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101.
Usability and user experience (UX) methods come from academic environments, where industrial conditions such as time and resources are not of prime importance. Furthermore, usability and UX methods originate from a time when almost all software developments followed a traditional approach, such as the waterfall model. These two facts entail that existing methods often are too resource demanding and complex to apply directly into today’s agile, industrial environments. In this paper we make the claim that methods must be updated and tailored in order to be applicable within the agile, industrial development framework of today. We pursue a solution to simplify well-known methods and to train software developers to perform the UX work. To do this, three methods are modified via an iterative process together with the development of supporting materials. Software developers in three companies are trained in the methods to assess the approach. We find that it indeed is feasible to update and tailor existing usability and UX methods to fit into an agile, industrial environment. Furthermore, we show that it is possible to train developers to perform the usability and UX methods via one-day, in-situ sessions using an ‘instructor’-teaching approach. The training is based on hands-on exercises and real-life tasks. This further boosts the developers’ confidence in performing UX work and promises a better consideration of UX in the development phases. We evaluate our approach through observations of the developers performing the UX tasks on their own at a later point in time.  相似文献   
102.
The decolorization and mineralization of two reactive dyes C.I. Reactive Blue 4 (RB 4) and C.I. Reactive Blue 268 (RB 268) were studied using various advanced oxidation processes (AOPs) such as H2O2/UV, H2O2/UV/Fe2+, and the H2O2/UV/Fe°. All processes were performed within a laboratory-scale photo-reactor setup. The experimental results were assessed in terms of absorbance (A) and total organic carbon (TOC) reduction. The main degradation products were identified by high resolution gas chromatography/high resolution mass spectrometry analyses. The results of our study demonstrated that the additions of moderate concentrations of H2O2 and Fe catalyst during the AOPs evidently increased the decolorization efficiencies within the first few minutes of the processing time (5–10 min) for both tested dyes, and prolonged irradiation does not necessarily significantly improve decolorization. On contrary, TOC removal rate increased with the processing time and with the addition of the catalyst from 40–50% up to 70–80% at defined experimental conditions. All the tested AOPs were very successful methods for RB 268 decolorization, having very complex structure and much higher molecular weight compared to the dye RB 4. This is important from both economic and ecological points of view.  相似文献   
103.
Understanding transport diffusion on a molecular level helps to develop improved adsorbents with tailored rate and equilibrium properties. Dual-control-volume grand canonical molecular dynamics (DCV-GCMD) simulations allow the direct simulation of transport diffusion on a molecular level. DCV-GCMD simulations of CH4/CF4 mixtures in carbon nanotubes were carried out. An approach to get composition dependent transport diffusivities directly from DCV-GCMD simulations is introduced. Composition dependent transport diffusivities and fluxes are calculated for varying driving forces in order to investigate the influence of the very large driving force in simulations which is about four orders of magnitude larger than in real experimental systems. Whereas, the flux depends on the driving force the transport diffusivity is independent of it so that DCV-GCMD simulation can be used to simulate transport under experimental conditions. Furthermore, the results of composition dependent diffusivities at four different temperatures are presented. A linear function describes the composition dependence and reproduces the simulated concentration profiles very well. The analysis of the temperature dependence indicates that the transport in the investigated system is due to liquid-like molecular diffusion and not to activated diffusion.  相似文献   
104.
This study examined the following: effects of simulated firefighting (FF) activities under heat stress on sustained attention; whether incident rehabilitation (IR) influences performance; and relationships between performance, affect and personality. Firefighters performed ~18 min of FF. Attention, physiological, perceptual and psychological assessments were made before and after FF, IR and recovery. IR had no effects. Self-rated Energy increased, Tiredness decreased and Anxiety increased immediately post-FF; all returned to baseline 120 min post. The immediate effect of FF was faster reaction time (RT) followed by slowing after recovery. Perceived Energy at baseline was associated (p-values < 0.05) with faster and Tiredness with slower post-FF RTs; Accuracy was unaffected. Conscientiousness was negatively associated with RT before and 120 min following FF. RTs were faster following FF, accuracy was unchanged. Higher baseline Energy/lower Tiredness were associated with faster, less variable RTs at baseline and post-FF. Those with higher Conscientiousness had faster RTs. Research should further investigate higher-level cognitive processing following, or ideally during, FF.  相似文献   
105.
This paper reports on research related to the removal of heavy metal ions, such as lead, nickel, and zinc from wastewater by using tree leaves. Twelve different kinds of tree leaves were tested at room temperature. The experiments were carried out with 2 g of 40-50 mesh leaves in 200 mL synthetic wastewater containing about 50 mg/L metal ions. The initial pH of the synthetic wastewater was about 5. The experiments showed that the highest removal rates were 96% for lead (Pb ++ ), 61.7% for nickel (Ni ++ ), and 71.3% for zinc (Zn ++ ), compared with 93.9% for lead, 68.5% for nickel, and 72.1% for zinc achieved by activated carbon. Tree leaves appear to beagoodadsorbent for metal ion removal from wastewater.  相似文献   
106.
The authors present a retrospective epidemiological study on retinopathy of prematurity (ROP), performed on 738 newborns with a gestational age of 34 +/- 2.41 weeks and birth weight of 1971 +/- 351 g. They excluded all cases with severe respiratory distress and other pathological conditions. First stage of ROP shows no correlation with gestational age and birth weight, whereas second and third stages of ROP show an inverse correlation with the above mentioned factors, particularly birth weight. Among neonates with the same gestational age, the incidence of ROP is higher in those "small for date". Regarding the pathogenesis of ROP, the authors outline the importance of perinatal hypoxia.  相似文献   
107.
ABSTRACT

The performance of a virtual reality (VR) system can be assessed from two aspects in the human-VR interaction loop. One aspect is the degree of immersion, which objectively quantifies the performance of the VR system using metrics such as the display field of view or the refresh rate. The other aspect is presence, which measures the user response to the VR system. This article presents a study that compares the impact on presence by changing immersion through enabling and disabling of the head tracking ability on a VR headset. The study quantitatively assesses this change by taking objective measurements of posture and subjective ratings of the VR experience, in terms of presence and motion sickness, after participants have gone through two versions of a roller coaster simulation; one with head tracking on and the other with head tracking off. The results indicate that a loss of immersion, caused by turning the head tracking feature off, results in a significant reduction in postural sway. This loss of immersion also affected presence, as shown through the user surveys. The survey responses indicate that the simulation with head tracking off was less enjoyable and caused more motion sickness compared to when head tracking is kept on.  相似文献   
108.
The purpose of this research study is to identify whether academic librarians teach upper-division students about print reference resources, and how they teach students to use them. Questionnaires were sent to library instruction and reference services e-mail discussion lists. After analyzing results, researchers found that responses focused on the themes of pro-print, pro-electronic, relevance to instruction, collection development, and marketing. Using print reference in library instruction is related to the type of research assignment and electronic format availability. Librarians may want to consider engaging students in hands-on use of print and electronic reference material, so students are able to navigate the breadth of information sources.  相似文献   
109.
Initiatives that seek to realize the vision of nation-wide information infrastructures (II) in healthcare have often failed to achieve their goals. In this paper, we focus on approaches used to plan, conduct, and manage the realization of such visions. Our empirical material describes two Danish initiatives, where a national project failed to deliver interoperable Electronic Patient Record (EPR) systems while a small, local solution grew and now offers a nation-wide solution for sharing patient record information. We apply II theory, specifically the five design principles proposed by Hanseth and Lyytinen, to contrast the organization and implementation strategies of the two projects. Our findings highlight how implementation strategies differ with respect to how stakeholders are mobilized. We argue that the realization of nation-wide IIs for healthcare not only requires a gradual transition of the installed base, which current II theory advocates. Here we articulate and exemplify a modular implementation strategy as an approach that also addresses the challenges related to mobilization and organization of multiple stakeholders.  相似文献   
110.
This paper evaluates the impact of alternative city boundary definitions on economic performance. First we discuss the theoretical background and motivate the empirical work. Then we present the methodological concept of the sensitivity analysis, which will be applied to a variety of data of Zürich and Bern (the financial and the administrative centres of Switzerland) in order to see how the values of different indicators vary depending on the definition adopted. Finally we will show whether the empirical patterns found are statistically significant. The analysis shows, that the delimitation of a city or city region indeed matters.  相似文献   
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