The preschool years are an important time in the development of understanding the property of weight. This experiment investigates whether social learning, specifically imitation, will promote preschoolers’ use of this property. Children were randomly assigned to one of three groups. Those in the experimental group saw an adult sort four objects based on their weights. Children were then presented with the objects. Whether children sorted these objects based on their weights was scored, as was their sorting of a novel set of objects (to assess generalization) and their imitation of the hefting gestures used by the adult. Comparisons to control groups indicated that 4-year-olds, but not 3-year-olds, benefitted from the modeling and sorted by weight. These results suggest that social learning is an effective way to promote children’s use of this invisible property.

<p>Urban problems have several features that make them inherently dynamic. Large transaction costs all but guarantee that homeowners will do their best to consider how a neighborhood might change before buying a house. Similarly, stores face large sunk costs when opening, and want to be sure that their investment will pay off in the long run. In line with those concerns, different areas of Economics have made recent advances in modeling those questions within a dynamic framework. This dissertation contributes to those efforts.</p><p>Chapter 2 discusses how to model an agent’s location decision when the agent must learn about an exogenous amenity that may be changing over time. The model is applied to estimating the marginal willingness to pay to avoid crime, in which agents are learning about the crime rate in a neighborhood, and the crime rate can change in predictable (Markovian) ways.</p><p>Chapters 3 and 4 concentrate on location decision problems when there are externalities between decision makers. Chapter 3 focuses on the decision of business owners to open a store, when its demand is a function of other nearby stores, either through competition, or through spillovers on foot traffic. It uses a dynamic model in continuous time to model agents’ decisions. A particular challenge is isolating the contribution of spillovers from the contribution of other unobserved neighborhood attributes that could also lead to agglomeration. A key contribution of this chapter is showing how we can use information on storefront ownership to help separately identify spillovers.</p><p>Finally, chapter 4 focuses on a class of models in which families prefer to live</p><p>close to similar neighbors. This chapter provides the first simulation of such a model in which agents are forward looking, and shows that this leads to more segregation than it would have been observed with myopic agents, which is the standard in this literature. The chapter also discusses several extensions of the model that can be used to investigate relevant questions such as the arrival of a large contingent high skilled tech workers in San Francisco, the immigration of hispanic families to several southern American cities, large changes in local amenities, such as the construction of magnet schools or metro stations, and the flight of wealthy residents from cities in the Rust belt, such as Detroit.</p> / Dissertation

Indien är ett land som växer ekonomiskt samtidigt som problem med hur avfall ska tas omhand fortfarande är i utvecklingsfasen. Studiens fokus ligger på hur avfallshanteringen sköts i staden Bangalore. Utifrån ett svenskt perspektiv på avfallshantering med insamling och behandling har Bangalore undersökts och brister lokaliserats. Förbättringsförslag presenteras utifrån de brister som framkommit och ett fokus har lagts på om svenska avfallslösningar skulle kunna implementeras i Bangalore. Svensk avfallshantering utgör en bra grund för ett funktionellt avfallshanteringssystem och har därför använts som referens vid jämförelser och förbättringsförslag. I Sverige används källsortering vid sortering av avfall för att få en högre grad av återvinningsbarhet. De behandlingssteg som finns ger energi på olika sätt och ytterst lite avfall läggs på deponier. Ett ständigt arbete utförs utifrån avfallstrappans steg. I Bangalore är situationen omvänd och det avfall som lyckas samlas in hamnar till största delen på deponier eller inofficiella dumpningsplatser runt om i staden. I Sverige sköts avfallshanteringen av den formella sektorn medan den i Bangalore till stor del utförs av en informell sektor där privata personer samlar in skräp. En litteraturstudie har gett insikt i vilka problem utvecklingsländer kan ha gällande avfallshantering och även vilka faktorer som spelar in vid verkställandet av ett fungerande system. I projektet gjordes en observationsstudie på plats i Bangalore under två veckors tid. Utifrån observationsstudien kunde mycket av tidigare information kring hur avfallshanteringen går till granskas mer kritiskt och ett mer verklighetstroget resultat framföras. Det saknas ett fungerande system som är heltäckande för hela Bangalore, vilket gör att mycket avfall hamnar direkt på gator eller på övergivna tomter. Detta i sin tur ger upphov till dålig lukt för invånarna och en ohygienisk miljö. De insamlingssystem som finns att tillgå för allmänheten var i övergripande fall otillräckliga. Tre olika faktorer identifierades som hindrar att avfallshanteringen ska kunna fungera. Dessa var politik, den formella och informella sektorn, samt insamlingssystem av avfall. Ett stort hinder inom Bangalore är det bristande politiska intresset att få till en fungerande avfallshantering. Inga stora aktioner eller krafttag tas mot de växande mängder avfall som produceras. Inte heller sker en bra integration mellan de formella avfallsinsamlarna som utgörs av avfallstransporter och avfallsinsamlare versusinofficiella avfallsinsamlare. Då Bangalore saknar ett formellt insamlingssystem ges inte rätta förutsättningar för befolkningen att kunna gå någonstans med sitt avfall. Detta leder till en ökad okunskap om hur avfall bör sorteras för att kunna behandlas på ett lämpligt sätt där föredragsvis energi kan utvinnas. Ett tydligare insamlingssystem behövs om Bangalore ska kunna nå en hållbar utveckling och bromsa de eskalerande miljöproblem som de ställs inför. Någon form av behandling av avfall krävs för att minska mängden avfall som hamnar direkt på deponering. Genom att minska trycket på deponierna finns en potential för att få en hållbar stad. / India is a country that is growing economically while the problems with the waste andit´s treatment are still in the development phase. The study focuses on how the waste ishandled in the city of Bangalore. From a Swedish point of view the waste collection andtreatment have been investigated Bangalore and shortcomings identified. Suggestionsfor improvements are presented from the lack of the waste management and the focushas been on how Swedish solutions could be implemented in Bangalore. In Sweden the sorting of waste at a household level is managed from different fractionsin containers and therefore the waste has a higher degree of recyclability. Theprocessing steps that are providing energy are sufficient leading to very little wastebeing added to landfills. A constant work is done based on the waste hierarchy. InBangalore, the situation is the reverse and the waste collected mostly ends up inlandfills or unofficial dumping sites around the city. In Sweden, waste is handled by theformal sector, while Bangalore is largely dependent on an informal sector whereindividuals collect waste. A literature study has provided insight into the difficulties developing countries mayhave to face regarding waste management and the factors that come into play in theexecution of a functioning system. Within the project, an observational study was madein Bangalore for two weeks. Based on the observational study a lot of previousinformation on how waste is handled could be examined more critically and morerealistic conclusions drawn. The lack of a functioning system for waste collectionthroughout Bangalore results in a lot of waste ending up directly on the streets or onabandoned plots. This in turn gives rise to odors for residents and an unhygienicenvironment. The collection available to the public was in most cases insufficient. Three factors were identified that prevent the waste management from functioning.These were politics, the formal and informal sector, as well as the practical collectionof waste. A major obstacle in Bangalore is the lack of political interest of functioningwaste management. No major action is taken against the growing amounts of wasteproduced. A good integration between the formal waste collectors consisting of thetransport of waste and waste collectors versus informal waste collectors is missing.Bangalore also lacks formal collection systems and the people are not given the rightconditions to be able to go anywhere to get rid of their waste. This leads to increasedignorance about how waste should be sorted for processing appropriately and whereenergy can be recovered. A clearer collection is needed if Bangalore is to achieve sustainable development and tocurb the escalating environmental problems they face. Some form of waste treatment isneeded to reduce the pressure on the city landfill. By doing this there is a change for thecity to be sustainable and green.

<p>The thesis covered the creation and testing of a low cost and modular sorting system of pegs used in products by Lafayette Instruments. The system is designed to check peg dimensions through use of computer vision while sorting out nonconforming parts and counting ones that are conforming. Conforming parts are separated into bins of predetermined quantities so that they do not need manual counting. The developed system will save engineers and technicians at Lafayette instruments many man hours from manually sorting and counting the roughly 160,000 pegs a year. The system will be able to sort and count at a speed comparable to a human operator while achieving an overall average accuracy of 95% or higher.</p>

Qian Zhengfeng. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 127-129). / Abstracts in English and Chinese. / Chapter Chapter 1 --- Groundwork --- p.1 / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Exchange Patterns --- p.5 / Chapter 1.3 --- Multistage Networks --- p.9 / Chapter 1.3.1 --- Multistage Networks --- p.9 / Chapter 1.3.2 --- Banyan-type Networks --- p.11 / Chapter 1.4 --- Networks of Sorting Cells --- p.15 / Chapter 1.5 --- Symbolic Representation and Matrix Representation --- p.19 / Chapter 1.5.1 --- Symbolic Representation of a Multistage Interconnection Network --- p.19 / Chapter 1.5.2 --- Symbolic Representation of a Network of Sorting Cells --- p.21 / Chapter 1.5.3 --- Matrix Representation of a Network of Sorting Cells --- p.22 / Chapter 1.6 --- Summary --- p.24 / Chapter Chapter 2 --- Construction of Generalized Bitonic Sorters by Merging Rotated Monotonic Sequences --- p.25 / Chapter 2.1 --- Merging Networks --- p.25 / Chapter 2.1.1 --- Recursive 2-stage Construction --- p.26 / Chapter 2.1.2 --- UC/CU Non-blocking Switches --- p.35 / Chapter 2.1.3 --- Circular Sorters and Merging Networks --- p.41 / Chapter 2.2 --- Construction of Generalized Bitonic Sorters --- p.48 / Chapter 2.2.1 --- Bitonic Ar-sorters and Bitonic Dr-sorters --- p.48 / Chapter 2.2.2 --- Algorithms for Construction of Generalized Bitonic Sorters by Merging Rotated Monotonic Sequences --- p.51 / Chapter 2.3 --- Summary --- p.73 / Chapter Chapter 3 --- Construction of Generalized Bitonic Sorters by Cross-k Cell Rearrangement --- p.74 / Chapter 3.1 --- Cross-k Cell Rearrangement on a Multistage Network --- p.74 / Chapter 3.1.1 --- Intra-stage Cell Rearrangement --- p.74 / Chapter 3.1.2 --- Equivalence of Networks --- p.77 / Chapter 3.1.3 --- Cross-k Cell Rearrangement --- p.80 / Chapter 3.2 --- Construction of Generalized Bitonic Sorters --- p.85 / Chapter 3.3 --- Summary --- p.99 / Chapter Chapter 4 --- Redundancy of the Bitonic Network --- p.100 / Chapter 4.1 --- Counting of Identified Generalized Bitonic Sorters --- p.100 / Chapter 4.2 --- Redundancy of the Bitonic Network --- p.110 / Epilogue --- p.112 / Appendix C Program for Exhaustive Search of 8×8 Generalized Bitonic Sorters --- p.113 / References --- p.127

The focus of this thesis is on systems that employ both flash and magnetic disks as storage media. Considering the widely disparate I/O costs of flash disks currently on the market, our approach is a cost-aware one: we explore techniques that exploit the I/O costs of the underlying storage devices to improve I/O performance. We also study the asymmetric I/O properties of magnetic and flash disks and propose algorithms that take advantage of this asymmetry. Our work is geared towards database systems; however, most of the ideas presented in this thesis can be generalised to any data-intensive application. For the case of low-end, inexpensive flash devices with large capacities, we propose using them at the same level of the memory hierarchy as magnetic disks. In such setups, we study the problem of data placement, that is, on which type of storage medium each data page should be stored. We present a family of online algorithms that can be used to dynamically decide the optimal placement of each page. Our algorithms adapt to changing workloads for maximum I/O efficiency. We found that substantial performance benefits can be gained with such a design, especially for queries touching large sets of pages with read-intensive workloads. Moving one level higher in the storage hierarchy, we study the problem of buffer allocation in databases that store data across multiple storage devices. We present our novel approach to per-device memory allocation, under which both the I/O costs of the storage devices and the cache behaviour of the data stored on each medium determine the size of the main memory buffers that will be allocated to each device. Towards informed decisions, we found that the ability to predict the cache behaviour of devices under various cache sizes is of paramount importance. In light of this, we study the problem of efficiently tracking the hit ratio curve for each device and introduce a lowoverhead technique that provides high accuracy. The price and performance characteristics of high-end flash disks make them perfectly suitable for use as caches between the main memory and the magnetic disk(s) of a storage system. In this context, we primarily focus on the problem of deciding which data should be placed in the flash cache of a system: how the data flows from one level of the memory hierarchy to the others is crucial for the performance of such a system. Considering such decisions, we found that the I/O costs of the flash cache play a major role. We also study several implementation issues such as the optimal size of flash pages and the properties of the page directory of a flash cache. Finally, we explore sorting in external memory using external merge-sort, as the latter employs access patterns that can take full advantage of the I/O characteristics of flash memory. We study the problem of sorting hierarchical data, as such is necessary for a wide variety of applications including archiving scientific data and dealing with large XML datasets. The proposed algorithm efficiently exploits the hierarchical structure in order to minimize the number of disk accesses and optimise the utilization of available memory. Our proposals are not specific to sorting over flash memory: the presented techniques are highly efficient over magnetic disks as well.

Non-contact manipulation technologies present a useful and powerful means of handling particles or cells. Such techniques are of interest in regenerative medicine applications, and in particular the scalability of these techniques is an area of active research. Optical trapping is a precise and dextrous method of manipulating particles with the forces exerted by a laser beam, while acoustic trapping is a scalable technique capable of exerting a force on particles through standing wave resonance. These complimentary modalities can be utilised in a hybrid system to give a resultant technique that borrows from the strengths of each individual method. In this thesis, methods of force balancing, using optics and acoustics, are explored, both independently and in combination with each other. A technique for 3D acoustic trapping in glass capillaries is shown, utilising the two pairs of opposing channel walls and the air-water interfaces of two air bubbles as acoustic reflectors. Standing waves set up between these surfaces show discrete acoustic trapping sites for varying lengths of fluid cavity. A method of optical radiation force balancing is observed in a 3D potential energy landscape, using similar principles as seen in particle trapping with counter-propagating beams. Tuning of the radiation force balance in this system allows particles to, instead of being pinned to the surface by the radiation force from the optical pattern, become localised at discrete planes of trapping sites throughout the fluid volume. A hybrid force balance separation method using the optical and acoustic forces is devised using a single laser beam as the primary deflection mechanism with acoustic trapping providing both localisation and a force balance with the optics. Separation of different sized particles is observed, with larger scale optical deflection mechanisms and their resultant thermal effects demonstrated.

A method to parallelize external sorts on a shared memory multiprocessing system is presented in this thesis. The main goal of the thesis is to develop a sorting package that is scale able and efficient. No prior knowledge of the nature, source or size of the data is assumed for this work. A dynamic load-balancing architecture is used with no static allocation of tasks to processes. The package consists of an interface and a kernel. The interface provides the sort with the following - the sort input, output and temporary work spaces as abstract data types (ADTs), memory available, number of processes available, compare routine to compare records, etc. Only the interface needs to be changed to suit different environments. The kernel implements the parallel sort algorithm. The traditional sort merge technique is used for the external sort as opposed to a distributive sorting technique. Memory-sized runs are first generated and later merged. Parallel binary merges is the technique used for both the run generation and the merge phase. A forecasting table is used to read ahead in the merge phase.

PhD / The aim of this thesis was to investigate the possibility of integrating frozen-thawed boar semen into reproductive technologies and into commercial production of pigs in Australia. This was to be achieved by establishing a semen freezing and AI regime that was of a standard acceptable to industry, and integrating the resultant frozen-thawed sperm into other reproductive technologies, such as flow cytometric sperm sorting and IVF. Initially, a protocol for freezing and thawing boar semen was established, based on the method described by Westendorf et al. (1975) and attempts were made to modify this protocol to improve the post-thaw sperm quality, as determined by in vitro assessment of motility, acrosome integrity and longevity. First, the egg yolk used in the freezing extenders was investigated, and the chicken yolk was replaced with either duck or quail yolk. It was shown that there was no benefit in substituting yolk from duck or quail for the chicken yolk traditionally used in freezing extender. Second, the effect of seminal plasma addition to the freezing extender, or seminal plasma addition to resuspension medium post-thaw was tested. Incorporating whole seminal plasma into the freezing extender at levels above 50% was found to be detrimental to post-thaw sperm quality. Reducing levels to 20% of the final volume improved acrosome integrity, but adversely affected motility of sperm. However, adding 20% seminal plasma to the resuspension medium used after thawing of boar semen had no significant influence on sperm quality compared with resuspension in medium without seminal plasma. The antioxidant catalase, and the iron chelator desferal added to the freezing extender, did not improve post-thaw sperm quality, nor was any benefit seen with addition of these substrates to the resuspension medium post-thaw. However, the bioactive phospholipid PAF and its regulating enzyme PAF:AH appeared to enhance post-thaw motility and acrosome integrity of sperm, respectively, when added to the semen pre-freezing. Unfortunately, due to the restrictions imposed on rPAF:AH as a research drug, it was not possible to test the in vivo effects at this time. After the in vitro experiments were completed, the in vivo fertility of frozen-thawed sperm was tested using the optimal freezing protocol and a novel technology, enabling non-surgical deep intrauterine insemination of sows. The aim was to establish the lowest possible dose of frozen-thawed sperm that could be used, without compromising fertility. Successful pregnancies were achieved with doses as low as 62.5 x 106 frozen-thawed sperm but the farrowing rates were too low to be practicable on a commercial scale. This is the first report of litters born after insemination of such a low dose of frozen-thawed sperm and using the novel DIU insemination technique. However, it was concluded that a double dose of 250 x 106 frozen-thawed sperm was the minimum dose required for maintaining acceptable fertility. Reduction in sperm numbers to such an extent made it possible to consider non-surgical insemination of sex-sorted, frozen-thawed semen. Previously, pregnancies had been achieved only after surgical insemination of sex-sorted boar sperm, or with DIU insemination of unfrozen sperm, immediately after sex-sorting. The low numbers of sex-sorted sperm available restricted the inseminate dose used here to 50 x106 motile sperm. A litter of 5 piglets was born after a low-dose, DIU insemination of sex-sorted, frozen-thawed sperm. This is the first report of piglets born after insemination with sex-sorted frozen-thawed sperm and non-surgical insemination. The low farrowing rate achieved in this experiment prompted the investigation of integrating sex-sorted, frozen-thawed boar sperm into IVF. Morulae were produced after IVF with sex-sorted, frozen-thawed sperm and successfully transferred using non-surgical techniques. This is the first report of pregnancy achieved with non-surgical transfer of embryos produced after IVF and IVC of IVM oocytes with sex-sorted, frozen-thawed boar sperm. Unfortunately, the pregnancy did not hold, and the embryos were lost prior to Day 32, but PCR of non-transferred embryos confirmed successful pre-selection of sex. Overall, this thesis demonstrated that it is still not economically feasible to incorporate frozen-thawed boar semen into the commercial production of pigs although it has considerable application in breeding programmes. However, the development of novel techniques enabling reduction in sperm dose, and for non-surgical transfer of embryos into recipient sows and incorporation of frozen-thawed semen into these technologies means that progress is being made with the integration of reproductive technologies and frozen-thawed semen into the pig industry.

Weathered waterborne treated wood is believed to behave differently than new wood during service regarding the loss of its metallic-based preservatives. Also, weathered preserved wood should be separated from the unpreserved wood upon recycle. The first objective of this dissertation was to evaluate losses from weathered CCA-treated wood samples at different retention levels under normal field conditions and to compare leaching to new ACQ (as alternative to CCA). Results showed that arsenic leached at a higher rate than chromium and copper in all CCA treated wood samples, while copper leached the highest from the ACQ sample. Overall results suggest that the leaching rate of metals on a percent basis from in-service pressure treated wood may increase as the wood weathers; however due to lower retention levels of the metals in the wood as it ages the yearly mass of metals lost would be at similar or at lower quantities in comparison to new treated wood. The second objective was to evaluate the use of automated X-ray fluorescence (XRF) systems for identifying and removing As-based and Cu-based treated wood within the recovered wood waste stream. A full-scale online automated XRF-detection, conveyance and diversion system was used for experimentation. At the different applied feeding rates and belt speeds, online sorting efficiencies of waste wood by XRF technology were high (>70% for both treated wood and untreated wood). The incorrectly diverted pieces of wood were attributed to deficiencies in the wood conveyance systems and not to deficiencies in the XRF-based detection. Online sorting was shown to sort wood which would meet the residential soil cleanup target levels in Florida when an infeed is composed of 5% of treated wood pieces. Comparisons with other sorting methods show that XRF technology can potentially fulfill the need for cost-effective processing at large wood recycling facilities (> 30 tons per day). Management of weathered CCA-preserved wood, due to its continuity of leaching metals and the need to remove it upon the recycle of wood, will likely continue until complete banning and removal from the environment, a process that may extend up to the next century.