimal solution cannot be obtained simply by concatenating the optimal solution for each separate phase, supporting our claim that the two-phase process is best dealt with by a co-evolution method which compromises between the goals of each phase.