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排序方式: 共有419条查询结果,搜索用时 15 毫秒
31.
This paper presents practical experience in planning, implementing, and adopting a Quality Management System (QMS) for embedded systems development at VTT Electronics. The main objective for the development of the QMS was to make it practical for real-life embedded systems research and development (R&D) projects. We have applied the ISO 9001 standard and ISO 9000–3 guidelines in building the quality system. From our personnel's point of view, the most important parts of the system have been document skeletons and plan templates that were made accessible to everyone. One of the major quality improvement resulting from the use of the QMS has been the enhanced predictability of R&D projects. This makes it possible for the organization to concentrate on essential matters. From our clients' point of view, we have clearly improved the quality of our R&D services in terms of the customer satisfaction index. Based on QMS auditing activities, we have been able to evaluate and tune our R&D procedures in a systematic manner. We have decided to use Total Quality Management and Quality Award frameworks in the further development of the QMS. Customer service and human resources management are examples of important areas for further quality improvement. 相似文献
32.
Atomic layer deposition of transition metals 总被引:1,自引:0,他引:1
Atomic layer deposition (ALD) is a process for depositing highly uniform and conformal thin films by alternating exposures of a surface to vapours of two chemical reactants. ALD processes have been successfully demonstrated for many metal compounds, but for only very few pure metals. Here we demonstrate processes for the ALD of transition metals including copper, cobalt, iron and nickel. Homoleptic N,N'-dialkylacetamidinato metal compounds and molecular hydrogen gas were used as the reactants. Their surface reactions were found to be complementary and self-limiting, thus providing highly uniform thicknesses and conformal coating of long, narrow holes. We propose that these ALD layers grow by a hydrogenation mechanism that should also operate during the ALD of many other metals. The use of water vapour in place of hydrogen gas gives highly uniform, conformal films of metal oxides, including lanthanum oxide. These processes should permit the improved production of many devices for which the ALD process has previously not been applicable. 相似文献
33.
We introduce a new approach for finding overlapping clusters given pairwise similarities of objects. In particular, we relax the problem of correlation clustering by allowing an object to be assigned to more than one cluster. At the core of our approach is an optimization problem in which each data point is mapped to a small set of labels, representing membership in different clusters. The objective is to find a mapping so that the given similarities between objects agree as much as possible with similarities taken over their label sets. The number of labels can vary across objects. To define a similarity between label sets, we consider two measures: (i) a 0–1 function indicating whether the two label sets have non-zero intersection and (ii) the Jaccard coefficient between the two label sets. The algorithm we propose is an iterative local-search method. The definitions of label set similarity give rise to two non-trivial optimization problems, which, for the measures of set-intersection and Jaccard, we solve using a greedy strategy and non-negative least squares, respectively. We also develop a distributed version of our algorithm based on the BSP model and implement it using a Pregel framework. Our algorithm uses as input pairwise similarities of objects and can thus be applied when clustering structured objects for which feature vectors are not available. As a proof of concept, we apply our algorithms on three different and complex application domains: trajectories, amino-acid sequences, and textual documents. 相似文献
34.
A double approach method for versatile detection of similar objects from the real environment is introduced. By searching both the shape and textural data from the video image, it is possible to solve a generalized location problem without a loss in overall reliability in near–real time. A forest forwarder is used as a proof-of-concept application for the technique. 相似文献
35.
In an experiment conducted to study the effects of product expectations on subjective usability ratings, participants (N = 36) read a positive or a negative product review for a novel mobile device before a usability test, while the control group read nothing. In the test, half of the users performed easy tasks, and the other half hard ones, with the device. A standard usability test procedure was utilized in which objective task performance measurements as well as subjective post-task and post-experiment usability questionnaires were deployed. The study revealed a surprisingly strong effect of positive expectations on subjective post-experiment ratings: the participants who had read the positive review gave the device significantly better post-experiment ratings than did the negative-prime and no-prime groups. This boosting effect of the positive prime held even in the hard task condition where the users failed in most of the tasks. This finding highlights the importance of understanding: (1) what kinds of product expectations participants bring with them to the test, (2) how well these expectations represent those of the intended user population, and (3) how the test situation itself influences and may bias these expectations. 相似文献
36.
Ohne Zusammenfassung 相似文献
37.
Antti Roose Kadri Reinsoo Ahto Oja Visvaldas Var?inskas 《Clean Technologies and Environmental Policy》2012,14(6):1085-1093
The production and use of biogas, along with corresponding sector-specific activities and technologies, is a relatively new subject in Estonia. This paper gives an instructive overview of main barriers behind the development incentives, policy support and technological innovation in terms of emerging market for biogas. The article examines the complexity of market-related, political, technological and social obstacles for introduction biogas technologies. There is a major gap between resource potential, technological capacity and practice in Estonia. About 2?% of the theoretical potential of biogas is being used, totalling around 11?million?Nm3, based primarily on landfill biogas. First, political setting for biogas innovation is still vague, however, consolidated and enhanced since 2010 to compete with other renewables and mainstream energy technologies. The article underlines the statement that the reason why Estonian biogas production has not followed the path of growth and technology transfer is the low renewable electricity feed-in tariff. However, there are many other legal and engineering factors that have held back biogas applications and sector development in general. Stakeholders have established the Estonian Biogas Association, increasing sector’s visibility, targeted lobby to support policy-making, technological and social innovation and professional networking. Though getting the biogas sector to succeed demands a comprehensive approach and involvement of more actors in demand side including local leaders and consumers, both enthusiasm and scepticism should be informed by a sound understanding of framework conditions and complexities for path-breaking transformations in energy systems. To promote biogas production, profitable and technologically feasible showcases should demonstrate benefits and issues to the target group and stakeholders. Instead agricultural and CHP development mode, the priority of using biogas in Estonia could be seen as green vehicle fuel for transport. 相似文献
38.
Mingzhou Yu Antti Joonas Koivisto Kaarle Hämeri Martin Seipenbusch 《Aerosol science and technology》2013,47(4):427-434
A thorough understanding of the importance of aerosol coagulation and deposition relative to each other as modifiers of the particle size distribution plays an important role in the proper selection of conditions to estimate the deposition rate coefficient. In this work, a theoretical analysis was conducted for investigating the size-resolved ratio of coagulation to deposition for different types of size distributions using the Simpson integral method. The theoretical model was subsequently qualitatively validated by experiments in a completely mixed and ventilated aerosol chamber. Both experimental and theoretical studies show that the ratio of the rates of coagulation to deposition is strongly dependent on the total particle number concentration and the geometric mean diameter of the aerosol. A variation of the ratio of coagulation to deposition by several orders of magnitude for aerosols with differing size distributions was found. Thus the previously employed criterion for the negligence of coagulation based solely on the total particle number concentration was shown to be insufficient to accurately judge whether an aerosol is suited for the estimation of the deposition rate coefficient. Aerosols with wide size distributions are not recommended for use in the estimation of the deposition rate coefficient. The study provides a method to understand the role of coagulation and deposition for indoor aerosols. Copyright 2013 American Association for Aerosol Research 相似文献
39.
Tiina Sikanen Thomas Zwinger Santeri Tuomikoski Sami Franssila Reijo Lehtiniemi Carl-Magnus Fager Tapio Kotiaho Antti Pursula 《Microfluidics and nanofluidics》2008,5(4):479-491
This work presents experimental [infrared (IR) thermography] and computational (finite element model) results of temperature
distributions of an electrokinetic separation chip. Thermal characteristics of both the electrolyte solution and the polymer
chip (SU-8) are taken into account in modeling temperature distributions during electrokinetic flow. Multiphysics and multiscale
simulation couples electrostatics, heat transfer, and fluid dynamics. The accompanying IR thermography is a non-contact method,
which can measure fractional temperature differences with sub-second time resolution. Any structures or temperature marker
molecules interfering with the experiment are not needed. Nominal spot size in the IR measurements is 30 μm with a field of
view of several millimeters enabling both local and chip-scale temperature monitoring simultaneously. As a result, we present
a computer model for electrokinetic chips, which enables simulation of fractional temperature changes during electrophoresis
under real operating conditions. The accuracy of the model is within ±1°C when the deviation in electrochemical processes
is taken into account. The simulation results also suggest that the temperature on the chip surface qualitatively reflects
the temperature inside the microchannel with an average offset of 1–2°C. 相似文献
40.