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1.
Increasing the reaction temperature of the living cationic polymerization of isobutylene is crucial for industrial production due to the cost of refrigeration. The reaction temperature increase was achieved with an accelerated reaction rate using a flow reaction system. The polymerization conditions, including the flow reactor design, were based on the results of kinetic studies. Utilizing a milli‐scale flow reactor, polyisobutylene, which has a narrow molecular weight distribution, was obtained within a considerably short residence time at a high temperature. Furthermore, it was confirmed that the value of Mw/Mn correlates with the product of the Reynolds number and the angle of collision. 相似文献
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Information in a context-aware system has diverse natures. Raw data coming from sensors are aggregated and filtered to create more abstract information, which can be processed by context-aware application components to decide what actions should be performed. This process involves several activities: finding the available sources of information and their types, gathering the data from these sources, facilitating the fusion (aggregation and interpretation) of the different pieces of data, and updating the representation of the context to be used by applications. The reverse path also appears in context-aware systems, from changes in the context representation to trigger actions in certain actuators. FAERIE (Framework for AmI: Extensible Resources for Intelligent Environments) is a framework that facilitates management and fusion of context information at different levels. It is implemented as a distributed blackboard model. Each node of the system has a private blackboard to manage pieces of information that can be accessed by observer components, either locally or remotely (from other nodes) in a transparent way. The use of the framework is illustrated with a case study of an application for guiding people to meetings in a university building. 相似文献
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It has been known that contextual factors, such as atmospherics, can influence consumers’ perception of food and the overall consumption experience. This study aimed to investigate the influence of table linen on food perception. A total of 247 participants were provided meals with different table linens, either fabric or paper linen, in a real restaurant setting. The results demonstrated a fabric table linen contributed to a significant higher preference of the appetiser, first course consumed upon arrival, and of the meal quality in general. The fabric linen had no significant impact on the liking of the main dish and dessert, which were preferred similarly to that of paper table linen. However, a better service, ambiance and overall experience at the restaurant were attributed to the fabric table linen. Regarding the meal environmental elements, three quarters of the participants considered the table linen as an important element when they were eating at the restaurant. These results therefore demonstrate the importance of the table linen on consumers’ perception of food. 相似文献
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The execution context in which pervasive systems or mobile computing run changes continually. Hence, applications for these systems require support for self-adaptation to the continual context changes. Most of the approaches for self-adaptive systems implement a reconfiguration service that receives as input the list of all possible configurations and the plans to switch between them. In this paper we present an alternative approach for the automatic generation of application configurations and the reconfiguration plans at runtime. With our approach, the generated configurations are optimal as regards different criteria, such as functionality or resource consumption (e.g. battery or memory). This is achieved by: (1) modelling architectural variability at design-time using the Common Variability Language (CVL), and (2) using a genetic algorithm that finds nearly-optimal configurations at run-time using the information provided by the variability model. We also specify a case study and we use it to evaluate our approach, showing that it is efficient and suitable for devices with scarce resources. 相似文献
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Contextual knowledge is an essential resource for adapting business processes in order to keep them aligned with its goals. A context-based adaptation environment should learn from the dynamism of the context as well as the decisions made, and continuously identify new unforeseen situations. Data mining is a possibility to maintain the analysis of the processes updated. This paper presents a method that infers the need to learn new situations that influence a business process execution. The method is based on the results of the Apriori algorithm application. Case studies were conducted to evaluate the proposal. We observed evidences of context changes over time and the potential to learn with this dynamics through the method proposed. 相似文献
7.
Media as Educator,Media as Disruptor: Conceptualizing the Role of Social Context in Media Effects 下载免费PDF全文
We document how social contexts serve to refract media effects. We theorized the relationship between media use and individual‐level knowledge (and attitude) would be stronger when community‐level knowledge (and attitude) was low than when it was high. Data come from a national survey (N = 12,608 women and 1,237 men) conducted in Nepal. Knowledge and stigma toward people living with HIV were the 2 dependent variables. Hypotheses were tested 12 times: across the use of 3 media (newspaper, radio, television) × 2 study outcomes (knowledge and attitudes) × 2 genders. Predicted interactions were supported in 9 of the 12 tests. Findings point to the need to take into account the role of community factors in theorizing about media effects. 相似文献
8.
Alcoholic cocktails are consumed in very different situations and then consumers may differ in their favorite context to drink a cocktail. Diversity in the preferred context of cocktail consumption may reflect individual differences in taste responsiveness and personality traits as well as cocktail liking. This study aims at: 1) extending the efficacy of a coupled semiotic and statistical methodology for text analysis in uncovering aspects of preferred contexts of cocktail consumption; 2) testing if specific preferred contexts of cocktail consumption are related to individual differences; 3) investigating the relationships between preferred context to have cocktails and patterns of liking for cocktails. 159 cocktails consumers were characterized by personality traits, cocktail involvement, alcoholic beverages intake and PROP taster status and were asked to describe their preferred context to consume an alcoholic cocktail. Consumers were then asked to taste in blind conditions and rate their liking of six alcoholic aperitif cocktails. Three thematic clusters were identified (relax, sociability, aperitif). The relax lovers preferred a comforting context to have a cocktail; these consumers expressed a lower liking for the six evaluated samples than aperitif lovers but resulted more involved with cocktails as compared to the cluster sociability. This latter group of consumers focused on social aspects and novelty; they reported a higher intake of spirits than the cluster aperitif and showed higher scores in sensation seeking and disinhibition than the other clusters. The cluster aperitif described their favorite context as a “before dinner” situation; they were more involved with cocktails than the sociability cluster. Finally, the three clusters did not differ in PROP taster status distribution. The approach has proven to be useful to collect information and to segment consumers on the preferred aspects of cocktail experience. The study showed that consumer clusters with different preferred context for cocktail consumption differ in liking for the cocktails, personality traits, attitudes and alcohol intake. 相似文献
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After the “imported” urban forms, which originated from foreign cultures, were transplanted into Chinese cities, they generate brand-new urbanscape but suffer from a lack of cultural roots and a disconnection with the mainstream of contemporary urban planning. Thus, their current value and potential in urban renewal are questioned. The study takes the circular–radial space from the Baroque cities as an example to clarify the motivation of its import from the west to northeast China. It further clarifies their adaptive changes in form and function in the local urban context, through a case study on Dalian City. The study finds that different geometric patterns of existing circular–radial space were influenced by European, American, and Japanese urban planning theories to varying degrees, but with equal emphasis on symbolism and functionality. Their implementation in Dalian has a continuity in time and space. But due to the changes in topography, traffic, and planning concepts, their forms and functions tend to be independent, their connection weakens, and their importance recedes after the street network. The circular–radial space in Dalian led to distinctive urbanscape. But during their inheritance and transformation, the rationality of new forms and functions, as well as the necessity of continuing the initial ones need to be dialectically considered, so as to avoid dogmatic revival and antique reproduction. Finally, the study reconsiders the concept of “localization” of “imported” urban form, and constructs a general research pattern to provide a new perspective for understanding the transformation of similar types of urban forms. 相似文献
10.
Building performance – spanning energy use, greenhouse gas emissions, indoor environmental quality, etc. – is fundamental to the field of building engineering, yet it is typically taught with idealistic assumptions and traditional, teacher-centred, lecture-based methods. A promising emerging approach for university-level building engineering education is experiential learning, whereby students actively engage in complex tasks with real building data that reflect the kinds of problems graduates are likely to encounter in the workplace. To bridge the academic and employability skills and knowledge that they are developing through these tasks, students participate in reflective activities that help them to articulate the relevance and implications of the experience for lifelong learning. The objective of this paper is to assess the teaching and learning effectiveness of a data- and information-centric experiential learning approach to university-level engineering education. This paper reflects upon a particular course-based initiative informed by experiential learning theory that engaged fourth-year students in the life cycle of a new building on a university campus that was equipped with state-of-the-art building controls technologies. Students were provided access to a living lab resource with diverse artefacts from the building: drawings and building information models, guest lectures and technical tours, and live/historic data for the building. A series of assignments provided students with simulated problem scenarios to solve through the application of the building data as well as reflection prompts about their problem-solving process. The present paper details the assignments and the nature of the living lab data, students’ assignment results, and students and teaching assistants’ feedback on the overall teaching approach. The findings indicate a significant and continuous improvement in the reception and perceived educational value of the experiential assignments over the four-month term, suggesting living labs are a promising source of educational material for experiential learning. The paper concludes with lessons learned from the current course about experiential learning in building engineering education that can be applied more broadly to future courses in the field. 相似文献