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21.
The objective of this study was to investigate whether it is possible to predict migration fat bloom based on measurements shortly after production. At different storage times shortly after production (0, 1, 4 h), the chocolate batches, varying in tempering method, tempering degree and amount of added butter oil, were evaluated by DSC, pNMR and texture analysis. Discriminant analysis and principal component analysis were combined to investigate the potential towards prediction. The batches were classified into groups depending on the time when white spots appeared (<8 wk, 8–13 wk, >13 wk). A good separation (100% correct classifications, 100% using cross‐validation) was obtained using the afore‐mentioned analyses and storage times. It was also shown that it is possible to exclude DSC analyses or analyses at 0 h storage time without compromising the classification performances too drastically. The study further elucidated that the tempering method has no significant effect on visual fat bloom development. Furthermore, undertempered chocolates bloomed quicker than well‐tempered ones, while fat bloom was delayed on overtempered chocolates. Addition of 6% butter oil promoted fat bloom development, while no significant difference was detected between chocolate with no added butter oil and chocolate with 3% butter oil added.  相似文献   
22.
Intersection accidents result in a significant proportion of road fatalities, and attention allocation likely plays a role. Attention allocation may depend on (limited) working memory (WM) capacity. Driving is often combined with tasks increasing WM load, consequently impairing attention orienting. This study (n = 22) investigated WM load effects on event-related potentials (ERPs) related to attention orienting. A simulated driving environment allowed continuous lane-keeping measurement. Participants were asked to orient attention covertly towards the side indicated by an arrow, and to respond only to moving cars appearing on the attended side by pressing a button. WM load was manipulated using a concurrent memory task. ERPs showed typical attentional modulation (cue: contralateral negativity, LDAP; car: N1, P1, SN and P3) under low and high load conditions. With increased WM load, lane-keeping performance improved, while dual task performance degraded (memory task: increased error rate; orienting task: increased false alarms, smaller P3).

Practitioner Summary: Intersection driver-support systems aim to improve traffic safety and flow. However, in-vehicle systems induce WM load, increasing the tendency to yield. Traffic flow reduces if drivers stop at inappropriate times, reducing the effectiveness of systems. Consequently, driver-support systems could include WM load measurement during driving in the development phase.  相似文献   

23.
Within the context of cloud computing, efficient resource management is of great importance as it can result in higher scalability and significant energy and cost reductions over time. Because of the high complexity and costs of cloud environments, however, newly developed resource allocation strategies are often only validated by means of simulations, for example, by using CloudSim or custom-developed simulation tools. This article describes a general approach for the validation of cloud resource allocation strategies, illustrating the importance of experimental validation on physical testbeds. Furthermore, the design and implementation of Raspberry Pi as a Service (RPiaaS), a low-cost embedded testbed built using Raspberry Pi nodes, is presented. RPiaaS aims to facilitate the step from simulations toward experimental evaluations on larger cloud testbeds and is designed using a microservice architecture, where experiments and all required management services are running inside containers. The performance of the RPiaaS testbed is evaluated using several benchmark experiments. The obtained results not only illustrate that the overhead of both using containers and running the required RPiaaS services is minimal but also provide useful insights for scaling up experiments between the Raspberry Pi testbed and a larger more traditional cloud testbed. The introduced validation approach is then illustrated using a case study focusing on the allocation of hierarchically structured tenant data. The results obtained through simulations are compared to the experimental results. The RPiaaS testbed proved to be a very useful tool for the initial experimental validation before moving the experiments to a large-scale testbed.  相似文献   
24.
Despite the growing importance of ergonomics and ergonomists worldwide, the position of ergonomics in companies is often not clear. Today, in many countries ergonomics is mainly (or even only) associated with the reduction of risks of work-related musculoskeletal disorders (WMSDs). Therefore, many companies consider ergonomics a part of occupational safety and health (OSH) that focuses mainly on the reduction of risks. This paper aims to analyse the links between occupational ergonomics and OSH. The position of occupational ergonomics in legislation, the presence of ergonomics in OSH networks, and the position of ergonomics in OSH company services are discussed. In addition, the added value of ergonomics to companies is examined. From these discussions, it becomes clear that ergonomics should be part of the OSH policy of companies, and should be integrated into today's company strategies to improve labour conditions. If ergonomics is considered as a discipline in its own right, a clear legislative context should be developed that goes beyond voluntary guidelines and the goodwill of employers, and necessitates the presence of ergonomics professionals in companies.  相似文献   
25.
Literature shows that running on an accelerated motorized treadmill is mechanically different from accelerated running overground. Overground, the subject has to enlarge the net anterior–posterior force impulse proportional to acceleration in order to overcome linear whole body inertia, whereas on a treadmill, this force impulse remains zero, regardless of belt acceleration. Therefore, it can be expected that changes in kinematics and joint kinetics of the human body also are proportional to acceleration overground, whereas no changes according to belt acceleration are expected on a treadmill. This study documents kinematics and joint kinetics of accelerated running overground and running on an accelerated motorized treadmill belt for 10 young healthy subjects. When accelerating overground, ground reaction forces are characterized by less braking and more propulsion, generating a more forward-oriented ground reaction force vector and a more forwardly inclined body compared with steady-state running. This change in body orientation as such is partly responsible for the changed force direction. Besides this, more pronounced hip and knee flexion at initial contact, a larger hip extension velocity, smaller knee flexion velocity and smaller initial plantarflexion velocity are associated with less braking. A larger knee extension and plantarflexion velocity result in larger propulsion. Altogether, during stance, joint moments are not significantly influenced by acceleration overground. Therefore, we suggest that the overall behaviour of the musculoskeletal system (in terms of kinematics and joint moments) during acceleration at a certain speed remains essentially identical to steady-state running at the same speed, yet acting in a different orientation. However, because acceleration implies extra mechanical work to increase the running speed, muscular effort done (in terms of power output) must be larger. This is confirmed by larger joint power generation at the level of the hip and lower power absorption at the knee as the result of subtle differences in joint velocity. On a treadmill, ground reaction forces are not influenced by acceleration and, compared with overground, virtually no kinesiological adaptations to an accelerating belt are observed. Consequently, adaptations to acceleration during running differ from treadmill to overground and should be studied in the condition of interest.  相似文献   
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27.
Fluid flow through porous natural building stones is of great importance when studying their weathering processes. Many traditional experiments based on mass changes are available for studying liquid transport in porous stones, such as the determination of the water absorption coefficient by capillarity. Because thermal neutrons experience a strong attenuation by hydrogen, neutron radiography is a suitable technique for the study of water absorption by capillarity in porous stones. However, image contrast can be impaired because hydrogen mainly scatters neutrons rather than absorbing them, resulting in a blurred image. Capillarity results obtained by neutron radiography and by the European Standard 1925 for the determination of the water absorption coefficient by capillarity for natural building stones with a variable porosity were compared. It is illustrated that high-speed neutron radiography can be a useful research tool for the visualization of internal fluid flow inside inorganic building materials such as limestones and sandstones.  相似文献   
28.
The durability of building materials with respect to salt crystallization is commonly determined by accelerated weathering tests, carried out in the laboratory. An effective laboratory weathering test should assess the durability and, in the case of conservation of historic buildings, the compatibility of repair materials with those existing. Besides, the test should provide reliable results within a reasonable period of time, accelerating the deterioration process without however altering its mechanism. Despite several national and international standards, recommendations and guidelines, a commonly accepted testing protocol does not yet exist. Researchers often develop and apply their own procedure, a fact that complicates comparison between different studies. The RILEM Technical Committee 271 ASC has been set up with the scope of developing improved test procedures for the assessment of the behaviour of materials under the influence of salt crystallization, which should overcome the limitations of existing standards and recommendations. This paper constitutes one of the first results of the work of the Technical Committee. It critically reviews the literature on salt crystallization tests, identifies advantages and limitations of the several test protocols and provides new ideas for the development of improved salt crystallization procedures.  相似文献   
29.

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Housing indicators in europe, a tool for housing research and housing policy?  相似文献   
30.
The survey data for this article was collected by the Center for Social Policy (Antwerp University). At regular intervals, they question a representative number of Belgian families in order to make the operation and effects of social policy measurable. On the basis of that data, this article traces the evolution of housing indicators in Flanders, the Dutch-speaking part of Belgium. After outlining the key issues in housing policy in Belgium and Flanders, the article presents the facts: for several population groups, it sketches the developments of tenure, housing amenities, housing costs, and affordability. The emerging picture is one of overall improvement. Nevertheless, some groups lag behind, while new social groups in need of housing emerge (e.g., lone parents). Age and the number of incomes per family seem to be the breaking points. The second part deals specifically with the housing situation of young families (head under 40 years of age). This population group is (historically) responsible for most new building of houses in Belgium and Flanders. Since we observe a decline in ownership, the reasons for this decline are of strategic importance to our understanding of the level of new housing construction and scarcity on the housing market. At the time of the research,Pascal De Decker (sociologist and urban planner) held an appointment at the Center for Housing and Housing Policy (Steunpunt voor Wonen en Woonbeleid) at Antwerp University (UFSIA). At present, he is an expert consultant to the Cabinet of the Flemish Minister for Urban Policy and Housing. Bert Meulemans (sociologist) supervised the reported research on target groups. He is a researcher at the Center for Social Policy (Centrum voor Sociaal Beleid) at Antwerp University (UFSIA) Veerle Geurts (criminologist) is a researcher at the Center for Housing and Housing Policy (Steunpunt voor Wonen en Woonbeleid) at Antwerp University (UFSIA)  相似文献   
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