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Critical information systems (IS) research, it is argued, does not have a distinct methodological identity. While some research methods are closely related to the positivist research paradigm (experiments, surveys, and structural equation modelling) and others to the interpretivist paradigm (field study, ethnography, and action research), the critical paradigm is not identified with specific ‘critical methods’ and typically relies on the appropriation of interpretivist methods (such as critical ethnography). The criticism of the critical research paradigm in IS has often focused on the lack of distinctly critical research methods and even the neglect of methodological issues (Klein; McGrath). This paper questions the notion of and the arguments behind the quest for ‘critical research methods’ defined in contrast to positivist and interpretivist methods. Instead, the paper argues that it is a critical research methodology – understood as an overall strategy of conceptualizing and conducting an inquiry, engaging with studied phenomena, and constructing and justifying socially relevant knowledge, which distinguishes critical from other research paradigms. Building on a Kleinian argument regarding the need for common principles across diverse critical IS inquiries (Klein; Myers & Klein) this paper proposes a framework that describes key dimensions of a critical research methodology that distinguish critical from other research paradigms and provide methodological guidance in the doing of critical research.  相似文献   
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Government agencies worldwide continue their commitment to providing open data in order to increase transparency of education, healthcare and other public services. Focusing on open government information systems (IS) that provide performance-related data, this paper explores the ongoing tension between government’s goal of transparency and the resulting largely opaque datification effects. Our research insights are derived from an empirical longitudinal study of a controversial open government IS called My School, currently providing performance data on almost 10,000 schools in Australia. We investigate the tension between transparency intended with schools’ open performance data and datification effects they create within the education system and a broader society, through the theoretical lens of Complex Adaptive Systems (CAS). Our study reveals how the tension emerges due to unpredictable use, propagation and reinterpretation of open data by more and more users. Consequently, the original meaning of data gets distorted, as these users continue to reconstruct and reinterpret ‘data’ in their own contexts and adapt their behavior in pursuit of their strategic goals. We also identify and theorize seven datification patterns underlying the tension and the ways they produce various social consequences. Based on these research contributions we discuss important strategic implications for government decision makers and identify new opportunities for future research on open government IS.  相似文献   
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The igniter consisting of 34% Mg, 60% KNO3, 3% KClO4 and 3% organic binder was subjected to accelerated aging under the conditions of 85% relative humidity at 65°C, 75°C and 85°C, and at 75°C with 92% relative humidity. Chemical aging was followed through formation of Mg(OH)2 and KNO2. Functional characterization was accomplished in a device constructed to enable simultaneous determination of the heat of combustion and pressure-time recording of the combustion process of both fresh and aged samples. The maximum acceptable deterioration occured at different times depending upon the conditions. The acceleration factor for every 10°C at 85% relative humidity is on average 2.8, leading to a prediction of shelf life of not more than 4 years at 25°C. At the time when burning characteristics were significantly changed, the mixture suffered only slight chemical changes, with only about 1% Mg(OH)2 and 0.5% KNO2 being formed. Thus, no chemical changes should be tolerated in such formulations.  相似文献   
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The paper presents a numerical model of transient, saturated-unsaturated water flow through a porous medium. The model solves Richards' equation, which is assumed to present water flow in both unsaturated and saturated zones. The equation is solved by the implicit iterative finite difference method, using the over-relaxation technique. The model is tested by comparison with published laboratory experiments. The agreement between measured and computed values is very good for both infiltration and drainage experiments. The purpose of the model is the prediction of a soil-water regime either in natural conditions or under the influence of an irrigation or drainage system.  相似文献   
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Abstract.  This paper presents the findings of a longitudinal study of the Slovenian company Sava during its 1995–2004 transition period when it adapted to and prospered in a free market economy. The company is particularly interesting because of its successful transition from a socialist company operating in a protected market to a privatized company operating in a capitalist global market, as well as the pivotal role of information technology (IT)-supported organizational learning that brought about radical change and successful transition. Our investigation of Sava's experiences demonstrates how the company's increasing attention to organizational learning, integration of working and learning, and its constant innovation of products and processes created new needs for IT support that motivated the adoption of new IT systems (such as Lotus Notes, document management systems, SAP), which in turn increased Sava's capacity to learn. Furthermore, our study reveals how the role of IT systems in organizational learning depends on the nature of learning (single-loop, double-loop or triple-loop learning) and the organizational level at which learning takes place (individual, group/department or organization). By providing insight into the emergence of distinct types of IT-supported learning and their vital role in Sava's successful transition, the paper contributes to a deeper understanding of the relationship between IT and organizational learning that is relevant and inspiring to other companies, especially those operating in transition economies.  相似文献   
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We offered a new perspective on communication in computer-mediated environments by examining communicative practices used during discussion in an online financial forum about a listed company that was experiencing abnormal trading behavior. The analysis of communicative practices showed how the linguistic nature of the online forum allowed covert manipulation of inexperienced and unsuspecting forum participants - against all the norms and rules governing online financial forums. Based on our theoretical understanding of communicative practices, we found a discrepancy between the expectations of and the actual divergence from an ideal communicative environment free from distortion and manipulation that is normally assumed to govern online forums. The discrepancy, which remains largely concealed, can be seen as a major factor in the negative implications of online financial forums.  相似文献   
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This paper presents the calculation of the power of solar rays that pass through the window of an observed room and their impact on warming up and lighting of the room. The calculations were performed using a mathematical model that takes into account the geographical position of the object, time zone, orientation of windows, day of the year, and current time. This paper also includes the calculation of geometry of the solar radiation and its intensity, artificial light and cooling/heating demands. Based on data from above, the optimization of blind tilt angle was performed to achieve the best possible brightness of the room and energy savings when heating or cooling, depending on ambient temperature. Optimization was performed using a genetic algorithm and fuzzy logic. After an analysis of the results obtained from optimization of the blind tilt angle, an algorithm for blinds control was developed in order to achieve energy savings and comfort in the observed room. Based on the derived conclusions, an UML diagram was made that describes the algorithm for determining optimal blind tilt angle.  相似文献   
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Dubravka Hršak 《Water research》1996,30(12):3092-3098
Cometabolic transformation of commercial linear alkylbenzenesulphonates (LAS) and pure congeners of 2-[4-(sulphophenyl)]nonan (2C9LAS) and 2-[4-(sulphophenyl)]decan (2C10LAS) was studied by using a mixed methanotrophic-heterotrophic culture MM1 and a pure culture of type II methanotroph (strain CSC1), isolated from culture MM1. Cultures were grown in shake flasks under conditions promoting expression of the soluble methane monooxygenase (sMMO). Both the mixed culture MM1 and the pure culture CSC1 were capable of transforming LAS with or without methane as the natural substrate. Experiments performed without methane (resting cells) showed faster cometabolic transformation of LAS congeners with longer alkyl side-chains. Both 2C9LAS and 2C10LAS congeners were transformed significantly faster at 30°C, although the optimum temperature for the growth of mixed culture MM1 was 20°C. Simultaneous methane oxidation and LAS transformation, and their mutual competitive inhibition, indicated the involvement of the MMO enzyme system and possible methanotrophic activity in the initiation of cometabolic LAS transformation. The capability of two heterotrophic species to transform sulphophenyldecanoic acid suggests possible heterotrophic activity in further LAS transformation (β-oxidation). Faster LAS transformation by mixed culture MM1 than by pure culture CSC1 suggested that methanotrophic-heterotrophic interactions are important for transformation of the complex LAS molecule.  相似文献   
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