Дисертації: "Endo selective"

1

Morten, Christopher J. (Christopher John). "Endo-selective epoxide-opening cascades in water." Thesis, Massachusetts Institute of Technology, 2011. http://hdl.handle.net/1721.1/65271.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2011.
Vita. Cataloged from PDF version of thesis.
Includes bibliographical references.
Chapter I. Introduction to the Ladder Polyethers. We introduce the bioactivity of the ladder polyether natural products and provide an overview of the puzzle that is their biogenesis. Cascades of endo-selective epoxide opening inspired by the biosynthetic proposal and promoted by simple neutral water can provide efficient access to these compounds. Chapter II. Water-Promoted Epoxide Opening Accommodates Methyl Substitution. ... Methyl (Me) substitution poses a challenge to the achievement of endo-selective epoxide-opening cascades, as these groups can direct the regioselectivity of epoxide opening. Water as reaction solvent and promoter overcomes such directing effects and enables the incorporation of proximally Me-substituted epoxides into endo-selective cascades. However, Me-substituted epoxides do reduce the overall efficiency of cascades. Chapter III. Kinetics of an Epoxide-Opening Cascade Promoted by Neutral Water. Evidence for a Stepwise Mechanism. ... Detailed investigation of the kinetics of an endo-selective epoxide-opening cascade in water reveals a stepwise mechanism, not a concerted one. While the first step proceeds with poor rate and selectivity, the second cyclization, which is templated by a fused THP diad, proceeds with excellent endo selectivity. Chapter IV. Preliminary Investigation of a Dioxane Template for Endo-Selective Epoxide-Opening Cyclization. ... Use of a 1,3-dioxane as template ring, a methylene acetal engenders endoselective epoxide opening under both acidic and basic conditions. Cyclization in neutral water proceeds with superb endo selectivity. Chapter V. Progress Toward the Synthesis of Gambierol via Endo-Selective Epoxide-Opening Cascades Promoted by Water. ... We report progress toward the biomimetic total synthesis of the ladder polyether gambierol. The FGH ring system has been synthesized in a 20 step longest linear sequence, via an endo-selective epoxide-opening cascade promoted by water. Chapter VI. Conclusion: Potential Implications of the Foregoing Work on the Biosynthesis of the Ladder Polyethers. We summarize lessons learned from in vitro emulation of the hypothesized biosynthesis of the ladder polyethers and speculate on the possibility of ring junction methylation subsequent to the epoxide-opening cascade step.
by Christopher J. Morten.
Ph.D.

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2

Vilotijević, Ivan. "Directing group-free endo-selective epoxide-opening cascades." Thesis, Massachusetts Institute of Technology, 2010. http://hdl.handle.net/1721.1/57703.

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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2010.
Vita. Cataloged from PDF version of thesis.
Includes bibliographical references (p. 108-112).
[image] The proposed biogenesis of the ladder polyethers features a dramatic series of epoxide opening reactions, elegantly accounts for the structural and stereochemical features of all related natural products, and, in principle, could significantly simplify the synthesis of these extraordinarily complex molecules. In practice, however, such cascades are strongly disfavored, and non-natural directing groups must be covalently attached to each epoxide to overcome this inherent bias. We report herein a general method for directing group-free cascades that also supports the postulated biosynthesis. The two salient aspects of this strategy are a single design principle (a template) and a promoter that both donates and accepts hydrogen bonds. Water is the superior promoter, and it is most effective at approximately pH 7.
by Ivan Vilotijević.
Ph.D.

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3

Halkina, Tamara. "Studies on the total synthesis of gambierol via endo-selective epoxide-opening cascades." Thesis, Massachusetts Institute of Technology, 2016. http://hdl.handle.net/1721.1/103508.

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Thesis: Ph. D. in Organic Chemistry, Massachusetts Institute of Technology, Department of Chemistry, 2016.
Vita. Cataloged from PDF version of thesis.
Includes bibliographical references.
Progress towards the total synthesis of gambierol inspired by the biosynthetic hypothesis for ladder polyethers is described. Syntheses of the ABCD and FGH fragments have been completed in 29 and 3 1 steps, respectively, using water-promoted endo-selective epoxide-opening cascades to construct the poly-THP motifs. The concentration and temperature effects in the waterpromoted cascades were examined, and an operationally simple protocol was developed for the synthesis of polycyclic cascade products on multigram scale. [diagram] A sulfone tether between the ABCD and FGH fragments was used to facilitate an intramolecular olefination via the Ramberg-Backlund reaction. The highly site-selective hydrogenation of the fragment coupling alkene in the presence of H-ring alkene was developed using Noyori's hydrogenation catalyst, and several ring E cyclization precursors were subsequently prepared from C21 ketone. Investigation of a variety of methods for the C21-0 bond construction revealed a remarkably general spiroketalization pathway, which was previously unprecedented in ladder polyether synthesis and invariably led to the isolation of undesired 6,6-spiroketal products under most conditions. We have hypothesized that the presence of the FG ring junction methyl group disfavors the desired cyclization by exerting destabilizing 1,3-diaxial strain onto the newly forming ring junction of the requisite oxepane. We have therefore proposed that future studies examine the reverse direction for the synthesis of ring E via C16-0 bond formation. This approach would require installation of the tertiary alcohol on ring F prior to cyclization and would thus avoid the undesired reactivity resulting from the steric effects of the FG ring junction methyl group. [diagram]
by Tamara Halkina.
Ph. D. in Organic Chemistry

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4

Geminiani, Lorenzo. "Synthetic studies towards a new fulvestrant analogue." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/10004/.

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A study towards the synthesis of a new fulvestrant analogue with improved bioavailability was carried out. In this work a twelve-step synthetic route starting from β-estradiol was optimized and a palladium (Pd)-catalyzed endo-selective Heck reaction for the functionalization of an advanced intermediate was investigated.

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5

Boussaha, Basma El Amel. "Response selection for end-to-end retrieval-based dialogue systems." Thesis, Nantes, 2019. http://www.theses.fr/2019NANT4080.

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Le besoin croissant en assistance humaine a poussé les chercheurs à développer des systèmes de dialogue automatiques, intelligents et infatigables qui conversent avec les humains dans un langage naturel pour devenir soit leurs assistants virtuels ou leurs compagnons. L’industrie des systèmes de dialogue est devenue populaire cette dernière décennie, ainsi, plusieurs systèmes ont été développés par des industriels comme des académiques. Dans le cadre de cette thèse, nous étudions les systèmes de dialogue basés sur la recherche de réponse qui cherchant la réponse la plus appropriée à la conversation parmi un ensemble de réponses prédéfini. Le défi majeur de ces systèmes est la compréhension de la conversation et l’identification des éléments qui décrivent le problème et la solution qui sont souvent implicites. La plupart des approches récentes sont basées sur des techniques d’apprentissage profond qui permettent de capturer des informations implicites. Souvent, ces approches sont complexes ou dépendent fortement du domaine. Nous proposons une approche de recherche de réponse de bout en bout, simple, efficace et indépendante du domaine et qui permet de capturer ces informations implicites. Nous effectuons également plusieurs analyses afin de déterminer des pistes d’amélioration
The increasing need of human assistance pushed researchers to develop automatic, smart and tireless dialogue systems that can converse with humans in natural language to be either their virtual assistant or their chat companion. The industry of dialogue systems has been very popular in the last decade and many systems from industry and academia have been developed. In this thesis, we study retrieval-based dialogue systems which aim to find the most appropriate response to the conversation among a set of predefined responses. The main challenge of these systems is to understand the conversation and identify the elements that describe the problem and the solution which are usually implicit. Most of the recent approaches are based on deep learning techniques which can automatically capture implicit information. However these approaches are either complex or domain dependent. We propose a simple, end-to-end and efficient retrieval-based dialogue system that first matches the response with the history of the conversation on the sequence-level and then we extend the system to multiple levels while keeping the architecture simple and domain independent. We perform several analyzes to determine possible improvements

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6

O'Neill, Finbarr Gerard. "Mathematical model of trawl cod-end geometry." Thesis, University of Aberdeen, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.265381.

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To ensure that the conservation regulations which govern fishing gears are effective, they must be based on an understanding of the process by which fish are selected. The region where most fish selection is considered to take place is the cod-end, the aftmost part of a trawl net and the region where the catch accumulates. In recent years, it has become increasingly apparent that fish selection in the cod-end is dependent on a range of physical, environmental and fish behavioural parameters. Essential to a study of any of these parameters is a knowledge of the cod-end geometry which is determined by the interaction of the water flow, the catch size and the design and physical characteristics of the netting. In this thesis a continuum model of the deformation of a class of axisymmetric networks is developed where the mesh elements are reflection symmetric, the mesh bars are extensible and where arbitrary membrane forces act in the plane of the net, normal to the edges of the mesh elements. When applied to the fishing industry this provides a continuum model of the geometry of an axisymmetric trawl cod-end made from netting of a generalized mesh shape. It is shown how mesh shapes that are of interest to the fishing industry can be investigated, and the geometry of cod-ends made from diamond shaped mesh under the influence of various types of pressure loads is examined in detail. A qualitative description of the hydrodynamic forces that act on the cod-end catch is presented and it is shown that the predictions based on this description are consistent with experimental results from a series of wind tunnel trials. Using this description of the hydrodynamic forces the effect on cod-end geometry of mesh resistance to opening which arises as a result of twine flexural rigidity is examined.

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7

Nawaz, Muhammad Asif. "How terrorism ends: the impact of lethality of terrorist groups on their longevity." Diss., Kansas State University, 2017. http://hdl.handle.net/2097/35788.

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Doctor of Philosophy
Security Studies Interdepartmental Program
Andrew G. Long
David R. Stone
This dissertation research examines the effect of organizational lethality on the longevity of terrorist groups. The current scholarship has sought to understand the demise of terrorist groups through means such as group success, government repression, negotiations, internal conflict, reorientation of goals, defeat, leadership decapitation and loss of public support. However, little research is available on the determinants of terrorists’ target selection and its implications for the group’s longevity. This study evaluates the targeting patterns and preferences of 480 terrorist groups that were operational between 1980 and 2011 and disaggre- gates the victims of all terrorist attacks into combatant versus non-combatant target-types. It is hypothesized that organizational lethality – defined as the average number of civilian killings generated by each group in its home-base country – is associated with negative group reputation, which results in faster group mortality. Popular support for violence, however, can influence and result from terrorism at the same time and has been found to be inherently endogenous by many previous studies. Therefore, a Seemingly Unrelated Bivariate Probit Model is employed to examine this endogenous relationship, and the results confirm that there is a significant correlation between negative group reputation and group mortality. Moreover, the study differentiates between terrorist group activity – defined as average at- tacks generated by a group – and group lethality, and employs the Cox Proportional Hazard Model to estimate group duration. The study includes covariates like group size, ideology, positive consistency reputation and other factors affecting group longevity and mortality. The results imply that organizational lethality is associated with higher political risks for terrorist groups and tends to backfire by decreasing their survival probability. However, on the other hand, the study finds that an escalation in terrorist activity (launching more attacks) significantly increase the group longevity over time. The results of this study are tested by conducting group-specific case studies on the Afghan and Pakistani Taliban in Pak- istan using information collected from the English language Pakistani newspaper archives, and Harmony Database from Combat Terrorism Center at West Point, NY.

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8

Residegan, Katayun. "Critical success factors for selecting ideas in front-end of SME." Thesis, KTH, Entreprenörskap och Innovation, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-188895.

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Front-end activities prior to the product and process development have been pointed out by studies to be an essential part in development of new products and processes. Here selecting ideas is found to be route cause of success and failures of the new product and process development outcomes. The existing studies concentrate on larger companies, where tools and processes often are not fitting into the SME which have different needs and settings and lack attention regarding effective and sustainable processes in the front-end. This thesis addresses the need for a more detailed view of the most important factors that influence selecting innovative ideas in SME, with a purpose to address these factors and improve them in the front end process of these companies. For this, by means of extensive literature study on SME, front-End and idea selection theories, a theoretical model for critical success factors for idea selection is developed, containing 21 factors. These factors are divided in main aspects of Shared vision, Innovation strategy, Leadership and management, Appropriate, structure and organization, Key individuals. Subsequently this model is tested in a case study of Bioteria Technologies AB in which the company’s idea selection process is analysed with the model. The empirical analysis and discussions resulted in learning about the status of the company against the factors from which propositions follow. The outcome of the study is a model that can be used for addressing what the challenges and opportunities are for the SME related to improving or adopting an idea selection phase.

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9

Himbert, Esther. "Analysis of German real estate funds: selection criteria for investment opportunities perspective." Thesis, KTH, Fastigheter och byggande, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-147656.

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This study is focused on real estate funds formed in Germany and has two major purposes: first to investigate the liquidity crisis and followed change of the legal framework for German real estate funds and secondly to demonstrate the impact on investment selection criteria of German real estate investment companies . By both quantitative and qualitative methods the thesis approaches those two different purposes. The quantitative part provides theoretical background about the construct of open-end and closed-end real estate funds and about the triggers and effects of the liquidity crisis. The qualitative part consists of an online survey that was sent to German real estate investment companies in which respondents indicated their preferred criteria for real estate investment opportunities. Furthermore telephone interviews on this topic were conducted with four German real estate investment experts. In the end the findings from the survey and the interviews are applied to a case study about a trophy asset in Luxembourg, in order to analyze if this property meets the investment criteria of German real estate funds. The survey and the conducted interviews indicate that German real estate investment companies have adapted to the risk-averse investment behaviour of investors and preferably make safe haven investments in terms of the investment style, the location of the real estate asset and the characteristics of the property itself and its tenants. The case study as well confirms this result.

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10

Battenfield, Sarah. "Genomic selection and association mapping for wheat processing and end-use quality." Diss., Kansas State University, 2015. http://hdl.handle.net/2097/35219.

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Doctor of Philosophy
Genetics Interdepartmental Program
Allan K. Fritz
Globally, wheat (Triticum aestivum L.) is the second most widely grown cereal grain and is primarily used as a food crop. To meet the demands for human consumption, cultivars must possess suitable end-use quality for release and acceptability. However, breeding for quality traits is often considered a secondary goal, largely due to amount of seed needed and overall expense of such testing. Without testing and selection, many undesirable materials tend to be advanced. Here we demonstrate two methods, mega-genome-wide association mapping and genomic selection, to enhance selection accuracy for quality traits in the CIMMYT bread wheat breeding program. The methods were developed using high-density SNPs detected from genotyping-by-sequencing and processing and end-use quality evaluations from unbalanced yield trial entries (n = 4,095) during 2009 to 2014, at Ciudad Obregon, Sonora, Mexico. Genome-wide association mapping, with covariates for population structure and kinship, was applied for each trait to each site-year individually and results were combined across years in a mega-analysis using an inverse variance, fixed effect model in JMP-Genomics. This method presents a new way to detect genes of interest within a breeding program and develop markers for selection of these traits, which can then be used in earlier generations. Genomic selection prediction models were developed using ridge regression, Gaussian kernel, partial least squares, elastic net, and random forest models in R. With these predictions genomic selection (GS) can be applied at earlier stages and undesirable materials culled before implementing expensive yield and quality screenings. In general, prediction accuracy increased over time as more data was available to train the model. Based on these prediction accuracies, we conclude that genomic selection can be a useful tool to facilitate earlier generation selection for end-use quality in CIMMYT bread wheat breeding. Genomic selection was conducted for processing and end-use quality traits in the Kansas hard red winter wheat breeding unit. Genomic predictions demonstrate increases in accuracy with added data over time. These data demonstrate that current genomic selection models will need more data to continue improvement in prediction accuracy.

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11

Bashir, Rabia. "Developing markers from BAC-End sequences to improve marker assisted selection in soybean /." Available to subscribers only, 2007. http://proquest.umi.com/pqdweb?did=1456299651&sid=2&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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12

Yoward, Paul James. "Spider sperm competition : the conduit/cul-de-sac hypothesis : a route to understanding or a dead end?" Thesis, University of York, 1996. http://etheses.whiterose.ac.uk/14176/.

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This thesis is an evaluation of the hypothesis that the spennathecae of spiders affects the sperm precedence patterns in a predictable way (Austad 1984). Spermathecae come in two varieties: cul-de-sac and conduit. Cul-de-sac spennathecae, according to the hypothesis, are supposed to lead to second male sperm priority and conduit to first male sperm priority . The hypothesis was evaluated both directly and indirectly. Direct measurements were made of paternity in two species, Pholcus phalangioides and Tetragnatha montana, both of which are cul-de-sac species. It was found that P. phalangioides complies with the predicted precedence pattern and thus does not disprove the hypothesis. This second male priority pattern was despite a much shorter mating time by second mating males. In T. montana no precedence pattern was found, with equal likelihood of first or second mating males of gaining paternity. There was in T. montana a possible influence of the duration of mating affecting the precedence pattern, with longer mating males gaining a higher paternity no matter what order they mated in. It is discussed whether or not this is due to sperm loading or genitalic stimulation (Eberhard 1985). Indirect evaluation of the hypothesis included an analysis of mating behaviour in Zygiella x-notata which is a conduit species and was chosen as a comparison to the two cul-de-sac species. In Z. x-notata it was found that there was no difference between mating duration in first and second mating males. Mating persistence is thus the same in first and second mating males, suggesting that the males cannot detect that the female is a denuded resource to second mating males. Hence first male priority may not be a factor in this species. Other indirect methods of evaluating the hypothesis involved charting the incidence of mate-guarding and mating-plugs. The expected pattern of mate-guarding was for conduit species to pre-mate guard and for cul-de-sac species to post-mate guard, because of the predicted sperm precedence patterns associated with the spermathecae. The predicted pattern was not found. In the case of mating-plugs it was predicted that these should be deployed by cul-de-sac species because it is in these species that second males are able to usurp paternity to a large extent. The opposite pattern was found with mating-plugs of various design being utilized by conduit species. It is postulated that mating-plugs are the mechanism by which first male priorities are established in conduit species, where this pattern is found. The absence of plugs in cul-de-sac species is possibly the reason that second males can cuckold. The additional data collected since 1984 reveal that patterns of paternity found in spiders seem to be more complex than was originally assumed by Austad (1984). Spermathecae are species-specific in character and this may reflect a species specificity in sperm precedence patterns. Thus the conduit I cul-de-sac dichotomy may not reflect a useful prediction of paternity patterns.

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13

Haapala, A. (Antti). "Paper machine white water treatment in channel flow:integration of passive deaeration and selective flotation." Doctoral thesis, Oulun yliopisto, 2010. http://urn.fi/urn:isbn:9789514263682.

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Abstract Gas removal from the papermaking process is currently a standard practice, whereas purification of the internal water circulation has become common only recently. Both unit processes have progressed greatly during recent decades and new concepts are constantly being developed. The aim of this thesis was to analyse the efficiency and applicability of a channel flow design introduced by Metso for passive white water deaeration and to study the dynamics of passive bubbly gas removal. In addition, separation of the detrimental process water components by selective flotation during deaeration was studied to add further functionality to the channel flow design. Turbulent mixing at the flow discharge and the consequent air entrainment were seen to limit the gas separation efficiency. Also, the properties of different white waters notably affect their deaeration through viscous forces, the concentration of surface active components and bubble-particle interactions. Thus similar levels of gas separation cannot be achieved with all process waters. The analysis showed that the drag of small microbubbles is mostly caused by hydrophobic contamination and the dispersed particles that readily attach to the bubbles. Correlations were derived based on experimental data to provide new information on the drag force experienced by small bubbles in white waters. Chemically unaided flotation of white water in the channel flow was shown to be efficient in separating hydrophobic contaminants that have adverse effects on paper machine production and product quality. Both good reductions in contaminant content and high selectivity in their removal were achieved. Channel flow with an overflow can be considered well suited for the first stage of froth separation, while further treatment of the channel flow reject may consist of a secondary flotation or other process that enables the recirculation of fines and fillers. Although a certain level of losses of fines and fillers must be expected, substantial fraction of these solid components can be returned to the process stream. The proposed multifunctional process, channel flow deaeration and frothing of white water, was seen to be straightforward, economical and feasible while also providing benefits in terms of total process efficiency that are not delivered by any current process scheme. The experimental parameters presented here regarding bubble dynamics and flotation efficiency can be used to achieve better models of these processes.

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14

Willrich, Niklas [Verfasser], Vladimir [Akademischer Betreuer] Spokoiny, Oleg [Akademischer Betreuer] Lepski, and Enno [Akademischer Betreuer] Mammen. "Resampling-based tuning of ordered model selection / Niklas Willrich. Gutachter: Vladimir Spokoiny ; Oleg Lepski ; Enno Mammen." Berlin : Mathematisch-Naturwissenschaftliche Fakultät, 2015. http://d-nb.info/108022954X/34.

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15

UMEMOTO, Takatoyo, та 貴豊梅本. "CAMI (Control, Agency, and Means-Ends Interview) による期待信念と授業選択, 学習行動の関連". 名古屋大学大学院教育発達科学研究科, 2010. http://hdl.handle.net/2237/16150.

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16

Cross, Lee W. "Design of Microwave Front-End Narrowband Filter and Limiter Components." Thesis, The University of Toledo, 2013. http://pqdtopen.proquest.com/#viewpdf?dispub=3588122.

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This dissertation proposes three novel bandpass filter structures to protect systems exposed to damaging levels of electromagnetic (EM) radiation from intentional and unintentional high-power microwave (HPM) sources. This is of interest because many commercial microwave communications and sensor systems are unprotected from high power levels. Novel technologies to harden front-end components must maintain existing system performance and cost. The proposed concepts all use low-cost printed circuit board (PCB) fabrication to create compact solutions that support high integration.

The first proposed filter achieves size reduction of 46% using a technology that is suitable for low-loss, narrowband filters that can handle high power levels. This is accomplished by reducing a substrate-integrated waveguide (SIW) loaded evanescent-mode bandpass filter to a half-mode SIW (HMSIW) structure. Demonstrated third-order SIW and HMSIW filters have 1.7 GHz center frequency and 0.2 GHz bandwidth. Simulation and measurements of the filters utilizing combline resonators prove the underlying principles.

The second proposed device combines a traditional microstrip bent hairpin filter with encapsulated gas plasma elements to create a filter-limiter: a novel narrowband filter with integral HPM limiter behavior. An equivalent circuit model is presented for the ac coupled plasma-shell components used in this dissertation, and parameter values were extracted from measured results and EM simulation. The theory of operation of the proposed filter-limiter was experimentally validated and key predictions were demonstrated including two modes of operation in the on state: a constant output power mode and constant attenuation mode at high power. A third-order filter-limiter with center frequency of 870 MHz was demonstrated. It operates passively from incident microwave energy, and can be primed with an external voltage source to reduce both limiter turn-on threshold power and output power variation during limiting. Limiter functionality has minimal impact on filter size, weight, performance, and cost.

The third proposed device demonstrates a large-area, light-weight plasma device that interacts with propagating X-band (8-12 GHz) microwave energy. The structure acts as a switchable EM aperture that can be integrated into a radome structure that shields enclosed antenna(s) from incident energy. Active elements are plasma-shells that are electrically excited by frequency selective surfaces (FSS) that are transparent to the frequency band of interest. The result is equivalent to large-area free-space plasma confined in a discrete layer. A novel structure was designed with the aid of full-wave simulation and was fabricated as a 76.2 mm square array. Transmission performance was tested across different drive voltages and incidence angles. Switchable attenuation of 7 dB was measured across the passband when driven with 1400 V_pp at 1 MHz. Plasma electron density was estimated to be 3.6 × 10¹² cm^-3 from theory and full-wave simulation. The proposed structure has potential for use on mobile platforms.

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17

Rodriguez, Ciro A. "Ball-nose end milling-development of criteria for automatic selection of spindle speed and feed rate /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487947501133616.

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18

Shiri, Ali Asghar. "End-user interaction with thesaurus-enhanced search interfaces : an evaluation of search term selection for query expansion." Thesis, University of Strathclyde, 2003. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=21521.

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A major challenge faced by end-users during the information search and retrieval process is the selection of search terms for query formulation and expansion. Thesauri are recognised as one source of search terms with the potential to assist users in the process of term selection. Research in search term selection, query expansion and interface evaluation has stressed the importance of providing end-users with terminological assistance. As the number of thesauri attached to information retrieval systems has grown, a range of interface facilities and features have been developed to aid users in formulating their queries. This study investigated end-user interaction with a thesaurus-enhanced search interface to evaluate their search term selection and query expansion behaviour. The main objectives of this study were: to evaluate how and to what extent a thesaurus-enhanced search interface assisted end-users in selecting search terms for query expansion, to ascertain users' attitude toward both the thesaurus and interface as tools for facilitating search term selection, and to identify searching and browsing behaviours of users interacting with a thesaurus-enhanced interface. The test environment involved the Ovid CAB Abstracts database, the CAB thesaurus, and 30 academic staff and postgraduate students with genuine search requests. The data gathering tools employed were pre-search questionnaires, screen capturing software, post-search questionnaires, and post-session interviews. The results demonstrated different patterns of thesaurus-based search term selection by academic staff and postgraduates. Academic staff with more extensive domain knowledge tended to select narrower terms whereas postgraduates more often chose related and broader terms. In general, all users selected a larger number of narrower and related terms for expanding their queries. The effect of topic characteristics such as topic complexity and topic familiarity on search behaviour was also investigated. It was shown that complex topics affected users' cognitive and physical moves, number of search terms selected and query expansion instances. Topic familiarity was also found to have an effect on users' browsing behaviour. An evaluation of users' perceptions of the interface indicated that usability was a factor affecting thesaurus browsing and navigating behaviour. This study was constrained by the limitations of the IR system utilised, the experimental design and the choice of subjects. However, this study can be viewed as the first investigation of variables such as topic complexity and topic familiarity within a thesaurus-enhanced search environment. The findings of this study contribute to research in the areas of user-centred search term selection, thesaurus-assisted query expansion and the evaluation of user interaction with IR search interfaces.

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19

Filho, Augusto Marcelino Lopes Dorneles. "Critérios na seleção de plásticos de engenharia para aplicações em veículos populares no Brasil." Universidade de São Paulo, 2006. http://www.teses.usp.br/teses/disponiveis/3/3149/tde-06092016-150247/.

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Este trabalho tem por objetivo propor alguns critérios básicos, para o desenvolvimento de plásticos de engenharia em aplicações, componentes e partes dos veículos chamados populares, particularmente no Brasil, em substituição a partes tradicionalmente usinadas, fundidas ou injetadas em ligas metálicas. A despeito da desconfiança que cerca alguns dos componentes em plásticos que se destinam às aplicações automotivas, (e uma das principais razões para isso, são as elevadas temperaturas presentes em algumas áreas do automóvel), as grandes indústrias do setor não deixam de conceber novos projetos em polímeros de alta performance, para aplicações tidas como críticas em termos de resistência geral. Os chamados plásticos de engenharia são preferivelmente escolhidos devido à sua fácil processabilidade, e sua flexibilidade em propiciar desenhos mais complexos, com boa estabilidade dimensional e uma excelente resistência à corrosão em ambientes de hostilidade química. No passado, as empresas claramente optavam pelos plásticos chamados de termofixos, que hoje estão quase esquecidos ou obsoletos (principalmente devido aos processamentos mais custosos e/ou mais lentos). Hoje são largamente substituídos pelos termoplásticos de engenharia. Atualmente, o consumo de plásticos em alguns carros brasileiros já alcança quase 130 kg de plásticos nos seus interiores e/ou exteriores (como o Ford KA, por exemplo), o que ajuda a reduzir o peso total do automóvel, aumentando a economia de combustível, reduzindo os custos de processos, aliada a uma excelente aparência superficial. Este trabalho versará sobre a possibilidade de se propor critérios mais objetivos na fase inicial de um processo de seleção de plásticos de engenharia (notadamente, poliamidas, acetais, poliésteres, e policarbonato), aumentando a eficácia da escolha e diminuindo custos (evitando erros e economizando tempo), como um guia prático de consulta para engenheiros e profissionais do setor automotivo brasileiro.
The main objective of this paper is to propose some basic economical and objective criteria for the engineering plastics development in applications, components and parts in the low-end cars segment (known in Brazil as popular cars), to replace traditional metallic machined, die-casted or injected parts. In spite of the lack of reliance in plastics components in automotive applications (one of them being the high temperature in the engine area), big industries in the sector always conceive new projects on high performance polymers for applications considered critical because of its general resistance. The named engineering plastics are preferably chosen due to its easy processing, complex design flexibility, with a good dimensional stability and an excellent resistance against corrosion in environments with chemical hostility. In the past, companies clearly selected the called thermo-stable plastics, almost forgotten or obsolete nowadays (mainly due to the high cost and/or slowness on processing). Today they are largely replaced by engineering thermoplastics. Nowadays, the consumption of plastics in Brazilian low-end cars already reached approximately 130 kg of plastics in their interior and/or exterior (like in Ford KA, for example), which helps to reduce total car weight, increasing the saving of fuel, mitigating process costs, besides to an excellent surface appearance. This paper will approach about the possibility of proposing more objective criteria in the initial phase of the engineering plastics selection (notably polyamides, acetals, polyesters, and polycarbonates), increasing the choice efficacy and diminishing costs (avoiding mistakes and saving time), as a practical consulting guide to engineers and professionals from the Brazilian automotive sector.

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Huang, Kelvin. "The Impact of Minimum Investment Barriers on Hedge Funds: Are Retail Investors Getting the Short End of Performance?" Thesis, Kingston, Ont. : [s.n.], 2008. http://hdl.handle.net/1974/1647.

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FRÖBERG, EMIL. "Exploring Idea Selection in Innovative Early- Stage Startups : A Framework for Analyzing Ideas in a Lean Development Context." Thesis, KTH, Skolan för industriell teknik och management (ITM), 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-279088.

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Innovation is a key factor for companies in order to survive in the long-term and to stay competitive. However, it can be challenging to know what ideas (or innovations) to pursue. Large incumbent companies can be slow to innovate, but startups on the other hand, are a great source of innovation. However, many startups fail. Starting a new company is risky, but a countervailing force has emerged called Lean Development. There is a strong need for research and studies on the subject of product development in a Lean Development context and the process of Idea Selection has been somewhat ignored in research. Idea Selection is a part of the Front End of Innovation and is often mentioned as an important factor for success in the innovation process. This study was aimed at creating a framework for Idea Selection, building on the intersection between the Front End of Innovation and the New Product and Process Development in a Lean Development context. The findings are based on current theory on Innovation, Idea Selection and Lean Development as well as a case study conducted at a Swedish insurance startup. The main conclusion of this study is a framework containing four themes: Reach, Impact, Confidence and Effort. By using this framework, startups can more easily decide on what ideas to pursue and thereby move quicker and achieve more success in the innovation process.
För ett företag är innovation en nyckelfaktor för långsiktig överlevnad och för att vara konkurrenskraftig. Det kan emellertid vara utmanande att veta vilka idéer (eller innovationer) som bör utforskas vidare och implementeras. Stora etablerade företag kan vara långsamma att innovera, men nystartade företag, startups, kännetecknas å andra sidan ofta av att ha stor innovationsförmåga. Men många startups misslyckas. Att starta ett nytt företag är riskabelt. För att minska den risken har något som kallas Lean Development växt fram. Det finns ett starkt behov av forskning och studier om produktutveckling i Lean Development-sammanhang och processen att välja ut idéer har ignorerats i forskning. Idéval är en del av Front End of Innovation och nämns ofta som en viktig faktor för framgång i innovationsprocessen. Denna studie syftar till att skapa ett ramverk för Idéval, som bygger på skärningspunkten mellan Front End of Innovation och New Product and Process Development ett Lean Development-sammanhang. Resultat är baserade på aktuell teori om Innovation, Idéval och Lean Development samt en fallstudie genomförd vid en svensk startup inom försäkringsbranschen. Den huvudsakliga slutsatsen i denna studie är ett ramverk som innehåller fyra teman: Reach, Impact, Confidence and Effort. Genom att använda detta ramverk kan nystartade företag lättare bestämma vilka idéer de ska gå vidare med och därmed bli mer snabbrörliga och uppnå mer framgång i innovationsprocessen.

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Humphries, Sarah S. Osborne Barbara. "An examination of the relationship between end of season conference rankings and the bowl game selection process in the Atlantic Coast Conference." Chapel Hill, N.C. : University of North Carolina at Chapel Hill, 2009. http://dc.lib.unc.edu/u?/etd,2738.

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Thesis (M.A.)--University of North Carolina at Chapel Hill, 2009.
Title from electronic title page (viewed Mar. 10, 2010). "... in partial fulfillment of the requirements for the degree of Master of Arts in the Department of Exercise and Sport Science Sport Administration." Discipline: Exercise and Sports Science; Department/School: Exercise and Sport Science.

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23

Wahl, Martin [Verfasser], and Enno [Akademischer Betreuer] Mammen. "On the Mod-Gaussian Convergence of a Sum over Primes and Estimation of Components and Variable Selection in High-Dimensional Complex Models / Martin Wahl ; Betreuer: Enno Mammen." Heidelberg : Universitätsbibliothek Heidelberg, 2015. http://d-nb.info/1180395905/34.

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Liu, Zhi-Hong. "Mixed-signal testing of integrated analog circuits and modules." Ohio : Ohio University, 1999. http://www.ohiolink.edu/etd/view.cgi?ohiou1181174339.

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Meier, Nicholas Alan. "Investigation of winter wheat sowing date management and genetic architecture of malting quality in winter barley and milling/baking performance in soft red winter wheat." Diss., Virginia Tech, 2020. http://hdl.handle.net/10919/96604.

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Wheat (Triticum aestivum, L) and barley (Hordeum vulgare) are widely grown as winter annual grains in a double crop rotation with soybean (Glycine max, L. Merr.) in much of the U.S. Improved management strategies and the development cultivars that meet the quality requirements of higher value end-use markets is important to increase production and profitability of winter annual grains and the double crop rotation in the Eastern U.S. In Chapter I, fifteen commercially relevant winter wheat genotypes ranging in maturity were sown in a split-plot design (sowing date=main plot, genotype=subplot) at three different sowing dates (considered to be 'very early' (20-28 days before recommended), 'early (6-11 days before recommended)', or 'recommended') and replicated three times at eight environments (site-year) from 2015-2018 in VA and KY. Grain yield, tiller estimation, heading date, protein, and 1000-kernel weight were assessed for each yield plot. At all environments, sowing earlier in the fall achieved an earlier (P<0.05) heading date, while grain yields varied depending on environment and genotype. Genotype by sowing date interactions were non-significant (P<0.05) at five site-years and significant (P<0.05) at three site-years. Molecular markers can be associated with phenotypic traits via quantitative trait loci (QTL) mapping, these markers can be used by breeders in marker assisted selection (MAS) to indirectly select phenotypic traits that are difficult or expensive to measure. In Chapter II, the genetic architecture of end-use quality is investigated in two soft red winter wheat bi-parental (Pioneer '25R47' / 'Jamestown' and Pioneer '26R46' / 'Tribute'). Both populations were genotyped with a public 90,000 wheat iSelect SNP-Array, grown over two crop seasons at two Virginia sites, evaluated for quality traits at the USDA-ARS Soft Wheat Quality Lab (SWQL), and analyzed with QTL mapping. This chapter describes a total of 24 putative QTL that were identified on 13 different chromosomes and associated with grain characteristics, milling, and/or baking performance along with phenotypic data for both populations, other putative QTL, and transgressive progeny with exceptional flour yield and cookie diameters. A region on 3A (Qfy.vt.3A.Jtwn) is a strong candidate to be utilized for MAS in soft red winter wheat breeding programs as it explained 6.9-10.3% (Pioneer 25R47 / Jamestown) and 4.6-17.0% (Pioneer 26R46 / Tribute) of the phenotypic variation for flour yield. In Chapter III, malt quality genetic structure was investigated in two winter 'malt x feed' doubled haploid barley breeding populations. Both populations were genotyped with the iSelect InﬁniumTM SNP assay consisting of 50,000 barley SNPs, grown in two to three Virginia environments (Blacksburg and Warsaw) during 2017 - 2019, and characterized for 11 phenotypic traits associated with malting quality. QTL mapping validated six previously reported regions (Mohammadi, et al., 2015, GrainGenes 3.0, 2019) that are strongly associated (LOD > 3.0) with relevant malt quality traits. Phenotypic variation for malt quality was largely and consistently explained by QTL on chromosomes 1H, 5H, and 7H in the Endeavor / VA09B-34 population and by two separate QTL on 1H in the Violetta / VA09B-34 population. A region on 4H corresponding with QDp.DiMo-4H, explained between 12.1 - 42.2% (Endeavor / VA09B-34) and 30.0 - 55.7% (Violetta / VA09B-34) of the phenotypic variation for diastatic power (DU). These QTL are recommended for MAS in order to aid breeding strategies that aim to select for improved malting characteristics in Eastern U.S. malt barley breeding material.
Doctor of Philosophy
Wheat (Triticum aestivum, L) and barley (Hordeum vulgare) are staple crops throughout the world, and are the third and fourth most produced cereals crop according to the FAO. Primarily grown for human consumption, wheat and barley provide a significant percentage of the nutritional requirements for the human populations. According to the United Nations, wheat contributes 20% of all calories consumed by humans. Barley is the primary ingredient used to make beer. Increased productivity of all cropping and livestock systems is required in order to feed a growing human population while also restoring and preserving natural ecosystems. This can be accomplished through breeding and improved cropping systems management. Planting of existing cropland more frequently is fundamental to the improvement of cropping system productivity. In much of the U.S. (southern two-thirds of the lower 48), annual winter grains such as wheat and barley can be grown over the winter and spring in between the typical corn (Zea mays subsp. mays) and soybean (Glycine max, L. Merr.) growing seasons. Therefore, producing three crops in two years, as opposed to only two. Only between 6 and 11 million acres are double cropped in the US annually, for perspective, in 2018, 89 million acres of both corn and soybeans, which can only grow in summer, were planted. Over half of the soybean (~45 million) acres in Midwestern and Southeastern states could support double cropping. This is a major opportunity to maximize output per unit area, freeing up less productive land to be restored as natural ecosystems, potentially increasing carbon sequestration and species biodiversity. Winter annual grains have a very similar composition (high carbohydrate, low protein and oil) to corn, and could fill similar end-use markets currently dominated by corn (i.e. ethanol or livestock feed). For double cropping to be more widely deployed, it must be more profitable. Increased profitability of growing three crops in two years as opposed to two must outweigh the added cost of planting, managing, harvesting, and marketing the additional winter crop. Therefore, it is important to investigate management strategies that could increase production per unit area and develop new winter annual cultivars with improved end-use characteristics in order to make the winter annual more desirable to the end-users. Chapter I investigates sowing winter wheat earlier in the fall (i.e. 1st week of Oct. or last week of Sept.) in order to achieve an earlier harvest in the spring and earlier soybean planting (yield decreases 0.5 to 1 bu/ac per day that sowing is delayed), while also offering other benefits such as better-established root systems going into winter, which improves water infiltration and reduces erosion. At all environments, sowing earlier in the fall achieved an earlier heading date, while grain yields varied depending on environment and genotype. Genotype by sowing date interactions were non-significant at five site-years and significant at three site-years. Chapters II and III investigate the genetic architecture of winter wheat and winter barley breeding populations for end-use quality traits (milling/baking and malting). This was done in order to identify molecular markers that could be used to screen breeding material for improved end-use quality. The markers could then be used to assist breeders in developing soft red winter wheat cultivars with greater flour yields/improved baking performance and winter malt barley cultivars that can be grown in the Eastern U.S. and are suitable for the craft beer market. Chapter II describes 24 genomic regions that influences milling/baking performance in two soft red winter wheat breeding populations. Chapter III describes 6 genomic regions that influence malting performance in two winter barley breeding populations.

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Johansson, Annie-Maj. "Undersökande arbetssätt i NO-undervisningen i grundskolans tidigare årskurser." Doctoral thesis, Stockholms universitet, Institutionen för matematikämnets och naturvetenskapsämnenas didaktik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-78835.

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This thesis deals with the use of inquiry-based approaches in primary school science. The aim is to investigate the goals and purposes that are constituted by the curriculum and by the teachers in interviews and through their teaching in the classroom. The results are used to develop conceptual tools that can be used by teachers’ in their work to support students’ learning of science when using an inquiry-based approach. The thesis is comprised of four papers. In paper one a comparative analysis is made of five Swedish national curricula for compulsory school regarding what students should learn about scientific inquiry. In paper two 20 teachers were interviewed about their own teaching using inquiry. Classroom interactions were filmed and analyzed in papers three and four, which examine how primary teachers use the various activities and purposes of the inquiry classroom to support learning progressions in science. The results of paper one show how the emphasis within and between the two goals of learning to carry out investigations and learning about the nature of science shifted and changed over time in the different curricula. Paper two describes the selective traditions and qualities that were emphasized in the teachers’ accounts of their own teaching. The results of papers three and four show how students need to be involved in the proximate and ultimate purposes of the teaching activities for progression to happen. The ultimate purposes are the scientific purposes for the lesson (as given by the teacher or by the curriculum), whereas the proximate purposes are the more student-centered purposes that through different activities should allow the students to relate their own experiences and language to the ultimate purpose. The results show the importance of proximate purposes working as ends-in-view in the sense of John Dewey, meaning that the students see the goal of the activity and that they are able to relate to their experiences and familiar language.

At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 1: In press. Paper 2: Manuscript. Paper 4: Manuscript.

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Abdullah, Jiwa. "QoS routing for mobile ad hoc networks using genetic algorithm." Thesis, Loughborough University, 2007. https://dspace.lboro.ac.uk/2134/35198.

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Mobile Ad Hoc Networks (MANETs) are a class of infrastructure less network architecture which are formed by a collection of mobile nodes that communicate with each other using multi-hop wireless links. They eliminate the need for central management, hence each node must operate cooperatively to successfully maintain the network. Each node performs as a source, a sink and a router. Future applications of MANETs are expected to be based on all-IP architecture, carrying a multitude of real-time multimedia applications such as voice, video and data. It would be necessary for MANETs to have an efficient routing and quality of service (QoS) mechanism to support diverse applications. This thesis proposes a set of cooperative protocols that provide support for QoS routing. The first is the on-demand, Non-Disjoint Multiple Routes Discovery protocol (NDMRD). NDMRD allows the establishment of multiple paths with node non-disjoint between source and destination node. It returns to the source a collection of routes with the QoS parameters. The second part of the protocol is the Node State Monitoring protocol for the purpose of monitoring, acquisition, dissemination and accumulation of QoS route information. The third part of the protocol implements the QoS route selection based on a Genetic Algorithm. The GA is implemented online with predetermined initial population and weighted-sum fitness function which operates simultaneously on the node bandwidth, media access delay, end to end delay and the node connectivity index (NCI). The term node connectivity index is a numerical value designed to predict comparatively the longest time a node-pair might be connected wirelessly.

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Beltrame, Rafael. "Desempenho silvicultural e seleção de clones de Eucalyptus spp. para a qualidade da madeira." Universidade Federal de Santa Maria, 2012. http://repositorio.ufsm.br/handle/1/3754.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
The study aimed to evaluate the silvicultural performance of Eucalyptus spp. clones and select superior clones with higher quality of the wood. The material used for the study was from a clonal test of interspecific hybrids of Eucalyptus spp., in the municipality of Tapes - state of Rio Grande do Sul, belonging to company CMPC Celulose Riograndense. The forest stand was established in August 2003, with initial spacing of 3.0 x 3.0 m, containing 138 clones. The clones were grouped by the diameter at breast height (DBH) and overall height (h), and 29 of them were selected for the study. For the sampling of trees DBH, h, bark thickness (EC), dynamic modulus of elasticity (Ed) using ultrasound and longitudinal residual strain (DRL) resulting from growth stresses. The DRL was measured in living trees with the extensometer method CIRAD-Fôret. Afterwards, 58 trees were felled and broken into logs to evaluate end splitting planks were taken to prepare speciments for wood physical and mechanical properties according to D 143-94 - ASTM (2000) standards. The end logs splitting (IRT) was evaluated in the field, covering the logs end during five days for subsequent measurement. The phenotypic variance components and indirect gain selection estimate for the clones in this study were determined by DRL, wood volume (Vsc), basic density (ρpond) and IRT. The clones showed enough genetic variability to be separated into groups according to DHB at three and seven years, and for h at seven years of age. The early selection at three years after planting can be used to identify Eucalyptus spp. clones with best growth. The DRL showed variability among clones, but no correlation with the dendrometric variables. The mean value for IRT was 0.46%. The DRL was highly correlated with TCL and IRT, however the ρpond and mechanical properties showed no correlations with the DRL. The clones belonging to group 1, which present the lowest levels for TCL and consequently lower IRT, can be considered potential for forest breeding programs. Clone selection performed by the variable DRL, Vsc, ρpond and IRT, provided satisfactory genetic gains, by improving the growth characteristics or improving quality of the wood.
DESEMPENHO SILVICULTURAL E SELEÇÃO DE CLONES DE Eucalyptus spp. PARA A QUALIDADE DA MADEIRA Autor: Rafael Beltrame Orientador: Dr. Clovis Roberto Haselein Data e Local da Defesa: Santa Maria, 14 de dezembro de 2012. O estudo teve como objetivos avaliar o desempenho silvicultural de clones de Eucalyptus spp. e selecionar clones superiores visando à qualidade da madeira. O material utilizado foi procedente de um teste clonal de híbridos interespecíficos de Eucalyptus spp., conduzido no município de Tapes-RS, pertencente à empresa CMPC Celulose Riograndense. O povoamento foi implantado em agosto de 2003, com espaçamento inicial de 3,0 x 3,0 m, contendo 138 clones. Os clones foram avaliados e agrupados quanto ao diâmetro à altura do peito (DAP) e altura total (h), selecionandose 29 deles para o estudo. Nas árvores, foram medidos o DAP, a h, a espessura de casca (EC), o módulo de elasticidade dinâmico (Ed) com auxílio do ultrassom e a deformação residual longitudinal (DRL) decorrente das tensões de crescimento. A DRL foi medida em árvores vivas, utilizando o extensômetro, pelo método CIRADFôret. Em seguida, 58 árvores foram abatidas e desdobradas em toras para avaliação das rachaduras de topo e confecção de amostras para a realização dos testes físicos e mecânicos, conforme a norma D 143-94 - ASTM (2000). O índice de rachaduras de topo das toras (IRT) foi avaliado a campo, ensacando as extremidades dessas por um período de cinco dias para posterior medição. A estimativa dos componentes da variância fenotípica e o ganho indireto de seleção para os clones do estudo foram determinadas por meio da DRL, volume sem casca (Vsc), massa específica básica ponderada (ρpond) e IRT. Os clones apresentaram variabilidade genética suficiente para serem separados em grupos quanto ao DAP, aos três e aos sete anos, e quanto à h das árvores, aos sete anos de idade. A seleção precoce aos três anos após o plantio pode ser empregada para identificar clones de Eucalyptus spp. com melhor vigor de crescimento. A DRL apresentou variabilidade entre os clones, porém não apresentou correlações com as variáveis dendrométricas. O valor médio do IRT foi de 0,46%. A DRL apresentou alta correlação com a TCL e o IRT, entretanto, a ρpond e as propriedades mecânicas não apresentaram correlações com a DRL. Os clones pertencentes ao grupo 1, por apresentarem os menores níveis para a TCL e, consequentemente, menores IRTs, podem ser considerados potenciais para programas de melhoramento genético florestal. A seleção de clones realizada por meio das variáveis DRL, Vsc, ρpond e IRT proporcionaram ganhos genéticos satisfatórios, tanto para o melhoramento das características de crescimento quanto para a qualidade da madeira.

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Acs, Andreas [Verfasser], Thomas [Akademischer Betreuer] Winkler, and Thomas [Gutachter] Winkler. "A model for interclonal competition in the germinal center: Dynamic selection processes by-pass the affinity dead-end of low affinity anti-NP specific B cells / Andreas Acs ; Gutachter: Thomas Winkler ; Betreuer: Thomas Winkler." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2019. http://d-nb.info/1179450434/34.

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Bonaldi, Elisa. "Strategy and Method for the Elaboration, Development and Optimization of an Innovative Recycling Process." Thesis, Université de Lorraine, 2015. http://www.theses.fr/2015LORR0167/document.

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Анотація:

Les réglementations sur le recyclage des produits, mais aussi le développement de l‘écoconception, obligent les industriels à rechercher des solutions de recyclage pour leurs produits en fin de vie. Les préoccupations environnementales croissantes dans l’industrie créent de nouvelles opportunités d’affaires et nécessitent des changements d’organisation pour accompagner la transition vers des activités industrielles plus durables. Une activité industrielle de recyclage de matières issues de la fin de vie d’un produit, se déroule idéalement avec la participation de différents partenaires industriels dans le cadre d’un projet collaboratif. Cela permet de développer une nouvelle supply chain de recyclage et de concevoir un nouveau produit, fabriqué grâce à cette supply chain. Les projets collaboratifs de R&D permettent de rassembler des compétences complémentaires dans le but de proposer des solutions pour accroitre le taux de recyclage d’une matière dans le domaine considéré. Aujourd’hui, les expériences de projets collaboratifs existent créant de nouvelles opportunités de marché dans l’industrie du recyclage. Cependant, nous observons qu’il n’existe pas de méthode opérationnelle permettant de guider les industriels dans la définition d’un projet collaboratif de recyclage. De plus, la sélection des partenaires pour de tels projets est une réelle difficulté pour les industriels. En effet, les valeurs apportées par les partenaires créent l’intérêt du projet et favorise le succès de la collaboration. Cependant, nous constatons qu’il n’existe pas de méthode dans le cadre du recyclage industriel pour faire un choix efficace de partenaires de R&D sur un projet collaboratif. Une revue de la littérature est présentée, pour connaitre l’état de l’art industriel et scientifique, avec un éclairage sur les meilleures pratiques existantes de façon à les prendre en compte et les intégrer, afin de proposer une contribution originale. A partir de cette revue de l’état de l’art, nous mettons en évidence un manque de méthode associant les organisations de projets collaboratifs R&D et le développement de supply chain de recyclage ; cela contribue à donner une posture originale à notre recherche. Notre contribution est de proposer une combinaison de méthodes pour accompagner les industriels dans la définition d’un projet collaboratif pour la mise en place d’une activité de recyclage. • La première méthode facilite la compréhension des mécanismes d’une industrie émergeante du recyclage, agissant simultanément sur l’impact environnemental, en recyclant les produits en fin de vie, et sur la compétitivité d’une entreprise, par sa différenciation vers de nouvelles activités industrielles. • La deuxième méthode développée est une aide pour le chef de projet R&D lors de la définition d’un « projet collaboratif de recyclage », avec la spécification du marché, du produit recyclé et de la structure projetée de la filière de recyclage. • Nous développons également la question de la sélection des partenaires d’un projet collaboratif de R&D dans le domaine du recyclage, en proposant une méthode d’évaluation ainsi que la définition de critères adaptés à ce nouveau contexte. Sur ce point, nous utilisons les techniques d’aide à la décision multicritères que nous combinons, afin d’aider les industriels dans ce processus de sélection. Une étude de cas est développée concernant l’industrie française du recyclage textile, ainsi qu’un projet de R&D collaboratif impliquant l’utilisation de matières premières recyclables provenant des véhicules hors d’usage et de vêtements fin de vie, pour l’éco-conception d’un produit nouveau. L’application de la combinaison des méthodes proposées, conduites dans le cadre d’un projet de recyclage spécifique, permet de discuter les premiers résultats et d’ouvrir ce sujet sur des perspectives de recherche à venir
Regulations on product recycling rates, but also growing consciousness on the importance of eco-design, enforce industrials to seek for solutions to recycle their products at their end of life. Growing environmental concerns in the industry allow new business opportunities and require organizational changes to support transition toward more sustainable industrial activities. Building a recycling industrial activity for materials coming from end of life products is a great challenge that requires an analysis of the opportunities and threats and the added value of industrial partners, in the scope of a collaborative project (or a collaborative network). This kind of projects aims at designing a new recycling supply chain and to design a new product that will be manufactured by this supply chain. R&D collaborative projects enable to gather complementary competencies in order to propose solutions to increase the recycling rate on the territory. Nowadays, experiences such as collaborative projects are witnessed, giving various new business possibilities in the recycling industry. However, a literature review we have performed points out that there is no existing method permitting to analyze the opportunity of a recycling value chain and to guide industrials in the definition of a “recycling collaborative project”. Moreover, for such projects, the selection of the partners is of great issue for the industrials. Indeed, the values brought by the partners make the interest of the project and favor the success of the collaboration. However, there is no existing method to choose R&D collaborative project partners efficiently in the scope of the recycling industry. A literature review presents the industrial and scientific state of the art and highlights the existing best practices in order to take them into account for the proposal of an original contribution. From the state of the art we can highlight a lack of methods that would associate R&D collaborative project organizations with the development of recycling supply chains; this positioning contributes to the originality of the work realized. Our contribution is to propose three methods to help industrials to define a collaborative project for the design and building of a new recycling supply chain: • The first method we propose facilitates the understanding of a recycling emerging industry mechanisms, act simultaneously on the environmental impact by recycling end of life products and on the business competitiveness by differentiation in new industrial activities. • The second method we developed must helps recycling R&D project managers to define a “recycling collaborative project”, the target market, the recycled product that will be manufactured and the potential structure of the future supply chain. • The third method is related to the question of partner selection with the proposal of a ranking method and the definitions of adapted criteria for such selections. In this respect we used Multi-Criteria Decision Making (MCDM) techniques to help industrials in this selection process. A case study is developed on the French textile recycling industry and a R&D collaborative project that introduces recyclable raw material from end of life vehicles and garments, for the development of a new product. An application of our research is conducted on a specific recycling collaborative project in order to discuss the initial results, and perspectives are highlighted for further research investigations

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31

Chen, Kai-Chi, and 陳楷奇. "Catalyst-Controlled Selective 7-exo-dig and 8-endo-dig Cyclization of Triazol-1-ylbenzamide for the Synthesis of Benzotriazolodiazepin-6-ones and Benzotriazolodiazocin-7-ones." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/hp8s9m.

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Анотація:

碩士
國立交通大學
應用化學系碩博士班
107
A regioselective and efficient synthesis of both innovative 1,2,3-triazole-fused-1,5-benzodiazocinones and 1,2,3-triazole-fused-1,5-benzodiazpinones through intramolecular cyclization of substituted ethynyl triazoyl amide were explored. A vital precursor 5-iodo-1,2,3-triazole benzoate was obtained from substituted 2-azido benzoic acid esters in a single step through a Copper-Catalyzed Azide−Alkyne Cycloaddition (CuAAC) reaction using a CuI/NBS catalytic system. A carbon−carbon triple bond was installed through a Sonogashira coupling reaction by kinds of terminal alkynes. The 1,4,5-substituted ethynyl triazoyl benzoate was then underwent hydrolyzation and amidation. Finally, the 1,4,5-substituted ethynyl triazoyl benzamide were cyclized by a Pd(PPh3)4 or AgOTf mediated intramolecular cyclization to aﬀord 7-exo-dig 1,2,3-triazole-fused-1,5-benzodiazpinones or 8-endo-dig 1,2,3-triazole-fused-1,5- benzodiazocinones individually.

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32

Lording, William James. "A deeper understanding of the Diels–Alder reaction." Phd thesis, 2010. http://hdl.handle.net/1885/11776.

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The Diels-Alder reaction was discovered in 1928 and has become the most efficient and practical method for the synthesis of six-membered carbocyclic and heterocyclic rings. This thesis comprises three chapters of results and discussion with the Diels-Alder reaction as a theme. Chapter 2 details an investigation of endo:exo selectivity in the Diels-Alder reactions of 1,3-butadiene. Chapter 3 explores aspects of the intramolecular Diels-Alder reactions of some substituted 1,3,8-nonatrienes, and Chapter 4 describes the domino Diels-Alder reactions of 1,4-diiodo-1,3-butadiene. The Diels-Alder reaction is powerful, general, and widely used in chemical synthesis, and it is well known that many Diels-Alder reactions exhibit endo selectivity, in accord with Alder’s empirical rule. The origins of endo:exo selectivity in the Diels-Alder reaction, however, are not completely understood and there is a dearth of experimental evidence concerning the Diels-Alder reactions of the archetypal 1,3-diene, 1,3- butadiene. Chapter 2 describes a study of the Diels-Alder reactions of an isotopically labelled 1,3-butadiene with a range of simple dienophiles, allowing the endo:exo selectivities of these important reactions to be determined for the first time. The experimental data shed light on the origins of endo:exo selectivity in the Diels-Alder reaction and will serve as an important reference for future computational investigations in this area. The intramolecular Diels-Alder reaction shares many of the virtues of its intermolecular counterpart, however its use in chemical synthesis is limited because intramolecular Diels-Alder reactivity and stereoselectivity are often governed by subtle factors, and can be very difficult to predict. As part of a comprehensive experimental and computational collaboration, Chapter 3 describes an investigation of the heat and Lewis acid promoted intramolecular Diels-Alder reactions of some ether tethered 1,3,8-nonatrienes. Also presented are the results of a rate study and a kinetic isotope effect study involving the intramolecular Diels-Alder reactions of some 1,3,8-nonatrienes. The experimental data are analysed and compared with predicted stereoselectivities, activation barriers and kinetic isotope effects obtained from computational modelling. Increased efficiency in chemical synthesis conserves resources, reduces waste, and saves time and money. Domino reactions are particularly efficient processes, which can generate complex products from simple reactants. Chapter 4 describes an investigation of the domino Diels-Alder reactions of (1E,3E)-1,4-diiodo-1,3-butadiene with maleimide dienophiles, through which a family of bicyclo[2.2.2]oct-2-ene derivatives are produced in one high yielding and stereoselective synthetic step.

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33

Jian-Liang, Lin, and 林建良. "The Adverse Selection Issue and Strategy for High-End Market." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/28685399253419532674.

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Анотація:

碩士
中原大學
企業管理研究所
98
This study starts at the observation of the small and medium enterprises. Small and medium enterprises are the main force of Taiwan economics development; they do a lot of important contributions for Taiwan. The flourishing of the small and medium enterprises just like the two sides of one coin. In manufacturing stage, the disbarndm -ent of New Eastern Corporation result in more division of labor and high growth of market. And then, because of the lower entry barriers and more transparent product information, the window covering industry become highly competing. In this situation, because of asymmetric information – consumers don’t understand the mechanism of component of window covering – the high-end corporations easily lead to adverse selection stuff. This essay use A Company as case study , the following will illustrate the two main topics: 1. the adverse selection issue in the window covering industry 2. how the A Company use relative price mechanism to separate market and overcome the adverse selection problem.

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34

Grünling, Nicolas. "Fuzzy front-end of entrepreneurship: developing a business idea selection framework." Master's thesis, 2017. http://hdl.handle.net/10362/23381.

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Анотація:

With an emerging and steady growing “startup industry” there is also an increasing amount of people collecting several business ideas aiming to become an entrepreneur. As founding can be a big step especially in professional life and is mostly connected with an investment of time and money, an upfront evaluation of one’s business ideas is crucial. Therefore, the purpose of this work is to develop a framework in order to support the evaluation of several business ideas in order to select the one to pursue.

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35

Chien, Yulian, and 簡郁蓮. "Exploring Retail Travel Agents Decision Making of Selecting Wholesalers: A Means-end Chain Approach." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/16878535285915170167.

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Анотація:

碩士
靜宜大學
管理碩士在職專班
99
With the development of science and technology, as well as increasing diversity of social values, the management of the travel industry in Taiwan and travelers’ spending attitudes have changed dramatically. This study explores the decision- making processes of Taiwan’s retail travel agencies when choosing to cooperate with the wholesale travel agencies. The research purposes are: 1) to understand the attributes, results, and value of the decision-making for the retail travel industry when choosing to cooperate with the wholesale travel industry; 2) to explore the consumer cognition structures in different positions such as the managers, salespersons, and operational personnel of the retail travel agencies. In this study, the Laddering Technique was used to interview 20 employees of retail travel agencies in Taichung City. After data collected, the researcher applied the “Means-End Chain” to analyze. The findings of this study showed that most of the retail travel agents paid more attention to the three attributes that are “products,” “salesperson,” and “price” in the choice of the Japan travel package product sets. The “result” attributes emphasized that high customer satisfaction, increasing revenues, job stability. The “ultimate value” attribute highlighted in “sense of security,” “sense of achievement,” and “self-realization.” The concrete and effective results of the B2B (Business to Business) model of consumer perception decision-making approach would help travel agencies to establish marketing strategies.

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36

Tsai, Meng-Chieh, and 蔡孟潔. "Selection of optimum cutting parameter for end-millin high speed cutting SKD61 mold steel." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/qn83ey.

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Анотація:

碩士
國立虎尾科技大學
創意工程與精密科技研究所在職專班
98
This study aims at producing an optimal cutting-parameter design for a finishing process for high-speed end milling using the grey relational analysis. The workpiece materials is SKD61 tool steel.The major performance indices chosen to evaluate the workpiece quality are surface roughness and surface waviness. The Taguchi method was used to produce parameter design for all experimental trials and the multiple performance characteristics(MPC)were evaluated using S/N ratio. The grey relational analysis was then used to convert the MPC into a single performance index. The Optimum design can be found by the analysis of variance and control factors response table on the single performance index. The confirmation results show that the surface roughness and surface waviness were significantly improved by the optimum design predicted by the grey relational analysis.

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37

SRIPHUEK, NATNAREE, and 邱芳菱. "Electronic and Steric Effects of Vinyl Silane-based Selective Chain Transfer Agents by End-Functionalization of Syndiotactic Poly(4-methylstyrene)." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/crv8bg.

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Анотація:

碩士
國立中正大學
化學工程研究所
106
The achievement of effective molecular weight controls in the preparation of syndiospecific polystyrene (sPS) derivatives remains a necessary challenge approaching the new applications. Conducting polymerization in the presence of selective chain transfer agents is an effective method to control the molecular weight of polymers. The molecular weight of polymers is further affected by using various selective chain transfer agents. Structurally well-defined end-functionalized syndiotactic poly(4-methylstyrene) (sPMS) were prepared by conducting a simultaneous selective chain transfer reaction during the syndiospecific polymerization of 4-methylstyrene with various vinylsilane-based selective chain transfer agents using Cp*Ti(OMe)3/MAO as the catalyst. Our results show that silyl chain transfer agents carrying bulky substituent will retard the incorporation rate of vinyl silane resulting in the generation of sPMS with higher molecular weight. By contrast, silyl chain transfer agents carrying electron donating substituents provide sPMS with lower molecular weight and with a larger chain transfer constant. In contrast, silyl chain transfer agents with electron withdrawing substituents give sPMS with high polymer molecular weight and with a small chain transfer constant. Therefore, the steric and electronic effects of selective chain transfer agent can be used as a synthetic tool for molecular weight control during syndiospecific polymerization of styrene.

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38

Dusabeyezu, Etienne. "Closing Gacaca─analysing Rwanda’s challenges with regard to the end of Gacaca courts." 2013. http://hdl.handle.net/11394/3500.

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Анотація:

Magister Legum - LLM
In Rwanda, Gacaca courts, community-based traditional courts, were alternative solution of dealing with the legacy of genocide after the failure of modern model of justice. In 2012, Gacaca courts were repealed by the Organic Law 04 of 2012. These courts left behind a large number of cases which include, inter alia, suspects ranged within first category, new cases of those who were or will be extradited from ICTR or other countries, thousands of perpetrators tried in absentia while abroad that have the right to file opposition as well as applications for review lodged against their judgements. Today, all of these cases fall under the jurisdiction of ordinary courts along with ordinary criminal and civil litigations. This causes practical challenges of inability of domestic courts to deal with the huge number of cases. Besides, the organic Law 04 of 2012 that terminates Gacaca courts provides mechanisms to deal with other issues related to the end of Gacaca courts. However, these mechanisms result in unequal treatment of genocide suspects and violate the victims’ rights. This may lead to qualify this law as discriminatory and unjust provision. Furthermore, this law remains silent vis-à-vis the issue of enforcement of sentences rendered against those tried in absentia while abroad and the issue of reparations. Despite the mechanisms set forth to deal with all those cases and other issues left behind by Gacaca courts, serious challenges remain. Confronting these challenges needs international cooperation to bring genocide perpetrators to trial, administrative schemes for reparations as well as legal harmonisation to adapt the domestic legislation to the post-Gacaca situation.

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39

Ko-FanTsai and 蔡克凡. "Laser cavity design and numerical study for selective generation of nearly nondiffracting Mathieu-Gauss Modes in end-pumped solid-state lasers." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/43752148463047609851.

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40

Hsiao, Hao-jen, and 蕭浩然. "End-Functionalization of Syndiotactic Polystyrene and Preparations of Syndiotactic Polystyrene Based Stereoregular Diblock Copolymers via the Vinylsilane-Induced Selective Chain Transfer Reaction." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/43793821960946194780.

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Анотація:

碩士
國立中正大學
化學工程所
97
Syndiotactic polystyrene (sPS) possesses many good properties, including a high melting temperature, a high glass transition temperature, high crystallinity, good hardness and a fast crystallization rate, to be used as a high performance engineering plastic. However, the high crystallinity of sPS also results in brittleness and low impact strength which may substantially limit the commercial applications of sPS. As the impact strength of sPS has been demonstrated to improve by linking or grafting with other polymer block, this research is aiming for the development of new methods that can lead to the successfully preparation of sPS-based diblock copolymers. By conducting the syndiospecific 4-chlorostyrene and 4-fluorostyrene polymerization using dimethylphenylvinylsilane (DMPhVS) as the chain transfer agent, vinylsilane end-capped syndiotactic poly-4-chlorostyrene (sP4CS) and vinylsilane end-capped syndiotactic poly-4-fluorostyrene (sP4FS) can be selectively produced by using Cp*Ti(OMe)3/MAO as the catalyst. The resulting end-capped polymers contain the uniform vinylsilane end group; thus, can be used as the end-functionalized stereoregular prepolymer for conducting subsequent postpolymerization for the preparation of sP4CS- and sP4FS-based stereoregular diblock copolymers. . Accordingly, we have successfully prepared the sP4CS-b-PLLA by conducting ring opening polymerization (ROP) of DL-lactide using the hydroxy-capped sP4CS as the macroinitiator. The sP4FS-b-aPS, on the other hand, can be selectively produced by conducting living radical (ATRP) polymerization of styrene using α-bromoisobutyl end-capped sP4FS as the macroinitiator. The diblock copolymers prepared by these new synthetic methods have been found to possess well-defined chemical structures (uniform block lengths and narrow ranges of molecular weight distribution) to be used in the self-assembly studies for displaying consistent nanomorphologies as revealed by TEM analyses

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41

Chiu, Chi-Yuan, and 邱啟員. "Investigating the Perceived Values of Preservice Prescool Educators in Selecting Preschools in Kaohsiung City via A Means-End Chain Approach." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/uu79r4.

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Анотація:

博士
義守大學
資訊工程學系
104
The merge of kindergartens and nurseries is an important revolution of preschool education policy for children below 6 years old. The early childhood educare institution has been restructured as “preschool” from “kindergarten” and “nurseries”. The new educational regulation has a great influence on the preschool from the stipulation of software and hardware facilities and equipment to the engagement of preschool educators. In the past, before the merged system of preschool education was implemented, the regulation regarding children enrollment and teacher-student ratio were not as strict as that of current preschool; the restructured preschools not only need to work under the enrollment pressure, but also need to face the approval issues of preschool educators. The pre-preschool educators are referred to the pre-graduated students who study in related departments of preschool education and childhood care, complete the educational practices which measure up Early Childhood Education and Care Act in 2013, and prepare to work in preschools after the merged kindergartens and nursery schools was implemented in 2012. This study observed two relevant issues: First, when interviewing some students from Preschool Education Department about their work orientation, many students were not willing to work in their major-related jobs after graduation; Second, practitioners managing private preschools after 2013 have perceived that the hiring of preschool educator has become a key successful element operating private preschools, which is also an important issue to be explored. Based on the issues mentioned above, this study aims to conduct an in-depth laddering interview to the pre-preschool educators in Kaohsiung and Pingtung areas and analyze data to identify their perceived values of choosing private preschools. This study interviewed 60 pre-preschool educators who major in preschool education, childhood care, and the center of cultivating preschool teachers. Among them, 50 were valid interviewees, including 3 males and 47 females, which shows a high female proportion; besides, 31 (62%) interviewees expressed that they were willing to work in the private preschools after graduation while 19 (38%) interviewees were not, which shows nearly 40 percent of them have no intention to work in private preschools in the future. Through Means-End Chain (MEC) method, three research coders concluded and named 47 relevant elements from the collected data of 50 interviewees with a high reliability, including 24 attributes (A), 10 consequences (C), and 13 values (V). In addition, they depicted the Hierarchical Value Map by the formulated “attribute-consequence-value” links. The critical link paths were filtered by the corresponding counts higher than the [A→C→V] cutoff value, which leads to three [A→C→V] and one [C→V] key linking paths related to why the subjects chose to work in the private preschools. Key link paths include [A14] good preschool working environment→[C3] increase the practice and experience of classroom management→[V1] increase the competency and range in professional education and care, [A17] comprehensive software and hardware devices→[C3] increase the practice and experience of classroom management→[V1] increase the competence and range of professional education and care, [A6] have open and multivariate teaching methods→[C3] increase the practice an experience of classroom management→[V1] increase the competence and range of professional education and care as well as [C5] have practiced teaching experience→[V1] increase the competence and range of professional education and care. The study suggests that the preschool managers can offer more teaching and practicing chances to the undergraduates for accumulating experiences, which can efficiently improve their practical experience of classroom management and increase their competence in education and care and wide perceive value. In contrast, the preschool educators should enhance their knowledge of related majors and diversify their learning and development. During the educational practice period, they should cooperate with the internship preschools, initiatively strive for teaching opportunities and improve the practical experience of classroom management; furthermore, they can share the practical experience among their colleagues to know more demands and changes of preschool educational environment so that they can increase their adaptive capacity in workplace. At last, during the interview, this research found a gap between their work intention for not to be preschool educators and the actual situations. As a result, this is a research limitation that can be narrowed in the future research by investigating whether they have sufficient understanding about their preschool jobs during their internships and the corresponding influences on future work intention. For examples, a comparative analysis on the research gap aiming at the service intentions of working in private preschools, or reversely infer the perceived values of private preschools.

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42

Simões, Carla L. "Integrating environmental and economic tools into product development." Doctoral thesis, 2014. http://hdl.handle.net/1822/35368.

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Анотація:

Tese de Doutoramento Programa Doutoral em Ciência e Engenharia de Polímeros e Compósitos
Specifications of new products have become increasingly more demanding in terms of price, performance, reliability, and consumer safety. Additionafly, environmental legislation has become a powerful driver for industry. As a consequence, over the past decades the plastic industry has strived to ensure adequate environmental and economic planning and optimization of its products. This particularly applies to the composites industry, due, for instance, to limitations in mechanical recycling of post-used composite parts. Sustainabie development requires quantitative methods to measure and compare the environmental, economic and social impacts of human activities for the provision of products. Life cycle thinking originated from the awareness that any product, process or activity has an effect on those impacts, from the moment raw materiais are extracted from nature until they end their service life, and return to nature. Life Cycie Assessment (LCA) and Life Cycle Costing (LCC) are sustainable tools that consider the fulI life cycle (LC) of a product. jOA evaluates the environmental impacts attributable to the LC of a product. On the other hand, LCC is the equivalent of LCA from an economic perspective. This thesis is focused on the integration of environmentai and economic tools into the product development cycle. Specifically, its main goal was to employ adequate environmental and economic methodologies in the product development process of fibre reinforced polymer (FRP) composite non-mobile structures, with particular emphasis given to the integration of LCA and LCC tools. An additional goal was to analyse alternative material and end-of-life (E0L) treatment scenarios, as well as the effect of externai conditions, such as fluctuations in crude oil price. In this context, an exhaustive literature review was conducted in order to define the LCNLCC integrated framework to be used in this work. The adopted LCA/LCC integrated model was then applied in three different non-mobile structure FRP composite case studies: Iighting columns, anti-glare Iamellae and storage tanks. A benchmark study comparing the use FRP composites with alternative conventional materiais was also done. Finally, alternative material and EoL treatment scenarios, as well as the effect of fluctuations in the crude oil price, were considered, in order to analyse the sensitivity of the results to external conditions. A deeper understanding of the incorporation of the LCA/LCC integrated model into the product development process was accomplished with this work. It was possible to recognize that the overali goal of a LCA/LCC integrated model study is to identify environmental and economic win-win and trade-off situations related to the fuli LC of a given product system. Undoubtediy, some uncertainties are associated to this study (such as parameter, scenario and modei uncertainties); however, the results can stiil be used as guidelines in product development, namely in material selection, processing technology selection, E0L management, strategic planning, and marketing.
As especificações de novos produtos têm vindo a tornar-se cada vez mais exigentes em termos de preço, desempenho, confiança e segurança dos consumidores. Além disso, a legislação ambiental tornou-se um vector determinante para a indústria. Como consequência, nas últimas décadas, a indústria de plásticos tem-se esforçado para garantir um planeamento e otimização ambiental e económico adequado dos seus produtos. Isto aplica-se, em particular, à indústria de compósitos, devido, por exemplo, às limitações na reciclagem mecânica de peças em materiais compósitos em fim-de-vida. O desenvolvimento sustentável exige métodos quantitativos para medir e comparar os impactos ambientais, económicos e sociais das atividades humanas envolvidas no fornecimento de produtos. O conceito de ciclo de vida fortalece a consciência que qualquer produto, processo ou atividade tem um efeito sobre esses impactos, desde que suas matérias-primas são extraídas da natureza até o fim de sua vida útil, quando são devolvidos à natureza Avaliação do Ciclo de Vida (ACV) e Avaliação de Custos do Ciclo de Vida (ACCV) são ferramentas sustentáveis que consideram o ciclo de vida (CV) completo de um produto. A ACV avalia os impactos ambientais atribuíveis ao CV de um produto. Por outro lado, a ACCV é o equivalente da ACV numa perspetiva económica. Esta tese foca-se na integração de ferramentas ambientais e económicas no ciclo de desenvolvimento do produto. O principal objectivo foi integrar metodologias ambientais e económicas adequadas no desenvolvimento de estruturas não-móveis de compósitos políméricos reforçados com fibra (PRF), com particular ênfase na integração das ferramentas de ACV e ACCV. Um objetivo adicional deste estudo foi analisar cenários alternativos de material e tratamento de fim-de-vida, assim como o efeito de condições externas tais como flutuações do preço do petróleo. Neste contexto, fez-se uma revisão exaustiva da literatura a fim de definir o âmbito da integração ACV/ACCV a utilizar neste trabalho. O modelo integrado ACV/ACCV adotado foi aplicado em três estruturas não-móveis de compósitos PRF: colunas de iluminação, lamelas anti-encadeamento e tanques de armazenamento. Foi também feito um estudo de "benchmark" comparando a utilização deste material e de materiais convencionais alternativos. Finalmente foram estudados cenários alternativos de materiais e tratamentos de fim-de-vida, bem como o efeito das flutuações do preço do petróleo, a fim de analisar a sensibilidade dos resultados a condições externas. O trabalho realizado permitiu adquirir uma mais profunda compreensão das vantagens do modelo integrado ACV/ACCV no processo de desenvolvimento do produto. Também permitiu reconhecer que o objetivo global de um estudo integrado ACV/ACCV é identificar, numa visão ambiental e económica, as situações "completamente preferíveis" ("win-win") e "de compromisso" ('trade-off) relacionadas com o CV completo de um determinado sistema de produto. Este estudo incorpora incertezas (por exemplo, as correspondentes a parâmetros, cenários e modelos); no entanto, os resultados podem ser usados como linhas orientadoras no desenvolvimento de produtos, ou seja, na seleção de materiais, na seleção de tecnologias de fabrico, no planeamento do destino final, na definição de estratégias, e em marketing.
Fundação para a Ciência e a Tecnologia (FCT) SFRH/BD/60852/2009 and the funding of Instituto de Polímeros e Compósitos (IPC) through strategic Project-LA 25-2011-2012 (PEsT-C(CTM/LA0025/2011). EU LIFE-environment programme project Ecovia (LIFE 05 ENV/P/00036).

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