87 resultados para Assortment


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"Preface and apology" on p. [3] contains information on Mrs. Fisher's life and names of benefactors in San Francisco and Oakland who assisted her in writing the book.

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Thesis (Ph.D.)--University of Washington, 2016-06

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Background Considerable evidence from twin and adoption studies indicates that genetic and shared environmental factors play a significant role in the initiation of smoking behavior. Although twin and adoption designs are powerful to detect genetic and environmental influences, they do not provide information on the processes of assortative mating and parent–offspring transmission and their contribution to the variability explained by genetic and/or environmental factors. Methods We examined the role of genetic and environmental factors for smoking initiation using an extended kinship design. This design allows the simultaneous testing of additive and non-additive genetic, shared and individual-specific environmental factors, as well as sex differences in the expression of genes and environment in the presence of assortative mating and combined genetic and cultural transmission. A dichotomous lifetime smoking measure was obtained from twins and relatives in the Virginia 30,000 sample. Results Results demonstrate that both genetic and environmental factors play a significant role in the liability to smoking initiation. Major influences on individual differences appeared to be additive genetic and unique environmental effects, with smaller contributions from assortative mating, shared sibling environment, twin environment, cultural transmission and resulting genotype–environment covariance. The finding of negative cultural transmission without dominance led us to investigate more closely two possible mechanisms for the lower parent–offspring correlations compared to the sibling and DZ twin correlations in subsets of the data: (i) age × gene interaction, and (ii) social homogamy. Neither mechanism provided a significantly better explanation of the data, although age regression was significant. Conclusions This study showed significant heritability, partly due to assortment, and significant effects of primarily non-parental shared environment on smoking initiation.

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Regionális klímaváltozási forgatókönyvek szerint hazánk éghajlata az elkövetkező 90 évben a mainál jóval melegebb, a nyári évszakban csapadékszegényebb, összességében pedig szárazabb lesz. Kutatásunk célja volt felmérni szárazságtűrésük szerint a legjelentősebb faiskolák katalógusában fellelhető fa- és cserjefajokat (a gyűjtésben nem szerepelnek a faj alatti taxonok). A vizsgálatainkban szereplő öt faiskola növénykínálatát a tudományos nevek ellenőrzése után összesítettük, majd ezt követően az egyes fajokat vízigény szerinti kategóriákba soroltuk. A tényleges statisztikai értékelésbe – a 451 összegyűjtött faj tudományos neveinek ellenőrzése után – 420 fajt vontunk be, melyek 20%-a vízigényes, 53%-a közepesen vízigényes és 27%-a szárazságtűrő. Várakozásainkkal ellentétben a vízigényes fajok részaránya kevésnek mondható, ugyanakkor a szárazságtűrő fajok magasabb aránya kívánatos lenne. Ezért, a gyakorlati alkalmazást elősegítve, kiemeltünk olyan nemzetségeket, melyek kereskedelmi forgalmazását meg kellene kezdeni vagy fokozni, mint pl a Cupressus, Eucommia, Halimodendron, Paliurus, Pyrus, Rhus, Yucca Zanthoxylum, Zelkova, illetve olyanokat, melyek telepítését a jövőben nem, vagy csak kellő körültekintéssel javasoljuk, mint például a Clematis, Hydrangea, Liquidambar, Magnolia, Rhododendron nemzetségek. _____ According to regional climate change scenarios, the climate in Hungary will be warmer. Less precipitation is predicted in the summer seasons so, on the whole, it will be drier over the next 90 years. Our research attempted to survey the ornamental plant species in the most important nurseries in Hungary, in terms of their drought tolerance. The intraspecifi c taxa are not included. The plant assortment of the fi ve nurseries was merged after researching their scientifi c names. We then categorized species to 3 groups of drought tolerance. Out of 451 species, 420 of them were used in the statistical research. 20% of them were water demanding, 53% were medium drought tolerant and 27% were drought tolerant. In contrast to our initial expectation, the proportion of water demanding species was not too high. Nevertheless, the proportion of drought tolerant species should have been greater. We classifi ed the genera to assist in practical application. The trade of some of these species, such as Cupressus, Eucommia, Halimodendron, Paliurus, Pyrus, Rhus, Yucca, Zanthoxylum, Zelkova should be initiated or increased in the future. Other species, especially Clematis, Hydrangea, Liquidambar, Magnolia, Rhododendron are not recommended due to either their drought intolerance or their high maintenance requirement.

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The climate modeling, which has adequate spatial and temporal resolution, shows that the future climate of the Carpathian Basin will be much more arid and hot than nowadays. The currently used and taught assortment of the ligneous ornamental plants should be urgently revised. It is aimed in my research to collect the species which will probably be introduced in the future. They can be gathered from the Hungarian botanical gardens and research centers and from the spatially analogous territories. The collected taxa should be examined with GIS software if they will really suffer our future climate.

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The inherent analogue nature of medical ultrasound signals in conjunction with the abundant merits provided by digital image acquisition, together with the increasing use of relatively simple front-end circuitries, have created considerable demand for single-bit  beamformers in digital ultrasound imaging systems. Furthermore, the increasing need to design lightweight ultrasound systems with low power consumption and low noise, provide ample justification for development and innovation in the use of single-bit  beamformers in ultrasound imaging systems. The overall aim of this research program is to investigate, establish, develop and confirm through a combination of theoretical analysis and detailed simulations, that utilize raw phantom data sets, suitable techniques for the design of simple-to-implement hardware efficient  digital ultrasound beamformers to address the requirements for 3D scanners with large channel counts, as well as portable and lightweight ultrasound scanners for point-of-care applications and intravascular imaging systems. In addition, the stability boundaries of higher-order High-Pass (HP) and Band-Pass (BP) Σ−Δ modulators for single- and dual- sinusoidal inputs are determined using quasi-linear modeling together with the describing-function method, to more accurately model the  modulator quantizer. The theoretical results are shown to be in good agreement with the simulation results for a variety of input amplitudes, bandwidths, and modulator orders. The proposed mathematical models of the quantizer will immensely help speed up the design of higher order HP and BP Σ−Δ modulators to be applicable for digital ultrasound beamformers. Finally, a user friendly design and performance evaluation tool for LP, BP and HP  modulators is developed. This toolbox, which uses various design methodologies and covers an assortment of  modulators topologies, is intended to accelerate the design process and evaluation of  modulators. This design tool is further developed to enable the design, analysis and evaluation of  beamformer structures including the noise analyses of the final B-scan images. Thus, this tool will allow researchers and practitioners to design and verify different reconstruction filters and analyze the results directly on the B-scan ultrasound images thereby saving considerable time and effort.

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In this thesis, novel analog-to-digital and digital-to-analog generalized time-interleaved variable bandpass sigma-delta modulators are designed, analysed, evaluated and implemented that are suitable for high performance data conversion for a broad-spectrum of applications. These generalized time-interleaved variable bandpass sigma-delta modulators can perform noise-shaping for any centre frequency from DC to Nyquist. The proposed topologies are well-suited for Butterworth, Chebyshev, inverse-Chebyshev and elliptical filters, where designers have the flexibility of specifying the centre frequency, bandwidth as well as the passband and stopband attenuation parameters. The application of the time-interleaving approach, in combination with these bandpass loop-filters, not only overcomes the limitations that are associated with conventional and mid-band resonator-based bandpass sigma-delta modulators, but also offers an elegant means to increase the conversion bandwidth, thereby relaxing the need to use faster or higher-order sigma-delta modulators. A step-by-step design technique has been developed for the design of time-interleaved variable bandpass sigma-delta modulators. Using this technique, an assortment of lower- and higher-order single- and multi-path generalized A/D variable bandpass sigma-delta modulators were designed, evaluated and compared in terms of their signal-to-noise ratios, hardware complexity, stability, tonality and sensitivity for ideal and non-ideal topologies. Extensive behavioural-level simulations verified that one of the proposed topologies not only used fewer coefficients but also exhibited greater robustness to non-idealties. Furthermore, second-, fourth- and sixth-order single- and multi-path digital variable bandpass digital sigma-delta modulators are designed using this technique. The mathematical modelling and evaluation of tones caused by the finite wordlengths of these digital multi-path sigmadelta modulators, when excited by sinusoidal input signals, are also derived from first principles and verified using simulation and experimental results. The fourth-order digital variable-band sigma-delta modulator topologies are implemented in VHDL and synthesized on Xilinx® SpartanTM-3 Development Kit using fixed-point arithmetic. Circuit outputs were taken via RS232 connection provided on the FPGA board and evaluated using MATLAB routines developed by the author. These routines included the decimation process as well. The experiments undertaken by the author further validated the design methodology presented in the work. In addition, a novel tunable and reconfigurable second-order variable bandpass sigma-delta modulator has been designed and evaluated at the behavioural-level. This topology offers a flexible set of choices for designers and can operate either in single- or dual-mode enabling multi-band implementations on a single digital variable bandpass sigma-delta modulator. This work is also supported by a novel user-friendly design and evaluation tool that has been developed in MATLAB/Simulink that can speed-up the design, evaluation and comparison of analog and digital single-stage and time-interleaved variable bandpass sigma-delta modulators. This tool enables the user to specify the conversion type, topology, loop-filter type, path number and oversampling ratio.

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Purpose of this paper:
Recent literature indicates that around one third of perishable products finish as waste (Mena et al., 2014): 60% of this waste can be classified as avoidable (EC, 2010) suggesting logistics and operational inefficiencies along the supply chain. In developed countries perishable products are predominantly wasted in wholesale and retail (Gustavsson et al., 2011) due to customer demand uncertainty the errors and delays in the supply chain (Fernie and Sparks, 2014). While research on logistics of large retail supply chains is well documented, research on retail small and medium enterprises’ (SMEs) capabilities to prevent and manage waste of perishable products is in its infancy (c.f. Ellegaard, 2008) and needs further exploration. In our study, we investigate the retail logistics practice of small food retailers, the factors that contribute to perishable products waste and the barriers and opportunities of SMEs in retail logistics to preserve product quality and participate in reverse logistics flows.

Design/methodology/approach:
As research on waste of perishable products for SMEs is scattered, we focus on identifying key variables that contribute to the creation of avoidable waste. Secondly we identify patterns of waste creation at the retail level and its possibilities for value added recovery. We use explorative case studies (Eisenhardt, 1989) and compare four SMEs and one large retailer that operate in a developed market. To get insights into specificities of SMEs that affect retail logistics practice, we select two types of food retailers: specialised (e.g. greengrocers and bakers) and general (e.g. convenience store that sells perishable products as a part of the assortment)

Findings:
Our preliminary findings indicate that there is a difference between large retailers and SME retailers in factors that contribute to the waste creation, as well as opportunities for value added recovery of products. While more factors appear to affect waste creation and management at large retailers, a small number of specific factors appears to affect SMEs. Similarly, large retailers utilise a range of practices to reduce risks of product perishability and short shelf life, manage demand, and manage reverse logistics practices. Retail SMEs on the other hand have limited options to address waste creation and value added recovery. However, our findings show that specialist SMEs could successfully minimize waste and even create possibilities for value added recovery of perishable products. Data indicates that business orientation of the SME, the buyersupplier relationship, and an extent of adoption of lean principles in retail coupled with SME resources, product specific regulations and support from local authorities for waste management or partnerships with other organizations determine extent of successful preservation of a product quality and value added recovery.

Value:
Our contribution to the SCM academic literature is threefold: first, we identify major factors that contribute to the generation waste of perishable products in retail environment; second, we identify possibilities for value added recovery for perishable products and third, we present opportunities and challenges for SME retailers to manage or participate in activities of value added recovery. Our findings contribute to theory by filling a gap in the literature that considers product quality preservation and value added recovery in the context of retail logistics and SMEs.

Research limitations/implications:
Our findings are limited to insights from five case studies of retail companies that operate within a developed market. To improve on generalisability, we intend to increase the number of cases and include data obtained from the suppliers and organizations involved in reverse logistics flows (e.g. local authorities, charities, etc.).

Practical implications:
With this paper, we contribute to the improvement of retail logistics and operations in SMEs which constitute over 99% of business activities in UK (Rhodes, 2015). Our findings will help retail managers and owners to better understand the possibilities for value added recovery, investigate a range of logistics and retail strategies suitable for the specificities of SME environment and, ultimately, improve their profitability and sustainability.

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Bakgrund Dagligvaruhandel på internet växer och efterfrågas från fler kunder än någonsin tidigare. De större aktörerna märker att efterfrågan finns och inser att de behöver utöka sina försäljningskanaler, samtidigt som de mindre företagen som varit med och bidragit till denna efterfrågan behöver arbeta för att hålla sina kunder lojala och inte förlora marknadsandelar när marknadssituationen förändras av de stora aktörerna. Den förändrade konkurrenssituationen innebär att företag behöver lägga större fokus på kunden genom strategi och framförallt uppbyggnaden av lojalitet. Syfte Syftet är att få en ökad kunskap om hur ett företag som var tidigt ute på en marknad håller sina kunder lojala i samband med att konkurrenssituationen förändras. Metod För att besvara syftet har en kvalitativ fallstudie om företaget MatHem gjorts, för att slutligen kunna dra en generaliserad slutsats. Där insamling av primärdata och sekundärdata har analyserats för att slutligen nå en slutsats. Slutsats Det undersökta företaget håller sina kunder lojala genom att ha en hög generell kvalitet. Vilket betyder att de har hög kvalitet på produkterna, väl fungerande kundservice, överträffar kundens förväntningar och ett brett sortiment. När konkurrenssituationen förändras har företaget inga speciella strategier för att hålla sina kunder lojala, eftersom att företaget inte ser de andra aktörerna som konkurrenter. Företaget är den dyraste aktören på marknaden, men differentierar sig med ekologiska produkter för att erhålla lojala kunder.

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Placer miners in Alaska’s interior were part of the last great gold rush in North America. As word of gold in the Fairbanks Mining District traveled down the Yukon River, a wave of miners from the Klondike placer fields in Dawson, along with a assortment of speculators and inexperienced green horns from the Lower 48 converged on the confluence of the Tanana and Chena rivers hoping to strike it rich. The steamers coming from Dawson were integral; they carried miners with experience working the frozen subarctic placer deposits of the Klondike. These miners encountered new environmental challenges that required the development of new technologies and mining methods to efficiently harvest gold. These methods and machines were brought into Fairbanks and further perfected to account for the local conditions. This thesis describes the local mining technologies and methods employed in the Fairbanks district and the landscape patterns created during the placer mining boom years of 1903-1909, decline years of 1910-1923 and recovery of 1923-1930.

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Activated carbon (AC) has proved to be an effective adsorbent for the removal of an assortment of organic and inorganic pollutants from aqueous or gaseous media. However, the pursuit for more effective and cheaper AC is still very active and a diversity of textural and chemical treatments are described as a way to expand their applications. It is well known that the surface area and surface chemistry of AC strongly affect their adsorption capacity [1-3]. In particular, an increase in the nitrogen content has been related to an increase of the basic character and also to the development of the porous structure. In most published work this was achieved through an AC post treatment, including either a reaction with nitrogen containing reagents, such as ammonia, nitric acid, or a diversity of amines. However, the AC prepared directly from a nitrogen rich precursor through a physical or chemical activation is referred to as presenting the best characteristics, namely high nitrogen content, high basic character, low nitrogen leaching and also a good thermal stability [4]. To improve the AC adsorption capacities for acidic pesticide removal from the aqueous phase, we intend to improve the porous structure and introduce nitrogenated groups directly into the AC matrix, using different co-adjuvant activating agents as a nitrogen source, by chemical activation, with potassium hydroxide, of cork or poly(ethyleneterephthalate) (PET) precursors.

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This thesis provides an ex-post evaluation of the effects of regulatory and competition policy enforcement interventions on non-price dimensions of competition. Chapter 1 examines the effects of a merger between two large Dutch supermarket chains on the variety and composition of product assortment. Chapter 2 and Chapter 3 investigate, both theoretically and empirically, the effects of access regulation in fixed telecoms markets on incentives to invest in superior infrastructure technologies. Non-price effects, together with price effects, are crucial to shed light on the extent of competition in a market and assess the effectiveness of regulatory and competition authorities' interventions. When evaluating non-price effects, however, it is harder to draw conclusions on the overall impact on consumers' welfare.