• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 63
  • 42
  • 9
  • 8
  • 7
  • 3
  • 2
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • Tagged with
  • 169
  • 18
  • 13
  • 12
  • 12
  • 12
  • 11
  • 11
  • 10
  • 10
  • 10
  • 10
  • 10
  • 9
  • 9
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
51

Kunskap och innovation i ett moget kluster : En ekonomisk-geografisk studie av aluminiumindustrin i Småland-Blekinge / Knowledge and Innovation in a Mature Cluster : An Economic-Geographical Study of the Aluminium Product Cluster in Småland and Blekinge, Sweden

Lagerholm, Magnus January 2007 (has links)
The thesis aims at understanding mechanisms behind knowledge generation and learning in a mature cluster by analysing firms in south-east Sweden engaged in the development and manufacturing of aluminium products. The point of departure is in concepts and assumptions related to spatially concen-trated systems of similar and related firms and industries, such as agglomera-tions, clusters or innovation systems. Three sets of empirical analyses have been conducted: a mail survey, a series of in-depth interviews and a register-based analysis. The analyses focus on three themes: inter-firm relations, the embeddedness of the clustered firms in the region, and the role of labour and labour mobility in cluster development. It is shown that also in a rather mature and low-tech cluster, firm competi-tiveness rests on continuous knowledge upgrading and innovation. In general terms, firms in this cluster do have business relations with other firms at all different spatial scales. While there are manifold buyer-supplier relations within the cluster, most firms have their most important linkages outside the region. The firms regard themselves as part of a cluster and various mecha-nisms contribute to this. There is a strong sense of trust and loyalty, and this applies in particular to those engaged either in some of the more organized supplier networks or the regional cluster initiative Aluminiumriket. Finally, the cluster does not seem to constitute a very fluid labour market for special-ised skills. Labour mobility between firms in this particular cluster seems to be fairly low.
52

Analysis of Brand Recognition Associated with the Texas SuperstarTM and Earth-KindTM Programs in Texas

Collart Dinarte, Alba Jeanette. 2009 August 1900 (has links)
The environmental horticulture industry, also known as the “Green Industry”, is the second most important sector in the United States’ agricultural economy in terms of economic output and one of the fastest growing segments of agriculture; however, it has experienced a steady slowdown in growth in the past years. Floriculture and nursery crops average annual growth rate decreased from 13.64% in the 1970s to approximately 2.87% in the 2000s, and the industry is currently considered to be facing a mature market. The Texas A&M Agricultural Program, in an attempt to help Texas’ green industry producers compete effectively in an evolving marketplace, developed the Texas Superstar TM and Earth-Kind TM programs. Both of these programs intend to raise awareness among consumers of Texas-grown plant material while promoting environmental responsibility, and to increase producers’ profitability by providing them with products that can be sold at a price premium. In spite of the considerable investments on research and marketing that have been done in order to assure the release of every new plant, no research has investigated the effectiveness of these branding efforts in terms of consumer’s behavior. This research seeks to evaluate brand awareness and willingness-to-pay on the part of lawn and garden consumers. The discrete choice models used were the logit and probit model on brand awareness and the tobit model on the conditional willingness-to-pay. Results from this study conclude that consumers’ awareness of Texas Superstar TM and Earth-Kind TM in the Texas area is low, but the satisfaction level among aware consumers is high. The presence of awareness was found to increase willingness-to-pay for Texas Superstar TM and Earth-Kind TM by about 10%. Furthermore, profiles of the consumers’ behavioral and demographic characteristics that are more likely to influence brand awareness and willingness-to-pay were identified.
53

Optimization Of Mature Embryo Based Regeneration And Genetic Transformation Of Turkish Wheat Cultivars

Battal, Abdulhamit 01 September 2010 (has links) (PDF)
The objective of this study was to optimize tissue culture, transformation and regeneration parameters of mature embryo based culture of Triticum durum cv. Mirzabey 2000 and Triticum aestivum cv. Y&uuml / regir 89. The effects of auxin type of hormone at different concentrations and dark incubation periods on regeneration capacity were evaluated. Two different hormone types 2,4- dichlorophenoxyacetic acid and picloram were used at three different concentrations 2, 4 and 8 mg/l. Mature embryo derived calli were incubated in 6 different induction media at dark for 4 and 6 weeks for initiation of primary callus induction. After dark incubation periods, average callus fresh weight and primary callus induction rate were determined. The primary callus induction rates for 4 weeks and 6 weeks old dark adapted Mirzabey calli incubated was found to be 91 % and 93.25 % respectively. Y&uuml / regir primary callus induction rate was 92.5 % for 6 weeks old calli in 6W2D medium and 86.75 % for 4 weeks old calli in 4W8P medium. The primary calli were transferred to embryogenic callus induction medium. The embryogenic callus formation was 94.88 in 6W2D medium for Mirzabey cultivar. The necrosis was observed at high concentration of 2,4-D for both of cultivars. After embryogenic callus induction, embryogenic calli were transferred into hormone free regeneration medium. The maximum regeneration rate (62.31 %) and culture efficiency (44.13 %) were observed in 4W2D medium for Mirzabey. However, the low regeneration rate was observed for Y&uuml / regir (5 %) in 6W2D medium. The transformation studies were performed by using Obitek Biolab Gene Transfer System. The old and the modified loading units were used for optimization of bombardment pressure and distance for mature embryo based calli transformation. After bombardment of pAHC25 coated gold particles, histochemical GUS assay was performed and blue spots were counted. The transformation efficiency increased to 0.65 fold for 30 bar bombardment pressure and 5.5 fold for 35 bar bombardment by the modified loading unit. The modified loading unit could be used for further transformation studies.
54

Embryonic development and effects of environmental factors on the pre-mature hatchling of Sepia pharaonis

Lin, Chun-yen 10 September 2009 (has links)
Pre-mature hatching of fertilized eggs of cuttlefishes and squids, which are Taiwan¡¦s major fishing species, exists in the late embryonic development before yolk sacs are fully absorbed. It is so far unknown whether there is any difference in survival rate between pre-maturely developed juveniles and the fully developed ones. Hence, by laboratory incubation, this study aimed to discuss the relationship between the yolk size in the embryonic development process and embryo, as well as the difference in survival rate of juveniles developed at different developmental stages. The impact of the incubation time on the survival rate is explored in case of changing physical and chemical environmental factors (temperature, salinity, ammonia concentration, vibration etc.) The embryonic development of Sepia pharaonis can be divided into 40 stages according to the external shape and quality of the embryo. The embryo mantle length and the yolk diameter vary by time, while the increasing rate of the mantle length does not(F = 1.88, p = 0.06), increasing or decreasing in a linear relationship respectively. However, under the same environmental conditions, the consumption rate and the mantle size may vary in different batches(yolk diameter: F = 8.77, p < 0.01. mantle length: F = 92.14, p < 0.01). There is no difference in the surviving time of juveniles artificially and naturally incubated at the same developmental stage, and the surviving time will be longer if the artificially incubated juveniles are at later embryonic developmental stages(F = 34.66¡Ap < 0.01). With regard to the feeding ratio of juveniles pre-maturely hatched at different stages, the feeding ratio of the juveniles incubated after the 36th stage will increase with the developmental stages(F = 93.10¡Ap < 0.01). In this study, the temperature limit of the embryonic development of Sepia pharaonis should never be lower than 10¢J or higher than 35¢J, and the most suitable temperate range is between 17-28¢J. In case of sudden change in temperature, temperature increase can more effectively affect the pre-mature hatching than temperature decrease. In case of either the 36th or 39th stage embryos, if the temperature rises or drops by more than 10 degrees, pre-mature hatching can exist in some of the embryos. Some embryos may die if salinity is lowered suddenly below 20 psu. Meanwhile, pre-mature hatching may occur within one hour if it is suddenly lowered below 10 psu, and the unhatched embryos may die. When increasing the ammonia concentration suddenly to 1 and 5 ppm, the embryo incubation time may be lengthened compared with the group without the addition: some embryos may die if it is increased to 5 ppm. Meanwhile, most embryos are hatched pre-maturely within 17 minutes when it is increased to 1000 ppm, while those unhatched ones may die. In case of various environmental stimuli of the experiments, a higher percentage of embryos at the 39th stage got away from the hostile environment by pre-mature hatching, while a higher percentage of embryos at 36th stage continued the development until natural incubation or died. The vibration experiment is to produce vibration by a vertical vibration instrument. In case of 30-minute vibration at frequency of 350 times/minute and maximum amplitude at 2 cm, there is no effect on incubation time and mode of embryos at both stages. This factor is still open and subject to further discussion.
55

Brandžių medynų inventorizacijos miškotvarkos metu patikimumo įvertinimas / Reliability of growing stock volume estimation of mature stands during standwise forest inventory

Krygeris, Erikas 15 June 2009 (has links)
Magistro darbe tiriama brandžių medynų inventorizacijos miškotvarkos metu patikimumas. Darbo objektas – Kazlų Rūdos mokomosios miškų urėdijos valstybinės reikšmės miškų II-IV miškų grupės brandūs medynai. Darbo tikslas – išanalizuoti brandžių medynų inventorizacijos miškotvarkos metu tikslumą ir įvertinti atrankinės miškų inventorizacijos efektyvumą. Darbo metodai – Palyginamoji analizė, atrankos metodas. Darbo rezultatai - Brandžių medynų visuma inventorizuota atrankos metodu. Pagrindinis šio metodo pranašumas – jo objektyvumas, leidžiantis patikimai su žinoma atrankos paklaida įvertinti inventorizuotų medynų vidutinius rodiklius, pirmoje eilėje vidutinį tūrį. Tokiu būdu nustatytas brandžių medynų tūris yra 12 % didesnis už sklypinės inventorizacijos metu nustatytą tūrį, panaudojant taip pat atrankos metodą kiekviename sklype. Brandžių medynų visumos atrankinės inventorizacijos metu nustatytas medžių tūrio kintamumas, leisiantis geriau planuoti tokias inventorizacijas. Didžiausiu vidutinio medžių tūrio kintamumu Kazlų Rūdos miškų urėdijoje pasižymi brandūs pušynai (variacijos koeficientas – 48%). Beržynų ir eglynų tūrio variacijos koeficientas 40-41%, juodalksnynų - 37%. / The work object is Kazlų Rūda forest enterprises, II-IV group mature stands. The main goal of the work was to estimate the reliability of inventory mature stands during standwise inventory. Methods. Comparative analysis and sampling methods were used. The main results Mature stands were inventoried by sampling method. The main advantage of this method - its objectivity, which allow to estimate growing stock volume of mature stands with known error. Estimated mature stands volume of growing stock is 12 % higher than volume inventoried using angle count inventory method for each individual compartment. Estimated variation of growing stock of volume mature stands will allow to calculate other inventories. The highest variation of growing stock volume of mature stands Kazlų Rūda forest enterprise is in pine stands– 48 % medium, in birch and spruce stands 40-41 %, and the least in black alder stands– 37 %.
56

Kriptogamų įvairovė skirtingo miškų ūkinės veiklos intensyvumo senuose plačialapių ir mišriuose su plačialapiais medžiais miškuose / Cryptogam diversity in old broadleaved and mixed with broadleaves forests of different forest management intensity

Preikša, Žydrūnas 18 October 2011 (has links)
Darbo tikslas yra ištirti kriptogamų rūšių įvairovės dėsningumus skirtingo miškų ūkinės veiklos intensyvumo senuose plačialapių ir mišriuose su plačialapiais medžiais miškuose. Tikslui pasiekti buvo iškelti šie darbo uždaviniai: 1. Nustatyti indikatorinių kriptogamų rūšių skaičių ir gausą skirtingo miškų ūkinės veiklos intensyvumo brandžiuose medynuose; 2. Nustatyti pagrindinius veiksnius, turinčius įtaką indikatorinių kriptogamų rūšių skaičiui ir gausai. 3. Įvertinti skirtingo miškų ūkinės veiklos intensyvumo įtaką indikatorinių kriptogamų rūšių skaičiui ir gausai. 4. Įvertinti indikatorinių kriptogamų rūšių grupes pagal jų augimo vietą ir aplinkos sąlygas. / The objective was to investigate regularities of diversity of cryptogam species in old broadleaved and mixed forests of different forest management intensity. The research was based on the following hypothesis: cryptogam species richness and abundance in a pristine forest are at least twice bigger than in a commercial forest; even extensive forest cutting has a long-term negative impact on rare cryptogam species; coarse dead wood is an extremely important substratum which maintains high cryptogam diversity in the forest; coarse dead wood is more important than the fine one for rare species survival; decayed dead wood is vital for some rare species survival; multispecied stand increases diversity of substrata and creates favourable conditions for higher number of species. To achieve the objective, the following tasks were set up: 1. To evaluate number and abundance of indicator species of cryptogams in mature stands with different intensity of forest management; 2. To determine main factors, influencing number and abundance of indicator species of cryptogams; 3. To evaluate impact of different intensity of forest management on the number and abundance of indicator species of cryptogams; 4. To evaluate groups of indicator species of cryptogams according to their growing place and environmental conditions.
57

Business Model Innovation in Incumbent Organizations: : Challenges and Success Routes

Salama, Ahmad, Parvez, Khawar January 2015 (has links)
In this thesis major challenges of creating business models at incumbents within mature industries are identified along with a mitigation plan. Pressure is upon incumbent organizations in order to keep up with the latest rapid technological advancements, the launching of startups that almost cover every field of business and the continuous change in customers’ tastes and needs. That along with various factors either forced organizations to continually reevaluate their current business models or miss out on great opportunities. How some incumbents have dealt and are dealing with business model innovation challenges over the past few years is demonstrated through several cases of incumbents. The sources surveyed include recent scientific articles, books, firsthand accounts with executives in the area of business models, innovation and business development, online sources and contemporary business publications. In order to overcome those challenges, we propose a framework which is derived mainly from the sources mentioned above. In order to overcome such challenges, thesis propose a framework that can be used to successfully engender new business models and make a transition from current to new business model. By successful business model innovation, firms can increase the extent of their offerings, meet yet unmet market demands and untapped customer segments. Additionally, organizations can create new value propositions and gain highly sustainable competitive position through business model innovation which is not easy to imitate or copy by the competition. Our findings attest to the fact that business models are highly situational however there are general steps for incumbent organizations that would lead to a successful business model innovation approach. First an organization must have a clear strategy. Establishing separate innovation centers for firms do enhance and foster the mindset of innovation as they take innovation outside the parent organization’s logic. Other approaches include open innovation, partnerships and ensuring that resources are constantly allocated to create disruptive innovations internally and is led by the right personalities. Solving customer needs should be the core of any business and finally there are no best practices in business model innovation. The significance of our findings gives insights on how to overcome some challenges in practice for incumbents to create suitable business models and contributes to theory since there were some empirical findings that weren’t pronounced in literature.
58

Business Model Innovation in Incumbent Organizations: Challenges and Success Routes

Parvez, Khawar, Salama, Ahmad January 2015 (has links)
In this thesis major challenges of creating business models at incumbents within mature industries are identified along with a mitigation plan. Pressure is upon incumbent organizations in order to keep up with the latest rapid technological advancements, the launching of startups that almost cover every field of business and the continuous change in customers’ tastes and needs. That along with various factors either forced organizations to continually reevaluate their current business models or miss out on great opportunities.How some incumbents have dealt and are dealing with business model innovation challenges over the past few years is demonstrated through several cases of incumbents. The sources surveyed include recent scientific articles, books, firsthand accounts with executives in the area of business models, innovation and business development, online sources and contemporary business publications. In order to overcome those challenges, we propose a framework which is derived mainly from the sources mentioned above.In order to overcome such challenges, thesis propose a framework that can be used to successfully engender new business models and make a transition from current to new business model. By successful business model innovation, firms can increase the extent of their offerings, meet yet unmet market demands and untapped customer segments. Additionally, organizations can create new value propositions and gain highly sustainable competitive position through business model innovation which is not easy to imitate or copy by the competition.Our findings attest to the fact that business models are highly situational however there are general steps for incumbent organizations that would lead to a successful business model innovation approach. First an organization must have a clear strategy. Establishing separate innovation centers for firms do enhance and foster the mindset of innovation as they take innovation outside the parent organization’s logic. Other approaches include open innovation, partnerships and ensuring that resources are constantly allocated to create disruptive innovations internally and is led by the right personalities. Solving customer needs should be the core of any business and finally there are no best practices in business model innovation. The significance of our findings gives insights on how to overcome some challenges in practice for incumbents to create suitable business models and contributes to theory since there were some empirical findings that weren’t pronounced in literature.
59

The Effects Of Thidiazuron On Callus Development And Organogenesis From Mature Embryos Of Selected Turkish Bread And Durum Wheat Varieties

Yaqubov, Nihad 01 July 2004 (has links) (PDF)
The effects of cytokinin-like Thidiazuron growth regulator on the regeneration responses of callus cultures of Turkish bread Triticum aestivum L. cv. (BaSak 95, Gerek 79, and Bezostaja 1) and durum Triticum durum Desf. cv. (Kunduru, &Ccedil / akmak 79, and Kirmizi 5132) wheat varieties have been investigated in this study. High callus induction frequencies are found to be independent of bread and durum wheat varieties ( &rsaquo / 96%) whereas the callus weight is found to be variety-dependent. For bread wheat, BaSak 95 and for the durum wheat Kunduru is found to be the best performers. TDZ treatments are found to be negatively affecting the regeneration capacity of all the tested bread wheat varieties whereas for the durum wheat variety of Kunduru positive effect is observed. Since the culture efficiency is a derivation from the regeneration capacity, this parameter yielded very similar results as in the case of regeneration capacity for both bread and durum wheat varieties. In bread wheat varieties, the TDZ treatments increased the number of regenerated plants more than 2-fold when compared with the control and likewise very similar results were obtained from durum wheat varieties. Unfortunately, following their transfer to soil, plants that were treated with various concentrations of TDZ displayed reduced vigor probably due to underdeveloped roots. In addition, majority of these plants did not sufficiently develop above the ground parts when compared with the control plants. The simplicity and rapid development of shoots using mature embryos could potentially be used for regenerating superior plants following gene transfer studies in the future.
60

A Hierarchical Multiscale Approach to History Matching and Optimization for Reservoir Management in Mature Fields

Park, Han-Young 2012 August 1900 (has links)
Reservoir management typically focuses on maximizing oil and gas recovery from a reservoir based on facts and information while minimizing capital and operating investments. Modern reservoir management uses history-matched simulation model to predict the range of recovery or to provide the economic assessment of different field development strategies. Geological models are becoming increasingly complex and more detailed with several hundred thousand to million cells, which include large sets of subsurface uncertainties. Current issues associated with history matching, therefore, involve extensive computation (flow simulations) time, preserving geologic realism, and non-uniqueness problem. Many of recent rate optimization methods utilize constrained optimization techniques, often making them inaccessible for field reservoir management. Field-scale rate optimization problems involve highly complex reservoir models, production and facilities constraints and a large number of unknowns. We present a hierarchical multiscale calibration approach using global and local updates in coarse and fine grid. We incorporate a multiscale framework into hierarchical updates: global and local updates. In global update we calibrate large-scale parameters to match global field-level energy (pressure), which is followed by local update where we match well-by-well performances by calibration of local cell properties. The inclusion of multiscale calibration, integrating production data in coarse grid and successively finer grids sequentially, is critical for history matching high-resolution geologic models through significant reduction in simulation time. For rate optimization, we develop a hierarchical analytical method using streamline-assisted flood efficiency maps. The proposed approach avoids use of complex optimization tools; rather we emphasize the visual and the intuitive appeal of streamline method and utilize analytic solutions derived from relationship between streamline time of flight and flow rates. The proposed approach is analytic, easy to implement and well-suited for large-scale field applications. Finally, we present a hierarchical Pareto-based approach to history matching under conflicting information. In this work we focus on multiobjective optimization problem, particularly conflicting multiple objectives during history matching of reservoir performances. We incorporate Pareto-based multiobjective evolutionary algorithm and Grid Connectivity-based Transformation (GCT) to account for history matching with conflicting information. The power and effectiveness of our approaches have been demonstrated using both synthetic and real field cases.

Page generated in 0.8725 seconds