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131.
John van den Hoven 《Information Systems Management》2004,21(3):61-64
The modern enterprise has become increasingly dependent on data and its value-added forms of information and knowledge to remain competitive in the face of global competition and constant change. Data architecture provides the framework necessary to use and share data more effectively, and to improve the flow of data between systems within the enterprise and between the enterprise's systems and those of its customers, suppliers, and business partners. Data architecture standards constitute the foundation of an effective data architecture. 相似文献
132.
Suzan Verberne Emiel Krahmer Iris Hendrickx Sander Wubben Antal van den Bosch 《Language Resources and Evaluation》2018,52(2):461-483
In this paper we address extractive summarization of long threads in online discussion fora. We present an elaborate user evaluation study to determine human preferences in forum summarization and to create a reference data set. We showed long threads to ten different raters and asked them to create a summary by selecting the posts that they considered to be the most important for the thread. We study the agreement between human raters on the summarization task, and we show how multiple reference summaries can be combined to develop a successful model for automatic summarization. We found that although the inter-rater agreement for the summarization task was slight to fair, the automatic summarizer obtained reasonable results in terms of precision, recall, and ROUGE. Moreover, when human raters were asked to choose between the summary created by another human and the summary created by our model in a blind side-by-side comparison, they judged the model’s summary equal to or better than the human summary in over half of the cases. This shows that even for a summarization task with low inter-rater agreement, a model can be trained that generates sensible summaries. In addition, we investigated the potential for personalized summarization. However, the results for the three raters involved in this experiment were inconclusive. We release the reference summaries as a publicly available dataset. 相似文献
133.
D. C. Hermes T. Heuser E. J. van der Wouden J. G. E. Gardeniers A. van den Berg 《Microsystem Technologies》2006,12(5):436-440
In this paper a method is presented for the fabrication of micro-channel networks in glass with integrated and insulated gate electrodes to control the zeta-potential at the insulator surface and therewith the electro-osmotic flow (EOF). The fabrication of the electrodes is a sequence of photolithography, etching and thin film deposition steps on a glass substrate, followed by chemical mechanical polishing (CMP) and subsequently direct thermal bonding to a second glass plate to form closed micro-channels. Plasma enhanced chemical vapor deposition (PECVD) SiO2-layers as insulating material between the electrodes and micro-channels and different electrode materials are examined with respect to a high bonding temperature to obtain an optimal insulating result. A CMP process for the reduction of the SiO2 topography and roughness is studied and optimized in order to obtain a surface that is smooth enough to be directly bondable to a second glass plate. 相似文献
134.
随着空前规模与速度的城市化进程,在上个十年中,上海周边的乡村地区发生了惊人的变化。在离散化的政策下,许多新城与郊区依次落成。每一个地区独特的物质条件与规章制度形成新区难以预计的多样性,同时也造成空间与功能性品质的多样化。大多数新区都依据标准步骤进行开发。一些试点新城的开发通过文本形式在西方设计师的帮助下适应中国的规范;另一些新城与街区由来自中国的新锐建筑师与规划师设计。本文主要介绍嘉定与青浦区的发展成果。 相似文献
135.
E vanSonnenberg GR Wittich KS Chon HB D'Agostino G Casola D Easter RG Morgan EM Walser WH Nealon B Goodacre BE Stabile 《Canadian Metallurgical Quarterly》1997,168(4):979-984
OBJECTIVE: The purpose of our study was to review and report the patient selection, techniques, and results of percutaneous drainage of pancreatic abscesses by retrospective review. MATERIALS AND METHODS: Fifty-nine patients (46 men and 13 women) with a mean age of 44 years old had 80 pancreatic abscesses that were drained percutaneously under radiologic guidance (CT, n = 77; sonography, n = 2; and fluoroscopy, n = 1). Abscesses had a wide spectrum of causes, with alcoholic pancreatitis being most common, trauma second most common, and gallstones third. Ten patients had undergone surgery for pancreatic necrosis or abscess. Patients with pancreatic pseudocysts, necrosis, or acute fluid collections were excluded from this study. RESULTS: Of the 59 patients, 51 (86%) were cured with percutaneous drainage and antibiotic therapy. Of the patients who were not cured with percutaneous drainage, seven required surgery and one underwent repeat percutaneous drainage. In the 59 patients, complications included non-life-threatening bleeding in three patients. Ten of 59 patients (17%) had fistulas that spontaneously formed into the gastrointestinal tract. The duration of catheterization ranged from 4 to 119 days, with a mean duration of 33 days. The rate of mortality at 30 days after completion of percutaneous drainage was 8% (5 of 59). CONCLUSION: Percutaneous drainage was an effective therapy for this defined group of patients with pancreatic abscesses. Factors leading to the relatively high success rate described in this study likely included selection of patients; catheters of adequate size, number, and location; careful follow-up with appropriate catheter manipulations; and an integrated, cooperative approach whereby surgeons were willing to permit drainage to effect its benefits, rather than operating prematurely. 相似文献
136.
M. Javad Mohajeri Arjan J. van den Bergh Jovana Jovanova Dingena L. Schott 《Advanced Powder Technology》2021,32(5):1723-1734
Ship unloader grabs are usually designed using the manufacturer’s in-house knowledge based on a traditional physical prototyping approach. The grab performance depends greatly on the properties of the bulk material being handled. By considering the bulk cargo variability in the design process, the grab performance can be improved significantly. A multi-objective simulation-based optimization framework is therefore established to include bulk cargo variability in the design process of grabs. The primary objective is to reach a maximized and consistent performance in handling a variety of iron ore cargoes. First, a range of bulk materials is created by varying levels of cohesive forces and plasticity in the elasto-plastic adhesive DEM contact model. The sensitivity analysis of the grabbing process to the bulk variability allowed three classes of iron ore materials to be selected that have significant influence on the product performance. Second, 25 different grab designs are generated using a random sampling method, Latin Hypercube Design, to be assessed as to their handling of the three classes of iron ore materials. Of this range of grab designs, optimal solutions are found using surrogate modelling-based optimization and the NSGA-II genetic algorithm. The optimization outcome is verified by comparing predictions of the optimization algorithm and results of DEM-MBD co-simulation. The established optimization framework offers a straightforward and reliable tool for designing grabs and other similar equipment. 相似文献
137.
Sylvain Degrandsart Serge Demeyer Jan Van den Bergh Tom Mens 《Software and Systems Modeling》2014,13(1):191-208
Context-aware computing is a paradigm for governing the numerous mobile devices surrounding us. In this computing paradigm, software applications continuously and dynamically adapt to different “contexts” implying different software configurations of such devices. Unfortunately, modelling a context-aware application (CAA) for all possible contexts is only feasible in the simplest of cases. Hence, tool support verifying certain properties is required. In this article, we introduce the CAA model, in which context adaptations are specified explicitly as model transformations. By mapping this model to graphs and graph transformations, we can exploit graph transformation techniques such as critical pair analysis to find contexts for which the resulting application model is ambiguous. We validate our approach by means of an example of a mobile city guide, demonstrating that we can identify subtle context interactions that might go unnoticed otherwise. 相似文献
138.
Sung Wook Hwang Jin Kie Shim Susan EM Selke Herlinda Soto‐Valdez Laurent Matuana Maria Rubino Rafael Auras 《Polymer International》2012,61(3):418-425
Poly(L ‐lactic acid) (PLLA) films containing various concentrations of two natural antioxidants, α‐tocopherol and resveratrol, were fabricated by a melt compounding and compression molding process. The influence of the antioxidants on the optical properties such as color and UV‐visible light transmission was analyzed. The thermal, mechanical, rheological and physical properties of PLLA films with added antioxidants were assessed. PLLA films with added α‐tocopherol and resveratrol showed a yellowish brown color and the lightness was influenced by the presence of the antioxidants. The glass transition and melting temperatures were significantly reduced with the addition of antioxidants while enhanced thermal stability was observed, which could be a benefit and important for processing and production. PLLA films with added antioxidants were slightly more hydrophobic than neat PLLA. The combination effect of plasticizing and enhancement of the elastic modulus with differing concentrations of two antioxidants played a critical role in the mechanical and thermomechanical properties of PLLA films. The melt viscosity of the PLLA films with added antioxidants was substantially higher than that of neat PLLA. The higher melt viscosity and G′(ω) could be an indication of formation of entanglement between PLLA and the two antioxidants. Copyright © 2012 Society of Chemical Industry 相似文献
139.
This study concerns an innovative project in the Dutch river Waal: the construction of longitudinal dams. By splitting the river into a main and secondary channel, these dams significantly impact the river landscape and the way it is used by different stakeholders. We report the results of a baseline study of the expectations local water-based recreationists (fishermen and boaters) had of the longitudinal dams before they were constructed. In addition, we explore their levels of place attachment, and use the visions of nature approach to elicit their lay philosophy of nature. We found that fishermen were more strongly attached to the area than boaters. Though expectations of the dams were generally negative, this differed significantly between fishermen and boaters, and between different dimensions of landscape change. We demonstrate the relevance of place attachment and visions of nature for understanding how recreationists perceive landscape change. 相似文献
140.
We investigate an automated identification of weak signals according to Ansoff to improve strategic planning and technological forecasting. Literature shows that weak signals can be found in the organization’s environment and that they appear in different contexts. We use internet information to represent organization’s environment and we select these websites that are related to a given hypothesis. In contrast to related research, a methodology is provided that uses latent semantic indexing (LSI) for the identification of weak signals. This improves existing knowledge based approaches because LSI considers the aspects of meaning and thus, it is able to identify similar textual patterns in different contexts. A new weak signal maximization approach is introduced that replaces the commonly used prediction modeling approach in LSI. It enables to calculate the largest number of relevant weak signals represented by singular value decomposition (SVD) dimensions. A case study identifies and analyses weak signals to predict trends in the field of on-site medical oxygen production. This supports the planning of research and development (R&D) for a medical oxygen supplier. As a result, it is shown that the proposed methodology enables organizations to identify weak signals from the internet for a given hypothesis. This helps strategic planners to react ahead of time. 相似文献