922 resultados para Horizontal and Vertical Product Differentiation


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The present study examined how personality and social psychological factors affect third and fourth graders' computer-mediated communication. Personality was analysed in terms of the following strategies: optimism, pessimism and defensive pessimism. Students worked either individually or in dyads which were paired homogeneously or heterogeneously according to the strategies. Moreover, the present study compared horizontal and vertical interaction. The study also examined the role that popularity plays, and students were divided into groups based on their popularity level. The results show that an optimistic strategy is useful. Optimism was found to be related to the active production and processing of ideas. Although previous research has identified drawbacks to pessimism in achievement settings, this study shows that the pessimistic strategy is not as debilitating a strategy as is usually assumed. Pessimistic students were able to process their ideas. However, defensive pessimists were somewhat cautious in introducing or changing ideas. Heterogeneous dyads were not beneficial configurations with respect to producing, introducing, or changing ideas. Moreover, many differences were found to exist between the horizontal and vertical interaction; specifically, the students expressed more opinions and feelings when teachers took no part in the discussions. Strong emotions were observed especially in the horizontal interaction. Further, group working skills were found to be more important for boys than for girls, while rejected students were not at a disadvantage compared to popular ones. Schools can encourage emotional and social learning. The present study shows that students can use computers to express their feelings. In addition, students who are unpopular in non-computer contexts or students who use pessimism can benefit from computers. Participation in computer discussions can give unpopular children a chance to develop confidence when relating to peers.

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Isolated nuclei from differentiating cultures of Nicotiana sanderae showed increased levels of RNA polymerase activity as compared to the nuclei from callus cultures. The RNA synthetic activity was dependent on nucleotide triphosphates and Mg2+ and was destroyed by RNase. Maximum activity was obtained in the presence of 50 mM (NH4)2 SO4 and α-amanitin inhibited 40% and 55% of the activity in the nuclei from callus and differentiating tissue respectively. The nuclei from differentiating tissue elicited a 3-fold increase in RNA polymerase I and a 4-fold augmentation in RNA polymerase II activities.

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The influence of atmospheric aerosols on Earth's radiation budget and hence climate, though well recognized and extensively investigated in recent years, remains largely uncertain mainly because of the large spatio-temporal heterogeneity and the lack of data with adequate resolution. To characterize this diversity, a major multi-platform field campaign ICARB (Integrated Campaign for Aerosols, gases and Radiation Budget) was carried out during the pre-monsoon period of 2006 over the Indian landmass and surrounding oceans, which was the biggest such campaign ever conducted over this region. Based on the extensive and concurrent measurements of the optical and physical properties of atmospheric aerosols during ICARB, the spatial distribution of aerosol radiative forcing was estimated over the entire Bay of Bengal (BoB), northern Indian Ocean and Arabian Sea (AS) as well as large spatial variations within these regions. Besides being considerably lower than the mean values reported earlier for this region, our studies have revealed large differences in the forcing components between the BoB and the AS. While the regionally averaged aerosol-induced atmospheric forcing efficiency was 31 +/- 6 W m(-2) tau(-1) for the BoB, it was only similar to 18 +/- 7 W m(-2) tau(-1) for the AS. Airborne measurements revealed the presence of strong, elevated aerosol layers even over the oceans, leading to vertical structures in the atmospheric forcing, resulting in significant warming in the lower troposphere. These observations suggest serious climate implications and raise issues ranging from the impact of aerosols on vertical thermal structure of the atmospheric and hence cloud formation processes to monsoon circulation.

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The modern food system and sustainable development form a conceptual combination that suggests sustainability deficits in environmental impacts and nutritional status of western populations. This study explores actors orientations towards sustainability by probing into social dynamics for sustainability within primary production and public consumption. If actors within these two worlds were to express converging orientations for sustainability, the system dynamics of the market would enable more sustainable growth in terms of production dictated by consumption. The study is based on a constructivist research approach with qualitative text analyses. The findings were validated by internal and external food system actors and are suggested to represent current social dynamics within Finnish food system. The key findings included primary producers social skilfulness, which enabled networking with other actors in very different paths of life, learning in order to promote one s trade, and trusting reflectively in partners in order to expand business. These activities extended the supply chain in a spiral fashion by horizontal and vertical forward integration, until large retailers were met for negotiations on a more equal basis. This mode of chain level coordination, typically building around the core of social and partnership relations, was coined as a socially overlaid network, and seen as sustainable coordination mode for endogenous growth. The caterers exhibited more or less committed professional identity for sustainability within their reach. The facilitating approaches for professional identities dealt successfully with local and organic food in addition to domestic food, and also imported food. The co-operation with supply chains created innovative solutions and savings for the business parties to be shared. There were also more complicated identities as juggling, critical and delimited approaches for sustainability, with less productive efforts due to restrictions such as absence of organisational sustainability strategy, weak presence of local and organic suppliers, limited understanding about sustainability and no organisational resources for informed choices for sustainability. The convergence between producers and caterers existed to an extent allowing suggestion that increased clarity about sustainable consumption and production by actors could be constructed using advanced tools. The study looks for introduction of more profound environmental and socio-economic knowledge through participatory research with supply chain actors. Learning in the workplace about food system reality in terms of supply chain co-operation may prove to be a change engine that leads to advanced network operations and a more sustainable food system.

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Abstract The modern food system and sustainable development form a conceptual combination that suggests sustainability deficits in the ways we deal with food consumption and production - in terms of economic relations, environmental impacts and nutritional status of western population. This study explores actors’ orientations towards sustainability by taking into account actors’ embedded positions within structures of the food system, actors’ economic relations and views about sustainability as well as their possibilities for progressive activities. The study looks particularly at social dynamics for sustainability within primary production and public consumption. If actors within these two worlds were to express converging orientations for sustainability, the system dynamics of the market would enable more sustainable growth in terms of production dictated by consumption. The study is based on a constructivist research approach with qualitative text analyses. The data consisted of three text corpora, the ‘local food corpus’, the ‘catering corpus’ and the ‘mixed corpus’. The local food actors were interviewed about their economic exchange relations. The caterers’ interviews dealt with their professional identity for sustainability. Finally, the mixed corpus assembled a dialogue as a participatory research approach, which was applied in order to enable researcher and caterer learning about the use of organic milk in public catering. The data were analysed for theoretically conceptualised relations, expressing behavioural patterns in actors’ everyday work as interpreted by the researcher. The findings were corroborated by the internal and external communities of food system actors. The interpretations have some validity, although they only present abstractions of everyday life and its rich, even opaque, fabric of meanings and aims. The key findings included primary producers’ social skilfulness, which enabled networking with other actors in very different paths of life, learning in order to promote one’s trade, and trusting reflectively in partners in order to extend business. These activities expanded the supply chain in a spiral fashion by horizontal and vertical forward integration, until large retailers were met for negotiations on a more equal or ‘other regarding’ basis. This kind of chain level coordination, typically building around the core of social and partnership relations, was coined as a socially overlaid network. It supported market access of local farmers, rooted in their farms, who were able to draw on local capital and labour in promotion of competitive business; the growth was endogenous. These kinds of chains – one conventional and one organic – were different from the strategic chain, which was more profit based and while highly competitive, presented exogenous growth as it depended on imported capital and local employees. However, the strategic chain offered learning opportunities and support for the local economy. The caterers exhibited more or less committed professional identity for sustainability within their reach. The facilitating and balanced approaches for professional identities dealt successfully with local and organic food in addition to domestic food, and also imported food. The co-operation with supply chains created innovative solutions and savings for the business parties to be shared. The rule-abiding approach for sustainability only made choices among organic supply chains without extending into co-operation with actors. There were also more complicated and troubled identities as juggling, critical and delimited approaches for sustainability, with less productive efforts due to restrictions such as absence of organisational sustainability strategy, weak presence of local and organic suppliers, limited understanding about sustainability and no organisational resources to develop changes towards a sustainable food system. Learning in the workplace about food system reality in terms of supply chain co-operation may prove to be a change engine that leads to advanced network operations and a more sustainable food system. The convergence between primary producers and caterers existed to an extent allowing suggestion that increased clarity about sustainable consumption and production by actors could be approached using advanced tools. The study looks for introduction of more profound environmental and socio-economic knowledge through participatory research with supply chain actors in order to promote more sustainable food systems. Summary of original publications and the authors’ contribution I Mikkola, M. & Seppänen, L. 2006. Farmers’ new participation in food chains: making horizontal and vertical progress by networking. In: Langeveld, H. & Röling N. (Eds.). Changing European farming systems for a better future. New visions for rural areas. Wageningen, The Netherlands. Wageningen Academic Publishers: 267–271. II Mikkola, M. 2008. Coordinative structures and development of food supply chains. British Food Journal 110 (2): 189–205. III Mikkola, M. 2009. Shaping professional identity for sustainability. Evidence in Finnish public catering. Appetite 53 (1): 56–65. IV Mikkola, M. 2009. Catering for sustainability: building a dialogue on organic milk. Agronomy Research 7 (Special issue 2): 668–676. Minna Mikkola has been responsible for developing the generic research frame, particular research questions, the planning and collection of the data, their qualitative analysis and writing the articles I, II, III and IV. Dr Laura Seppänen has contributed to the development of the generic research frame and article I by introducing the author to the basic concepts of economic sociology and by supporting the writing of article II with her critical comments. Articles are printed with permission from the publishers.

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The research question of this thesis was how knowledge can be managed with information systems. Information systems can support but not replace knowledge management. Systems can mainly store epistemic organisational knowledge included in content, and process data and information. Certain value can be achieved by adding communication technology to systems. All communication, however, can not be managed. A new layer between communication and manageable information was named as knowformation. Knowledge management literature was surveyed, together with information species from philosophy, physics, communication theory, and information system science. Positivism, post-positivism, and critical theory were studied, but knowformation in extended organisational memory seemed to be socially constructed. A memory management model of an extended enterprise (M3.exe) and knowformation concept were findings from iterative case studies, covering data, information and knowledge management systems. The cases varied from groups towards extended organisation. Systems were investigated, and administrators, users (knowledge workers) and managers interviewed. The model building required alternative sets of data, information and knowledge, instead of using the traditional pyramid. Also the explicit-tacit dichotomy was reconsidered. As human knowledge is the final aim of all data and information in the systems, the distinction between management of information vs. management of people was harmonised. Information systems were classified as the core of organisational memory. The content of the systems is in practice between communication and presentation. Firstly, the epistemic criterion of knowledge is not required neither in the knowledge management literature, nor from the content of the systems. Secondly, systems deal mostly with containers, and the knowledge management literature with applied knowledge. Also the construction of reality based on the system content and communication supports the knowformation concept. Knowformation belongs to memory management model of an extended enterprise (M3.exe) that is divided into horizontal and vertical key dimensions. Vertically, processes deal with content that can be managed, whereas communication can be supported, mainly by infrastructure. Horizontally, the right hand side of the model contains systems, and the left hand side content, which should be independent from each other. A strategy based on the model was defined.

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The study of soil microbiota and their activities is central to the understanding of many ecosystem processes such as decomposition and nutrient cycling. The collection of microbiological data from soils generally involves several sequential steps of sampling, pretreatment and laboratory measurements. The reliability of results is dependent on reliable methods in every step. The aim of this thesis was to critically evaluate some central methods and procedures used in soil microbiological studies in order to increase our understanding of the factors that affect the measurement results and to provide guidance and new approaches for the design of experiments. The thesis focuses on four major themes: 1) soil microbiological heterogeneity and sampling, 2) storage of soil samples, 3) DNA extraction from soil, and 4) quantification of specific microbial groups by the most-probable-number (MPN) procedure. Soil heterogeneity and sampling are discussed as a single theme because knowledge on spatial (horizontal and vertical) and temporal variation is crucial when designing sampling procedures. Comparison of adjacent forest, meadow and cropped field plots showed that land use has a strong impact on the degree of horizontal variation of soil enzyme activities and bacterial community structure. However, regardless of the land use, the variation of microbiological characteristics appeared not to have predictable spatial structure at 0.5-10 m. Temporal and soil depth-related patterns were studied in relation to plant growth in cropped soil. The results showed that most enzyme activities and microbial biomass have a clear decreasing trend in the top 40 cm soil profile and a temporal pattern during the growing season. A new procedure for sampling of soil microbiological characteristics based on stratified sampling and pre-characterisation of samples was developed. A practical example demonstrated the potential of the new procedure to reduce the analysis efforts involved in laborious microbiological measurements without loss of precision. The investigation of storage of soil samples revealed that freezing (-20 °C) of small sample aliquots retains the activity of hydrolytic enzymes and the structure of the bacterial community in different soil matrices relatively well whereas air-drying cannot be recommended as a storage method for soil microbiological properties due to large reductions in activity. Freezing below -70 °C was the preferred method of storage for samples with high organic matter content. Comparison of different direct DNA extraction methods showed that the cell lysis treatment has a strong impact on the molecular size of DNA obtained and on the bacterial community structure detected. An improved MPN method for the enumeration of soil naphthalene degraders was introduced as an alternative to more complex MPN protocols or the DNA-based quantification approach. The main advantage of the new method is the simple protocol and the possibility to analyse a large number of samples and replicates simultaneously.

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UTT (Ultrasonic Tomography Tool) is widely used in the oil industry and can be used to inspect corrosion, casing wall damage, casing breakoff, and casing distortion in the well borehole with the maximum environment temperature being 125 °C, and the pressure being 60 MPa. UTT consists of tool head, upper centralization, electronic section, lower centralization, transmitters, and receivers. Its outer diameter is 4.6 cm and length is 320 cm. The measured casing diameter ranges from 60 mm to 254 mm. The tomography resolution is 512×512. The borehole measurement accuracy is 2 mm. It can supply 3D pipe tomography, including horizontal and vertical profile. This paper introduces its specification, measurement principle, and applications in oilfield.damage, casing breakoff, and casing distortion in the well borehole with the maximum environment temperature being 125 °C, and the pressure being 60 MPa. UTT consists of tool head, upper centralization, electronic section, lower centralization, transmitters, and receivers. Its outer diameter is 4.6 cm and length is 320 cm. The measured casing diameter ranges from 60 mm to 254 mm. The tomography resolution is 512×512. The borehole measurement accuracy is 2 mm. It can supply 3D pipe tomography, including horizontal and vertical profile. This paper introduces its specification, measurement principle, and applications in oilfield.

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The self-assembling process near the three-phase contact line of air, water and vertical substrate is widely used to produce various kinds of nanostructured materials and devices. We perform an in-situ observation on the self-assembling process in the vicinity of the three phase contact line. Three kinds of aggregations, i.e. particle-particle aggregation, particle-chain aggregation and chain-chain aggregation, in the initial stage of vertical deposition process are revealed by our experiments. It is found that the particle particle aggregation and the particle-chain aggregation can be qualitatively explained by the theory of the capillary immersion force and mirror image force, while the chain-chain aggregation leaves an opening question for the further studies. The present study may provide more deep insight into the self-assembling process of colloidal particles.

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The probability distribution of lift-off velocity of the saltating grains is a bridge to linking microscopic and macroscopic research of aeolian sand transport. The lift-off parameters of saltating grains (i.e., the horizontal and vertical lift-off velocities, resultant lift-off velocity, and lift-off angle) in a wind tunnel are measured by using a Phase Doppler Particle Analyzer (PDPA). The experimental results show that the probability distribution of horizontal lift-off velocity of saltating particles on a bed surface is a normal function, and that of vertical lift-off velocity is an exponential function. The probability distribution of resultant lift-off velocity of saltating grains can be expressed as a log-normal function, and that of lift-off angle complies with an exponential function. A numerical model for the vertical distribution of aeolian mass flux based on the probability distribution of lift-off velocity is established. The simulation gives a sand mass flux distribution which is consistent with the field data of Namikas (Namikas, S.L., 2003. Field measurement and numerical modelling of acolian mass flux distributions on a sandy beach, Sedimentology 50, 303-326). Therefore, these findings are helpful to further understand the probability characteristics of lift-off grains in aeolian sand transport. (c) 2007 Elsevier B.V. All rights reserved.